scholarly journals Historical Supernovae and Supernova Remnants

1996 ◽  
Vol 145 ◽  
pp. 323-331 ◽  
Author(s):  
Zhenru Wang
Keyword(s):  
Tang Dynasty ◽  
Supernova Remnants ◽  
Supernova Remnant ◽  
High Energy ◽  
X Rays ◽  
Supernovae And Supernova Remnants ◽  
X Ray ◽  
The Tang Dynasty ◽  
High Energy Emission ◽  
The Relationship

The oldest historical supernova (SN), recorded by ancient Chinese in 14th Century B.C. on pieces of tortoise shells or bones, is identified with the aid of modern space γ-ray observations. Hard X-rays with energy up to 20 keV were observed from IC 443 by the X-ray satellite Ginga. We infer from these observations the age of IC 443 is ∼ 1000 — 1400 yrs. The result supports the hypothesis that IC 443 is the remnant of the historical SN 837 that occurred during the Tang Dynasty. The association between the supernova remnant (SNR) CTB 80 and SN 1408 has been hotly debated for about ten years and is briefly reviewed and discussed here. A new picture is presented to explain this association. High energy emission from historical SNRs can persist in a multiphase interstellar medium (ISM). As a result, the study of the relationship between SNRs and ancient guest stars has gained new vitality.

scholarly journals Search for Nonthermal X-Rays from Supernova Remnant Shells

1998 ◽  
Vol 188 ◽  
pp. 117-120
Author(s):  
R. Petre ◽  
J. Keohane ◽  
U. Hwang ◽  
G. Allen ◽  
E. Gotthelf
Keyword(s):  
Radio Emission ◽  
Supernova Remnants ◽  
Supernova Remnant ◽  
Cosmic Ray ◽  
High Energy ◽  
X Rays ◽  
X Ray ◽  
Nonthermal Radio ◽  
Cosmic Ray Acceleration ◽  
Nonthermal Radio Emission

The suggestion that the shocks of supernova remnants (SNR's) are cosmic ray acceleration sites dates back more than 40 years. While observations of nonthermal radio emission from SNR shells indicate the ubiquity of GeV cosmic ray production, there is still theoretical debate about whether SNR shocks accelerate particles up to the well-known “knee” in the primary cosmic ray spectrum at ~3,000 TeV. Recent X-ray observations of SN1006 and other SNR's may have provided the missing observational link between SNR shocks and high energy cosmic ray acceleration. We discuss these observations and their interpretation, and summarize our ongoing efforts to find evidence from X-ray observations of cosmic ray acceleration in the shells of other SNR's.

scholarly journals The interstellar medium in young supernova remnants: key to the production of cosmic X-rays and $\gamma $-rays

2021 ◽  
Vol 366 (6) ◽  
Author(s):  
Hidetoshi Sano ◽  
Yasuo Fukui
Keyword(s):  
Interstellar Medium ◽  
Supernova Remnants ◽  
Cosmic Ray ◽  
High Energy ◽  
X Rays ◽  
Interstellar Gas ◽  
High Energy Radiation ◽  
Dense Cores ◽  
The Relationship ◽  
Turbulent Velocity Field

AbstractWe review recent progress in elucidating the relationship between high-energy radiation and the interstellar medium (ISM) in young supernova remnants (SNRs) with ages of ∼2000 yr, focusing in particular on RX J1713.7−3946 and RCW 86. Both SNRs emit strong nonthermal X-rays and TeV $\gamma $ γ -rays, and they contain clumpy distributions of interstellar gas that includes both atomic and molecular hydrogen. We find that shock–cloud interactions provide a viable explanation for the spatial correlation between the X-rays and ISM. In these interactions, the supernova shocks hit the typically pc-scale dense cores, generating a highly turbulent velocity field that amplifies the magnetic field up to 0.1–1 mG. This amplification leads to enhanced nonthermal synchrotron emission around the clumps, whereas the cosmic-ray electrons do not penetrate the clumps. Accordingly, the nonthermal X-rays exhibit a spatial distribution similar to that of the ISM on the pc scale, while they are anticorrelated at sub-pc scales. These results predict that hadronic $\gamma $ γ -rays can be emitted from the dense cores, resulting in a spatial correspondence between the $\gamma $ γ -rays and the ISM. The current pc-scale resolution of $\gamma $ γ -ray observations is too low to resolve this correspondence. Future $\gamma $ γ -ray observations with the Cherenkov Telescope Array will be able to resolve the sub-pc-scale $\gamma $ γ -ray distribution and provide clues to the origin of these cosmic $\gamma $ γ -rays.

