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Related papers: Cold Solar Flares I. Microwave Domain

200 papers

A multi-wavelength spatial and temporal analysis of solar high energy electrons is conducted using the August 20, 2002 flare of an unusually flat (gamma=1.8) hard X-ray spectrum. The flare is studied using RHESSI, Halpha, radio, TRACE, and…

Astrophysics · Physics 2008-11-26 J. Kasparova , M. Karlicky , E. P. Kontar , R. A. Schwartz , B. R. Dennis

We use Renewal Theory for the estimation and interpretation of the flare rate from the Geostationary Operational Environmental Satellite (GOES) soft X-ray flare catalogue. It is found, that in addition to the flare rate variability with the…

Solar and Stellar Astrophysics · Physics 2015-03-20 Andrei Gorobets , Mauro Messerotti

We study the spectral and temporal behavior of X-ray flares from the active M-dwarf EV Lac in 200 ks of exposure with the Chandra/HETGS. We derive flare parameters by fitting an empirical function which characterizes the amplitude, shape,…

High Energy Astrophysical Phenomena · Physics 2015-05-19 David P. Huenemoerder , Norbert S. Schulz , Paola Testa , Jeremy J. Drake , Rachel A. Osten , Fabio Reale

We study the decay phase of solar flares in several spectral bands using a method based on that successfully applied to white light flares observed on an M4 dwarf. We selected and processed 102 events detected in the Sun-as-a-star flux…

Solar and Stellar Astrophysics · Physics 2021-02-10 Larisa K. Kashapova , Anne-Marie Broomhall , Alena I. Larionova , Elena G. Kupriyanova , Ilya D. Motyk

The sub-THz event observed on the 4 July 2012 with the Bauman Moscow State Technical University Radio Telescope RT-7.5 at 93 and 140~GHz as well as Kislovodsk and Mets\"ahovi radio telescopes, Radio Solar Telescope Network (RSTN), GOES,…

In this paper, the cooling of 72 M- and X-class flares is examined using GOES/XRS and SDO/EVE. The observed cooling rates are quantified and the observed total cooling times are compared to the predictions of an analytical 0-D hydrodynamic…

Solar and Stellar Astrophysics · Physics 2014-01-17 Daniel F. Ryan , Phillip C. Chamberlin , Ryan O. Milligan , Peter T. Gallgher

X-radiation from energetic electrons is the prime diagnostic of flare-accelerated electrons. The observed X-ray flux (and polarization state) is fundamentally a convolution of the cross-section for the hard X-ray emission process(es) in…

Solar and stellar flares are powerful events which produce intense radiation across the electromagnetic spectrum. Multiwavelength observations are highly important for understanding the nature of flares, because different flare-related…

Solar and Stellar Astrophysics · Physics 2021-05-12 Alexey A. Kuznetsov , Dmitrii Y. Kolotkov

Flares in Sagittarius A* are produced by hot plasmas within a few Schwarzschild radii of the supermassive black hole at the Galactic center. The recent detection of a correlation between the spectral index and flux during a near infrared…

Astrophysics · Physics 2011-02-11 Jonathan M. Bittner , Siming Liu , Christopher L. Fryer , Vahe Petrosian

We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities,…

We investigate the X-ray and UV emission detected by RHESSI and TRACE in the context of a solar flare on the 16th November 2002 with the goal of better understanding the evolution of the flare. We analysed the characteristics of the X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Hamish A. S. Reid , Nicole Vilmer , Guillaume Aulanier , Etienne Pariat

Neutrinos generated during solar flares remain elusive. However, after $50$ years of discussion and search, the potential knowledge unleashed by their discovery keeps the search crucial. Neutrinos associated with solar flares provide…

Solar and Stellar Astrophysics · Physics 2020-10-12 K. Okamoto , Y. Nakano , S. Masuda , Y. Itow , M. Miyake , T. Terasawa , S. Ito , M. Nakahata

Particle acceleration is one of the most significant features that are ubiquitous among space and cosmic plasmas. It is most prominent during flares in the case of the Sun, with which huge amount of electromagnetic radiation and high-energy…

Solar and Stellar Astrophysics · Physics 2014-05-15 Noriyuki Narukage , Masumi Shimojo , Taro Sakao

Radio observations provide powerful diagnostics of energy release, particle acceleration, and transport processes in solar flares. However, despite recent progress in radio interferometric imaging spectroscopy, current instruments still…

We present X-ray imaging and spectral analysis of all microflares the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observed between March 2002 and March 2007, a total of 25,705 events. These microflares are small flares,…

Astrophysics · Physics 2008-02-28 I. G. Hannah , S. Christe , S. Krucker , G. J. Hurford , H. S. Hudson , R. P. Lin

Bursts and flares are among the distinctive observational manifestations of magnetars, isolated neutron stars endowed with an ultra-strong magnetic field ($B \approx 10^{14}$--$10^{15}$ G). It is believed that these events arise in a hot…

High Energy Astrophysical Phenomena · Physics 2017-06-21 Roberto Taverna , Roberto Turolla

Most studies of quasi-periodic pulsations in solar flares have identified characteristic periods in the 5 - 300s range. Due to observational limitations there have been few attempts to probe the < 5s period regime and understand the…

Solar and Stellar Astrophysics · Physics 2024-06-12 Andrew R. Inglis , Laura A. Hayes

Large solar flares occasionally trigger significant space-weather disturbances that affect the technological infrastructures of modern civilization, and therefore require further investigation. Although these solar flares have been…

Solar and Stellar Astrophysics · Physics 2023-10-06 Keitarou Matsumoto , Satoshi Masuda , Masumi Shimojo , Hisashi Hayakawa

We analyse the 30 October, 2004, X1.2/SF solar event that occurred in AR 10691 (N13 W18) at around 11:44 UT. Observations at 212 and 405 GHz of the Solar Submillimeter Telescope (SST), with high time resolution (5 ms), show an intense…