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thesis.bib
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%% This BibTeX bibliography file was created using BibDesk.
%% http://bibdesk.sourceforge.net/
%% Created for Bruno SAN at 2008-08-29 12:25:23 +0200
%% Saved with string encoding Western (ASCII)
@phdthesis{Sanchez-Andrade-Nuno:2008fe,
Author = {{S{\'a}nchez-Andrade Nu{\~n}o}, B.},
Date-Added = {2008-08-29 12:22:23 +0200},
Date-Modified = {2008-08-29 12:24:12 +0200},
Read = {Yes},
School = {University of Goettingen},
Title = {Observations, analysis and interpretation with non-LTE of chromospheric structures on the Sun"},
Year = {2008},
Bdsk-Url-1 = {http://www.astro.physik.uni-goettingen.de/~bruno/thesis/Thesis-brunosan.zip}}
@article{1994A&A...290..285T,
Adsnote = {Provided by the SAO/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/1994A%26A...290..285T},
Author = {{Tsiropoula}, G. and {Alissandrakis}, C.~E. and {Schmieder}, B. },
Date-Added = {2008-08-29 11:41:32 +0200},
Date-Modified = {2008-08-29 11:41:32 +0200},
Journal = {\aap},
Keywords = {LINES: PROFILE, SUN: CHROMOSPHERE},
Month = oct,
Pages = {285-294},
Title = {{Time evolution of fine structures in the solar chromosphere.}},
Volume = 290,
Year = 1994}
@article{cente07,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/2007arXiv0712.2203C},
Author = {{Centeno}, R. and {Trujillo Bueno}, J. and {Uitenbroek}, H. and {Collados}, M.},
Date-Added = {2007-12-14 16:30:03 +0100},
Date-Modified = {2007-12-14 16:30:11 +0100},
Eprint = {0712.2203},
Journal = {ArXiv e-prints},
Month = dec,
Title = {{The influence of coronal EUV irradiance on the emission in the He I 10830 A and D3 multiplets}},
Volume = 712,
Year = 2007}
@article{spruit81,
Abstract = {General equations of motion are derived for a thin untwisted magnetic flux tube embedded in a non-magnetic compressible fluid, in the presence of gravity. Special equations governing small perturbations in purely horizontal or vertical flux tubes are derived from these. There is in general a longitudinal and a transversal wave mode. The transversal wave in a vertical tube is studied in detail. This wave propagates under the combined influences of buoyancy and magnetic tension along the tube. In an exponential atmosphere it has a cutoff frequency which is at least twice as low as the acoustic cutoff frequency. It can transport a significant amount of energy from the convection zone to the chromosphere. The transversal motions seen in the magnetic field of the chromosphere are interpreted as transversal tube waves generated in the convection zone.},
Annote = {<record><dc:identifier>1981A&A....98..155S</dc:identifier><dc:title>Motion of magnetic flux tubes in the solar convection zone and chromosphere</dc:title><dc:creator>Spruit, H. C.</dc:creator><dc:source>Astronomy and Astrophysics, vol. 98, no. 1, May 1981, p. 155-160.</dc:source><dc:date>1981-05-01</dc:date><dc:subject>CHROMOSPHERE, COMPRESSIBLE FLUIDS, EQUATIONS OF MOTION, GRAVITATIONAL EFFECTS, MAGNETIC FLUX, TRANSVERSE WAVES, CONVECTION, ENERGY TRANSFER, MAGNETIC FIELDS, TRANSVERSE OSCILLATION, WAVE PROPAGATION</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1981A%26A....98..155S</dc:relation><dc:description>General equations of motion are derived for a thin untwisted magnetic
flux tube embedded in a non-magnetic compressible fluid, in the presence
of gravity. Special equations governing small perturbations in purely
horizontal or vertical flux tubes are derived from these. There is in
general a longitudinal and a transversal wave mode. The transversal wave
in a vertical tube is studied in detail. This wave propagates under the
combined influences of buoyancy and magnetic tension along the tube. In
an exponential atmosphere it has a cutoff frequency which is at least
twice as low as the acoustic cutoff frequency. It can transport a
significant amount of energy from the convection zone to the
chromosphere. The transversal motions seen in the magnetic field of the
chromosphere are interpreted as transversal tube waves generated in the
convection zone.</dc:description></record>},
Author = {Spruit, H. C.},
Date = {1981-05-01},
Date-Added = {2007-12-10 10:55:00 +0100},
Date-Modified = {2007-12-16 11:56:52 +0100},
Journal = {\aap},
Keywords = {CHROMOSPHERE, COMPRESSIBLE FLUIDS, EQUATIONS OF MOTION, GRAVITATIONAL EFFECTS, MAGNETIC FLUX, TRANSVERSE WAVES, CONVECTION, ENERGY TRANSFER, MAGNETIC FIELDS, TRANSVERSE OSCILLATION, WAVE PROPAGATION},
Month = {May},
Pages = {155--160},
Title = {Motion of magnetic flux tubes in the solar convection zone and chromosphere},
Url = {http://adsseeks.cfa.harvard.edu/abs/1981A%26A....98..155S},
Volume = {98},
Year = {1981},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1981A&A....98..155S}}
@article{sanchez07,
Author = {B. {S\'anchez-Andrade Nu{\~n}o} and N. {Bello Gonz\'alez} and {Blanco Rodr{\'{\i}}guez}, J. and {Kneer}, F. and {Puschmann}, K.~G.},
Date-Added = {2007-12-06 13:48:29 +0100},
Date-Modified = {2007-12-07 14:53:03 +0100},
Journal = {\aap , submitted},
Title = {{Fast events and waves in solar H$\alpha$ structures at high resolution}},
Year = 2007}
@inproceedings{2007ASPC..368..605B,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/2007ASPC..368..605B},
Author = {{Balthasar}, H. and {von der L{\"u}he}, O. and {Kneer}, F. and {Staude}, J. and {Volkmer}, R. and {Berkefeld}, T. and {Caligari}, P. and {Collados}, M. and {Halbgewachs}, C. and {Heidecke}, F. and {Hofmann}, A. and {Klva{\v n}a}, M. and {Nicklas}, H. and {Popow}, E. and {Puschmann}, K. and {Schmidt}, W. and {Sobotka}, M. and {Soltau}, D. and {Strassmeier}, K. and {Wittmann}, A.},
Booktitle = {The Physics of Chromospheric Plasmas},
Date-Added = {2007-12-05 21:17:21 +0100},
Date-Modified = {2007-12-17 12:28:19 +0100},
Editor = {{Heinzel}, P. and {Dorotovi{\v c}}, I. and {Rutten}, R.~J.},
Local-Url = {file://localhost/data/papers/0704.2693.pdf},
Month = may,
Pages = {605--610},
Series = {Astronomical Society of the Pacific Conference Series},
Title = {{GREGOR: the New German Solar Telescope}},
Volume = 368,
Year = 2007,
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@article{2004A&A...414.1109L,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/2004A%26A...414.1109L},
Author = {{Lagg}, A. and {Woch}, J. and {Krupp}, N. and {Solanki}, S.~K. },
Date-Added = {2007-12-05 21:12:03 +0100},
Date-Modified = {2007-12-05 21:12:03 +0100},
Doi = {10.1051/0004-6361:20031643},
Journal = {\aap},
Month = feb,
Pages = {1109-1120},
Title = {{Retrieval of the full magnetic vector with the He I multiplet at 1083 nm. Maps of an emerging flux region}},
Volume = 414,
Year = 2004,
Bdsk-Url-1 = {http://dx.doi.org/10.1051/0004-6361:20031643}}
@webpage{wikistokes,
Author = {Wikipedia, the free encyclopedia},
Date-Added = {2007-12-01 15:15:19 +0100},
Date-Modified = {2007-12-26 18:45:01 +0100},
Title = {{(http://en.wikipedia.org/wiki/Stokes\_parameters)}},
Url = {http://en.wikipedia.org/wiki/Stokes_parameters},
Year = {{Stokes parameters}},
Bdsk-Url-1 = {http://en.wikipedia.org/wiki/Stokes_parameters}}
@article{hildner74,
Abstract = {Abstract image available at: http://adsseeks.cfa.harvard.edu/abs/1974SoPh...35..123H},
Annote = {<record><dc:identifier>1974SoPh...35..123H</dc:identifier><dc:title>The Formation of Solar Quiescent Prominences by Condensation</dc:title><dc:creator>Hildner, E.</dc:creator><dc:source>\solphys, Volume 35, Issue 1, pp.123-136</dc:source><dc:date>1974-03-01</dc:date><dc:rights>(c) 1974: D. Reidel Publishing Company</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1974SoPh...35..123H</dc:relation><dc:description>Abstract image available at:
http://adsseeks.cfa.harvard.edu/abs/1974SoPh...35..123H</dc:description></record>},
Author = {Hildner, E.},
Date-Added = {2007-12-01 13:58:32 +0100},
Date-Modified = {2007-12-16 11:52:20 +0100},
Journal = {\solphys},
Pages = {123--136},
Title = {The Formation of Solar Quiescent Prominences by Condensation},
Url = {http://adsseeks.cfa.harvard.edu/abs/1974SoPh...35..123H},
Volume = {35},
Year = {1974},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1974SoPh...35..123H}}
@article{wentzel79,
Abstract = {Hydromagnetic surface waves resulting from a magnetic discontinuity are analyzed for the case of cylindrical geometry. The results are applied to cylindrical magnetic flux tubes in the solar photosphere. Physical properties of the hydromagnetic surface waves are discussed, with emphasis on differences between such waves on plane and cylindrical surfaces. It is concluded that possible linear mode conversion between surface and body waves is not affected by cylindrical curvature.},
Annote = {<record><dc:identifier>1979A&A....76...20W</dc:identifier><dc:title>Hydromagnetic surface waves on cylindrical fluxtubes</dc:title><dc:creator>Wentzel, D. G.</dc:creator><dc:source>Astronomy and Astrophysics, vol. 76, no. 1, June 1979, p. 20-23. NSF-supported research.</dc:source><dc:date>1979-06-01</dc:date><dc:subject>MAGNETOHYDRODYNAMIC WAVES, PHOTOSPHERE, ROTATING CYLINDERS, SOLAR MAGNETIC FIELD, SOLAR PHYSICS, SURFACE WAVES, BESSEL FUNCTIONS, DISCONTINUITY, ELECTROSTATIC WAVES, MAGNETIC FLUX, PLANE WAVES, PLASMA CYLINDERS, STELLAR MODELS, WAVE EQUATIONS</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1979A%26A....76...20W</dc:relation><dc:description>Hydromagnetic surface waves resulting from a magnetic discontinuity are
analyzed for the case of cylindrical geometry. The results are applied
to cylindrical magnetic flux tubes in the solar photosphere. Physical
properties of the hydromagnetic surface waves are discussed, with
emphasis on differences between such waves on plane and cylindrical
surfaces. It is concluded that possible linear mode conversion between
surface and body waves is not affected by cylindrical curvature.</dc:description></record>},
Author = {Wentzel, D. G.},
Date = {1979-06-01},
Date-Added = {2007-11-30 20:27:45 +0100},
Date-Modified = {2007-12-16 12:06:55 +0100},
Journal = {\aap},
Keywords = {MAGNETOHYDRODYNAMIC WAVES, PHOTOSPHERE, ROTATING CYLINDERS, SOLAR MAGNETIC FIELD, SOLAR PHYSICS, SURFACE WAVES, BESSEL FUNCTIONS, DISCONTINUITY, ELECTROSTATIC WAVES, MAGNETIC FLUX, PLANE WAVES, PLASMA CYLINDERS, STELLAR MODELS, WAVE EQUATIONS},
Pages = {20--23},
Title = {Hydromagnetic surface waves on cylindrical fluxtubes},
Url = {http://adsseeks.cfa.harvard.edu/abs/1979A%26A....76...20W},
Volume = {76},
