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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"

35253 results found.

  1. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  2. GRB 010220, simultaneous optical observations
  3. GRB010220: BeppoSAX WFC and GRBM preliminary data
  4. BeppoSAX ALERT: GRB010220
  5. GRB010214: BeppoSAX WFC and GRBM preliminary data
  6. GRB 010214: X-Ray afterglow
  7. GRB 010214, Optical Observations
  8. GRB 010214 optical observation
  9. GRB010213 Optical Observation
  10. J-Band Observation of GRB 010214.
  11. GRB010213, Near-IR observations
  12. Possible InfraRed Transient of GRB 010214.
  13. GRB010214 Optical Observation
  14. GRB010214: BeppoSAX/NFI Observations
  15. GRB010213 (HETE) TAROT observations
  16. GRB 010214, optical observations
  17. BeppoSAX ALERT: GRB010214
  18. IPN Status Report
  19. HETE Status
  20. GRB010126 opt. obs.
  21. IPN/RXTE TRIANGULATION OF GRB010126
  22. GRB010126: CONCAM crude optical limits during GRB
  23. GRB010126, TNG R-band observations
  24. IPN TRIANGULATION OF GRB010126
  25. IPN/RXTE TRIANGULATION OF GRB010126
  26. GRB 010119, optical observations
  27. GRB010119: Optical observations
  28. Optical Observations of GRB 001018 at Keck
  29. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  30. Optical observations of GRB 001018 with JCAM
  31. IPN TRIANGULATION OF GRB010115
  32. IPN TRIANGULATION OF GRB010109
  33. GRB010103, optical observations
  34. IPN triangulation of GRB010104
  35. IPN triangulation of GRB010103
  36. GRB 001204: Ks observations
  37. H band observation of GRB 001212
  38. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  39. IPN triangulation of GRB001219
  40. GRB 001212 Optical Observation
  41. GRB 001212 Optical Observation
  42. GRB 001212 optical observation
  43. GRB 001212 possible OA in 2MASS
  44. GRB 001212 possible OA
  45. IPN triangulation of GRB001212
  46. Confirmation of IPN position for GRB001204
  47. IPN triangulation of GRB001204 (short/hard)
  48. GRB 001105, further optical observations
  49. GRB001120: Gunn-i observations
  50. GRB001120: Optical observations
  51. GRB001109, optical observations
  52. GRB001120, optical observations
  53. IPN triangulation of GRB001120
  54. Optical/NIR observations of GRB001109
  55. GRB 001109: deep JHK upper limits
  56. GRB 001109 X-ray afterglow with BeppoSAX
  57. GRB001109: Optical observations
  58. GRB001109: BeppoSAX/NFI Observations
  59. GRB001109, R-band optical observations
  60. GRB001109, Radio observations
  61. BeppoSAX ALERT: GRB001109
  62. GRB001105 BVRI field photometry correction
  63. GRB001105, BVRI field photometry
  64. GRB 001105, R-band observation
  65. IPN TRIANGULATION OF GRB001105
  66. GRB 001025B, Optical obervations
  67. GRB 991208: HST Imaging of the Host Galaxy
  68. GRB000926: R-image of the host galaxy
  69. GRB 001025B, I-band observations
  70. GRB 001025 Optical Observations
  71. GRB 001025A, optical observation
  72. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  73. IPN triangulation of GRB001025
  74. ASM Localization of GRB 001025
  75. GRB001007, Radio observations
  76. IPN TRIANGULATION OF GRB001020
  77. GRB001019, Optical Observations
  78. GRB 001018, Possible Radio Afterglow
  79. GRB001018, Gamma Ray Observations
  80. IPN TRIANGULATION OF GRB001019
  81. IPN TRIANGULATION OF GRB001018
  82. IPN TRIANGULATION OF GRB 001017
  83. GRB 000926: Improved Absorber Redshift
  84. V,R,I band observations of GRB000926
  85. The Likely Optical/Infrared Afterglow of GRB 001011
  86. HETE positions added to GCN
  87. BeppoSAX ALERT: GRB001011
  88. GRB 001007, BVR-band observations
  89. GRB000926 - Amateur Optical Observations
  90. CONCAM null result on GRB001005
  91. IPN triangulation of GRB001007
  92. GRB 000926 : the host galaxy
  93. IPN triangulation of GRB001005
  94. GRB 000926 Chandra Observation
  95. IPN triangulation of GRB 001004
  96. Public availability of BeppoSAX data of GRB000926
  97. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  98. GRB 000926, Optical Decay
  99. GRB000926 - Optical observations
  100. GRB000926 - Optical observations

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