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').

13 results found.

  1. GRB 200512A: Swift-BAT refined analysis
  2. GRB 200512A: LCO Optical Upper Limits
  3. IceCube-200512A: Upper limits from a search for additional neutrino events in IceCube
  4. Fermi GBM Sub-Threshold Detection of GRB 200512A
  5. GRB 200512A: Swift/UVOT Upper Limits
  6. GRB 200512A: Swift-XRT refined Analysis
  7. GRB 200512A: Enhanced Swift-XRT position
  8. GRB 200512A: Swift detection of a burst
  9. Fermi-LAT Gamma-ray Observations of IceCube-200512A
  10. IceCube-200512A: not observable by Fermi-GBM
  11. IceCube-200512A: No Candidate Counterparts from the Zwicky Transient Facility
  12. IceCube-200512A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  13. IceCube-200512A: IceCube observation of a high-energy neutrino candidate event

Advanced

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