Year = {1979},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1979A&A....76...20W}}
@techreport{1992lest.rept....1Y,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1992lest.rept....1Y},
Author = {{Yi}, Z. and {Darvann}, T. and {Molowny-Horas}, R.},
Date-Added = {2007-11-29 16:42:17 +0100},
Date-Modified = {2007-12-16 12:11:09 +0100},
Institution = {Lest foundation, Institute of Theoretical Astrophysics, University of Oslo},
Number = {56},
Pages = {1-+},
Title = {{Software for Solar Image Processing - Proceedings from lest Mini Workshop}},
Year = 1992}
@article{wittmann69,
Abstract = {Not Available},
Annote = {<record><dc:identifier>1969SoPh....7..366W</dc:identifier><dc:title>Some Properties of Umbral Flashes</dc:title><dc:creator>Wittmann, A.</dc:creator><dc:source>\solphys, Volume 7, Issue 3, pp.366-369</dc:source><dc:date>1969-06-01</dc:date><dc:rights>(c) 1969: D. Reidel Publishing Company</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..366W</dc:relation><dc:description>Not Available</dc:description></record>},
Author = {Wittmann, A.},
Date = {1969-06-01},
Date-Added = {2007-11-29 16:37:41 +0100},
Date-Modified = {2007-12-16 12:07:46 +0100},
Journal = {\solphys},
Number = {3},
Pages = {366-369},
Title = {Some Properties of Umbral Flashes},
Url = {http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..366W},
Volume = {7},
Year = {1969},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..366W}}
@article{uexkuell83,
Abstract = {An analysis is made of time sequences of photographic spectrograms in Ca II H, K, 8498 A, and 8542 A, in sodium D1 and D2, and in Ni I 5893 A and H-alpha obtained from two sunspots with the Vacuum Tower Telescope at Sacramento Peak Observatory. The two sunspot chromospheres are found to behave similarly with regard to their phase relationships but somewhat differently with regard to the oscillation resonant frequencies. In one and the same umbra, oscillation modes having different frequencies may be excited. The vertical velocity of propagation of the phase in umbral chromospheres, which is 10-25 km/s, decreases with increasing frequency and is much lower than the Alfven speed. The umbral chromospheric oscillations are thus slow mode waves. The downward motion enhances the intensity by some 65 deg (H-alpha) to 85 deg (D1), indicating dissipation of mechanical energy. It is also found that the mechanical energy flux of the umbral chromospheric oscillations is not sufficient to account for the chromospheric radiative losses.},
Annote = {<record><dc:identifier>1983A&A...123..263U</dc:identifier><dc:title>The chromosphere above sunspot umbrae. IV - Frequency analysis of umbral oscillations</dc:title><dc:creator>Uexkuell, M. V.</dc:creator><dc:creator>Kneer, F.</dc:creator><dc:creator>Mattig, W.</dc:creator><dc:source>Astronomy and Astrophysics (ISSN 0004-6361), vol. 123, no. 2, July 1983, p. 263-270. Sponsorship: Deutsche Forschungsgemeinschaft.</dc:source><dc:date>1983-07-01</dc:date><dc:subject>CHROMOSPHERE, SOLAR OSCILLATIONS, SUNSPOTS, UMBRAS, SOLAR SPECTRA</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1983A%26A...123..263U</dc:relation><dc:description>An analysis is made of time sequences of photographic spectrograms in Ca
II H, K, 8498 A, and 8542 A, in sodium D1 and D2, and in Ni I 5893 A and
H-alpha obtained from two sunspots with the Vacuum Tower Telescope at
Sacramento Peak Observatory. The two sunspot chromospheres are found to
behave similarly with regard to their phase relationships but somewhat
differently with regard to the oscillation resonant frequencies. In one
and the same umbra, oscillation modes having different frequencies may
be excited. The vertical velocity of propagation of the phase in umbral
chromospheres, which is 10-25 km/s, decreases with increasing frequency
and is much lower than the Alfven speed. The umbral chromospheric
oscillations are thus slow mode waves. The downward motion enhances the
intensity by some 65 deg (H-alpha) to 85 deg (D1), indicating
dissipation of mechanical energy. It is also found that the mechanical
energy flux of the umbral chromospheric oscillations is not sufficient
to account for the chromospheric radiative losses.</dc:description></record>},
Author = {von Uexk{\"u}ll, M. and Kneer, F. and Mattig, W.},
Date = {1983-07-01},
Date-Added = {2007-11-29 16:35:18 +0100},
Date-Modified = {2007-12-16 12:08:58 +0100},
Journal = {\aap},
Keywords = {CHROMOSPHERE, SOLAR OSCILLATIONS, SUNSPOTS, UMBRAS, SOLAR SPECTRA},
Number = {2},
Pages = {263--270},
Title = {{The chromosphere above sunspot umbrae. IV~-~Frequency analysis of umbral oscillations}},
Url = {http://adsseeks.cfa.harvard.edu/abs/1983A%26A...123..263U},
Volume = {123},
Year = {1983},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1983A&A...123..263U}}
@article{volkmer95,
Abstract = {We present a time sequence of spectro-polarimetric measurements of high spatial and spectral resolution. It was obtained in the Fe I 6302A line from a moderately active region near disc centre of the Sun. The observation was performed with a two-dimensional spectrometer which uses a Fabry-Perot interferometer for wavelength scanning and to which a Stokes-V polarimeter was added. This allows us to follow horizontal motions of structures, here of small-scale magnetic elements, to study structural changes, and to measure vertical velocities of the magnetized plasma. In an isolated magnetic feature we find quasi-periodic horizontal motions with 2km/s amplitude and, with high statistical significance, vertical oscillations of 280m/s rms velocity and with periods near 100s. The energy flux in these short-period waves is estimated at 1.6-2.3x10^7^ergxcm-2/s, yet only for this isolated small feature. So the energy supply appears sufficient for chromospheric heating in bright structures of the Ca network, but it falls much below the needs to balance the radiative loss in larger plage areas.},
Annote = {<record><dc:identifier>1995A&A...304L...1V</dc:identifier><dc:title>Short-period waves in small-scale magnetic flux tubes on the Sun.</dc:title><dc:creator>Volkmer, R.</dc:creator><dc:creator>Kneer, F.</dc:creator><dc:creator>Bendlin, C.</dc:creator><dc:source>Astronomy and Astrophysics, v.304, p.L1</dc:source><dc:date>1995-12-01</dc:date><dc:subject>SUN: FACULAE, SUN: MAGNETIC FIELDS, SMALL-SCALE MAGNETIC FLUX TUBES, OSCILLATIONS OF</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1995A%26A...304L...1V</dc:relation><dc:description>We present a time sequence of spectro-polarimetric measurements of high
spatial and spectral resolution. It was obtained in the Fe I 6302A line
from a moderately active region near disc centre of the Sun. The
observation was performed with a two-dimensional spectrometer which uses
a Fabry-Perot interferometer for wavelength scanning and to which a
Stokes-V polarimeter was added. This allows us to follow horizontal
motions of structures, here of small-scale magnetic elements, to study
structural changes, and to measure vertical velocities of the magnetized
plasma. In an isolated magnetic feature we find quasi-periodic
horizontal motions with 2km/s amplitude and, with high statistical
significance, vertical oscillations of 280m/s rms velocity and with
periods near 100s. The energy flux in these short-period waves is
estimated at 1.6-2.3x10^7^ergxcm-2/s, yet only for this isolated small
feature. So the energy supply appears sufficient for chromospheric
heating in bright structures of the Ca network, but it falls much below
the needs to balance the radiative loss in larger plage areas.</dc:description></record>},
Author = {Volkmer, R. and Kneer, F. and Bendlin, C.},
Date = {1995-12-01},
Date-Added = {2007-11-29 16:34:04 +0100},
Date-Modified = {2007-12-18 17:02:26 +0100},
Journal = {\aap},
Keywords = {SUN: FACULAE, SUN: MAGNETIC FIELDS, SMALL-SCALE MAGNETIC FLUX TUBES, OSCILLATIONS OF},
Pages = {1--4},
Title = {{Short-period waves in small-scale magnetic flux tubes on the Sun.}},
Url = {http://adsseeks.cfa.harvard.edu/abs/1995A%26A...304L...1V},
Volume = {304},
Year = {1995},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1995A&A...304L...1V}}
@article{tsiropoula97,
Abstract = {The application of the cloud model to measurements of the contrast as a function of wavelength in the Halpha line has recently enabled us to derive numerical values for various parameters (such as velocity, source function, Doppler width and optical depth) of dark mottles observed near the center of the solar disk. The values of these parameters are used together with the calculations of Poland et al. (1971SPh....18..391P) and Yakovkin and Zel'dina (1975SPh....45..319Y) in order to determine the physical conditions in these structures. Thus population densities at levels 1, 2, 3 (N_1_, N_2_, N_3_), total particle density of hydrogen N_H_, electron density N_e_, electron temperature T_e_, gas pressure, total column mass, mass density and degree of hydrogen ionization can be determined. The values obtained are comparable with estimates obtained for spicules and mottles by different authors in the past and, furthermore, offer the prospect of putting observational constraints on non-LTE two-dimensional modelling of dark mottles observed in the Halpha line which is currently in progress.},
Annote = {<record><dc:identifier>1997A&A...324.1183T</dc:identifier><dc:title>Determination of physical parameters in dark mottles.</dc:title><dc:creator>Tsiropoula, G.</dc:creator><dc:creator>Schmieder, B.</dc:creator><dc:source>Astronomy and Astrophysics, v.324, p.1183-1189</dc:source><dc:date>1997-08-01</dc:date><dc:subject>SUN:CHROMOSPHERE, FINE STRUCTURE, MOTTLES, SPICULES</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1997A%26A...324.1183T</dc:relation><dc:description>The application of the cloud model to measurements of the contrast as a
function of wavelength in the Halpha line has recently enabled us to
derive numerical values for various parameters (such as velocity, source
function, Doppler width and optical depth) of dark mottles observed near
the center of the solar disk. The values of these parameters are used
together with the calculations of Poland et al. (1971SPh....18..391P)
and Yakovkin and Zel'dina (1975SPh....45..319Y) in order to determine
the physical conditions in these structures. Thus population densities
at levels 1, 2, 3 (N_1_, N_2_, N_3_), total particle density of hydrogen
N_H_, electron density N_e_, electron temperature T_e_, gas pressure,
