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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.

Lucene Examples (click to copy):

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

6 results found.

  1. GRB 160530A: further Swift-XRT follow-up observations
  2. GRB 160530A: Swift follow-up and X-ray afterglow candidate
  3. Konus-Wind observation of GRB 160530A
  4. IPN Triangulation of GRB 160530A
  5. GRB 160530A: discovery with the Compton Spectrometer and Imager
  6. GRB 160530A: Tiled Swift observations

Advanced

Download all Circulars as a .tar.gz archive:
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