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We introduce SPARC (Spitzer Photometry & Accurate Rotation Curves): a sample of 175 nearby galaxies with new surface photometry at 3.6 um and high-quality rotation curves from previous HI/Halpha studies. SPARC spans a broad range of morphologies (S0 to Irr), luminosities (~5 dex), and surface brightnesses (~4 dex). We derive [3.6] surface photometry and study structural relations of stellar and gas disks. We find that both the stellar mass-HI mass relation and the stellar radius-HI radius relation have significant intrinsic scatter, while the HI mass-radius relation is extremely tight. We build detailed mass models and quantify the ratio of baryonic-to-observed velocity (Vbar/Vobs) for different characteristic radii and values of the stellar mass-to-light ratio (M/L) at [3.6]. Assuming M/L=0.5 Msun/Lsun (as suggested by stellar population models) we find that (i) the gas fraction linearly correlates with total luminosity, (ii) the transition from star-dominated to gas-dominated galaxies roughly corresponds to the transition from spiral galaxies to dwarf irregulars in line with density wave theory; and (iii) Vbar/Vobs varies with luminosity and surface brightness: high-mass, high-surface-brightness galaxies are nearly maximal, while low-mass, low-surface-brightness galaxies are submaximal. These basic properties are lost for low values of M/L=0.2 Msun/Lsun as suggested by the DiskMass survey. The mean maximum-disk limit in bright galaxies is M/L=0.7 Msun/Lsun at [3.6]. The SPARC data are publicly available and represent an ideal test-bed for models of galaxy formation.
We investigate a sub-sample of the rotation curves consisting of 45 HSB non-bulgy spiral galaxies selected from SPARC (Spitzer Photometry and Accurate Rotation Curves) database by using two dark halo models (NFW and Burkert) and MOdified Newtonian Dy
We present rotation curve fits to 175 late-type galaxies from the Spitzer Photometry & Accurate Rotation Curves (SPARC) database using seven dark matter (DM) halo profiles: pseudo-isothermal (pISO), Burkert, Navarro-Frenk-White (NFW), Einasto, Di Cin
A homogeneous sample of ~2200 low redshift disk galaxies with both high sensitivity long-slit optical spectroscopy and detailed I-band photometry is used to construct average, or template, rotation curves in separate luminosity classes, spanning 6 ma
We develop an analytic mass model for lensing galaxies, based on a broken power-law (BPL) density profile, which is a power-law profile with a mass deficit or surplus in the central region. Under the assumption of an elliptically symmetric surface ma
We study the kinematics and scaling relations of a sample of 43 giant spiral galaxies that have stellar masses exceeding $10^{11}$ $M_odot$ and optical discs up to 80 kpc in radius. We use a hybrid 3D-1D approach to fit 3D kinematic models to long-sl