scholarly journals Fermi-LAT and WMAP observations of the supernova remnant Puppis A

2013 ◽  
Vol 9 (S296) ◽  
pp. 295-299
Author(s):  
Marie-Hélène Grondin ◽  
John W. Hewitt ◽  
Marianne Lemoine-Goumard ◽  
Thierry Reposeur ◽  
Keyword(s):  
Supernova Remnants ◽  
Supernova Remnant ◽  
Gamma Ray ◽  
High Energy ◽  
Radio Spectrum ◽  
Wilkinson Microwave Anisotropy Probe ◽  
Large Area ◽  
X Ray ◽  
Inverse Compton Scattering ◽  
Γ Ray

AbstractThe supernova remnant (SNR) Puppis A (aka G260.4-3.4) is a middle-aged supernova remnant, which displays increasing X-ray surface brightness from West to East corresponding to an increasing density of the ambient interstellar medium at the Eastern and Northern shell. The dense IR photon field and the high ambient density around the remnant make it an ideal case to study in γ-rays. Gamma-ray studies based on three years of observations with the Large Area Telescope (LAT) aboard Fermi have revealed the high energy gamma-ray emission from SNR Puppis A. The γ-ray emission from the remnant is spatially extended, and nicely matches the radio and X-ray morphologies. Its γ-ray spectrum is well described by a simple power law with an index of ~2.1, and it is among the faintest supernova remnants yet detected at GeV energies. To constrain the relativistic electron population, seven years of Wilkinson Microwave Anisotropy Probe (WMAP) data were also analyzed, and enabled to extend the radio spectrum up to 93 GHz. The results obtained in the radio and γ-ray domains are described in detail, as well as the possible origins of the high energy γ-ray emission (Bremsstrahlung, Inverse Compton scattering by electrons or decay of neutral pions produced by proton interactions).

scholarly journals A New Chapter in Hard X-rays of the M87 AGN

Proceedings ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 9
Author(s):  
Ka-Wah Wong ◽  
Rodrigo S. Nemmen ◽  
Jimmy A. Irwin ◽  
Dacheng Lin
Keyword(s):  
High Energy ◽  
X Rays ◽  
X Ray ◽  
Accretion Flow ◽  
Relativistic Jet ◽  
Very High Energy ◽  
Γ Ray ◽  
High Energy Emission ◽  
First Time ◽  
Very High

The nearby M87 hosts an exceptional relativistic jet. It has been regularly monitored in radio to TeV bands, but little has been done in hard X-rays ≳10 keV. For the first time, we have successfully detected hard X-rays up to 40 keV from its X-ray core with joint Chandra and NuSTAR observations, providing important insights to the X-ray origins: from the unresolved jet or the accretion flow. We found that the hard X-ray emission is significantly lower than that predicted by synchrotron self-Compton models introduced to explain very-high-energy γ -ray emission above a GeV. We discuss recent models to understand these high energy emission processes.

scholarly journals Sources of X-rays from galaxies

2011 ◽  
Vol 7 (S284) ◽  
pp. 183-192
Author(s):  
Q. Daniel Wang
Keyword(s):  
Active Galactic Nuclei ◽  
Galaxy Evolution ◽  
Supernova Remnants ◽  
Large Scale ◽  
Formation Rate ◽  
Galactic Nuclei ◽  
High Energy ◽  
High Mass ◽  
X Rays ◽  
X Ray