total column mass, mass density and degree of hydrogen ionization can be
determined. The values obtained are comparable with estimates obtained
for spicules and mottles by different authors in the past and,
furthermore, offer the prospect of putting observational constraints on
non-LTE two-dimensional modelling of dark mottles observed in the
Halpha line which is currently in progress.</dc:description></record>},
Author = {Tsiropoula, G. and Schmieder, B.},
Date = {1997-08-01},
Date-Added = {2007-11-29 16:30:56 +0100},
Date-Modified = {2007-12-16 12:05:27 +0100},
Journal = {\aap},
Keywords = {SUN:CHROMOSPHERE, FINE STRUCTURE, MOTTLES, SPICULES},
Pages = {1183--1189},
Title = {Determination of physical parameters in dark mottles.},
Url = {http://adsseeks.cfa.harvard.edu/abs/1997A%26A...324.1183T},
Volume = {324},
Year = {1997},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1997A&A...324.1183T}}
@article{tsiropoula00,
Abstract = {High resolution observations of a sunspot region were obtained on October 3, 1994 with the Multichannel Subtractive Double Pass (MSDP) spectrograph. This instrument installed at the focus of the Vacuum Tower Telescope (VTT) at Tenerife (Canary Islands) operated in the Halpha line. Intensity fluctuations and Doppler shift velocities at several wavelengths were derived over a two dimensional field of view. The observed intensity profiles were matched with theoretical ones using a technique proposed by Tsiropoula et al. 1999, which enables the variation of the source function inside the structures and the derivation of some physical parameters like the source function, the Doppler width, the optical depth and the line-of-sight velocity. This technique was applied to the dark fibrils surrounding the sunspot umbra. Once these parameters are estimated several other parameters can be determined like population densities at levels 1, 2, 3 (N1, N2, N3), total particle density of hydrogen, NH, electron density, Ne, electron temperature, Te, gas pressure, p, total column mass, m, mass density, rho , sound speed, cs etc. Furthermore, using a simple geometrical model we estimated from the line-of-sight velocity the flow velocity along the dark fibrils assuming different sets of inclination angles of the velocity vector with respect to the vertical. We found that there is a flow from the outer edge of the fibrils (in the side of the penumbra), to their inner edge (umbra side), which is consistent to the siphon flow. Moreover, we found a subsonic flow for the entire extent of two of the fibrils considered and for all inclination angle sets, while for one fibril we found a subsonic flow in the outer edge and supersonic velocity in the inner edge for some of the inclination angle sets.},
Annote = {<record><dc:identifier>2000A&A...357..735T</dc:identifier><dc:title>Physical parameters and flows along chromospheric penumbral fibrils</dc:title><dc:creator>Tsiropoula, G.</dc:creator><dc:source>Astronomy and Astrophysics, v.357, p.735-742 (2000)</dc:source><dc:date>2000-05-01</dc:date><dc:subject>SUN: CHROMOSPHERE, SUN: SUNSPOTS</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2000A%26A...357..735T</dc:relation><dc:description>High resolution observations of a sunspot region were obtained on
October 3, 1994 with the Multichannel Subtractive Double Pass (MSDP)
spectrograph. This instrument installed at the focus of the Vacuum Tower
Telescope (VTT) at Tenerife (Canary Islands) operated in the Halpha
line. Intensity fluctuations and Doppler shift velocities at several
wavelengths were derived over a two dimensional field of view. The
observed intensity profiles were matched with theoretical ones using a
technique proposed by Tsiropoula et al. 1999, which enables the
variation of the source function inside the structures and the
derivation of some physical parameters like the source function, the
Doppler width, the optical depth and the line-of-sight velocity. This
technique was applied to the dark fibrils surrounding the sunspot umbra.
Once these parameters are estimated several other parameters can be
determined like population densities at levels 1, 2, 3 (N1,
N2, N3), total particle density of hydrogen,
NH, electron density, Ne, electron temperature,
Te, gas pressure, p, total column mass, m, mass density, rho
, sound speed, cs etc. Furthermore, using a simple
geometrical model we estimated from the line-of-sight velocity the flow
velocity along the dark fibrils assuming different sets of inclination
angles of the velocity vector with respect to the vertical. We found
that there is a flow from the outer edge of the fibrils (in the side of
the penumbra), to their inner edge (umbra side), which is consistent to
the siphon flow. Moreover, we found a subsonic flow for the entire
extent of two of the fibrils considered and for all inclination angle
sets, while for one fibril we found a subsonic flow in the outer edge
and supersonic velocity in the inner edge for some of the inclination
angle sets.</dc:description></record>},
Author = {Tsiropoula, G.},
Date = {2000-05-01},
Date-Added = {2007-11-29 16:30:56 +0100},
Date-Modified = {2007-12-16 12:05:49 +0100},
Journal = {\aap},
Keywords = {SUN: CHROMOSPHERE, SUN: SUNSPOTS},
Pages = {735--742},
Title = {Physical parameters and flows along chromospheric penumbral fibrils},
Url = {http://adsseeks.cfa.harvard.edu/abs/2000A%26A...357..735T},
Volume = {357},
Year = {2000},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2000A&A...357..735T}}
@inproceedings{2007msfa.conf..265T,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/2007msfa.conf..265T},
Author = {{Tothova}, D. and {Innes}, D.~E. and {Solanki}, S.~K.},
Booktitle = {Modern solar facilities - advanced solar science, Proceedings of a Workshop held at G{\"o}ttingen},
Date-Added = {2007-11-29 16:30:00 +0100},
Date-Modified = {2007-12-17 17:32:47 +0100},
Editor = {{Kneer}, F. and {Puschmann}, K.~G. and {Wittmann}, A.~D.},
Pages = {265--268},
Title = {{Wavelet-based method for coronal loop oscillations analysis}},
Year = 2007}
@article{2007Sci...317.1192T,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/2007Sci...317.1192T},
Author = {{Tomczyk}, S. and {McIntosh}, S.~W. and {Keil}, S.~L. and {Judge}, P.~G. and {Schad}, T. and {Seeley}, D.~H. and {Edmondson}, J.},
Date-Added = {2007-11-29 16:29:11 +0100},
Date-Modified = {2007-12-17 17:32:12 +0100},
Doi = {10.1126/science.1143304},
Journal = {Science},
Month = aug,
Pages = {1192--1196},
Title = {{Alfv{\'e}n Waves in the Solar Corona}},
Volume = 317,
Year = 2007,
Bdsk-Url-1 = {http://dx.doi.org/10.1126/science.1143304}}
@inproceedings{1977ASSL...69...97T,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1977ASSL...69...97T},
Author = {{Tandberg-Hanssen}, E.},
Booktitle = {Illustrated Glossary for Solar and Solar-Terrestrial Physics},
Date-Added = {2007-11-29 16:27:29 +0100},
Date-Modified = {2007-12-17 17:31:10 +0100},
Editor = {{Bruzek}, A. and {Durrant}, C.~J.},
Pages = {97--111},
Series = {Astrophysics and Space Science Library},
Title = {{Prominences}},
Volume = 69,
Year = 1977}
@article{1989ApJ...343..985S,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1989ApJ...343..985S},
Author = {{Sterling}, A.~C. and {Hollweg}, J.~V.},
Date-Added = {2007-11-29 16:23:23 +0100},
Date-Modified = {2007-11-29 16:23:23 +0100},
Doi = {10.1086/167767},
Journal = {\apj},
Month = aug,
Pages = {985-993},
Title = {{A rebound shock mechanism for solar fibrils}},
Volume = 343,
Year = 1989,
Bdsk-Url-1 = {http://dx.doi.org/10.1086/167767}}
@article{1982SoPh...75....3S,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1982SoPh...75....3S},
Author = {{Spruit}, H.~C.},
Date-Added = {2007-11-29 16:21:24 +0100},
Date-Modified = {2007-11-29 16:21:24 +0100},
Journal = {\solphys},
Month = jan,
Pages = {3-17},
Title = {{Propagation speeds and acoustic damping of waves in magnetic flux tubes}},
Volume = 75,
Year = 1982}
@article{rouppe07,
Abstract = {We present high spatial and high temporal resolution observations of the quiet Sun in Halpha obtained with the Swedish 1-m Solar Telescope on La Palma. We observe that many mottles, jetlike features in the quiet Sun, display clear up- and downward motions along their main axis. In addition, many mottles show vigorous transverse displacements. Unique identification of the mottles throughout their lifetime is much harder than for their active region counterpart, dynamic fibrils. This is because many seem to lack a sharply defined edge at their top, and significant fading often occurs throughout their lifetime. For those mottles that can be reliably tracked, we find that the mottle tops often undergo parabolic paths. We find a linear correlation between the deceleration these mottles undergo and the maximum velocity they reach, similar to what was found earlier for dynamic fibrils. Combined with an analysis of oscillatory properties, we conclude that at least part of the quiet-Sun mottles are driven by magnetoacoustic shocks. In addition, the mixed-polarity environment and vigorous dynamics suggest that reconnection may play a significant role in the formation of some quiet-Sun jets.},
Annote = {<record><dc:identifier>2007ApJ...660L.169R</dc:identifier><dc:title>Magnetoacoustic Shocks as a Driver of Quiet-Sun Mottles</dc:title><dc:creator>Rouppe van der Voort, L. H. M.</dc:creator><dc:creator>De Pontieu, B.</dc:creator><dc:creator>Hansteen, V. H.</dc:creator><dc:creator>Carlsson, M.</dc:creator><dc:creator>van Noort, M.</dc:creator><dc:source>\apj, Volume 660, Issue 2, pp. L169-L172.</dc:source><dc:date>2007-05-01</dc:date><dc:subject>Sun: Atmospheric Motions, Sun: Chromosphere, Sun: Magnetic Fields</dc:subject><dc:rights>(c) 2007: The American Astronomical Society</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2007ApJ...660L.169R</dc:relation><dc:description>We present high spatial and high temporal resolution observations of the
quiet Sun in Halpha obtained with the Swedish 1-m Solar Telescope on
La Palma. We observe that many mottles, jetlike features in the quiet
Sun, display clear up- and downward motions along their main axis. In
addition, many mottles show vigorous transverse displacements. Unique
identification of the mottles throughout their lifetime is much harder
than for their active region counterpart, dynamic fibrils. This is
because many seem to lack a sharply defined edge at their top, and
significant fading often occurs throughout their lifetime. For those
