Abstract We present the discovery of a low-mass comoving system found by means of the NOIRLab Source Catalog DR2. The system consists of the high proper-motion star LEHPM 5005 and an ultracool companion 2MASS J22410186-4500298 with an estimated spectral type of L2. The primary (LEHPM 5005) is likely a mid-M dwarf but over-luminous for its color, indicating a possible close equal mass binary. According to the Gaia EDR3 parallax of the primary, the system is located at a distance of 58 ± 2 pc. We calculated an angular separation of 7.″2 between both components, resulting in a projected physical separation of 418 au.
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Discovery of 34 Low-mass Comoving Systems Using NOIRLab Source Catalog DR2
We present the discovery of 34 comoving systems containing an ultracool dwarf found by means of the NOIRLab Source Catalog (NSC) DR2. NSC’s angular resolution of ∼ 1″ allows for the detection of small separation binaries with significant proper motions. We used the catalog’s accurate proper motion measurements to identify the companions by cross-matching a previously compiled list of brown dwarf candidates with NSC DR2. The comoving pairs consist of either a very low-mass star and an ultracool companion, or a white dwarf and an ultracool companion. The estimated spectral types of the primaries are in the K and M dwarf regimes, those of the secondaries in the M, L, and T dwarf regimes. We calculated angular separations between ∼2″ and ∼ 56″, parallactic distances between ∼43 and ∼261 pc, and projected physical separations between ∼169 and ∼8487 au. The lowest measured total proper motion is 97 mas yr−1, with the highest 314 mas yr−1. Tangential velocities range from ∼23 to ∼187 km s−1. We also determined comoving probabilities, estimated mass ratios, and calculated binding energies for each system. We found no indication of possible binarity for any component of the 34 systems in the published literature. The discovered systems can contribute to the further study of the formation and evolution of low-mass systems as well as to the characterization of cool substellar objects.
more » « less- NSF-PAR ID:
- 10485050
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 164
- Issue:
- 1
- ISSN:
- 0004-6256
- Format(s):
- Medium: X Size: Article No. 3
- Size(s):
- ["Article No. 3"]
- Sponsoring Org:
- National Science Foundation
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