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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"

13 results found.

  1. GRB 180512A: VLT/HAWK-I NIR Observations
  2. GRB 180512A: Swift-XRT refined Analysis
  3. GRB 180512A: Swift-BAT refined analysis
  4. GRB 180512A: RATIR Optical Observations
  5. GRB 180512A: LBT optical detection
  6. GRB 180512A: Swift/UVOT Upper Limits
  7. GRB 180512A: LT prompt observations
  8. GRB 180512A: Enhanced Swift-XRT position
  9. GRB 180512A: GROND upper limits
  10. GRB 180512A: NOT upper limits
  11. GRB 180512A: OASDG optical observations
  12. GRB 180512A: Upper limits from OSN
  13. GRB 180512A: Swift detection of a burst

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Download all Circulars as a .tar.gz archive:
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