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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').

7 results found.

  1. GRB 230827B: 10.4m GTC spectroscopic redshift
  2. GRB 230827B: Glowbug gamma-ray detection
  3. GRB 230827B: Swift-XRT afterglow detection
  4. GRB 230827B: Swift ToO observations
  5. GRB 230827B: CALET Gamma-Ray Burst Monitor detection
  6. GRB 230827B: VZLUSAT-2 detection
  7. GRB 230827B / GRB 230827256: Fermi GBM Observation


Download all Circulars as a .tar.gz archive:
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