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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. GRB 230606A: LCOGT Optical Observations
  2. GRB 230606A: Swift-BAT refined analysis
  3. GRB 230606A: Gaoyazi/GOT optical upper limit
  4. GRB 230606A: Fermi GBM Observation
  5. GRB 230606A: BOOTES-5/JGT optical upper limit
  6. GRB 230606A: Swift-XRT refined Analysis
  7. GRB 230606A: Swift/UVOT Upper Limits
  8. GRB 230606A: Enhanced Swift-XRT position
  9. GRB 230606A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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