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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"

26499 results found.

  1. GRB 010326 optical observations
  2. GRB010326: Refined Localization by HETE
  3. GRB010326: Localization by HETE
  4. Duration, ECT, peak flux and fluence of GRB010324
  5. Optical Observations of GRB 010324
  6. GRB990705, VLT-FORS1 observations of the host galaxy
  7. GRB010222, late-time optical observation
  8. Support extension to the BeppoSAX mission
  9. GRB 010222 - HEGRA GeV/TeV Observations
  10. GRB010222: Sub-millimeter vanishing act
  11. GRB010222 - Optical observation
  12. GRB 010222, Optical Observations
  13. GRB 010222: High-Resolution Keck Spectroscopy
  14. GRB 010214, I-band data
  15. GRB 010222
  16. GRB010222 further R-band photometry
  17. GRB 010222: Keck Spectroscopy
  18. GRB010214, field photometry
  19. GRB010222, field photometry
  20. GRB010222 further R-band photometry
  21. GRB010222, possible increase of optical decay slope
  22. GRB 010222 Kyoto optical observation
  23. GRB010222 R-BAND OBSERVATION
  24. GRB010214 follow-up from Hanle
  25. GRB 010222: Near-IR Observations
  26. GRB 010222: Optical Observations
  27. GRB 010222, Decay Slope Confirmed
  28. GRB 010214, Optical Observations
  29. GRB010222, radio observations
  30. GRB010222, optical observations
  31. GRB010214B,Gamma Ray Observations
  32. GRB 010220, simultaneous optical observations
  33. GRB010220: BeppoSAX WFC and GRBM preliminary data
  34. GRB010214, candidate optical afterglow
  35. GRB010214, optical observations
  36. GRB010214: BeppoSAX WFC and GRBM preliminary data
  37. GRB 010214: X-Ray afterglow
  38. GRB 010214 optical observation
  39. GRB010213 Optical Observation
  40. J-Band Observation of GRB 010214.
  41. GRB010213, Near-IR observations
  42. Possible InfraRed Transient of GRB 010214.
  43. GRB010214 Optical Observation
  44. GRB010213 detected by HETE
  45. IPN Status Report
  46. HETE Status
  47. IPN/RXTE TRIANGULATION OF GRB010126
  48. GRB010126: CONCAM crude optical limits during GRB
  49. GRB010126 Optical Observations
  50. GRB010126 optical observations
  51. GRB010126: Optical observations
  52. IPN TRIANGULATION OF GRB010126
  53. IPN/RXTE TRIANGULATION OF GRB010126
  54. GRB 010119, optical observations
  55. GRB010119: Optical observations
  56. Optical Observations of GRB 001018 at Keck
  57. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  58. Optical observations of GRB 001018 with JCAM
  59. IPN TRIANGULATION OF GRB010115
  60. IPN TRIANGULATION OF GRB010109
  61. IPN TRIANGULATION OF GRB010109
  62. IPN triangulation of GRB010104
  63. IPN triangulation of GRB010103
  64. IPN triangulation of GRB001219
  65. GRB 001212 Optical Observation
  66. GRB 001212 Optical Observation
  67. GRB 001212 possible OA in 2MASS
  68. GRB 001212 possible OA
  69. IPN triangulation of GRB001212
  70. GRB001204: Optical observations
  71. Confirmation of IPN position for GRB001204
  72. IPN triangulation of GRB001204 (short/hard)
  73. GRB 001105, further optical observations
  74. GRB001120, optical observations
  75. IPN triangulation of GRB001120
  76. Optical/NIR observations of GRB001109
  77. GRB 001109: deep JHK upper limits
  78. GRB 001109 X-ray afterglow with BeppoSAX
  79. CORRECTION to XMM-Newton observation of GRB001025
  80. GRB001109: Optical observations
  81. GRB001109, Radio observations
  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. XMM-Newton observation of GRB001025
  91. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  92. IPN triangulation of GRB001025
  93. GRB001007: Optical observations
  94. GRB001007, Radio observations
  95. IPN TRIANGULATION OF GRB001020
  96. GRB001018, Gamma Ray Observations
  97. IPN TRIANGULATION OF GRB001019
  98. CORRECTION TO PEAK FLUX OF GRB001018
  99. IPN TRIANGULATION OF GRB001018
  100. IPN TRIANGULATION OF GRB 001017

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