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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"

36154 results found.

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

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