scholarly journals Radio study of the extended TeV source VER J1907+062

2019 ◽  
Vol 491 (4) ◽  
pp. 5732-5739
Author(s):  
L Duvidovich ◽  
A Petriella ◽  
E Giacani

ABSTRACT This paper aims to provide new insights on the origin of the TeV source VER J1907+062 through new high-quality radio observations. We used the Karl G. Jansky Very Large Array (VLA) to observe the whole extension of VER J1907+062 at 1.5 GHz with a mosaicking technique and the PSR J1907+0602 in a single pointing at 6 GHz. These data were used together with 12CO and atomic hydrogen observations obtained from public surveys to investigate the interstellar medium in the direction of VER J1907+062. The new radio observations do not show any evidence of a pulsar wind nebula (PWN) driven by the pulsars present in the field and no radio counterpart to the proposed X-ray PWN powered by PSR J1907+0602 is seen in the new VLA image at 6 GHz down to a noise level of 10 $\mu$Jy beam−1. Molecular clouds were discovered over the eastern, southern, and western borders of the radio shell of G40.5−0.5, suggesting an association with this supernova remnant. We explored several scenarios for the origin of VER J1907+062. We propose as the most probable scenario one in which the TeV emission is produced by two separated γ-ray sources located at different distances: one of leptonic origin and associated with a PWN powered by PSR J1907+0602 at ∼3.2 kpc and another of hadronic origin and produced by the interaction between G40.5−0.5 and the surrounding molecular gas at ∼8.7 kpc.

2014 ◽  
Vol 28 ◽  
pp. 1460172 ◽  
Author(s):  
LUCIA PAVAN ◽  
POL BORDAS ◽  
GERD PÜHLHOFER ◽  
MIROSLAV D. FILIPOVIC ◽  
AIN DE HORTA ◽  
...  

IGR J11014-6103 is a hard X-ray source discovered by INTEGRAL. Follow-up X-ray and radio observations revealed an elongated pulsar wind nebula formed by a neutron star escaping supersonically its parent supernova remnant SNR MSH 11-61A. The pulsar also emits highly collimated jets extending perpendicularly to the direction of motion. The jet has a continuous helical structure extending up to more than 10 parsecs. IGR J11014-6103 is a laboratory to study jet ejection in the wind of a pulsar and to constrain the core collapse supernova mechanism responsible for the observed pulsar kick velocity in excess of 1000 km/s.


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.


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).


2019 ◽  
Vol 491 (2) ◽  
pp. 3013-3021 ◽  
Author(s):  
B Guest ◽  
S Safi-Harb ◽  
A MacMaster ◽  
R Kothes ◽  
B Olmi ◽  
...  

ABSTRACT CTB 87 (G74.9+1.2) is an evolved supernova remnant (SNR) which hosts a peculiar pulsar wind nebula (PWN). The X-ray peak is offset from that observed in radio and lies towards the edge of the radio nebula. The putative pulsar, CXOU J201609.2+371110, was first resolved with Chandra and is surrounded by a compact and a more extended X-ray nebula. Here, we use a deep XMM–Newton observation to examine the morphology and evolutionary stage of the PWN and to search for thermal emission expected from a supernova shell or reverse shock interaction with supernova ejecta. We do not find evidence of thermal X-ray emission from the SNR and place an upper limit on the electron density of 0.05 cm−3 for a plasma temperature kT ∼ 0.8 keV. The morphology and spectral properties are consistent with a ∼20-kyr-old relic PWN expanding into a stellar wind-blown bubble. We also present the first X-ray spectral index map from the PWN and show that we can reproduce its morphology by means of 2D axisymmetric relativistic hydrodynamical simulations.


1989 ◽  
Vol 136 ◽  
pp. 157-158 ◽  
Author(s):  
J. G. Stacy ◽  
M. E. Bitran ◽  
T. M. Dame ◽  
P. Thaddeus

The discrepancy between observed and predicted γ-ray emission toward the Galactic Center is attributed to a unique population of wide-line molecular clouds. The most prominent objects of this class show evidence of rotation and a significant stellar population. The observed 12CO emission traces the gravitational field produced primarily by stars, not molecular gas.


1984 ◽  
Vol 283 ◽  
pp. 154 ◽  
Author(s):  
R. H. Becker ◽  
D. J. Helfand

2019 ◽  
Vol 623 ◽  
pp. A115 ◽  
Author(s):  
L. Duvidovich ◽  
E. Giacani ◽  
G. Castelletti ◽  
A. Petriella ◽  
L. Supán

Aims. The goal of this paper is to detect synchrotron emission from the relic electrons of the crushed pulsar wind nebula (PWN) HESS J1825−137 and to investigate the origin of the γ-ray emission from HESS J1826−130. Methods. The study of HESS J1825−137 was carried out on the basis of new radio observations centred at the position of PSR J1826−1334 performed with the Karl G. Jansky Very Large Array at 1.4 GHz in configurations B and C. To investigate the nature of HESS J1826−130, we reprocessed unpublished archival data obtained with XMM-Newton. Results. The new radio continuum image towards PSR J1826−1334 reveals a bright radio source, with the pulsar located in its centre, which suggests that this feature could be the radio counterpart of the compact component of the PWN detected at high energy. The new 1.4 GHz radio data do not reveal emission with an extension comparable with that observed in γ-rays for the HESS J1825−137 source. On the other hand, the XMM-Newton study of the region including PSR J1826−1256 reveals an elongated non-thermal X-ray emitting nebula with the pulsar located in the northern border and a tail towards the peak of the very high energy source. The spectrum is characterized by a power law with a photon index going from 1.6 around the pulsar to 2.7 in the borders of the nebula, a behaviour consistent with synchrotron cooling of electrons. From our X-ray analysis we propose that HESS J1826−130 is likely produced by the PWN powered by PSR J1826−1256 via the inverse Compton mechanism.


2012 ◽  
Vol 548 ◽  
pp. A46 ◽  
Author(s):  
◽  
A. Abramowski ◽  
F. Acero ◽  
F. Aharonian ◽  
A. G. Akhperjanian ◽  
...  
Keyword(s):  
X Ray ◽  

2013 ◽  
Vol 774 (1) ◽  
pp. 33 ◽  
Author(s):  
H. Matheson ◽  
S. Safi-Harb ◽  
R. Kothes
Keyword(s):  
X Ray ◽  

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