地下暗物质粒子 ( 直接 ) 探测研究 高能物理研究所 吕军光
DESCRIPTION
地下暗物质粒子 ( 直接 ) 探测研究 高能物理研究所 吕军光. 1 . 直接探测暗物质粒子背景 2. 利用惰性液体探测方法 3. 利用闪烁晶体探测方法. 暗物质的存在证据. 星系旋转曲线. 大尺度结构. 微波背景辐射. 暗物质基本特点: 宇宙学时间尺度上稳定。 参与引力作用,电中性。 非重子物质 非相对论性运动 Local mass density of DM near Solar System ~0.3 Ge V /cm3 Velocity of DM particles in Milky Way: ~ 220 km/s. 强引力透镜. - PowerPoint PPT PresentationTRANSCRIPT
-
()
1.2.3.
-
Local mass density of DM near Solar System ~0.3 GeV /cm3Velocity of DM particles in Milky Way: ~ 220 km/s
-
Galaxy configurationDark matter halo*
-
WIMPRecoiled nucleusDirect detection of galactic dark matterEvent rate < 1/kg/dayWIMP densityD=0.3 GeV/c2/cm3
-
(SI) WIMPLArLXeCsI30/1.5/1
-
Experimen Target Type Status Site NationANAIS NaI annual modulationconstruction Canfranc SpainDAMA/NaI NaI annual modulationconcluded LNGS INFN-ITALYDAMA/LIBRA NaI annual modulation running LNGS INFN-ITALYDAMA/1 ton NaI annual modulation R&D LNGS INFN-ITALYNAIAD NaI PSD concluded Boulby UKHDMS Ge ionization concluded LNGS INFN-ITALYKIMS CsI PSD R&D Y2L KoreaCaf2-Kamioka CaF2 PSD running Kamioka JapanDAMA/LXe LXe PSD running LNGS INFN-ITALYWARP LAr 2 phase running LNGS INFN-ITALYXENON 10 LXe 2 phase running LNGS INFN-ITALYZeplin II LXe 2 phase running Boulby UKZeplin III LXe 2 phase installation Boulby UKArDM LAr 2 phase R&D Canfranc SpainLUX LXe 2 phase R&D Dusel USACLEAN LNe PSD R&D USADEAP LAr PSD R&D SNOLAB(CANADA) USA XMASS LXe PSD construction Kamioka JapanCDMS Ge bolometer running Soudan USACRESST CaWO4 bolometer running LNGS INFN-ITALY-ItalyEDELWEISS Ge bolometer running Frejus FranceROSEBUD Ge, sap,tung bolometer R&D Canfranc SpainCOUPP F SH droplet R&D Fermilab USA PICASSO F SH droplet running+R&D SNOLAB CANADASIMPLE F SH droplet running+R&D Bas Bruit FranceDrift CS2 gas TPC R&D Boulby UKMIMAC 3He gas TPC R&D
-
Double-Phase Noble Liquids LXe detects prompt (S1) light signalafter a particle interacts in the active xenon drifts the charge, extracts into the gas phase and detects as proportional light (S2)
-
Double-Phase Noble Liquids LXeXENON10
-
Recent results of a liquid noble gas experiment: XENON10Experimental site:Gran Sasso (1400 m depth)Target material:natXeTarget mass:5.4 kg (tot: 15 kg)Used exposure:136 kg day
-
Double-Phase Noble Liquids LXe(Double-Phase,~3
-
Double-Phase Noble Liquids LArArDM
-
Double-Phase Noble Liquids LArTime ns
tagged ( 22Na) Neutron (AmBe)Fprompt=Q(
-
LArLXeScintillationand Ionization read outliquid ArVolume for shieldingFiducial volumeTHGEM+ LM Fiducial VolumeLArLArLArLArLAr77 K87 K
-
Double-Phase Noble Liquids LAr(Double-PhaseDouble-PhaseD-P
-
(Noble Liquids)():1, :PMT() :
2,(CsIGaN)GEM(CsI )+() :
-
Electron avalanche in LAr+LXe at the tip of needle
-
Electron avalanche in LAr+LXe at the tip of needle
-
(Noble Liquids) ():1, 1) 2) APD 3) (LAr)
2,(CsIGaN) GEM()+
- (CsI(Na)):1,(PMT) Noble Liquids 3D,:(2Cm),(
-
2.5x2.5x2.5cm ESR
-
n Gamma (200ns/)
-
14MeV
-
14MeV1, 2 CHAN: CsI(Na)1 CHAN: CsI(Na)2 CHAN:
-
n/ Quenching factor
-
(Pu239)/(Am241)
-
5kev-Ee():0.2ns/chan
-
1kev-Ee():0.2ns/chan
-
0.5-6kev
-
cut
-
(Pu239)/(Am241)
-
3D--MC200x200x200 mm PMT50mm, 96PMT : 12 p.e./KeV(25,25,4.9)mm sigma/z : 0.75mm(25,25,93.1)mm sigma/z: 1.2mm
-
CsICsI()CsI2
-
CsI(Na):1.: CsI(/) +NaI(0.01%)(/) ?2.()3.
: PMTCsI(Na)(~16%
-
Internal background137Cs : t 1/2= 30.07 year (Artificial) b decay to 137Ba* (Q = 1175.6 keV) 2 min life time, emitting 661.6 keV gamma Hard to reject134Cs : t 1/2 = 2.065 year : Artificial+ 133Cs(n,) b to 134Ba* (Q=2058.7 keV) prompt emission Can be rejected easily : not a problemRadioisotopes in the crystal87Rb : t 1/2 = 4.75 x 1010 year (27.8% nat. abun.) b Beta deacy to 87Sr (Q=282.3 keV) no emission Hard to reject reduction technique in material is known1.07 cpd/ppb0.35 cpd/mBq/kg @ 10 keV0.07 cpd/mBq0.005 cpd/mBq137Cs : 10 mBq/kg134Cs : 20 mBq/kg87Rb : 10 ppbGeant Simulation
-
Quenching factors, q, measured by neutron sources or by neutron beams for some detectors and nucleidifferences are often present in different experimental determinations of q for the same nuclei in the same kind of detectore.g. in doped scintillators q depends on dopant and on the impurities/trace contaminants; in LXe e.g.on trace impurities, on initial UHV, on presence of degassing/releasing materials in the Xe, on thermodynamical conditions, on possibly applied electric field, etc.Some time increases at low energy in scintillators (dL/dx) and more
recoil/electron response ratio measured with a neutron source or at a neutron generatorEx. of different q determinations for GeQuenching factor
-
**