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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"

28042 results found.

  1. GRB010412, field photometry
  2. Giant flare from SGR1900+14
  3. GRB 010326b Optical Observations
  4. GRB010412: BeppoSAX GRBM and WFC observations
  5. GRB010324, revised field photometry
  6. REVISED LOCATION OF GRB010326A
  7. GRB 980326: Late-time HST/STIS observations
  8. GRB010324, field photometry
  9. GRB010326B, field photometry
  10. GRB010326, field photometry
  11. GRB010220, field photometry
  12. Further Optical Observations of GRB 010324
  13. GRB010222, CXO X-ray observations
  14. GRB010324, optical observations
  15. GRB010326B: Localization by HETE (2nd GRB for this date)
  16. GRB 010326 optical observations
  17. GRB010326: Refined Localization by HETE
  18. GRB010326: Localization by HETE
  19. Optical Observations of GRB 010324
  20. GRB010222, late-time optical observation
  21. Support extension to the BeppoSAX mission
  22. GRB 010222 - HEGRA GeV/TeV Observations
  23. GRB010222: Chandra X-ray Observatory Observation
  24. GRB010222: Sub-millimeter vanishing act
  25. GRB010222 - Optical observation
  26. GRB 010222, Optical Observations
  27. GRB010222 - Optical observation
  28. GRB 010222: High-Resolution Keck Spectroscopy
  29. GRB 010214, I-band data
  30. GRB 010222
  31. GRB010222 further R-band photometry
  32. GRB010222: R-band data
  33. GRB 010222: Keck Spectroscopy
  34. GRB010214, field photometry
  35. GRB010222, field photometry
  36. GRB010222 further R-band photometry
  37. GRB010222, possible increase of optical decay slope
  38. GRB 010222 Kyoto optical observation
  39. GRB010222 R-BAND OBSERVATION
  40. GRB010214 follow-up from Hanle
  41. GRB 010222: Near-IR Observations
  42. GRB 010222: Optical Observations
  43. GRB010222: Optical decay slope
  44. GRB 010214, Optical Observations
  45. GRB010222, radio observations
  46. GRB010222, optical observations
  47. GRB010222: BeppoSAX/NFI Observations
  48. GRB010214B,Gamma Ray Observations
  49. GRB 010220, simultaneous optical observations
  50. GRB010220: BeppoSAX WFC and GRBM preliminary data
  51. GRB010214, candidate optical afterglow
  52. GRB010214, optical observations
  53. GRB010214: BeppoSAX WFC and GRBM preliminary data
  54. GRB 010214: X-Ray afterglow
  55. GRB 010214 optical observation
  56. GRB010213, Radio Observations
  57. J-Band Observation of GRB 010214.
  58. GRB010213, Near-IR observations
  59. Possible InfraRed Transient of GRB 010214.
  60. GRB 010214, optical observations
  61. GRB010213 detected by HETE
  62. IPN Status Report
  63. HETE Status
  64. IPN/RXTE TRIANGULATION OF GRB010126
  65. GRB010126 Optical Observations
  66. IPN TRIANGULATION OF GRB010126
  67. Optical Observations of GRB 001018 at Keck
  68. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  69. Optical observations of GRB 001018 with JCAM
  70. IPN TRIANGULATION OF GRB010115
  71. IPN TRIANGULATION OF GRB010109
  72. IPN TRIANGULATION OF GRB010109
  73. IPN triangulation of GRB010104
  74. IPN triangulation of GRB010103
  75. H band observation of GRB 001212
  76. IPN triangulation of GRB001219
  77. GRB 001212 Optical Observation
  78. GRB 001212 Optical Observation
  79. GRB 001212 possible OA in 2MASS
  80. IPN triangulation of GRB001212
  81. Confirmation of IPN position for GRB001204
  82. IPN triangulation of GRB001204 (short/hard)
  83. GRB001120, optical observations
  84. WSRT 4.8 GHz observations of GRB001109
  85. IPN triangulation of GRB001120
  86. GRB 001109: deep JHK upper limits
  87. GRB 001109 X-ray afterglow with BeppoSAX
  88. CORRECTION to XMM-Newton observation of GRB001025
  89. GRB001109, Radio observations
  90. GRB001105 BVRI field photometry correction
  91. GRB001105, BVRI field photometry
  92. IPN TRIANGULATION OF GRB001105
  93. GRB 001025B, Optical obervations
  94. GRB 991208: HST Imaging of the Host Galaxy
  95. GRB 001025B, I-band observations
  96. XMM-Newton observation of GRB001025
  97. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  98. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  99. GRB001007: Optical observations
  100. ASM Localization of GRB 001025

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