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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"

22 results found.

  1. LIGO/Virgo S200219ac: AstroSat CZTI upper limits
  2. LIGO/Virgo S200219ac: Upper limits from Konus-Wind observations
  3. LIGO/Virgo S200219ac: Updated Sky Localization
  4. LIGO/Virgo S200219ac: No counterpart candidates from Nanshan/NEXT observations
  5. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  6. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  7. LIGO/Virgo S200219ac : No significant candidates in TAROT - FRAM - GRANDMA observations.
  8. IPN triangulation of GRB 200219B (inconsistent with the LIGO/Virgo S200219ac)
  9. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  10. LIGO/Virgo S200219ac: No transient candidates in CALET observations
  11. LIGO/Virgo S200219ac: no counterpart candidates in the Swift/BAT observations
  12. LIGO/Virgo S200219ac: Fermi GBM transient event not confidently associated with GW signal
  13. LIGO/Virgo S200219ac: No counterpart candidates in Fermi-LAT observations
  14. LIGO/Virgo S200219ac: upper limits from AGILE/GRID observations
  15. LIGO/Virgo S200219ac: upper limits from AGILE/MCAL observations
  16. LIGO/Virgo S200219ac : no neutrino counterpart candidate in ANTARES search
  17. LIGO/Virgo S200219ac: Upper limits from IceCube neutrino searches
  18. LIGO/Virgo S200219ac: No counterpart candidates in HAWC observations
  19. LIGO/Virgo S200219ac: Coverage and upper limits from MAXI/GSC observations
  20. LIGO/Virgo S200219ac: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  21. LIGO/Virgo S200219ac: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S200219ac: Global MASTER-Net observations report

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