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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').

13 results found.

  1. Corrections to the Fermi-LAT upper limits for GRB 120807A, 120908A, 120909A, and 120911A
  2. GRB 120908A and GRB 120909A : Fermi/LAT upper limit
  3. GRB 120909A: TAROT La Silla observatory optical observations
  4. GRB 120909A: Pi of the Sky upper limits
  5. GRB 120909A: Fermi GBM observation
  6. Konus-Wind observation of GRB 120909A
  7. GRB 120909A: Swift/UVOT Detection
  8. GRB 120909A: Swift-XRT refined Analysis
  9. GRB 120909A: Swift-BAT refined analysis
  10. GRB 120909A: Enhanced Swift-XRT position
  11. GRB 120909A: X-Shooter redshift 3.93
  12. GRB 120909A: GROND detection of the afterglow
  13. GRB 120909A: Swift detection of a burst

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