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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"

28044 results found.

  1. SGR 1900+14, Chandra observations
  2. SGR1900+14, I-band observations
  3. GRB010412, field photometry
  4. Giant flare from SGR1900+14
  5. GRB 010326b Optical Observations
  6. GRB010412: BeppoSAX GRBM and WFC observations
  7. GRB010324, revised field photometry
  8. REVISED LOCATION OF GRB010326A
  9. GRB 980326: Late-time HST/STIS observations
  10. GRB010324, field photometry
  11. GRB010326B, field photometry
  12. GRB010326, field photometry
  13. GRB010220, field photometry
  14. Further Optical Observations of GRB 010324
  15. GRB010222, CXO X-ray observations
  16. GRB010324, optical observations
  17. GRB010326B: Localization by HETE (2nd GRB for this date)
  18. GRB 010326 optical observations
  19. GRB010326: Refined Localization by HETE
  20. GRB010326: Localization by HETE
  21. Optical Observations of GRB 010324
  22. GRB010222, late-time optical observation
  23. Support extension to the BeppoSAX mission
  24. GRB 010222 - HEGRA GeV/TeV Observations
  25. GRB010222: Chandra X-ray Observatory Observation
  26. GRB010222: Sub-millimeter vanishing act
  27. GRB010222 - Optical observation
  28. GRB 010222, Optical Observations
  29. GRB010222 - Optical observation
  30. GRB 010222: High-Resolution Keck Spectroscopy
  31. GRB 010214, I-band data
  32. GRB 010222
  33. GRB010222 further R-band photometry
  34. GRB010222: R-band data
  35. GRB 010222: Keck Spectroscopy
  36. GRB010214, field photometry
  37. GRB010222, field photometry
  38. GRB010222 further R-band photometry
  39. GRB010222, possible increase of optical decay slope
  40. GRB 010222 Kyoto optical observation
  41. GRB010222 R-BAND OBSERVATION
  42. GRB010214 follow-up from Hanle
  43. GRB 010222: Near-IR Observations
  44. GRB 010222: Optical Observations
  45. GRB010222: Optical decay slope
  46. GRB 010214, Optical Observations
  47. GRB010222, radio observations
  48. GRB010222, optical observations
  49. GRB010222: BeppoSAX/NFI Observations
  50. GRB010214B,Gamma Ray Observations
  51. GRB 010220, simultaneous optical observations
  52. GRB010220: BeppoSAX WFC and GRBM preliminary data
  53. GRB010214, candidate optical afterglow
  54. GRB010214, optical observations
  55. GRB010214: BeppoSAX WFC and GRBM preliminary data
  56. GRB 010214: X-Ray afterglow
  57. GRB 010214 optical observation
  58. GRB010213, Radio Observations
  59. J-Band Observation of GRB 010214.
  60. GRB010213, Near-IR observations
  61. Possible InfraRed Transient of GRB 010214.
  62. GRB 010214, optical observations
  63. GRB010213 detected by HETE
  64. IPN Status Report
  65. HETE Status
  66. IPN/RXTE TRIANGULATION OF GRB010126
  67. GRB010126 Optical Observations
  68. IPN TRIANGULATION OF GRB010126
  69. Optical Observations of GRB 001018 at Keck
  70. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  71. Optical observations of GRB 001018 with JCAM
  72. IPN TRIANGULATION OF GRB010115
  73. IPN TRIANGULATION OF GRB010109
  74. IPN TRIANGULATION OF GRB010109
  75. IPN triangulation of GRB010104
  76. IPN triangulation of GRB010103
  77. H band observation of GRB 001212
  78. IPN triangulation of GRB001219
  79. GRB 001212 Optical Observation
  80. GRB 001212 Optical Observation
  81. GRB 001212 possible OA in 2MASS
  82. IPN triangulation of GRB001212
  83. Confirmation of IPN position for GRB001204
  84. IPN triangulation of GRB001204 (short/hard)
  85. GRB001120, optical observations
  86. WSRT 4.8 GHz observations of GRB001109
  87. IPN triangulation of GRB001120
  88. GRB 001109: deep JHK upper limits
  89. GRB 001109 X-ray afterglow with BeppoSAX
  90. CORRECTION to XMM-Newton observation of GRB001025
  91. GRB001109, Radio observations
  92. GRB001105 BVRI field photometry correction
  93. GRB001105, BVRI field photometry
  94. IPN TRIANGULATION OF GRB001105
  95. GRB 001025B, Optical obervations
  96. GRB 991208: HST Imaging of the Host Galaxy
  97. GRB 001025B, I-band observations
  98. XMM-Newton observation of GRB001025
  99. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  100. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025

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