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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

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

19662 results found.

  1. GRB050128 Swift-BAT observations
  2. GRB 050128: Swift XRT prompt afterglow position
  3. GRB 050124: K-band afterglow observations
  4. GRB050126: MASTER optical limit for KECK OT
  5. GRB050126: Burst Parameters Measured by BAT
  6. GRB050126: MASTER optical observations
  7. GRB 050126: Prompt XRT detection and localization
  8. GRB050124: No Swift UVOT Detection of Afterglow Emission
  9. GRB 050117a: Radio Observations
  10. GRB050124,optical observation
  11. GRB050124: Updated Swift XRT Position and Fluxes
  12. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  13. GRB050124: Refined BAT position, spectral and fluence information
  14. GRB050124: Swift-BAT position of a double-peaked burst
  15. GRB050117a: Radio Observations
  16. GRB050117a: Refined analysis
  17. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  18. GRB050117b: Swift-BAT detection of a weak burst
  19. GRB050117: optical observation
  20. GRB 050117, I-band observations
  21. GRB 050117: Optical observation
  22. GRB050117: Refined XRT position
  23. GRB050117: MASTER optical observations
  24. MASTER:GRB050117 SWIFT
  25. GRB050117: Swift-BAT detection of a long multi-peaked burst
  26. GRB050117: Swift XRT Position
  27. SGR1806-20: Swift-BAT observations of two additional bursts
  28. SGR 1806-20, RHESSI observations of the 041227 giant flare
  29. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  30. GRB 041217: Optical observations
  31. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  32. GRB041228: ROTSE-III Optical Observations
  33. GRB041228: Swift-BAT detection of a burst
  34. GRB041219; RXTE ASM Observations
  35. NIR Observations of GRB 041219
  36. GRB041226: ROTSE-III Optical Observations
  37. GRB041226: Swift-BAT detection of a burst
  38. GRB041223: decay of the afterglow
  39. GRB041224: ROTSE-III Optical Observations
  40. GRB 041223: XRT afterglow spectrum and light curve
  41. GRB 041223 Fluence measured by Swift-BAT
  42. GRB041224: Swift-BAT detection of a soft burst
  43. GRB041223: optical and NIR observations with REM
  44. Swift-BAT Time History of GRB041219
  45. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  46. GRB041223: ROTSE-III Optical Observations
  47. GRB041223: Swift-BAT detection of a bright long burst
  48. GRB041220: Swift-BAT burst
  49. GRB 041219 Optical Observations
  50. GRB041219c: Third Burst in One Day from Swift-BAT
  51. GRB041219b: A Swift-BAT burst
  52. Swift-BAT detection of the bright long burst GRB041219
  53. GRB041217: optical limit 30 min after GRB
  54. GRB041217: Optical Observations
  55. GRB041217: NIR and optical observations with REM
  56. GRB041217: P60 Optical Observations
  57. GRB041217: Infrared Observations
  58. GRB041217: The First GRB Located On-Board Swift
  59. GRB040916: Optical observations
  60. GRB040422: optical and NIR observations at the VLT
  61. GRB040223, improved XMM position
  62. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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