English
Related papers

Related papers: Estimating the coronal supra-arcade downflows radi…

200 papers

Solar flares observed in the 200-400 GHz radio domain may exhibit a slowly varying and time-extended component which follows a short (few minutes) impulsive phase and which lasts for a few tens of minutes to more than one hour. The few…

Solar and Stellar Astrophysics · Physics 2011-11-21 G. Trottet , J. -P. Raulin , G. Giménez de Castro , T. Lüthi , A. Caspi , C. H. Mandrini , M. L. Luoni , P. Kaufmann

A number of recent lines of evidence point towards the presence of hot, out-flowing plasma from the central regions of compact Galactic and extragalactic X-ray sources. Additionally, it has long been noted that many of these sources exhibit…

Astrophysics · Physics 2009-11-10 Lev Titarchuk , Chris Shrader

Quasi-periodic disturbances have been observed in the outer solar atmosphere for many years now. Although first interpreted as upflows (Schrijver et al. (1999)), they have been widely regarded as slow magnetoacoustic waves, due to observed…

Solar and Stellar Astrophysics · Physics 2015-06-05 G. Kiddie , I. De Moortel , G. Del Zanna , S. W. McIntosh , I. Whittaker

We use the Expanded Very Large Array to image radio continuum emission from local luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) in 1 GHz windows centered at 4.7, 7.2, 29, and 36 GHz. This allows us to probe the integrated…

M-dwarf flare stars like AD Leo are laboratories for studying intense magnetic activities. The coherent radio bursts they produce are powerful probes of stellar coronal plasma and magnetic fields. In this study, we present high-resolution…

Solar and Stellar Astrophysics · Physics 2026-04-02 Wenjie Zou , Hui Tian , Jiale Zhang , Yuhang Gao

Active Galactic Nuclei (AGN) host accreting supermassive black holes (SMBHs). The accretion can lead to the formation of a hot, X-ray emitting corona close to the SMBH capable of accelerating relativistic electrons. Observations in the…

We observed several nearby face-on spiral galaxies with the ROSAT PSPC to study their 0.1-2.0 keV diffuse emission. After the exclusion of resolved discrete sources, there is unresolved X-ray emission in all the galaxies observed. Since…

Astrophysics · Physics 2009-10-28 Wei Cui , Wilton T. Sanders , Dan McCammon , Steven L. Snowden , Donna S. Womble

The substellar triple system VHS J125601.92$-$125723.9 is composed by an equal-mass M7.5 brown dwarf binary and a L7 low-mass substellar object. In this work, we aim to identify the origin of the radio emission occurring in the central…

The aim of this work is to study the energy transport by means of MHD waves propagating in quiet Sun magnetic topology from layers below the surface to the corona. Upward propagating waves find obstacles, such as the equipartition layer…

Solar and Stellar Astrophysics · Physics 2015-05-13 Irantzu C. Santamaria , Elena Khomenko , Manuel Collados

We present a study of diffuse extragalactic radio emission at $1.75\,$GHz from part of the ELAIS-S1 field using the Australia Telescope Compact Array. The resulting mosaic is $2.46\,$deg$^2$, with a roughly constant noise region of…

Astrophysics of Galaxies · Physics 2015-06-22 T. Vernstrom , Ray P. Norris , Douglas Scott , J. V. Wall

Understanding the solar corona requires knowledge of its dynamics through its various layers and subsequent connectivity to the heliosphere. This requires understanding the nature of the outflows and the physical transitions through the…

Solar and Stellar Astrophysics · Physics 2023-03-29 Nathalia Alzate , Huw Morgan , Simone Di Matteo

To explain the broad-band spectral energy distributions (SED) of Seyfert nuclei and QSOs, we study the emission spectrum emerging from a vertical disk-corona structure composed of a two-temperature plasma by solving hydrostatic equilibrium…

Astrophysics · Physics 2009-10-31 T. Kawaguchi , T. Shimura , S. Mineshige

Slow magnetoacoustic waves in a static background provide a seismological tool to probe the solar atmosphere in the analytic frame. By analyzing the spatiotemporal variation of the electron number density of plume structure in coronal holes…

Solar and Stellar Astrophysics · Physics 2020-09-09 Il-Hyun Cho , Valery M. Nakariakov , Yong-Jae Moon , Jin-Yi Lee , Dae Jung Yu , Kyung-Suk Cho , Vasyl Yurchyshyn , Harim Lee

We have shown previously that SOHO/UVCS data allow us to detect active region (AR) outflows at coronal altitudes higher than those reached by other instrumentation. These outflows are thought to be a component of the slow solar wind. Our…

Solar and Stellar Astrophysics · Physics 2016-10-07 L. Zangrilli , G. Poletto

Deep combination radio observations at 1.4GHz with the VLA and MERLIN have imaged a region 10 arcminutes square surrounding the Hubble Deep Field North (HDF-N). Initial studies of the weak radio source population have shown that the…

Astrophysics · Physics 2007-05-23 T. W. B. Muxlow , R. J. Beswick , H. Thrall , A. M. S Richards , S. T. Garrington , A. Pedlar

PDS 70c is a source of Ha emission and variable sub-mm signal. Understanding its emission mechanisms may enable observations of accretion rates and physical conditions in the circum-planetary environment. We report ALMA observations of PDS…

The analysis of multiwavelength properties of propagating disturbances (PDs) using Hinode/EIS observations is presented. Quasi-periodic PDs were mostly interpreted as slow magnetoacoustic waves in early studies, but recently suggested to be…

Solar and Stellar Astrophysics · Physics 2015-01-19 Tongjiang Wang , Leon Ofman , Joseph M. Davila

Quasi-periodic propagating intensity disturbances (PDs) have been observed in large coronal loops in EUV images over a decade, and are widely accepted to be slow magnetosonic waves. However, spectroscopic observations from Hinode/EIS…

Solar and Stellar Astrophysics · Physics 2014-04-24 Tongjiang Wang , Leon Ofman , Joseph M. Davila

Two families of models are currently considered to describe an accretion flow onto black holes and production of the observed X-ray radiation: (1) a standard cold accretion disk with a hot corona above it and (2) an outer truncated…

Astrophysics · Physics 2009-11-10 M. A. Sobolewska , A. Siemiginowska , P. T. Zycki

We present 16 GHz (1.9 cm) deep radio continuum observations made with the Arcminute Microkelvin Imager (AMI) of a sample of low-mass young stars driving jets. We combine these new data with archival information from an extensive literature…