The MiMeS Survey of Magnetism in Massive Stars: Introduction and overview

TL;DR

The MiMeS survey is the largest systematic spectropolarimetric study of magnetic fields in massive O and B stars, aiming to understand their magnetic properties and their impact on stellar evolution.

Contribution

This paper introduces the MiMeS survey, detailing its scope, methodology, instrumentation, and initial results, marking the first comprehensive investigation of magnetism in massive stars.

Findings

Collected over 4800 spectra of 560 stars

Achieved sensitivity to surface dipole fields above 100 G

Established a large dataset for future magnetic studies

Abstract

The MiMeS project is a large-scale, high resolution, sensitive spectropolarimetric investigation of the magnetic properties of O and early B type stars. Initiated in 2008 and completed in 2013, the project was supported by 3 Large Program allocations, as well as various programs initiated by independent PIs and archival resources. Ultimately, over 4800 circularly polarized spectra of 560 O and B stars were collected with the instruments ESPaDOnS at the Canada-France-Hawaii Telescope, Narval at the T\'elescope Bernard Lyot, and HARPSpol at the European Southern Observatory La Silla 3.6m telescope, making MiMeS by far the largest systematic investigation of massive star magnetism ever undertaken. In this paper, the first in a series reporting the general results of the survey, we introduce the scientific motivation and goals, describe the sample of targets, review the instrumentation and observational techniques used, explain the exposure time calculation designed to provide sensitivity to surface dipole fields above approximately 100 G, discuss the polarimetric performance, stability and uncertainty of the instrumentation, and summarize the previous and forthcoming publications.