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Related papers: Secular Decrease and Random Variations of Cassiope…

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We present seven years of radio observations of SN 1987A made with the Australia Telescope Compact Array. At 1.4, 2.4, 4.8 and 8.6 GHz, the flux density of the radio remnant has increased monotonically since emission was redetected 1200…

The accretion-powered millisecond X-ray pulsar, SAX J1808.4-3658, was observed in quiescence with ASCA in September 1999. We detected a dim X-ray source in the SIS data at the position consistent to SAX J1808.4-3658. The source count rate…

Astrophysics · Physics 2009-10-31 Tadayasu Dotani , Kazumi Asai , Rudy Wijnands

We have analysed the full suite of Australia Telescope Compact Array data for the Stingray planetary nebula. Data were taken in the 4- to 23-GHz range of radio frequencies between 1991 and 2016. The radio flux density of the nebula…

We present the first results on the hard X-ray continuum image (up to 15 keV) of the supernova remnant Cas A measured with the EPIC cameras onboard XMM-Newton. The data indicate that the hard X-ray tail, observed previously, that extends to…

We calculate particle spectra and continuum photon emission from the Cassiopeia A supernova remnant (SNR). The particle spectra, ion and electron, result from diffusive shock acceleration at the forward SNR shock and are determined with a…

This paper presents the analysis of Doppler p-mode observations of the G2V star $\alpha$ Cen A obtained with the spectrograph CORALIE in May 2001. Thirteen nights of observations have made it possible to collect 1850 radial velocity…

Astrophysics · Physics 2016-08-30 F. Bouchy , F. Carrier

We observed a nearby radio galaxy, the Centaurus A (Cen A), three times with Suzaku in 2009, and measured the wide-band X-ray spectral variability more accurately than the previous measurements. The Cen A was in the active phase in 2009,…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Y. Fukazawa , K. Hiragi , S. Yamazaki , M. Mizuno , K. Hayashi , K. Hayashi , S. Nishino , H. Takahashi , M. Ohno

Cassiopeia A was observed using the Low-Band Antennas of the LOw Frequency ARray (LOFAR) with high spectral resolution. This allowed a search for radio recombination lines (RRLs) along the line-of-sight to this source. Five carbon-alpha…

It is widely believed that the bulk of the Galactic cosmic rays are accelerated in supernova remnants (SNRs). However, no observational evidence of the presence of particles of PeV energies in SNRs has yet been found. The young historical…

High Energy Astrophysical Phenomena · Physics 2020-01-30 MAGIC Collaboration , M. L. Ahnen , S. Ansoldi , L. A. Antonelli , C. Arcaro , A. Babić , B. Banerjee , P. Bangale , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , E. Bernardini , A. Berti , W. Bhattacharyya , B. Biasuzzi , A. Biland , O. Blanch , S. Bonnefoy , G. Bonnoli , R. Carosi , A. Carosi , A. Chatterjee , S. M. Colak , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Cumani , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , E. de Oña Wilhelmi , F. Di Pierro , M. Doert , A. Domínguez , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Eisenacher Glawion , D. Elsaesser , M. Engelkemeier , V. Fallah Ramazani , A. Fernández-Barral , D. Fidalgo , M. V. Fonseca , L. Font , C. Fruck , D. Galindo , R. J. García López , M. Garczarczyk , M. Gaug , P. Giammaria , N. Godinović , D. Gora , D. Guberman , D. Hadasch , A. Hahn , T. Hassan , M. Hayashida , J. Herrera , J. Hose , D. Hrupec , T. Inada , K. Ishio , Y. Konno , H. Kubo , J. Kushida , D. Kuveždić , D. Lelas , E. Lindfors , S. Lombardi , F. Longo , M. López , C. Maggio , P. Majumdar , M. Makariev , G. Maneva , M. Manganaro , K. Mannheim , L. Maraschi , M. Mariotti , M. Martínez , D. Mazin , U. Menzel , M. Minev , R. Mirzoyan , A. Moralejo , V. Moreno , E. Moretti , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , K. Nilsson , D. Ninci , K. Nishijima , K. Noda , L. Nogués , S. Paiano , J. Palacio , D. Paneque , R. Paoletti , J. M. Paredes , G. Pedaletti , M. Peresano , L. Perri , M. Persic , P. G. Prada Moroni , E. Prandini , I. Puljak , J. R. Garcia , I. Reichardt , W. Rhode , M. Ribó , J. Rico , C. Righi , T. Saito , K. Satalecka , S. Schroeder , T. Schweizer , S. N. Shore , J. Sitarek , I. Šnidarić , D. Sobczynska , A. Stamerra , M. Strzys , T. Surić , L. Takalo , F. Tavecchio , P. Temnikov , T. Terzić , D. Tescaro , M. Teshima , N. Torres-Albà , A. Treves , G. Vanzo , M. Vazquez Acosta , I. Vovk , J. E. Ward , M. Will , D. Zarić

