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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"

28711 results found.

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

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