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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').

15 results found.

  1. GRB 090530: X-shooter redshift
  2. GRB 090530: Further NOT optical observations
  3. GRB 090530: RTT150 Optical Observation
  4. GRB 090530: Early RAPTOR Optical Observations
  5. GRB 090530: GRT Optical Observation
  6. GRB 090530: break in light curve
  7. GRB 090530: NOT optical observations
  8. GRB090530: Swift XRT refined analysis
  9. GRB090530: Swift/UVOT afterglow detection
  10. GRB 090530: Enhanced Swift-XRT position
  11. GRB 090530: Swift-BAT refined analysis
  12. GRB 090530: GRAS002 refined OA analysis
  13. GRB 090530: GRAS002 optical observations
  14. GRB 090530: PAIRITEL NIR Detections
  15. GRB 090530: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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