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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').

12 results found.

  1. GRB 090817 - TLS Observations
  2. GRB 090817: No host galaxy, no supernova
  3. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  4. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  5. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  6. GRB 090817: Liverpool Telescope Observations
  7. GRB 090817: optical upper limit
  8. GRB 090817: Confirmation of the X-ray afterglow
  9. GRB 090817: Fermi GBM observation
  10. GRB 090817: Swift/UVOT Upper Limits
  11. GRB 090817: Swift-XRT observations
  12. GRB 090817: a long GRB localized by INTEGRAL


Download all Circulars as a .tar.gz archive:
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