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Post Info TOPIC: PSR B1509-58
Blobrana


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RE: PSR B1509-58
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Title: AGILE and Fermi Observations of the Soft Gamma-Ray Pulsar B1509-58
Authors: Maura Pilia, Alberto Pellizzoni, for the AGILE Team

We present the results of 2.5 years of AGILE observations of PSR B1509-58 and of the same interval of Fermi observations. The modulation significance of AGILE light curve above 30 MeV is at a 5 sigma confidence level and the light curve shows a broad asymmetric first peak reaching its maximum 0.39 ±0.02 cycles after the radio peak plus a second peak at 0.94 ±0.03. The gamma-ray spectral energy distribution of pulsed flux is well described by a power-law (photon index \alpha=1.87 ±0.09) with a remarkable cutoff at below 100 MeV, representing the softest spectrum observed among gamma-ray pulsars so far. The unusual soft break in the spectrum of PSR B1509-58 has been interpreted in the framework of polar cap models as a signature of the exotic photon splitting process in the strong magnetic field of this pulsar. In the case of an outer-gap scenario, or the two pole caustic model, better constraints on the geometry of the emission would be needed from the radio band in order to establish whether the conditions required by the models to reproduce AGILE light curves and spectra match the polarisation measurements.

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Blobrana


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Title: Long-Term X-ray Monitoring of the Young Pulsar PSR B1509-58
Authors: Margaret A. Livingstone, Victoria M. Kaspi

It has long been thought that the pulsed X-ray properties of rotation-powered pulsars are stable on long time scales. However, long-term, systematic studies of individual sources have been lacking. Furthermore, dramatic X-ray variability has now been observed from two pulsars having inferred sub-critical dipole magnetic fields. Here we present an analysis of the long-term pulsed X-ray properties of the young, energetic pulsar PSR B1509-58 using data from the Rossi X-ray Timing Explorer. We measured the 2-50 keV pulsed flux for 14.7 yr of X-ray observations and found that it is consistent with being constant on all relevant time scales, and place a 3 sigma upper limit on day-to-week variability of <28%. In addition, we searched for magnetar-like X-ray bursts in all observations and found none, which we use to constrain the measurable burst rate to less than one per 750 ks of observations. We also searched for variability in the pulse profile and found that it is consistent with being stable on time scales of days to decades. This supports the hypothesis that X-ray properties of rotation-powered X-ray pulsars can be stable on decade-long time scales. In addition, we extend the existing timing solution by 7.1 yr to a total of 28.4 yr and report updated values of the braking index, n=2.832±0.003 and the second braking index, m=17.6±1.9.

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Blobrana


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PSR B1509-58 is a pulsar approximately 17,000 light-years away in the constellation  of Circinus  discovered by the Einstein X-Ray Observatory in 1982. It is approximately 1700 years old and sits in a nebula that spans 150 light years.
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Blobrana


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Pulsar B1509-58
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It looks like a hand of a God reaching out into the cosmos, but scientists say it's something just as incredible: electromagnetic energy pumped out by a neutron star.
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Blobrana


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A spinning star resembling a giant cosmic hand has been captured in images taken by a Nasa observatory orbiting miles above the Earth's surface.
The Chandra X-ray Observatory pictured the star, which measures 12 miles across, about 17,000 light years from Earth.

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Blobrana


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A small, dense object only twelve miles in diameter is responsible for a beautiful X-ray nebula that spans 150 light years.
At the center of a new image made by NASA's Chandra X-ray Observatory is a very young and powerful pulsar, known as PSR B1509-58, or B1509 for short. The pulsar is a rapidly spinning neutron star which is spewing energy out into the space around it to create complex and intriguing structures, including one that resembles a large cosmic hand.
In the new image, the lowest energy X-rays that Chandra detects are red, the medium range is green, and the most energetic ones are colored blue. Astronomers think that B1509 is about 1,700 years old and is located about 17,000 light years away.

Position(J2000):      RA 15h 13m 55.52s, Dec -59° 08' 08.8"

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