Research Objectives:
BESS-Polar is a joint project of Japanese and US scientists to search for antimatter in the cosmic radiation and measure energy and intensity of less exotic components of the cosmic radiation. The antimatter search is of great interest in that it may provide answers to questions of cosmological significance dating from the creation of the Universe:
1. Is the Universe "baryon symmetric"? That is, does it contain equal amounts of matter and antimatter? Might there exist antimatter galaxies? Discovery of a single antihelium would answer this question.
2. Is there an excess of low energy antiprotons beyond that expected from "standard" processes? If so, BESS measurements may provide evidence for the existence of primordial black holes or dark matter.
The BESS-Polar instrument is a large superconducting magnet augmented with a variety of detectors for tracking charged particles and determining their momentum, velocity and identity. The payload has the largest geometry factor of any balloon-borne magnet spectrometer currently flying and is ideally suited for identifying antiprotons and the nuclei of antihelium.
The long-duration flight of BESS-Polar is expected to provide data of unprecedented sensitivity in searching for antihelium and low energy antiprotons. It will also measure proton and helium spectra and separate light isotopes in galactic cosmic rays.
