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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 220611A: Host galaxy redshift from VLT/X-shooter
  2. GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
  3. GRB 220611A: Continued Gemini Infrared Observations
  4. GRB 220611A optical counterpart
  5. GRB 220611A: Gemini Ks counterpart detection
  6. GRB 220611A: Gemini South Infrared Detection
  7. GRB 220611A: Swift/UVOT Upper Limits
  8. GRB 220611A: Swift-BAT refined analysis
  9. Swift GRB 220611A: Global MASTER-Net observations report
  10. GRB 220611A: Swift-XRT refined Analysis
  11. GRB 220611A: Enhanced Swift-XRT position
  12. GRB 220611A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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