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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 200411A: Chandra observations indicative of temporal steepening
  2. GRB 200411A: ATCA 5/9 GHz radio observations
  3. GRB 200411A: Swift-BAT refined analysis
  4. GRB 200411A: Fermi GBM observation
  5. Swift GRB 200411A: Global MASTER-Net observations report
  6. GRB 200411A: Swift-XRT refined Analysis
  7. GRB 200411A: Swift/UVOT Upper Limits
  8. GRB 200411A: Enhanced Swift-XRT position
  9. GRB 200411A: Swift detection of a short burst
  10. GRB 200411A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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