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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 090727: GRT Optical Observation
  2. GRB 090727: optical observations
  3. GRB 090727: Swift/UVOT Upper Limits
  4. GRB 090727: I-band observations from 1.23m CAHA
  5. GRB 090727: Swift-BAT refined analysis
  6. GRB 090727: Swift-XRT refined analysis
  7. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  8. GRB 090727: Enhanced Swift-XRT position
  9. GRB 090727: Liverpool Telescope possible OT candidate
  10. GRB 090727: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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