December 17, 2013

Image Caption: An artist's rendering of the Swift spacecraft with a gamma-ray burst going off in the background. Credit: Spectrum Astro and NASA E/PO, Sonoma State University, Aurore Simonnet

redOrbit Staff & Wire Reports Your Universe Online

By analyzing data collected by NASAs Swift robotic spacecraft, astronomers from the University of Leicester have reportedly discovered the location of nearly 100,000 previously unknown cosmic X-ray sources.

The research team studied eight years worth of observations collected during the Swift Gamma-Ray Burst Mission to compile a catalog of major celestial X-ray sources a list that includes more than 150,000 high-energy stars and galaxies and appears in the latest edition of The Astrophysical Journal.

In addition to providing the positions of almost a hundred thousand previously unknown X-ray sources, the team have also analyzed the X-ray variability and X-ray colors of the sources in order to help to understand the origin of their emission, and to help in the classification of rare and exotic objects, the university said in a statement Monday. All of the data, including light curves and spectra are available online.

The Swift satellite was originally launched back in November 2004, and since then it has been studying the immensely powerful stellar explosions, which date back to the earliest days of the universe. The study authors have called it one of the most productive observatories, ever since its launch.

Over the past eight years, Swift has helped revolutionize gamma ray burst (GRB) research thanks largely to its powerful X-ray telescope, which was built at the UK university. In addition to finding the afterglows of these gamma-ray bursts, the telescope can also detect several other types of x-ray sources located within its field of view.

In order to be able to respond quickly to the rapidly fading GRBs, Swift is uniquely agile and autonomous, able to point within a minute or so at a new target, the university said. Because of its science remit and this unusual ability, the Swift XRT has observed a much larger fraction of the sky than the larger European and US X-ray observatories. For this reason it has found a vast number of extra sources in spite of its much lower cost.

Most of the newly discovered X-ray sources are expected to signal the presence of super-massive black holes in the centers of large galaxies many millions of light-years from earth, but the catalogue also contains transient objects (short-lived bursts of X-ray emission) which may come from stellar flares or supernovae, the university said.

Read the original here:

Swift Data Reveals 100K New Cosmic X-Ray Source Locations