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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"

22 results found.

  1. GRB161004A: Further analysis of the burst nature
  2. GRB 100816A: Fermi GBM observation (correction to GCN 11124)
  3. Konus-Wind observation of GRB 100816A
  4. GRB100816A: MITSuME optical upper limits
  5. GRB 100816A: 10.4-m GTC redshift confirmation
  6. GRB 100816A: Fermi GBM observation
  7. GRB 100816A: VLT and Gemini-N revised redshift
  8. GRB 100816A: NOT optical observations
  9. GRB 100816A : Lulin r'-band observation
  10. GRB 100816A: Gemini-N spectroscopy
  11. GRB 100816A: Swift UVOT Observations
  12. GRB100816A Swift-XRT refined analysis
  13. GRB 100816A: Swift-BAT spectral lag results
  14. GRB 100816A: 1.23m CAHA optical observations
  15. GRB 100816A, Swift-BAT refined analysis
  16. GRB 100816A: Enhanced Swift-XRT position
  17. GRB 100816A: Gemini-N imaging
  18. GRB 100816A: CQUEAN riz-band Detection, Host Galaxy?
  19. GRB 100816A: TAROT Calern observatory optical detection
  20. GRB 100816A: MASTER Optical Limits
  21. GRB 100816A: ROTSE-III Optical Limits
  22. GRB 100816A: Swift detection of a possibly short burst with optical afterglow

Advanced

Download all Circulars as a .tar.gz archive:
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