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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

33708 results found.

  1. VLT spectra of GRB991216
  2. K observations of GRB991216
  3. GRB 991217 (SAX J2303.2+0015) Optical observations
  4. GRB991216 Spectroscopy
  5. Lowell/Perkins observation of GRB 991216
  6. GRB991216, optical observations
  7. Refined IPN localization of GRB991216
  8. GRB 991216 Radio Observations
  9. GRB 991217
  10. GRB 991208 Keck Spectroscopy
  11. GRB 991208 Infrared Detection
  12. GRB 991216--Summary of RXTE Observations
  13. GRB 991216 Optical Observations
  14. GRB 991216, optical observations
  15. GRB 991208 SAO-RAS Spectroscopy
  16. SAX J2303.2+0015: an x-ray/GRB?
  17. GRB 991216, Optical Transient
  18. GRB 991216, Optical Afterglow
  19. GRB 991216: Comparison with DPOSS images
  20. GRB 991208 optical observations
  21. Lowell/Perkins observation of GRB 991216
  22. GRB 991216 Optical Observation
  23. GRB 991208 Keck Spectroscopy
  24. GRB 991216: Extremely bright BATSE burst
  25. GRB991208, optical observations
  26. GRB 991208 Keck Spectroscopy
  27. GRB991208 - millimeter detection
  28. GRB 991208, Optical Observation
  29. GRB 991208 - OVRO detection
  30. GRB 991208 Optical Decay
  31. GRB 991208 optical observations
  32. GRB 991208 optical observations
  33. GRB 991208: Radio Observations
  34. IPN localization of GRB991208
  35. Optical Observations of GRB991105
  36. GRB991106: BeppoSAX/BATSE results
  37. GRB 991106, optical observations
  38. GRB991106, near-infrared observations
  39. BeppoSAX NFI Observation of GRB991106
  40. GRB 991106, radio observations
  41. GRB991106: the first BeppoSAX short GRB detection?
  42. GRB 991105: BATSE Observations
  43. IPN localization of GRB991105
  44. GRB 991106 Optical Observations
  45. GRB 991105, optical observations
  46. GRB991106, optical observation at SAO-RAS
  47. GRB 991106, LOTIS Optical Observations
  48. GRB 991106, optical observations
  49. BeppoSAX GRB Alert: GRB991106
  50. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  51. GRB ALERT: GRB991105
  52. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  53. GRB 991014, Optical Observations
  54. GRB 991014 - BeppoSAX NFI observations
  55. GRB 991014, Optical Observations
  56. GRB 991014, radio observations
  57. GRB991014 BATSE Observations
  58. GRB 991014, Optical Observations
  59. GRB 991014, optical observations
  60. Super-LOTIS optical observation of GRB991014
  61. IPN/NFI error box for GRB991014
  62. IPN localization of GRB991014 - CORRECTION
  63. IPN localization of GRB991014
  64. BeppoSAX ALERT: GRB991014
  65. GRB 990915 optical observations
  66. GRB 990907 optical observations
  67. BATSE GRB trigger criteria
  68. Optical Observations of GRB990907
  69. IPN error box for GRB990915 (=BATSE 7766)
  70. IPN localization of BATSE #7766 (GRB990915)
  71. IPN localization of GRB990907
  72. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  73. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  74. GRB 990712 Late Optical Decay and Host Galaxy
  75. GRB 990712, Optical Observation
  76. GRB990806: BATSE Observations
  77. GRB 990806 Optical observations
  78. Optical Observations of GRB990806
  79. GRB 990806, Optical Observations
  80. GRB 990806, optical observations
  81. GRB 990806, Optical Observations
  82. GRB990806 UBVRIJHK observations
  83. BeppoSAX ALERT GRB990806: Summer GRB
  84. GRB 990712 Optical Observations
  85. GRB990705: No Evidence for Neutrino Signal
  86. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  87. VLT spectrum of GRB990712
  88. GRB 990712
  89. Late-time HST/STIS Observations of GRB 990510
  90. Refined BeppoSAX-WFC position of GRB990712
  91. GRB 990705, R-band observations
  92. Updated IPN localization of GRB990705
  93. IPN localization of GRB990704
  94. IPN localization of GRB990705
  95. Infrared and Optical Observations of GRB990705
  96. GRB 990705, radio observations
  97. GRB990704 radio and optical observations
  98. GRB 990704 X-ray Observations
  99. GRB 990704 Optical Observations
  100. GRB 990704, optical observations

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