mottles that can be reliably tracked, we find that the mottle tops often
undergo parabolic paths. We find a linear correlation between the
deceleration these mottles undergo and the maximum velocity they reach,
similar to what was found earlier for dynamic fibrils. Combined with an
analysis of oscillatory properties, we conclude that at least part of
the quiet-Sun mottles are driven by magnetoacoustic shocks. In addition,
the mixed-polarity environment and vigorous dynamics suggest that
reconnection may play a significant role in the formation of some
quiet-Sun jets.</dc:description></record>},
Author = {Rouppe van der Voort, L. H. M. and De Pontieu, B. and Hansteen, V. H. and Carlsson, M. and van Noort, M.},
Date = {2007-05-01},
Date-Added = {2007-11-29 16:16:04 +0100},
Date-Modified = {2007-12-16 12:05:09 +0100},
Journal = {\apj},
Keywords = {Sun: Atmospheric Motions, Sun: Chromosphere, Sun: Magnetic Fields},
Number = {2},
Pages = {169--172},
Title = {Magnetoacoustic Shocks as a Driver of Quiet-Sun Mottles},
Url = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...660L.169R},
Volume = {660},
Year = {2007},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...660L.169R}}
@article{robbrecht01,
Abstract = {On May 13, 1998 the EIT (Extreme ultraviolet Imaging Telescope) on board of SoHO (Solar and Heliospheric Observatory) and TRACE (Transition Region And Coronal Explorer) instruments produced simultaneous high cadence image sequences of the same active region (AR 8218). TRACE achieved a 25 s cadence in the Fe Ix (171 {\AA}) bandpass while EIT achieved a 15 s cadence (operating in ``shutterless mode'', SoHO JOP 80) in the Fe Xii (195 {\AA}) bandpass. These high cadence observations in two complementary wavelengths have revealed the existence of weak transient disturbances in an extended coronal loop system. These propagating disturbances (PDs) seem to be a common phenomenon in this part of the active region. The disturbances originate from small scale brightenings at the footpoints of the loops and propagate along the loops. The projected propagation speeds roughly vary between 65 and 150 km s-1 for both instruments which is close to and below the expected sound speed in the coronal loops. The measured slow magnetoacoustic propagation speeds seem to suggest that the transients are sound (or slow) wave disturbances. This work differs from previous studies in the sense that it is based on a multi-wavelength observation of an entire loop bundle at high cadence by two EUV imagers. The observation of sound waves along the same path shows that they propagate along the same loop, suggesting that loops contain sharp temperature gradients and consist of either concentric shells or thin loop threads, at different temperatures.},
Annote = {<record><dc:identifier>2001A&A...370..591R</dc:identifier><dc:title>Slow magnetoacoustic waves in coronal loops: EIT and TRACE</dc:title><dc:creator>Robbrecht, E.</dc:creator><dc:creator>Verwichte, E.</dc:creator><dc:creator>Berghmans, D.</dc:creator><dc:creator>Hochedez, J. F.</dc:creator><dc:creator>Poedts, S.</dc:creator><dc:creator>Nakariakov, V. M.</dc:creator><dc:source>Astronomy and Astrophysics, v.370, p.591-601 (2001)</dc:source><dc:date>2001-05-01</dc:date><dc:subject>SUN: ACTIVITY, SUN: CORONA, SUN: OSCILLATIONS, SUN: UV RADIATION, MHD, WAVES</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2001A%26A...370..591R</dc:relation><dc:description>On May 13, 1998 the EIT (Extreme ultraviolet Imaging Telescope) on board
of SoHO (Solar and Heliospheric Observatory) and TRACE (Transition
Region And Coronal Explorer) instruments produced simultaneous high
cadence image sequences of the same active region (AR 8218). TRACE
achieved a 25 s cadence in the Fe Ix (171 {\AA}) bandpass while EIT
achieved a 15 s cadence (operating in ``shutterless mode'', SoHO JOP 80)
in the Fe Xii (195 {\AA}) bandpass. These high cadence observations in
two complementary wavelengths have revealed the existence of weak
transient disturbances in an extended coronal loop system. These
propagating disturbances (PDs) seem to be a common phenomenon in this
part of the active region. The disturbances originate from small scale
brightenings at the footpoints of the loops and propagate along the
loops. The projected propagation speeds roughly vary between 65 and 150
km s-1 for both instruments which is close to and below the
expected sound speed in the coronal loops. The measured slow
magnetoacoustic propagation speeds seem to suggest that the transients
are sound (or slow) wave disturbances. This work differs from previous
studies in the sense that it is based on a multi-wavelength observation
of an entire loop bundle at high cadence by two EUV imagers. The
observation of sound waves along the same path shows that they propagate
along the same loop, suggesting that loops contain sharp temperature
gradients and consist of either concentric shells or thin loop threads,
at different temperatures.</dc:description></record>},
Author = {Robbrecht, E. and Verwichte, E. and Berghmans, D. and Hochedez, J. F. and Poedts, S. and Nakariakov, V. M.},
Date = {2001-05-01},
Date-Added = {2007-11-29 16:14:24 +0100},
Date-Modified = {2007-12-18 17:01:31 +0100},
Journal = {\aap},
Keywords = {SUN: ACTIVITY, SUN: CORONA, SUN: OSCILLATIONS, SUN: UV RADIATION, MHD, WAVES},
Pages = {591--601},
Title = {{Slow magnetoacoustic waves in coronal loops: EIT and TRACE}},
Url = {http://adsseeks.cfa.harvard.edu/abs/2001A%26A...370..591R},
Volume = {370},
Year = {2001},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2001A&A...370..591R}}
@article{mousielak07,
Abstract = {Propagation of torsional Alfv{\'e}n waves along magnetic flux tubes has been extensively studied for many years, but no conclusive results regarding the existence of a cutoff frequency for these waves have been obtained. The main purpose of this paper is to derive new wave equations that describe the propagation of linear torsional Alfv{\'e}n waves along thin and isothermal magnetic flux tubes and to use these wave equations to demonstrate that the torsional wave propagation is not affected by any cutoff frequency. It is also shown that this cutoff-free propagation is independent of the different choices of coordinate system and wave variables adopted in previous studies. A brief discussion of the implications of this cutoff-free propagation of torsional tube waves on theories of wave heating of the solar and stellar atmospheres is also given.},
Annote = {<record><dc:identifier>2007ApJ...659..650M</dc:identifier><dc:title>Cutoff-free Propagation of Torsional Alfv{\'e}n Waves along Thin Magnetic Flux Tubes</dc:title><dc:creator>Musielak, Z. E.</dc:creator><dc:creator>Routh, S.</dc:creator><dc:creator>Hammer, R.</dc:creator><dc:source>\apj, Volume 659, Issue 1, pp. 650-654.</dc:source><dc:date>2007-04-01</dc:date><dc:subject>Magnetohydrodynamics: MHD, Stars: Atmospheres, Stars: Late-Type, Waves</dc:subject><dc:rights>(c) 2007: The American Astronomical Society</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2007ApJ...659..650M</dc:relation><dc:description>Propagation of torsional Alfv{\'e}n waves along magnetic flux tubes
has been extensively studied for many years, but no conclusive results
regarding the existence of a cutoff frequency for these waves have been
obtained. The main purpose of this paper is to derive new wave equations
that describe the propagation of linear torsional Alfv{\'e}n waves
along thin and isothermal magnetic flux tubes and to use these wave
equations to demonstrate that the torsional wave propagation is not
affected by any cutoff frequency. It is also shown that this cutoff-free
propagation is independent of the different choices of coordinate system
and wave variables adopted in previous studies. A brief discussion of
the implications of this cutoff-free propagation of torsional tube waves
on theories of wave heating of the solar and stellar atmospheres is also
given.</dc:description></record>},
Author = {Musielak, Z. E. and Routh, S. and Hammer, R.},
Date = {2007-04-01},
Date-Added = {2007-11-29 16:11:07 +0100},
Date-Modified = {2007-12-18 16:50:57 +0100},
Journal = {\apj},
Keywords = {Magnetohydrodynamics: MHD, Stars: Atmospheres, Stars: Late-Type, Waves},
Pages = {650--654},
Title = {{Cutoff-free Propagation of Torsional Alfv{\'e}n Waves along Thin Magnetic Flux Tubes}},
Url = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...659..650M},
Volume = {659},
Year = {2007},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...659..650M}}
@article{Krieg:1999sp,
Abstract = {We analyze spectral scans of narrow-band images across the Na D_2 line. They were obtained from disc centre of the Sun with our Fabry-Perot interferometer (FPI) in the Vacuum Tower Telescope at the Observatorio del Teide. The FPI was set to a bandwidth of 200 mAngstroms FWHM and the spectral stepwidth was 100 mAngstroms. Our aim is to study the variation of the granulation pattern with height in the atmosphere. To achieve high spatial resolution the simultaneously taken broad-band images are restored with speckle methods. With the knowledge of these reconstructed images we were also able to restore the narrow-band images. The formation heights are found from temperature response functions RF_T. In the wings of NaD_2, the response functions for different wavelengths exhibit a substantial overlap in atmospheric heights. Therefore we use linear combinations which allow a better height discrimination. Applying the same combinations to the D_2 images we can visualize the height variation of the granular pattern. The granular intensity fluctuations are a matter of the deep photosphere alone. They disappear at heights of about 100 km (above tau_ {5000}=1).},
Annote = {<record><dc:identifier>1999A&A...343..983K</dc:identifier><dc:title>Height variation of the solar granulation</dc:title><dc:creator>Krieg, J.</dc:creator><dc:creator>Wunnenberg, M.</dc:creator><dc:creator>Kneer, F.</dc:creator><dc:creator>Koschinsky, M.</dc:creator><dc:creator>Ritter, C.</dc:creator><dc:source>Astronomy and Astrophysics, v.343, p.983-989 (1999)</dc:source><dc:date>1999-03-01</dc:date><dc:subject>TECHNIQUES: IMAGE PROCESSING, TECHNIQUES: SPECTROSCOPIC, SUN: GRANULATION, SUN: PHOTOSPHERE</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1999A%26A...343..983K</dc:relation><dc:description>We analyze spectral scans of narrow-band images across the Na D_2 line.
