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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 S190720a: AstroSat CZTI upper limits
  2. LIGO/Virgo S190720a: Thacher Observatory follow-up observations
  3. IPN triangulation of GRB 190720A
  4. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  5. LIGO/Virgo S190720a: No counterpart candidates in CNEOST observations
  6. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  7. LIGO/Virgo S190720a: Upper limits from CALET observations
  8. LIGO/Virgo S190720a: No counterpart candidates in KAIT observations
  9. LIGO/Virgo S190720a: No counterpart candidates in the Swift/BAT Observations
  10. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  11. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  12. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  13. LIGO/Virgo S190720a: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  14. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190720a: AGILE-MCAL observations
  16. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo S190720a Global MASTER-Net observations report
  18. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  19. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches

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