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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"

7 results found.

  1. GRB 151210A: Swift/UVOT Upper Limits
  2. GRB 151210A: Swift-BAT refined analysis
  3. GRB 151210A: Swift-XRT refined Analysis
  4. GRB 151210A: Enhanced Swift-XRT position
  5. GRB 151210A: GROND Afterglow Confirmation
  6. GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
  7. GRB 151210A: Swift detection of a burst

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Download all Circulars as a .tar.gz archive:
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