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LALA Bootes Field Chandra X-Ray Point Source Catalog

Metadata Updated: August 30, 2025

This table contains the results of an analysis of a deep, 172 ks Chandra observation of the Large Area Lyman Alpha survey (LALA) Bootes field which was obtained with the Advanced CCD Imaging Spectrometer (ACIS-I) on board the Chandra X-Ray Observatory. This is one of the deepest Chandra images of the extragalactic sky, with only the 2 Ms Chandra Deep Field North (CDF-N) and the 1 Ms Chandra Deep Field South (CDF-S) observations being substantially deeper. In this table, the X-ray source catalog obtained from this image is presented, along with some results from an analysis of the X-ray source counts and optical identifications. The X-ray image is composed of two individual observations obtained in 2002 and reaches 0.5 - 2.0 and 2.0 - 10.0 keV flux limits of 1.5 x 10<sup>-16</sup> and 1.0 x 10<sup>-15</sup> ergs/cm<sup>2</sup>/s, respectively, for point sources near the aim point. A total of 168 X-ray sources were detected: 160 in the 0.5 - 7.0 keV band, 132 in the 0.5 - 2.0 keV band, and 111 in the 2.0 - 7.0 keV band. Since X-ray source number 122 has two possible optical counterparts, it is listed twice, once for each counterpart, and the total number of entries in this table is this 169. The primary optical data are R-band imaging from the NOAO Deep Wide-Field Survey (NDWFS), with a limiting magnitude of R = 25.7 magnitudes, (Vega, 3-sigma detection level, and a 4" diameter aperture). Optical counterparts within 1.5" or the 3-sigma X-ray positional uncertainties, whichever was larger, were detected above this level in the R band for 144 of the 168 X-ray sources. At least 90% of the optical counterparts should be the correct matches, and, at worst, there might be ~14 false matches. This table was created by the HEASARC in March 2007 based on the CDS table J/AJ/127/213 file table1.dat, 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 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/lalaboocxo
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 10dd2642-9e82-4aae-acaf-7896483209d5
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/lalaboocxo.html
Program Code 026:000
Source Datajson Identifier True
Source Hash fc052b75f918daa1112f703de2d0b73ce21f0adf51e628c8fd86727c718828b6
Source Schema Version 1.1

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