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').

16 results found.

  1. Subject : GRB 121209A: LOAO Observation
  2. GRB 121209A: Swift/UVOT Upper Limits
  3. GRB 121209A: MAXI/GSC detection
  4. GRB 121209A: Early CARMA Observations
  5. GRB 121209A: Keck observations
  6. GRB 121209A: CARMA 3mm Observations
  7. GRB 121209A: EVLA Observations
  8. GRB 121209A: Swift-XRT refined Analysis
  9. GRB 121209A: Swift-BAT refined analysis
  10. GRB 121209A: Enhanced Swift-XRT position
  11. GRB121209A: RATIR Optical and NIR Upper Limits
  12. GRB 121209A: GROND optical afterglow candidate
  13. GRB 121209A: Gemini-South imaging
  14. GRB 121209A: PAIRITEL NIR Observations
  15. GRB 121209A: UVOT Observation
  16. GRB 121209A: 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