English

On properties of a class of strong limits for supercritical superprocesses

Probability 2018-08-30 v2

Abstract

Suppose that X={Xt,t0;Pμ}X=\{X_t, t\ge 0; \mathbb{P}_{\mu}\} is a supercritical superprocess in a locally compact separable metric space EE. Let ϕ0\phi_0 be a positive eigenfunction corresponding to the first eigenvalue λ0\lambda_0 of the generator of the mean semigroup of XX. Then Mt:=eλ0tϕ0,XtM_t:=e^{-\lambda_0t}\langle\phi_0, X_t\rangle is a positive martingale. Let MM_\infty be the limit of MtM_t. It is known that MM_\infty is non-degenerate iff the LlogLL\log L condition is satisfied. When the LlogLL\log L condition may not be satisfied, we recently proved in (arXiv:1708.04422) that there exist a non-negative function γt\gamma_t on [0,)[0, \infty) and a non-degenerate random variable WW such that for any finite nonzero Borel measure μ\mu on EE, limtγtϕ0,Xt=W,\mboxa.s.Pμ. \lim_{t\to\infty}\gamma_t\langle \phi_0,X_t\rangle =W,\qquad\mbox{a.s.-}\mathbb{P}_{\mu}. In this paper, we mainly investigate properties of WW. We prove that WW has strictly positive density on (0,)(0,\infty). We also investigate the small value probability and tail probability problems of WW.

Keywords

Cite

@article{arxiv.1803.02973,
  title  = {On properties of a class of strong limits for supercritical superprocesses},
  author = {Yan-Xia Ren and Renming Song and Rui Zhang},
  journal= {arXiv preprint arXiv:1803.02973},
  year   = {2018}
}

Comments

Minor typos are corrected. The Chinese version will appear in Sci. Sin. Math