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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').

12 results found.

  1. GRB 090531B: Fermi GBM detection
  2. GRB 090531b, SMARTS optical/IR observations
  3. GRB 090531B: GROND observation
  4. GRB 090531B: Swift/BAT spectral lag results
  5. Corrections to GRB 090531B Swift/UVOT Upper Limits
  6. GRB 090531B, RIMOTS optical upper limits
  7. GRB 090531B: Swift/UVOT Upper Limits
  8. GRB 090531B: Swift-BAT refined analysis
  9. Initial Swift/UVOT observations of GRB 090531B
  10. GRB 090531B: Swift-XRT candidate afterglow position
  11. GRB 090531B: ROTSE-III Optical Limits
  12. GRB 090531B: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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