M. Cobal, PIF 2006/7 Units and kinematics
M. Cobal, PIF 2006/7 Units in particle physics
M. Cobal, PIF 2006/7 Other Units
M. Cobal, PIF 2006/7 QuantityUnits HEUnits SI Lenght1 fm m Energy1 GeV=10 9 eV1.602x J Mass1 GeV/c x Kg h6.59x GeVs1.055x J s c2.998x10 23 fms x10 8 ms -1 hc GeV fm3.162x J m Natural Units = c = 1 Mass 1 GeV Lenght 1 GeV -1 Time 1 GeV -1 1 Volt - + U = 1 eV Units in particle physics
M. Cobal, PIF 2006/7 Co-moving coordinate systems v S S’ x x’’ Example: Muons, s, in cosmic ray p =10 GeV l v 60 km (not. 600 m) Lorentz contraction: length reduction with motion Time dilatation: Lenght at rest Time at rest Lorentz transformation
M. Cobal, PIF 2006/7 Relativistic kinematics
M. Cobal, PIF 2006/7 4-vector Invariant for rotations : Introducing the metric : Lorentz-invariant in terms of scalar, 4-vectors Contro-variant 4-vec Co-variant 4-vec Notation
M. Cobal, PIF 2006/7 Four vectors
M. Cobal, PIF 2006/7 Four vectors addition
M. Cobal, PIF 2006/7 Kinematics example
M. Cobal, PIF 2006/7
Observables
M. Cobal, PIF 2006/7
mAmA mBmB mCmC c.m. frame Example EE EeEe 2-Body Decay
M. Cobal, PIF 2006/7
Decay Width