Alien Registration- Coburn, John P. (Brownville, Piscataquis County)

https://digitalmaine.com/alien_docs/10034/thumbnail.jp

New direction for gamma-rays

The origin of energetic gamma-ray bursts is still unknown. But the detection of polarization of gamma-rays provides fresh insight into the mechanism driving these powerful explosions.Comment: Nature "News & Views", RE Coburn & Boggs (astro-ph/0305377

INTEGRAL observations of V0332+53 in outburst

We present the analysis of a 100ksec Integral(3-100kev) observation of the transient X-ray pulsar V0332+53 inoutburst. The source is pulsating at P=4.3751+/-0.0002s with a clear double pulse from 6 kev to 60 kev. The average flux was ~550mCrab between 20 kev and 60 kev. We modeled the broad band continuum from 5 kev to 100 kev with a power-law modified by an exponential cut off. We observe three cyclotron lines: the fundamental line at 24.9+/-0.1 kev, the first harmonic at 50.5+/-0.1 kev as well as the second harmonic at71.7+/-0.8 kev, thus confirming the discovery of the harmonic lines by Coburn et al. (2005) in RXTE data.Comment: 4 pages, 3 figures. Accepted for publication in A&A Letter

Nonsolar astronomy with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI)

The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is a NASA Small Explorer satellite designed to study hard x-ray and gamma-ray emission from solar flares. In addition, its high-resolution array of germanium detectors can see photons from high-energy sources throughout the Universe. Here we discuss the various algorithms necessary to extract spectra, lightcurves, and other information about cosmic gamma-ray bursts, pulsars, and other astrophysical phenomena using an unpointed, spinning array of detectors. We show some preliminary results and discuss our plans for future analyses. All RHESSI data are public, and scientists interested in participating should contact the principal author

Discovery of new quasi-periodic oscillations in the X-ray transient source V~0332+53

We report the discovery of a new quasi-period oscillation (QPO) at 0.22 Hz, centered on the source spin frequency of the high mass X-ray binary system V~0332+53 when the source was observed during its November 2004/March 2005 outburst by {\em RXTE}. Besides this new QPO, we also detected the known 0.05 Hz QPO. Both the 0.22 and 0.05 Hz QPOs stand out clearly at a mid-flux level of the outburst within January 15--19 2005, and later at an even lower flux level as the width of 0.22 Hz QPO drops. No evolution of the centroid frequency with the flux is seen in either QPO. The rms value below 10 keV is around 4--6% for both QPOs and decreases at higher energies. We discuss our results in the context of current QPO models.Comment: 5 figures, 12 pages. AASTex preprint style. (In 2005, ApJ Let., 629, L33

Study of the cyclotron feature in MXB 0656-072

We have monitored a type II outburst of the Be/X-ray binary MXB 0656−072 in a series of pointed RXTE observations during October through December 2003. The source spectrum shows a cyclotron resonance scattering feature at 32.8 +0.5 −0.4 keV, corresponding to a magnetic field strength of 3.67 +0.06 −0.04 × 10 12 G and is stable through the outburst and over the pulsar spin phase. The pulsar, with an average pulse period of 160.4 ± 0.4s,shows a spin-up of 0.45 s over the duration of the outburst. From optical data, the source distance is estimated to be 3.9 ± 0.1 kpc and this is used to estimate the X-ray luminosity and a theoretical prediction of the pulsar spin-up during the outburst