CERN Accelerating science

Measurement of MIMOSA28 charged particle detection efficiency (bullets) and fake hit rate (crosses) as a function of the threshold values (in mV) of the discriminators implemented in the sensor before (solid lines) and after irradiation (dashed lines).

noimgComparison of the requirements of various vertex detectors, in terms of read-out speed ($\sigma_{t}$) and radiation tolerance related to the total ionising dose (TID) and non-ionising particle fluence.

Charges collected from $^{55}Fe$ X-rays illumination of a MIMOSA32 pixel including PMOS transistors. Left: seed pixel alone. Right: $2\times2$ cluster. Solid empty histogram: before irradiation, Dotted filled histogram: after a 3~MRad TID.

MIMOSA32 $20\times40$~$\mu$m$^{2}$ elongated pixel beam test results (60-120~GeV $\pi$): SNR distribution for four temperature-radiation load conditions.

MIMOSA32 test beam results: evolution of the detection efficiency with the temperature and radiation load conditions, for three pixel variants.

Expected performances of a square pixel ($20\times20$~$\mu$m$^{2}$) integrating a preamplification, with emulated binary output from test beam results. The detection efficiency (black bullets), the fake rate (blue squares) and the spatial resolution (red triangles) evolutions with the discriminator threshold (in units of noise) are displayed for three different radiation loads and at the highest coolant temperature of 30$^{\circ}$C.