On the hunt for mysterious gamma ray

50 years ago, so-called gamma-ray bursts were detected for the first time. Researchers have still not quite understood what exactly causes this phenomenon, which consists of an extremely energetic radiation bursts in distant galaxies. This mystery will now be explored by a new Swiss experiment, to be launched this coming autumn at the Paul Scherrer Institute (PSI).

Gamma-ray bursts, or GRBs, are the strongest emissions of energy in the entire universe. In just a few seconds, they release the same energy as the Sun during its entire lifetime. Although they were discovered almost 50 years ago, their origin is still unclear.

Wojciech Hajdas, a researcher at PSI’s Proton Irradiation Facility, wants to change that. To do so, Hajdas, a physicist, and his team created a small box, not much bigger than an inkjet printer. Inside: 1,600 thin plastic rods about the length of a kitchen knife. Using this tool, the researchers will investigate the bursts more accurately.

"The rods are made of a special plastic that has been enriched with certain chemicals,” Hajdas explains. “The light from the gamma radiation excites electrons inside them, which in turn emit visible light in a process known as scintillation."

Using scintillation to detect gamma rays is not new. But unlike previous experiments, the researchers are now trying to investigate the polarization of the radiation, which is a difficult property to measure.

The PSI team will work with China's second space station, Tiangong-2. Scheduled to be launched in the fall 2016, this facility should remain in space for several years and provide PSI’s gamma ray detector everything it needs: transportation into space, a measuring station once in orbit, and sufficient power.

Complete article on Deutchlandfunk's website:
http://www.deutschlandfunk.de/gammastrahlung-auf-der-jagd-nach-dem-phantom-der-astrophysik.676.de.html?dram:article_id=354575