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Resource Record Summary

Catalog Service:
M 81 Chandra X-Ray Point Source Catalog

Short name: M81CXO2
IVOA Identifier: ivo://nasa.heasarc/m81cxo2Publisher: NASA/GSFC HEASARCivo://nasa.heasarc/ASD[Pub. ID]
More Info: https://heasarc.gsfc.nasa.gov/W3Browse/all/m81cxo2.html
VO Compliance: Level 2: This is a VO-compliant resource.
Status: active
Registered: 2024 Jun 21 00:00:00Z
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Description


This table contains the source table from an analysis of 15 Chandra ACIS observations of the nearby spiral galaxy M81 taken over the course of six weeks in 2005 May-July. Each observation reaches a sensitivity of ~10<sup>37</sup> erg s<sup>-1</sup>. With these observations and one previous deeper Chandra observation (the properties of which are described in Table 1 and Section 2 of the reference paper), the authors have compiled a master source list of 265 point sources, extracted and fitted their spectra, and differentiated basic populations of sources through their colors. They also carried out variability analyses of individual point sources and of X-ray luminosity functions (XLFs) in multiple regions of M 81 on timescales of days, months, and years. They find that, despite measuring significant variability in a considerable fraction of sources, snapshot observations provide a consistent determination of the XLF of M81. They also fit the XLFs for multiple regions of M81 and, using common parametrization, compare these luminosity functions to those of two other spiral galaxies, M31 and the Milky Way. This table contains the 265 point sources at or above the 99.9% probability level of being real according to AE's PROB_NO_SOURCE statistic (the "master" source list), and 11 additional "borderline" sources which have 99.0-99.9% probability of being real according to AE's PROB_NO_SOURCE statistic, for a total of 276 sources whose properties were described in Tables 3 and 4 of the reference paper. The 265 "master" sources have source numbers from 1 to 265 while the 11 "borderline" sources have source numbers beginning with 'B', e.g., they have source numbers 'B1' to 'B11'. Note that only coordinates are listed for 3 sources in the master source list (source numbers 234, 241 and 262) and 2 sources in the borderline source list (B8 and B9) because they were only in the field of view (on chip) of one observation (ObsID 735). Six additional sources near the center of M81 which were found using maximum likelihood image reconstruction are not included in either the master or borderline source lists contained herein but their positions are listed in table 2 of the reference paper. This table was created by the HEASARC in August 2011 based on electronic versions of Tables 3 and 4 from the reference paper which were obtained from the ApJ web site. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .

More About this Resource

About the Resource Providers

This section describes who is responsible for this resource

Publisher: NASA/GSFC HEASARCivo://nasa.heasarc/ASD[Pub. ID]

Creator: Sell et al. Contributor:

Contact Information:
X NASA/GSFC HEASARC help desk
Email:

Status of This Resource

This section provides some status information: the resource version, availability, and relevant dates.

Version: n/a
Availability: This is an active resource.
  • This service apparently provides only public data
Relevant dates for this Resource:
  • Representative: 2024 Jun 21

This resource was registered on: 2024 Jun 21 00:00:00Z
This resource description was last updated on: 2024 Jun 21 00:00:00Z

What This Resource is About

This section describes what the resource is, what it contains, and how it might be relevant.

Resource Class: CatalogService
This resource is a service that provides access to catalog data. You can extract data from the catalog by issuing a query, and the matching data is returned as a table.
Resource type keywords:
  • Catalog
Subject keywords:
  • Survey Source
This service provides data from:
  • facility: CHANDRA
Intended audience or use:
  • Research: This resource provides information appropriate for supporting scientific research.
More Info: https://heasarc.gsfc.nasa.gov/W3Browse/all/m81cxo2.html Literature Reference: 2011ApJ...735...26S

Related Resources:

Services that provide access to data in this resource:
HEASARC TAP ivo://nasa.heasarc/services/xamin [Res. ID]

Data Coverage Information

This section describes the data's coverage over the sky, frequency, and time.

Reference Coordinate System: UTC-ICRS-TOPOXXivo://STClib/CoordSys#UTC-ICRS-TOPO[Res. ID]

Sky Coverage: Regions covered:

  • All-sky: The data from this resource is distributed over the entire sky.
Typical Size Scale (Region of Regard): , 0.0166666666666667 deg

Wavebands covered:

  • X-ray

Available Service Interfaces

Simple Cone SearchXXSearch Me

This is a standard IVOA service that takes as input a position in the sky and a radius and returns catalog records with positions within that radius.

VO Compliance: Level 2: This is a VO-compliant resource.
Available endpoints for the standard interface:
  • https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=m81cxo2&
Maximum search radius accepted: 180 degrees
Maximum number of matching records returned: 99999
This service supports the VERB input parameter:
Use VERB=1 to minimize the returned columns or VERB=3 to maximize.
Table Access Protocol - Auxiliary ServiceXX

This is a standard IVOA service that takes as input an ADQL or PQL query and returns tabular data.

VO Compliance: Level 2: This is a VO-compliant resource.
Available endpoints for the standard interface:
  • https://heasarc.gsfc.nasa.gov/xamin/vo/tap
Custom Service

This is service that does not comply with any IVOA standard but instead provides access to special capabilities specific to this resource.

VO Compliance: Level 2: This is a VO-compliant resource.
Available endpoints for this service interface:
  • URL-based interface: https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=m81cxo2
Custom Service

This is service that does not comply with any IVOA standard but instead provides access to special capabilities specific to this resource.

VO Compliance: Level 2: This is a VO-compliant resource.
Available endpoints for this service interface:


Developed with the support of the National Science Foundation
under Cooperative Agreement AST0122449 with the Johns Hopkins University
The NAVO project is a member of the International Virtual Observatory Alliance

This NAVO Application is hosted by the Space Telescope Science Institute

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