arXiv subjects

M. Sprenger

Publications and source records attributed to M. Sprenger.

5 recordsLinked to original sources

arXiv2014

The Bethe Roots of Regge Cuts in Strongly Coupled N=4 SYM Theory

We describe a general algorithm for the computation of the remainder function for n-gluon scattering in multi-Regge kinematics for strongly coupled planar N=4 super Yang-Mills theory. This regime is accessible through the infrared physics of an auxiliary quantum integrable system describing strings in AdS5xS5. Explicit formulas are presented for n=6 and n=7 external gluons. Our results are consistent with expectations from perturbative gauge theory. This paper comprises the technical details for the results announced in arXiv:1405.3658 .

hep-th↗

arXiv2014

Heptagon Amplitude in the Multi-Regge Regime

As we have shown in previous work, the high energy limit of scattering amplitudes in N=4 supersymmetric Yang-Mills theory corresponds to the infrared limit of the 1-dimensional quantum integrable system that solves minimal area problems in AdS5. This insight can be developed into a systematic algorithm to compute the strong coupling limit of amplitudes in the multi-Regge regime through the solution of auxiliary Bethe Ansatz equations. We apply this procedure to compute the scattering amplitude for n=7 external gluons in different multi-Regge regions at infinite 't Hooft coupling. Our formulas are remarkably consistent with the expected form of 7-gluon Regge cut contributions in perturbative gauge theory. A full description of the general algorithm and a derivation of results will be given in a forthcoming paper.

hep-th↗

arXiv2013

The Excited Hexagon Reloaded

This work revisits the computation of six-gluon scattering amplitudes in the high energy limit of strongly coupled N=4 supersymmetric Yang-Mills theory. It is based on previous studies in which we showed that the amplitude simplifies in the Regge regime and outlined an efficient computational scheme. By exploiting a symmetry of the underlying equations we are now able to argue that a term we had seen in preliminary numerical studies must vanish identically. The derived formula for the Regge limit of the 6-gluon scattering amplitude at strong coupling differs from the one we had conjectured previously.

hep-th↗

arXiv2012

Multi-Regge Limit of the n-Gluon Bubble Ansatz

We investigate n-gluon scattering amplitudes in the multi-Regge region of N=4 supersymmetric Yang-Mills theory at strong coupling. Through a careful analysis of the thermodynamic bubble ansatz (TBA) for surfaces in AdS5 with n-g(lu)on boundary conditions we demonstrate that the multi-Regge limit probes the large volume regime of the TBA. In reaching the multi-Regge regime we encounter wall-crossing in the TBA for all n>6. Our results imply that there exists an auxiliary system of algebraic Bethe ansatz equations which encode valuable information on the analytical structure of amplitudes at strong coupling.

hep-th↗

arXiv1999

Measurements of the radiation hardness of selected scintillating and light guide fiber materials

Radiation hardness studies of KURARAY SCSF-78M scintillating fibers and clear fibers from KURARAY and pol.hi.tech. performed under different dose rate conditions in proton and electron beams are summarized. For high dose rates in-situ measurements of the fiber light output were done. During several months after irradiation all fibers were measured concerning light emission and transparency. Fibers irradiated at high rates to about 1 Mrad are clearly damaged but recover within a few hours up to several weeks. Using smaller rates up to the same integral dose a decrease of the light output of scintillating fibers of up to 30% can not be excluded. Clear fibers seem to be uneffected up to 400 krad. No significant influence of fiber coverage and atmosphere during irradiation was found.

physics.ins-det↗