They were obtained from disc centre of the Sun with our Fabry-Perot
interferometer (FPI) in the Vacuum Tower Telescope at the Observatorio
del Teide. The FPI was set to a bandwidth of 200 mAngstroms FWHM and the
spectral stepwidth was 100 mAngstroms. Our aim is to study the variation
of the granulation pattern with height in the atmosphere. To achieve
high spatial resolution the simultaneously taken broad-band images are
restored with speckle methods. With the knowledge of these reconstructed
images we were also able to restore the narrow-band images. The
formation heights are found from temperature response functions RF_T. In
the wings of NaD_2, the response functions for different wavelengths
exhibit a substantial overlap in atmospheric heights. Therefore we use
linear combinations which allow a better height discrimination. Applying
the same combinations to the D_2 images we can visualize the height
variation of the granular pattern. The granular intensity fluctuations
are a matter of the deep photosphere alone. They disappear at heights of
about 100 km (above tau_ {5000}=1).</dc:description></record>},
Author = {Krieg, J. and Wunnenberg, M. and Kneer, F. and Koschinsky, M. and Ritter, C.},
Date = {1999-03-01},
Date-Added = {2007-11-29 16:10:19 +0100},
Date-Modified = {2007-12-16 12:03:52 +0100},
Journal = {\aap},
Keywords = {TECHNIQUES: IMAGE PROCESSING, TECHNIQUES: SPECTROSCOPIC, SUN: GRANULATION, SUN: PHOTOSPHERE},
Pages = {983--989},
Title = {Height variation of the solar granulation},
Url = {http://adsseeks.cfa.harvard.edu/abs/1999A%26A...343..983K},
Volume = {343},
Year = {1999},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1999A&A...343..983K}}
@article{2006A&A...449L..35K,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/2006A%26A...449L..35K},
Author = {{Kukhianidze}, V. and {Zaqarashvili}, T.~V. and {Khutsishvili}, E. },
Date-Added = {2007-11-29 16:08:42 +0100},
Date-Modified = {2007-11-29 16:08:42 +0100},
Doi = {10.1051/0004-6361:200600018},
Eprint = {arXiv:astro-ph/0602534},
Journal = {\aap},
Month = apr,
Pages = {L35-L38},
Title = {{Observation of kink waves in solar spicules}},
Volume = 449,
Year = 2006,
Bdsk-Url-1 = {http://dx.doi.org/10.1051/0004-6361:200600018}}
@proceedings{2005ESASP.596.....I,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/2005ESASP.596.....I},
Booktitle = {Chromospheric and Coronal Magnetic Fields},
Date-Added = {2007-11-29 15:57:53 +0100},
Date-Modified = {2007-12-17 17:27:25 +0100},
Editor = {{Innes}, D.~E. and {Lagg}, A. and {Solanki}, S.~A. and D.~Danesy},
Month = nov,
Series = {ESA Special Publication (CD-ROM)},
Title = {{International Scientific Conference on Chromospheric and Coronal Magnetic Fields}},
Volume = 596,
Year = 2005}
@proceedings{heinzel07,
Abstract = {Not Available},
Annote = {<record><dc:identifier>2007ASPC..368.....H</dc:identifier><dc:title>The Physics of Chromospheric Plasmas</dc:title><dc:creator>Heinzel, P.</dc:creator><dc:creator>Dorotovic, I.</dc:creator><dc:creator>Rutten, R. J.</dc:creator><dc:source>The Physics of Chromospheric Plasmas ASP Conference Series, Vol. 368, Proceedings of the conference held 9-13 October, 2006 at the University of Coimbra in Coimbra, Portugal. Edited by P. Heinzel, I. Dorotovic, and R. J. Rutten. San Francisco: Astronomical Society of the Pacific, 2007.</dc:source><dc:date>2007-05-01</dc:date><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2007ASPC..368.....H</dc:relation><dc:description>Not Available</dc:description></record>},
Date = {2007-05-01},
Date-Added = {2007-11-29 12:25:12 +0100},
Date-Modified = {2007-12-17 16:59:27 +0100},
Editor = {Heinzel, P. and Dorotovic, I. and Rutten, R. J.},
Journal = {The Physics of Chromospheric Plasmas ASP Conference Series},
Number = {368},
Publisher = {ASP Conference Series},
Title = {The Physics of Chromospheric Plasmas},
Url = {http://adsseeks.cfa.harvard.edu/abs/2007ASPC..368.....H},
Year = {2007},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2007ASPC..368.....H}}
@article{hansteen06,
Abstract = {The formation of jets such as dynamic fibrils, mottles, and spicules in the solar chromosphere is one of the most important, but also most poorly understood, phenomena of the Sun's magnetized outer atmosphere. We use extremely high resolution observations from the Swedish 1 m Solar Telescope combined with advanced numerical modeling to show that in active regions these jets are a natural consequence of upwardly propagating slow-mode magnetoacoustic shocks. These shocks form when waves generated by convective flows and global p-mode oscillations in the lower lying photosphere leak upward into the magnetized chromosphere. We find excellent agreement between observed and simulated jet velocities, decelerations, lifetimes, and lengths. Our findings suggest that previous observations of quiet-Sun spicules and mottles may also be interpreted in light of a shock-driven mechanism.},
Annote = {<record><dc:identifier>2006ApJ...647L..73H</dc:identifier><dc:title>Dynamic Fibrils Are Driven by Magnetoacoustic Shocks</dc:title><dc:creator>Hansteen, V. H.</dc:creator><dc:creator>De Pontieu, B.</dc:creator><dc:creator>Rouppe van der Voort, L.</dc:creator><dc:creator>van Noort, M.</dc:creator><dc:creator>Carlsson, M.</dc:creator><dc:source>\apj, Volume 647, Issue 1, pp. L73-L76.</dc:source><dc:date>2006-08-01</dc:date><dc:subject>Magnetic Fields, Sun: Chromosphere, Sun: Photosphere</dc:subject><dc:rights>(c) 2006: The American Astronomical Society</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2006ApJ...647L..73H</dc:relation><dc:description>The formation of jets such as dynamic fibrils, mottles, and spicules in
the solar chromosphere is one of the most important, but also most
poorly understood, phenomena of the Sun's magnetized outer atmosphere.
