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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"

16214 results found.

  1. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  2. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  3. GRB010928(=H1770): Localization of a Long GRB by HETE
  4. GRB010921, negative optical observations
  5. GRB010921 field photometry
  6. GRB000926, Host Galaxy Observations
  7. GRB001109, Host Galaxy Spectroscopic Observations
  8. Probable SGR or Short Duration GRB Detected by HETE
  9. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  10. GRB 010222 - WHT BVRI images
  11. GRB 010629 Optical Observations
  12. SGR1900+14: High Fluence Burst Localized by HETE
  13. GRB010629, optical observations
  14. IPN triangulation of GRB010629
  15. GRB010629: A Burst Localized by HETE
  16. SGR1900+14: Second Burst Localized by HETE
  17. SGR1900+14: A Burst Localized by HETE
  18. SGR1806-20: A Second, Intense Burst Localized by HETE
  19. SGR1806-20: Localization by HETE
  20. HETE Fully-Automated GCN Notices
  21. GRB000301C: Late-time HST/STIS observation
  22. GRB010518: a faint BeppoSAX detection
  23. GRB000418: HST/STIS Second-epoch Observations
  24. X-ray precursors to the large flare from SGR 1900+14
  25. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  26. Millimeter observation of SGR 1900+14
  27. Chandra Observations of SGR 1900+14
  28. SGR1900+14, I-band observations
  29. GRB010412, field photometry
  30. Giant flare from SGR1900+14
  31. GRB 010326b Optical Observations
  32. GRB010412: BeppoSAX GRBM and WFC observations
  33. IPN Triangulation of GRB010412
  34. GRB010324, revised field photometry
  35. GRB 980326: Late-time HST/STIS observations
  36. GRB010324, field photometry
  37. GRB010326B, field photometry
  38. GRB010326, field photometry
  39. GRB010220, field photometry
  40. Further Optical Observations of GRB 010324
  41. GRB010222, CXO X-ray observations
  42. GRB010324, optical observations
  43. GRB010326B: Localization by HETE (2nd GRB for this date)
  44. GRB 010326 optical observations
  45. GRB010326: Refined Localization by HETE
  46. GRB010326: Localization by HETE
  47. Optical Observations of GRB 010324
  48. GRB010222, late-time optical observation
  49. Support extension to the BeppoSAX mission
  50. GRB 010222, Optical Observations
  51. GRB 010222: High-Resolution Keck Spectroscopy
  52. GRB 010222 HST/Chandra TOO
  53. GRB010222 further R-band photometry
  54. GRB 010222: Keck Spectroscopy
  55. GRB010214, field photometry
  56. GRB010222, field photometry
  57. GRB010222 further R-band photometry
  58. GRB 010222 Kyoto optical observation
  59. GRB010222 R-BAND OBSERVATION
  60. GRB010214 follow-up from Hanle
  61. GRB 010222: Near-IR Observations
  62. GRB 010222: Optical Observations
  63. GRB010222, radio observations
  64. GRB010222, optical observations
  65. GRB010222: BeppoSAX/NFI Observations
  66. GRB 010220, simultaneous optical observations
  67. GRB010220: BeppoSAX WFC and GRBM preliminary data
  68. GRB010214, optical observations
  69. GRB010214: BeppoSAX WFC and GRBM preliminary data
  70. GRB 010214: X-Ray afterglow
  71. GRB 010214 optical observation
  72. J-Band Observation of GRB 010214.
  73. GRB010213, Near-IR observations
  74. Possible InfraRed Transient of GRB 010214.
  75. GRB010213 detected by HETE
  76. IPN Status Report
  77. HETE Status
  78. Optical Observations of GRB 001018 at Keck
  79. Optical observations of GRB 001018 with JCAM
  80. GRB 001212 Optical Observation
  81. GRB 001212 Optical Observation
  82. GRB001120, optical observations
  83. Optical/NIR observations of GRB001109
  84. GRB 001109: deep JHK upper limits
  85. GRB 001109 X-ray afterglow with BeppoSAX
  86. CORRECTION to XMM-Newton observation of GRB001025
  87. GRB001109: Optical observations
  88. GRB001109, Radio observations
  89. GRB001105 BVRI field photometry correction
  90. GRB001105, BVRI field photometry
  91. GRB 001025B, Optical obervations
  92. GRB 991208: HST Imaging of the Host Galaxy
  93. GRB 001025B, I-band observations
  94. GRB001007: Optical observations
  95. GRB001007, Radio observations
  96. IPN TRIANGULATION OF GRB 001017
  97. V,R,I band observations of GRB000926
  98. GRB000926 - Amateur Optical Observations
  99. CONCAM null result on GRB001005
  100. HETE-2 Launches Successfully

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