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Title: Discovery of a Synchrotron Bubble Associated with PSR J1015–5719

Abstract

We report the discovery of a synchrotron nebula, G283.1−0.59, associated with PSR J1015−5719. Radio observations using the Molonglo Observatory Synthesis Telescope and the Australia Telescope Compact Array at 36, 16, 6, and 3 cm reveal a complex morphology. The pulsar is embedded in the “head” of the nebula with fan-shaped diffuse emission. This is connected to a circular bubble of 20″ radius and a collimated tail extending over 1′. Polarization measurements show a highly ordered magnetic field in the nebula. It wraps around the edge of the head and shows an azimuthal configuration near the pulsar, then switches direction quasi-periodically near the bubble and in the tail. Together with the flat radio spectrum observed, we suggest that this system is most plausibly a pulsar wind nebula (PWN), with the head as a bow shock that has a low Mach number and the bubble as a shell expanding in a dense environment. The bubble could act as a magnetic bottle trapping the relativistic particles. A comparison with other bow-shock PWNe with higher Mach numbers shows similar structure and B -field geometry, implying that pulsar velocity may not be the most critical factor in determining the properties of these systems. We alsomore » derive analytic expressions for the projected standoff distance and shape of an inclined bow shock. It is found that the projected distance is always larger than the true distance in three dimensions. On the other hand, the projected shape is not sensitive to the inclination after rescaling with the projected standoff distance.« less

Authors:
 [1];  [2];  [3];  [4]
  1. Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong)
  2. Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)
  3. Sydney Institute for Astronomy (SIfA), School of Physics, The University of Sydney, NSW 2006 (Australia)
  4. CSIRO Astronomy and Space Science, P.O. Box 76, Epping NSW 1710 (Australia)
Publication Date:
OSTI Identifier:
22663481
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 842; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BUBBLES; EMISSION; INCLINATION; MACH NUMBER; MAGNETIC FIELDS; NEBULAE; NEUTRONS; PERIODICITY; POLARIZATION; PULSARS; RELATIVISTIC RANGE; SHOCK WAVES; SPECTRA; STARS; STELLAR WINDS; SWITCHES; SYNCHROTRONS; TELESCOPES; TRAPPING

Citation Formats

Ng, C.-Y., Bandiera, R., Hunstead, R. W., and Johnston, S., E-mail: ncy@bohr.physics.hku.hk. Discovery of a Synchrotron Bubble Associated with PSR J1015–5719. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA762E.
Ng, C.-Y., Bandiera, R., Hunstead, R. W., & Johnston, S., E-mail: ncy@bohr.physics.hku.hk. Discovery of a Synchrotron Bubble Associated with PSR J1015–5719. United States. doi:10.3847/1538-4357/AA762E.
Ng, C.-Y., Bandiera, R., Hunstead, R. W., and Johnston, S., E-mail: ncy@bohr.physics.hku.hk. Tue . "Discovery of a Synchrotron Bubble Associated with PSR J1015–5719". United States. doi:10.3847/1538-4357/AA762E.
@article{osti_22663481,
title = {Discovery of a Synchrotron Bubble Associated with PSR J1015–5719},
author = {Ng, C.-Y. and Bandiera, R. and Hunstead, R. W. and Johnston, S., E-mail: ncy@bohr.physics.hku.hk},
abstractNote = {We report the discovery of a synchrotron nebula, G283.1−0.59, associated with PSR J1015−5719. Radio observations using the Molonglo Observatory Synthesis Telescope and the Australia Telescope Compact Array at 36, 16, 6, and 3 cm reveal a complex morphology. The pulsar is embedded in the “head” of the nebula with fan-shaped diffuse emission. This is connected to a circular bubble of 20″ radius and a collimated tail extending over 1′. Polarization measurements show a highly ordered magnetic field in the nebula. It wraps around the edge of the head and shows an azimuthal configuration near the pulsar, then switches direction quasi-periodically near the bubble and in the tail. Together with the flat radio spectrum observed, we suggest that this system is most plausibly a pulsar wind nebula (PWN), with the head as a bow shock that has a low Mach number and the bubble as a shell expanding in a dense environment. The bubble could act as a magnetic bottle trapping the relativistic particles. A comparison with other bow-shock PWNe with higher Mach numbers shows similar structure and B -field geometry, implying that pulsar velocity may not be the most critical factor in determining the properties of these systems. We also derive analytic expressions for the projected standoff distance and shape of an inclined bow shock. It is found that the projected distance is always larger than the true distance in three dimensions. On the other hand, the projected shape is not sensitive to the inclination after rescaling with the projected standoff distance.},
doi = {10.3847/1538-4357/AA762E},
journal = {Astrophysical Journal},
number = 2,
volume = 842,
place = {United States},
year = {Tue Jun 20 00:00:00 EDT 2017},
month = {Tue Jun 20 00:00:00 EDT 2017}
}
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