We use extremely high resolution observations from the Swedish 1 m Solar
Telescope combined with advanced numerical modeling to show that in
active regions these jets are a natural consequence of upwardly
propagating slow-mode magnetoacoustic shocks. These shocks form when
waves generated by convective flows and global p-mode oscillations in
the lower lying photosphere leak upward into the magnetized
chromosphere. We find excellent agreement between observed and simulated
jet velocities, decelerations, lifetimes, and lengths. Our findings
suggest that previous observations of quiet-Sun spicules and mottles may
also be interpreted in light of a shock-driven mechanism.</dc:description></record>},
Author = {Hansteen, V. H. and De Pontieu, B. and Rouppe van der Voort, L. and van Noort, M. and Carlsson, M.},
Date = {2006-08-01},
Date-Added = {2007-11-29 12:24:19 +0100},
Date-Modified = {2007-12-16 11:49:08 +0100},
Journal = {\apj},
Keywords = {Magnetic Fields, Sun: Chromosphere, Sun: Photosphere},
Pages = {73--76},
Title = {Dynamic Fibrils Are Driven by Magnetoacoustic Shocks},
Url = {http://adsseeks.cfa.harvard.edu/abs/2006ApJ...647L..73H},
Volume = {647},
Year = {2006},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2006ApJ...647L..73H}}
@article{1975SoPh...44..299G,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/1975SoPh...44..299G},
Author = {{Giovanelli}, R.},
Date-Added = {2007-11-29 12:23:41 +0100},
Date-Modified = {2007-11-29 12:23:41 +0100},
Journal = {\solphys},
Month = oct,
Pages = {299-314},
Title = {{Wave systems in the chromosphere}},
Volume = 44,
Year = 1975}
@article{Wijn:2006ij,
Abstract = {Aims.To study the interaction of the solar chromosphere with the transition region, in particular active-region jets in the transition region and their relation to chromospheric fibrils. Methods: .We carefully align image sequences taken simultaneously in C iv with the Transition Region and Coronal Explorer and in Halpha with the Swedish 1-m Solar Telescope. We examine the temporal evolution of "dynamic fibrils", i.e., individual short-lived active-region chromospheric jet-like features in Halpha. Results: .All dynamic fibrils appear as absorption features in Halpha that progress from the blue to the red wing through the line, and often show recurrent behavior. Some of them, but not all, appear also as bright features in C iv which develop at or just beyond the apex of the Halpha darkening. They tend to best resemble the Halpha fibril at +700 m{\AA} half a minute earlier. Conclusions: .Dynamic chromospheric fibrils observed in Halpha regularly correspond to transition-region jets observed in the ultraviolet. This correspondence suggests that some plasma associated with dynamic fibrils is heated to transition-region temperatures.},
Annote = {<record><dc:identifier>2006A&A...460..309D</dc:identifier><dc:title>Dynamic fibrils in Halpha and C IV</dc:title><dc:creator>de Wijn, A. G.</dc:creator><dc:creator>De Pontieu, B.</dc:creator><dc:source>Astronomy and Astrophysics, Volume 460, Issue 1, December II 2006, pp.309-316</dc:source><dc:date>2006-12-01</dc:date><dc:subject>Sun: chromosphere, Sun: transition region, Sun: UV radiation</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2006A%26A...460..309D</dc:relation><dc:description>Aims.To study the interaction of the solar chromosphere with the
transition region, in particular active-region jets in the transition
region and their relation to chromospheric fibrils. Methods: .We
carefully align image sequences taken simultaneously in C iv with the
Transition Region and Coronal Explorer and in Halpha with the Swedish
1-m Solar Telescope. We examine the temporal evolution of "dynamic
fibrils", i.e., individual short-lived active-region chromospheric
jet-like features in Halpha. Results: .All dynamic fibrils
appear as absorption features in Halpha that progress from the blue to
the red wing through the line, and often show recurrent behavior. Some
of them, but not all, appear also as bright features in C iv which
develop at or just beyond the apex of the Halpha darkening. They tend
to best resemble the Halpha fibril at +700 m{\AA} half a minute
earlier. Conclusions: .Dynamic chromospheric fibrils observed in
Halpha regularly correspond to transition-region jets observed in the
ultraviolet. This correspondence suggests that some plasma associated
with dynamic fibrils is heated to transition-region temperatures.</dc:description></record>},
Author = {de Wijn, A. G. and De Pontieu, B.},
Date = {2006-12-01},
Date-Added = {2007-11-29 12:14:43 +0100},
Date-Modified = {2007-12-16 12:07:19 +0100},
Journal = {\aap},
Keywords = {Sun: chromosphere, Sun: transition region, Sun: UV radiation},
Pages = {309--316},
Title = {Dynamic fibrils in Halpha and C IV},
Url = {http://adsseeks.cfa.harvard.edu/abs/2006A%26A...460..309D},
Volume = {460},
Year = {2006},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2006A&A...460..309D}}
@article{2007ApJ...655..624D,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/2007ApJ...655..624D},
Author = {{De Pontieu}, B. and {Hansteen}, V.~H. and {Rouppe van der Voort}, L. and {van Noort}, M. and {Carlsson}, M.},
Date-Added = {2007-11-29 12:14:15 +0100},
Date-Modified = {2007-11-29 12:14:15 +0100},
Doi = {10.1086/509070},
Eprint = {arXiv:astro-ph/0701786},
Journal = {\apj},
Month = jan,
Pages = {624-641},
Title = {{High-Resolution Observations and Modeling of Dynamic Fibrils}},
Volume = 655,
Year = 2007,
Bdsk-Url-1 = {http://dx.doi.org/10.1086/509070}}
@article{2004Natur.430..536D,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/2004Natur.430..536D},
Author = {{De Pontieu}, B. and {Erd{\'e}lyi}, R. and {James}, S.~P.},
Date-Added = {2007-11-29 12:11:42 +0100},
Date-Modified = {2007-12-16 11:47:39 +0100},
Doi = {10.1038/nature02749},
Journal = {\nat},
Month = jul,
Pages = {536--539},
Title = {{Solar chromospheric spicules from the leakage of photospheric oscillations and flows}},
Volume = 430,
Year = 2004,
Bdsk-Url-1 = {http://dx.doi.org/10.1038/nature02749}}
@article{2002A&A...387L..13D,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/2002A%26A...387L..13D},
Author = {{De Moortel}, I. and {Ireland}, J. and {Hood}, A.~W. and {Walsh}, R.~W. },
Date-Added = {2007-11-29 12:08:41 +0100},
Date-Modified = {2007-12-16 11:47:05 +0100},
Doi = {10.1051/0004-6361:20020436},
Journal = {\aap},
Month = may,
Pages = {13--16},
Title = {{The detection of 3\& 5 min period oscillations in coronal loops}},
Volume = 387,
Year = 2002,
Bdsk-Url-1 = {http://dx.doi.org/10.1051/0004-6361:20020436}}
@article{defouw76,
Abstract = {Motivated by the filamentary structure of solar magnetic fields, this paper considers the propagation of quasi-longitudinal waves along a slender magnetic tube in pressure equilibrium with the ambient medium. The velocity of such waves is expressed in terms of the Alven speed and the sound speed inside the tube. The divergence of a vertical magnetic tube in a stratified atmosphere introduces a critical frequency below which propagation is impossible.},
Annote = {<record><dc:identifier>1976ApJ...209..266D</dc:identifier><dc:title>Wave propagation along a magnetic tube</dc:title><dc:creator>Defouw, R. J.</dc:creator><dc:source>\apj, vol. 209, Oct. 1, 1976, pt. 1, p. 266-269.</dc:source><dc:date>1976-10-01</dc:date><dc:subject>LONGITUDINAL WAVES, MAGNETIC FIELD CONFIGURATIONS, SOLAR ATMOSPHERE, SOLAR GRANULATION, SOLAR MAGNETIC FIELD, ATMOSPHERIC STRATIFICATION, CRITICAL FREQUENCIES, FILAMENTS, MAGNETOHYDRODYNAMIC WAVES, PROPAGATION VELOCITY, SOLAR PHYSICS</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1976ApJ...209..266D</dc:relation><dc:description>Motivated by the filamentary structure of solar magnetic fields, this
paper considers the propagation of quasi-longitudinal waves along a
slender magnetic tube in pressure equilibrium with the ambient medium.
The velocity of such waves is expressed in terms of the Alven speed and
the sound speed inside the tube. The divergence of a vertical magnetic
tube in a stratified atmosphere introduces a critical frequency below
which propagation is impossible.</dc:description></record>},
Author = {Defouw, R. J.},
Date = {1976-10-01},
Date-Added = {2007-11-29 12:03:09 +0100},
Date-Modified = {2007-12-07 15:32:12 +0100},
Journal = {\apj},
Keywords = {LONGITUDINAL WAVES, MAGNETIC FIELD CONFIGURATIONS, SOLAR ATMOSPHERE, SOLAR GRANULATION, SOLAR MAGNETIC FIELD, ATMOSPHERIC STRATIFICATION, CRITICAL FREQUENCIES, FILAMENTS, MAGNETOHYDRODYNAMIC WAVES, PROPAGATION VELOCITY, SOLAR PHYSICS},
Number = {1},
Pages = {266--269},
Title = {Wave propagation along a magnetic tube},
Url = {http://adsseeks.cfa.harvard.edu/abs/1976ApJ...209..266D},
Volume = {209},
Year = {1976},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1976ApJ...209..266D}}
@article{choudhuri93,
Abstract = {It is argued that the photospheric footpoints of coronal magnetic field lines could have a profound impact on the heating of the quiet corona. A mathematical analysis is carried out to examine the response of a vertical thin flux tube to photospheric footpoint motions in terms of a superposition of linear kink modes for an isothermal atmosphere. The resulting total energy that is asymptotically injected into an isothermal atmosphere, i.e., an atmosphere without any back reflection, is found. Typical parameter values for fast and slow footpoint motions are used to show that, even if the footpoints spend only 2.5 percent of the time undergoing rapid motions, these rapid motions could be more efficient in transporting energy to the corona than the slow motions that take place most of the time.},
Annote = {<record><dc:identifier>1993SoPh..143...49C</dc:identifier><dc:title>Implications of rapid footpoint motions of photospheric flux tubes for coronal heating</dc:title><dc:creator>Choudhuri, Arnab R.</dc:creator><dc:creator>Auffret, Herve</dc:creator><dc:creator>Priest, Eric R.</dc:creator><dc:source>Solar Physics (ISSN 0038-0938), vol. 143, no. 1, p. 49-68.</dc:source><dc:date>1993-01-01</dc:date><dc:subject>PHOTOSPHERE, SOLAR CORONA, SOLAR MAGNETIC FIELD, SOLAR PHYSICS, ENERGY TRANSFER, ISOTHERMAL PROCESSES, MAGNETIC FLUX, MATHEMATICAL MODELS</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1993SoPh..143...49C</dc:relation><dc:description>It is argued that the photospheric footpoints of coronal magnetic field
