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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').

11 results found.

  1. GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
  2. GRB 151021A: MITSuME Okayama Ks-band upper-limit
  3. Konus-Wind observation of GRB 151021A
  4. GRB 151021A: Swift/UVOT Detection
  5. GRB 151021A: MITSuME Okayama upper limits
  6. GRB 151021A: Swift-XRT refined Analysis
  7. GRB 151021A: Swift-BAT refined analysis
  8. GRB 151021A: Enhanced Swift-XRT position
  9. GRB 151021A: MASTER-NET bright OT detection
  10. GRB 151021A: Optical counterpart and redshift from X-shooter
  11. GRB 151021A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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