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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"

24 results found.

  1. LIGO/Virgo G288732/GW170608: updated localization from parameter estimation
  2. LIGO/Virgo G288732: Konus-Wind observations
  3. LIGO/Virgo G288732: Fermi GBM Upper Limits for the LIGO Trigger and LAT Candidate
  4. LIGO/Virgo G288732: Pan-STARRS coverage of the Fermi/LAT candidate position
  5. LIGO/Virgo G288732: VLA imaging of the possible Fermi/LAT counterpart
  6. LIGO/Virgo G288732: Kiso/KWFC optical imaging of the possible Fermi/LAT counterpart
  7. LIGO/Virgo G288732: HAWC follow-up
  8. LIGO/Virgo G288732: UKIRT near-IR imaging of the Fermi/LAT candidate
  9. LIGO/Virgo G288732: LBT optical imaging of the Fermi/LAT candidate
  10. LIGO/Virgo G288732 : MAXI/GSC observations
  11. LIGO/Virgo G288732: Updated sky map from gravitational-wave data
  12. LIGO/Virgo G288732: GWFUNC/NOWT observations of the skymap and follow-up of the Fermi/LAT candidate
  13. LIGO/Virgo G288732: Swift/UVOT follow up of the possible LAT counterpart
  14. LIGO/Virgo G288732: Swift/BAT data search
  15. LIGO/Virgo G288732: Swift-XRT follow up of the putative LAT counterpart
  16. LIGO/Virgo G288732: INTEGRAL search for a prompt gamma-ray counterpart
  17. LIGO/Virgo G288732:SVOM/Mini-GWAC observations of the initial skymap
  18. LIGO/Virgo G288732: AGILE GRID Observations
  19. LIGO/Virgo G288732: Fermi-LAT detection of a weak candidate
  20. LIGO/Virgo G288732: IceCube neutrino observations update
  21. LIGO/Virgo G288732: AGILE MCAL Observations
  22. LIGO/Virgo G288732 ANTARES search
  23. LIGO/VIRGO G288732: Fermi GBM Observations
  24. LIGO/Virgo G288732: Identification of a GW Binary Merger Candidate

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Download all Circulars as a .tar.gz archive:
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