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Related papers: Morphology and evolution of umbral dots and their …

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Context. Understanding the survival and orbital evolution of brown dwarf (BD) companions during the post-main-sequence (MS) evolution of their host stars is increasingly important, especially with recent discoveries of many substellar…

Solar and Stellar Astrophysics · Physics 2026-03-19 Zhangliang Chen , Hongming Jin , Hongwei Ge , Cong Yu , Kejun Wang , Dichang Chen , Bo Ma

The galaxy Luminosity Function (LF) has been estimated in the rest frame B luminosity at 0<z<1.25 and at 1700 {\AA} for 2.5<z<4.5 from deep multicolor surveys in the HDF-N, HDF-S, NTT-DF. The results have been compared with a recent version…

Astrophysics · Physics 2009-11-06 F. Poli , N. Menci , E. Giallongo , A. Fontana , S. Cristiani , S. D' Odorico

Umbral flashes (UFs) are emissions in the core of chromospheric lines caused by upward propagating waves steepening into shocks. UFs are followed by an expanding blue shifted umbral wave (UW) and red-shifted plasma returning to the initial…

Solar and Stellar Astrophysics · Physics 2020-07-01 Vasyl Yurchyshyn , Ali Kilcik , Seray Sahin , Valentina Abramenko , Eun-Kyung Lim

Plumes have been proposed to channel MHD waves and the solar wind into the heliosphere. High-speed propagating disturbances (PDs), though well detected in plumes, cannot yet be clearly assigned to MHD waves or to mass flows. Additionally,…

Solar and Stellar Astrophysics · Physics 2026-04-08 Ziwen Huang , L. P. Chitta , L. Teriaca , R. Aznar Cuadrado , H. Peter , S. K. Solanki , T. Wiegelmann , F. Plaschke

Study on the small-scale structures and material flows of solar quiescent filaments is very important for understanding the formation and equilibrium of solar filaments. Using the high resolution H{\alpha} data observed by the New Vacuum…

Solar and Stellar Astrophysics · Physics 2015-10-14 X. L. Yan , Z. K. Xue , Y. Y. Xiang , L. H. Yang

We compare horizontal velocities, vertical magnetic fields and evolution of trees of fragmenting granules (TFG, also named families of granules) derived in the quiet Sun at disk center from observations at solar minimum and maximum of the…

Solar and Stellar Astrophysics · Physics 2018-04-11 J. M. Malherbe , T. Roudier , R. Stein , Z. Frank

The slowly positively drifting bursts (SPDBs) are rarely observed in radio emission of solar flares. To understand how the SPDBs are generated, we studied the radio observations at 600--5000 MHz together with the imaging observations made…

Solar and Stellar Astrophysics · Physics 2024-08-23 Alena Zemanová , Marian Karlický , Jana Kašparová , Jaroslav Dudík , Ján Rybák

Using N-body simulations of flat, dark energy dominated cosmologies, we show that galaxies around simulated binary systems resembling the Local Group (LG) have low peculiar velocities, in good agreement with observational data. We have…

Astrophysics · Physics 2009-11-10 Andrea V. Maccio' , Fabio Governato , Cathy Horellou

Filamentary structures are ubiquitous in the interstellar medium, yet their formation, internal structure, and longevity have not been studied in detail. We report the results from a comprehensive numerical study that investigates the…

Astrophysics of Galaxies · Physics 2015-11-18 Wladimir Banda-Barragán , Ross Parkin , Christoph Federrath , Roland Crocker , Geoffrey Bicknell

Delta ($\delta$)-spots are active regions (ARs) in which positive and negative umbrae share a penumbra. They are known to be the source of strong flares. We introduce a new quantity, the degree of $\delta$ (Do$\delta$), to measure the…

Solar and Stellar Astrophysics · Physics 2022-10-26 A. A. Norton , P. J. Levens , K. J. Knizhnik , M. G. Linton , Y. Liu

We constrain mass, lifetime and contribution of a very slowly decaying Ultra Heavy Dark Matter (UHDM) by simulating the cosmological evolution of its remnants. Most of interactions which participate in energy dissipation are included in the…

Astrophysics · Physics 2008-11-26 Houri Ziaeepour

We apply methods from Bayesian inferencing and graph theory to a dataset of 102 mid-infrared spectra, and archival data from the optical to the millimeter, to construct an evolutionary paradigm for z<0.4 infrared-luminous galaxies (ULIRGs).…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 D. Farrah , B. Connolly , N. Connolly , H. Spoon , S. Oliver , H. Prosper , L. Armus , J. R. Houck , A. R. Liddle , V. Desai

Imaging spectroscopy using the new Palomar Integral Field Spectrograph is presented for the Pa-alpha line in four ultraluminous infrared galaxies. In most cases, we are able to establish the geometry of the merger, and thus estimate the…

Astrophysics · Physics 2009-11-06 T. W. Murphy , B. T. Soifer , K. Matthews , L. Armus

(Shortened) We use N-body simulations to investigate the structure and dynamical evolution of dark matter halos in galaxy clusters. Our sample consists of nine massive halos from an EdS universe with scale free power spectrum and n = -1.…

Astrophysics · Physics 2015-06-24 Giuseppe Tormen , Francois R. Bouchet , Simon D. M. White

We investigated the vertical penumbral plasma flow on small spatial scales using data recorded by the spectropolarimeter of the solar optical telescope onboard Hinode. To this end we computed maps of apparent Doppler velocities by comparing…

Solar and Stellar Astrophysics · Physics 2015-05-14 Morten Franz , Rolf Schlichenmaier

We make a detailed investigation of the properties of Lyman-break galaxies (LBGs) in the LambdaCDM model. We present predictions for two published variants of the GALFORM semi-analytical model: the Baugh et al. (2005) model, which has star…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. G. Lacey , C. M. Baugh , C. S. Frenk , A. J. Benson , .

(abridged)We present a comprehensive characterization of the general properties (luminosity functions, mass, size, ages, etc) of optically selected compact stellar objects (knots) in a representative sample of 32 low-z (U)LIRGs. We use ACS…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Daniel Miralles-Caballero , Luis Colina , Santiago Arribas , Pierre-Alain Duc

We examine the observable properties of simulated barred galaxies including radial mass profiles, edge-on structure and kinematics, bar lengths and pattern speed evolution for detailed comparison to real systems. We have run several…

Astrophysics · Physics 2009-11-07 J. K. O'Neill , J. Dubinski

Many studies assert that dark matter (DM) subhaloes without a baryonic counterpart and with an inner cusp always survive no matter the strength of the tidal force they undergo. In this work, we perform a suite of numerical simulations…

Astrophysics of Galaxies · Physics 2025-12-24 Alejandra Aguirre-Santaella , Miguel A. Sánchez-Conde , Go Ogiya

We determine the orbits of four double degenerate systems (DDs), composed of two white dwarfs, and of two white dwarf -- M dwarf binaries. The four DDs, WD1022+050, WD1428+373, WD1824+040, and WD2032+188, show orbital periods of 1.157155(5)…