lines could have a profound impact on the heating of the quiet corona. A
mathematical analysis is carried out to examine the response of a
vertical thin flux tube to photospheric footpoint motions in terms of a
superposition of linear kink modes for an isothermal atmosphere. The
resulting total energy that is asymptotically injected into an
isothermal atmosphere, i.e., an atmosphere without any back reflection,
is found. Typical parameter values for fast and slow footpoint motions
are used to show that, even if the footpoints spend only 2.5 percent of
the time undergoing rapid motions, these rapid motions could be more
efficient in transporting energy to the corona than the slow motions
that take place most of the time.</dc:description></record>},
Author = {Choudhuri, Arnab R. and Auffret, Herve and Priest, Eric R.},
Date = {1993-01-01},
Date-Added = {2007-11-29 12:02:10 +0100},
Date-Modified = {2007-12-07 15:31:40 +0100},
Journal = {\solphys},
Keywords = {PHOTOSPHERE, SOLAR CORONA, SOLAR MAGNETIC FIELD, SOLAR PHYSICS, ENERGY TRANSFER, ISOTHERMAL PROCESSES, MAGNETIC FLUX, MATHEMATICAL MODELS},
Number = {1},
Pages = {49--68},
Title = {Implications of rapid footpoint motions of photospheric flux tubes for coronal heating},
Url = {http://adsseeks.cfa.harvard.edu/abs/1993SoPh..143...49C},
Volume = {143},
Year = {1993},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1993SoPh..143...49C}}
@inproceedings{carlsson05,
Abstract = {Not Available},
Annote = {<record><dc:identifier>2005ESASP.596E..39C</dc:identifier><dc:title>Chromospheric Waves</dc:title><dc:creator>Carlsson, M.</dc:creator><dc:creator>Hansteen, V.</dc:creator><dc:source>Proceedings of the International Scientific Conference on Chromospheric and Coronal Magnetic Fields (ESA SP-596). 30 August - 2 September 2005, Katlenburg-Lindau, Germany. Editors: D.E. Innes, A. Lagg & S.K. Solanki, Published on CDROM, p.39.1</dc:source><dc:date>2005-11-01</dc:date><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2005ESASP.596E..39C</dc:relation><dc:description>Not Available</dc:description></record>},
Author = {Carlsson, M. and Hansteen, V.},
Booktitle = {International Scientific Conference on Chromospheric and Coronal Magnetic Fields (ESA SP-596) on CD-Rom},
Date = {2005-11-01},
Date-Added = {2007-11-29 11:58:27 +0100},
Date-Modified = {2007-12-16 11:45:27 +0100},
Editor = {D.E. Innes and A. Lagg and S.K. Solanki and D. Danesy},
Title = {Chromospheric Waves},
Url = {http://adsseeks.cfa.harvard.edu/abs/2005ESASP.596E..39C},
Year = {2005},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2005ESASP.596E..39C}}
@article{Bello-Gonzalez:2005kl,
Abstract = {We present two-dimensional high-spatial-resolution spectropolarimetric observations of sunspot penumbrae. They were obtained in April 2002 and May 2003 with the "G{\"o}ttingen" Fabry-P{\'e}rot spectrometer at the Vacuum Tower Telescope at the Observatorio del Teide (Tenerife). Speckle methods were applied for image reconstruction which resulted in a spatial resolution of 0.5 arcsec in the magnetograms of the penumbrae. We analysed Stokes I and V profiles of the Fe II 6149 {\AA} line, which exhibits no instrumental Stokes Q/U--> V crosstalk, and of the Fe I line pair at 6302 {\AA}. The main results are the following: 1) on scales larger than 0.5 arcsec, the intensity pattern of penumbrae stays the same in the continuum and core images of the 6301.5 {\AA} line, which stem from 0 km and 300 km (above tau_5=1), respectively. Yet at scales of 0.5 arcsec and smaller the pattern in the two spectral features is clearly different. 2) On the limb side of sunspots the Evershed flow is carried by dark filaments and on the centre side by bright features and their somewhat weakened tails. We explain this with a picture in which the velocity of hot rising gas is best seen on the centre side, while on the limb side the horizontal outward and possibly downward flows are seen when the gas has cooled down. 3) The un-combed structure of the magnetic field is confirmed. On the limb side, the more horizontal fields coincide with dark fibrils or with diffuse intensity structures. Generally, the more horizontal fields are located at the positions of strong outflows. 4) Strong line-of-sight components of the magnetic fields are not found in bright filaments but in dark structures, somewhat displaced from the darkest parts. Their positions do not coincide with those of the strongest velocity fields. In general, our results are compatible with the picture of low lying flow channels coincident with the horizontal magnetic field, or possibly emerging and diving down into sub-photospheric layers, like a "sea serpent". Some further dynamic phenomena are discussed, which demonstrate the richness of processes in penumbrae, and reveal unexpected properties.},
Annote = {<record><dc:identifier>2005A&A...434..317B</dc:identifier><dc:title>Polarimetry of sunspot penumbrae with high spatial resolution</dc:title><dc:creator>Bello Gonz{\'a}lez, N.</dc:creator><dc:creator>Okunev, O. V.</dc:creator><dc:creator>Dom{\'\i}nguez Cerde{\~n}a, I.</dc:creator><dc:creator>Kneer, F.</dc:creator><dc:creator>Puschmann, K. G.</dc:creator><dc:source>Astronomy and Astrophysics, Volume 434, Issue 1, April IV 2005, pp.317-327</dc:source><dc:date>2005-04-01</dc:date><dc:subject>Sun: sunspots, Sun: magnetic fields, techniques: high angular resolution</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2005A%26A...434..317B</dc:relation><dc:description>We present two-dimensional high-spatial-resolution spectropolarimetric
observations of sunspot penumbrae. They were obtained in April 2002 and
May 2003 with the "G{\"o}ttingen" Fabry-P{\'e}rot spectrometer at
the Vacuum Tower Telescope at the Observatorio del Teide (Tenerife).
Speckle methods were applied for image reconstruction which resulted in
a spatial resolution of 0.5 arcsec in the magnetograms of the penumbrae.
We analysed Stokes I and V profiles of the Fe II 6149 {\AA} line,
which exhibits no instrumental Stokes Q/U--> V crosstalk, and of the
Fe I line pair at 6302 {\AA}. The main results are the following: 1)
on scales larger than 0.5 arcsec, the intensity pattern of penumbrae
stays the same in the continuum and core images of the 6301.5 {\AA}
line, which stem from 0 km and 300 km (above tau_5=1), respectively.
Yet at scales of 0.5 arcsec and smaller the pattern in the two spectral
features is clearly different. 2) On the limb side of sunspots the
Evershed flow is carried by dark filaments and on the centre side by
bright features and their somewhat weakened tails. We explain this with
a picture in which the velocity of hot rising gas is best seen on the
centre side, while on the limb side the horizontal outward and possibly
downward flows are seen when the gas has cooled down. 3) The un-combed
structure of the magnetic field is confirmed. On the limb side, the more
horizontal fields coincide with dark fibrils or with diffuse intensity
structures. Generally, the more horizontal fields are located at the
positions of strong outflows. 4) Strong line-of-sight components of the
magnetic fields are not found in bright filaments but in dark
structures, somewhat displaced from the darkest parts. Their positions
do not coincide with those of the strongest velocity fields. In general,
our results are compatible with the picture of low lying flow channels
coincident with the horizontal magnetic field, or possibly emerging and
diving down into sub-photospheric layers, like a "sea serpent". Some
further dynamic phenomena are discussed, which demonstrate the richness
of processes in penumbrae, and reveal unexpected properties.</dc:description></record>},
Author = {Bello Gonz{\'a}lez, N. and Okunev, O. V. and Dom{\'\i}nguez Cerde{\~n}a, I. and Kneer, F. and Puschmann, K. G.},
Date = {2005-04-01},
Date-Added = {2007-11-29 11:31:54 +0100},
Date-Modified = {2007-12-16 12:03:07 +0100},
Journal = {\aap},
Keywords = {Sun: sunspots, Sun: magnetic fields, techniques: high angular resolution},
Pages = {317--327},
Title = {Polarimetry of sunspot penumbrae with high spatial resolution},
Url = {http://adsseeks.cfa.harvard.edu/abs/2005A%26A...434..317B},
Volume = {434},
Year = {2005},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2005A&A...434..317B}}
@article{beckers69,
Abstract = {Abstract image available at: http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..351B},
Annote = {<record><dc:identifier>1969SoPh....7..351B</dc:identifier><dc:title>Chromospheric Inhomogeneities in Sunspot Umbrae</dc:title><dc:creator>Beckers, Jacques M.</dc:creator><dc:creator>Tallant, Paul E.</dc:creator><dc:source>Solar Physics, Volume 7, Issue 3, pp.351-365</dc:source><dc:date>1969-06-01</dc:date><dc:rights>(c) 1969: D. Reidel Publishing Company</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..351B</dc:relation><dc:description>Abstract image available at:
http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..351B</dc:description></record>},
Author = {Beckers, Jacques M. and Tallant, Paul E.},
Date = {1969-06-01},
Date-Added = {2007-11-29 11:29:47 +0100},
Date-Modified = {2007-12-07 15:29:21 +0100},
Journal = {\solphys},
Number = {3},
Pages = {351--365},
Title = {Chromospheric Inhomogeneities in Sunspot Umbrae},
Url = {http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..351B},
Volume = {7},
Year = {1969},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1969SoPh....7..351B}}
@article{athay76,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1977P%26SS...25..893J},
Author = {Athay, R. G.},
Date-Added = {2007-11-29 11:24:46 +0100},
Date-Modified = {2007-12-06 13:01:27 +0100},
Doi = {10.1016/0032-0633(77)90045-9},
Journal = {Reidel, Dordrecht},
Number = {504},
Title = {{The solar chromosphere and corona: Quiet Sun}},
Volume = {XII},
Year = 1976,
Bdsk-Url-1 = {http://dx.doi.org/10.1016/0032-0633(77)90045-9}}
