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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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 170311A: VLT observations
  2. GRB 170311A: Swift-BAT refined analysis
  3. GRB 170311A: Further GROND analysis
  4. GRB 170311A: Swift-XRT refined Analysis
  5. GRB 170311A: Swift/UVOT Upper Limits
  6. GRB 170311A: Enhanced Swift-XRT position
  7. GRB 170311A: GROND upper limits
  8. GRB 170311A: MASTER-OAFA early optical observations
  9. GRB 170311A: Swift detection of a burst

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