ATLAS Trigger and DAQ upgrades for High-Luminosity LHC

The ATLAS Trigger-DAQ system will be significantly upgraded to explore new physics beyond the standard model in the High-Luminosity LHC environment with instantaneous luminosity of up to $7.5 \times 10^{34}$ cm$^{-2}$s$^{-1}$. Two general trigger schemes are under study and their prospects and concerns are discussed. The muon trigger and readout electronics will be totally replaced to cope with a longer latency and a higher trigger rate. At the same time, new trigger algorithms using the precision tracker will be introduced to sharpen efficiency turn-ons and suppress fake triggers. The algorithm and the expected performance of the muon trigger are described. The hardware based track trigger is one of the major items introduced in the upgrade program. It will improve the trigger performance of various trigger items with a combination of the calorimeter or muon signature. The procedure for processing track information and an expected performance on the electron trigger are presented.