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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"

12 results found.

  1. GRB190109B: MITSuME Akeno optical upper limits
  2. GRB 190109B: Fermi GBM observation
  3. GRB 190109B: Swift/UVOT Upper Limits
  4. GRB 190109B: Swift-XRT refined Analysis
  5. GRB 190109B: Swift-BAT refined analysis
  6. Correction to the GCN circ. 23654 / GRB 190109B: Mondy optical upper limit
  7. GRB 190109B: COATLI Optical Observations
  8. GRB 190109B: BOOTES-5/JGT optical observations
  9. GRB 190109B: Mondy optical upper limit
  10. GRB 190109B: Enhanced Swift-XRT position
  11. GRB 190109B: Swift-XRT observations
  12. GRB 190109B: Swift detection of a burst

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Download all Circulars as a .tar.gz archive:
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