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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"

24888 results found.

  1. IPN triangulation of GRB000210
  2. GRB000210: possible afterglow detection with BeppoSAX NFI
  3. GRB000201, Radio Observations
  4. GRB000210: BeppoSAX GRBM and WFC Detection
  5. SAX_WFC_GRB_NOTICE
  6. SAX_WFC_GRB_NOTICE
  7. GRB000201 Optical Observations
  8. GRB 000201: TAROT optical observations
  9. GRB 991208, radio observations
  10. BATSE+IPN location of GRB000131
  11. IPN localization of GRB000131
  12. GRB 000126, optical observations
  13. BATSE Observations of GRB000115
  14. Second RXTE Observation of GRB 000115
  15. GRB991216, UBVRIJHK field photometry
  16. GCN resumes full operations
  17. GRB 991216 VLBA Observations
  18. GRB 991216: J band spectrophotometry
  19. GRB 991216: Detection of the Host and/or Absorber Galaxy
  20. IPN localization of GRB991226
  21. GRB 991216 RXTE ASM Observations
  22. GRB 991216: Updated BATSE parameters
  23. GRB 991217 (SAX J2303.2+0015) Optical observations
  24. Chandra observation of the X-ray afterglow of GRB991216
  25. GRB 991216, optical observations
  26. GRB 991216 Optical spectroscopy/imaging
  27. SAX J2303.2+0015 Optical observations
  28. IR observations of GRB991216
  29. GRB 991217 (SAX J2303.2+0015) Optical observations
  30. GRB991216 Optical and infrared observations of Beethoven Burst
  31. GRB 991216 Radio Observations
  32. GRB 991208 Keck Spectroscopy
  33. GRB 991208 Infrared Detection
  34. GRB991216
  35. GRB 991216--Summary of RXTE Observations
  36. GRB 991216 Optical Observations
  37. GRB 991216, optical observations
  38. GRB 991208 SAO-RAS Spectroscopy
  39. SAX J2303.2+0015: an x-ray/GRB?
  40. GRB 991216, Optical Transient
  41. GRB991216 ('Beethoven Burst') B, R, and K Observations
  42. GRB991216, infrared observations
  43. GRB 991208 optical observations
  44. GRB 991216 Optical Observation
  45. GRB 991216: Extremely bright BATSE burst
  46. R-band Observations of GRB991208 at TNG
  47. GRB991208, optical observations
  48. GRB 991208, Optical Observation
  49. GRB991208, optical observations
  50. GRB 991208 optical observations
  51. Optical Observations of GRB991105
  52. GRB991106: BeppoSAX/BATSE results
  53. GRB991106, near-infrared observations
  54. BeppoSAX NFI Observation of GRB991106
  55. GRB 991106, radio observations
  56. GRB991106: the first BeppoSAX short GRB detection?
  57. GRB 991105: BATSE Observations
  58. GRB 991106 Optical Observations
  59. GRB991106, optical observation at SAO-RAS
  60. GRB 991106, LOTIS Optical Observations
  61. GRB991105: SAX-GRBM/-WFC detection
  62. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  63. GRB 991014, Optical Observations
  64. GRB 991014 - BeppoSAX NFI observations
  65. GRB 991014, radio observations
  66. GRB 991014, Optical Observations
  67. GRB 991014, optical observations
  68. GRB 990915 optical observations
  69. Optical Observations of GRB990907
  70. GRB990907: BeppoSAX follow up and X-ray afterglow
  71. GRB990907 and 990908
  72. GRB 990712 Late Optical Decay and Host Galaxy
  73. GRB990806 BeppoSAX follow up
  74. GRB990806: BATSE Observations
  75. GRB 990806 Optical observations
  76. GRB 990806, Optical Observations
  77. GRB 990806, optical observations
  78. GRB 990806, Optical Observations
  79. GRB990806 UBVRIJHK observations
  80. GRB 990712 Optical Observations
  81. GRB 990712
  82. Late-time HST/STIS Observations of GRB 990510
  83. BeppoSAX NFI Observation of GRB990705
  84. BeppoSAX NFI Observation of GRB990705
  85. GRB 990705, R-band observations
  86. Infrared and Optical Observations of GRB990705
  87. GRB990704: SAX-NFI results summary
  88. GRB990704 radio and optical observations
  89. GRB990704
  90. GRB990704, optical observations
  91. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  92. Optical Observations of GRB990627
  93. BeppoSAX: GRB990625
  94. Late-time HST/STIS Observation of GRB 990123
  95. Optical Observations of GRB 990506
  96. GRB990527 Optical Observations
  97. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  98. Late Afterglows of GRBs 990510, 990123
  99. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  100. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation

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