Extreme Multiplex Spectrograph: An efficient mechanical design for high-demanding requirements

TL;DR

The paper presents an innovative mechanical design for the Extreme Multiplex Spectrograph (XMS) that optimizes space, alignment, and thermal stability for high-demanding astronomical observations.

Contribution

It introduces a novel mechanical design approach for XMS that addresses space constraints, alignment precision, and thermal self-centering in a complex multi-channel spectrograph.

Findings

Design achieves minimal channel separation for high filling factor

Ensures tight alignment tolerances under space and mass constraints

Provides effective lens self-centering during temperature variations

Abstract

XMS is a multi-channel wide-field spectrograph designed for the prime focus of the 3.5m Calar-Alto telescope. The instrument is composed by four quadrants, each of which contains a spectrograph channel. An innovative mechanical design -at concept/preliminary stage- has been implemented to: 1) Minimize the separation between the channels to achieve maximal filling factor; 2) Cope with the very constraining space and mass overall requirements; 3) Achieve very tight alignment tolerances; 4) Provide lens self-centering under large temperature excursions; 5) Provide masks including 4000 slits (edges thinner than 100\mu). An overview of this extremely challenging mechanical design is here presented.