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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').

8 results found.

  1. GRB 200917A: Swift/UVOT Upper Limits
  2. GRB 200917A: GROWTH-India Telescope optical upper limit.
  3. GRB 200917A: Swift-BAT refined analysis
  4. Fermi-GBM Sub-Threshold Detection of GRB 200917A
  5. GRB 200917A: Swift-XRT refined Analysis
  6. Swift GRB 200917A: Global MASTER-Net observations report
  7. GRB 200917A: Enhanced Swift-XRT position
  8. GRB 200917A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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