scholarly journals High-energy Emission from Supernovae and Remnants

2000 ◽  
Vol 195 ◽  
pp. 135-142
Author(s):  
R. A. Chevalier

An early burst of energetic radiation is expected from a supernova at the time of shock breakout. This emission has not been directly observed but has been inferred from the photoionization around SN 1987A. X-ray emission has been detected from core-collapse supernovae in the days to years after the explosion as they interact with their circumstellar winds. Young Galactic supernova remnants provide the possibility of determining the composition structure of the ejecta through X-ray spectroscopy. An exciting finding for older remnants is that a number of remnants that appear to be interacting with molecular gas may be sources of high-energy γ-ray emission. The clumpy structure of molecular clouds has implications for the structure expected in high-energy emission. Finally, the field of γ-ray-line spectroscopy is beginning to yield results relevant to the explosive nucleosynthesis of radionuclides in supernovae.

2020 ◽  
Vol 494 (4) ◽  
pp. 6043-6052
Author(s):  
S del Palacio ◽  
F García ◽  
D Altamirano ◽  
R H Barbá ◽  
V Bosch-Ramon ◽  
...  

ABSTRACT We conducted an observational campaign towards one of the most massive and luminous colliding wind binaries in the Galaxy, HD 93129A, close to its periastron passage in 2018. During this time the source was predicted to be in its maximum of high-energy emission. Here we present our data analysis from the X-ray satellites Chandra and NuSTAR and the γ-ray satellite AGILE. High-energy emission coincident with HD 93129A was detected in the X-ray band up to ∼18 keV, whereas in the γ-ray band only upper limits were obtained. We interpret the derived fluxes using a non-thermal radiative model for the wind-collision region. We establish a conservative upper limit for the fraction of the wind kinetic power that is converted into relativistic electron acceleration, fNT,e < 0.02. In addition, we set a lower limit for the magnetic field in the wind-collision region as BWCR > 0.3 G. We also argue a putative interpretation of the emission from which we estimate fNT,e ≈ 0.006 and BWCR ≈ 0.5 G. We conclude that multiwavelength, dedicated observing campaigns during carefully selected epochs are a powerful tool for characterizing the relativistic particle content and magnetic field intensity in colliding wind binaries.


1996 ◽  
Vol 160 ◽  
pp. 331-338 ◽  
Author(s):  
Roger W. Romani

AbstractRecent X-ray and γ-ray observations have detected a number of isolated spin-powered pulsars. Studies of the pulse profiles of these objects are providing a useful guide to the site of the high energy emission. The γ-ray pulses, which are closely tied to the primary population of radiating particles, seem to be an especially useful discriminant between pulsar models. With an understanding of how the pulsar luminosity and beaming factors evolve with spin parameters, pulsar population syntheses can also be used to check the predictions of high energy emission models. In turn, comparison with γ-ray sky surveys constrains the properties of the young pulsar population.


2013 ◽  
Vol 9 (S296) ◽  
pp. 295-299
Author(s):  
Marie-Hélène Grondin ◽  
John W. Hewitt ◽  
Marianne Lemoine-Goumard ◽  
Thierry Reposeur ◽  

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).


Proceedings ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 9
Author(s):  
Ka-Wah Wong ◽  
Rodrigo S. Nemmen ◽  
Jimmy A. Irwin ◽  
Dacheng Lin

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.


2014 ◽  
Vol 10 (S313) ◽  
pp. 225-230
Author(s):  
Giulia Migliori

AbstractWe present a multiwavelength study of the core and relativistic jet of the radio loud (RL) quasar RGB J1512+020A (z=0.20). We report the discovery of a bright, 13” extended X-ray jet with a short Chandra observation. We discuss the origin of the jet X-ray emission and its properties in comparison with sample of X-ray quasar jets. The broadband core spectrum is contributed by the emission of the central quasar, by a blazar component, responsible for the γ-ray emission detected by Fermi, and by the host galaxy. We model the non-thermal blazar spectral energy distribution (SED) and constrain the total jet power. The jet power inferred from the blazar SED modeling is in agreement with the values obtained from the total radio power, pointing to a jet that efficiently carries its power up to kiloparsec scales. The quasar emission appears intrinsically weak in the optical-UV band. The disk luminosity estimated from the broad emission lines is lower than the jet power, in agreement with recent results from observations and theory.


2010 ◽  
Vol 19 (06) ◽  
pp. 791-796
Author(s):  
MANEL PERUCHO ◽  
VALENTÍ BOSCH-RAMON ◽  
DMITRY KHANGULYAN

We present the first three-dimensional simulations of the evolution of a microquasar jet inside the binary star system. The aim is to study the interaction of these jets with the stellar wind from a massive companion and the possible locations of high-energy emission sites. We have simulated two jets with different injection power in order to give a hint on the minimum power required for the jet to escape the system and become visible in larger scales. In the setup, we include a massive star wind filling the grid through which the jet evolves. We show that jets should have powers of the order of 1037 erg s-1 or more in order not to be destroyed by the stellar wind. The jet–wind interaction results in regions in which high-energy emission could be produced. These results imply the possible existence of a population of X–ray binaries undetected in the radio band due to jet disruption inside the region dominated by the stellar wind.


2018 ◽  
Vol 14 (S342) ◽  
pp. 176-179
Author(s):  
Giulia Migliori

AbstractObservations at high-energies are important to define the first stages of the evolution of extragalactic radio sources and to characterize the interstellar medium of their host galaxies. In some of the X-ray-observed Compact Symmetric Objects (CSOs, among the youngest and most compact radio galaxies), we measured values of the total hydrogen column densities large enough to slow or prevent the radio source growth. The γ-ray window has the potential to constrain the non-thermal contribution of jets and lobes to the total high-energy emission. However, so far, young radio sources remain elusive in γ-rays, with only a handful of detections (or candidates) reported by Fermi. I present our γ-ray study of the CSO PKS 1718–649, and draw comparison with the restarted, γ-ray detected, radio galaxy 3C 84.


1996 ◽  
Vol 145 ◽  
pp. 323-331 ◽  
Author(s):  
Zhenru Wang

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.


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