Quench Margin Measurement in ${\rm Nb}_{3}{\rm Sn}$ Quadrupole Magnet

One of the possible practical applications of the Nb3Sn accelerator magnets is the LHC luminosity upgrade that involves replacing the present NbTi focusing quadrupoles in two high-luminosity interaction regions (IR). The IR magnets are exposed to strong radiation from the interaction point that requires a detailed investigation of the magnet operating margins under the expected radiation-induced heat depositions. This paper presents the results of simulation and measurement of quench limits and temperature margins for a Nb3Sn model magnet using a special midplane strip heater.