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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"

21 results found.

  1. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  2. LIGO/Virgo S200225q: Upper limits from Konus-Wind observations
  3. LIGO/Virgo S200225q: No notable candidates in GOTO imaging
  4. LIGO/Virgo S200225q: AstroSat CZTI upper limits
  5. LIGO/Virgo S200225q : No significant candidates in TAROT - FRAM - GRANDMA observations.
  6. LIGO/Virgo S200225q: Not observable by CALET
  7. LIGO/Virgo S200225q: Updated Sky Localization
  8. LIGO/Virgo S200225q: no counterpart candidate in SVOM/GWAC observations
  9. LIGO/Virgo S200225q: Upper limits from Insight-HXMT/HE observations
  10. LIGO/Virgo S200225q: no counterpart candidates in the Swift/BAT observations
  11. LIGO/Virgo S200225q: Upper limits from Fermi-GBM Observations
  12. LIGO/Virgo S200225q: No counterpart candidates in Fermi-LAT observations
  13. LIGO/Virgo S200225q: upper limits from AGILE/GRID observations
  14. LIGO/Virgo S200225q: upper limits from AGILE/MCAL observations
  15. LIGO/Virgo S200225q: Upper limits from IceCube neutrino searches
  16. LIGO/Virgo S200225q: No counterpart candidates in HAWC observations
  17. LIGO/Virgo S200225q : no neutrino counterpart candidate in ANTARES search
  18. LIGO/Virgo S200225q: Global MASTER-Net observations report
  19. LIGO/Virgo S200225q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  20. LIGO/Virgo S200225q: Coverage and upper limits from MAXI/GSC observations
  21. LIGO/Virgo S200225q: Identification of a GW compact binary merger candidate The LIGO Scientific Collaboration and the Virgo Collaboration

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