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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').

9 results found.

  1. GRB 150323B: Swift-XRT afterglow detection
  2. GRB 150323B: Khureltogot optical observations
  3. GRB 150323B; Konkoly optical observations
  4. Konus-Wind observation of GRB 150323B
  5. GRB 150323B : Xinglong TNT upper limit
  6. GRB 150323B: Swift-XRT observations
  7. GRB 150323B: Fermi GBM observation
  8. GRB 150323B: Swift ToO observations
  9. GRB 150323B detected in ground analysis of Swift-BAT data


Download all Circulars as a .tar.gz archive:
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