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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

14 results found.

  1. LIGO/Virgo S191109d: Not observable by CALET
  2. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  3. LIGO/Virgo S191109d: No counterpart candidates in Fermi-LAT observations
  4. LIGO/Virgo S191109d: AstroSat CZTI upper limits
  5. LIGO/Virgo S191109d: no counterpart candidates in the Swift/BAT observations
  6. LIGO/Virgo S191109d : no neutrino counterpart candidate in ANTARES search
  7. LIGO/Virgo S191109d: Global MASTER-Net observations report
  8. LIGO/Virgo S191109d: upper limits from AGILE-GRID observations mailed-by:
  9. LIGO/Virgo S191109d: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  10. LIGO/Virgo S191109d: upper limits from AGILE/MCAL observations
  11. LIGO/Virgo S191109d: Upper limits from Fermi-GBM Observations
  12. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  13. LIGO/Virgo S191109d: Upper limits from IceCube neutrino searches
  14. LIGO/Virgo S191109d: Identification of a GW compact binary merger candidate

Advanced

Download all Circulars as a .tar.gz archive:
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