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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"

21 results found.

  1. LIGO/Virgo S190924h: Correction to GCN 25905, updated sky localization for S190924h
  2. LIGO/Virgo S190828h: Updated Sky Localization
  3. LIGO/Virgo S190828j: Updated Sky Localization
  4. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  5. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  6. LIGO/Virgo S190828j: No Counterparts in DDOTI/OAN Optical Observations
  7. LIGO/Virgo S190828j: No transient candidates in CALET observations
  8. LIGO/Virgo S190828j: no counterpart candidates in the Swift/BAT Observations
  9. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  10. LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
  11. LIGO/Virgo S190828j: Upper limits from Fermi-GBM Observations
  12. LIGO/Virgo S190828j: Upper limits from IceCube neutrino searches
  13. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S190828j : no neutrino counterpart candidate in ANTARES search
  15. LIGO/Virgo S190828j: Upper limits from AGILE-GRID observations
  16. LIGO/Virgo S190828j: Updated Sky Localization
  17. LIGO/Virgo S190828l: Identification of a GW compact binary merger candidate
  18. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  19. LIGO/Virgo S190828j: No counterpart candidates in HAWC observations
  20. LIGO/Virgo S190828j: No counterpart candidates in AGILE-MCAL observations
  21. LIGO/Virgo S190828j: Identification of a GW compact binary merger candidate

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