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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').

12 results found.

  1. GRB 171222A: Swift-BAT refined analysis
  2. GRB 171222A: AROMA-N optical observation
  3. GRB 171222A: Fermi GBM detection
  4. GRB 171222A: Nanshan-0.36m optical upper limit
  5. GRB 171222A: Swift/UVOT Upper Limits
  6. GRB 171222A: Nanshan-1m optical afterglow detection
  7. GRB 171222A: MASTER-Net OT observations
  8. GRB 171222A: Redshift from 10.4m GTC/OSIRIS
  9. GRB 171222A: Swift-XRT refined Analysis
  10. GRB 171222A: NOT Optical Afterglow
  11. GRB 171222A: Enhanced Swift-XRT position
  12. GRB 171222A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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