1. Dark Matter: A Mini Review Jin Min Yang 2008.7.23 Hong Kong (杨 金 民)(杨 金 民) Institute of Theoretical Physics Academia Sinica, Beijing

2. Outline Evidence of Dark Matter Candidates of Dark Matter Experiments for Dark Matter SUSY Dark Matter Outlook

3. Galactic clusters: need DM to bind them (1930s, Zwicky) Galaxy rotation curves: need a diffuse halo of DM (1970s, Rubin &Ford) Gravity lensing: strong and weak lensing show DM in universe Hot gas in clusters: need DM to bind the hot gas CMB: CMB power spectrum show composition of universe (WMAP) Large scale structure formation: a universe composed of CDM and DE BBN: light elements abundances agree with observation if n B /n  ~ 6  10 -10 (imply baryon mass density ~ 4  ) Supernovae probe: Hubble diagram indicate DM and DE in universe Colliding clusters: observation of colliding clusters from bullet cluster 1 、 Evidence of Dark Matter

4.    0.3 GeV/cm 3 V  220 km/s

5. What we know about DM so far ? neutral cold (part of it can be warm) weak interaction (with itself and with ordinary matter) profile (around us    0.3GeV/cm 3 V  220 km/s) Identity of DM particle ? candidates

6. 2 、 Candidates of Dark Matter Q-balls: topological solitons in QFT (Coleman, Kusenko) Neutrinos: sterile (Kusenko, 2006) Black hole remnants: tiny BHs produced in early universe Wimpzillas: massive beasts (Kolb et al) Axions: Peccei-Quinn solution to strong CP WIMPs: lightest neutralino in SUSY with R-parity lightest KK excitations in EDT with KK-parity lightest T-odd particle in LHT with T-parity SuperWIMPs: gravitino in SUSY with R-parity axino—fermionic partner of axion lightest KK graviton in EDT

7. Why WIMP is popular and favored ? (1) naturally predicted in new physics models (SUSY, Extra-dimension, LHT) lightest neutralino in SUSY with R-parity lightest KK excitations in extra-dimension lightest T-odd particle in LHT with T-parity (2) naturally give the correct relic density of DM

8. 10 -34 秒 BBN 1 秒1 秒 10 13 秒 10 18 秒 Thermal equilibrium   ff Universe cools: n=n EQ  e -m/T Freeze out ~ 0.1 WIMP correct relic density of DM

9. Note: so far all DM information is from astro observation ! (gravity effects of DM) Nature (identity & property) of DM particle experiments

10. 3 、 Experiments for Dark Matter 3.1 Astrophysical experiments   indirect detection direct detection land-based high altitude space-based 3.2 Collider experiments (LHC, ILC)  p e+e+  _

11. (a) direct detection 3.1 Astrophysical experiments

12. (b) indirect detection (anti-particle)

13. (c) indirect detection (photon) W. de Boer ARGO-YBJ

14. (d) indirect detection (neutrino)

15. 3.2 Collider study of dark matter Tevatron (now) LHC (2008) ILC (???) model-dependent study model-independent study (possible) model-dependent study Birkel,Matchev,Perelstein, 2004   

16. 4. SUSY Dark Matter

17. LSP neutralino (WIMP) gravitino (SuperWIMP)

18. 4.1 Neutralino (WIMP) Dark Matter (a) Allowed parameter space: Baer,Tata (2008)

19. (b) Astrophysical expts: Baer,Tata (2008)

20. (c) Collider expts (LHC, ILC): LHC Baltz et al (2006) Baer,Tata (2008)

21. (d) Collider + Astrophysical expts: Baer,Tata (2008) Baer, et al (2004)

22. (1) Interaction: Suppressed by  E/M * (extremely weak !) 4.2 Gravitino (SuperWIMP) Dark Matter (gaugino & gauge boson) (fermions) (2) Relic density: Weinberg (1982) Cyburt, Ellis, Fields, Olive (2003) Kawasaki, Kohri, Moroi (2005) Feng, Rajaraman, Takayama, Su (2003) (thermal)(late-decay of NLSP)

23. (3) Astrophysical expts: Null results ! (due to extremely weak interaction) (4) Collider expts: Detect NLSP (meta-stable) NLSP (stau) SM particle LHC Hamaguchi, kuno, Nakaya, Nojiri (2004) Feng, Smith (2004)

24. WIMP Property Collider Experiments 5. Outlook

25. WMAP(current) Planck(~2010) LHC (“best case scenario”) ILC LCC1 Battaglia (2005)