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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 210731A: continued GROND observations
  2. GRB 210731A: VLT/X-shooter redshift
  3. GRB 210731A: KAIT Optical Detection
  4. GRB 210731A: Swift-BAT refined analysis
  5. GRB 210731A: MASTER optical afterglow detection
  6. GRB 210731A: Swift-XRT refined Analysis
  7. GRB 210731A: GROND observations
  8. GRB 210731A: Fermi GBM Observation
  9. GRB 210731A: Swift/UVOT Detection of an optical afterglow
  10. GRB 210731A: MeerLICHT optical afterglow detection
  11. GRB 210731A: 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.

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