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Related papers: A Model for the Origin of High Density in Loop-top…

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Solar flare hard X-rays (HXRs) are produced as bremsstrahlung when an accelerated population of electrons interacts with the dense chromospheric plasma. HXR observations presented by using the Ramaty High-Energy Solar Spectroscopic Imager…

Solar and Stellar Astrophysics · Physics 2014-11-20 A. O'Flannagain , J. C. Brown , P. T. Gallagher

Magnetic reconnection is invoked as an efficient particle accelerator in a variety of astrophysical sources of non-thermal high-energy radiation. With large-scale two-dimensional particle-in-cell simulations of relativistic reconnection…

High Energy Astrophysical Phenomena · Physics 2018-10-17 Maria Petropoulou , Lorenzo Sironi

Unraveling and controlling chemical dynamics requires techniques to image structural changes of molecules with femtosecond temporal and picometer spatial resolution. Ultrashort-pulse x-ray free-electron lasers have significantly advanced…

We examine a systematic comparison of jet-knots, hotspots and radio lobes recently observed with Chandra and ASCA. This report will discuss the origin of their X-ray emissions and investigate the dynamics of the jets. The data was compiled…

Astrophysics · Physics 2009-11-10 Jun Kataoka , Lukasz Stawarz

Magnetic reconnection is a well-accepted part of the theory of solar eruptive events, though the evidence is still circumstantial. Intrinsic to the reconnection picture of a solar eruptive event, particularly in the standard model for…

Solar and Stellar Astrophysics · Physics 2017-09-20 Juntao Wang , P. J. A. Simoes , N. L. S. Jeffrey , L. Fletcher , P. J. Wright , I. G. Hannah

We present data analysis and interpretation of an M1.4-class flare observed with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) on April 30, 2002. This event, with its footpoints occulted by the solar limb, exhibits a…

Astrophysics · Physics 2009-03-04 Wei Liu , Vahe' Petrosian , Brian R. Dennis , Yan Wei Jiang

During eruptive flares, vector magnetograms show increasing horizontal magnetic field and downward Lorentz force in the Sun's photosphere around the polarity-inversion line. Such behavior has often been associated with the implosion…

Solar and Stellar Astrophysics · Physics 2019-06-05 Krzysztof Barczynski , Guillaume Aulanier , Sophie Masson , Michael S. Wheatland

Using the HEAO1 A2 full sky, 2-10 keV X-ray map evidence is found for the presence of diffuse X-ray emission in the plane of the local supercluster. Fitting this diffuse component with a simple ``pillbox'' model implies a volume X-ray…

Astrophysics · Physics 2007-05-23 Stephen P. Boughn

Utilizing low-luminosity star-forming systems discovered in the H$\alpha$ Dots survey, we present spectroscopic observations undertaken using the KPNO 4m telescope for twenty-six sources. With determinations of robust, "direct"-method metal…

Astrophysics of Galaxies · Physics 2022-02-09 Alec S. Hirschauer , John J. Salzer , Nathalie Haurberg , Caryl Gronwall , Steven Janowiecki

Kinetic Riemann simulations have been completed to explore particle heating during guide field reconnection in the low-$\beta$ environment of the inner heliosphere and the solar corona. The reconnection exhaust is bounded by two rotational…

Plasma Physics · Physics 2019-09-04 Qile Zhang , J. F. Drake , M. Swisdak

We use deep follow-up XMM-Newton observations of 6 clusters discovered in the XXL Survey at $z>1$ to gain robust measurements of their X-ray properties and to investigate the extent to which scaling relations at low redshift are valid at…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-11 R. T. Duffy , C. H. A. Logan , B. J. Maughan , D. Eckert , N. Clerc , S. Ettori , F. Gastaldello , E. Koulouridis , M. Pierre , M. Ricci , M. Sereno , I. Valtchanov , J. P. Willis

We have developed an improved model of X-ray emission from optically thin, two-temperature accretion flows, \texttt{kerrflow}, using an exact Monte Carlo treatment of global Comptonization as well as with a fully general relativistic…

High Energy Astrophysical Phenomena · Physics 2022-06-15 Andrzej Niedźwiecki , Michał Szanecki , Andrzej A. Zdziarski , Fu-Guo Xie

In the interaction of high-power laser beams with solid density plasma there are a number of mechanisms that generate strong magnetic fields. Such fields subsequently inhibit or redirect electron flows, but can themselves be advected by…

Plasma Physics · Physics 2015-08-31 A. S. Joglekar , A. G. R. Thomas , W. Fox , A. Bhattacharjee

The interaction of optically emitting clouds with warm X-ray gas and hot, tenuous radio plasma in radio jet cocoons is modelled by 2D compressible hydrodynamic simulations. The initial setup is the Kelvin-Helmholtz instability at a contact…

Astrophysics · Physics 2008-11-26 Martin Krause , Paul Alexander

Motivated by the observations of high Faraday rotation measures measured in cooling flow clusters we propose a model relevant to plasmas with comparable thermal and magnetic pressures. Magnetic field reconnection may play a major role in…

Astrophysics · Physics 2009-10-28 Colin Norman , Avery Meiksin

The high densities, long lifetimes, and narrow emission measure distributions observed in coronal loops with apex temperatures near 1 MK are difficult to reconcile with physical models of the solar atmosphere. It has been proposed that the…

Solar and Stellar Astrophysics · Physics 2010-04-08 Harry P. Warren , David M. Kim , Amanda M. DeGiorgi , Ignacio Ugarte-Urra

We investigate guide-field magnetic reconnection and particle acceleration in relativistic pair plasmas with three-dimensional particle-in-cell (PIC) simulations of a kinetic-scale current sheet in a periodic geometry at low magnetizations.…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Daniel Kagan , Milos Milosavljevic , Anatoly Spitkovsky

Relativistic magnetic reconnection is a powerful agent through which magnetic energy can be tapped in astrophysics, energizing particles that then produce observed radiation. In some systems, the highest energy photons come from particles…

High Energy Astrophysical Phenomena · Physics 2021-10-04 J. M. Mehlhaff , G. R. Werner , D. A. Uzdensky , M. C. Begelman

Solar flares are widely accepted to be powered by magnetic reconnection that involves complex dynamics in various scales. The flare supra-arcade and loop-top region, directly impacted by fast reconnection downflows, contains a wealth of…

Solar and Stellar Astrophysics · Physics 2025-05-27 Tingyu Gou , Katharine K. Reeves

Magnetic reconnection at the interface between coronal holes and loops, so-called interchange reconnection, can release the hotter, denser plasma from magnetically confined regions into the heliosphere, contributing to the formation of the…

Solar and Stellar Astrophysics · Physics 2015-03-13 A. F. Rappazzo , W. H. Matthaeus , D. Ruffolo , S. Servidio , M. Velli