Emissions from the central pulsar are very strong

Sep 23, 2011 10:40 GMT  ·  By
The GRAPE balloon payload shown during a power-up compatibility test on September 13 at the Columbia Scientific Balloon Facility in Ft. Sumner, New Mexico
   The GRAPE balloon payload shown during a power-up compatibility test on September 13 at the Columbia Scientific Balloon Facility in Ft. Sumner, New Mexico

Scientists with the University of New Hampshire (UNH) began a new scientific investigation on Sunday, September 18, when they sought to launch a science balloon up into Earth's stratosphere. The launch was to take place from a NASA launch facility in Fort Summer, New Mexico.

The science balloon is capable of reaching an operating altitude of about 130,000 feet (39,624 meters). This far up in the sky, the instruments making up its science payload suffer very few interferences from molecules in the planet's atmosphere.

According to the research team, the goal of this investigation is to discover the nature of gamma-ray emissions coming from the pulsar at the core of the Crab Nebula. The supernova remnant is located relatively close, at a distance of only 6,500 light-years away.

UNH experts have until the end of this week to launch their mission. The main instrument on the balloon is the Gamma Ray Polarimeter Experiment (GRAPE), which was developed by the UNH Institute for the Study of Earth, Oceans, and Space (EOS) Space Science Center.

GRAPE is especially focused on studying the polarization of gamma-rays from celestial sources. What this means is that it looks for preferred directions of spin in the photons making up these emissions.

Physicists believe that the polarization of a light beam carries significant information about how that beam was generated in the first place. Knowing this could then reveal more insight into the nature of the celestial body that released the light.

In objects such as the Crab Nebula pulsar, gamma-rays are massive ejections of high-energy particles, which occur when strong magnetic fields around the object accelerate elementary particles to speeds nearing that of light, SpaceRef reports.

“We think that an accelerated beam of particles is the source of the high-energy radiation from the Crab Pulsar, but the structure of that beam and the mechanism by which the radiation is generated is not entirely clear,” researcher Mark McConnell explains.

The expert – who is the lead scientist on the mission – holds an appointment as an SSC professor and the chair of the UNH Department of Physics. He explains that learning how pulsars act could have implications for the way our magnetosphere functions.

“To study the gamma-ray burst phenomena we need much more time because they occur randomly in the sky at a rate of about once per day and last at most a couple of minutes. So a long flight will be required to measure a number of bursts,” he concludes.