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dSph Masses. Matthew Walker – IoA, Cambridge with Mario Mateo - U. Michigan Edward Olszewski - U. Arizona Jorge Peñarrubia - IoA Wyn Evans - IoA Gerry Gilmore - IoA --Stay tuned for Joe Wolf’s talk too--. Extreme Star Formation in Dwarf Galaxies Ann Arbor, 28 July, 2009.
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dSph Masses Matthew Walker – IoA, Cambridge with Mario Mateo - U. Michigan Edward Olszewski - U. Arizona Jorge Peñarrubia - IoA Wyn Evans - IoA Gerry Gilmore - IoA --Stay tuned for Joe Wolf’s talk too-- Extreme Star Formation in Dwarf Galaxies Ann Arbor, 28 July, 2009
Velocity Dispersion Profiles Walker etal (arXiv:0906.0341)
Kinematics with the Jeans Equation 1) Jeans Eq. (spherical) 2) Solution in terms of observables 3) Adopt Hernquist Halo Model Free Parameters V_max, r_scale, alpha, gamma, beta=constant --> Core --> NFW Cusp
Fornax: Vmax = 20 +/- 4 km/s arXiv:0906.0341
M(rhalf) for 8 “classical” dSphs • Robust to large ranges for r0, alpha, gamma, beta arXiv:0906.0341
Simple Mass Estimator Jeans Eq. Isotropy, flat vdisp profile -->
Simple Mass Estimator c.f. Strigari et al. 2008
Data for 28 Satellites arXiv:0906.0341
A Universal Mass Profile? arXiv:0906.0341
Velocity Dispersion vs. Size arXiv:0906.0341
Universal Mass Profile? arXiv:0906.0341
Scatter wrt Universal Profile and M300 arXiv:0906.0341