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تسجيل مستخدم جديدThe universal rotation curve of low surface brightness galaxies IV: the interrelation between dark and luminous matter
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We investigate the properties of the baryonic and the dark matter components in low surface brightness (LSB) disc galaxies, with central surface brightness in the B band $mu_0 geq 23 , mag , arcsec^{-2}$. The sample is composed by 72 objects, whose rotation curves show an orderly trend reflecting the idea of a universal rotation curve (URC) similar to that found in the local high surface brightness (HSB) spirals in previous works. This curve relies on the mass modelling of the coadded rotation curves, involving the contribution from an exponential stellar disc and a Burkert cored dark matter halo. We find that the dark matter is dominant especially within the smallest and less luminous LSB galaxies. Dark matter halos have a central surface density $Sigma _0 sim 100 , M_{odot} pc^{-2}$, similar to galaxies of different Hubble types and luminosities. We find various scaling relations among the LSBs structural properties which turn out to be similar but not identical to what has been found in HSB spirals. In addition, the investigation of these objects calls for the introduction of a new luminous parameter, the stellar compactness $C_*$ (analogously to a recent work by Karukes & Salucci), alongside with the optical radius and the optical velocity in order to reproduce the URC. Furthermore, a mysterious entanglement between the properties of the luminous and the dark matter emerges.
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Dark matter (DM) is one of the biggest mystery in the Universe. In this review, after a brief discussion of the DM evidences and the main proposed candidates and scenarios for the DM phenomenon, we focus on recent results on rotating disc galaxies gi
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Recent advancements in the imaging of low-surface-brightness objects revealed numerous ultra-diffuse galaxies in the local Universe. These peculiar objects are unusually extended and faint: their effective radii are comparable to the Milky Way, but t
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