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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. Title: GRB 090809: Further NOT optical observations
  2. VLA radio upper limit on GRB 090809
  3. GRB 090809: WHT observations
  4. GRB 090809 X-shooter redshift
  5. GRB 090809: Swift-XRT refined analysis
  6. GRB090809: Swift/UVOT observations
  7. GRB 090809: Enhanced Swift-XRT position
  8. GRB 090809: Swift-BAT refined analysis
  9. GRB 090809: afterglow confirmation at the NOT
  10. GRB 090809: Swift detection of a burst with a possible optical counterpart


Download all Circulars as a .tar.gz archive:
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