The SDSS-V Local Volume Mapper (LVM): Technical Overview

Abstract

The Sloan Digital Sky Survey V (SDSS-V) Local Volume Mapper (LVM) is an ultra-wide integral field spectroscopic survey of the Milky Way, the Magellanic Clouds, and a sample of galaxies in the local volume. The LVM spatially resolved spectroscopy covers the bulk of the optical range (3600-9800 A) at medium spectral-resolution (R = 2200-5500), and maps the disks of these galaxies at high physical spatial resolution (< 1 pc in the MW and ~10 pc in the Magellanic Clouds). Observations are carried out with the LVM Instrument (LVM-I), a custom-built robotic telescope, instrument, and facility located at Las Campanas Observatory (LCO) in Chile. In this article we present a technical overview of the LVM project. We describe the hardware, the survey observing strategy, and the details of how science and calibration observations are carried out. We provide a high-level overview of the survey data flow, including the reduction and calibration of the LVM spectra, and the production of the main data products that are released by the project. We also present an assessment of the LVM data quality and instrumental stability based on science observations. The main goal of this article is to serve as a primer for LVM users, providing the technical information required for the adequate analysis, modeling, and interpretation of the LVM data.