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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"

11 results found.

  1. GRB 241218A: Mondy AZT-33IK optical upper limit
  2. GRB 241218A: Swift/UVOT Upper Limits
  3. GRB 241218A: NOT optical upper limits
  4. GRB 241218A: Swift-BAT refined analysis
  5. GRB 241218A: REM optical upper limit
  6. GRB 241218a: Liverpool Telescope optical follow-up
  7. GRB 241218A: Swift-XRT refined Analysis
  8. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  9. GRB 241218A: LCOGT Optical Upper Limit
  10. GRB 241218A: Enhanced Swift-XRT position
  11. GRB 241218A: Swift detection of a burst

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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