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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').

32051 results found.

  1. GRB 000115, BVRI field photometry
  2. IPN annulus for GRB000214
  3. BATSE GRB trigger criterion changed
  4. GRB000210 X-ray afterglow
  5. GRB000214: X-ray afterglow candidate
  6. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  7. GRB 000210: BATSE Observations
  8. Optical observations of the Chandra X-ray source for GRB000210
  9. Chandra Observations of GRB000210 X-ray Afterglow
  10. IPN triangulation of GRB000210
  11. GRB 000201: TAROT optical observations
  12. GRB 000131 Optical Observations
  13. GRB000126 Optical Observations
  14. BATSE GRB trigger criteria changed
  15. GRB 991208, radio observations
  16. BATSE+IPN location of GRB000131
  17. IPN localization of GRB000131
  18. GRB 000126, optical observations
  19. GRB000126, optical observations
  20. BATSE location of GRB000126
  21. IPN localization of GRB000126
  22. GRB 000115 Optical observations
  23. BATSE Observations of GRB000115
  24. Second RXTE Observation of GRB 000115
  25. GRB991216, UBVRIJHK field photometry
  26. Single IPN error box for GRB991229
  27. GRB 991216 VLBA Observations
  28. BEPPOSAX GRBM Localization of GRB991226
  29. IPN error boxes for GRB991229
  30. GRB 991216: J band spectrophotometry
  31. GRB 991216: Detection of the Host and/or Absorber Galaxy
  32. IPN localization of GRB991226
  33. Single IPN error box for GRB991221
  34. IPN error boxes for GRB991221
  35. GRB 991216 RXTE ASM Observations
  36. IPN error box for GRB991216
  37. GRB 991216: Updated BATSE parameters
  38. Lowell/Perkins observation of GRB 991216
  39. GRB 991217 (SAX J2303.2+0015) Optical observations
  40. Chandra observation of the X-ray afterglow of GRB991216
  41. GRB 991216, optical observations
  42. GRB 991216 Optical Observations
  43. GRB 991216 Optical spectroscopy/imaging
  44. VLT spectra of GRB991216
  45. K observations of GRB991216
  46. GRB 991217 (SAX J2303.2+0015) Optical observations
  47. GRB991216 Spectroscopy
  48. Lowell/Perkins observation of GRB 991216
  49. GRB991216, optical observations
  50. Refined IPN localization of GRB991216
  51. GRB 991216 Radio Observations
  52. GRB 991217
  53. GRB 991208 Keck Spectroscopy
  54. GRB 991208 Infrared Detection
  55. GRB 991216--Summary of RXTE Observations
  56. GRB 991216 Optical Observations
  57. GRB 991216, optical observations
  58. GRB 991208 SAO-RAS Spectroscopy
  59. SAX J2303.2+0015: an x-ray/GRB?
  60. GRB 991216, Optical Transient
  61. GRB 991216, Optical Afterglow
  62. GRB 991216: Comparison with DPOSS images
  63. GRB 991208 optical observations
  64. Lowell/Perkins observation of GRB 991216
  65. GRB 991216 Optical Observation
  66. GRB 991208 Keck Spectroscopy
  67. GRB 991216: Extremely bright BATSE burst
  68. GRB991208, optical observations
  69. GRB 991208 Keck Spectroscopy
  70. GRB991208 - millimeter detection
  71. GRB 991208, Optical Observation
  72. GRB 991208 - OVRO detection
  73. GRB 991208 Optical Decay
  74. GRB 991208 optical observations
  75. GRB 991208 optical observations
  76. GRB 991208: Radio Observations
  77. IPN localization of GRB991208
  78. Optical Observations of GRB991105
  79. GRB991106: BeppoSAX/BATSE results
  80. GRB 991106, optical observations
  81. GRB991106, near-infrared observations
  82. BeppoSAX NFI Observation of GRB991106
  83. GRB 991106, radio observations
  84. GRB991106: the first BeppoSAX short GRB detection?
  85. GRB 991105: BATSE Observations
  86. IPN localization of GRB991105
  87. GRB 991106 Optical Observations
  88. GRB 991105, optical observations
  89. GRB991106, optical observation at SAO-RAS
  90. GRB 991106, LOTIS Optical Observations
  91. GRB 991106, optical observations
  92. BeppoSAX GRB Alert: GRB991106
  93. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  94. GRB ALERT: GRB991105
  95. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  96. GRB 991014, Optical Observations
  97. GRB 991014 - BeppoSAX NFI observations
  98. GRB 991014, Optical Observations
  99. GRB 991014, radio observations
  100. GRB991014 BATSE Observations

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