A note on the critical barrier for the survival of $α-$stable branching random walk with absorption
We consider a branching random walk with an absorbing barrier, where the step of the associated one-dimensional random walk is in the domain of attraction of an $α$-stable law with $1<α<2$. We shall prove that there is a barrier $an^{\frac{1}{1+α}}$ and a critical value $a_α$ such that if $a a_α$, then the process survives. The results generalize previous results in literature for the case $α=2$.