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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"

24664 results found.

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

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