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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"

18 results found.

  1. LIGO/Virgo S200208q: Upper limits from Konus-Wind observations
  2. LIGO/Virgo S200208q : No significant candidates in TAROT - FRAM - GRANDMA observations
  3. LIGO/Virgo S200208q: no counterpart candidate in SVOM/C-GFT observations
  4. LIGO/Virgo S200208q: Updated Sky Localization
  5. LIGO/Virgo S200208q: No counterpart candidates in KAIT observations
  6. LIGO/Virgo S200208q: Not observable by CALET
  7. LIGO/Virgo S200208q: No counterpart candidates in Fermi-LAT observations
  8. LIGO/Virgo S200208q: Coverage and upper limits from MAXI/GSC observations
  9. LIGO/Virgo S200208q: no counterpart candidates in the Swift/BAT observations
  10. LIGO/Virgo S200208q: Upper limits from Fermi-GBM Observations
  11. LIGO/Virgo S200208q : upper limits from AGILE/GRID observations
  12. LIGO/Virgo S200208q: upper limits from AGILE/MCAL observations
  13. LIGO/Virgo S200208q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  14. LIGO/Virgo S200208q: Global MASTER-Net observations report
  15. LIGO/Virgo S200208q: No counterpart candidates in HAWC observations
  16. LIGO/Virgo S200208q : no neutrino counterpart candidate in ANTARES search
  17. LIGO/Virgo S200208q: Upper limits from IceCube neutrino searches
  18. LIGO/Virgo S200208q: Identification of a GW compact binary merger candidate

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Download all Circulars as a .tar.gz archive:
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