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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"

45431 results found.

  1. GRB991105: SAX-GRBM/-WFC detection
  2. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  3. GRB ALERT: GRB991105
  4. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  5. GRB 991014, Optical Observations
  6. GRB 991014 - BeppoSAX NFI observations
  7. GRB 991014, Optical Observations
  8. GRB 991014, radio observations
  9. GRB991014 BATSE Observations
  10. GRB 991014, Optical Observations
  11. GRB 991014, optical observations
  12. Super-LOTIS optical observation of GRB991014
  13. IPN/NFI error box for GRB991014
  14. IPN localization of GRB991014 - CORRECTION
  15. IPN localization of GRB991014
  16. BeppoSAX ALERT: GRB991014
  17. GRB 990915 optical observations
  18. GRB 990907 optical observations
  19. Optical Observations of GRB990907
  20. IPN error box for GRB990915 (=BATSE 7766)
  21. IPN localization of BATSE #7766 (GRB990915)
  22. GRB990907: BeppoSAX follow up and X-ray afterglow
  23. GRB990907 and 990908
  24. IPN localization of GRB990907
  25. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  26. GRB990907: refined WFC position
  27. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  28. GRB 990712 Late Optical Decay and Host Galaxy
  29. GRB 990712, Optical Observation
  30. GRB990806 BeppoSAX follow up
  31. GRB990806: BATSE Observations
  32. GRB 990806 Optical observations
  33. Optical Observations of GRB990806
  34. GRB 990806, Optical Observations
  35. GRB 990806, optical observations
  36. GRB 990806, Optical Observations
  37. GRB990806 UBVRIJHK observations
  38. GRB990806: possible X-ray afterglow, BeppoSAX
  39. BeppoSAX ALERT GRB990806: Summer GRB
  40. GRB 990712 Optical Observations
  41. GRB990705: No Evidence for Neutrino Signal
  42. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  43. VLT spectrum of GRB990712
  44. GRB 990712
  45. Late-time HST/STIS Observations of GRB 990510
  46. Refined BeppoSAX-WFC position of GRB990712
  47. BeppoSAX NFI Observation of GRB990705
  48. BeppoSAX NFI Observation of GRB990705
  49. Updated Astrometry for the IR Counterpart of GRB990705
  50. GRB 990705, R-band observations
  51. Updated IPN localization of GRB990705
  52. IPN localization of GRB990704
  53. IPN localization of GRB990705
  54. Infrared and Optical Observations of GRB990705
  55. GRB 990705, radio observations
  56. GRB990704: SAX-NFI results summary
  57. GRB990704 radio and optical observations
  58. BeppoSAX GRB990705: possible X-ray afterglow
  59. GRB 990704 X-ray Observations
  60. GRB 990704 Optical Observations
  61. GRB 990704, optical observations
  62. GRB990704
  63. GRB990705: Intriguing Positional Coincidences
  64. GRB990704
  65. Refined BeppoSAX-WFC position of GRB990704: Errata Corrige
  66. GRB990704, optical observations
  67. GRB990704: possible X-ray afterglow
  68. Identification of a possible optical counterpart for GRB990704
  69. GRB990704
  70. Refined BeppoSAX-WFC position of GRB990704
  71. GRB990704: BeppoSAX detection
  72. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  73. Optical Observations of GRB990627
  74. GRB 990627, radio observations
  75. GRB990627: BeppoSAX-WFC final location
  76. BeppoSAX: GRB990625
  77. Late-time HST/STIS Observation of GRB 990123
  78. GRB 990506 - clarification to GCN 352
  79. GRB 990506 - Optical Observations
  80. Optical Observations of GRB 990506
  81. GRB 990506 Radio Transient
  82. GRB990527 Optical Observations
  83. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  84. IPN error box for GRB990527
  85. Late Afterglows of GRBs 990510, 990123
  86. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  87. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  88. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  89. GRB 990506 optical observation
  90. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  91. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  92. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  93. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  94. radio observations of X-ray/GRB transient field
  95. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  96. Optical report on X-ray/GRB transient
  97. radio detection of X-ray/GRB transient
  98. BeppoSAX: A new fast X-ray transient
  99. GRB 990510: optical observations
  100. GRB990510: photometric and spectroscopic observations with the VLT

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