粒子物理规划及未来的中微子实验

1、粒子物理规划及粒子物理规划及未来的中微子实验未来的中微子实验王贻芳王贻芳南昌，南昌，2010 高能物理年会高能物理年会Particle physics: problems and methodsStandard Model: HiggsHigh energy acceleratorsBeyond Standard Model ? SUSY, Extra-dimensions.Compositeness, Neutrino properties: mass, oscillation, magnetic moment ? Majorana ?Cosmology related problems:

2、antimatter(CP) ?Dark matter ?Relic-neutrinos,Monopoles ? Axions ? Details of SM (EW & QCD) : precision test, Confinement, Glueballs ? spectroscopy of particlesHigh intensity acceleratorsUnderground experimentsSurface experimentsSpaceexperimentsHigh energy acceleratorsHigh intensity acceleratorsU

3、nderground experimentsSurface experimentsSpaceexperimentsTevetran:D0CDFLHCATLASCMSILCFlavor phys.:BELLE(II) - bDAFNE sLHCbPANDA High den. phys:ALICEJ-PARCn n osc.:T2KMinosProject-Xn n osc. : SuperK KamLANDbb bb decay: EXO Cuore GerdaDark matter: Xmass Xenon COUPPn AstronomyMonopoleProton decayCosmic

4、-raysHESSMAGICAUGERCTAn mass Katrinn n mag. Mom. TEXONOGrav. WaveRelic n nAxions, Anti-matter/ dark matter: PAMELAFERMIAMSATICAsrtophysics: IntegralHubbleWMAPPlanckParticipate:ATLAS, CMSFlavor phys.:BESIII - cn n osc. :Daya BayCosmic-rays Yang-Ba-JinAsrtophysics:HXMTExperiments in the world and at h

5、ome高能物理未来发展的基本思路高能物理未来发展的基本思路 High energy accelerators 积极参加国际合作积极参加国际合作 High intensity accelerators 充分利用充分利用BESIII，取得国际一流的成果，取得国际一流的成果 寻机建造下一代加速器寻机建造下一代加速器 Underground experiments 充分利用大亚湾，取得国际一流的成果充分利用大亚湾，取得国际一流的成果 准备建造下一代中微子实验准备建造下一代中微子实验 寻机建造新的实验：暗物质、寻机建造新的实验：暗物质、bb bb decay、质子衰变、。、质子衰变、。 Surface

6、experiments 充分利用充分利用ASg g & ARGO，取得国际一流的成果，取得国际一流的成果 积极准备建设积极准备建设LHAASO Space experiments 尽快完成尽快完成HXMT，取得国际一流的成果，取得国际一流的成果 寻机建造新的实验：宇宙线、天体物理、暗物质、。寻机建造新的实验：宇宙线、天体物理、暗物质、。时间安排时间安排 十二五十二五 前期建设的丰收期前期建设的丰收期 取得重大国际影响的成果取得重大国际影响的成果 基础能力建设基础能力建设 达到国际先进水平达到国际先进水平 未来项目的准备与预研未来项目的准备与预研 具有具有国际竞争力国际竞争力 十三五十三

7、五 ：重要的建设项目：重要的建设项目 下一代中微子实验：大亚湾二期下一代中微子实验：大亚湾二期 地下实验：暗物质、地下实验：暗物质、bb bb decay、质子衰变、。、质子衰变、。 空间实验：宇宙线、天体物理、暗物质、。空间实验：宇宙线、天体物理、暗物质、。 十四五：重大建设项目十四五：重大建设项目 下一代加速器下一代加速器5每个新项目必须回答以下问题：每个新项目必须回答以下问题：1）为什么（与其它可能的项目比较：科学目标、经费。）为什么（与其它可能的项目比较：科学目标、经费。）2）怎么做（概念设计、国际竞争力、科学意义、经费、技术、进度、风）怎么做（概念设计、国际竞争力、科学意义、经费、技

8、术、进度、风 险。）险。）3）R&D（问题、技术、方案（问题、技术、方案、计划。）、计划。）Neutrino oscillations: What we know and what we dont know A mixing matrix: Atmospheric Solar Majorana phase CP phase & q q13 Unknowns in neutrino oscillation: q q13 , mass hierarchy, CP phase d d + Majorana phase 下一代中微子实验：大亚湾二期下一代中微子实验：大亚湾二期 中微子振

