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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').

31197 results found.

  1. GRB 991216--Summary of RXTE Observations
  2. GRB 991216 Optical Observations
  3. GRB 991216, optical observations
  4. GRB 991208 SAO-RAS Spectroscopy
  5. SAX J2303.2+0015: an x-ray/GRB?
  6. GRB 991216, Optical Transient
  7. GRB 991216, Optical Afterglow
  8. GRB 991216: Comparison with DPOSS images
  9. GRB 991208 optical observations
  10. Lowell/Perkins observation of GRB 991216
  11. GRB 991216 Optical Observation
  12. GRB 991208 Keck Spectroscopy
  13. GRB 991216: Extremely bright BATSE burst
  14. GRB991208, optical observations
  15. GRB 991208 Keck Spectroscopy
  16. GRB991208 - millimeter detection
  17. GRB 991208, Optical Observation
  18. GRB 991208 - OVRO detection
  19. GRB 991208 Optical Decay
  20. GRB 991208 optical observations
  21. GRB 991208 optical observations
  22. GRB 991208: Radio Observations
  23. IPN localization of GRB991208
  24. Optical Observations of GRB991105
  25. GRB991106: BeppoSAX/BATSE results
  26. GRB 991106, optical observations
  27. GRB991106, near-infrared observations
  28. BeppoSAX NFI Observation of GRB991106
  29. GRB 991106, radio observations
  30. GRB991106: the first BeppoSAX short GRB detection?
  31. GRB 991105: BATSE Observations
  32. IPN localization of GRB991105
  33. GRB 991106 Optical Observations
  34. GRB 991105, optical observations
  35. GRB991106, optical observation at SAO-RAS
  36. GRB 991106, LOTIS Optical Observations
  37. GRB 991106, optical observations
  38. BeppoSAX GRB Alert: GRB991106
  39. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  40. GRB ALERT: GRB991105
  41. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  42. GRB 991014, Optical Observations
  43. GRB 991014 - BeppoSAX NFI observations
  44. GRB 991014, Optical Observations
  45. GRB 991014, radio observations
  46. GRB991014 BATSE Observations
  47. GRB 991014, Optical Observations
  48. GRB 991014, optical observations
  49. Super-LOTIS optical observation of GRB991014
  50. IPN/NFI error box for GRB991014
  51. IPN localization of GRB991014 - CORRECTION
  52. IPN localization of GRB991014
  53. BeppoSAX ALERT: GRB991014
  54. GRB 990915 optical observations
  55. GRB 990907 optical observations
  56. BATSE GRB trigger criteria
  57. Optical Observations of GRB990907
  58. IPN error box for GRB990915 (=BATSE 7766)
  59. IPN localization of BATSE #7766 (GRB990915)
  60. IPN localization of GRB990907
  61. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  62. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  63. GRB 990712 Late Optical Decay and Host Galaxy
  64. GRB 990712, Optical Observation
  65. GRB990806: BATSE Observations
  66. GRB 990806 Optical observations
  67. Optical Observations of GRB990806
  68. GRB 990806, Optical Observations
  69. GRB 990806, optical observations
  70. GRB 990806, Optical Observations
  71. GRB990806 UBVRIJHK observations
  72. BeppoSAX ALERT GRB990806: Summer GRB
  73. GRB 990712 Optical Observations
  74. GRB990705: No Evidence for Neutrino Signal
  75. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  76. VLT spectrum of GRB990712
  77. GRB 990712
  78. Late-time HST/STIS Observations of GRB 990510
  79. Refined BeppoSAX-WFC position of GRB990712
  80. GRB 990705, R-band observations
  81. Updated IPN localization of GRB990705
  82. IPN localization of GRB990704
  83. IPN localization of GRB990705
  84. Infrared and Optical Observations of GRB990705
  85. GRB 990705, radio observations
  86. GRB990704 radio and optical observations
  87. GRB 990704 X-ray Observations
  88. GRB 990704 Optical Observations
  89. GRB 990704, optical observations
  90. GRB990704
  91. GRB990705: Intriguing Positional Coincidences
  92. GRB990704
  93. GRB990704, optical observations
  94. Identification of a possible optical counterpart for GRB990704
  95. GRB990704
  96. Refined BeppoSAX-WFC position of GRB990704
  97. GRB990704: BeppoSAX detection
  98. Optical Observations of GRB990627
  99. GRB 990627, radio observations
  100. GRB990627: BeppoSAX-WFC final location

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