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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

14 results found.

  1. GRB 251201B: SALT spectroscopic redshift z = 1.599
  2. GRB 251201B: Insight-HXMT/HE detection
  3. GRB 251201B: Fermi GBM Observation
  4. GRB 251201B: Kilonova-Catcher optical afterglow detection
  5. GRB 251201B: Swift/UVOT Detection
  6. GRB 251201B: GECAM-B observation of a long burst
  7. GRB 251201B: Swift-XRT refined Analysis
  8. GRB 251201B: SVOM/VT optical fading
  9. Swift GRB 251201B : MASTER optical counterpart detection
  10. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  11. Swift GRB 251201B: Global MASTER-Net observations report
  12. GRB 251201B: Enhanced Swift-XRT position
  13. GRB 251201B: Swift detection of a burst with an optical counterpart
  14. GRB 251201B: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
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Open an issue.
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Get involved on GitHub.

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