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Related papers: Small-Scale X-ray Variability in the Cassiopeia A …

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The young SNR Cassiopeia A was imaged with WFPC-2 through four filters selected to capture the complete velocity range of the remnant's main shell in several important emission lines. Primary lines detected were [O III] 4959,5007, [N II]…

The study on the dynamic evolution of young supernova remnants (SNRs) is an important way to understand the density structure of the progenitor's circumstellar medium. We have reported the acceleration or deceleration, proper motion and…

Astrophysics of Galaxies · Physics 2022-12-14 Xianhuan Lei , Hui Zhu , Haiyan Zhang , Wenwu Tian

We present an update on the results of our monitoring observations of the X-ray remnant of supernova (SN) 1987A with the {\it Chandra X-Ray Observatory}. As of 2002 December, we have performed a total of seven observations of SN 1987A. The…

The thermal evolution of young neutron stars (NSs) reflects the neutrino emission properties of their cores. Heinke et al. (2010) measured a 3.6+/-0.6% decay in the surface temperature of the Cassiopeia A (Cas A) NS between 2000 and 2009,…

High Energy Astrophysical Phenomena · Physics 2015-06-16 K. G. Elshamouty , C. O. Heinke , G. R. Sivakoff , W. C. G. Ho , P. S. Shternin , D. G. Yakovlev , D. J. Patnaude , L. David

We discuss the X-ray emission observed from Supernova Remnant 1987A with the Chandra X-ray Observatory. We analyze a high resolution spectrum obtained in 1999 October with the high energy transmission grating (HETG). From this spectrum we…

Hubble Space Telescope images of the young Galactic supernova remnant Cassiopeia A reveal a far larger population of outlying, high-velocity knots of ejecta with a broader range of chemical properties than previously suspected. We identify…

The spectacular first light observation by the Chandra X-Ray Observatory revealed an X-ray point source near the center of the 300 yr old Cas A supernova remnant. We present an analysis of the public X-ray spectral and timing data. No…

We used the Spitzer Space Telescope's Infrared Spectrograph to map nearly the entire extent of Cassiopeia A between 5-40 micron. Using infrared and Chandra X-ray Doppler velocity measurements, along with the locations of optical ejecta…

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

We investigate the effect of the circumstellar medium density profile on the X-ray emission from outer ejecta knots in the Cassiopeia A supernova remnant using the 1 Ms Chandra observation. The spectra of a number of radial series of ejecta…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Una Hwang , J. Martin Laming

We consider in more detail a model previously proposed for the hard X-ray (>10 keV) emission observed from the supernova remnant Cas A, whereby electrons are accelerated by lower-hybrid waves and radiate bremsstrahlung. We consider both…

Astrophysics · Physics 2009-11-07 J. Martin Laming

We analyze and model the infrared spectrum of the Cassiopeia A supernova remnant, with the aim of determining the masses of various elements in the unshocked ejecta. In this way we complement the survey of the X-ray emitting ejecta of Hwang…

High Energy Astrophysical Phenomena · Physics 2020-12-02 J. Martin Laming , Tea Temim

In this paper, we present updated estimates of the velocity of the neutron star (NS) in the supernova remnant (SNR) Cassiopeia A using over two decades of Chandra observations. We use two methods: 1.) recording NS positions from dozens of…

High Energy Astrophysical Phenomena · Physics 2025-01-23 Tyler Holland-Ashford , Patrick Slane , Xi Long

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…

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

We present high spatial resolution X-ray spectroscopy of supernova remnant Cassiopeia A with the {\sl Chandra} observations. The X-ray emitting region of this remnant was divided into 38 $\times$ 34 pixels with a scale of 10$\arcsec$…

Astrophysics · Physics 2009-11-13 Xue-juan Yang , Fang-jun Lu , Li Chen

We present the first results of an XMM-Newton observation of the central X-ray source in the Cas A supernova remnant. The spectrum can be fit equally well with an absorbed steep power law (alpha~3, N_H~1.5x10^22 cm^-2) or with a…

Astrophysics · Physics 2009-11-07 S. Mereghetti , A. Tiengo , G. L. Israel

We report Chandra observations of the highly asymmetric core-collapse supernova remnant G350.1-0.3. We document expansion over 9 years away from the roughly stationary central compact object, with sky-plane velocities up to $5000 d_{4.5}$…

High Energy Astrophysical Phenomena · Physics 2020-12-23 K. J. Borkowski , W. Miltich , S. P. Reynolds

We report on the study of six Chandra observations (four epochs) of the Central Compact Object (CCO) in the Cassiopeia A supernova remnant with the ACIS instrument in the subarray mode. This mode minimizes spectrum-distorting instrumental…

High Energy Astrophysical Phenomena · Physics 2022-06-29 B. Posselt , G. G. Pavlov

The supernova remnant Cassiopeia A (Cas A) is one of the few remnants in which it is possible to observe unshocked ejecta. A deep 1.64 micron image of Cas A shows a patch of diffuse emission from unshocked ejecta, as well as brighter…

Astrophysics of Galaxies · Physics 2018-10-31 J. C. Raymond , B. -C. Koo , Y. -H. Lee , D. Milisavljevic , R. A. Fesen , I. Chilingarian