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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 180618A: AstroSat CZTI detection
  2. Konus-Wind observation of GRB 180618A (a short GRB with extended emission)
  3. GRB 180618A: Swift/UVOT Detection
  4. GRB 180618A: TSHAO optical upper limit
  5. GRB 180618A: Xinglong-2.16m optical upper limit
  6. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  7. GRB 180618A: Swift-BAT refined analysis (a short GRB with extended emission)
  8. GRB 180618A: Fermi GBM detection
  9. GRB 180618A: Swift-XRT refined Analysis
  10. GRB 180618A: LT prompt observations
  11. GRB 180618A: Enhanced Swift-XRT position
  12. GRB 180618A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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