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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').

9 results found.

  1. GRB 220427A: MeerLICHT afterglow observations
  2. GRB 220427A: LCO Optical Observations
  3. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  4. GRB 220427A: Swift-BAT refined analysis
  5. GRB 220427A: VLT/X-shooter photometry
  6. Konus-Wind detection of GRB 220427A
  7. GRB 220427A: Swift-XRT refined Analysis
  8. GRB 220427A: Enhanced Swift-XRT position
  9. GRB 220427A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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