The First MAXI/SSC Catalog of X-ray Sources in 0.7--7.0~keV

TL;DR

This paper presents the first MAXI/SSC X-ray source catalog based on 45 months of data, identifying 170 sources in the 0.7--7.0 keV range, with many sources matched to known astronomical objects and some showing flux variability over 20 years.

Contribution

It provides the inaugural catalog of X-ray sources from MAXI/SSC, expanding the understanding of X-ray sources in the 0.7--7.0 keV band with detailed source identification and flux comparison.

Findings

Detected 170 X-ray sources in 0.7--7.0 keV band.

Identified sources include galaxies, clusters, SNRs, X-ray binaries, stars, and pulsars.

Approximately 10% of sources show flux changes since ROSAT survey.

Abstract

We present the first source catalog of the Solid-state Slit Camera (SSC) of the Monitor of All-sky X-ray Image (MAXI) mission on the International Space Station, using the 45-month data from 2010 August to 2014 April in 0.7--7.0~keV bands. Sources are searched for in two energy bands, 0.7--1.85~keV (soft) and 1.85--7.0~keV (hard), the limiting sensitivity of 3 and 4~mCrab are achieved and 140 and 138 sources are detected in the soft and hard energy bands, respectively. Combining the two energy bands, 170 sources are listed in the MAXI/SSC catalog. All but 2 sources are identified with 22 galaxies including AGNs, 29 cluster of galaxies, 21 supernova remnants, 75 X-ray binaries, 8 stars, 5 isolated pulsars, and 9 non-categorized objects. Comparing the soft-band fluxes at the brightest end in our catalog with the ROSAT survey, which was performed about 20 years ago, 10\% of the cataloged sources are found to have changed the flux since the ROSAT era.