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').

9 results found.

  1. Corrections to the Fermi-LAT upper limits for GRB 120807A, 120908A, 120909A, and 120911A
  2. GRB 120807A: Swift/UVOT Upper Limits
  3. GRB 120807A: Swift-XRT refined Analysis
  4. GRB 120807A: Fermi/LAT upper limit
  5. GRB 120807A: RAPTOR Limits During Gamma-Ray Emitting Interval
  6. GRB 120807A: TAROT La Silla observatory optical observations
  7. GRB 120807A: Swift-BAT refined analysis
  8. GRB 120807A: Enhanced Swift-XRT position
  9. GRB 120807A: 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