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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').

10 results found.

  1. GRB 090518: Skynet/PROMPT Observations
  2. GRB 090518 - NOT upper limit
  3. GRB 090518: Fermi GBM detection
  4. GRB 090518: Swift/UVOT Upper Limits
  5. GRB090518: GROND upper limits
  6. GRB 090518: P60 Observations
  7. GRB 090518, Swift-BAT refined analysis
  8. GRB 090518: Swift-XRT refined analysis
  9. GRB 090518: Enhanced Swift-XRT position
  10. GRB 090518: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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