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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"

17 results found.

  1. LIGO/Virgo S191105e: Updated Sky Localization
  2. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  3. LIGO/Virgo S191105e: Upper limits from Insight-HXMT/HE observations
  4. LIGO/Virgo S191105e: AstroSat CZTI upper limits
  5. LIGO/Virgo S191105e: Not observable by CALET
  6. LIGO/Virgo S191105e: No counterpart candidates in Fermi-LAT observations
  7. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S191105e: no counterpart candidates in the Swift/BAT observations
  9. LIGO/Virgo S191105e : no neutrino counterpart candidate in ANTARES search
  10. LIGO/Virgo S191105e: No counterpart candidates in HAWC observations
  11. LIGO/Virgo S191105e: No counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  12. LIGO/Virgo S191105e: upper limits from AGILE/GRID observations
  13. LIGO/Virgo S191105e: Upper limits from Fermi-GBM Observations
  14. LIGO/Virgo S191105e: Global MASTER-Net observations report
  15. LIGO/Virgo S191105e: upper limits from AGILE/MCAL observations
  16. LIGO/Virgo S191105e: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo S191105e: Upper limits from IceCube neutrino searches

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