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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').

14 results found.

  1. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  2. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  3. GRB 230420A: AROMA-N Optical Upper Limit
  4. GRB 230420A: Lowell Discovery Telescope Optical Detection
  5. GRB 230420A: Swift/UVOT Upper Limits
  6. GRB 230420A: Swift-BAT refined analysis
  7. GRB 230420A: Swift-XRT refined Analysis
  8. GRB 230420A: MITSuME Akeno optical observation
  9. GRB 230420A: NOT optical afterglow confirmation
  10. GRB 230420A: Gaoyazi/GOT optical upper limit
  11. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  12. GRB 230420A: LCOGT Optical Upper Limit
  13. GRB 230420A: Enhanced Swift-XRT position
  14. GRB 230420A: Swift detection of a burst


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