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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').

17 results found.

  1. GRB 150203A iTelescope observation
  2. GRB 150203A: Swift-BAT refined analysis
  3. GRB 150203A: RAPTOR Limits Beginning at the Gamma-Ray Emitting Interval
  4. GRB 150203A: Swift/UVOT Upper Limits
  5. GRB 150203A: ISON-NM early optical limit
  6. GRB 150203A: Swift-XRT refined Analysis
  7. GRB 150203A: MITSuME Okayama upper limits
  8. GRB 150203A: REM optical and NIR observations
  9. GRB 150203A: Fermi GBM observation
  10. GRB 150203A: TAROT La Silla observatory optical observations
  11. GRB 150203A: GROND Upper limits
  12. GRB 150203A: Enhanced Swift-XRT position
  13. GRB 150203A: RATIR Optical and NIR Observations
  14. GRB 150203A: P60 observations
  15. GRB 150203A: KAIT Optical Upper Limit
  16. GRB 150203A: Prompt enhanced Swift-XRT position
  17. GRB 150203A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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