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تسجيل مستخدم جديدPipe3D Stellar and Gaseous Velocity Dispersions for CALIFA Galaxies
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We present tables of velocity dispersions derived from CALIFA V1200 datacubes using Pipe3D. Four different dispersions are extracted from emission (ionized gas) or absorption (stellar) spectra, with two spatial apertures (5 and 30). Stellar and ionized gas dispersions are not interchangeable and we determine their distinguishing features. We also compare these dispersions with literature values and construct sample scaling relations to further assess their applicability. We consider revised velocity-based scaling relations using the virial velocity parameter S_K^2 = K V_rot^2 + sigma^2 constructed with each of our dispersions. Our search for the strongest linear correlation between S_K and i-band absolute magnitudes favors the common K ~ 0.5, though the range 0.3 - 0.8 is statistically acceptable. The reduction of scatter in our best stellar mass-virial velocity relations over that of a classic luminosity-velocity relation is minimal; this may however reflect the dominance of massive spirals in our sample.
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