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Related papers: The Solar X-ray Limb

200 papers

Observations of solar flares with RHESSI have shown X-ray sources traveling along flaring loops, from the corona down to the chromosphere and back up. The 28 November 2002 C1.1 flare, first observed with RHESSI by Sui et al. 2006 and…

Solar and Stellar Astrophysics · Physics 2016-02-17 Jeffrey W. Reep , Stephen J. Bradshaw , Gordon D. Holman

Flare ribbons are bright manifestations of flare energy dissipation in the lower solar atmosphere. For the first time, we report on high-resolution imaging spectroscopy observations of flare ribbons situated off-limb in the H$\beta$ and Ca…

Solar and Stellar Astrophysics · Physics 2020-07-01 D. Kuridze , M. Mathioudakis , P. Heinzel , J. Koza , H. Morgan , R. Oliver , A. F. Kowalski , J. C. Allred

We analyse the observational characteristics for a set of Long Duration Events (LDE) using Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Excellent energy resolution (1 keV) of HXR images reconstructed with RHESSI allowed us…

Solar and Stellar Astrophysics · Physics 2015-03-19 Tomasz Mrozek , Zbigniew Koltun , Sylwester Kolomanski , Urszula Bak-Steslicka

The detailed knowledge of plasma heating and acceleration region properties presents a major observational challenge in solar flare physics. Using the Ramaty High Energy Solar Spectroscopic Imager (RHESSI), the high temperature differential…

Solar and Stellar Astrophysics · Physics 2015-12-02 Natasha Jeffrey , Eduard Kontar , Brian Dennis

The preflare phase of the flare SOL2011-08-09T03:52 is unique in its long duration, its coverage by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Nobeyama Radioheliograph, and the presence of three well-developed…

Solar and Stellar Astrophysics · Physics 2017-10-18 A. O. Benz , M. Battaglia , M. Guedel

For the first time, we have used RHESSI's spatial and energy resolution to determine the combined chromospheric and coronal density profile of the flaring solar atmosphere in a statistical manner, using a dataset of 838 flares observable in…

Solar and Stellar Astrophysics · Physics 2015-06-03 Pascal Saint-Hilaire , Sam Krucker , Robert P. Lin

The hard X-ray (HXR) emission in solar flares comes almost exclusively from a very small part of the flaring region, the footpoints of magnetic loops. Using RHESSI observations of solar flare footpoints, we determine the radial positions…

Solar and Stellar Astrophysics · Physics 2015-05-27 Marina Battaglia , Eduard P. Kontar

Context: Hard X-rays from solar flares are an important diagnostic of particle acceleration and transport in the solar atmosphere. Any observed X-ray flux from on-disc sources is composed of direct emission plus Compton backscattered…

Solar and Stellar Astrophysics · Physics 2015-05-20 Marina Battaglia , Eduard P. Kontar , Iain G. Hannah

We present the first in-depth statistical survey of flare source heights observed by RHESSI. Flares were found using a flare-finding algorithm designed to search the 6-10 keV count-rate when RHESSI's full sensitivity was available in order…

Solar and Stellar Astrophysics · Physics 2015-05-27 Steven Christe , S Krucker , Pascal Saint-Hilaire

Spectroscopic observations of solar flares provide critical diagnostics of the physical conditions in the flaring atmosphere. Some key features in observed spectra have not yet been accounted for in existing flare models. Here we report a…

Solar and Stellar Astrophysics · Physics 2016-08-16 Fatima Rubio da Costa , Lucia Kleint , Vahé Petrosian , Wei Liu , Joel C. Allred

One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new Compressed Sensing-based algorithm named VIS_CS, which reconstructs the spatial distribution…

Solar and Stellar Astrophysics · Physics 2017-11-01 Simon Felix , Roman Bolzern , Marina Battaglia

The Reuven Ramaty High Energy Spectroscopic Solar Imager (RHESSI) uses the rotational modulation principle to observe temporally, spatially, and spectrally resolved hard X ray and gamma ray images of solar flares. In order to track the…

Astrophysics · Physics 2009-11-10 Kaspar Arzner

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

Fermi-LAT >30 MeV observations have increased the number of detected solar flares by almost a factor of 10 with respect to previous space observations. These sample both the impulsive and long duration phases of GOES M and X class flares.…

Solar and Stellar Astrophysics · Physics 2019-08-14 Melissa Pesce-Rollins , Nicola Omodei , Vahe' Petrosian , Wei Liu , Fatima Rubio da Costa , Alice Allafort

We have performed the first polarimetry of solar flare emission at gamma-ray energies (0.2-1 MeV). These observations were performed with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) for two large flares: the GOES…

Astrophysics · Physics 2009-11-13 Steven E. Boggs , W. Coburn , E. Kalemci

X-ray and EUV observations are an important diagnostic of various plasma parameters of the solar atmosphere during solar flares. Soft X-ray and EUV observations often show coronal sources near the top of flaring loops, while hard X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Marina Battaglia , Eduard P. Kontar

The bulk of solar flare emission originates from very compact sources located in the lower solar atmosphere and seen in various wavelength ranges: near optical, UV, EUV, soft and hard X-rays, and gamma-ray emission, yet very few spatially…

Solar and Stellar Astrophysics · Physics 2015-05-28 Marina Battaglia , Eduard P. Kontar

The aim of the present work is to specify the spatio-temporal characteristics of flare activity observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and Geostationary Operational Environmental Satellite (GOES)…

Solar and Stellar Astrophysics · Physics 2016-10-21 N. Gyenge , A. Ludmány , T. Baranyi

This paper describes the X-ray and gamma-ray imaging spectroscopy capabilities of the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). It also outlines RHESSI's major scientific accomplishments during the 16 years of operations from…

Solar and Stellar Astrophysics · Physics 2023-04-05 Brian R. Dennis , Albert Y. Shih , Gordon J. Hurford , Pascal Saint-Hilaire

Regularized imaging spectroscopy was introduced for the construction of electron flux images at different energies from count visibilities recorded by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). In this work we seek…

Solar and Stellar Astrophysics · Physics 2023-11-14 Anna Volpara , Paolo Massa , Sam Krucker , A Gordon Emslie , Michele Piana , Anna Maria Massone