Soft X-Ray Emission from the Radio Pulsar PSR 0656+14
Abstract
A radio source with a flux density of a few mJy was found in the error region of the soft X-ray source E0656 + 14, and identified as the radio pulsar PSR 0656 + 14. The radio source has a steep, nonthermal spectrum and a high degree of linear (62 percent) and circular (19 percent) polarization. The X-ray spectrum of the pulsar is among the softest sources observed with the Einstein Observatory. The X-ray data taken with the Einstein imaging proportional counter (IPC) permit a range of blackbody temperatures of 3-6 x 10 to the 5th K, and an equivalent column density of hydrogen smaller than 4 x 10 to the 20th/sq cm. If the assumption is made that the X-ray flux is thermal radiation from surface of the neutron star, then the pulsar must be at a distance smaller than 550 pc, consistent with the low dispersion measure of PSR 0656 + 14. The X-ray timing data suggest that the X-ray emission is modulated at the pulsar's 0.385-s spin period with an amplitude of 18 percent + or - 6 percent, and that there is a 0.0002 probability that this is spurious. It was noted that PSR 0656 + 14 is close to the geometric center of a 20-deg diameter soft X-ray emitting ring called the Gemini-Monoceros enhancement. The close distance of the pulsar, together with its relatively young age of 1.1 x 10 to the 5th yr, makes it possible that the ring is a supernova remnant from the explosion of the pulsar's progenitor. A radio source extending over a region 1.2 to 3.3 arcmin south of the pulsar is a candidate for association with the pulsar.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1989
- DOI:
- 10.1086/167918
- Bibcode:
- 1989ApJ...345..451C
- Keywords:
-
- Emission Spectra;
- Pulsars;
- Supernova Remnants;
- X Ray Sources;
- Brightness Distribution;
- Heao 2;
- Neutron Stars;
- Power Spectra;
- Radio Emission;
- Very Large Array (Vla);
- Astrophysics;
- NEBULAE: SUPERNOVA REMNANTS;
- POLARIZATION;
- PULSARS;
- STARS: INDIVIDUAL ALPHANUMERIC: PSR 0656;
- 14;
- STARS: NEUTRON;
- STARS: RADIO RADIATION;
- X-RAYS: SOURCES