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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"

15985 results found.

  1. GRB 991208 Infrared Detection
  2. GRB 991216--Summary of RXTE Observations
  3. GRB 991216 Optical Observations
  4. GRB 991216, optical observations
  5. GRB 991208 SAO-RAS Spectroscopy
  6. GRB 991216, Optical Transient
  7. GRB 991216, Optical Afterglow
  8. GRB991216 ('Beethoven Burst') B, R, and K Observations
  9. GRB991216 Optical Observations
  10. GRB 991208 optical observations
  11. Lowell/Perkins observation of GRB 991216
  12. GRB 991216 Optical Observation
  13. GRB 991208 Keck Spectroscopy
  14. R-band Observations of GRB991208 at TNG
  15. GRB991208, optical observations
  16. GRB 991208, Optical Observation
  17. GRB991208, optical observations
  18. GRB 991208 Optical Decay
  19. GRB 991208 optical observations
  20. GRB 991208 optical observations
  21. GRB 991208: Radio Observations
  22. Optical Observations of GRB991105
  23. GRB 991106, optical observations
  24. GRB 991106 Optical Observations
  25. GRB 991105, optical observations
  26. GRB991106, optical observation at SAO-RAS
  27. GRB 991106, LOTIS Optical Observations
  28. GRB 991106, optical observations
  29. GRB 991014, Optical Observations
  30. GRB 991014, Optical Observations
  31. GRB 991014, Optical Observations
  32. GRB 991014, optical observations
  33. Super-LOTIS optical observation of GRB991014
  34. GRB 990915 optical observations
  35. GRB 990907 optical observations
  36. Optical Observations of GRB990907
  37. GRB 990712 Late Optical Decay and Host Galaxy
  38. GRB 990712, Optical Observation
  39. GRB 990806 Optical observations
  40. Optical Observations of GRB990806
  41. GRB 990806, Optical Observations
  42. GRB 990806, optical observations
  43. GRB 990806, Optical Observations
  44. GRB990806 UBVRIJHK observations
  45. GRB 990712 Optical Observations
  46. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  47. VLT spectrum of GRB990712
  48. GRB 990712
  49. GRB 990705, R-band observations
  50. IPN localization of GRB990704
  51. Infrared and Optical Observations of GRB990705
  52. GRB990704 radio and optical observations
  53. GRB 990704 Optical Observations
  54. GRB 990704, optical observations
  55. GRB990704
  56. GRB990704
  57. GRB990704, optical observations
  58. Identification of a possible optical counterpart for GRB990704
  59. GRB990704
  60. Optical Observations of GRB990627
  61. Late-time HST/STIS Observation of GRB 990123
  62. GRB 990506 - Optical Observations
  63. Optical Observations of GRB 990506
  64. GRB 990506 Radio Transient
  65. GRB990527 Optical Observations
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  67. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  68. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  69. GRB 990506 optical observation
  70. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  71. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  72. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  73. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  74. radio observations of X-ray/GRB transient field
  75. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  76. Optical report on X-ray/GRB transient
  77. GRB 990510: optical observations
  78. GRB990510: photometric and spectroscopic observations with the VLT
  79. GRB 990510: optical linear polarization
  80. GRB 990510: optical observations
  81. GRB990510, VI observations
  82. GRB 990506 R band observations
  83. GRB990510: X-ray afterglow
  84. GRB 990510: optical observation
  85. VLT spectrum of GRB990510
  86. GRB 990510: Broad Band Break
  87. GRB 990510: BATSE Observations
  88. GRB990510: optical observation
  89. GRB 990510 Optical Observations
  90. GRB 990510, BVI photometry
  91. GRB 990510 optical observations
  92. GRB990510 optical observations
  93. GRB990510
  94. GRB 990510 optical observations
  95. GRB 990510 optical observations
  96. Galactic extinction towards GRB 990510
  97. GRB 990510 optical observations
  98. GRB 990123, optical monitoring
  99. GRB 990506, optical observations
  100. GRB 990506, Optical Observations

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