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Related papers: Linear wavelength correlation matrices of photosph…

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We tested whether simultaneous spectropolarimetric imaging in two magnetically sensitive optical spectral lines, which probe two different layers of the solar atmosphere (the photosphere and the temperature minimum), can help constrain the…

The importance of magnetic fields in three-dimensional magnetoconvection models of the Sun's photosphere is investigated in terms of their influence on the continuum intensity at different viewing inclination angles, and on the intensity…

Solar and Stellar Astrophysics · Physics 2015-06-23 D. Fabbian , F. Moreno-Insertis

We study the local response to long wavelength fluctuations in cosmological $N$-body simulations, focusing on the matter and halo power spectra, halo abundance and non-linear transformations of the density field. The long wavelength mode is…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Tobias Baldauf , Uroš Seljak , Leonardo Senatore , Matias Zaldarriaga

We have investigated the effects of resonant scattering of emission lines on the image morphology and intensity from coronal loop structures. It has previously been shown that line of sight effects in optically thin line emission can yield…

Astrophysics · Physics 2009-10-31 Kenneth Wood , John Raymond

Recently, new solar model atmospheres have been developed to replace classical 1D LTE hydrostatic models and used to for example derive the solar chemical composition. We aim to test various models against key observational constraints. In…

Solar and Stellar Astrophysics · Physics 2015-06-15 Tiago M. D. Pereira , Martin Asplund , Remo Collet , Irina Thaler , Regner Trampedach , Jorrit Leenaarts

Aims. With the Solar Optical Telescope on Hinode, we investigate the basic properties of high-degree solar oscillations observed at two levels in the solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H line…

Astrophysics · Physics 2009-11-13 U. Mitra-Kraev , A. G. Kosovichev , T. Sekii

On 12 March 1996 we obtained observations of the quiet Sun with the SUMER instrument. The observa- tions were sequences of 15-20 second exposures of ultraviolet emission line profiles and of the neighboring continua. These data contain…

Astrophysics · Physics 2009-10-30 Mats Carlsson , Philip G. Judge , Klaus Wilhelm

We use a combination of analytical theory, numerical simulation, and data analysis to study the propagation of acoustic waves along coronal loops. We show that the intensity perturbation of a wave depends on a number of factors, including…

Astrophysics · Physics 2009-11-10 J. A. Klimchuk , S. E. M. Tanner , I. De Moortel

In this paper we discuss two approximate methods previously suggested for modeling hyperfine spectral line emission for molecules whose collisional transitions rates between hyperfine levels are unknown. Hyperfine structure is seen in the…

Astrophysics of Galaxies · Physics 2015-05-18 Eric Keto , George Rybicki

CHROMIS, a new imaging spectrometer at the Swedish 1-m Solar Telescope (SST), can observe the chromosphere in the H and K lines of Ca II at high spatial and spectral resolution. Accurate modeling as well as an understanding of the formation…

The magnetic field of the quiet-Sun chromosphere remains a mystery for solar physicists. The reduced number of chromospheric lines are intrinsically hard to model and only a few of them are magnetically sensitive. In this work, we use a 3D…

Solar and Stellar Astrophysics · Physics 2012-03-22 J. de la Cruz Rodríguez , H. Socas-Navarro , M. Carlsson , J. Leenaarts

Our knowledge of the lower solar atmosphere is mainly obtained from spectropolarimetric observations, which are often carried out in the red or infrared spectral range and almost always cover only a single or a few spectral lines. Here we…

Instrumentation and Methods for Astrophysics · Physics 2019-01-30 T. L. Riethmüller , S. K. Solanki

{It is necessary to understand the dynamics of the atomic gas to use complex modeling and to carry out detailed comparisons between theoretical models and observations.}{In a companion paper, we present high resolution bidimensional…

Astrophysics · Physics 2007-05-23 P. Hennebelle , E. Audit , M. -A Miville-Deschenes

Chromospheric plages are distributed between mid-latitude and the Equator and never close to the Poles. Therefore, we suspect that the inclination angle of the solar rotation axis has an impact on the observable chromospheric emission. We…

Solar and Stellar Astrophysics · Physics 2024-10-16 G. Vanden Broeck , S. Bechet , G. Rauw , F. Clette

We consider the propagation of several entangled photons through an elastically scattering medium and study statistical properties of their speckle patterns. We find the spatial correlations of multiphoton speckles and their sensitivity to…

Optics · Physics 2016-07-20 Avraham Klein , Oded Agam , Boris Spivak

We present angular-resolved correlation measurements between photons after propagation through a three-dimensional disordered medium. The multiple scattering process induces photon correlations that are directly measured for light sources…

Optics · Physics 2011-06-30 Stephan Smolka , Otto L. Muskens , Ad Lagendijk , Peter Lodahl

Observing the excitation mechanisms of incompressible transverse waves is vital for determining how energy propagates through the lower solar atmosphere. We aim to show the connection between convectively driven photospheric flows and…

Solar and Stellar Astrophysics · Physics 2015-06-15 R. J. Morton , G. Verth , V. Fedun , S. Shelyag , R. Erdélyi

We model the deepest observable layers of dark sunspot umbral atmospheres in terms of an empirical model which equally describes observed near infrared continuum intensities and line profiles. We use the umbral continuum intensity at 1.67…

Solar and Stellar Astrophysics · Physics 2012-10-17 Goetz Stellmacher , Eberhard Wiehr

Propagating slow waves in coronal loops exhibit a damping which depends upon the frequency of the waves. In this study we aim to investigate the relationship of the damping length (L$_d$) with the frequency of the propagating wave. We…

Solar and Stellar Astrophysics · Physics 2016-03-23 Sudip Mandal , Norbert Magyar , Ding Yuan , Tom Van Doorsselaere , Dipankar Banerjee

A rich spectrum of molecular hydrogen (H$_2$) emission lines is seen in sensitive observations from the far ultraviolet (FUV) channels of the Interface Region Imaging Spectrograph (IRIS) during flare activity in solar active region NOAA…

Solar and Stellar Astrophysics · Physics 2024-10-08 Sarah A. Jaeggli , Adrian N. Daw
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