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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"

22062 results found.

  1. Single IPN error box for GRB991229
  2. GRB 991216 VLBA Observations
  3. BEPPOSAX GRBM Localization of GRB991226
  4. IPN error boxes for GRB991229
  5. GRB 991216: J band spectrophotometry
  6. IPN localization of GRB991226
  7. Single IPN error box for GRB991221
  8. IPN error boxes for GRB991221
  9. GRB 991216 RXTE ASM Observations
  10. IPN error box for GRB991216
  11. Lowell/Perkins observation of GRB 991216
  12. GRB 991217 (SAX J2303.2+0015) Optical observations
  13. GRB991217/SAX J2303.2+0015, optical observations
  14. GRB 991216, optical observations
  15. GRB 991216 Optical Observations
  16. GRB991216 Optical and IR observations
  17. K observations of GRB991216
  18. SAX J2303.2+0015 Optical observations
  19. IR observations of GRB991216
  20. GRB991216 radio observations
  21. GRB 991217 (SAX J2303.2+0015) Optical observations
  22. GRB991216 radio observations
  23. GRB991216, optical observations
  24. GRB991216 Optical and infrared observations of Beethoven Burst
  25. GRB 991216 Radio Observations
  26. GRB 991208 Keck Spectroscopy
  27. GRB 991208 Infrared Detection
  28. GRB991216
  29. GRB 991216--Summary of RXTE Observations
  30. GRB 991216 Optical Observations
  31. GRB 991216, optical observations
  32. GRB 991216, Optical Transient
  33. GRB 991216, Optical Afterglow
  34. GRB991216 ('Beethoven Burst') B, R, and K Observations
  35. GRB991216, infrared observations
  36. GRB991216 Optical Observations
  37. GRB 991208 optical observations
  38. GRB 991208 Keck Spectroscopy
  39. GRB 991216: Extremely bright BATSE burst
  40. R-band Observations of GRB991208 at TNG
  41. GRB991208, optical observations
  42. GRB 991208 Keck Spectroscopy
  43. GRB991208 15-GHz observations
  44. GRB991208, optical observations
  45. GRB 991208 - OVRO detection
  46. GRB 991208 optical observations
  47. GRB 991208 optical observations
  48. GRB 991208: Radio Observations
  49. IPN localization of GRB991208
  50. Optical Observations of GRB991105
  51. GRB991106: BeppoSAX/BATSE results
  52. GRB 991106, optical observations
  53. GRB991106, near-infrared observations
  54. GRB 991106, radio observations
  55. GRB 991105: BATSE Observations
  56. IPN localization of GRB991105
  57. GRB 991106 Optical Observations
  58. GRB 991105, optical observations
  59. GRB 991106, LOTIS Optical Observations
  60. GRB 991106, optical observations
  61. GRB 991014, Optical Observations
  62. GRB 991014 - BeppoSAX NFI observations
  63. GRB 991014, Optical Observations
  64. GRB 991014, radio observations
  65. GRB991014 BATSE Observations
  66. GRB 991014, Optical Observations
  67. GRB 991014, optical observations
  68. GRB 990915 optical observations
  69. GRB 990907 optical observations
  70. Optical Observations of GRB990907
  71. IPN error box for GRB990915 (=BATSE 7766)
  72. GRB990907 and 990908
  73. GRB 990712 Late Optical Decay and Host Galaxy
  74. GRB 990712, Optical Observation
  75. GRB990806: BATSE Observations
  76. GRB 990806 Optical observations
  77. Optical Observations of GRB990806
  78. GRB 990806, Optical Observations
  79. GRB 990806, optical observations
  80. GRB 990806, Optical Observations
  81. GRB990806 UBVRIJHK observations
  82. GRB 990712 Optical Observations
  83. GRB 990712
  84. Late-time HST/STIS Observations of GRB 990510
  85. GRB 990705, R-band observations
  86. Updated IPN localization of GRB990705
  87. Infrared and Optical Observations of GRB990705
  88. GRB 990705, radio observations
  89. GRB990704 radio and optical observations
  90. BeppoSAX GRB990705: possible X-ray afterglow
  91. GRB 990704 X-ray Observations
  92. GRB 990704 Optical Observations
  93. GRB 990704, optical observations
  94. GRB990705: Intriguing Positional Coincidences
  95. GRB990704
  96. GRB990704, optical observations
  97. Identification of a possible optical counterpart for GRB990704
  98. GRB990704
  99. Optical Observations of GRB990627
  100. GRB 990627, radio observations

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