Upgrading the beam telescopes at the DESY II Test Beam Facility

The DESY II Test Beam Facility is a key infrastructure for modern high energy physics detector development, providing particles with small momentum spread in range from 1 to 6 GeV user groups e.g. the LHC experiments and Belle as well generic R&D. telescopes are provided all three test beam areas precise tracking reference without time stamping, triggered readout of > 115 $\mu$s. If highest available rates used, multiple traversing within one frame, thus creating ambiguities that cannot be resolved additional timing layers. Several upgrades currently investigated tested: Firstly, fast monolithic pixel sensor, TelePix, provide track triggering on region interest proposed overcome this limitation. TelePix 180 nm HV-CMOS sensor has been developed jointly by DESY, KIT University Heidelberg designed at KIT. In publication, performance evaluation presented: difference between two amplifier designs evaluated. A hit detection efficiency above 99.9 % combined resolution below 4 ns negligible noise determined. Finally, digital output evaluated shows short absolute delay respect traditional trigger scintillator an excellent resolution. Secondly, LGAD plane few 10 ps, which foreseen drastically improve telescope. Time resolutions 70 ps have determined collaboration California, Santa Barbara.