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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').

15 results found.

  1. GRB 070521: pseudo-z ~ 2.28 from prompt emission spectrum
  2. Konus-Wind observation of GRB 070521
  3. GRB 070521: Swift/UVOT Upper Limits
  4. GRB 070521, optical observation
  5. GRB 070521: Swift-XRT refined analysis
  6. GRB 070521: Keck imaging
  7. GROND upper limits of GRB 070521
  8. GRB 070521 Milagro GeV/TeV Observations
  9. GRB 070521: SARA upper limit
  10. GRB 070521: Subaru observations and possible host detection
  11. GRB 070521, Swift-BAT refined analysis
  12. GRB 070521: optical limit by Pi of the Sky
  13. GRB 070521: TAROT La Silla observatory optical observations
  14. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  15. GRB 070521: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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