LISA Pathfinder test-mass charging during galactic cosmic-ray flux short-term variations
Abstract
Metal free-floating test masses aboard the future interferometers devoted to gravitational wave detection in space are charged by galactic and solar cosmic rays with energies $\gt $ > 100 MeV/n. This process represents one of the main sources of noise in the lowest frequency band ( $\lt $ < 10-3 Hz) of these experiments. We study here the charging of the LISA Pathfinder (LISA-PF) gold-platinum test masses due to galactic cosmic-ray (GCR) protons and helium nuclei with the Fluka Monte Carlo toolkit. Projections of the energy spectra of GCRs during the LISA-PF operations in 2015 are considered. This work was carried out on the basis of the solar activity level and solar polarity epoch expected for LISA-PF. The effects of GCR short-term variations are evaluated here for the first time. Classical Forbush decreases, GCR variations induced by the Sun rotation, and fluctuations in the LISA-PF frequency bandwidth are discussed.
- Publication:
-
Classical and Quantum Gravity
- Pub Date:
- February 2015
- DOI:
- 10.1088/0264-9381/32/3/035001
- Bibcode:
- 2015CQGra..32c5001G
- Keywords:
-
- gravitational radiation detectors;
- solar cycles;
- cosmic rays;
- interplanetary propagation;
- 95.55.Ym;
- 96.60.qd;
- 96.50.sb;
- 96.50.sh