A new way to discover pulsars

May 22, 2012 By David Reffkin
Simulation of a pulsar, showing magnetic field (blue lines) and high-energy jets at the poles (purple). Credit: NASA

(Phys.org) -- The Large Area Telescope (LAT), built by SLAC for the Fermi Gamma-ray Space Telescope, collects information on high-energy gamma rays from numerous sources in the sky. Among these are small, elusive objects called pulsars, which spin up to hundreds of times per second. Their name derives from the beams their magnetic fields produce as a result of this spin, which look like the pulsing beam of a lighthouse when, by chance, they happen to sweep across our field of view.

Pulsars are very interesting to scientists because they are special types of . Small (about 10 miles in diameter) and dense (one teaspoon weighs about a billion tons), they exhibit immense gravitational and not found on Earth.

The LAT has seen the gamma-ray signatures of more than 100 pulsars and is revolutionizing the study of these flashy objects in gamma rays, which are the most energetic form of light.

A team led by postdoctoral researcher Matthew Kerr of the Kavli Institute for and Cosmology (KIPAC), and Columbia University radio astronomer Fernando Camilo is reporting the use of new techniques for hunting pulsars. They and their colleagues have found a way to look for likely pulsar candidates by combining observations from the LAT and  the Parkes radio telescope in Australia. This approach combines the broad reach of an all-sky telescope (the LAT) with the deep sensitivity of a radio telescope, which can view only a tiny part of the sky at a time.

So far, the discovery of five more rapidly rotating, or “millisecond” pulsars, including one particularly intriguing object, prove that the technique is successful and likely to uncover many more pulsars  in our galaxy. One especially interesting object discovered with this technique seems to have a previously unknown waveform – a gamma-ray peak before and after each radio peak – an effect the team could not explain using standard models of pulsar geometry. This suggests that the radio part of the beam may originate at two distinct points above the object’s surface. This variation increases the mystery and allure of these fascinating astrophysical phenomena.

Explore further: A new approach in the search for extraterrestrial intelligence: targeting alien polluters

More information: Astrophysical Journal (ApJ, 2012, 748, 2)

Related Stories

Fermi telescope unveils a dozen new pulsars

Jan 06, 2009

(PhysOrg.com) -- NASA's Fermi Gamma-ray Space Telescope has discovered 12 new gamma-ray-only pulsars and has detected gamma-ray pulses from 18 others. The finds are transforming our understanding of how these ...

Recommended for you

Satellite galaxies put astronomers in a spin

5 hours ago

An international team of researchers, led by astronomers at the Observatoire Astronomique de Strasbourg (CNRS/Université de Strasbourg), has studied 380 galaxies and shown that their small satellite galaxies almost always ...

Video: The diversity of habitable zones and the planets

6 hours ago

The field of exoplanets has rapidly expanded from the exclusivity of exoplanet detection to include exoplanet characterization. A key step towards this characterization is the determination of which planets occupy the Habitable ...

Ultra-deep astrophoto of the Antenna Galaxies

6 hours ago

You might think the image above of the famous Antenna Galaxies was taken by a large ground-based or even a space telescope. Think again. Amateur astronomer Rolf Wahl Olsen from New Zealand compiled a total ...

The most precise measurement of an alien world's size

7 hours ago

Thanks to NASA's Kepler and Spitzer Space Telescopes, scientists have made the most precise measurement ever of the radius of a planet outside our solar system. The size of the exoplanet, dubbed Kepler-93b, ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Husky
5 / 5 (2) May 22, 2012
maybe the object has an unusual large precession (e.g. when the neutron star formed while merging with another star), if it spins hundreds of times per second and we only see parts of the beam heading in our direction it would appear to originate at different locations at the surface, most interestingly i read that When an object is not perfectly solid, internal vortices will tend to damp torque-free precession, and the rotation axis will align itself with one of the inertia axes of the body, so, watching this over time we could see how the peaks evolve and infer the "solidness" of the star?