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tokens: when the Chabrier IMF is adopted. However, we argue that a 20% contribution from the thick disk at the local disk is seriously overestimated. Our results suggest that the thick disk contributes only a few percent mass density at the disk midplane, which is consistent with many literature results (e.g., Jurić et al. 2008 ; Chen et al. 2017 ). We emphasize that our results are obtained at solar radius but not the “solar neighborhood.” Our sample stars have a good coverage at 400–800 pc away from the Sun in the azimuthal direction but have poor coverage within 400 pc. A likely explanation of the higher density found by this work than the solar-neighborhood values in the literature is that the Sun is located in a local low stellar density region, which has a density of 0.0164 M ⊙ pc −3 (or 0.0106 M ⊙ pc −3 if the Chabrier IMF adopted) lower than the nearby disk. Such a difference must be contributed by the Local stellar arm. Our Sun is either located at the inner boundary of the Local arm or embedded in a cavity of stars in the arm, and it needs to be further studied using data with improved spatial coverage to clarify which is the real case. Note that the literature results for the solar-neighborhood density are usually determined within a complex volume, which varies with different types of stars. It is thus difficult to make a direct comparison of our relatively well defined volume density with the literature results. To test whether the difference is caused by the possibility that the literature results are actually averaged values in a larger volume, we have also examined the mean stellar mass density within 7.8 kpc R 8.2 kpc and pc, and we find a density of 0.0549 M ⊙ pc −3 (0.0496 M ⊙ pc −3 from the Chabrier IMF), which is still significantly higher than the “solar-neighborhood” values in the literature. We also emphasize that since the stellar mass density decreases quickly with increasing height above the disk plane, the “underlying” midplane density should be higher than the current estimates of average values within pc. The midplane density is expected to be comparable to the measured values without correction for contaminations of main-sequence stars (Section 4 ). Assuming a gas density of 0.05 M ⊙ pc −3 as widely adopted (Holmberg Flynn 2000 ; Flynn et al. 2006 ), the expected mass density of baryon matter (star and gas) in the nearby disk plane within a few hundred parsecs is thus 0.109 M ⊙ pc −3 (0.104 M ⊙ pc −3 for the Chabrier IMF). Such a value is highly consistent with the local total mass density yielded by stellar dynamics, which suggest a typical value of 0.1 M ⊙ pc −3 , with an uncertainty of ∼0.01 M ⊙ pc −3 (Bienayme et al. 1987 ; Kuijken Gilmore 1989c ; Pham 1997 ; Holmberg Flynn 2000 ; Read 2014 ; McKee et al. 2015 ; Widmark Monari 2017 ; Kipper et al. 2018 ). Our results thus leave little room for the existence of a meaningful amount of dark matter in the nearby disk midplane. However, since our results show that