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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"

28047 results found.

  1. GRB 010222 /corrections to VBT data
  2. Millimeter observation of SGR 1900+14
  3. SGR 1900+14: Detection of extended X-ray emission
  4. SGR 1900+14, Chandra observations
  5. SGR1900+14, I-band observations
  6. GRB010412, field photometry
  7. Giant flare from SGR1900+14
  8. GRB 010326b Optical Observations
  9. GRB010412: BeppoSAX GRBM and WFC observations
  10. GRB010324, revised field photometry
  11. REVISED LOCATION OF GRB010326A
  12. GRB 980326: Late-time HST/STIS observations
  13. GRB010324, field photometry
  14. GRB010326B, field photometry
  15. GRB010326, field photometry
  16. GRB010220, field photometry
  17. Further Optical Observations of GRB 010324
  18. GRB010222, CXO X-ray observations
  19. GRB010324, optical observations
  20. GRB010326B: Localization by HETE (2nd GRB for this date)
  21. GRB 010326 optical observations
  22. GRB010326: Refined Localization by HETE
  23. GRB010326: Localization by HETE
  24. Optical Observations of GRB 010324
  25. GRB010222, late-time optical observation
  26. Support extension to the BeppoSAX mission
  27. GRB 010222 - HEGRA GeV/TeV Observations
  28. GRB010222: Chandra X-ray Observatory Observation
  29. GRB010222: Sub-millimeter vanishing act
  30. GRB010222 - Optical observation
  31. GRB 010222, Optical Observations
  32. GRB010222 - Optical observation
  33. GRB 010222: High-Resolution Keck Spectroscopy
  34. GRB 010214, I-band data
  35. GRB 010222
  36. GRB010222 further R-band photometry
  37. GRB010222: R-band data
  38. GRB 010222: Keck Spectroscopy
  39. GRB010214, field photometry
  40. GRB010222, field photometry
  41. GRB010222 further R-band photometry
  42. GRB010222, possible increase of optical decay slope
  43. GRB 010222 Kyoto optical observation
  44. GRB010222 R-BAND OBSERVATION
  45. GRB010214 follow-up from Hanle
  46. GRB 010222: Near-IR Observations
  47. GRB 010222: Optical Observations
  48. GRB010222: Optical decay slope
  49. GRB 010214, Optical Observations
  50. GRB010222, radio observations
  51. GRB010222, optical observations
  52. GRB010222: BeppoSAX/NFI Observations
  53. GRB010214B,Gamma Ray Observations
  54. GRB 010220, simultaneous optical observations
  55. GRB010220: BeppoSAX WFC and GRBM preliminary data
  56. GRB010214, candidate optical afterglow
  57. GRB010214, optical observations
  58. GRB010214: BeppoSAX WFC and GRBM preliminary data
  59. GRB 010214: X-Ray afterglow
  60. GRB 010214 optical observation
  61. GRB010213, Radio Observations
  62. J-Band Observation of GRB 010214.
  63. GRB010213, Near-IR observations
  64. Possible InfraRed Transient of GRB 010214.
  65. GRB 010214, optical observations
  66. GRB010213 detected by HETE
  67. IPN Status Report
  68. HETE Status
  69. IPN/RXTE TRIANGULATION OF GRB010126
  70. GRB010126 Optical Observations
  71. IPN TRIANGULATION OF GRB010126
  72. Optical Observations of GRB 001018 at Keck
  73. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  74. Optical observations of GRB 001018 with JCAM
  75. IPN TRIANGULATION OF GRB010115
  76. IPN TRIANGULATION OF GRB010109
  77. IPN TRIANGULATION OF GRB010109
  78. IPN triangulation of GRB010104
  79. IPN triangulation of GRB010103
  80. H band observation of GRB 001212
  81. IPN triangulation of GRB001219
  82. GRB 001212 Optical Observation
  83. GRB 001212 Optical Observation
  84. GRB 001212 possible OA in 2MASS
  85. IPN triangulation of GRB001212
  86. Confirmation of IPN position for GRB001204
  87. IPN triangulation of GRB001204 (short/hard)
  88. GRB001120, optical observations
  89. WSRT 4.8 GHz observations of GRB001109
  90. IPN triangulation of GRB001120
  91. GRB 001109: deep JHK upper limits
  92. GRB 001109 X-ray afterglow with BeppoSAX
  93. CORRECTION to XMM-Newton observation of GRB001025
  94. GRB001109, Radio observations
  95. GRB001105 BVRI field photometry correction
  96. GRB001105, BVRI field photometry
  97. IPN TRIANGULATION OF GRB001105
  98. GRB 001025B, Optical obervations
  99. GRB 991208: HST Imaging of the Host Galaxy
  100. GRB 001025B, I-band observations

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