9、荡：中微子研究的中心中微子振荡：中微子研究的中心 中微子振荡三个未解决的问题：中微子振荡三个未解决的问题：寻找第三种振荡，用寻找第三种振荡，用q q13表示表示 大亚湾中微子实验大亚湾中微子实验质量顺序问题质量顺序问题 大亚湾中微子实验二期大亚湾中微子实验二期 CP对称破缺角对称破缺角 未来的加速器实验未来的加速器实验 n n1n n2n n3q q12太阳中微子振荡太阳中微子振荡q q23大气中微子振荡大气中微子振荡q q13 ?mi ?为什么反应堆中微子：为什么反应堆中微子：1）加速器中微子实验：造价昂贵）加速器中微子实验：造价昂贵 （探测器（探测器+加速器）加速器） 2）双）双实验：造价

10、昂贵，技术困难，风险巨大实验：造价昂贵，技术困难，风险巨大3）中微子绝对质量测量：造价昂贵，技术困难）中微子绝对质量测量：造价昂贵，技术困难4）反应堆中微子实验：意义重大、风险小、条件优越、造价低、技术可行）反应堆中微子实验：意义重大、风险小、条件优越、造价低、技术可行l测量磁矩：可能的未来，科学风险大测量磁矩：可能的未来，科学风险大l精确测量混合参数：大亚湾、大亚湾二期精确测量混合参数：大亚湾、大亚湾二期Best neutrino source: reactor A powerful man-made source If not too far, more powerful than sol

11、ar, atmospheric, and accelerator neutrinos A well understood source（2% 0.1%） Better than solar(5-10%), atmospheric(10%), and accelerator(5-10% 2-3% ?) neutrinos Adjustable baseline Of course, accelerator can do it also A free neutrino factoryNeutrino Mass hierarchy Mass Hierarchy: Fundamental to the

12、 Standard Model Fundamental to models beyond SM Most GUTs predict a normal mass hierarchy a discriminator of different GUTs and/or neutrino mass models Fundamental to many issues: Matter-antimatter asymmetry via leptogenesis in specific seesaw models: hierarchy related Supernova neutrinos: collectiv

13、e flavor transitions due to inverted mass hierarchy Radiative corrections to mn n and q qij are more sensitive to the inverted hierarchyBut even more important Dirac or Majorana ? Neutrino oscillation: beyond SM in a way of Dirac or Majorana mode ? bb bb exp. may never give positive results If mass

14、hierarchy is known, together with next generation bb bb exp., the neutrino Dirac or Majorana nature can be determined. next gen. bb bb exp.Measuring mass hierarchy Long baseline accelerator neutrinos Through Matter effects Expensive, project-X/LBNE in Fermilab/BNL Atmospheric neutrinos Very weak sig

15、nal Huge detector, Expensive Reactor neutrinos Method: distortion of energy spectrum Enhance signature: Transform reactor neutrino L/E spectrum to frequency regime using Fourier formalism need Sin2(2q q13) 0.02 Need to know D DM223 S.T. Petcov et al., PLB533(2002)94S.Choubey et al., PRD68(2003)11300

16、6J. Learned, PRD 78(2008)071302 12Fourier transformation of L/E spectrum Frequency regime is in fact the D DM2 regime enhance the visible features in D DM2 regime Take D DM2 32 as reference NH: D DM2 31 D DM2 32 , D DM2 31 peak at the right of D DM2 32 IH: D DM2 31 0 and PV0 IH: RL0 and PV 90% CL: B

17、aseline: 58 km, determined by q q12 Reactor power 24 GWth Flux and detector size: (250-700) kt year Ideally, sin22q q13 0.02 & energy resolution 2% IF sin22q q13=0.01, energy resolution 2% & 700 kt year For sin22q q13=0.02 , energy resolution 1000 MWE 60 km from Daya Bay A huge n ne detector

