  High-gradient linacs of next generation require novel accelerating structures
which are compact, robust and cost-effective. Dedicated research and
development have been launched in the linear-collider community. This paper
focuses on the technological developments directed to show the viability of
novel welding techniques and related applications, in order to benefit from the
superior high-gradient performance of accelerating structures made of
hard-copper alloys. The structure geometry that we propose allows getting a
high longitudinal shunt impedance of the accelerating mode and increasing the
mode separation frequencies.
