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Related papers: Coronal activity with XMM-Newton and Chandra

200 papers

Two sources of X-ray emission are expected from planetary nebulae: the hot central stars with $T_{eff} > 10^5$ K, and shocked fast stellar winds at temperatures of 10$^6 - 10^7$ K. The stellar emission and nebular emission differ in spatial…

Astrophysics · Physics 2007-05-23 You-Hua Chu , Martin A. Guerrero , Robert A. Gruendl

Magnetic fields in the sun's outer atmosphere -- the corona -- control both solar-wind acceleration and the dynamics of solar eruptions. We present the first clear observational evidence of coronal magnetic nulls in off-limb linearly…

We present a survey of X-ray emission from young stars in the Sword of Orion star-formation region using XMM-Newton's EPIC detectors. We find over 850 X-ray sources, of which more than 700 have near-infrared counterparts consistent with…

Astrophysics · Physics 2007-05-23 K. R. Briggs , M. Guedel , M. Audard , K. W. Smith

Recent discoveries have revealed exoplanets orbiting young Sun-like stars, offering a window into the early solar system. These young stars frequently produce extreme magnetic explosions known as superflares, roughly once a day, potentially…

Solar and Stellar Astrophysics · Physics 2025-10-28 Kosuke Namekata

The advent of moderately high-resolution X-ray spectroscopy with Chandra and XMM promised to usher in a new age in the study of neutron stars: we thought we would study neutron stars like stars, with resolved absorption spectra revealing…

During the last few years our knowledge about the X-ray emission from bodies within the solar system has significantly improved. Several new solar system objects are now known to shine in X-rays at energies below 2 keV. Apart from the Sun,…

The properties of the population of compact objects created in core-collapse supernovae (SNe) are uncertain. X-ray observations years to decades after the explosions offer a way to gain insight into this, as hard X-ray emission from the…

High Energy Astrophysical Phenomena · Physics 2025-11-06 Julia Ahlvind , Josefin Larsson , Dennis Alp

We continue the investigation of a CME-driven coronal dimming from December 14 2006 using unique high resolution imaging of the chromosphere and corona from the Hinode spacecraft. Over the course of the dimming event we observe the dynamic…

Solar and Stellar Astrophysics · Physics 2009-01-20 Scott W. McIntosh , Joan Burkepile , Robert J. Leamon

The possibility for direct investigation of thermal emission from isolated neutron stars was opened about 25 years ago with the launch of the first X-ray observatory, Einstein. A significant contribution to this study was provided by ROSAT…

Astrophysics · Physics 2009-01-12 Vyacheslav E. Zavlin

Observations of strong solar wind proton flux correlations with ROSAT X-ray rates along with high spectral resolution Chandra observations of X-rays from the dark Moon show that soft X-ray emission mirrors the behavior of the solar wind. In…

Astrophysics · Physics 2009-11-10 M. R. Collier , T. E. Moore , S. L. Snowden , K. D. Kuntz

It has been known for over 30 years that Galactic globular clusters (GCs) are overabundant by orders of magnitude in bright X-ray sources per unit mass relative to the disk population. Recently a quantitative understanding of this…

Astrophysics · Physics 2009-11-13 John M. Fregeau

We present highlights from a study of a sample of 10 extreme-luminosity candidate ultraluminous X-ray sources (L_X > 5 x 10^(40) erg sec^(-1)), all at distances < 100 Mpc, identified from a cross-correlation of the RC3 catalogue of galaxies…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Andrew D. Sutton , Timothy P. Roberts , Dominic J. Walton

Stellar activity can be observed at different wavelengths in a variety of different activity indicators. We investigated the correlation between coronal and chromospheric emissions by combining X-ray data from stars detected in the eROSITA…

Solar and Stellar Astrophysics · Physics 2025-04-25 S. Freund , S. Czesla , B. Fuhrmeister , P. Predehl , J. Robrade , P. C. Schneider , J. H. M. M. Schmitt

We present lightcurves obtained in X-ray by the XMM-Newton EPIC cameras and simultaneous radio lightcurves obtained with the VLA for five active M-type flare stars. A number of flare events were observed, and by comparing radio with X-ray…

Astrophysics · Physics 2009-11-10 K. W. Smith , M. Guedel , M. Audard

In these lecture notes I briefly discuss the present day situation and new discoveries in astrophysics of neutron stars focusing on isolated objects. The latter include soft gamma repeaters, anomalous X-ray pulsars, central compact objects…

Astrophysics · Physics 2007-05-23 S. B. Popov

A personal selection of noteworthy X-ray results on CVs are presented, with emphasis on XMM-Newton and Chandra observations. Progressing roughly from broad-band view to narrow-band, high spectral resolution studies, I summarize: the energy…

Astrophysics · Physics 2007-05-23 K. Mukai

Active galactic nuclei (AGN) are extremely variable in the X-ray band down to very short timescales. However, the driver behind the X-ray variability is still poorly understood. Previous results suggest that the hot corona responsible for…

The X-ray Multi-Mirror Mission XMM-Newton is ESA's largest observatory so far; it is dedicated to explore the Universe in the 0.2 - 15 keV X-ray band of the electromagnetic spectrum. Because of its large collecting area very faint sources…

Astrophysics · Physics 2007-05-23 W. Becker , B. Aschenbach

We highlight recent theoretical and observational progress in several areas of neutron star astrophysics, and discuss the prospect for advances in the next decade.

Magnetic activity is a ubiquitous feature of stars with convective outer layers, with implications from stellar evolution to planetary atmospheres. Investigating the mechanisms responsible for the observed stellar activity signals from days…

Solar and Stellar Astrophysics · Physics 2023-10-17 Emre Işık , Jennifer L. van Saders , Ansgar Reiners , Travis S. Metcalfe