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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 150222A: CrAO optical observation
  2. GRB 150222A: Further GROND Observations
  3. GRB 150222A: I-band observations from OSN
  4. GRB 150222A: Swift/UVOT Upper Limits
  5. GRB 150222A: Swift-XRT refined Analysis
  6. GRB 150222A: GROND optical afterglow candidate
  7. GRB 150222A: Enhanced Swift-XRT position
  8. GRB 150222A: TNG optical observations
  9. GRB 150222A: Swift-BAT refined analysis
  10. GRB 150222A: Mondy optical observations
  11. GRB 150222A: Zadko observatory - Gingin optical observations
  12. GRB 150222A: MASTER early optical observations
  13. GRB 150222A: Swift detection of a burst


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