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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"

41191 results found.

  1. IPN localization of GRB991014
  2. BeppoSAX ALERT: GRB991014
  3. GRB 990915 optical observations
  4. GRB 990907 optical observations
  5. Optical Observations of GRB990907
  6. GRB990907: BeppoSAX follow up and X-ray afterglow
  7. GRB990907 and 990908
  8. IPN localization of GRB990907
  9. GRB990907: refined WFC position
  10. GRB 990712 Late Optical Decay and Host Galaxy
  11. GRB 990712, Optical Observation
  12. GRB990806 BeppoSAX follow up
  13. GRB990806: BATSE Observations
  14. GRB 990806 Optical observations
  15. Optical Observations of GRB990806
  16. GRB 990806, Optical Observations
  17. GRB 990806, optical observations
  18. GRB 990806, Optical Observations
  19. GRB990806 UBVRIJHK observations
  20. GRB990806: possible X-ray afterglow, BeppoSAX
  21. BeppoSAX ALERT GRB990806: Summer GRB
  22. GRB 990712 Optical Observations
  23. GRB990705: No Evidence for Neutrino Signal
  24. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  25. VLT spectrum of GRB990712
  26. GRB 990712
  27. Late-time HST/STIS Observations of GRB 990510
  28. Refined BeppoSAX-WFC position of GRB990712
  29. GRB 990705, R-band observations
  30. Updated IPN localization of GRB990705
  31. IPN localization of GRB990704
  32. Infrared and Optical Observations of GRB990705
  33. GRB 990705, radio observations
  34. GRB990704 radio and optical observations
  35. GRB 990704 X-ray Observations
  36. GRB 990704 Optical Observations
  37. GRB 990704, optical observations
  38. GRB990704
  39. GRB990705: Intriguing Positional Coincidences
  40. GRB990704
  41. GRB990704, optical observations
  42. Identification of a possible optical counterpart for GRB990704
  43. GRB990704
  44. Refined BeppoSAX-WFC position of GRB990704
  45. GRB990704: BeppoSAX detection
  46. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  47. Optical Observations of GRB990627
  48. GRB 990627, radio observations
  49. BeppoSAX: GRB990625
  50. Late-time HST/STIS Observation of GRB 990123
  51. GRB 990506 - clarification to GCN 352
  52. GRB 990506 - Optical Observations
  53. Optical Observations of GRB 990506
  54. GRB 990506 Radio Transient
  55. GRB990527 Optical Observations
  56. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  57. IPN error box for GRB990527
  58. Late Afterglows of GRBs 990510, 990123
  59. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  60. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  62. GRB 990506 optical observation
  63. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  64. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  65. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  67. radio observations of X-ray/GRB transient field
  68. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  69. Optical report on X-ray/GRB transient
  70. BeppoSAX: A new fast X-ray transient
  71. GRB 990510: optical observations
  72. GRB990510: photometric and spectroscopic observations with the VLT
  73. GRB 990510: optical linear polarization
  74. GRB 990510: optical observations
  75. GRB990510, VI observations
  76. GRB 990506 R band observations
  77. GRB990510: X-ray afterglow
  78. GRB 990510: optical observation
  79. VLT spectrum of GRB990510
  80. GRB 990510: Broad Band Break
  81. GRB 990510: BATSE Observations
  82. GRB990510: optical observation
  83. GRB 990510 Optical Observations
  84. GRB 990510, BVI photometry
  85. GRB 990510 optical observations
  86. GRB 990510: BeppoSAX/GRBM observations
  87. GRB990510 optical observations
  88. GRB990510
  89. GRB 990510 optical observations
  90. GRB 990510 optical observations
  91. Galactic extinction towards GRB 990510
  92. GRB 990510 optical observations
  93. IPN localization of GRB990510
  94. GRB 990123, optical monitoring
  95. GRB 990506: BATSE Observations
  96. GRB 990506, optical observations
  97. GRB 990510: Final BeppoSAX-WFC Coordinates
  98. GRB 990506, Optical Observations
  99. GRB 990506 optical observations
  100. GRB 990506 optical observations

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