First analysis results

First results of the analysis


First measurements with the silicon detector were performed to verify the principle function of the system. The first goal of the tests was to find hits in single modules. After this, a reconstruction of tracks through the modules towards the target wires was done. Therefor, the detector was run with various target configurations to investigate the behavior of the detector under these different circumstances.

Target wires seen by the silicon vertex detector

Clearly visible are distinct clusters of transverse (x,y) coordinates in the plane of the target wires, obtained by linear extrapolation of track candidates measured by two of the double sided silicon wafers. The resolution orthogonal to the wires is around 300u, parallel to the wires the convolution of the intrinsic vertex resolution with the beam profile leads to a width around 600u.

Measurement of longitudinal target position

The sharpness of the the vertex spot in the x and y projections is shown as function of the assumed z-position of the target wires. One plot shows the focus scan for a horizontal, the other one for a vertical wire. In both cases the focus is sharper orthogonal to the wire, only limited by the intrinsic resolution of the measurement. One can also resolve the different z-coordinates of horizontal and vertical wires, which in beam direction are separated by 1cm.

For more details on the actual data analysis, contact Michael Schmelling