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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').

17167 results found.

  1. GRB050128,optical observations
  2. GRB050126: Updated Swift XRT Position
  3. GRB 050126: Radio Observations
  4. GRB050128 Swift-BAT observations
  5. GRB 050128: Swift XRT prompt afterglow position
  6. GRB 050124: K-band afterglow observations
  7. GRB050126: MASTER optical limit for KECK OT
  8. GRB050126: Burst Parameters Measured by BAT
  9. GRB050126: MASTER optical observations
  10. GRB 050126: Prompt XRT detection and localization
  11. GRB050124: No Swift UVOT Detection of Afterglow Emission
  12. GRB 050117a: Radio Observations
  13. GRB050124,optical observation
  14. GRB050124: Updated Swift XRT Position and Fluxes
  15. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  16. GRB050124: Refined BAT position, spectral and fluence information
  17. GRB050124: Swift-BAT position of a double-peaked burst
  18. GRB050117a: Radio Observations
  19. GRB050117a: Refined analysis
  20. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  21. GRB050117b: Swift-BAT detection of a weak burst
  22. GRB050117: optical observation
  23. GRB 050117, I-band observations
  24. GRB 050117: Optical observation
  25. GRB050117: Refined XRT position
  26. GRB050117: MASTER optical observations
  27. MASTER:GRB050117 SWIFT
  28. GRB050117: Swift-BAT detection of a long multi-peaked burst
  29. GRB050117: Swift XRT Position
  30. SGR1806-20: Swift-BAT observations of two additional bursts
  31. SGR 1806-20, RHESSI observations of the 041227 giant flare
  32. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  33. GRB 041217: Optical observations
  34. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  35. GRB041228: ROTSE-III Optical Observations
  36. GRB041228: Swift-BAT detection of a burst
  37. GRB041219; RXTE ASM Observations
  38. NIR Observations of GRB 041219
  39. GRB041226: ROTSE-III Optical Observations
  40. GRB041226: Swift-BAT detection of a burst
  41. GRB041223: decay of the afterglow
  42. GRB041224: ROTSE-III Optical Observations
  43. GRB 041223: XRT afterglow spectrum and light curve
  44. GRB 041223 Fluence measured by Swift-BAT
  45. GRB041224: Swift-BAT detection of a soft burst
  46. GRB041223: optical and NIR observations with REM
  47. Swift-BAT Time History of GRB041219
  48. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  49. GRB041223: ROTSE-III Optical Observations
  50. GRB041223: Swift-BAT detection of a bright long burst
  51. GRB041220: Swift-BAT burst
  52. GRB 041219 Optical Observations
  53. GRB041219c: Third Burst in One Day from Swift-BAT
  54. GRB041219b: A Swift-BAT burst
  55. Swift-BAT detection of the bright long burst GRB041219
  56. GRB041217: optical limit 30 min after GRB
  57. GRB041217: Optical Observations
  58. GRB041217: NIR and optical observations with REM
  59. GRB041217: P60 Optical Observations
  60. GRB041217: Infrared Observations
  61. GRB041217: The First GRB Located On-Board Swift
  62. GRB040916: Optical observations
  63. GRB040422: optical and NIR observations at the VLT
  64. GRB040223, improved XMM position
  65. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  66. GRB 021004: VRI observations at TNG: possible break
  67. GRB 021004: WC wind?

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