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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"

27396 results found.

  1. GRB000214: BeppoSAX GRBM and WFC Detection
  2. Optical observations of GRB000210
  3. GRB000210 X-ray afterglow
  4. GRB000214: X-ray afterglow candidate
  5. GRB000214 refined BeppoSAX-WFC position
  6. GRB 000210: BATSE Observations
  7. Optical observations of the Chandra X-ray source for GRB000210
  8. GRB000210, Radio Observations
  9. IPN triangulation of GRB000210
  10. GRB000210: possible afterglow detection with BeppoSAX NFI
  11. GRB000201, Radio Observations
  12. GRB000210: BeppoSAX GRBM and WFC Detection
  13. SAX_WFC_GRB_NOTICE
  14. SAX_WFC_GRB_NOTICE
  15. GRB000201 Optical Observations
  16. GRB 000201: TAROT optical observations
  17. GRB 991208, radio observations
  18. BATSE+IPN location of GRB000131
  19. IPN localization of GRB000131
  20. GRB 000126, optical observations
  21. BATSE Observations of GRB000115
  22. Second RXTE Observation of GRB 000115
  23. GRB991216, UBVRIJHK field photometry
  24. GCN resumes full operations
  25. GRB 991216 VLBA Observations
  26. GRB 991216: J band spectrophotometry
  27. GRB 991216: Detection of the Host and/or Absorber Galaxy
  28. IPN localization of GRB991226
  29. GRB 991216 RXTE ASM Observations
  30. GRB 991216: Updated BATSE parameters
  31. GRB 991217 (SAX J2303.2+0015) Optical observations
  32. Chandra observation of the X-ray afterglow of GRB991216
  33. GRB 991216, optical observations
  34. GRB 991216 Optical spectroscopy/imaging
  35. SAX J2303.2+0015 Optical observations
  36. IR observations of GRB991216
  37. GRB 991217 (SAX J2303.2+0015) Optical observations
  38. GRB991216 Optical and infrared observations of Beethoven Burst
  39. GRB 991216 Radio Observations
  40. GRB 991208 Keck Spectroscopy
  41. GRB 991208 Infrared Detection
  42. GRB991216
  43. GRB 991216--Summary of RXTE Observations
  44. GRB 991216 Optical Observations
  45. GRB 991216, optical observations
  46. GRB 991208 SAO-RAS Spectroscopy
  47. SAX J2303.2+0015: an x-ray/GRB?
  48. GRB 991216, Optical Transient
  49. GRB991216 ('Beethoven Burst') B, R, and K Observations
  50. GRB991216, infrared observations
  51. GRB 991208 optical observations
  52. GRB 991216 Optical Observation
  53. GRB 991216: Extremely bright BATSE burst
  54. R-band Observations of GRB991208 at TNG
  55. GRB991208, optical observations
  56. GRB 991208, Optical Observation
  57. GRB991208, optical observations
  58. GRB 991208 optical observations
  59. Optical Observations of GRB991105
  60. GRB991106: BeppoSAX/BATSE results
  61. GRB991106, near-infrared observations
  62. BeppoSAX NFI Observation of GRB991106
  63. GRB 991106, radio observations
  64. GRB991106: the first BeppoSAX short GRB detection?
  65. GRB 991105: BATSE Observations
  66. GRB 991106 Optical Observations
  67. GRB991106, optical observation at SAO-RAS
  68. GRB 991106, LOTIS Optical Observations
  69. GRB991105: SAX-GRBM/-WFC detection
  70. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  71. GRB 991014, Optical Observations
  72. GRB 991014 - BeppoSAX NFI observations
  73. GRB 991014, radio observations
  74. GRB 991014, Optical Observations
  75. GRB 991014, optical observations
  76. GRB 990915 optical observations
  77. Optical Observations of GRB990907
  78. GRB990907: BeppoSAX follow up and X-ray afterglow
  79. GRB990907 and 990908
  80. GRB 990712 Late Optical Decay and Host Galaxy
  81. GRB990806 BeppoSAX follow up
  82. GRB990806: BATSE Observations
  83. GRB 990806 Optical observations
  84. GRB 990806, Optical Observations
  85. GRB 990806, optical observations
  86. GRB 990806, Optical Observations
  87. GRB990806 UBVRIJHK observations
  88. GRB 990712 Optical Observations
  89. GRB 990712
  90. Late-time HST/STIS Observations of GRB 990510
  91. BeppoSAX NFI Observation of GRB990705
  92. BeppoSAX NFI Observation of GRB990705
  93. GRB 990705, R-band observations
  94. Infrared and Optical Observations of GRB990705
  95. GRB990704: SAX-NFI results summary
  96. GRB990704 radio and optical observations
  97. GRB990704
  98. GRB990704, optical observations
  99. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  100. Optical Observations of GRB990627

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