||The Black Hole Mass Function Derived from Local Spiral Galaxies
||480, Structure and Dynamics of Disk Galaxies
||Davis, B. L.; Berrier, J. C.; Johns, L.; Shields, D. W.; Hartley, M. T.; Kennefick, D.; Kennefick, J.; Seigar, M. S.; Lacy, C. H. S.
||We present our determination of the nuclear supermassive black hole mass
function for spiral galaxies in the Local Universe, established from a
volume-limited sample consisting of a statistically complete collection
of the brightest spiral galaxies in the Southern (δ < 0°)
Hemisphere. The sample is defined by a limiting luminosity
(redshift-independent) distance, DL = 25.400 Mpc (z = 0.0057168)
and a limiting absolute B-band magnitude, ℳB = –19.1223.
These limits define a sample of 140 spiral galaxies, with 128 measurable
pitch angles to establish the pitch angle distribution for this sample.
This pitch-angle distribution function may be useful in the study of
the morphology of late-type galaxies.
We then use an established relationship between the logarithmic spiral arm
pitch angle and the mass of the central supermassive black hole in a host
galaxy in order to estimate the mass of the 128 respective supermassive
black holes in this volume-limited sample. This result effectively gives
us the distribution of mass for supermassive black holes residing in spiral
galaxies over a lookback time, tL ≤ 82.140 h67.77–1
Myr and contained within a comoving volume, VC = 3.3739 ×
104 h67.77–3 Mpc3. We estimate the density of supermassive
black holes residing in spiral galaxies in the Local Universe is ρ =
5.54–2.73+6.55 × 104 h67.773 M☉ Mpc–3. Thus, our derived cosmological supermassive black hole mass density for spiral galaxies is ΩBH = 4.35–2.15+5.14 × 10–7 h67.77. Assuming black holes grow via baryonic accretion, we predict that 0.0020–0.0010+0.0023 h67.773 % of the universal baryonic inventory (ΩBH/ωb) is confined within nuclear supermassive black holes at the center of spiral galaxies.