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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"

31728 results found.

  1. GRB991208, optical observations
  2. GRB 991208 - OVRO detection
  3. GRB 991208 Optical Decay
  4. GRB 991208 optical observations
  5. GRB 991208 optical observations
  6. GRB 991208: Radio Observations
  7. Optical Observations of GRB991105
  8. GRB991106: BeppoSAX/BATSE results
  9. GRB 991106, optical observations
  10. GRB991106, near-infrared observations
  11. BeppoSAX NFI Observation of GRB991106
  12. GRB 991106, radio observations
  13. GRB 991105: BATSE Observations
  14. IPN localization of GRB991105
  15. GRB 991106 Optical Observations
  16. GRB 991105, optical observations
  17. GRB991106, optical observation at SAO-RAS
  18. GRB 991106, LOTIS Optical Observations
  19. GRB 991106, optical observations
  20. Revised BeppoSAX WFC position of GRB991105
  21. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  22. GRB 991014, Optical Observations
  23. GRB 991014 - BeppoSAX NFI observations
  24. GRB 991014, Optical Observations
  25. GRB 991014, Optical Observations
  26. GRB 991014, optical observations
  27. Super-LOTIS optical observation of GRB991014
  28. IPN/NFI error box for GRB991014
  29. IPN localization of GRB991014 - CORRECTION
  30. IPN localization of GRB991014
  31. GRB 990915 optical observations
  32. GRB 990907 optical observations
  33. Optical Observations of GRB990907
  34. IPN error box for GRB990915 (=BATSE 7766)
  35. IPN localization of BATSE #7766 (GRB990915)
  36. GRB990907: BeppoSAX follow up and X-ray afterglow
  37. GRB990907 and 990908
  38. IPN localization of GRB990907
  39. GRB 990712 Late Optical Decay and Host Galaxy
  40. GRB 990712, Optical Observation
  41. GRB990806 BeppoSAX follow up
  42. GRB990806: BATSE Observations
  43. GRB 990806 Optical observations
  44. Optical Observations of GRB990806
  45. GRB 990806, Optical Observations
  46. GRB 990806, optical observations
  47. GRB 990806, Optical Observations
  48. GRB990806 UBVRIJHK observations
  49. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  50. VLT spectrum of GRB990712
  51. GRB 990712
  52. Late-time HST/STIS Observations of GRB 990510
  53. BeppoSAX NFI Observation of GRB990705
  54. BeppoSAX NFI Observation of GRB990705
  55. Updated Astrometry for the IR Counterpart of GRB990705
  56. GRB 990705, R-band observations
  57. Updated IPN localization of GRB990705
  58. IPN localization of GRB990704
  59. IPN localization of GRB990705
  60. Infrared and Optical Observations of GRB990705
  61. GRB 990705, radio observations
  62. GRB990704: SAX-NFI results summary
  63. GRB990704 radio and optical observations
  64. GRB 990704 X-ray Observations
  65. GRB 990704 Optical Observations
  66. GRB 990704, optical observations
  67. GRB990704
  68. GRB990704
  69. Refined BeppoSAX-WFC position of GRB990704: Errata Corrige
  70. GRB990704, optical observations
  71. GRB990704: possible X-ray afterglow
  72. Identification of a possible optical counterpart for GRB990704
  73. GRB990704
  74. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  75. Optical Observations of GRB990627
  76. GRB 990627, radio observations
  77. GRB990627: BeppoSAX-WFC final location
  78. GRB 990506 - clarification to GCN 352
  79. GRB 990506 - Optical Observations
  80. Optical Observations of GRB 990506
  81. GRB 990506 Radio Transient
  82. GRB990527 Optical Observations
  83. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  84. Late Afterglows of GRBs 990510, 990123
  85. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  86. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  87. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  88. GRB 990506 optical observation
  89. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  90. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  91. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  92. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  93. radio observations of X-ray/GRB transient field
  94. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  95. Optical report on X-ray/GRB transient
  96. radio detection of X-ray/GRB transient
  97. BeppoSAX: A new fast X-ray transient
  98. GRB 990510: optical observations
  99. GRB990510, VI observations
  100. GRB 990506 R band observations

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