Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

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 220701A: Swift-BAT refined analysis
  2. GRB 220701A: MITSuME Akeno optical upper limits
  3. GRB 220701A: COATLI Optical Upper Limit
  4. GRB 220701A: AbAO optical upper limit
  5. GRB 220701A: Keck/LRIS Optical Upper Limit
  6. GRB 220701A: Swift-XRT refined Analysis
  7. GRB 220701A: LCO Optical Upper Limits
  8. GRB 220701A: BOOTES-5/JGT early optical upper limit
  9. GRB 220701A: Swift/UVOT Upper Limits
  10. GRB 220701A: Lowell Discovery Telescope Optical Observations
  11. GRB 220701A: Enhanced Swift-XRT position
  12. GRB 220701A: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive:
Looking for U.S. government information and services? Visit USA.gov