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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 S190630ag: Updated sky localization
  2. LIGO/Virgo S190630ag: Gaia Photometric Alerts transient candidate
  3. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  4. IPN triangulation of GRB 190630A (short)
  5. LIGO/Virgo S190630ag: Upper limits from Insight-HXMT/HE observations
  6. LIGO/Virgo S190630ag: Upper limits from CALET observations
  7. LIGO/Virgo S190630ag: No counterpart candidates in KAIT observation
  8. LIGO/Virgo S190630ag: No counterpart candidates in AGILE-GRID observations
  9. LIGO/Virgo S190630ag: No counterpart candidates in the Swift/BAT Observations
  10. LIGO/Virgo S190630ag: No counterpart candidates in AGILE-MCAL observations
  11. LIGO/Virgo S190630ag: No counterpart candidates in Fermi-LAT observations
  12. LIGO/Virgo S190630ag: Upper limits from Fermi-GBM Observations
  13. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S190630ag: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  15. LIGO/Virgo S190630ag: No neutrino counterpart candidates in ANTARES search
  16. LIGO/Virgo S190630ag: No counterpart candidates in HAWC observations
  17. LIGO/Virgo S190630ag: Identification of a GW compact binary merger candidate
  18. LIGO/Virgo S190630ag Global MASTER-Net observations report
  19. LIGO/Virgo S190630ag: Upper limits from IceCube neutrino searches

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