Line: 1 to 1  

DefinitionThe coordinate system used for defining the parametrization of tracks is Cartesian and righthanded with its origin located at the interaction point.  
Changed:  
< <  The z axis is given by the detector z axis and the y axis lies along the vertical direction, pointing upwards.  
> >  The z axis is given by the detectors z axis and the y axis lies along the vertical direction, pointing upwards.  
Whenever a charged particle is affected by a constant magnetic field it moves on a helicoidal trajectory, where here and in the following both energy loss  
Changed:  
< <  and multiple scattering are neglected. It is assumed that this magnetic field is homogeneous and parallel to the z axis. In this case the trajectory of a charged particle is a segment of a circle in the xy projection and the z displacement is a linear function of the length s of the arc that is described in the xy plane. This results in a straight line in the sz plane.  
> >  and multiple scattering are neglected. It is assumed that this magnetic field is homogeneous and parallel to the z axis. In this case the trajectory of a charged particle is a segment of a circle in the xy projection and the z displacement is a linear function of the length s of the arc that is described in the xy plane. This results in a straight line in the sz plane.  
Changed:  
< <  The parametrisation of the movement of a charged particle is defined by a reference point, P^{r} = (P^{r}_{x}, P^{r}_{y}, P^{r}_{z }), and five socalled "track parameters" (Ω,Φ_{0},d_{0}, z_{0} and tan λ). In general the reference point can be any point in space but usually it is set to the origin of the coordinate system. The five track parameters refer to a specific point P_{0} = (P0x ; P0y ; P0z ) along the helix, here P0 is defined as the point of closest approach (p.c.a.) to the reference point in the xy plane.  
> >  The parametrisation of the movement of a charged particle is defined by a reference point, P^{r} = (P^{r}_{x} , P^{r}_{y} , P^{r}_{z }), and five socalled "track parameters" (Ω , Φ_{0} , d_{0} , z_{0} and tan λ). In general the reference point can be any point in space but usually it is set to the origin of the coordinate system. In general, the five track parameters refer to a specific point P^{0} = (P^{0}_{x} , P^{0}_{y} , P^{0}_{z} ) along the helix, but here P^{0} is defined as the point of closest approach to the reference point in the xy plane.  
Added:  
> >  The xy Plane  
Changed:  
< < 
 
> >   
Changed:  
< < 
 
> >  
Added:  
> >  In the xy plane the movement of a charged particle is defined by the reference point, P^{r} = (P^{r}_{x} , P^{r}_{y}) and three parameters, Ω, Φ_{0}, d_{0}:
The centre point P^{c} = (P^{c}_{x} , P^{c}_{y}) of the circle in the xy plane is usually different from the reference point P^{r}.
The sz Plane
In the sz plane a charged particle moves along a straight line, which is described by two parameters, tan λ and z_{0}:
 
Simulation and Reconstruction  
Added:  
> >  The impact parameter resolution studies presented here were done for the parameters d_{0} and z_{0} using the software tools MOKKA and Marlin.
Muon gun
Detector Models are summarized here: ImpactParameter Resolution  
Results for SuperBelle and SuperBelle Upgrade 
Line: 1 to 1  

Added:  
> > 
DefinitionThe coordinate system used for defining the parametrization of tracks is Cartesian and righthanded with its origin located at the interaction point. The z axis is given by the detector z axis and the y axis lies along the vertical direction, pointing upwards. Whenever a charged particle is affected by a constant magnetic field it moves on a helicoidal trajectory, where here and in the following both energy loss and multiple scattering are neglected. It is assumed that this magnetic field is homogeneous and parallel to the z axis. In this case the trajectory of a charged particle is a segment of a circle in the xy projection and the z displacement is a linear function of the length s of the arc that is described in the xy plane. This results in a straight line in the sz plane. The parametrisation of the movement of a charged particle is defined by a reference point, P^{r} = (P^{r}_{x}, P^{r}_{y}, P^{r}_{z }), and five socalled "track parameters" (Ω,Φ_{0},d_{0}, z_{0} and tan λ). In general the reference point can be any point in space but usually it is set to the origin of the coordinate system. The five track parameters refer to a specific point P_{0} = (P0x ; P0y ; P0z ) along the helix, here P0 is defined as the point of closest approach (p.c.a.) to the reference point in the xy plane.
Simulation and Reconstruction
Results for SuperBelle and SuperBelle Upgrade
 AndreasMoll  20 Mar 2009
