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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

9 results found.

  1. GRB110212A: MITSuME Okayama optical upper limits
  2. GRB 110201A: Subaru/MOIRCS Ks-band photometry
  3. GRB 110201A: optical observations
  4. GRB 110201A: Swift-XRT refined Analysis
  5. GRB110201A: MITSuME Okayama optical upper limits
  6. Swift/UVOT observations of GRB110201A
  7. GRB 110201A: Swift-BAT refined analysis
  8. GRB 110201A: MASTER optical observations
  9. GRB 110201A: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive:
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