Jets associated with supernova remnants and other galactic nonthermal sources

1986 ◽  
Vol 64 (4) ◽  
pp. 482-483
Author(s):  
R. H. Becker

Accreting neutron star or black holes in binary systems can, under appropriate circumstances, eject jets of particles into their environment. This is most readily observed in SS433, Sco X-1, and Cyg X-3. We infer the presence of the injection of relativistic particles in a number of other galactic sources where actual jets have not been observed. In some cases the energy imparted results in nonthermal radio sources comparable in size to supernova remnants.

Author(s):  
RESHMI MUKHERJEE

VERITAS is an array of four imaging atmospheric Cherenkov telescopes located in southern Arizona, and is now starting its fifth year of observations of the northern Sky at energies > 100 GeV. Observations of astrophysical objects in the TeV band are sensitive probes of highly energetic processes occurring in these sources. The majority of the active galaxies detected at TeV energies are blazars, sources where we view the jet nearly along its axis. TeV and multiwavelength observations of blazars help us to better understand the mechanisms of ultrarelativistic jet production by supermassive black holes, and constrain models of particle acceleration in blazar jets. Galactic sources at TeV energies include supernova remnants, pulsar wind nebulae, and binary systems, and TeV emission is a key diagnostic of highly energetic particles in these objects. This report presents recent results from VERITAS on Galactic and extragalactic sources.


2009 ◽  
Vol 5 (H15) ◽  
pp. 808-808
Author(s):  
Emma de Oña-Wilhelmi

AbstractThe H.E.S.S. Galactic Plane Survey (GPS) has revealed a large number of Galactic Sources, including Pulsar Wind Nebulae (PWN), Supernova Remnants (SNRs), giant molecular clouds, star formation regions and compact binary systems, as well as a number of unidentified objects, or dark sources, for which no obvious counterparts at other wavelengths have yet been found. We will review the latest results from the GPS observations and discuss the most interesting cases.


1987 ◽  
Vol 125 ◽  
pp. 129-129
Author(s):  
J.L. Caswell ◽  
M.J. Kesteven ◽  
R.F. Haynes ◽  
D.K. Milne ◽  
M.M. Komesaroff ◽  
...  

Long after a supernova event, the stellar core (neutron star) may continue to excite an extended remnant of ejecta surrounding it, as in the case of the Crab nebula. In contrast, the more common shell supernova remnants (SNRs) appear unaffected by any embedded neutron star.


Author(s):  
Robert F O'Connell

First, we examine how spin is treated in special relativity and the necessity of introducing spin supplementary conditions (SSC) and how they are related to the choice of a center-of-mass of a spinning particle. Next, we discuss quantum electrodynamics and the Foldy-Wouthuysen transformation which we note is a position operator identical to the Pryce-Newton-Wigner position operator. The classical version of the operators are shown to be essential for the treatment of classical relativistic particles in general relativity, of special interest being the case of binary systems (black holes/neutron stars) which emit gravitational radiation.


1986 ◽  
Vol 64 (4) ◽  
pp. 474-478 ◽  
Author(s):  
Eric D. Feigelson

The evidence for jets emanating from neutron stars is reviewed. Isolated radio pulsars do not appear to produce collimated outflows. A few supernova remnants, notably the Crab nebula, exhibit jetlike protrusions at their outer boundaries. These are probably "blowouts" of the plasma in the remnant rather than true jets from a neutron star. However, several cases of degenerate stars in X-ray binary systems do make jets. SS433 has twin precessing jets moving outward at v ~ 0.26c, and Sco X-1 has radio lobes with v ~ 0.0001c. Cyg X-3 appears to eject synchrotron plasmoids at high velocities. Other X-ray binaries associated with variable radio sources are discussed; some are interesting candidates for collimated outflow. G109.1-1.0 is an X-ray binary in a supernova remnant that may have radio or X-ray jets. It is not clear in all these cases, however, that the compact object is a neutron star and not a black hole or white dwarf.A tentative conclusion is reached that isolated neutron stars do not produce jets, but degenerate stars in accreting binary systems can. This suggests that the presence of an accretion disk, rather than the characteristics of an isolated pulsar's dipole magnetosphere, is critical in making collimated outflows.


1969 ◽  
Vol 22 (5) ◽  
pp. 613 ◽  
Author(s):  
DK Milne

Brightness distributions and flux densities at 5000 MHz are presented for 17 nonthermal sources (possible supernova remnants) together with their spectra derived from these and other observations. For most sources a comparison has been made between the brightness distribution at 5000 MHz and that obtained with comparable resolution at 408 MHz with the Molonglo 1 mile Cross.


1971 ◽  
Vol 24 (4) ◽  
pp. 913 ◽  
Author(s):  
JB Whiteoak ◽  
FF Gardner

Maps are presented of the polarization and total intensity distributions over the supernova remnants 13S6A, MSH 15-56, ROW 103, and W44. They were obtained at 6 cm wavelength with a 4' arc resolution. It has not proved possible to interpret the polarization characteristics in terms of a simple expansion against the interstellar magneto ionic medium.


1968 ◽  
Vol 21 (5) ◽  
pp. 739 ◽  
Author(s):  
MJL Kesteven

The results of a survey with the 1 mile Molonglo cross-type radio telescope of nonthermal galactic sources are discussed in terms of supernova remnant theories. The contour maps obtained indicate that most sources are consistent with a portion of a shell of emission. The results suggest that a remnant's spectral index is independent of its age. A supernova remnant evolutionary path is also derived, and compared with the path predicted by the various theories.


Universe ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 24 ◽  
Author(s):  
Robert F. O’Connell

First, we examine how spin is treated in special relativity and the necessity of introducing spin supplementary conditions (SSC) and how they are related to the choice of a center-of-mass of a spinning particle. Next, we discuss quantum electrodynamics and the Foldy–Wouthuysen transformation which we note is a position operator identical to the Pryce–Newton–Wigner position operator. The classical version of the operators are shown to be essential for the treatment of classical relativistic particles in general relativity, of special interest being the case of binary systems (black holes/neutron stars) which emit gravitational radiation.


1983 ◽  
Vol 6 ◽  
pp. 531-533
Author(s):  
Geoffrey Burbidge

More than 20 years ago V. A. Ambartsumian proposed that much of the activity in galaxies was dominated and even generated by their nuclei. Subsequent observational work in radio, optical and x-ray frequencies has borne out his prophecy, and major interest has centered about the nature of the machine in the galactic nucleus. The major characteristic of this machine is that it releases energy rapidly and often spasmodically by processes which are not thermonuclear in origin.The original studies which led to the conclusion that nuclei were all important were observations of the powerful radio sources and Seyfert galaxies, and evidence for the ejection of gas from galaxies of many types. The realization that the synchrotron mechanism was the dominant radiation mechanism and the later studies of Compton radiation were fundamental in leading to the conclusion that large fluxes of relativistic particles must be generated in galactic nuclei.


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