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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.

Advanced Search Examples (click to copy):

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

17213 results found.

  1. GRB991216, UBVRIJHK field photometry
  2. GCN resumes full operations
  3. GRB 991216: Detection of the Host and/or Absorber Galaxy
  4. GRB 991216 RXTE ASM Observations
  5. GRB 991217 (SAX J2303.2+0015) Optical observations
  6. Chandra observation of the X-ray afterglow of GRB991216
  7. SAX J2303.2+0015 Optical observations
  8. IR observations of GRB991216
  9. GRB 991217 (SAX J2303.2+0015) Optical observations
  10. GRB 991216 Radio Observations
  11. GRB 991208 Infrared Detection
  12. GRB991216
  13. GRB 991216--Summary of RXTE Observations
  14. GRB 991216 Optical Observations
  15. GRB 991216, optical observations
  16. GRB 991208 SAO-RAS Spectroscopy
  17. SAX J2303.2+0015: an x-ray/GRB?
  18. GRB 991216, Optical Transient
  19. GRB991216 ('Beethoven Burst') B, R, and K Observations
  20. GRB991216, infrared observations
  21. GRB 991208 optical observations
  22. GRB 991216 Optical Observation
  23. GRB 991216: Extremely bright BATSE burst
  24. R-band Observations of GRB991208 at TNG
  25. GRB991208, optical observations
  26. GRB 991208, Optical Observation
  27. GRB991208, optical observations
  28. IPN localization of GRB991208
  29. Optical Observations of GRB991105
  30. GRB991106: BeppoSAX/BATSE results
  31. BeppoSAX NFI Observation of GRB991106
  32. GRB 991106, radio observations
  33. GRB991106: the first BeppoSAX short GRB detection?
  34. GRB 991106 Optical Observations
  35. GRB991106, optical observation at SAO-RAS
  36. GRB 991106, LOTIS Optical Observations
  37. GRB991105: SAX-GRBM/-WFC detection
  38. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  39. GRB 991014, Optical Observations
  40. GRB 991014 - BeppoSAX NFI observations
  41. GRB 991014, radio observations
  42. GRB 991014, Optical Observations
  43. GRB 991014, optical observations
  44. Optical Observations of GRB990907
  45. GRB990907: BeppoSAX follow up and X-ray afterglow
  46. GRB990907 and 990908
  47. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  48. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  49. GRB990806 BeppoSAX follow up
  50. GRB 990806 Optical observations
  51. GRB 990806, optical observations
  52. GRB 990806, Optical Observations
  53. GRB990806: possible X-ray afterglow, BeppoSAX
  54. GRB 990712 Optical Observations
  55. GRB 990712
  56. Late-time HST/STIS Observations of GRB 990510
  57. BeppoSAX NFI Observation of GRB990705
  58. BeppoSAX NFI Observation of GRB990705
  59. GRB 990705, R-band observations
  60. GRB990704: SAX-NFI results summary
  61. GRB990704 radio and optical observations
  62. GRB990704
  63. GRB990704, optical observations
  64. GRB990704: possible X-ray afterglow
  65. GRB990704
  66. GRB990704: BeppoSAX detection
  67. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  68. GRB 990627, radio observations
  69. Late-time HST/STIS Observation of GRB 990123
  70. Optical Observations of GRB 990506
  71. GRB 990506 Radio Transient
  72. GRB990527 Optical Observations
  73. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  74. IPN error box for GRB990527
  75. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  76. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  77. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  78. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  79. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  80. radio observations of X-ray/GRB transient field
  81. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  82. Optical report on X-ray/GRB transient
  83. radio detection of X-ray/GRB transient
  84. GRB 990510: optical linear polarization
  85. GRB 990510: optical observations
  86. GRB990510: X-ray afterglow
  87. GRB 990510 optical observations
  88. GRB990510: NFI X-ray source
  89. GRB 990506 Radio Observations
  90. GRB 990123, optical monitoring
  91. GRB 990506, optical observations
  92. GRB 990510: Final BeppoSAX-WFC Coordinates
  93. GRB 990506, Optical Observations
  94. GRB 990506 optical observations
  95. GRB 990506 optical observations
  96. GRB 990506, optical observations
  97. GRB990506 observation plan
  98. GRB 990506, optical observations from +1 to +3 hours
  99. GRB 990506, optical observations
  100. GRB990506 observation plan

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