The decay of massive closed superstrings with maximum angular momentum

TL;DR

This paper investigates the decay behavior of highly massive closed superstrings with maximum angular momentum, revealing that their lifetime increases linearly with mass and that decay channels are highly selective in mass distribution.

Contribution

It provides a detailed analysis of decay rates and channels for massive closed superstrings, highlighting a linear lifetime dependence on mass and the uniqueness of decay channels at large masses.

Findings

Lifetime grows linearly with mass (T = c α' M).

Decay channels are highly selective, with one mass determined by the other.

Decay into specific channels is exponentially suppressed for certain states.

Abstract

We study the decay of a very massive closed superstring (i.e. \alpha' M^2>> 1) in the unique state of maximum angular momentum. This is done in flat ten-dimensional spacetime and in the regime of weak string coupling, where the dominant decay channel is into two states of masses M_1, M_2. We find that the lifetime surprisingly grows with the first power of the mass M: T =c \alpha' M. We also compute the decay rate for each values of M_1, M_2. We find that, for large M, the dynamics selects only special channels of decay: modulo processes which are exponentially suppressed, for every decay into a state of given mass M_1, the mass M_2 of the other state is uniquely determined.