ALMA Band 8 version2 receiver upgrade project

We have initiated an upgrade project for the existing Atacama Large Millimeter/submillimeter Array (ALMA) Band 8 (radio frequency: 385-500 GHz) receiver cartridge with a substantially improved second-generation version, referred to here as ``Band 8v''. This project is originated from significant advances in receiver technologies in the last decade, such as high critical current density superconductor-insulator-superconductor (SIS) mixers, wideband cryogenic low-noise amplifier, and high-performance waveguide components. These will allow us to realize a fundamentally re-designed receiver to cover a substantially wider intermediate frequency (IF) band with lower and flatter receiver noise temperature. In addition to those goals, lessons learned through the development, operation, and maintenance of the current ALMA Band 8 receiver cartridges will be appropriately addressed through this upgrade. In addition to those goals, lessons learned through the development, operation, and maintenance of the current ALMA Band 8 receiver cartridges will be appropriately addressed through this upgrade.