TheDarkMatterProblemastrophysicalprobeofparticlenatureofDM毕效军中国科学院高能物理所2009/12/16
The Dark Matter Problem astrophysical probe of particle nature of DM 毕效军 中国科学院高能物理所 2009/12/16
OutlineWhatwehavelearnedfromastrophysicsevidenceof DMand itsabundanceDMis not baryonicDMis not hot'problems" of LCDM modelcuspyhalosand missingsatellitesalternativemodelsofDMastrophysicalanswersWhat we learned fromparticle physicsWIMP:theclassicCDMdirectdetectionindirect detection:excesses ofelectrons andpositronsnon-standardCDM
Outline What we have learned from astrophysics evidence of DM and its abundance DM is not baryonic DM is not hot “problems” of LCDM model cuspy halos and missing satellites alternative models of DM astrophysical answers What we learned from particle physics WIMP: the classic CDM direct detection indirect detection: excesses of electrons and positrons non-standard CDM
Evidencesgalaxy scaleGM(r)for rFromtheKepler'slaw,Vciremuch larger than the luminous terms, you shouldhave vor-1/2 However, it is flat or rises slightlyv (km/s)observedThe most directevidence of the100existence of darkexpectedfrommatter.50luminous disk10R (kpc)Corbelli&Salucci(2000)：Bergstrom (2000)M33rotationcurve
Evidences — galaxy scale ◼ From the Kepler’s law, for r much larger than the luminous terms, you should have v∝r -1/2 However, it is flat or rises slightly. r GM r vcirc ( ) = ◼ The most direct evidence of the existence of dark matter. Corbelli & Salucci (2000); Bergstrom (2000)
dynamics of galaxy clusterVirial theoremComaclusterU=2KK = Zm; v2U ~ GM2/Rmass to light ratio (B)typical cluster: 100/h-300/h Ysunstellar pop: 1-10 Ysuncritical: 1390 h +-35%RADIUS(MIN)
dynamics of galaxy cluster Virial theorem U=2K K = mi vi 2 U ~ GM2 /R mass to light ratio (B) typical cluster: 100/h-300/h Sun stellar pop: 1-10 Sun critical: 1390 h +- 35% Coma cluster
X-ray clusterhydrostaticequilibriumdlogTGM(T)kBTdlogp一72drdrumnbeta model:p = p(0)(1 + r2 /r2)-3β/2However,X-rayemissionmeasuresthetemperatureandM/Mvisible=20
X-ray cluster hydrostatic equilibrium beta model: However, X-ray emission measures the temperature and M/Mvisible=20