Measurement of iron cosmic-ray primaries below 10 GeV/n by use of the geomagnetic effect with CALET

Date

2023-07-25

Department

Program

Citation of Original Publication

Ichimura, M., et al. "Measurement of iron cosmic-ray primaries below 10 GeV/n by use of the geomagnetic effect with CALET." Paper presented at 38th International Cosmic Ray Conference (ICRC2023) 26 July - 3 August, 2023 instrument Nagoya, Japan. https://doi.org/10.22323/1.444.0057.

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.||Public Domain

Subjects

Abstract

The CALET Calorimeter on the International Space Station(ISS) has previously measured the flux and spectrum of iron cosmic-ray nuclei above 10 GeV/n. In order to extend the measurement to the region below 10 GeV/n, we carry out an analysis to utilize the geomagnetic effect. Cutoff rigidities of cosmic-ray nuclei are calculated for all directions for each observation point in the ISS orbit. The integral spectrum of observed rigidities is then obtained by counting the number of iron nuclei in each bin of cutoff rigidity. The absolute flux and differential spectrum are then calculated by taking the detection efficiencies into account. Here we present the details of the analysis procedure and the iron spectrum below 10 GeV/n.