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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').

13 results found.

  1. IceCube-200425A: No significant detection in HAWC
  2. IceCube-200425A: Upper limits from a search for additional neutrino events in IceCube
  3. IceCube-200425A: Upper limits from Fermi-GBM Observations
  4. Fermi-LAT Gamma-ray Observations of IceCube-200425A
  5. IceCube-200425A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. IceCube-200425A - IceCube observation of a high-energy neutrino candidate event
  7. GRB 200425A: Swift-BAT refined analysis
  8. GRB 200425A: LCO Optical Upper Limits
  9. Swift GRB 200425A: Global MASTER-Net observations report
  10. GRB 200425A: Swift/UVOT Upper Limits
  11. GRB 200425A: Swift-XRT refined Analysis
  12. GRB 200425A: Enhanced Swift-XRT position
  13. GRB 200425A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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