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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"

36 results found.

  1. GRB 050408: ARC 3.5-meter NIR Observations
  2. GRB 050408: jet break in the XRT light curve
  3. GRB 050408: RTT150 optical observations
  4. GRB 050408: Kuiper 1.5m observations
  5. GRB 050408: refined XRT analysis, no jet break seen yet
  6. GRB 050408: SDSS Field Calibration
  7. GRB 050408: Optical limit
  8. GRB 050408: PROMPT VRcIc Observations
  9. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  10. GRB 050408: Swift XRT measurement of possible jet break
  11. GRB 050408: Retraction of Proposed Host Galaxy
  12. GRB 050408: Inconsistency of host galaxy identification
  13. GRB 050408: Subaru Observations
  14. GRB 050408: WIDGET simultaneous optical observations
  15. GRB 050408: SOAR UBVRc Observations
  16. GRB 050408: Properties of the Host Galaxy
  17. GRB 050408: Mercator Optical Observations
  18. GRB 050408: Swift XRT analysis
  19. GRB 050408, SMARTS optical/IR afterglow observations
  20. GRB 050408: Optical limit at 20 min after the burst
  21. GRB 050408, optical observations
  22. GRB 050408: Moderate-resolution Gemini Spectroscopy
  23. GRB 050408,optical observation
  24. GRB 050408 Optical Observations
  25. GRB 050408: Emission and absorption redshift
  26. GRB 050408: Mercator Optical Observations
  27. GRB 050408: Magellan astrometry and photometry
  28. GRB 050408: First Optical observations with TFOSC at the RTT150
  29. GRB 050408: steepening of the optical decay
  30. GRB 050408: Optical afterglow confirmed
  31. GRB 050408: opitcal observation
  32. GRB 050408, optical observations
  33. GRB 050408 optical candidate
  34. GRB 050408: Swift XRT Position
  35. GRB 050408: ROTSE-III Optical Limits
  36. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE

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