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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"

31 results found.

  1. GRB 080319B: Jet Break, Energetics, Supernova
  2. GRB 070125: Chandra X-ray Confirmation of Jet Break
  3. GRB 070125: X-ray light curve analysis
  4. GRB 070125, deep late-time optical observation
  5. GRB 070125 observations with the GMRT
  6. GRB 070125: Break in Optical Decay
  7. GRB 070125 detection with CARMA
  8. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  9. GRB 070125: further AAVSO optical observations
  10. GRB 070125: optical observation
  11. GRB 070125: WSRT Radio Detection
  12. Radio detection of GRB 070125
  13. GRB 070125: confirmation of pseudo-redshift
  14. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  15. GRB 070125: further AAVSO optical observations
  16. GRB 070125: MITSuME Okayama optical observation
  17. Konus-Wind observation of GRB 070125
  18. GRB 070125: AAVSO optical observations
  19. GRB 070125: optical observations
  20. GRB 070125: PROMPT detections
  21. GRB 070125: WSRT Radio Observations
  22. GRB 070125: UVOT Detection in Ultraviolet Filters
  23. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  24. GRB 070125: Xinglong TNT optical observations
  25. GRB 070125: Continued P60 Observations
  26. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  27. GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
  28. GRB 070125: Lick 3m Spectroscopy
  29. GRB070125: Swift-XRT Refined Analysis
  30. GRB 070125: SARA detection in R
  31. GRB 070125: P60 Optical Afterglow Candidate

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Download all Circulars as a .tar.gz archive:
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