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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"

10 results found.

  1. GRB 240819A: Optical upper limits from TESS
  2. GRB 240819A as a likely X-Ray Flash
  3. GRB 240819A: Swift afterglow confirmation
  4. GRB 240819A: Swift-XRT observations
  5. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  6. GRB 240819A: KAIT optical upper limit
  7. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  8. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  9. GRB 240819A: X-ray follow-up observation with EP-FXT
  10. GRB 240819A: Swift ToO observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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