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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').

9 results found.

  1. Konus-Wind observation of GRB 180704A
  2. GRB 180704A: AstroSat CZTI detection
  3. GRB 180704A: Swift-XRT refined Analysis
  4. GRB 180704A: Swift-BAT refined analysis
  5. GRB 180704A: Swift/UVOT Upper Limits
  6. GRB 180704A: Enhanced Swift-XRT position
  7. GRB 180704A: Swift-XRT observations
  8. GRB 180704A: MASTER optical observation
  9. GRB 180704A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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