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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 S190707q: AstroSat CZTI upper limits
  2. LIGO/Virgo S190707q: Updated sky localization
  3. LIGO/Virgo S190707q: MASTER OT seach result
  4. LIGO/Virgo S190707q: No counterpart candidates in the CNEOST
  5. LIGO/Virgo S190707q: No counterpart candidates in the Swift/BAT Observations
  6. IPN triangulation of GRB 190706D (short)
  7. IPN triangulation of GRB 190706C (long/very bright)
  8. LIGO/Virgo S190707q: Upper limits from CALET observations
  9. LIGO/Virgo S190707q: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S190707q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observations
  11. LIGO/Virgo S190707q: Upper limits from Fermi-GBM Observations
  12. LIGO/Virgo S190707q Global MASTER-Net observations report
  13. LIGO/Virgo S190707q: Upper limits from AGILE-GRID observations
  14. LIGO/Virgo S190707q: No counterpart candidates in AGILE-MCAL observations
  15. LIGO/Virgo S190707q: No counterpart candidates in HAWC observations
  16. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo S190707q : No neutrino counterpart candidates in ANTARES search
  18. LIGO/Virgo S190707q: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S190707q: Upper limits from IceCube neutrino searches

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Download all Circulars as a .tar.gz archive:
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