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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 S200302c: Upper limits from Konus-Wind observations
  2. LIGO/Virgo S200302c: No notable candidates in GOTO imaging
  3. LIGO/Virgo S200302c : No significant candidates in FRAM - TAROT - GRANDMA observations.
  4. LIGO/Virgo S200302c: AstroSat CZTI upper limits
  5. LIGO/Virgo S200302c: Upper limits from Insight-HXMT/HE observations
  6. LIGO/Virgo S200302c: No transient candidates in CALET observations
  7. LIGO/Virgo S200302c: Updated Sky Localization
  8. LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations
  9. LIGO/Virgo S200302c: No counterpart candidates in KAIT observations
  10. LIGO/Virgo S200302c: no counterpart candidates in the Swift/BAT observations
  11. LIGO/Virgo S200302c: No counterpart candidates in HAWC observations
  12. LIGO/Virgo S200302c: Upper limits from Fermi-GBM Observations
  13. LIGO/Virgo S200302c: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  14. LIGO/Virgo S200302c : no neutrino counterpart candidate in ANTARES search
  15. LIGO/Virgo S200302c: upper limits from AGILE/MCAL observations
  16. LIGO/Virgo S200302c: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo S200302c: Upper limits from IceCube neutrino searches
  18. LIGO/Virgo S200302c: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S200302c: Global MASTER-Net observations report

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