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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"

24754 results found.

  1. GRB000418: HST/STIS Second-epoch Observations
  2. X-ray precursors to the large flare from SGR 1900+14
  3. GRB010427, Gamma Ray Observations
  4. SGR 1900+14: No evidence of extended X-ray emission
  5. SGR 1900+14 : RXTE observations
  6. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  7. SGR 1900+14: Correction to GCN 1049
  8. GRB 010222 /corrections to VBT data
  9. Millimeter observation of SGR 1900+14
  10. SGR 1900+14: Detection of extended X-ray emission
  11. SGR 1900+14, Chandra observations
  12. SGR1900+14, I-band observations
  13. GRB010412, field photometry
  14. Giant flare from SGR1900+14
  15. GRB 010326b Optical Observations
  16. GRB010412: BeppoSAX GRBM and WFC observations
  17. GRB010324, revised field photometry
  18. REVISED LOCATION OF GRB010326A
  19. GRB 980326: Late-time HST/STIS observations
  20. GRB010324, field photometry
  21. GRB010326B, field photometry
  22. GRB010326, field photometry
  23. GRB010220, field photometry
  24. Further Optical Observations of GRB 010324
  25. GRB010222, CXO X-ray observations
  26. GRB010324, optical observations
  27. GRB010326B: Localization by HETE (2nd GRB for this date)
  28. GRB 010326 optical observations
  29. GRB010326: Refined Localization by HETE
  30. GRB010326: Localization by HETE
  31. Optical Observations of GRB 010324
  32. GRB010222, late-time optical observation
  33. Support extension to the BeppoSAX mission
  34. GRB 010222 - HEGRA GeV/TeV Observations
  35. GRB010222: Chandra X-ray Observatory Observation
  36. GRB010222: Sub-millimeter vanishing act
  37. GRB010222 - Optical observation
  38. GRB 010222, Optical Observations
  39. GRB010222 - Optical observation
  40. GRB 010222: High-Resolution Keck Spectroscopy
  41. GRB 010214, I-band data
  42. GRB 010222
  43. GRB010222 further R-band photometry
  44. GRB010222: R-band data
  45. GRB 010222: Keck Spectroscopy
  46. GRB010214, field photometry
  47. GRB010222, field photometry
  48. GRB010222 further R-band photometry
  49. GRB010222, possible increase of optical decay slope
  50. GRB 010222 Kyoto optical observation
  51. GRB010222 R-BAND OBSERVATION
  52. GRB010214 follow-up from Hanle
  53. GRB 010222: Near-IR Observations
  54. GRB 010222: Optical Observations
  55. GRB010222: Optical decay slope
  56. GRB 010214, Optical Observations
  57. GRB010222, radio observations
  58. GRB010222, optical observations
  59. GRB010222: BeppoSAX/NFI Observations
  60. GRB010214B,Gamma Ray Observations
  61. GRB 010220, simultaneous optical observations
  62. GRB010220: BeppoSAX WFC and GRBM preliminary data
  63. GRB010214, candidate optical afterglow
  64. GRB010214, optical observations
  65. GRB010214: BeppoSAX WFC and GRBM preliminary data
  66. GRB 010214: X-Ray afterglow
  67. GRB 010214 optical observation
  68. GRB010213, Radio Observations
  69. J-Band Observation of GRB 010214.
  70. GRB010213, Near-IR observations
  71. Possible InfraRed Transient of GRB 010214.
  72. GRB 010214, optical observations
  73. GRB010213 detected by HETE
  74. IPN Status Report
  75. HETE Status
  76. IPN/RXTE TRIANGULATION OF GRB010126
  77. GRB010126 Optical Observations
  78. IPN TRIANGULATION OF GRB010126
  79. Optical Observations of GRB 001018 at Keck
  80. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  81. Optical observations of GRB 001018 with JCAM
  82. IPN TRIANGULATION OF GRB010115
  83. IPN TRIANGULATION OF GRB010109
  84. IPN TRIANGULATION OF GRB010109
  85. IPN triangulation of GRB010104
  86. IPN triangulation of GRB010103
  87. H band observation of GRB 001212
  88. IPN triangulation of GRB001219
  89. GRB 001212 Optical Observation
  90. GRB 001212 Optical Observation
  91. GRB 001212 possible OA in 2MASS
  92. IPN triangulation of GRB001212
  93. Confirmation of IPN position for GRB001204
  94. IPN triangulation of GRB001204 (short/hard)
  95. GRB001120, optical observations
  96. WSRT 4.8 GHz observations of GRB001109
  97. IPN triangulation of GRB001120
  98. GRB 001109: deep JHK upper limits
  99. GRB 001109 X-ray afterglow with BeppoSAX
  100. CORRECTION to XMM-Newton observation of GRB001025

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