Development of a micro-satellite TSUBAME for X-ray polarimetry of GRBs

TL;DR

TSUBAME is a micro-satellite developed by Tokyo Tech students to measure X-ray polarization of GRBs, aiming to understand their central engines, with recent progress reported after launch and system integration.

Contribution

This paper details the development, system integration, and post-launch progress of TSUBAME, a novel micro-satellite for GRB X-ray polarimetry.

Findings

Successful satellite assembly and integration

Launch and orbit insertion in 2014

Operational status of X-ray sensors as of 2015

Abstract

TSUBAME is a micro-satellite that the students of Tokyo Institute of Technology took the lead to develop for measuring hard X-ray polarization of Gamma-Ray Bursts(GRBs) in order to reveal the nature of the central engine of GRBs. TSUBAME has two instruments: Wide-field Burst Monitor (WBM) and Hard X-ray Compton Polarimeter (HXCP). We aim to start observing with HXCP in 15 seconds by pointing the spacecraft using Control Moment Gyro. In August 2014, we assembled TSUBAME and performed an integration test during ~2 weeks.TSUBAME by communication tests with Cute-1.7+APDII in orbit. On Nov 6 2014, TSUBAME was launched from Russia and it was put into Sun-synchronous orbit at 500 km above the ground. However, serious trouble occurred to the ham radio equipment. Therefore we could not start up the X-ray sensors until Feb 10 2015. In this paper, we report the system of TSUBAME and the progress after the launch.