AbstractGalactic X-ray emission is a manifestation of various high-energy phenomena and processes. The brightest X-ray sources are typically accretion-powered objects: active galactic nuclei and low- or high-mass X-ray binaries. Such objects with X-ray luminosities of ≳ 1037 ergs s−1 can now be detected individually in nearby galaxies. The contributions from fainter discrete sources (including cataclysmic variables, active binaries, young stellar objects, and supernova remnants) are well correlated with the star formation rate or stellar mass of galaxies. The study of discrete X-ray sources is essential to our understanding of stellar evolution, dynamics, and end-products as well as accretion physics. With the subtraction of the discrete source contributions, one can further map out truly diffuse X-ray emission, which can be used to trace the feedback from active galactic nuclei, as well as from stars, both young and old, in the form of stellar winds and supernovae. The X-ray emission efficiency, however, is only about 1% of the energy input rate of the stellar feedback alone. The bulk of the feedback energy is most likely gone with outflows into large-scale galactic halos. Much is yet to be investigated to comprehend the role of such outflows in regulating the ecosystem, hence the evolution of galaxies. Even the mechanism of the diffuse X-ray emission remains quite uncertain. A substantial fraction of the emission cannot arise directly from optically-thin thermal plasma, as commonly assumed, and most likely originates in its charge exchange with neutral gas. These uncertainties underscore our poor understanding of the feedback and its interplay with the galaxy evolution.

scholarly journals The High Energy X-ray Spectra of Supernova Remnants

1983 ◽  
Vol 101 ◽  
pp. 29-36
Author(s):  
Steven H. Pravdo ◽  
John J. Nugent
Keyword(s):  
Lower Energy ◽  
Supernova Remnants ◽  
High Energy ◽  
X Rays ◽  
Energy Data ◽  
X Ray ◽  
Ionization Structure ◽  
Continuum Contribution ◽  
Cas A ◽  
Ionization Nonequilibrium

We present the results of fitting an ionization nonequilibrium (NIE) model to the high energy (> 5 keV) X-ray spectra of the young supernova remnants Cas A and Tycho. As an additional constraint, we demand that the models simultaneously fit lower energy, higher resolution data. For Cas A, a single NIE component can not adequately reproduce the features for the entire X-ray spectrum because 1) the ionization structure of iron ions responsible for the K emission is inconsistent with that of the ions responsible for the lower energy lines, and 2) the flux of the highest energy X-rays is underestimated. The iron K line and the high energy continuum could arise from the same NIE component but the identification of this component with either the blast wave or the ejecta in the “standard” model is difficult. In Tycho, the high energy data rule out a class of models for the lower energy data which have too large a continuum contribution.

scholarly journals Thermal Or Non–Thermal X–Rays From AGNs?

1994 ◽  
Vol 159 ◽  
pp. 33-36
Author(s):  
Gabriele Ghisellini ◽  
Francesco Haardt
Keyword(s):  
High Energy ◽  
Spectral Shape ◽  
X Rays ◽  
Two Phase ◽  
X Ray ◽  
Galactic Black Hole ◽  
Phase Models ◽  
Hot Corona ◽  
High Energy Emission ◽  
Cold Matter

Recent data from OSSE on CGRO and SIGMA on GRANAT challenge the non-thermal interpretation of the origin of the high energy emission of AGNs, showing that the hard X-ray spectra of several Seyfert AGN are steep like those of Galactic black hole candidates. Thermal models are therefore favoured. Two–phase models, in which a hot corona is placed above a relatively cold accretion disk can account for the observed X–ray spectra and the correlated variability in the UV and X–ray bands. Cold matter, both in the vicinity of the nucleous, and located further away in the torus surrounding the nucleous, may modify substantially the spectrum with important consequences on the expected variability and spectral shape.

scholarly journals Possible Contributions of Supernova Remnants to the Soft X-ray Diffuse Background (0.1 - 1 keV)

