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Related papers: Cloud Modeling of a Network Region in H-alpha

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A number of recent investigations have revealed that transverse waves are ubiquitous in the solar chromosphere. The vast majority of these have been reported in limb spicules and active region fibrils. We investigate long-lived, quiet Sun,…

Solar and Stellar Astrophysics · Physics 2015-06-04 D. Kuridze , R. J. Morton , R. Erdélyi , G. D. Dorrian , M. Mathioudakis , D. B. Jess , F. P. Keenan

Below the scale of supergranules we find that cellular flows are present in the solar photosphere at two distinct size scales, approximately 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a…

Astrophysics · Physics 2015-06-24 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin

To interpret H_2 quasar absorption line observations in Damped Ly-alpha clouds (DLAs), we model the H_2 spatial distribution within a DLA. Based on numerical simulations of disk structures with parameters similar to those derived for such…

Astrophysics · Physics 2009-11-07 H. Hirashita , A. Ferrara , K. Wada , P. Richter

Measurements of the vertical velocity of ice crystals using a 1.5micron Doppler lidar are described. The statistics from a continuous sample of stratiform ice clouds over 17 months are analysed: the distribution of velocity varies strongly…

Atmospheric and Oceanic Physics · Physics 2015-05-13 C. D. Westbrook , A. J. Illingworth

A new molecular hydrogen cloud is found in the sub-damped Ly-alpha absorber [log N(HI)=19.88+/-0.05] at the redshift z=1.15 toward the bright quasar HE0515-4414 (zem = 1.71). More than 30 absorption features in the Lyman band system of H2…

Astrophysics · Physics 2009-11-10 D. Reimers , R. Baade , R. Quast , S. A. Levshakov

Chromospheric wave activity around flares and filaments has been a research focus for years, and could provide indirect measurements of local conditions that are not otherwise accessible. One interesting observed phenomenon is oscillations…

Solar and Stellar Astrophysics · Physics 2013-02-14 J. Jackiewicz , K. S. Balasubramaniam

We present an extensive comparison of models of structure formation with observations, based on linear and quasi-linear theory. We assume a critical matter density, and study both cold dark matter models and cold plus hot dark matter…

Astrophysics · Physics 2015-06-24 Andrew R Liddle , David H Lyth , R K Schaefer , Q Shafi , Pedro T P Viana

We present an analysis of cosmological models with mixed dark matter (spectrum slope of density perturbations $n_S \in [0.6, 1.6]$, hot dark matter abundance $\Omega_\nu \in [0.0, 0.6]$) in spatially flat Universe, based on Press-Schechter…

Astrophysics · Physics 2011-04-15 N. A. Arkhipova , V. N. Lukash , E. V. Mikheeva

Cold atomic clouds are promising platforms for generating correlated photons, but multiple scattering and associated Doppler broadening limit their temporal coherence. Here we demonstrate that cloud geometry provides a powerful means to…

We compare the properties of clouds in simulated M33 galaxies to those observed in the real M33. We apply a friends of friends algorithm and CPROPS to identify clouds, as well as a pixel by pixel analysis. We obtain very good agreement…

Astrophysics of Galaxies · Physics 2019-03-20 C. L. Dobbs , E. Rosolowsky , A. R. Pettitt , J. Braine , E. Corbelli , J. Sun

Solar light gets scattered at cloud top level in Venus' atmosphere, in the visible range, which corresponds to the altitude of 67 km. We present Doppler velocity measurements performed with the high resolution spectrometer MTR of the Solar…

Earth and Planetary Astrophysics · Physics 2010-11-12 P. Gaulme , F. -X Schmider , C. Grec , A. Lopez Ariste , T. Widemann , B. Gelly

It is widely assumed that dust opacities in molecular clouds follow a power-law profile with an index, $\beta$. Recent studies of the Orion Molecular Cloud (OMC) 2/3 complex, however, show a flattening in the spectral energy distribution…

We investigate cooperative fluorescence in a dilute cloud of strongly driven two-level emitters. Starting from the Heisenberg equations of motion, we compute the first-order scattering corrections to the saturation of the excited-state…

Atomic Physics · Physics 2013-06-06 J. R. Ott , M. Wubs , P. Lodahl , N. A. Mortensen , R. Kaiser

Only a handful of late-T brown dwarfs have been monitored for spectro-photometric variability, leaving incomplete the study of the atmospheric cloud structures of the coldest brown dwarfs, that share temperatures with some cold,…

Solar and Stellar Astrophysics · Physics 2022-07-27 Elena Manjavacas , Theodora Karalidi , Xianyu Tan , Johanna M. Vos , Ben W. P. Lew , Beth A. Biller , Natalia Oliveros-Gomez

We perform three-dimensional (3D) compressible MHD simulations over many dynamical times for an extended range of sonic and Alfven Mach numbers and analyze the statistics of 3D density and 2D column density, which include probability…

Astrophysics · Physics 2009-01-19 G. Kowal , A. Lazarian , A. Beresnyak

Standing slow mode waves in hot flaring loops are exclusively observed in spectrometers and are used to diagnose the magnetic field strength and temperature of the loop structure. Due to the lack of spatial information, the longitudinal…

Solar and Stellar Astrophysics · Physics 2015-07-15 D. Yuan , T. Van Doorsselaere , D. Banerjee , P. Antolin

The transition from the diffuse warm neutral medium (WNM) to the dense cold neutral medium (CNM) is what set the initial conditions to the formation of molecular clouds. The properties of the turbulent cascade in the WNM, essential to…

Astrophysics of Galaxies · Physics 2021-03-03 Antoine Marchal , Marc-Antoine Miville-Deschênes

The massive dark matter halos that host groups and clusters of galaxies have observable properties that appear to be log-normally distributed about power-law mean scaling relations in halo mass. Coupling this assumption with either…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 August E. Evrard , Pablo Arnault , Dragan Huterer , Arya Farahi

We study the observable signatures of self-gravitating MHD turbulence by applying the probability density functions (PDFs) and the spatial density power spectrum to synthetic column density maps. We find that there exists three…

Solar and Stellar Astrophysics · Physics 2015-08-06 Blakesley Burkhart , David C. Collins , Alex Lazarian

Analysis of all-sky Planck submillimetre observations and the IRAS 100um data has led to the detection of a population of Galactic cold clumps. The clumps can be used to study star formation and dust properties in a wide range of Galactic…

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