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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"

25989 results found.

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

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