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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"

14 results found.

  1. GRB 230414B: Nickel and KAIT telescope optical observations
  2. GRB 230414B Swift-BAT refined analysis
  3. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  4. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  5. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  6. GRB 230414B: Lulin 40cm-SLT optical limit
  7. GRB 230414B: Bassano Bresciano Observatory optical observations
  8. GRB 230414B: Redshift from OSIRIS/GTC
  9. GRB 230414B: Swift-XRT refined Analysis
  10. GRB 230414B: Dabancheng/GHOST optical observations
  11. GRB 230414B (correction GRB name in the GCN 33615): Mondy optical afterglow candidate
  12. GRB 230414B: Nanshan/HMT optical afterglow detection
  13. Swift GRB 230414B: Global MASTER-Net observations report
  14. GRB 230414B: Prompt enhanced Swift-XRT position

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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