  We study the effects of accretion environment (gas density, temperature and
angular momentum) at large radii ($\sim 10$pc) on luminosity of hot accretion
flows. The radiative feedback effects from the accretion flow on the accretion
environment are also self-consistently taken into account. We find that the
slowly rotating flows at large radii can significantly deviate from Bondi
accretion when radiation heating and cooling are considered. We further find
that when the temperature of environment gas is low (e.g. $T=2\times 10^7$K),
the luminosity of hot accretion flows is high. When the temperature of gas is
high (e.g. $T\geq4\times 10^7$K), the luminosity of hot accretion flow
significantly deceases. The environment gas density can also significantly
influence the luminosity of accretion flows. When density is higher than $\sim
4\times 10^{-22}\text{g} \text{cm}^{-3}$ and temperature is lower than $2\times
10^7$K, hot accretion flow with luminosity lower than $2\%L_{\text{Edd}}$ is
not present. Therefore, the pc-scale environment density and temperature are
two important parameters to determine the luminosity. The results are also
useful for the sub-grid models adopted by the cosmological simulations.
