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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').

17 results found.

  1. GRB 200227A: RATIR Optical Observations
  2. IceCube-200227A: Upper limits from a search for additional neutrino events in IceCube
  3. GRB 200227A: Mondy optical upper limit
  4. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  5. GRB 200227A: Insight-HXMT/HE detection
  6. IceCube-200227A : Upper limits from Insight-HXMT/HE observations
  7. GRB 200227A: Swift-XRT refined Analysis
  8. GRB 200227A: Swift-BAT refined analysis
  9. GRB 200227A: Swift/UVOT Upper Limits
  10. GRB 200227A: Enhanced Swift-XRT position
  11. IceCube-200227A: Upper limits from Fermi-GBM Observations
  12. GRB 200227A: Fermi GBM observation
  13. IceCube-200227A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  14. GRB 200227A: MITSuME Akeno optical upper limit
  15. IceCube-200227A: IceCube observation of a high-energy neutrino candidate event
  16. GRB 200227A: Swift detection of a burst
  17. GRB 200227A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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