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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').

11 results found.

  1. GRB 130327A: RATIR Optical/NIR afterglow confirmation
  2. GRB 130327A: Swift-BAT refined analysis
  3. GRB 130327A: Gemini Observations
  4. GRB 130327A: Swift-XRT refined Analysis
  5. GRB 130327A: Weihai optical obsevations
  6. GRB 130327A: Swift/UVOT Upper Limits
  7. GRB 130327A: ISON-NM optical upper limit
  8. GRB 130327A: Enhanced Swift-XRT position
  9. GRB 130327A: RATIR Optical and NIR Observations
  10. GRB 130327A: PAIRITEL NIR Afterglow Candidate
  11. GRB 130327A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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