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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 090927: Fermi GBM observation
  2. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  3. GRB 090927: VLT redshift
  4. GRB 090927: Zadko Telescope observations
  5. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  6. Swift/UVOT observations of GRB 090927
  7. GRB 090927: Swift XRT refined analysis
  8. GRB 090927: Enhanced Swift-XRT position
  9. GRB 090927: Swift/UVOT detection of an optical afterglow
  10. GRB 090927: Swift detection of a short burst

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Download all Circulars as a .tar.gz archive:
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