A window for cosmic strings
  Particle emission and gravitational radiation from cosmic string loops affect
the resulting loop distribution, and hence the corresponding observational
consequences of cosmic strings. Here we focus on models in which loops of all
sizes are produced from the infinite string network with a given power-law (the
Polchinski-Rocha loop production function). We find that, due to particle
production, the Stochastic Gravitational Wave Background (SGWB) is cut off at
frequencies larger than any current or planned GW experiment, meaning that
present constraints from the LIGO-Virgo-Kagra (LVK) collaboration still hold.
However, if a fraction $\gtrsim \mathcal{O}(10^{-3})$ of these particles
cascades into $\gamma$-rays, and if the gravitational backreaction scale
follows the Polchinski-Rocha model, then the string tension is tightly
constrained from below by measurements of the Diffuse $\gamma$-Ray Background,
and from above by the SGWB. With reasonable assumptions, the joint constraint
on the string tension set by these two possible observables reduces the
available parameter space to a narrow band. Future upgrades to LVK will either
rule out this model or detect strings.
