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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').

12 results found.

  1. GRB 100420A: EVLA radio observations
  2. GRB 100420A: Gemini discovery of infrared afterglow
  3. GRB 100420A: Terskol optical upper limit
  4. GRB 100420A: GRT Optical Observation
  5. GRB 100420A: Swift-BAT refined analysis
  6. GRB100420A: MITSuME optical upper limits
  7. GRB 100420A: Swift/UVOT Upper Limits
  8. GRB 100420A: XRT refined analysis
  9. GRB 100420A: Enhanced Swift-XRT position
  10. GRB 100420A: SARA Upper Limits
  11. GRB 100420A: ROTSE-III Optical Limits
  12. GRB 100420A: Swift detection of a burst

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