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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"

25037 results found.

  1. REVISED LOCATION OF GRB010326A
  2. GRB 980326: Late-time HST/STIS observations
  3. GRB010324, field photometry
  4. GRB010326B, field photometry
  5. GRB010326, field photometry
  6. GRB010220, field photometry
  7. Further Optical Observations of GRB 010324
  8. GRB010222, CXO X-ray observations
  9. GRB010324, optical observations
  10. GRB010326B: Localization by HETE (2nd GRB for this date)
  11. GRB 010326 optical observations
  12. GRB010326: Refined Localization by HETE
  13. GRB010326: Localization by HETE
  14. Optical Observations of GRB 010324
  15. GRB010222, late-time optical observation
  16. Support extension to the BeppoSAX mission
  17. GRB 010222 - HEGRA GeV/TeV Observations
  18. GRB010222: Chandra X-ray Observatory Observation
  19. GRB010222: Sub-millimeter vanishing act
  20. GRB010222 - Optical observation
  21. GRB 010222, Optical Observations
  22. GRB010222 - Optical observation
  23. GRB 010222: High-Resolution Keck Spectroscopy
  24. GRB 010214, I-band data
  25. GRB 010222
  26. GRB010222 further R-band photometry
  27. GRB010222: R-band data
  28. GRB 010222: Keck Spectroscopy
  29. GRB010214, field photometry
  30. GRB010222, field photometry
  31. GRB010222 further R-band photometry
  32. GRB010222, possible increase of optical decay slope
  33. GRB 010222 Kyoto optical observation
  34. GRB010222 R-BAND OBSERVATION
  35. GRB010214 follow-up from Hanle
  36. GRB 010222: Near-IR Observations
  37. GRB 010222: Optical Observations
  38. GRB010222: Optical decay slope
  39. GRB 010214, Optical Observations
  40. GRB010222, radio observations
  41. GRB010222, optical observations
  42. GRB010222: BeppoSAX/NFI Observations
  43. GRB010214B,Gamma Ray Observations
  44. GRB 010220, simultaneous optical observations
  45. GRB010220: BeppoSAX WFC and GRBM preliminary data
  46. GRB010214, candidate optical afterglow
  47. GRB010214, optical observations
  48. GRB010214: BeppoSAX WFC and GRBM preliminary data
  49. GRB 010214: X-Ray afterglow
  50. GRB 010214 optical observation
  51. GRB010213, Radio Observations
  52. J-Band Observation of GRB 010214.
  53. GRB010213, Near-IR observations
  54. Possible InfraRed Transient of GRB 010214.
  55. GRB 010214, optical observations
  56. GRB010213 detected by HETE
  57. IPN Status Report
  58. HETE Status
  59. IPN/RXTE TRIANGULATION OF GRB010126
  60. GRB010126 Optical Observations
  61. IPN TRIANGULATION OF GRB010126
  62. Optical Observations of GRB 001018 at Keck
  63. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  64. Optical observations of GRB 001018 with JCAM
  65. IPN TRIANGULATION OF GRB010115
  66. IPN TRIANGULATION OF GRB010109
  67. IPN TRIANGULATION OF GRB010109
  68. IPN triangulation of GRB010104
  69. IPN triangulation of GRB010103
  70. H band observation of GRB 001212
  71. IPN triangulation of GRB001219
  72. GRB 001212 Optical Observation
  73. GRB 001212 Optical Observation
  74. GRB 001212 possible OA in 2MASS
  75. IPN triangulation of GRB001212
  76. Confirmation of IPN position for GRB001204
  77. IPN triangulation of GRB001204 (short/hard)
  78. GRB001120, optical observations
  79. WSRT 4.8 GHz observations of GRB001109
  80. IPN triangulation of GRB001120
  81. GRB 001109: deep JHK upper limits
  82. GRB 001109 X-ray afterglow with BeppoSAX
  83. CORRECTION to XMM-Newton observation of GRB001025
  84. GRB001109, Radio observations
  85. GRB001105 BVRI field photometry correction
  86. GRB001105, BVRI field photometry
  87. IPN TRIANGULATION OF GRB001105
  88. GRB 001025B, Optical obervations
  89. GRB 991208: HST Imaging of the Host Galaxy
  90. GRB 001025B, I-band observations
  91. XMM-Newton observation of GRB001025
  92. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  93. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  94. GRB001007: Optical observations
  95. ASM Localization of GRB 001025
  96. GRB001007, Radio observations
  97. GRB 001018, Possible Radio Afterglow
  98. GRB001018, Gamma Ray Observations
  99. IPN TRIANGULATION OF GRB001019
  100. IPN TRIANGULATION OF GRB001018

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