Role of CISS in the Radical Pair Model of Avian Magnetoreception

Abstract: In this paper, we investigate the effect of chiral-induced spin selectivity (CISS) on the radical pair model of avian magnetoreception. We examine the impact of spin selectivity on the avian compass sensitivity. In this analysis, we also consider the dipolar and exchange interactions and observe their interplay with CISS. We find that CISS results in multifold increase in avian compass sensitivity. Interestingly, we also observe that CISS can counter the deleterious effect of dipolar interaction and increase system sensitivity.The analysis has been performed for both the toy model (only 1 nucleus) and a more general case where we consider 4-nuclei from the cryptochrome radical pair system. We observe that the CISS allows the radical pair model to have a more realistic rate with good sensitivity. We also do analysis of functional window of avian compass reported in behavioral experiments in functional window. We could not find a parameter set where functional window can be observed along with CISS.