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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"

25992 results found.

  1. GRB000214 refined BeppoSAX-WFC position
  2. GRB 000210: BATSE Observations
  3. Optical observations of the Chandra X-ray source for GRB000210
  4. GRB000210, Radio Observations
  5. IPN triangulation of GRB000210
  6. GRB000210: possible afterglow detection with BeppoSAX NFI
  7. GRB000201, Radio Observations
  8. GRB000210: BeppoSAX GRBM and WFC Detection
  9. SAX_WFC_GRB_NOTICE
  10. SAX_WFC_GRB_NOTICE
  11. GRB000201 Optical Observations
  12. GRB 000201: TAROT optical observations
  13. GRB 991208, radio observations
  14. BATSE+IPN location of GRB000131
  15. IPN localization of GRB000131
  16. GRB 000126, optical observations
  17. BATSE Observations of GRB000115
  18. Second RXTE Observation of GRB 000115
  19. GRB991216, UBVRIJHK field photometry
  20. GCN resumes full operations
  21. GRB 991216 VLBA Observations
  22. GRB 991216: J band spectrophotometry
  23. GRB 991216: Detection of the Host and/or Absorber Galaxy
  24. IPN localization of GRB991226
  25. GRB 991216 RXTE ASM Observations
  26. GRB 991216: Updated BATSE parameters
  27. GRB 991217 (SAX J2303.2+0015) Optical observations
  28. Chandra observation of the X-ray afterglow of GRB991216
  29. GRB 991216, optical observations
  30. GRB 991216 Optical spectroscopy/imaging
  31. SAX J2303.2+0015 Optical observations
  32. IR observations of GRB991216
  33. GRB 991217 (SAX J2303.2+0015) Optical observations
  34. GRB991216 Optical and infrared observations of Beethoven Burst
  35. GRB 991216 Radio Observations
  36. GRB 991208 Keck Spectroscopy
  37. GRB 991208 Infrared Detection
  38. GRB991216
  39. GRB 991216--Summary of RXTE Observations
  40. GRB 991216 Optical Observations
  41. GRB 991216, optical observations
  42. GRB 991208 SAO-RAS Spectroscopy
  43. SAX J2303.2+0015: an x-ray/GRB?
  44. GRB 991216, Optical Transient
  45. GRB991216 ('Beethoven Burst') B, R, and K Observations
  46. GRB991216, infrared observations
  47. GRB 991208 optical observations
  48. GRB 991216 Optical Observation
  49. GRB 991216: Extremely bright BATSE burst
  50. R-band Observations of GRB991208 at TNG
  51. GRB991208, optical observations
  52. GRB 991208, Optical Observation
  53. GRB991208, optical observations
  54. GRB 991208 optical observations
  55. Optical Observations of GRB991105
  56. GRB991106: BeppoSAX/BATSE results
  57. GRB991106, near-infrared observations
  58. BeppoSAX NFI Observation of GRB991106
  59. GRB 991106, radio observations
  60. GRB991106: the first BeppoSAX short GRB detection?
  61. GRB 991105: BATSE Observations
  62. GRB 991106 Optical Observations
  63. GRB991106, optical observation at SAO-RAS
  64. GRB 991106, LOTIS Optical Observations
  65. GRB991105: SAX-GRBM/-WFC detection
  66. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  67. GRB 991014, Optical Observations
  68. GRB 991014 - BeppoSAX NFI observations
  69. GRB 991014, radio observations
  70. GRB 991014, Optical Observations
  71. GRB 991014, optical observations
  72. GRB 990915 optical observations
  73. Optical Observations of GRB990907
  74. GRB990907: BeppoSAX follow up and X-ray afterglow
  75. GRB990907 and 990908
  76. GRB 990712 Late Optical Decay and Host Galaxy
  77. GRB990806 BeppoSAX follow up
  78. GRB990806: BATSE Observations
  79. GRB 990806 Optical observations
  80. GRB 990806, Optical Observations
  81. GRB 990806, optical observations
  82. GRB 990806, Optical Observations
  83. GRB990806 UBVRIJHK observations
  84. GRB 990712 Optical Observations
  85. GRB 990712
  86. Late-time HST/STIS Observations of GRB 990510
  87. BeppoSAX NFI Observation of GRB990705
  88. BeppoSAX NFI Observation of GRB990705
  89. GRB 990705, R-band observations
  90. Infrared and Optical Observations of GRB990705
  91. GRB990704: SAX-NFI results summary
  92. GRB990704 radio and optical observations
  93. GRB990704
  94. GRB990704, optical observations
  95. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  96. Optical Observations of GRB990627
  97. BeppoSAX: GRB990625
  98. Late-time HST/STIS Observation of GRB 990123
  99. Optical Observations of GRB 990506
  100. GRB990527 Optical Observations

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