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West Virginia University physics Professor Maura McLaughlin contributed to a discovery unveiled Jan. 5 that promises a bounty of science yields.
The identification of 17 new millisecond pulsars, announced at a meeting of the American Astronomical Society, could bring advances in astrophysics ranging from the potential direct detection of gravitational waves to gamma-ray emission mechanisms, stellar evolution and millisecond pulsar formation.

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Millisecond pulsars
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Radio astronomers have uncovered 17 millisecond pulsars in our galaxy by studying unknown high-energy sources detected by NASA's Fermi Gamma-ray Space Telescope. The astronomers made the discovery in less than three months. Such a jump in the pace of locating these hard-to-find objects holds the promise of using them as a kind of "galactic GPS" to detect gravitational waves passing near Earth.
A pulsar is the rapidly spinning and highly magnetised core left behind when a massive star explodes. Because only rotation powers their intense gamma-ray, radio and particle emissions, pulsars gradually slow as they age. But the oldest pulsars spin hundreds of times per second -- faster than a kitchen blender. These millisecond pulsars have been spun up and rejuvenated by accreting matter from a companion star.

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Scientists at the Naval Research Laboratory Space Science Division and a team of international researchers have positively identified cosmic sources of gamma-ray emissions through the discovery of 16 pulsating neutron stars.
Using the Large Area Telescope (LAT), the primary instrument on NASA's Fermi Gamma-ray Space Telescope satellite, the discoveries were made by conducting blind frequency searches on the sparse photon data provided by the LAT. The photons had energies between 20 Mega-electron-volts (MeVs) and 300 Giga-electron-volts (GeVs)- tens of millions to hundreds of billions of times more energetic than the photons we see with the human eye.
A second study, published at the same time, announced the detection of gamma-ray pulsations from eight Galactic millisecond pulsars (MSPs). Millisecond pulsars spin hundreds of times per second, but have magnetic fields 10,000 times lower than normal pulsars. These discoveries confirm that they, too, can produce powerful gamma-ray emissions.
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Image from the Fermi Gamma-ray Space Telescope displays newly found pulsars (circled in yellow) and millisecond pulsars (Circled in magenta).
Source: NASA/DoE/Fermi LAT Collaboration


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Neutron stars
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In a new research, an Indian scientist has determined that the pattern of x-rays generated by neutron stars may reveal their true size.
According to a report by ABC News, Dr Sudip Bhattacharyya of the Tata Institute of Fundamental Research in India led the research.


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Astronomers get neutron star's measure
The pattern of x-rays generated by neutron stars may reveal their true size, says an international team of astrophysicists.
Research, led by Dr Sudip Bhattacharyya of the Tata Institute of Fundamental Research in India, has revealed an unsuspected property of x-ray bursts given off by the stars.
The research has been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.

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Swirling gas sets pulsar spinning in supercomputer simulation.

This visualisation of a simulated supernova is helping to reveal why pulsars spin so fast. Pulsars are neutron stars that emit beams of electromagnetic radiation as they whirl around many times per second - a rate that astrophysicists had struggled to explain. Pulsars are thought to form in core-collapse supernovae, the explosive deaths of stars at least eight times the mass of the Sun, in which the iron core collapses in on itself.
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Lovell telescope helps scientists solve gamma-ray mystery
Scientists from the University of Manchester have worked with an international team of astronomers using NASA's Fermi Gamma-ray Space Telescope to get a new look at the spinning cosmic lighthouses known as pulsars.
In two studies published in Science Express, the team has analysed gamma-rays from two dozen pulsars - including eight of the most rapidly rotating pulsars.
These detections were only possible thanks to the contributions of radio telescopes like the Lovell Telescope at The Jodrell Bank Centre for Astrophysics, which is owned and operated by The University of Manchester.

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Millisecond Pulsars
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Astronomers at the University of California, Santa Cruz, have developed a new technique to determine the ages of millisecond pulsars, the fastest-spinning stars in the universe.
The standard method for estimating pulsar ages is known to yield unreliable results, especially for the fast-spinning millisecond pulsars, said Bülent Kiziltan, a graduate student in astronomy and astrophysics at UCSC.

"An accurate determination of pulsar ages is of fundamental importance, because it has ramifications for understanding the formation and evolution of pulsars, the physics of neutron stars, and other areas" - Bülent Kiziltan.

Kiziltan has been working with Stephen Thorsett, professor of astronomy and astrophysics at UCSC, to study the evolution of millisecond pulsars. He will present their new findings at the American Astronomical Society meeting in Pasadena on Monday, June 8.

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Three new pulsars
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Title: Discovery of three new pulsars in a 610 MHz pulsar survey with the GMRT
Authors: B. C. Joshi (1), M. A. McLaughlin (2), A. G. Lyne (3), D. A. Ludovici (2), N. A. Pawar (1), A. J. Faulkner (3 and 4), D. R. Lorimer (2), M. Kramer (3 and 5), M. L. Davies (4) ((1) National Centre for Radio Astrophysics, Pune, India, (2) Department of Physics, West Virginia University, Morgantown, USA, (3) University of Manchester, Jodrell Bank Centre for Astrophysics, Manchester, UK, (4) Astrophysics Group, University of Cambridge, Cambridge, UK, (5) MPI fuer Radioastronomie, Bonn, Germany)

We report on the discovery of three new pulsars in the first blind survey of the north Galactic plane (45 degrees < l < 135 degrees; |b| < 1 degrees with the Giant Meterwave Radio telescope (GMRT) at an intermediate frequency of 610 MHz. The survey covered 106 square degrees with a sensitivity of roughly 1 mJy to long-period pulsars (pulsars with period longer than 1 s). The three new pulsars have periods of 318, 933, and 1056 ms. Their timing parameters and flux densities, obtained in follow up observations with the Lovell Telescope at Jodrell Bank and the GMRT, are presented. We also report on pulse nulling behaviour in one of the newly discovered pulsars, PSR J2208+5500.

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