@article{1992A&A...264..236G,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://cdsads.u-strasbg.fr/abs/1992A%26A...264..236G},
Author = {{Grossmann-Doerth}, U. and {Schmidt}, W.},
Date-Added = {2007-11-26 21:22:57 +0100},
Date-Modified = {2007-11-26 21:22:57 +0100},
Journal = {\aap},
Month = oct,
Pages = {236-242},
Title = {{Chromospheric fine structure revisited}},
Volume = 264,
Year = 1992}
@book{bray74,
Author = {Bray, R. J. and Loughhead, R. E.},
Booktitle = {{The Solar Chromosphere}},
Date-Added = {2007-11-22 19:05:59 +0100},
Date-Modified = {2007-11-22 19:07:04 +0100},
Publisher = {Chapman and Hall, London},
Title = {{The Solar Chromosphere}},
Year = {1974}}
@book{priest84,
Author = {Priest, E. R.},
Booktitle = {Solaer},
Date-Added = {2007-11-22 18:29:10 +0100},
Date-Modified = {2007-11-22 18:33:36 +0100},
Publisher = {Reidel, Dortrecht},
Title = {Solar Magnetohydrodynamics},
Year = {1984}}
@book{kippenhahn75,
Author = {Kippenhahn, R. and {M\"ollenhoff}, C.},
Booktitle = {Elementare Plasmaphysik},
Date-Added = {2007-11-22 18:26:47 +0100},
Date-Modified = {2007-11-22 18:28:51 +0100},
Publisher = {Bibliograpisches Institut, {Z\"urich}},
Title = {Elementare Plasmaphysik},
Year = {1975}}
@book{ferraro66,
Author = {Ferraro, V. C. A. and Plumpton, A.},
Booktitle = {An Introduction to {Magneto-Fluid Mechanics}},
Date-Added = {2007-11-22 18:23:54 +0100},
Date-Modified = {2007-11-22 18:26:02 +0100},
Publisher = {Oxford University Press, Oxford},
Title = {An Introduction to {Magneto-Fluid Mechanics}},
Year = {1966}}
@inproceedings{avrett95,
Abstract = {One-dimensional hydrostatic models of quiet and active solar regions can be constructed that generally account for the observed intensities of lines and continua throughout the spectrum, except for the infrared CO lines. There is an apparent conflict between a) observations of the strongest infrared CO lines formed in LTE at low-chromospheric heights but at temperatures much cooler than the average chromospheric values, and b) observations of Ca II, UV, and microwave intensities that originate from the same chromospheric heights but at the much higher temperatures characteristic of the average chromosphere. A model M_CO has been constructed which gives a good fit to the full range of mean CO line profiles (averaged over the central area of the solar disk and over time) but this model conflicts with other observations of average quiet regions. A model L_CO which is approximately 100 K cooler than M_CO combined with a very bright network model F in the proportions 0.6L_CO+0.4F is found to be generally consistent with the CO, Ca II, UV, and microwave observations. Ayres, Testerman, and Brault found that models COOLC and FLUXT in the proportions 0.925 and 0.075 account for the CO and Ca II lines, but these combined models give an average UV intensity at 140 nm about 20 times larger than observed. The 0.6L_CO+0.4F result may give a better description of the cool and hot components that produce the space- and time-averaged spectra. Recent observations carried out by Uitenbroek, Noyes, and Rabin with high spatial and temporal resolution indicate that the faintest intensities in the strong CO lines measured at given locations usually become much brighter within 1 to 3 minutes. The cool regions thus seem to be mostly the low- temperature portions of oscillatory waves rather than cool structures that are stationary.},
Author = {Avrett, E. H.},
Booktitle = {Infrared Tools for Solar Astrophysics: What's Next?, 15th NSO Sac Peak Workshop},
Date = {1995-00-01},
Date-Added = {2007-11-16 15:46:21 +0100},
Date-Modified = {2007-12-16 11:34:45 +0100},
Editor = { J. Kuhn and M. Penn},
Pages = {303--311},
Title = {Two-Component Modeling of the Solar {IR CO} Lines},
Url = {http://adsseeks.cfa.harvard.edu/abs/1995itsa.conf..303A},
Year = {1995},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1995itsa.conf..303A}}
@article{beckers68,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1968SoPh....3..367B},
Author = {{Beckers}, J.~M.},
Date-Added = {2007-11-16 15:45:45 +0100},
Date-Modified = {2007-11-16 15:51:00 +0100},
Doi = {10.1007/BF00171614},
Journal = {\solphys},
Month = mar,
Pages = {367-433},
Title = {{Solar Spicules (Invited Review Paper)}},
Volume = 3,
Year = 1968,
Bdsk-Url-1 = {http://dx.doi.org/10.1007/BF00171614}}
@article{beckers72,
Adsnote = {Provided by the Smithsonian/NASA Astrophysics Data System},
Adsurl = {http://adsabs.harvard.edu/abs/1972ARA%26A..10...73B},
Author = {{Beckers}, J.~M.},
Date-Added = {2007-11-16 15:45:02 +0100},
Date-Modified = {2007-12-07 12:27:59 +0100},
Doi = {10.1146/annurev.aa.10.090172.000445},
Journal = {\araa},
Pages = {73--100},
Title = {{Solar Spicules}},
Volume = 10,
Year = 1972,
Bdsk-Url-1 = {http://dx.doi.org/10.1146/annurev.aa.10.090172.000445}}
@phdthesis{Centeno06,
Author = {{Centeno}, R.},
Date-Added = {2007-11-16 15:41:32 +0100},
Date-Modified = {2007-12-18 15:42:57 +0100},
School = {Universidad de La Laguna},
Title = {Investigaci\'on de la propagaci\'on de ondas en la atm\'osfera solar mediante espectropolarimetr\'ia en Helio I 10830 \AA},
Year = {2006}}
@article{fontenla91,
Abstract = {The radiation of energy by hydrogen lines and continua in hydrostatic energy-balance models of the transition region between the solar chromosphere and corona is studied using models which assume that mechanical or magnetic energy is dissipated in the hot corona and is then transported toward the chromosphere down the steep temperature gradient of the transition region. These models explain the average quiet sun and also the entire range of variability of the Ly-alpha lines. The relations between the downward energy flux, the pressure of the transition region, and the different hydrogen emission are described.},
Annote = {<record><dc:identifier>1991ApJ...377..712F</dc:identifier><dc:title>Energy balance in the solar transition region. II - Effects of pressure and energy input on hydrostatic models</dc:title><dc:creator>Fontenla, J. M.</dc:creator><dc:creator>Avrett, E. H.</dc:creator><dc:creator>Loeser, R.</dc:creator><dc:source>\apj, Part 1 (ISSN 0004-637X), vol. 377, Aug. 20, 1991, p. 712-725.</dc:source><dc:date>1991-08-01</dc:date><dc:subject>CHROMOSPHERE, LINE SPECTRA, RADIATIVE TRANSFER, SOLAR ATMOSPHERE, SOLAR CORONA, SOLAR SPECTRA, BOUNDARY CONDITIONS, H LINES, HYDROSTATICS, STELLAR MODELS</dc:subject><dc:relation>http://adsseeks.cfa.harvard.edu/abs/1991ApJ...377..712F</dc:relation><dc:description>The radiation of energy by hydrogen lines and continua in hydrostatic
energy-balance models of the transition region between the solar
chromosphere and corona is studied using models which assume that
mechanical or magnetic energy is dissipated in the hot corona and is
then transported toward the chromosphere down the steep temperature
gradient of the transition region. These models explain the average
quiet sun and also the entire range of variability of the Ly-alpha
lines. The relations between the downward energy flux, the pressure of
the transition region, and the different hydrogen emission are
described.</dc:description></record>},
Author = {Fontenla, J. M. and Avrett, E. H. and Loeser, R.},
Date = {1991-08-01},
Date-Added = {2007-11-16 15:33:47 +0100},
Date-Modified = {2007-11-20 15:13:51 +0100},
Journal = {\apj},
Keywords = {CHROMOSPHERE, LINE SPECTRA, RADIATIVE TRANSFER, SOLAR ATMOSPHERE, SOLAR CORONA, SOLAR SPECTRA, BOUNDARY CONDITIONS, H LINES, HYDROSTATICS, STELLAR MODELS},
Pages = {712-725},
Title = {Energy balance in the solar transition region. {II} - Effects of pressure and energy input on hydrostatic models},
Url = {http://adsseeks.cfa.harvard.edu/abs/1991ApJ...377..712F},
Volume = {377},
Year = {1991},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/1991ApJ...377..712F}}
@article{hegg07,
Abstract = {We present the results of numerical simulations of shock wave-driven jets in the solar atmosphere. The dependence of observable quantities such as maximum velocity and deceleration on parameters such as the period and amplitude of initial disturbances and the inclination of the magnetic field is investigated. Our simulations show excellent agreement with observations, and shed new light on the correlation between velocity and deceleration and on the regional differences found in observations.},
Annote = {<record><dc:identifier>2007ApJ...666.1277H</dc:identifier><dc:title>Numerical Simulations of Shock Wave-driven Chromospheric Jets</dc:title><dc:creator>Heggland, L.</dc:creator><dc:creator>De Pontieu, B.</dc:creator><dc:creator>Hansteen, V. H.</dc:creator><dc:source>\apj, Volume 666, Issue 2, pp. 1277-1283.</dc:source><dc:date>2007-09-01</dc:date><dc:subject>Magnetic Fields, Magnetohydrodynamics: MHD, Shock Waves, Sun: Chromosphere</dc:subject><dc:rights>(c) 2007: The American Astronomical Society</dc:rights><dc:relation>http://adsseeks.cfa.harvard.edu/abs/2007ApJ...666.1277H</dc:relation><dc:description>We present the results of numerical simulations of shock wave-driven
jets in the solar atmosphere. The dependence of observable quantities
such as maximum velocity and deceleration on parameters such as the
period and amplitude of initial disturbances and the inclination of the
magnetic field is investigated. Our simulations show excellent agreement
with observations, and shed new light on the correlation between
velocity and deceleration and on the regional differences found in
observations.</dc:description></record>},
Author = {Heggland, L. and De Pontieu, B. and Hansteen, V. H.},
Date = {2007-09-01},
Date-Added = {2007-11-16 15:33:11 +0100},
Date-Modified = {2007-11-20 15:13:38 +0100},
Journal = {\apj},
Keywords = {Magnetic Fields, Magnetohydrodynamics: MHD, Shock Waves, Sun: Chromosphere},
Number = {2},
Pages = {1277-1283},
Title = {Numerical Simulations of Shock Wave-driven Chromospheric Jets},
Url = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...666.1277H},
Volume = {666},
Year = {2007},
Bdsk-Url-1 = {http://adsseeks.cfa.harvard.edu/abs/2007ApJ...666.1277H}}
@article{secchi1877,
Author = {Secchi, P.A.},
Date-Added = {2007-11-16 15:30:49 +0100},
Date-Modified = {2007-11-16 15:31:39 +0100},
Journal = {{\it Le Soleil}},