1. The Estimated Limits For A 5g LE-Ge Detector
Q. Yue
Tsinghua Univ.

2. matter  0.3  baryon  0.01-0.03  lum  0.003 
Components of the Universe:
matter  0.3 
baryon  
lum  
It shows: DM is the dominant component of the universe.
Main part of it is Non-baryonic DM.

3. ...... Massive neutrinos WIMP (Weekly Interactive Massive Particles )
Neutralino
(Lightest super-symmetric particle)
Axion
......

4. Direct Detection of WIMPs

5. The basic conditions of WIMP detector :
High detection efficiency
High pure target material
Good shielding
Good PSD capability
Low threshold

6. Principles of direct detection:
ER : the recoil energy
E0 : the most probable incident energy of a dark matter particle of
mass MD
r : a kinematical factor
R : the event rate ( 1/KeV · Day · Kg )
R0 : the total event rate ( 1/Day · Kg )

7. The possible mass range of WIMPs:
1 — 1000 GeV c-2
Typical recoil energies are in the range keV.
So good shielding is necessary to eliminate nuclear recoils from neutrons produced by cosmic ray muons.
Methods of discriminating between nuclear recoils and electrons

8. The right-hand side is considerably complicated owing to the following corrections.
a Detector on the Earth, in orbit around sun, and solar system moving
through the Galaxy.
b The Quenching Factor.
c The target may consist of more than one elements.
d Instrumental resolution and threshold effects.
e SD & SI
f Form factor

9. Take account all of these factors:
vmax = vescape
= 650km/s

11. DAMA results:

12. Our estimated results:
Target mass: 5g
QF: 0.25
Counts rate: 0.1 /keV·kg·day
Threshold: 100KeV