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RE: Pulsars
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Baby pulsars spawn universe's most energetic particles

Baby pulsars may unleash torrents of the highest energy particles known, explaining the provenance of the ultra-high-energy cosmic rays that hit Earth. Charged particles with energies of at least 1019 electronvolts slam into our atmosphere from time to time - since 2008, 5000 have been detected by the Auger observatory in Argentina.
Their source has been a mystery. Pulsars - ultradense stars formed during supernova blasts - are one candidate, but it has not been clear if the particles they shed could make it through the dense shroud of stellar shrapnel that surrounds them.
Now Ke Fang and colleagues at the University of Chicago have modelled these particles and found that they can escape within the first year of a pulsar's life.

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Globular Cluster Pulsars
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Title: The Timing of Nine Globular Cluster Pulsars
Authors: Ryan S. Lynch, Paulo C. C. Freire, Scott M. Ransom, Bryan A. Jacoby

We have used the Robert C. Byrd Green Bank Telescope to time nine previously known pulsars without published timing solutions in the globular clusters M62, NGC 6544, and NGC 6624. We have full timing solutions that measure the spin, astrometric, and (where applicable) binary parameters for six of these pulsars. The remaining three pulsars (reported here for the first time) were not detected enough to establish solutions. We also report our timing solutions for five pulsars with previously published solutions, and find good agreement with past authors, except for PSR J1701-3006B in M62. Gas in this system is probably responsible for the discrepancy in orbital parameters, and we have been able to measure a change in the orbital period over the course of our observations. Among the pulsars with new solutions we find several binary pulsars with very low mass companions (members of the so-called "black widow" class) and we are able to place constraints on the mass-to-light ratio in two clusters. We confirm that one of the pulsars in NGC 6624 is indeed a member of the rare class of non-recycled pulsars found in globular clusters. We also have measured the orbital precession and Shapiro delay for a relativistic binary in NGC 6544. If we assume that the orbital precession can be described entirely by general relativity, which is likely, we are able to measure the total system mass (2.57190(73) solar masses) and companion mass (1.2064(20) solar masses), from which we derive the orbital inclination [sin(i) = 0.9956(14)] and the pulsar mass (1.3655(21) solar masses), the most precise such measurement ever obtained for a millisecond pulsar. The companion is the most massive known around a fully recycled pulsar.

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Discovery of the 1000th Pulsar

13 November 1998

An international team of researchers using a giant radio telescope in Australia, equipped with a new "multibeam" receiver system, has just discovered the 1000th pulsar to be found within our Galaxy since the first few were discovered in Cambridge in 1967.
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NASA's Fermi to Reveal New Findings About Pulsars
2 p.m. EDT, Thursday, Nov. 3

NASA will hold a media teleconference to discuss new discoveries about pulsars by the Fermi Gamma-ray Space Telescope.
A pulsar is the closest thing to a black hole astronomers can observe directly. Pulsars are capable of crushing half a million times more mass than Earth into a sphere no larger than a city. Some of these objects spin tens of thousands of revolutions per minute, faster than the blades of a kitchen blender.

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Millisecond pulsars
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Scott Ransom wins the American Astronomical Society's 2010 Helen B. Warner Prize and talks about his most recent research on pulsars.


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B1957+20
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Black widow pulsar is fattest collapsed star yet

A cannibalistic collapsed star is growing so fat from the partner it is slowly devouring that it is likely to be the most massive neutron star yet measured. The observation suggests that neutron stars can grow much bigger than previously thought before collapsing to become a black hole.
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Astronomers find cause of "dicky tickers"

In today's issue of Science, CSIRO astronomer George Hobbs and colleagues in the UK, Germany and Canada report that they have taken a big step towards solving a 30-year-old puzzle: why the "cosmic clocks" called pulsars aren't perfect.
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Cosmic clocks hold the key to the secrets of the Universe

An international team of scientists have developed a promising new technique which could turn pulsars - superb natural cosmic clocks - into even more accurate time-keepers.
This important advance, led by scientists at The University of Manchester and appearing today (June 24th) in the journal Science Express, could improve the search for gravitational waves and help studies into the origins of the universe.
The direct discovery of gravitational waves, which pass over cosmic clocks and cause them to change, could allow scientists to study violent events such as the merging of super-massive black holes and help understand the universe shortly after its formation in the Big Bang.
The scientists made their breakthrough using decades-long observations from the 76-m Lovell radio telescope at The University of Manchester's Jodrell Bank Observatory to track the radio signals of extreme stars known as pulsars.

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A ground breaking link up of three telescopes is to provide us with new insight into the Universes most extreme stars.

An International team of astronomers used the new European LOFAR telescope combined with two of the world's largest radio telescopes, the Lovell telescope at Jodrell Bank-part of The University of Manchester and the Effelsberg telescope in Germany, to understand more about the enigmatic radio emitting stars called Pulsars.
The unique combination of telescopes allowed the team to simultaneously observe the radio waves from six different pulsars across wavelengths from only 3.4 centimetres up to 7 metres - a factor of 200 difference and the highest achieved anywhere in the world.
The different wavelengths of radio light can be compared to the different colours perceived by the human eye and provide an unprecedented view of how radio pulsars shine.

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Pulsars in many octaves

A unique combination of telescopes allowed astronomers to simultaneously observe the radio wavelength light from six different pulsars across wavelengths from only 3.5 centimetres up to 7 metres - a difference-factor of 200, providing an unprecedented view of how radio pulsars shine. For this world record in wavelength coverage, the international team, including scientists from the Max Planck Institute for Radio Astronomy, used the new European LOFAR telescope, in combination with two of the world's largest radio telescopes, the 100 metre Effelsberg telescope in Germany and the 76 metre Lovell telescope in the United Kingdom.
Pulsars are rapidly rotating neutron stars, which measure only about 20 kilometres across and yet are more massive than the Sun. They produce beams of radio light from their magnetic poles, which are observable over a wide range of wavelengths. For the last 40 years astronomers have been studying pulsars and have been getting closer to understanding the mechanism that generates these intense beams. They hypothesise that the emission seen at the different wavelengths emerges from different heights above the highly magnetized pulsar surface. Emission seen at a particular radio wavelength therefore provides a slice through the pulsar's surrounding "magnetosphere" (magnetised atmosphere).

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