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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"

20 results found.

  1. GRB 251202A: further radio observations with the VLA
  2. GRB 251202A/EP251202a: Koshka optical upper limit
  3. GRB 251202A: radio detection with the VLA
  4. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  5. GRB 251202A: SVOM/GRM observation
  6. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  7. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  8. EP251202a / GRB251202A: AstroSat CZTI detection
  9. GRB 251202A / EP251202a: SVOM/VT optical observation
  10. EP251202a/GRB 251202A: KAIT optical observations
  11. GRB 251202A: Fermi GBM Observation
  12. GRB 251202A: Swift/UVOT Detection
  13. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  14. GRB 251202A: GOTO optical afterglow detection
  15. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  16. GRB 251202A: Swift-XRT afterglow detection
  17. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  18. Fermi GRB 251202A: Global MASTER-Net observations report
  19. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  20. GRB 251202A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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