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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"

28049 results found.

  1. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  2. SGR 1900+14: Correction to GCN 1049
  3. GRB 010222 /corrections to VBT data
  4. Millimeter observation of SGR 1900+14
  5. SGR 1900+14: Detection of extended X-ray emission
  6. SGR 1900+14, Chandra observations
  7. SGR1900+14, I-band observations
  8. GRB010412, field photometry
  9. Giant flare from SGR1900+14
  10. GRB 010326b Optical Observations
  11. GRB010412: BeppoSAX GRBM and WFC observations
  12. GRB010324, revised field photometry
  13. REVISED LOCATION OF GRB010326A
  14. GRB 980326: Late-time HST/STIS observations
  15. GRB010324, field photometry
  16. GRB010326B, field photometry
  17. GRB010326, field photometry
  18. GRB010220, field photometry
  19. Further Optical Observations of GRB 010324
  20. GRB010222, CXO X-ray observations
  21. GRB010324, optical observations
  22. GRB010326B: Localization by HETE (2nd GRB for this date)
  23. GRB 010326 optical observations
  24. GRB010326: Refined Localization by HETE
  25. GRB010326: Localization by HETE
  26. Optical Observations of GRB 010324
  27. GRB010222, late-time optical observation
  28. Support extension to the BeppoSAX mission
  29. GRB 010222 - HEGRA GeV/TeV Observations
  30. GRB010222: Chandra X-ray Observatory Observation
  31. GRB010222: Sub-millimeter vanishing act
  32. GRB010222 - Optical observation
  33. GRB 010222, Optical Observations
  34. GRB010222 - Optical observation
  35. GRB 010222: High-Resolution Keck Spectroscopy
  36. GRB 010214, I-band data
  37. GRB 010222
  38. GRB010222 further R-band photometry
  39. GRB010222: R-band data
  40. GRB 010222: Keck Spectroscopy
  41. GRB010214, field photometry
  42. GRB010222, field photometry
  43. GRB010222 further R-band photometry
  44. GRB010222, possible increase of optical decay slope
  45. GRB 010222 Kyoto optical observation
  46. GRB010222 R-BAND OBSERVATION
  47. GRB010214 follow-up from Hanle
  48. GRB 010222: Near-IR Observations
  49. GRB 010222: Optical Observations
  50. GRB010222: Optical decay slope
  51. GRB 010214, Optical Observations
  52. GRB010222, radio observations
  53. GRB010222, optical observations
  54. GRB010222: BeppoSAX/NFI Observations
  55. GRB010214B,Gamma Ray Observations
  56. GRB 010220, simultaneous optical observations
  57. GRB010220: BeppoSAX WFC and GRBM preliminary data
  58. GRB010214, candidate optical afterglow
  59. GRB010214, optical observations
  60. GRB010214: BeppoSAX WFC and GRBM preliminary data
  61. GRB 010214: X-Ray afterglow
  62. GRB 010214 optical observation
  63. GRB010213, Radio Observations
  64. J-Band Observation of GRB 010214.
  65. GRB010213, Near-IR observations
  66. Possible InfraRed Transient of GRB 010214.
  67. GRB 010214, optical observations
  68. GRB010213 detected by HETE
  69. IPN Status Report
  70. HETE Status
  71. IPN/RXTE TRIANGULATION OF GRB010126
  72. GRB010126 Optical Observations
  73. IPN TRIANGULATION OF GRB010126
  74. Optical Observations of GRB 001018 at Keck
  75. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  76. Optical observations of GRB 001018 with JCAM
  77. IPN TRIANGULATION OF GRB010115
  78. IPN TRIANGULATION OF GRB010109
  79. IPN TRIANGULATION OF GRB010109
  80. IPN triangulation of GRB010104
  81. IPN triangulation of GRB010103
  82. H band observation of GRB 001212
  83. IPN triangulation of GRB001219
  84. GRB 001212 Optical Observation
  85. GRB 001212 Optical Observation
  86. GRB 001212 possible OA in 2MASS
  87. IPN triangulation of GRB001212
  88. Confirmation of IPN position for GRB001204
  89. IPN triangulation of GRB001204 (short/hard)
  90. GRB001120, optical observations
  91. WSRT 4.8 GHz observations of GRB001109
  92. IPN triangulation of GRB001120
  93. GRB 001109: deep JHK upper limits
  94. GRB 001109 X-ray afterglow with BeppoSAX
  95. CORRECTION to XMM-Newton observation of GRB001025
  96. GRB001109, Radio observations
  97. GRB001105 BVRI field photometry correction
  98. GRB001105, BVRI field photometry
  99. IPN TRIANGULATION OF GRB001105
  100. GRB 001025B, Optical obervations

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