Transcript Проект DANSS и проблема потоков реакторных антинейтрино

«Проект DANSS и проблема
потоков реакторных
антинейтрино»
А.Г.Ольшевский, ОИЯИ
Марковские чтения, 13 мая 2011
План выступления
 Введение
 Новые расчеты и аномалия
 Возможные проверки
 Проект DANSS
 Заключение
Осцилляции нейтрино
Солнечные
Атмосферные
Реакторные
Ускорительные
LEP results
HARP
Reactor Data
= 0.98 ± 0.03
R=0.86 ± 0.05
Test at Reactors
DANSS
detector of the reactor antineutrino
To be operated at Kalinin Power Plant
ITEP-JINR Collaboration
• GEMMA experiment: search for the NMM
• Since 2005 we do NMM measurements
under the unit #2 of the KNPP – a standard
3GWth PWR (ВВЭР-1000)
• Life-time ~ 320 days
• 1500 kg of 235U is burned out
• and 311 kg of 239Pu is produced
• which changes the flux and energy
spectrum of the neutrino emitted
• Would like to monitor the neutrino spectrum
and flux (2.7∙1013 /cm2/s)
Gd-containing
light-reflecting
coating
Polystyrenebased
scintillator
3 wave-length
shifting (WLS)
fibers Ø1.2 mm
1000
0.15
0.30
10
40
Basic element –
- scintillator cell (“strip” )
4.1 m
Lifting mechanism
DANSS features
 Position at short (~10m) distance from the core at
industrial power plant (~10000ev/day)
 High segmentation allows differential calibration to
improve energy resolution and event purity
 Measurement at different distances (change by ~2m)
Искажение спектров и оптимальные расстояния
1.04
11 м,
1.02
16 м,
p ( E)
p2 ( E)
Dm2 = 0.9 eV2,
1
16/11
t ( E)
0.98
sin22q = 0.04
Без учета
конечных
размеров АЗ
0.96
1
2
3
4
5
6
7
8
9
10
E
Энергия антинейтрино,
МэВ
В.В. Синев1, А.С. Старостин2
1 Институт Ядерных
2 Институт Теоретической
Исследований РАН,
и Экспериментальной Физики
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Conclusions
 New calculations of the reactor (anti)neutrino fluxes
highlighted the problem of the flux deficit
 Possible explanation of this deficit - the short distance
oscillations to sterile neutrino - is also considered to
explain LSND, MINIBOONE and Ga Calibration anomalies
 DANSS experiment which is build by ITEP/JINR
collaboration to operate at KPP can contribute to resolve
this problem by measuring antineutrino fluxes and spectra
at different (short) distances