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Related papers: Hard X-ray emissions from Cassiopeia A observed by…

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X-ray synchrotron radiation is expected to be highly polarized. Thanks to the Imaging X-ray Polarimetry Explorer (IXPE), it is now possible to evaluate the degree of X-ray polarization in sources such as supernova remnants (SNRs). Jointly…

High Energy Astrophysical Phenomena · Physics 2025-04-10 Alessandra Mercuri , Emanuele Greco , Jacco Vink , Riccardo Ferrazzoli , Silvia Perri

We report 32 GHz absolute flux density measurements of the supernova remnant Cas A, with an accuracy of 2.5%. The measurements were made with the 1.5-meter telescope at the Owens Valley Radio Observatory. The antenna gain had been measured…

We report on the results of a deep 1.6 Ms INTEGRAL observation of the Cassiopeia region performed from December 2003 to February 2004. Eleven sources were detected with the imager IBIS-ISGRI at energies above 20 keV, including three new…

Astrophysics · Physics 2009-11-11 P. R. den Hartog , W. Hermsen , L. Kuiper , J. Vink , J. J. M. in 't Zand , W. Collmar

We introduce a million-second observation of the supernova remnant Cassiopeia A with the Chandra X-ray Observatory. The bipolar structure of the Si-rich ejecta (NE jet and SW counterpart) is clearly evident in the new images, and their…

Supernova remnants may exhibit both thermal and nonthermal X-ray emission. Such remnants can be distinguished by the weakness of their X-ray lines, because of the presence of a strong nonthermal X-ray continuum. RCW 86 is a remnant with…

Astrophysics · Physics 2009-10-31 K. J. Borkowski , J. Rho , S. P. Reynolds , K. K. Dyer

Characterizing the ejecta in young supernova remnants is a requisite step towards a better understanding of stellar evolution. In Cassiopeia A the density and total mass remaining in the unshocked ejecta are important parameters for…

Astrophysics of Galaxies · Physics 2015-06-18 Tracey DeLaney , Namir E. Kassim , Lawrence Rudnick , R. A. Perley

Aims: Archival observations of infrared fine-structure lines of the young Galactic supernova remnant Cassiopeia A allow us to test existing models and determine the physical parameters of various regions of the fast-moving knots (FMKs),…

Astrophysics · Physics 2010-04-08 D. Docenko , R. A. Sunyaev

The remnant of SN 1006 has an X-ray spectrum dominated by nonthermal emission, and pre-ASCA observations were well described by a synchrotron calculation with electron energies limited by escape. We describe the results of a much more…

Astrophysics · Physics 2009-10-31 K. K. Dyer , S. P. Reynolds , K. J. Borkowski , G. E. Allen , R. Petre

HST ACS images of the young SN remnant Cas A are used to explore the expansion and spatial distribution of its highest velocity debris. Proper motions of over 1800 outlying ejecta knots are reported. The distribution of transverse expansion…

We present the results of extinction measurements toward the main ejecta shell of the Cassiopeia A supernova (SN) remnant using the flux ratios between the two near-infrared (NIR) [Fe II] lines at 1.26 and 1.64 $\mu {\rm m}$. We find a…

Astrophysics of Galaxies · Physics 2015-08-06 Yong-Hyun Lee , Bon-Chul Koo , Dae-Sik Moon , Jae-Joon Lee

We present a comparative analysis of supernova remnant Cassiopeia A based on two deep, narrow-band images covering the [Fe II] 1.644um + [Si I] 1.645um lines obtained in 2013 and 2020 with the same instruments on the UKIRT 3.8m telescope.…

High Energy Astrophysical Phenomena · Physics 2026-02-11 Seung-Hoon Jung , Bon-Chul Koo , Yong-Hyun Lee , Hyun-Jeong Kim , Jae-Joon Lee

gamma Cassiopeiae (gCas) is a B0.5e star with peculiar X-ray emission properties and yet the prototype of its own small class. In this paper we examine the X-ray spectra for a 2004 XMM-Newton observation and a previously published 2001…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Raimundo Lopes de Oliveira , Myron A. Smith , Christian Motch , ;

Flux calibrated images of the known supernova remnant G 34.7-0.4 in basic optical emission lines are presented. The low ionization images show a relatively flat flux distribution. The diffuse and patchy morphology of the detected optical…

Astrophysics · Physics 2009-11-07 Fotis Mavromatakis , Panayotis Boumis , Christos D. Goudis

We use new large area far infrared maps ranging from 65 - 500 microns obtained with the AKARI and the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) missions to characterize the dust emission toward the Cassiopeia A supernova…

We revisit the average hard X-ray spectrum from the AGN of Centaurus A (Cen A) using ten years worth of observations with INTEGRAL SPI. This source has the highest flux observed from any AGN in the SPI bandpass (23 keV--8 MeV). The 10 year…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Mark J. Burke , Elisabeth Jourdain , Jean-Pierre Roques , Daniel A. Evans

The observed anomalous steady decrease in surface temperature of the supernova remnant Cassiopeia A (Cas A), which was reported about ten years ago, has generated much debate. Several exotic cooling scenarios have been proposed using…

High Energy Physics - Phenomenology · Physics 2021-10-20 Lev B. Leinson

We examine observed heavy element abundances in the Cassiopeia A supernova remnant as a constraint on the nature of the Cas A supernova. We compare bulk abundances from 1D and 3D explosion models and spatial distribution of elements in 3D…

Young supernova remnants (SNRs) provide crucial insights into explosive nucleosynthesis products and their velocity distribution soon after the explosion. However, these velocities are influenced by the dynamics of the circumstellar medium…

The explosion mechanism behind Type Ia supernovae is a matter of continuing debate. The diverse attempts to identify or at least constrain the physical processes involved in the explosion have been only partially successful so far. In this…

Astrophysics · Physics 2009-11-07 Carles Badenes , Eduardo Bravo , Kazimierz J. Borkowski , Inmaculada Dominguez

We present the analysis of archival data from the Advanced Satellite for Cosmology and Astrophysics} (ASCA) of the supernova remnant (SNR) G39.2-0.3. G39.2-0.3 has been sometimes characterized as a shell-like remnant in the literature but…

Astrophysics · Physics 2009-10-31 I. M. Harrus , P. O. Slane