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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"

39154 results found.

  1. GRB 991014, optical observations
  2. Super-LOTIS optical observation of GRB991014
  3. IPN/NFI error box for GRB991014
  4. IPN localization of GRB991014 - CORRECTION
  5. IPN localization of GRB991014
  6. BeppoSAX ALERT: GRB991014
  7. GRB 990915 optical observations
  8. GRB 990907 optical observations
  9. BATSE GRB trigger criteria
  10. Optical Observations of GRB990907
  11. IPN error box for GRB990915 (=BATSE 7766)
  12. IPN localization of BATSE #7766 (GRB990915)
  13. IPN localization of GRB990907
  14. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  15. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  16. GRB 990712 Late Optical Decay and Host Galaxy
  17. GRB 990712, Optical Observation
  18. GRB990806 BeppoSAX follow up
  19. GRB990806: BATSE Observations
  20. GRB 990806 Optical observations
  21. Optical Observations of GRB990806
  22. GRB 990806, Optical Observations
  23. GRB 990806, optical observations
  24. GRB 990806, Optical Observations
  25. GRB990806 UBVRIJHK observations
  26. BeppoSAX ALERT GRB990806: Summer GRB
  27. GRB 990712 Optical Observations
  28. GRB990705: No Evidence for Neutrino Signal
  29. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  30. VLT spectrum of GRB990712
  31. GRB 990712
  32. Late-time HST/STIS Observations of GRB 990510
  33. Refined BeppoSAX-WFC position of GRB990712
  34. GRB 990705, R-band observations
  35. Updated IPN localization of GRB990705
  36. IPN localization of GRB990704
  37. IPN localization of GRB990705
  38. Infrared and Optical Observations of GRB990705
  39. GRB 990705, radio observations
  40. GRB990704 radio and optical observations
  41. BeppoSAX GRB990705: possible X-ray afterglow
  42. GRB 990704 X-ray Observations
  43. GRB 990704 Optical Observations
  44. GRB 990704, optical observations
  45. GRB990704
  46. GRB990705: Intriguing Positional Coincidences
  47. GRB990704
  48. GRB990704, optical observations
  49. Identification of a possible optical counterpart for GRB990704
  50. GRB990704
  51. Refined BeppoSAX-WFC position of GRB990704
  52. GRB990704: BeppoSAX detection
  53. Optical Observations of GRB990627
  54. GRB 990627, radio observations
  55. GRB990627: BeppoSAX-WFC final location
  56. BeppoSAX: GRB990625
  57. Late-time HST/STIS Observation of GRB 990123
  58. GRB 990506 - clarification to GCN 352
  59. GRB 990506 - Optical Observations
  60. Optical Observations of GRB 990506
  61. GRB 990506 Radio Transient
  62. GRB990527 Optical Observations
  63. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  64. IPN error box for GRB990527
  65. Late Afterglows of GRBs 990510, 990123
  66. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  67. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  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. radio detection of X-ray/GRB transient
  78. BeppoSAX: A new fast X-ray transient
  79. GRB 990510: optical observations
  80. GRB990510: photometric and spectroscopic observations with the VLT
  81. GRB 990510: optical linear polarization
  82. GRB 990510: optical observations
  83. GRB990510, VI observations
  84. GRB 990506 R band observations
  85. GRB990510: X-ray afterglow
  86. GRB 990510: optical observation
  87. VLT spectrum of GRB990510
  88. GRB 990510: Broad Band Break
  89. GRB 990510: BATSE Observations
  90. GRB 990510 Optical Observations
  91. GRB 990510, BVI photometry
  92. GRB 990510 optical observations
  93. GRB 990510: BeppoSAX/GRBM observations
  94. GRB990510 optical observations
  95. GRB 990510 optical observations
  96. GRB 990510 optical observations
  97. Galactic extinction towards GRB 990510
  98. GRB 990510 optical observations
  99. IPN localization of GRB990510
  100. GRB 990506 Radio Observations

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