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ASCA Large Sky Survey

Metadata Updated: August 30, 2025

The ASCA Large Sky Survey (LSS) was the first wide-area unbiased survey with the ASCA satellite in the 0.7 - 10 keV band around the North Galactic Pole region covering a continuous area of 7 square degrees. To make the best use of ASCA's capabilities, the authors developed a new source detection method in which the complicated detector responses were fully taken into account. Applying this method to the entire LSS data independently in the total (0.7 - 7 keV), hard (2 - 10 keV), and soft (0.7 - 2 keV) bands, they detected 107 sources altogether, with sensitivity limits of 6 x 10<sup>-14</sup> (0.7 - 7 keV), 1 x 10<sup>-13</sup> (2 - 10 keV), and 2 x 10<sup>-14</sup> ergs/s/cm<sup>2</sup> (0.7 - 2 keV), respectively. The complete list of detected sources is presented in this table. The detection criteria that needed to be satisfied were: (i) the significance of the summed count rate of the GIS and the SIS should exceed 4.5, and (ii) the significance of either the GIS or the SIS should also exceed 3.5. This database was created by the HEASARC in December 2001 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/518/656">CDS Catalog J/ApJ/518/656</a>. 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.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date August 30, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date August 30, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/ascalss
Data Last Modified 2025-08-27
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 b58365f6-397e-4f67-8b56-e34f56ed57ea
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/ascalss.html
Program Code 026:000
Source Datajson Identifier True
Source Hash f9fdc9c76772e21ba9f8c593874aedad97fb8aa19426f65e76736000b9b73bb5
Source Schema Version 1.1

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