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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"

20 results found.

  1. LIGO/Virgo S200316bj: Upper limits from Konus-Wind observations
  2. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC-F30 observations
  3. LIGO/Virgo S200316bj: Updated Sky Localization and EM Bright Classification
  4. LIGO/Virgo S200316bj : No significant candidates in TAROT - FRAM - GRANDMA observations.
  5. LIGO/Virgo S200316bj: Upper limits from Insight-HXMT/HE observations
  6. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC observations
  7. LIGO/Virgo S200316bj: Upper limits from CALET observations
  8. LIGO/Virgo S200316bj: No neutrino candidates at Pierre Auger Observatory
  9. LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S200316bj: No Counterparts in DDOTI/OAN Optical Observations
  11. LIGO/Virgo S200316bj: no counterpart candidates in the Swift/BAT observations
  12. LIGO/Virgo S200316bj: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  13. LIGO/Virgo S200316bj: upper limits from AGILE/GRID observations
  14. LIGO/Virgo S200316bj: upper limits from AGILE/MCAL observations
  15. LIGO/Virgo S200316bj: Upper limits from Fermi-GBM Observations
  16. LIGO/Virgo S200316bj: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo S200316bj : no neutrino counterpart candidate in ANTARES search
  18. LIGO/Virgo S200316bj: Upper limits from IceCube neutrino searches
  19. LIGO/Virgo S200316bj: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo S200316bj: Global MASTER-Net observations report

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