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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18 results found.

  1. GRB 251025B: GROWTH-India Telescope continued multiband optical observations and rebrightening
  2. GRB251025B: 3.6m DOT Optical Observations
  3. GRB 251025B: Swift-XRT confirmation of fading
  4. GRB 251025B: Mondy optical observations
  5. GRB 251025B: Kilonova-Catcher optical afterglow detection
  6. GRB 251025B: VLT/MUSE spectroscopic redshift z = 2.003
  7. GRB 251025B: MAO/AZT-22 optical observations
  8. GRB 251025B: OHP/T193 optical detection
  9. GRB 251025B: J-band detection with WINTER
  10. GRB 251025B: SVOM/VT optical bump
  11. GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
  12. GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
  13. GRB 251025B: GROWTH-India Telescope optical observations
  14. GRB 251025B: Swift-XRT afterglow detection
  15. GRB 251025B: SVOM/VT optical observations with VHF data
  16. GRB 251025B: MASTER OT detection
  17. GRB 251025B: SVOM/C-GFT optical counterpart detection
  18. GRB 251025B: SVOM detection of a burst

Advanced

Download all Circulars as a .tar.gz archive:
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