Skip to main content
New Swift-BAT/GUANO and IceCube Notice Types Available! 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').

14 results found.

  1. GRB 200925B: OSN Afterglow Candidate Discovery
  2. Fermi GRB 200906A: Global MASTER-Net observations report
  3. GRB 200906A: EMIR/GTC NIR upper limit
  4. GRB 200906A: LBT near-infrared upper limit
  5. GRB 200906A: Swift-BAT refined analysis
  6. GRB 200906A: Swift/UVOT Upper Limits
  7. GRB 200906A: GROWTH-India Telescope (GIT) optical r band upper limit
  8. GRB 200906A: OSN 1.5m Upper Limit
  9. GRB 200906A: Swift-XRT refined Analysis
  10. GRB 200906A: Fermi GBM detection
  11. GRB 200906A: Enhanced Swift-XRT position
  12. GRB 200906A: Nanshan/NEXT optical upper limit
  13. GRB 200906A: Swift detection of a burst
  14. GRB 200906A: Fermi GBM Final Real-time Localization

Advanced

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