中文
相关论文

相关论文: Is there a hard tail in the Coma Cluster X-ray spe…

200 篇论文

After the positive detection by BeppoSAX of hard X-ray radiation up to ~80 keV in the Coma cluster spectrum, we present evidence for nonthermal emission from A2256 in excess of thermal emission at a 4.6sigma confidence level. In addition to…

天体物理学 · 物理学 2009-10-31 R. Fusco-Femiano , D. Dal Fiume , S. De Grandi , L. Feretti , G. Giovannini , P. Grandi , A. Malizia , G. Matt , S. Molendi

Hard X-ray radiation has been detected for the first time in the Coma cluster by BeppoSAX. Thanks to the unprecedented sensitivity of the Phoswich Detection System (PDS) instrument, the source has been detected up to ~80 keV. There is clear…

天体物理学 · 物理学 2009-10-31 R. Fusco-Femiano , D. Dal Fiume , L. Feretti , G. Giovannini , P. Grandi , G. Matt , S. Molendi , A. Santangelo

We present first results of the BeppoSAX observation of the Coma Cluster. Thanks to the unprecedented sensitivity of the PDS instrument, the source has been detected up to ~80 keV. There is clear evidence for emission in excess to the…

天体物理学 · 物理学 2007-05-23 R. Fusco-Femiano , D. Dal Fiume , L. Feretti , G. Giovannini , G. Matt , S. Molendi

The Coma cluster of galaxies hosts the brightest radio halo known and has therefore been the target of numerous searches for associated inverse Compton (IC) emission, particularly at hard X-ray energies where the IC signal must eventually…

We report the hard X-ray spectrum of the Coma cluster obtained using the PDS data of two independent BeppoSAX observations performed with a time interval of about three years. In both the spectra a non thermal excess with respect to the…

In this note, we reply to Fusco-Femiano et al. (2004) and Fusco-Femiano et al. (2006), who cast doubts on our analysis of the PDS observations of the Coma Cluster which we describe in Rossetti & Molendi (2004). We discuss the main issues in…

天体物理学 · 物理学 2007-05-23 M. Rossetti , S. Molendi

We present results of X-ray observations of the Coma cluster with multiple instruments over a broad energy band. Using the data from INTEGRAL, RXTE and ROSAT observatories, we find that the Coma spectrum in the 0.5-107 keV energy band can…

天体物理学 · 物理学 2009-11-13 A. A. Lutovinov , A. Vikhlinin , E. M. Churazov , M. G. Revnivtsev , R. A. Sunyaev

We report on results of two BeppoSAX observations of the Z source GX 17+2. In both cases the source is in the horizontal branch of the colour-intensity diagram. The persistent continuum can be fit by two-component models consisting of a…

天体物理学 · 物理学 2009-11-10 R. Farinelli , F. Frontera , A. A. Zdziarski , L. Stella , S. N. Zhang , M. van der Klis , N. Masetti , L. Amati

The detection of a nonthermal excess in the Coma cluster spectrum by two BeppoSAX observations analyzed with the XAS package (Fusco-Femiano et al.) has been disavowed by an analysis (Rossetti & Molendi) performed with a different software…

天体物理学 · 物理学 2009-11-11 Roberto Fusco-Femiano , Raffaella Landi , Mauro Orlandini

The brightest cluster radio halo known resides in the Coma cluster of galaxies. The relativistic electrons producing this diffuse synchrotron emission should also produce inverse Compton emission that becomes competitive with thermal…

宇宙学与河外天体物理 · 物理学 2011-02-11 Daniel R. Wik , Craig L. Sarazin , Alexis Finoguenov , Kyoko Matsushita , Kazuhiro Nakazawa , Tracy E. Clarke

RASS data near the North Galactic Pole was analyzed in order to study the large-scale distribution of soft X-ray emission from the Coma cluster. These RASS data constitute the only available X-ray observations of Coma that feature an in…

宇宙学与河外天体物理 · 物理学 2011-02-11 Max Bonamente , Richard Lieu , Esra Bulbul

Relativistic electrons, seen in the large diffuse radio halo of the Coma cluster of galaxies, should scatter background photons to higher energies. We calculate the inverse Compton contributions from the microwave background, from the local…

天体物理学 · 物理学 2011-05-23 Torsten A. Ensslin , Peter L. Biermann

Recent INTEGRAL observations and archival BeppoSAX data have been analyzed to deeply investigate the hard X-ray behavior of the neutron star, atoll type, low mass X-ray Binary 4U1636-53. Our investigation in three different periods outline…

天体物理学 · 物理学 2007-05-23 M. Fiocchi , A. Bazzano , P. Ubertini , M. federici

The RXTE satellite observed the Coma cluster for 177 ksec during November and December 2000, a second observation motivated by the intriguing results from the first 87 ksec observation in 1996. Analysis of the new dataset confirms that…

天体物理学 · 物理学 2009-11-07 Yoel Rephaeli , Duane Gruber

The radio spectral index map of the Coma halo shows a progressive steepening of the spectral index with increasing radius. Such a steepening cannot be simply justified by models involving continuous injection of fresh particles in the Coma…

天体物理学 · 物理学 2009-10-31 G. Brunetti , G. Setti , L. Feretti , G. Giovannini

A variety of models have been explored in regard to the origin of the excess extreme ultraviolet (~ 0.1 keV) emission in the Coma cluster. It is now established that the flux is non-thermal and the only non-thermal source mechanism that…

天体物理学 · 物理学 2007-05-23 Ming Yann Tsay , Chorng-Yuan Hwang , Stuart Bowyer

The aim of the present work is to constrain the Coma cluster magnetic field strength, its radial profile and power spectrum by comparing Faraday Rotation Measure (RM) images with numerical simulations of the magnetic field. We have analyzed…

宇宙学与河外天体物理 · 物理学 2015-05-18 A. Bonafede , L. Feretti , M. Murgia , F. Govoni , G. Giovannini , D. Dallacasa , K. Dolag , G. B. Taylor

Using the HEXTE experiment on-board the RXTE satellite, we performed a search for hard X-ray tails in Sco X-1 spectra. We found strong evidence for the presence of such a non-thermal component on several occasions. Using the PCA/RXTE we…

天体物理学 · 物理学 2009-11-06 F. D'Amico , W. A. Heindl , R. E. Rothschild , L. E. Peterson , D. E. Gruber , M. Pelling , J. A. Tomsick

The Coma cluster exhibits evidence for a high-energetic non-thermal particle population. At frequencies >1 GHz recent radio halo observations confirm a significant spectral steepening of the volume-integrated emission. We calculate the…

天体物理学 · 物理学 2009-11-10 A. Reimer , O. Reimer , R. Schlickeiser , A. Iyudin

We report results of a BeppoSAX (0.1-200 keV) observation of the Z-type low mass X-ray binary GX 17+2. The source was on the so-called Horizontal and Normal branches. Energy spectra were selected based on the source position in the X-ray…

‹ 上一页 1 2 3 10 下一页 ›