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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. Fwd: GRB 091003: Possible Supernova Component Retraction
  2. GRB 091003: Possible Supernova Component
  3. GRB 091003: Gemini-N redshift of possible host galaxy
  4. GRB 091003: Lick observations and possible SDSS host galaxy
  5. GRB 091003: WHT ACAM observations
  6. GRB 091003: Swift-XRT confirmation of fading afterglow
  7. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  8. GRB 091003: Skynet/DSO Observations
  9. GRB 091003: UVOT-enhanced XRT position
  10. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  11. GRB 091003: Swift XRT analysis
  12. GRB 091003A: Fermi LAT detection


Download all Circulars as a .tar.gz archive:
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