Pixelated resistive bulk micromegas for tracking systems in high rate environment

One of the main objectives within the community of the Micro-Pattern-Gaseous-Detectors (MPGD) is the design of new detectors for operation with a very high particle flow. This research path is driven mainly by future upgrades of existing experiments at high-luminosity LHC or next generation accelerators where gaseous detectors will be operated at rates up to few MHz/cm2, three orders of magnitude higher than nowadays. The goal of our R&D project, started few years ago, is to develop a new generation of single amplification stage resistive MPGD based on Micromegas technology with the following characteristics: stable and efficient operation up to particle fluxes of 10 MHz/cm2; high granularity readout, with pixels of order mm2 and fully integrated electronics; reliable and cost-effective production process. We present here the development status of our small-pads resistive Micromegas prototypes, focusing on the optimization of the spark protection resistive layer. Characterization and performance studies of the prototypes have been carried out by means of radioactive sources, X-Rays and test beams. A comparison of the performance obtained with the different resistive layout realized until now is presented, studying in particular the response under high rate irradiation.