In search for superheavy nuclei in space


Flerov Laboratory of Nuclear Reactions invites to a seminar scheduled for today, 6 April, at 11:00 AM, at which FIAN doctoral candidate, Candidate of Physics and Mathematics Tan Naing Soe will make a report “Methods for search and investigation of heavy and superheavy nucleus tracks of galactic cosmic rays based on results of olivine measurements from meteorites”.

On the left: sample of Seymchan meteorite. On the right: one field of microscope vision with 40x magnification

The seminar wil ltake place offline in the FLNR Conference Hall and online on the Webex platform.

A few words from the abstract:

The aim of the OLIMPIYA experiment is to search for and identify traces of heavy and superheavy nuclei of galactic cosmic rays (GCR) in olivine crystals from stony-iron meteorites serving as nuclear track detectors. Participants of the OLIMPIYA experiment collect data about the content of a heavy component of space irradiation (nuclei with Z>55), assess the values of their flows, and build up statistically supported charge spectrum in this charge field. Being irradiated in space, olivine crystals ((Mg0.8,Fe0.2)2SiO4) as parts of pallasite meteorites accumulate traces of GCR nuclei heavier than ferrum. The uniqueness of these natural detectors is their long-term irradiation: flows of superheavy nuclei as parts of cosmic rays are tiny. So to get statistically significant result, it is necessary either to have a large-scale facility in space or to ensure a very long exposure time. The age of pallasites used in the work (Marjalahti and Eagle Station, provided to FIAN for the investigation at the Laboratory of Nuclear Reactions) is estimated from 30 to 175 million years. To date, the OLIMPIYA project has found and identified about 26,000 thousand nuclei with the charge of more than 50.

The speaker will report on the method of olivine study, discovered peculiarities (unusual traces, annealing, fragmentation), charge spectrum obtained, etc.

  Download full abstract (in Russian)