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Table 3

Mean (and median) observed kinematic properties for low-z comparison samples from the literature.

Sample SFR v σ v/σ R eff M dyn
[M yr-1] (km s-1) (km s-1) (kpc) (1010M)
(1) (2) (3) (4) (5) (6) (7)

Spiral 1.8 ± 0.4 (0.7) 162 ± 7 (143) 24 ± 0.5 (24) 7.0 ± 0.3 (6.3) 5.5 ± 0.3 (4.8) 11.5 ± 1.5 (4.9)

E/S0 0.12 ± 0.04 (0.08) 47 ± 4 (44) 162 ± 9 (163) 0.34 ± 0.03 (0.34) 2.9 ± 0.3 (2.4) 13.8 ± 3.2 (6.9)

LBA 26.7 ± 7.1 (17.0) 67 ± 11 (63) 71 ± 6 (67) 0.95 ± 0.11(1.1) 1.4 ± 0.1 (1.5) 1.0 ± 0.2 (1.0)

Notes. Column (1): low-z sample: spiral sample is drawn from Epinat et al. (2010), E/S0 from Cappellari et al. (2007) and LBAs from Gonçalves et al. (2010). Column (2): star formation rate (SFR). For spirals, it has been derived using only 50 objects, for which the SFRs have been computed from Hα measurements by James et al. (2004) using Salpeter IMF (Salpeter 1955) and applying the Kennicutt et al. (1994) relation. For E/S0 galaxies we considered the SFR computed in Shapiro et al. (2010) for a subsample of 13 sources using the Spitzer/IRAC data at 8.0 μm. They have calibrated this relation from the Yun et al. (2001) relation between SFR and radio continuum. If the Kennicutt (1998) SFR-Hα conversion is applied to calibrate the 8.0 μm SFR estimator, the SFR would lower by ~13% (see Wu et al. 2005). For the LBAs, the star formation rates are measured by Gonçalves et al. (2010) from combined Hα and MIPS 24 μm data using Kroupa (2008) IMF. The resulting SFRs are lower by a factor of ~1.5 compared to a Salpeter (1955) IMF. Column (3): observed velocity amplitude obtained as follows: for spirals, it is the observed maximum rotational velocity; for the E/S0 sample it is the luminosity-weighted squared velocity (i.e., ) within 1 Reff; for LBAs the velocity amplitude has been defined as the vshear in this work. Column (4): velocity dispersion derived as follows: for spirals, it is the (uniformly weighted) mean velocity dispersion; for E/S0s it is the luminosity-weighted squared velocity dispersion (i.e., ) within 1 Reff; for LBAs the velocity dispersion is the average velocity dispersion of each spaxel, weighted by flux. Column (5): dynamical ratio determined as the ratio between the values shown in Cols. (3) and (4). Column (6): effective radius for the different samples. For spirals it has been derived as half of the optical radius (Ropt) associated with the isophotal level at 25 mag arcsec-2 in the B-band, where Ropt = 1.9 × Reff (see Epinat et al. 2009); for E/S0 the half-light radius is measured in the I-band from WFPC2/HST images; for LBAs the effective radius was derived by selecting N spaxels with S   ! N > 6 such that (see Law et al. 2007). Column (7): dynamical mass determined as follows: for spirals we compute the total mass using the formula employed in their paper for rotation-dominated objects; we compute the dynamical masses for E/S0 using the formula Kσ2Reff/G as explained in Cappellari et al. (2006); finally, the dynamical masses of LBAs have been derived in Gonçalves et al. (2010) using the formula 5σ2Reff/G.

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