1983 ◽  
Vol 101 ◽  
pp. 361-365
Author(s):  
W. T. Sanders ◽  
D. N. Burrows ◽  
D. McCammon ◽  
W. L. Kraushaar
Keyword(s):  
Supernova Remnants ◽  
Large Scale ◽  
Supernova Remnant ◽  
Galactic Halo ◽  
Galactic Plane ◽  
X Rays ◽  
X Ray ◽  
Band Emission ◽  
Diffuse Background ◽  
Almost All

Almost all of the B band (0.10–0.19 keV) and C band (0.15–0.28 keV) X-rays probably originate in a hot region surrounding the Sun, which Cox and Anderson have modeled as a supernova remnant. This same region may account for a significant fraction of the M band (0.5–1 keV) X-rays if the nonequilibrium models of Cox and Anderson are applicable. A population of distant SNR similar to the local region, with center-to-center spacing of about 300 pc, could provide enough galactic M band emission to fill in the dip in the count rate in the galactic plane that would otherwise be present due to absorption of both the extra-galactic power law flux and any large-scale-height stellar (or galactic halo) emission.

scholarly journals The X-ray properties of magnetic massive stars

2014 ◽  
Vol 9 (S307) ◽  
pp. 437-442
Author(s):  
Yaël Nazé ◽  
Véronique Petit ◽  
Melanie Rinbrand ◽  
David Cohen ◽  
Stan Owocki ◽  
...  
Keyword(s):  
Massive Stars ◽  
Mass Loss Rate ◽  
High Energy ◽  
Strongly Correlated ◽  
X Rays ◽  
X Ray ◽  
Magnetically Confined ◽  
Higher Temperature ◽  
Early Type Stars ◽  
High Energy Emission

AbstractEarly-type stars are well-known to be sources of soft X-rays. However, this high-energy emission can be supplemented by bright and hard X-rays when magnetically confined winds are present. In an attempt to clarify the systematics of the observed X-ray properties of this phenomenon, a large series of Chandra and XMM observations was analyzed, over 100 exposures of 60% of the known magnetic massive stars listed recently by Petit et al. (2013). It is found that the X-ray luminosity is strongly correlated with mass-loss rate, in agreement with predictions of magnetically confined wind models, though the predictions of higher temperature are not always verified. We also investigated the behaviour of other X-ray properties (absorption, variability), yielding additional constraints on models. This work not only advances our knowledge of the X-ray emission of massive stars, but also suggests new observational and theoretical avenues to further explore magnetically confined winds.

scholarly journals A source of gamma rays coincident with the shell of the supernova remnant CTB 80

2021 ◽  
Vol 502 (1) ◽  
pp. 472-477
Author(s):  
M Araya ◽  
C Herrera
Keyword(s):  
Gamma Rays ◽  
Supernova Remnant ◽  
Gamma Ray ◽  
Cosmic Ray ◽  
High Energy ◽  
Large Area ◽  
Extended Source ◽  
X Ray ◽  
Extended Radio ◽  
High Energy Emission

ABSTRACT CTB 80 (G69.0+2.7) is a relatively old (50–80 kyr) supernova remnant (SNR) with a complex radio morphology showing three extended radio arms and a radio and X-ray nebula near the location of the pulsar PSR B1951+32. We report on a study of the GeV emission in the region of CTB 80 with Fermi-Large Area Telescope data. An extended source with a size of 1.3°, matching the size of the infrared shell associated to the SNR, was discovered. The GeV emission, detected up to an energy of ∼20 GeV, is more significant at the location of the northern radio arm where previous observations imply that the SNR shock is interacting with ambient material. Both hadronic and leptonic scenarios can reproduce the multiwavelength data reasonably well. The hadronic cosmic ray energy density required is considerably larger than the local Galactic value and the gamma-ray leptonic emission is mainly due to bremsstrahlung interactions. We conclude that GeV particles are still trapped or accelerated by the SNR producing the observed high-energy emission when interacting with ambient material.

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