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Intensity mapping surveys will provide access to a coarse view of the cosmic large-scale structure in unprecedented large volumes at high redshifts. Given the large fractions of the sky that can be efficiently scanned using emission from…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 Oliver Leicht , Cora Uhlemann , Francisco Villaescusa-Navarro , Sandrine Codis , Lars Hernquist , Shy Genel

High-resolution spectra of the magnetic star HD191612 were acquired using the Chandra X-ray observatory at both maximum and minimum emission phases. We confirm the flux and hardness variations previously reported with XMM-Newton,…

Solar and Stellar Astrophysics · Physics 2020-12-09 Yael Naze , Asif ud-Doula , Svetozar A. Zhekov

(Abridged) We report results from a comprehensive study of the nearby M dwarf Proxima Centauri with the XMM-Newton satellite. We find strongly variable coronal X-ray emission, with flares ranging over a factor of 100 in peak flux. The…

Astrophysics · Physics 2009-11-10 M. Guedel , M. Audard , F. Reale , S. L. Skinner , J. L. Linsky

We demonstrate the first time-resolved X-ray resonant magnetic scattering (tr-XRMS) experiment at the N edge of Tb at 155 eV performed using a tabletop high-brightness high-harmonic generation (HHG) source. In contrast to static X-ray…

Ultraluminous X-ray sources (ULXs) are bright X-ray sources in nearby galaxies not associated with the central supermassive black hole. Their luminosities imply they are powered by either an extreme accretion rate onto a compact stellar…

The far ultraviolet (FUV) continuum flux is recognized as a very sensitive diag- nostic of the temperature structure of the Sun's lower chromosphere. Until now analysis of the available stellar FUV data has shown that solar-type stars must…

Solar and Stellar Astrophysics · Physics 2015-05-30 Jeffrey L. Linsky , Rachel Bushinsky , Tom Ayres , Juan Fontenla , Kevin France

Non-linear force-free fields are the most general case of force-free fields, but the hardest to model as well. There are numerous methods of computing such fields by extrapolating vector magnetograms from the photosphere, but very few…

Solar and Stellar Astrophysics · Physics 2021-06-29 A. Malanushenko , D. W. Longcope , D. E. McKenzie

Context: Solar flares release a large fraction of their energy into non-thermal electrons, but it is not clear where and how. Bremsstrahlung X-rays are observed from the corona and chromosphere. Aims: We aim to characterize the acceleration…

Astrophysics · Physics 2009-11-11 Marina Battaglia , Arnold O. Benz

Chromospheric evaporation refers to dynamic mass motions in flare loops as a result of rapid energy deposition in the chromosphere. These have been observed as blueshifts in X-ray and extreme-ultraviolet (EUV) spectral lines corresponding…

Solar and Stellar Astrophysics · Physics 2015-09-23 Y. Li , M. D. Ding , J. Qiu , J. X. Cheng

We analyse the spatial distribution and vertical stratification of the physical parameters of the solar atmosphere when an X-class flare occurs. We made use of observations acquired by the Interferometric Bidimensional Spectropolarimeter…

Solar and Stellar Astrophysics · Physics 2024-06-19 F. Ferrente , C. Quintero Noda , F. Zuccarello , S. L. Guglielmino

We present detailed 3D modeling of a dense, coronal thick target X-ray flare using the GX Simulator tool, photospheric magnetic measurements, and microwave imaging and spectroscopy data. The developed model offers a remarkable agreement…

Solar and Stellar Astrophysics · Physics 2016-01-13 Gregory D. Fleishman , Yan Xu , Gelu N. Nita , Dale E. Gary

The main goal of this analysis is to present a new method to estimate the physical properties of diffuse cloud of atomic hydrogen observed at high Galactic latitude. This method, based on a comparison of the observations with fractional…

Astrophysics · Physics 2009-11-13 Marc-Antoine Miville-Deschenes , Peter G. Martin

The characteristic electron densities, temperatures, and thermal distributions of 1MK active region loops are now fairly well established, but their coronal magnetic field strengths remain undetermined. Here we present measurements from a…

Solar and Stellar Astrophysics · Physics 2021-07-14 David H. Brooks , Harry P. Warren , Enrico Landi

Some galaxy clusters show diffuse radio emission in the form of giant halos (GHs) on Mpc scales or minihalos (MHs) on smaller scales. Comparing VLA and XMM radial profiles of several such clusters, we find a universal linear correlation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Uri Keshet , Abraham Loeb

The study of galaxy cluster outskirts has emerged as one of the new frontiers in extragalactic astrophysics and cosmology with the advent of new observations in X-ray and microwave. However, the thermodynamic properties and chemical…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-24 Camille Avestruz , Erwin T. Lau , Daisuke Nagai , Alexey Vikhlinin

Spatial information from stellar X-ray coronae can be inferred by use of scaling laws from the solar corona. This requires measurement of the physical parameters temperature and density. We concentrate on the newly available density…

Astrophysics · Physics 2009-11-10 J. -U. Ness , M. Güdel , J. H. M. M. Schmitt , M. Audard , A. Telleschi

Properties of high redshift clusters are a fundamental source of information for cosmology. It has been shown by Oukbir and Blanchard (1997) that the combined knowledge of the redshift distribution of X-ray clusters of galaxies and the…

Astrophysics · Physics 2011-05-23 R. Sadat , A. Blanchard , J. Oukbir

We compare photospheric line-of-sight magnetograms from the Synoptic Long-term Investigations of the Sun (SOLIS) vector spectromagnetograph (VSM) instrument with observations from the 150-foot Solar Tower at Mt. Wilson (MWO), Helioseismic…

Solar and Stellar Astrophysics · Physics 2012-10-01 A. Pietarila , L. Bertello , J. W. Harvey , A. A. Pevtsov

We apply a new method to determine the magnetic field in coronal loops using observations of coronal loop oscillations. We analyze seven Doppler shift oscillation events detected by SUMER in the hot flare line Fe XIX to obtain oscillation…

Astrophysics · Physics 2008-11-26 Tongjiang Wang , Davina E. Innes , Jiong Qiu

Abridged. We observed the 40 Myr old star DS Tuc A with XMM-Newton and recorded two X-ray bright flares, with the second event occurring about 12 ks after the first one. Their duration from the rise to the end of the decay was of about 8-10…

Solar and Stellar Astrophysics · Physics 2022-10-26 I. Pillitteri , C. Argiroffi , A. Maggio , G. Micela , S. Benatti , F. Reale , S. Colombo , S. J. Wolk