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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').

18 results found.

  1. KAIT Optical Upper Limits for GRB 120422A, 120724A, 120803B, 120911A, and 120923A
  2. GRB 120923A: Correction to GCN 13823
  3. GRB 120923A: JHK Observation
  4. GRB 120923A: optical upper limit
  5. GRB 120923A: RAPTOR Early Afterglow Limits
  6. GRB 120923A: MITSuME Okayama Optical upper limits
  7. GRB 120923A: RAPTOR Limits During Gamma-Ray Emitting Interval
  8. GRB 120923A: CARMA Observations
  9. GRB 120923A: EVLA Observations
  10. GRB 120923A: Swift-XRT refined Analysis
  11. GRB 120923A: GROND Upper limits
  12. GRB 120923A: Swift-BAT refined analysis
  13. GRB 120923A: Swift/UVOT Upper Limit
  14. GRB 120923A: Gemini afterglow detection, high-z candidate
  15. GRB 120923A: Enhanced Swift-XRT position
  16. GRB 120923A: TAROT La Silla observatory optical observations
  17. GRB 120923A: ROTSE-III Optical Limits
  18. GRB 120923A: Swift detection of a burst

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