Skip to main content
Announcing GCN Classic Migration Survey, End of Legacy Circulars Email. 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').

16 results found.

  1. GRB 200306C: ALMA 3mm upper limit
  2. GRB 200306C: Swift-BAT refined analysis
  3. GRB 200306C: Swift/UVOT Detection
  4. GRB 200306C: Calar Alto 2.2m upper limit
  5. GRB 200306C: Swift-XRT refined Analysis
  6. GRB 200306C: Enhanced Swift-XRT position
  7. GRB 200306C: VIRT optical upper limits
  8. GRB 200306C: KCT upper limit of the optical afterglow
  9. GRB 200306C: LCO Optical Upper Limits
  10. GRB 200306C: OSN 1.5m afterglow detection
  11. GRB 200306C: Liverpool Telescope observations
  12. GRB 200306C: SAO RAS observations of OT
  13. GRB 200306C: GOTO upper limits
  14. GRB 200306C: BOOTES-1 detection of the optical afterglow
  15. GRB 200306C: FRAM-ORM afterglow detection
  16. GRB 200306C: Swift detection of a burst with an optical counterpart

Advanced

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