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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').
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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"

36077 results found.

  1. GRB010222, possible increase of optical decay slope
  2. GRB 010222 Kyoto optical observation
  3. GRB010222: fading behavior
  4. GRB 010222 BV optical observations
  5. GRB 010220: Near-IR Observations
  6. GRB010214 follow-up from Hanle
  7. GRB 010222: Near-IR Observations
  8. GRB 010222: Optical Observations
  9. GRB 010222, Decay Slope Confirmed
  10. GRB010222: Another absorption line system
  11. GRB010222: Optical decay slope
  12. GRB 010214, Optical Observations
  13. GRB010222: Sub-millimeter detection
  14. GRB010222: R-band fading behavior
  15. GRB010222: Optical Observations
  16. GRB010222, optical observations
  17. GRB010222: BeppoSAX/NFI Observations
  18. Redshift of the Optical Transient of GRB010222
  19. GRB010214B,Gamma Ray Observations
  20. GRB010222
  21. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  22. GRB 010220, simultaneous optical observations
  23. GRB010220: BeppoSAX WFC and GRBM preliminary data
  24. BeppoSAX ALERT: GRB010220
  25. GRB010214: BeppoSAX WFC and GRBM preliminary data
  26. GRB 010214: X-Ray afterglow
  27. GRB 010214, Optical Observations
  28. GRB 010214 optical observation
  29. GRB010213 Optical Observation
  30. J-Band Observation of GRB 010214.
  31. GRB010213, Near-IR observations
  32. Possible InfraRed Transient of GRB 010214.
  33. GRB010214 Optical Observation
  34. GRB010214: BeppoSAX/NFI Observations
  35. GRB010213 (HETE) TAROT observations
  36. GRB 010214, optical observations
  37. BeppoSAX ALERT: GRB010214
  38. IPN Status Report
  39. HETE Status
  40. GRB010126 opt. obs.
  41. IPN/RXTE TRIANGULATION OF GRB010126
  42. GRB010126: CONCAM crude optical limits during GRB
  43. GRB010126, TNG R-band observations
  44. IPN TRIANGULATION OF GRB010126
  45. IPN/RXTE TRIANGULATION OF GRB010126
  46. GRB 010119, optical observations
  47. GRB010119: Optical observations
  48. Optical Observations of GRB 001018 at Keck
  49. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  50. Optical observations of GRB 001018 with JCAM
  51. IPN TRIANGULATION OF GRB010115
  52. IPN TRIANGULATION OF GRB010109
  53. GRB010103, optical observations
  54. IPN triangulation of GRB010104
  55. IPN triangulation of GRB010103
  56. GRB 001204: Ks observations
  57. H band observation of GRB 001212
  58. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  59. IPN triangulation of GRB001219
  60. GRB 001212 Optical Observation
  61. GRB 001212 Optical Observation
  62. GRB 001212 optical observation
  63. GRB 001212 possible OA in 2MASS
  64. GRB 001212 possible OA
  65. IPN triangulation of GRB001212
  66. Confirmation of IPN position for GRB001204
  67. IPN triangulation of GRB001204 (short/hard)
  68. GRB 001105, further optical observations
  69. GRB001120: Gunn-i observations
  70. GRB001120: Optical observations
  71. GRB001109, optical observations
  72. GRB001120, optical observations
  73. IPN triangulation of GRB001120
  74. Optical/NIR observations of GRB001109
  75. GRB 001109: deep JHK upper limits
  76. GRB 001109 X-ray afterglow with BeppoSAX
  77. GRB001109: Optical observations
  78. GRB001109: BeppoSAX/NFI Observations
  79. GRB001109, R-band optical observations
  80. GRB001109, Radio observations
  81. BeppoSAX ALERT: GRB001109
  82. GRB001105 BVRI field photometry correction
  83. GRB001105, BVRI field photometry
  84. GRB 001105, R-band observation
  85. IPN TRIANGULATION OF GRB001105
  86. GRB 001025B, Optical obervations
  87. GRB 991208: HST Imaging of the Host Galaxy
  88. GRB000926: R-image of the host galaxy
  89. GRB 001025B, I-band observations
  90. GRB 001025 Optical Observations
  91. GRB 001025A, optical observation
  92. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  93. IPN triangulation of GRB001025
  94. ASM Localization of GRB 001025
  95. GRB001007, Radio observations
  96. IPN TRIANGULATION OF GRB001020
  97. GRB001019, Optical Observations
  98. GRB 001018, Possible Radio Afterglow
  99. GRB001018, Gamma Ray Observations
  100. IPN TRIANGULATION OF GRB001019

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