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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"

9 results found.

  1. GRB 250807B: Swift-BAT refined analysis
  2. GRB 250807B: SVOM/VT optical observation
  3. GRB 250807B: Swift/UVOT Detection
  4. GRB 250807B: Kilonova-Catcher optical afterglow detection
  5. GRB 250807B: VLT/X-Shooter spectroscopic redshift z = 1.522
  6. GRB 250807B: Swift-XRT refined Analysis
  7. GRB 250807B: NTT optical observations
  8. GRB 250807B: Enhanced Swift-XRT position
  9. GRB 250807B: Swift detection of a burst with an optical counterpart.

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

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