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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"

24598 results found.

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

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