Maximum Reduced Proper Motion Method: Detection of New Nearby Ultracool Dwarfs

TL;DR

This paper applies the Maximum Reduced Proper Motion method to identify 57 nearby ultracool dwarfs, including 36 new discoveries, using color criteria and proper motion data from multiple sky surveys.

Contribution

It demonstrates the effectiveness of the Maximum Reduced Proper Motion method in discovering new ultracool dwarfs and provides proper motion measurements from archival data.

Findings

Identified 57 nearby ultracool dwarfs, 36 of which are new discoveries.

Measured proper motions using multi-epoch archival images.

Validated the method's utility for nearby ultracool dwarf detection.

Abstract

In this paper, we describe how to use the Maximum Reduced Proper Motion method (Phan-Bao et al. 2003) to detect 57 nearby L and late-M dwarfs (d_phot <= 30 pc): 36 of them are newly discovered. Spectroscopic observations of 43 of the 57 ultracool dwarfs were previously reported in Martin et al. (2010). These ultracool dwarfs were identified by color criteria in ~5,000 square degrees of the DENIS database and then further selected by the method for spectroscopic follow-up to determine their spectral types and spectroscopic distances. We also report here our newly measured proper motions of these ultracool dwarfs from multi-epoch images found in public archives (ALADIN, DSS, 2MASS, DENIS), with at least three distinct epochs and time baselines of 2 to 46 years.