Which Milky Way masses are consistent with the slightly declining 5–25 kpc rotation curve?

نویسندگان

چکیده

Discoveries of extended rotation curves have suggested the presence dark matter in spiral galaxy haloes. It has led to many studies that estimated total mass, mostly by using Navarro Frenk and White (NFW) density profile. We aim at verifying how choice dark-matter profile may affect predicted values extrapolated masses. considered recent Milky Way (MW) curve, firstly because its unprecedented accuracy, secondly Galactic disk is amongst least affected past major mergers having fully reshaped initial disk. find use NFW (or generalized form, gNFW) for calculating contribution MW curve generates apparently inconsistent results, e.g., an increase baryonic mass leads mass. Furthermore we gNFW narrow range, leading a possible methodological bias particularly against small By Einasto more appropriate represent cold haloes, finally slightly decreasing favors can be as 2.6 $\times 10^{11}$ $M_{\odot}$, disregarding any other dynamical tracers further out MW. with larger than 18 $M_{\odot}$ kind CDM halo profiles, under assumption stars gas do not influence distribution This paper encourages characterizing evaluating their

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ژورنال

عنوان ژورنال: Astronomy and Astrophysics

سال: 2021

ISSN: ['0004-6361', '1432-0746']

DOI: https://doi.org/10.1051/0004-6361/202141058