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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"

24594 results found.

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

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