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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').

14 results found.

  1. GRB 171020A: Continued RATIR Optical and NIR Observation
  2. GRB 171020A: TAROT Calern observatory optical observations
  3. GRB 171020A: Swift/UVOT Upper Limits
  4. GRB 171020A: NOT spectroscopic redshift
  5. GRB 171020A: Swift-BAT refined analysis
  6. GRB 171020A: RATIR Optical and NIR Observations
  7. GRB 171020A: Swift-XRT refined Analysis
  8. GRB 171020A: Enhanced Swift-XRT position
  9. GRB 171020A: LT observations
  10. GRB 171020A: Correction of alpha in GCN 22031
  11. GRB 171020A: Confirmation of OT fading
  12. GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission
  13. GRB 171020A: NOT optical afterglow detection
  14. GRB 171020A: Swift detection of a burst

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