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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"

24659 results found.

  1. GRB991216 Optical and infrared observations of Beethoven Burst
  2. GRB 991216 Radio Observations
  3. GRB 991208 Keck Spectroscopy
  4. GRB 991208 Infrared Detection
  5. GRB991216
  6. GRB 991216--Summary of RXTE Observations
  7. GRB 991216 Optical Observations
  8. GRB 991216, optical observations
  9. GRB 991208 SAO-RAS Spectroscopy
  10. SAX J2303.2+0015: an x-ray/GRB?
  11. GRB 991216, Optical Transient
  12. GRB991216 ('Beethoven Burst') B, R, and K Observations
  13. GRB991216, infrared observations
  14. GRB 991208 optical observations
  15. GRB 991216 Optical Observation
  16. GRB 991216: Extremely bright BATSE burst
  17. R-band Observations of GRB991208 at TNG
  18. GRB991208, optical observations
  19. GRB 991208, Optical Observation
  20. GRB991208, optical observations
  21. GRB 991208 optical observations
  22. Optical Observations of GRB991105
  23. GRB991106: BeppoSAX/BATSE results
  24. GRB991106, near-infrared observations
  25. BeppoSAX NFI Observation of GRB991106
  26. GRB 991106, radio observations
  27. GRB991106: the first BeppoSAX short GRB detection?
  28. GRB 991105: BATSE Observations
  29. GRB 991106 Optical Observations
  30. GRB991106, optical observation at SAO-RAS
  31. GRB 991106, LOTIS Optical Observations
  32. GRB991105: SAX-GRBM/-WFC detection
  33. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  34. GRB 991014, Optical Observations
  35. GRB 991014 - BeppoSAX NFI observations
  36. GRB 991014, radio observations
  37. GRB 991014, Optical Observations
  38. GRB 991014, optical observations
  39. GRB 990915 optical observations
  40. Optical Observations of GRB990907
  41. GRB990907: BeppoSAX follow up and X-ray afterglow
  42. GRB990907 and 990908
  43. GRB 990712 Late Optical Decay and Host Galaxy
  44. GRB990806 BeppoSAX follow up
  45. GRB990806: BATSE Observations
  46. GRB 990806 Optical observations
  47. GRB 990806, Optical Observations
  48. GRB 990806, optical observations
  49. GRB 990806, Optical Observations
  50. GRB990806 UBVRIJHK observations
  51. GRB 990712 Optical Observations
  52. GRB 990712
  53. Late-time HST/STIS Observations of GRB 990510
  54. BeppoSAX NFI Observation of GRB990705
  55. BeppoSAX NFI Observation of GRB990705
  56. GRB 990705, R-band observations
  57. Infrared and Optical Observations of GRB990705
  58. GRB990704: SAX-NFI results summary
  59. GRB990704 radio and optical observations
  60. GRB990704
  61. GRB990704, optical observations
  62. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  63. Optical Observations of GRB990627
  64. BeppoSAX: GRB990625
  65. Late-time HST/STIS Observation of GRB 990123
  66. Optical Observations of GRB 990506
  67. GRB990527 Optical Observations
  68. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  69. Late Afterglows of GRBs 990510, 990123
  70. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  71. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  72. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  73. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  74. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  75. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  76. radio observations of X-ray/GRB transient field
  77. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  78. Optical report on X-ray/GRB transient
  79. radio detection of X-ray/GRB transient
  80. BeppoSAX: A new fast X-ray transient
  81. GRB 990510: optical observations
  82. GRB 990510: optical linear polarization
  83. GRB 990510: optical observations
  84. GRB990510: X-ray afterglow
  85. GRB 990510: Broad Band Break
  86. GRB 990510: BATSE Observations
  87. GRB 990510: BeppoSAX/GRBM observations
  88. GRB990510 optical observations
  89. GRB 990510 optical observations
  90. GRB 990506 Radio Observations
  91. GRB 990123, optical monitoring
  92. GRB 990506: BATSE Observations
  93. GRB 990506, optical observations
  94. GRB 990506, Optical Observations
  95. GRB 990506 optical observations
  96. GRB 990506, optical observations
  97. GRB 990506, armchair astronomy
  98. GRB 990506, optical observations from +1 to +3 hours
  99. GRB 990506, optical observations
  100. GRB990506 observation plan

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