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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').

10 results found.

  1. GRB 230911C: ATCA detection of possible radio counterpart
  2. GRB 230911C: Swift-XRT refined Analysis
  3. GRB 230911C: Swift-BAT refined analysis
  4. GRB230911C: BOOTES-6/DPRT optical upper limit
  5. Swift GRB 230911C: Global MASTER-Net observations report
  6. GRB230911C: LCOGT Optical Upper Limits
  7. GRB 230911C: Swift/UVOT Upper Limits
  8. GRB 230911C: GOTO optical upper limits
  9. GRB 230911C: Enhanced Swift-XRT position
  10. GRB 230911C: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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