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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. GRB 141221A: Keck spectroscopy
  2. GRB 141221A: TAROT La Silla observatory optical observations
  3. GRB 141221A: MITSuME Akeno upper limits
  4. GRB 141221A: Continued Skynet PROMPT-CTIO observations
  5. GRB 141221A: Swift/UVOT Detection
  6. GRB 141221A: Fermi GBM observation
  7. GRB 141221A: Swift-XRT refined Analysis
  8. GRB 141221A: Swift-BAT refined analysis
  9. GRB141221A: GROND Afterglow Detection
  10. GRB 141221A: Enhanced Swift-XRT position
  11. GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
  12. GRB 141221A: LCOGT-McDonald optical afterglow observations
  13. GRB 141221A: Swift detection of a burst with an optical counterpart

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