Performance of the electromagnetic pixel calorimeter prototype Epical-2

The first evaluation of an ultra-high granularity digital electromagnetic calorimeter prototype using 1.0-5.8 GeV/c electrons is presented. $25\times10^6$ pixel detector consists 24 layers ALPIDE CMOS MAPS sensors, with a pitch around 30~$\mu$m, and has depth almost 20 radiation lengths tungsten absorber. Ultra-thin cables allow for very compact design. properties that are critical physics studies measured: shower response, energy resolution linearity. stochastic comparable the state-of-the art Si-W calorimeter, data described well by simulation model GEANT Allpix$^2$. performance achieved makes this technology good candidate use in ALICE FoCal upgrade, general demonstrates strong potential future applications high-energy physics.