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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').

7 results found.

  1. GRB 230123A: LCOGT Optical Upper Limits
  2. GRB 230123A: Swift-BAT refined analysis
  3. GRB 230123A: Swift/UVOT Upper Limits
  4. GRB 230123A: Swift-XRT refined Analysis
  5. GRB 230123A: Enhanced Swift-XRT position
  6. GRB 230123A: Zadko observatory - Gingin optical observations
  7. GRB 230123A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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