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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 S190727h: Updated sky localization
  2. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  3. LIGO/Virgo S190727h: Gaia Photometric Alerts transient candidate
  4. LIGO/Virgo S190727h: No transient candidates in CALET observations
  5. LIGO/Virgo S190727h: No counterpart candidates in KAIT observations
  6. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  7. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  8. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  9. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  10. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  11. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  12. LIGO/Virgo S190727h: No counterpart candidates in AGILE-MCAL observations
  13. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  14. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  16. LIGO/Virgo S190727h Global MASTER-Net observations report
  17. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches

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