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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"

19 results found.

  1. LIGO/Virgo S190828l: Updated Sky Localization
  2. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  3. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  4. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  5. LIGO/Virgo S190828l: Upper limits from Insight-HXMT/HE observations
  6. LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
  7. LIGO/Virgo S190828l: No transient candidates in CALET observations
  8. LIGO/Virgo S190828l: no counterpart candidates in the Swift/BAT Observations
  9. LIGO/Virgo S190828l: Upper limits from Fermi-GBM Observations
  10. LIGO/Virgo S190828l: Upper limits from AGILE-GRID observations
  11. LIGO/Virgo S190828l: Upper limits from IceCube neutrino searches
  12. LIGO/Virgo S190828l Global MASTER-Net observations report
  13. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S190828l: No counterpart candidates in AGILE-MCAL observations
  15. LIGO/Virgo S190828l : no neutrino counterpart candidate in ANTARES search
  16. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  17. LIGO/Virgo S190828j: Updated Sky Localization
  18. LIGO/Virgo S190828l: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S190828l: No counterpart candidates in HAWC observations

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