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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.

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

35259 results found.

  1. GRB010222: Optical Observations
  2. GRB010222, optical observations
  3. GRB010222: BeppoSAX/NFI Observations
  4. Redshift of the Optical Transient of GRB010222
  5. GRB010214B,Gamma Ray Observations
  6. GRB010222
  7. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  8. GRB 010220, simultaneous optical observations
  9. GRB010220: BeppoSAX WFC and GRBM preliminary data
  10. BeppoSAX ALERT: GRB010220
  11. GRB010214: BeppoSAX WFC and GRBM preliminary data
  12. GRB 010214: X-Ray afterglow
  13. GRB 010214, Optical Observations
  14. GRB 010214 optical observation
  15. GRB010213 Optical Observation
  16. J-Band Observation of GRB 010214.
  17. GRB010213, Near-IR observations
  18. Possible InfraRed Transient of GRB 010214.
  19. GRB010214 Optical Observation
  20. GRB010214: BeppoSAX/NFI Observations
  21. GRB010213 (HETE) TAROT observations
  22. GRB 010214, optical observations
  23. BeppoSAX ALERT: GRB010214
  24. IPN Status Report
  25. HETE Status
  26. GRB010126 opt. obs.
  27. IPN/RXTE TRIANGULATION OF GRB010126
  28. GRB010126: CONCAM crude optical limits during GRB
  29. GRB010126, TNG R-band observations
  30. IPN TRIANGULATION OF GRB010126
  31. IPN/RXTE TRIANGULATION OF GRB010126
  32. GRB 010119, optical observations
  33. GRB010119: Optical observations
  34. Optical Observations of GRB 001018 at Keck
  35. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  36. Optical observations of GRB 001018 with JCAM
  37. IPN TRIANGULATION OF GRB010115
  38. IPN TRIANGULATION OF GRB010109
  39. GRB010103, optical observations
  40. IPN triangulation of GRB010104
  41. IPN triangulation of GRB010103
  42. GRB 001204: Ks observations
  43. H band observation of GRB 001212
  44. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  45. IPN triangulation of GRB001219
  46. GRB 001212 Optical Observation
  47. GRB 001212 Optical Observation
  48. GRB 001212 optical observation
  49. GRB 001212 possible OA in 2MASS
  50. GRB 001212 possible OA
  51. IPN triangulation of GRB001212
  52. Confirmation of IPN position for GRB001204
  53. IPN triangulation of GRB001204 (short/hard)
  54. GRB 001105, further optical observations
  55. GRB001120: Gunn-i observations
  56. GRB001120: Optical observations
  57. GRB001109, optical observations
  58. GRB001120, optical observations
  59. IPN triangulation of GRB001120
  60. Optical/NIR observations of GRB001109
  61. GRB 001109: deep JHK upper limits
  62. GRB 001109 X-ray afterglow with BeppoSAX
  63. GRB001109: Optical observations
  64. GRB001109: BeppoSAX/NFI Observations
  65. GRB001109, R-band optical observations
  66. GRB001109, Radio observations
  67. BeppoSAX ALERT: GRB001109
  68. GRB001105 BVRI field photometry correction
  69. GRB001105, BVRI field photometry
  70. GRB 001105, R-band observation
  71. IPN TRIANGULATION OF GRB001105
  72. GRB 001025B, Optical obervations
  73. GRB 991208: HST Imaging of the Host Galaxy
  74. GRB000926: R-image of the host galaxy
  75. GRB 001025B, I-band observations
  76. GRB 001025 Optical Observations
  77. GRB 001025A, optical observation
  78. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  79. IPN triangulation of GRB001025
  80. ASM Localization of GRB 001025
  81. GRB001007, Radio observations
  82. IPN TRIANGULATION OF GRB001020
  83. GRB001019, Optical Observations
  84. GRB 001018, Possible Radio Afterglow
  85. GRB001018, Gamma Ray Observations
  86. IPN TRIANGULATION OF GRB001019
  87. IPN TRIANGULATION OF GRB001018
  88. IPN TRIANGULATION OF GRB 001017
  89. GRB 000926: Improved Absorber Redshift
  90. V,R,I band observations of GRB000926
  91. The Likely Optical/Infrared Afterglow of GRB 001011
  92. HETE positions added to GCN
  93. BeppoSAX ALERT: GRB001011
  94. GRB 001007, BVR-band observations
  95. GRB000926 - Amateur Optical Observations
  96. CONCAM null result on GRB001005
  97. IPN triangulation of GRB001007
  98. GRB 000926 : the host galaxy
  99. IPN triangulation of GRB001005
  100. GRB 000926 Chandra Observation

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