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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"

23 results found.

  1. LIGO/Virgo S190521r: Gaia Photometric Alerts transient candidate
  2. LIGO/Virgo S190521r : Gaia Photometric Alerts transient candidate
  3. LIGO/Virgo S190521g: AstroSat CZTI upper limits
  4. LIGO/Virgo S190521r: CNEOST follow-up observations
  5. LIGO/Virgo S190521r: Kanata optical/NIR follow-up observations of the CNEOST Transient
  6. LIGO/Virgo S190521r: No optical counterpart from SVOM/GWAC-F30 observations.
  7. LIGO/Virgo S190521r: No optical counterpart from SVOM/GWAC observations.
  8. LIGO/Virgo S190521r: No candidate counterparts from ATLAS observations of the skymap
  9. LIGO/Virgo S190521r: RATIR Optical and NIR Observations of the CNEOST Transient
  10. LIGO/Virgo S190521r: No transient candidates from CALET observations
  11. LIGO/Virgo S190521r: One optical transient from CNEOST
  12. LIGO/Virgo S190521r: Swift/BAT Counterpart Search
  13. LIGO/Virgo S190521r: Coverage and upper limits from Fermi-LAT observations
  14. LIGO/Virgo S190521r: Upper limits from Fermi-GBM observations
  15. LIGO/Virgo S190521r: Upper limits from AGILE-GRID observations
  16. LIGO/Virgo S190521r Global MASTER-Net observations report
  17. LIGO/Virgo S190521r: No counterpart candidate in AGILE-MCAL observations
  18. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  19. LIGO/Virgo S190521r: No neutrino counterpart candidates in ANTARES search
  20. LIGO/Virgo S190521r: IceCube Neutrino Search
  21. LIGO/Virgo S190521r: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S190521r: No counterpart candidates in HAWC observations
  23. LIGO/Virgo S190521r: No counterpart candidates in INTEGRAL SPI/ACS prompt observation

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