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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 251013C: Leavitt Observatory optical photometry
  2. GRB 250925A: Leavitt Observatory optical upper limit
  3. GRB 250702F: Leavitt Observatory optical observations
  4. GRB 250625A: Leavitt Observatory afterglow detection
  5. GRB 250430A: Leavitt Observatory optical upper limit
  6. GRB 250404A / EP250404a: Leavitt Observatory optical counterpart detection
  7. GRB 250317B: Leavitt Observatory optical upper limit
  8. GRB 250205A: Leavitt Observatory optical upper limit
  9. EP241217a : Leavitt Observatory optical upper limit
  10. GRB 240929A : Leavitt Observatory optical upper limit
  11. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  12. EP240801a: Leavitt Observatory optical observations
  13. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  14. GRB 231111A: Leavitt Observatory optical observations
  15. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  16. GRB 230818A: Leavitt Observatory upper limit
  17. GRB 230812B: Leavitt Observatory optical observations
  18. GRB 230723B: Leavitt Observatory upper limit

Advanced

Download all Circulars as a .tar.gz archive:
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