18、 with mass 20kt currently the largest on is 1kt (KamLAND & LVD) Scientific goal: a l0-50kt underground LS detector 60km from reactor 1. Neutrino Mass hierarchy2. Precision mixing para. measurement: q q12, D D M212, D DM231 Unitarity of the mixing matrix3. Supernova neutrinos =better than SuperK4

19、. Geo-neutrinos = 10 better than KamLAND5. Atmospheric neutrinos = SuperK6. Solar neutrinos ? 7. High energy neutrinos1.Point source: GRB, AGN, BH, 2.Diffused neutrinos8. High energy cosmic-muons1.Point source: GRB, AGN, BH, 2.Dark matter9. Exotics 1.Sterile neutrinos2.Monopoles, Fractional charged

20、particles, .LVD+MACRO+KamLAND+SuperKPrecision measurement of mixing parameter Fundamental to the Standard Model and beyond Similarities point to a Grand unification of leptons and quarks Constrain all PMNS matrix elements to 1% ! Probing Unitarity of UPMNS to 1% level !If we can spend (0.1-0.5)B$ fo

21、r each B/C/superB factories to understand UCKM ( 1-2 elements for each factory), why not a super-reactor neutrino experiment( 3 elements) to understand UPMNS ? Current BESIII Vub25%5%Vcd7%1%Vcs16%1%Vcb5%3%Vtd36%5%Vts39%5%Current Daya Bay II D Dm2125% 1% D Dm22312% 1%sin2q q1210% 1%Sin2q q2320%-sin2q

22、 q13 -Supernova neutrinos Less than 20 events observed so far (2001 Noble prize) Assumptions: Distance: 10 kpc (our Galaxy center) Energy: 3 1053 erg Ln n the same for all types Tem. & energyMany types of events:n ne + p n + e+, 3000 correlated eventsn ne + 12C 13B* + e+, 10-100 correlated event

23、sn ne + 12C 11N* + e-, 10-100 correlated eventsn nx + 12C n n+ 12C*, 600 correlated eventsn nx + p n n+ p, single eventsn ne + e- n ne + e-, single eventsn nx + e- n n+ e-, single eventsT(n ne) = 3.5 MeV, = 11 MeVT(n ne) = 5 MeV, = 16 MeVT(n nx) = 8 MeV, = 25 MeV SuperK can not see these correlated

24、eventsWhat to do with Supernova neutrinos Energy spectra & fluxes of all types of neutrinos tem. and average energy of neutrinos Understand Supernovae neutrino properties: mass, mixing, Earth tomography Neutrino models Arrival time of all types of neutrinos absolute neutrino massGeo-neutrinos 23

25、8U, 232Th and 40K decays account for 40% of earths power, which is related to earthquakes, volcanoes, geomagnetism, plate tectonics, They are mainly from mantle and crust, but not the core South-china and Japan are different Geo-neutrinos can tell 238U: 232Th good for geo-models Only way looking ins

26、ide the earth ?Already seen by KamLANDGeo-neutrinos at Daya Bay II A factor of 10 larger than KamLAND3 years KamLAND探测器的概念设计探测器的概念设计 Neutrino target: 20kt LS, LAB based 30m(D) 30m(H) Oil buffer: 6kt Water buffer: 10kt PMT: 15000 20” Cost: 1.5 B RMB可能的地点：惠州或海上可能的地点：惠州或海上据大亚湾据大亚湾/海丰海丰60公里公里热功率热功率 40 G

27、WTechnical challenges Requirements: Large detector: 10 kt LS Energy resolution: 2%/ E 2500 p.e./MeV Ongoing R&D: Low cost, high QE “PMT” A new design exist, patent pending, R&D contract to be signed with manufacture transparent LS: 15m 25m Find out traces which absorb light, remove it from production R&D program: 3 yearsUseful for many future projectsSupport already from IHEPNow: 1kt250 p.e./MeV基于基于LAB的液体闪烁体研究的液体闪烁体研究 测量测量LAB成分：成分：4.5% 杂质杂质 利用量子化学的计算，估计、寻找吸收可见光的杂质利用量子化学的计算，估计、寻找吸收可见光的杂质 初步测量杂质在初步测量杂质在L