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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').

113 results found.

  1. GRB 221009A: Swift-XRT refined Analysis
  2. GRB 221009A (Swift J1913.1+1946): AGILE/MCAL detection
  3. GRB 221009A: Redshift from X-shooter/VLT
  4. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  5. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  6. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  7. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  8. GRB 221009A: Fermi GBM observation
  9. IPN triangulation of extremely bright GRB 221009A
  10. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  11. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  12. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  13. GRB 221009A: Swift detected transient may be GRB

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