scholarly journals Radio and X-ray Study of SNRs in the Magellanic Clouds

1999 ◽  
Vol 192 ◽  
pp. 104-107
Author(s):  
M.D. Filipović ◽  
W. Pietsch ◽  
G. L. White ◽  
F. Haberl ◽  
L. Staveley-Smith ◽  
...  

We present our high-resolution radio-continuum and X-ray study of supernova remnants (SNRs) in the Magellanic Clouds (MCs). These investigations are based on Australia Telescope Compact Array (ATCA) radio-continuum and ROSAT X-ray observations. Our main aim is to study a complete sample of the MC SNRs and H II regions.

2020 ◽  
Vol 495 (1) ◽  
pp. 479-501 ◽  
Author(s):  
Thomas D Russell ◽  
Richard L White ◽  
Knox S Long ◽  
William P Blair ◽  
Roberto Soria ◽  
...  

ABSTRACT We present a new catalogue of radio sources in the face-on spiral galaxy M83. Radio observations taken in 2011, 2015, and 2017 with the Australia Telescope Compact Array at 5.5 and 9 GHz have detected 270 radio sources. Although a small number of these sources are background extragalactic sources, most are either H ii regions or supernova remnants (SNRs) within M83 itself. Three of the six historical supernovae are detected, as is the very young remnant that had been identified in a recent study, which is likely the result of a supernova that exploded in the last ∼100 yr but was missed. All of these objects are generally fading with time. Confusion limits our ability to measure the radio emission from a number of the SNRs in M83, but 64 were detected in unconfused regions, and these have the approximate power-law luminosity function that has been observed in other galaxies. The SNRs in M83 are systematically smaller in diameter and brighter than those that have been detected at radio wavelengths in M33. A number of the radio sources are coincident with X-ray sources in M83; most of these coincident sources turn out to be SNRs. Our dual frequency observations are among the most sensitive to date for a spiral galaxy outside the Local Group; despite this we were not able to place realistic constraints on the spectral indices, and as a result, it was not possible to search for SNRs based on their radio properties alone.


1984 ◽  
Vol 5 (4) ◽  
pp. 537-540 ◽  
Author(s):  
A. J. Turtle ◽  
B. Y. Mills

A catalogue of 38 supernova remnants (SNRs) identified in the Large and Small Magellanic Clouds from X-ray, optical and radio observations has recently been presented by Mills et al. (1984). One important consideration is the completeness of this catalogue and of the Galactic catalogues with which it is compared. These are currently being investigated.


1999 ◽  
Vol 190 ◽  
pp. 28-31 ◽  
Author(s):  
R. Chris Smith ◽  

The Magellanic Clouds are unique in providing sites to study the interstellar medium (ISM) and its components at all scales. To promote the pursuit of such studies, we have begun the Magellanic Cloud Emission-line Survey (MCELS), a deep imaging survey of both of these nearby galaxies in the emission of Hα, [S II], and [O III]. The emission-line images will be used in detailed optical and multiwavelength studies of H II regions, supernova remnants, planetary nebulae, superbubbles, and supergiant shells. Together with parallel surveys at other wavelengths, this survey will provide the foundation upon which to build a deeper understanding of the ISM in the Clouds and other galaxies, from small scales (~1 pc) all the way up to global scales. We present a sample of recent and current work using the MCELS dataset.


2011 ◽  
Vol 7 (S283) ◽  
pp. 334-335 ◽  
Author(s):  
Evan J. Crawford ◽  
Miroslav D. Filipović ◽  
Ivan S. Bojičić ◽  
Martin Cohen ◽  
Jeff L. Payne ◽  
...  

AbstractWe present preliminary results of our deep Australia Telescope Compact Array (ATCA) radio-continuum survey of the Magellanic Clouds Planetary Nebulae.


1983 ◽  
Vol 101 ◽  
pp. 289-293
Author(s):  
R. Petre ◽  
C. R. Canizares ◽  
P. F. Winkler ◽  
F. D. Seward ◽  
R. Willingale ◽  
...  

We present soft X-ray photomosaic images of two supernova remnants, Puppis A and IC 443, constructed from a series of exposures by the Einstein imaging instruments. The complex morphologies displayed in these images reflect the interaction between “middle-aged” supernova remnants and various components of the interstellar medium. Surface brightness variations across Puppis A suggest that inhomogeneities on scales from 0.2 to 30 pc are present in the interstellar medium, while the structure of IC 443 is apparently dominated by the interaction between the remnant and a giant molecular cloud.


