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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"

26363 results found.

  1. GRB 991216 Optical spectroscopy/imaging
  2. SAX J2303.2+0015 Optical observations
  3. IR observations of GRB991216
  4. GRB 991217 (SAX J2303.2+0015) Optical observations
  5. GRB991216 Optical and infrared observations of Beethoven Burst
  6. GRB 991216 Radio Observations
  7. GRB 991208 Keck Spectroscopy
  8. GRB 991208 Infrared Detection
  9. GRB991216
  10. GRB 991216--Summary of RXTE Observations
  11. GRB 991216 Optical Observations
  12. GRB 991216, optical observations
  13. GRB 991208 SAO-RAS Spectroscopy
  14. SAX J2303.2+0015: an x-ray/GRB?
  15. GRB 991216, Optical Transient
  16. GRB991216 ('Beethoven Burst') B, R, and K Observations
  17. GRB991216, infrared observations
  18. GRB 991208 optical observations
  19. GRB 991216 Optical Observation
  20. GRB 991216: Extremely bright BATSE burst
  21. R-band Observations of GRB991208 at TNG
  22. GRB991208, optical observations
  23. GRB 991208, Optical Observation
  24. GRB991208, optical observations
  25. GRB 991208 optical observations
  26. Optical Observations of GRB991105
  27. GRB991106: BeppoSAX/BATSE results
  28. GRB991106, near-infrared observations
  29. BeppoSAX NFI Observation of GRB991106
  30. GRB 991106, radio observations
  31. GRB991106: the first BeppoSAX short GRB detection?
  32. GRB 991105: BATSE Observations
  33. GRB 991106 Optical Observations
  34. GRB991106, optical observation at SAO-RAS
  35. GRB 991106, LOTIS Optical Observations
  36. GRB991105: SAX-GRBM/-WFC detection
  37. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  38. GRB 991014, Optical Observations
  39. GRB 991014 - BeppoSAX NFI observations
  40. GRB 991014, radio observations
  41. GRB 991014, Optical Observations
  42. GRB 991014, optical observations
  43. GRB 990915 optical observations
  44. Optical Observations of GRB990907
  45. GRB990907: BeppoSAX follow up and X-ray afterglow
  46. GRB990907 and 990908
  47. GRB 990712 Late Optical Decay and Host Galaxy
  48. GRB990806 BeppoSAX follow up
  49. GRB990806: BATSE Observations
  50. GRB 990806 Optical observations
  51. GRB 990806, Optical Observations
  52. GRB 990806, optical observations
  53. GRB 990806, Optical Observations
  54. GRB990806 UBVRIJHK observations
  55. GRB 990712 Optical Observations
  56. GRB 990712
  57. Late-time HST/STIS Observations of GRB 990510
  58. BeppoSAX NFI Observation of GRB990705
  59. BeppoSAX NFI Observation of GRB990705
  60. GRB 990705, R-band observations
  61. Infrared and Optical Observations of GRB990705
  62. GRB990704: SAX-NFI results summary
  63. GRB990704 radio and optical observations
  64. GRB990704
  65. GRB990704, optical observations
  66. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  67. Optical Observations of GRB990627
  68. BeppoSAX: GRB990625
  69. Late-time HST/STIS Observation of GRB 990123
  70. Optical Observations of GRB 990506
  71. GRB990527 Optical Observations
  72. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  73. Late Afterglows of GRBs 990510, 990123
  74. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  75. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  76. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  77. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  78. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  79. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  80. radio observations of X-ray/GRB transient field
  81. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  82. Optical report on X-ray/GRB transient
  83. radio detection of X-ray/GRB transient
  84. BeppoSAX: A new fast X-ray transient
  85. GRB 990510: optical observations
  86. GRB 990510: optical linear polarization
  87. GRB 990510: optical observations
  88. GRB990510: X-ray afterglow
  89. GRB 990510: Broad Band Break
  90. GRB 990510: BATSE Observations
  91. GRB 990510: BeppoSAX/GRBM observations
  92. GRB990510 optical observations
  93. GRB 990510 optical observations
  94. GRB 990506 Radio Observations
  95. GRB 990123, optical monitoring
  96. GRB 990506: BATSE Observations
  97. GRB 990506, optical observations
  98. GRB 990506, Optical Observations
  99. GRB 990506 optical observations
  100. GRB 990506, optical observations

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