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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. VLA radio upper limit on GRB 080721
  2. GRB 080721 : Lulin 2nd optical follow-ups
  3. GRB 080721: OA fading and redshift
  4. GRB 080721: UVOT Follow-Up Observations
  5. Konus-Wind observation of GRB 080721
  6. GRB 080721: Swift-XRT refined analysis
  7. GRB 080721: Enhanced Swift-XRT position
  8. GRB 080721, Swift-BAT refined analysis
  9. GRB 080721: Swift/UVOT Photometric Redshift
  10. GRB 080721 : Lulin Optical follow-ups
  11. GRB 080721: Swift-XRT correct position
  12. GRB 080721: Swift detection of a burst with a bright optical counterpart.

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