The Baryonic Tully-Fisher Relation in the Local Group and the Equivalent Circular Velocity of Pressure Supported Dwarfs

Abstract

We explore the Baryonic Tully-Fisher Relation in the Local Group. Rotationally supported Local Group galaxies adhere precisely to the relation defined by more distant galaxies. For pressure supported dwarf galaxies, we determine the scaling factor ${\beta }_c$ that relates their observed velocity dispersion to the equivalent circular velocity of rotationally supported galaxies of the same mass such that $V_o={\beta }_c{\sigma }_{\ast }$. For a typical mass-to-light ratio ${{\rm Y}}_{\ast }=2{\mathrm{M}}_{\odot }/{\mathrm{L}}_{\odot }$ in the $V$-band, we find that ${\beta }_c=2$. More generally, $\log {\beta }_c=0.25\log {{\rm Y}}_{\ast }+0.226$. This provides a common kinematic scale relating pressure and rotationally supported dwarf galaxies.

14 pages, 4 figures. Accepted for publication in the Astronomical Journal

References in corpus (20)

• SPARC: Mass Models for 175 Disk Galaxies with Spitzer Photometry and Accurate Rotation Curves
• The SAURON project -- X. The orbital anisotropy of elliptical and lenticular galaxies: revisiting the (V/sigma,epsilon) diagram with integral-field stellar kinematics
• High-resolution mass models of dwarf galaxies from LITTLE THINGS
• One Law To Rule Them All: The Radial Acceleration Relation of Galaxies
• The DART imaging and CaT survey of the Fornax Dwarf Spheroidal Galaxy
• Velocity Dispersion Profiles of Seven Dwarf Spheroidal Galaxies
• Color--Mass-to-Light Ratio Relations for Disk Galaxies
• Weighing Galaxy Disks with the Baryonic Tully-Fisher Relation
• Testing the Strong Equivalence Principle: Detection of the External Field Effect in Rotationally Supported Galaxies
• Using The Baryonic Tully-Fisher Relation to Measure $H_o$
• LITTLE THINGS in 3D: robust determination of the circular velocity of dwarf irregular galaxies
• Andromeda Dwarfs in Light of MOND
• Dynamical signatures of a LCDM-halo and the distribution of the baryons in M33
• Predictions and Outcomes for the Dynamics of Rotating Galaxies
• First Gaia Local Group Dynamics: Magellanic Clouds Proper Motion and Rotation
• HST Proper Motions of NGC 147 and NGC 185: Orbital Histories and Test of Dynamically Coherent Andromeda Satellite Plane
• The Initial Mass Function of the Inner Galaxy Measured From OGLE-III Microlensing Timescales
• Orbital Torus Imaging: Using Element Abundances to Map Orbits and Mass in the Milky Way
• The Imprint of Spiral Arms on the Galactic Rotation Curve
• The Challenge to MOND from ultra faint dwarf galaxies

Cited by in corpus (5)

• From galactic bars to the Hubble tension: weighing up the astrophysical evidence for Milgromian gravity
• The distribution and morphologies of Fornax Cluster dwarf galaxies suggest they lack dark matter
• Probing the radial acceleration relation and the strong equivalence principle with the Coma cluster ultra-diffuse galaxies
• Calibrating cosmological simulations with implicit likelihood inference using galaxy growth observables
• Characteristics of Effective Dark Matter in Nonlocal Gravity