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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"

10 results found.

  1. GRB 160912A: 15 GHz upper limits from AMI
  2. GRB 160912A, Swift-BAT refined analysis
  3. GRB 160912A: RATIR Optical and NIR Observations
  4. GRB 160912A: Swift/UVOT Weak Afterglow Detection
  5. GRB 160912A: Mondy optical observations
  6. GRB 160912A Liverpool Telescope optical afterglow
  7. GRB 160912A: Swift-XRT refined Analysis
  8. GRB 160912A: Fermi GBM detection
  9. GRB 160912A: Enhanced Swift-XRT position
  10. GRB 160912A: Swift detection of a burst

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