We investigate the stationary, spherically symmetric accretion of the collisionless Vlasov gas onto a Bardeen regular black hole. Compared with previous studies, we propose a model in which the total angular momentum of the gas particles is not uniformly distributed, instead a half-normal distribution is assumed. It is found that the regularizing parameter in the Bardeen metric have no remarkable influence on the accretion of the gas, but the distribution of the total angular momentum can heavily depress the mass accretion rate. This effect might be useful to understand the observed low luminosity of Sgr A* and other underluminous sources such as M87*.

We investigate the stationary, spherically symmetric accretion of the collisionless Vlasov gas onto a Bardeen regular black hole. Compared with previous studies, we propose a model in which the total angular momentum of the gas particles is not uniformly distributed, instead a half-normal distribution is assumed. It is found that the regularizing parameter in the Bardeen metric have no remarkable influence on the accretion of the gas, but the distribution of the total angular momentum can heavily depress the mass accretion rate. This effect might be useful to understand the observed low luminosity of Sgr A* and other underluminous sources such as M87*.