Spectroscopic observations at 2.4 - 45 microns of the young supernova remnant Cas A with the Infrared Space Observatory (ISO) Short Wavelength Spectrometer (SWS) reveal strong emission lines of O, Ne, Si, S, and Ar. These lines are observed…

Astrophysics · Physics 2009-10-31 R. G. Arendt , E. Dwek , S. H. Moseley

The Central Compact Object (CCO) in the Cassiopeia A supernova remnant is most likely a very young ($\approx 300$ yr) neutron star. If a previously reported decrease of its surface temperature by 4% in 10 years could be confirmed, it would…

High Energy Astrophysical Phenomena · Physics 2018-09-19 B. Posselt , G. G. Pavlov

The cooling rate of young neutron stars gives direct insight into their internal makeup. Although the temperatures of several young neutron stars have been measured, until now a young neutron star has never been observed to decrease in…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Craig O. Heinke , Wynn C. G. Ho

Based on the IUE SWP spectra obtained between 1978 and 1994, the variations of the UV continuum and the Ly-alpha and C IV emission lines of the broad-line radio galaxy 3C390.3 are studied. The UV continuum between 1220 and 1990 A has varied…

Astrophysics · Physics 2009-10-28 Wei Zheng

We present a long-exposure (~10 hr) image of the supernova (SN) remnant Cassiopeia A (Cas A) obtained with the UKIRT 3.8-m telescope using a narrow band filter centered at 1.644 um emission. The passband contains [Fe II] 1.644 um and [Si I]…

Astrophysics of Galaxies · Physics 2018-10-31 Bon-Chul Koo , Hyun-Jeong Kim , Yong-Hyun Lee , John C. Raymond , Jae-Joon Lee , Sung-Chul Yoon , Dae-Sik Moon

In this paper, we focus on the limb-brightened, prolate spheroidal cavity of the radio galaxy Cygnus A, as revealed by the Chandra X-ray Observatory. We use the shock heated, thermal intracluster medium around the expanding cavity to infer…

Astrophysics · Physics 2009-11-11 A. S. Wilson , David A. Smith , A. J. Young

We present the results of daily monitoring of 6.7 GHz methanol maser in Cepheus A (Cep A) using Yamaguchi 32-m radio telescope as well as the results of imaging observations conducted with the JVN (Japanese VLBI Network). We indentified…

We present high-resolution X-ray proper motion measurements of Cassiopeia A using Chandra observations from 2000 and 2002. We separate the emission into four spectrally distinct classes: Si-dominated, Fe-dominated, low-energy-enhanced, and…

Astrophysics · Physics 2009-11-10 T. DeLaney , L. Rudnick , R. Fesen , T. W. Jones , R. Petre , J. A. Morse

Gamma Cassiopeiae is an enigmatic Be star with unusually strong hard X-ray emission. The Suzaku observatory detected six rapid X-ray spectral hardening events called "softness dips" in a ~100 ksec duration observation in 2011. All the…

High Energy Astrophysical Phenomena · Physics 2016-12-07 K. Hamaguchi , L. Oskinova , C. M. P. Russell , R. Petre , T. Enoto , K. Morihana , M. Ishida

Theoretical models predict that core-collapse supernovae (CCSNe) can be efficient dust producers (0.1-1.0 Msun), potentially accounting for most of the dust production in the early Universe. Observational evidence for this dust production…

Astrophysics of Galaxies · Physics 2017-01-25 I. De Looze , M. J. Barlow , B. M. Swinyard , J. Rho , H. L. Gomez , M. Matsuura , R. Wesson
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