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MAXI/GSC 7-Year High and Low Galactic Latitude Source Catalog (3MAXI)

Metadata Updated: September 19, 2025

This table combines the published X-ray source catalogs of the high galactic latitude (|b| > 10<sup>o</sup>), Kawamuro et 2018, and the low galactic latitude (|b| < 10<sup>o</sup>), Hori et al. 2018, based on 7 years of MAXI Gas Slit Camera (GSC) data from 2009 August 13 to 2016 July 31. The low galactic latitude catalog contains 221 sources with a significance threshold > 6.5 sigma. The low galactic faintest source has a flux of 5.2 x 10<sup>-12</sup> erg cm<sup>-2</sup> s<sup>-1</sup> (or an intensity of 0.43 mCrab) in the 4-10 keV band. The high galactic latitude catalog contains 686 sources detected at significances >= 6.5 sigma in the 4-10 keV band. The high galactic 4-10 keV sensitivity reaches ~0.48 mCrab, or ~5.9 x 10<sup>-12</sup> erg cm<sup>-2</sup> s<sup>-1</sup>, over half of the survey area. The same data-screening criteria were applied to obtain the low and high galactic catalogs. In their papers the authors describe the detection method, the statistical quantities derived for each source and their variability. To derive a counterpart, each source was cross-matched with the Swift/BAT 105-month catalog (BAT105; Oh et al. 2018), the Uhuru fourth catalog (4U; Forman et al. 1978), the RXTE All-Sky Monitor long-term observed source table (XTEASMLONG16), Meta-Catalog of X-Ray Detected Clusters of Galaxies (MCXC; Piffaretti et al. 2011), the XMM-Newton Slew Survey Catalog (XMMSL217), and the ROSAT All-Sky Survey Bright Source Catalog (1RXS; Voges et al. 1999). Seven of the sources in the low galactic latitudes were detected by binning the data differently (source numbers 215-221 in the catalog named 73-day sources), and, similarly, four of the sources in the high galactic latitude catalog named transient sources. The parameters in the combined table include the source name (3MAXI), the position and its error, the detection significances and fluxes in the 4-10 keV, 3-4 keV bands and 10-20 keV bands the hardness ratios (HR1: 3-4 keV, 4-10 keV and HR2: 4-10 keV, 10-20 keV), excess variance in the 4-10 keV lightcurve and information on the likely counterpart. The high galactic catalogs also reports the flux in the 3-10 keV, an additional hardness (HR3: 3-10 keV and 10-20 keV) and an additional parameter representing variability. The hardness ratios are defined as H-S/H+S were S and H are the soft- and hard-band fluxes, respectively. This table was created by the HEASARC in April 2021. It is a combination of the 7-year low- and high-latitude MAXI source catalogs published on ApJS. The data for the low-galactic latitude and the high-galactic latitude were downloaded from the ApJS electronic version of the Hori et al. 2018 ApJS 235,7 and Kawamuro et al. 2018 ApJS 238,33 papers respectively. The low-latitude data included in this table are from tables 4, 5, 6, 7 of the Hori paper that report the X-ray sources detected (214 sources, table 4), their possible identification (table 5), the transient sources discovered binning the data on 73 days period (7 sources, table 5) and their identification (table 6). The high-latitude data included in this table are from the tables 1,2,3 of the Kawamuro paper that report the X-ray sources detected (682 sources in table 1), their identifications (table 2), and the transient sources (4 sources in table 3). The low and high galactic latitude source catalogs provide for each individual source similar parameters for the X-ray properties with the high-latitude having three additional parameters, specifically, the flux in the 3-10 keV energy range, the 3-10/10-20-keV hardness ratio, and a time variability test. These parameters are kept in the HEASARC combined table and set to "blank" values for the low-latitude sources. The four sources in the high-latitude catalog named transient sources have only fluxes in the 4-10 keV band and no other fluxes in the other energy bands or the hardness ratio are reported. The HEASARC combined table includes a field to identify whether the source is from the low-latitude paper or the high-latitude paper and also maintains the source numbers that were published in the original catalogs. This is a service provided by NASA HEASARC .

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/maxigsc7yr
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id f2d3d569-66cc-4faf-bb91-249d2cd65f81
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/maxigsc7yr.html
Program Code 026:000
Source Datajson Identifier True
Source Hash ec085a79a671b2e12667aae948435011bd1a655bdee4703bc7f2df5cf5cf310c
Source Schema Version 1.1

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