2014 ◽  
Vol 1 (1) ◽  
pp. 200-204
Author(s):  
Satoru Katsuda ◽  
Hiroshi Tsunemi

High-resolution X-ray spectroscopy of Galactic supernova remnants (SNRs), based on grating spectrometers onboard XMM-Newton and Chandra, has been revealing a variety of new astrophysical phenomena. Broadened oxygen lines for a northwestern compact knot in SN 1006 clearly show a high oxygen temperature of ~300 keV. The high temperature together with a lower electron temperature (<em>kT<sub>e</sub></em> ~ 1 keV) can be reasonably interpreted as temperature non-equilibration between electrons and oxygen behind a collisionless shock. An ejecta knot in the Puppis A SNR shows blueshifted line emission by ~ 1500kms<sup>-1</sup>. The line widths are fairly narrow in contrast to the SN 1006's knot; an upper limit of 0.9 eV is obtained for O VIII Lyα, which translates to an oxygen temperature of <em>kT<sub>O</sub></em> &lt; 30 keV. The low temperature suggests that the knot was heated by a reverse shock whose velocity is 4 times slower than that of a forward shock. Anomalous intensity ratios in O VII Heα lines, i.e., a stronger forbidden line than a resonance line, is found in a cloud-shock interaction region in Puppis A. The line ratio can be best explained by the charge-exchange emission that should arise at interfaces between the cold/warm clouds and the hot plasma. There are several other targets for which we plan to analyze high-quality grating data prior to the operation of the soft X-ray spectrometer onboard Astro-H.


1983 ◽  
Vol 101 ◽  
pp. 343-346
Author(s):  
C. J. Salter ◽  
F. Mantovani ◽  
P. Tomasi

High resolution maps of the Galactic radio source CTB80 at three different frequencies are presented. A new interpretation in terms of a cosmic collision between two SNRs of different age is suggested.CTB80 is one of the most mystifying Galactic Objects yet discovered and has recently attracted considerable attention from X-ray, optical and radio astronomers (see for example: Becker et al. (1981), Angerhofer et al. (1980, 1981), Velusamy et al. (1976), van den Bergh (1980).The present observations of the radio continuum emission of the extended feature at 408 MHz, 1720 MHz and 4750 MHz and the linearly polarized emission at 1720 MHz and 4750 MHz (Figs 1,2,3) throw new light on the morphological, spectral and polarization properties of the whole source.


1996 ◽  
Vol 13 (2) ◽  
pp. 182-182
Author(s):  
Ray Norris

The 3 mm radio continuum emission from active galaxies consists of three components: (1)Synchrotron emission from the active galactic nucleus (AGN), which is over 1 Jy in 3C273 but which is not significant in most of the types of galaxy considered here.(2)Free–free emission from H II regions. The flux of this in a starburst galaxy is typically of the order of 10 mJy and could be imaged with a 3 mm-capable Australia Telescope Compact Array (ATCA).(3)Emission from the tail of the 50–100 K black-body spectrum of the dust. For example, the dust in Arp 220 (redshift of 0·02) at a temperature of 50 K has a flux of 30 mJy at 3 mm. Interestingly, this flux does not decrease substantially with redshift, as the decrease in brightness is compensated for by the redshifting of the steep edge of the blackbody curve, and so infrared-bright galaxies can be studied up to high redshifts with existing instruments.


1974 ◽  
Vol 60 ◽  
pp. 311-327 ◽  
Author(s):  
B. Y. Mills

A supernova event may lead to four observable features: a pulsar, an expanding nebulosity, a radio source and an X-ray source. The great majority of supernovae do not produce observable pulsars, and discussion is restricted largely to the other features. An increasing number of X-ray sources is now being detected and the structure and spectrum of the stronger sources investigated; these observations yield information about the physical state of the remnant. Recently, 11 new optical and radio remnants have been found in the Magellanic Clouds. These have led to a good determination of the Σ – D relation, thus providing a more reliable distance scale for galactic SNR, but have also shown that a one-to-one correspondence between a radio source and a supernova event is questionable. When these remnants are combined with corrected earlier catalogues and a new southern catalogue containing a high proportion of distant old remnants the number of known SNR is about 150. The evolution of galactic SNR may be investigated empirically, and although the derived rate of occurrence is very uncertain a rate of about 2 supernovae per century is consistent with most determinations. The galactic SNR are distributed rather like the radio disc emission, but more closely confined to the galactic plane, and selected SNR show evidence of a spiral pattern.


1988 ◽  
Vol 101 ◽  
pp. 99-114 ◽  
Author(s):  
B. Aschenbach

AbstractA review is given of recent observations of the X-ray emission from supernova remnants carried out on the Einstein, Tenma and EXOSAT satellites as well as from a few sounding rocket experiments. Our current interpretation of the high resolution images, high resolution energy spectra and the first few spectrally resolved images is discussed.


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