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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"

36155 results found.

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

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