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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"

28053 results found.

  1. X-ray precursors to the large flare from SGR 1900+14
  2. GRB010427, Gamma Ray Observations
  3. SGR 1900+14: No evidence of extended X-ray emission
  4. SGR 1900+14 : RXTE observations
  5. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  6. SGR 1900+14: Correction to GCN 1049
  7. GRB 010222 /corrections to VBT data
  8. Millimeter observation of SGR 1900+14
  9. SGR 1900+14: Detection of extended X-ray emission
  10. SGR 1900+14, Chandra observations
  11. SGR1900+14, I-band observations
  12. GRB010412, field photometry
  13. Giant flare from SGR1900+14
  14. GRB 010326b Optical Observations
  15. GRB010412: BeppoSAX GRBM and WFC observations
  16. GRB010324, revised field photometry
  17. REVISED LOCATION OF GRB010326A
  18. GRB 980326: Late-time HST/STIS observations
  19. GRB010324, field photometry
  20. GRB010326B, field photometry
  21. GRB010326, field photometry
  22. GRB010220, field photometry
  23. Further Optical Observations of GRB 010324
  24. GRB010222, CXO X-ray observations
  25. GRB010324, optical observations
  26. GRB010326B: Localization by HETE (2nd GRB for this date)
  27. GRB 010326 optical observations
  28. GRB010326: Refined Localization by HETE
  29. GRB010326: Localization by HETE
  30. Optical Observations of GRB 010324
  31. GRB010222, late-time optical observation
  32. Support extension to the BeppoSAX mission
  33. GRB 010222 - HEGRA GeV/TeV Observations
  34. GRB010222: Chandra X-ray Observatory Observation
  35. GRB010222: Sub-millimeter vanishing act
  36. GRB010222 - Optical observation
  37. GRB 010222, Optical Observations
  38. GRB010222 - Optical observation
  39. GRB 010222: High-Resolution Keck Spectroscopy
  40. GRB 010214, I-band data
  41. GRB 010222
  42. GRB010222 further R-band photometry
  43. GRB010222: R-band data
  44. GRB 010222: Keck Spectroscopy
  45. GRB010214, field photometry
  46. GRB010222, field photometry
  47. GRB010222 further R-band photometry
  48. GRB010222, possible increase of optical decay slope
  49. GRB 010222 Kyoto optical observation
  50. GRB010222 R-BAND OBSERVATION
  51. GRB010214 follow-up from Hanle
  52. GRB 010222: Near-IR Observations
  53. GRB 010222: Optical Observations
  54. GRB010222: Optical decay slope
  55. GRB 010214, Optical Observations
  56. GRB010222, radio observations
  57. GRB010222, optical observations
  58. GRB010222: BeppoSAX/NFI Observations
  59. GRB010214B,Gamma Ray Observations
  60. GRB 010220, simultaneous optical observations
  61. GRB010220: BeppoSAX WFC and GRBM preliminary data
  62. GRB010214, candidate optical afterglow
  63. GRB010214, optical observations
  64. GRB010214: BeppoSAX WFC and GRBM preliminary data
  65. GRB 010214: X-Ray afterglow
  66. GRB 010214 optical observation
  67. GRB010213, Radio Observations
  68. J-Band Observation of GRB 010214.
  69. GRB010213, Near-IR observations
  70. Possible InfraRed Transient of GRB 010214.
  71. GRB 010214, optical observations
  72. GRB010213 detected by HETE
  73. IPN Status Report
  74. HETE Status
  75. IPN/RXTE TRIANGULATION OF GRB010126
  76. GRB010126 Optical Observations
  77. IPN TRIANGULATION OF GRB010126
  78. Optical Observations of GRB 001018 at Keck
  79. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  80. Optical observations of GRB 001018 with JCAM
  81. IPN TRIANGULATION OF GRB010115
  82. IPN TRIANGULATION OF GRB010109
  83. IPN TRIANGULATION OF GRB010109
  84. IPN triangulation of GRB010104
  85. IPN triangulation of GRB010103
  86. H band observation of GRB 001212
  87. IPN triangulation of GRB001219
  88. GRB 001212 Optical Observation
  89. GRB 001212 Optical Observation
  90. GRB 001212 possible OA in 2MASS
  91. IPN triangulation of GRB001212
  92. Confirmation of IPN position for GRB001204
  93. IPN triangulation of GRB001204 (short/hard)
  94. GRB001120, optical observations
  95. WSRT 4.8 GHz observations of GRB001109
  96. IPN triangulation of GRB001120
  97. GRB 001109: deep JHK upper limits
  98. GRB 001109 X-ray afterglow with BeppoSAX
  99. CORRECTION to XMM-Newton observation of GRB001025
  100. GRB001109, Radio observations

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