LHC String Phenomenology

TL;DR

This work tackles the deeper LHC inverse problem by proposing a framework to map semi-realistic string vacua to LHC signatures and to distinguish among string constructions using early LHC data. It demonstrates that different classes of string vacua (notably KKLT and Large Volume) plus eight string-motivated constructions yield finite, overlapping yet distinguishable signature footprints, which can be separated with about $5\,fb^{-1}$ of data and refined with more statistics. The approach relies on correlations between high-scale moduli stabilization, SUSY-breaking mediation, and low-energy soft-term patterns, translating microscopic theory into experimentally testable collider observables. The results provide a pragmatic path to connect string theory with collider data and motivate expanding the catalogue of vacua and signatures to sharpen discrimination in future analyses.

Abstract

We argue that it is possible to address the deeper LHC Inverse Problem, to gain insight into the underlying theory from LHC signatures of new physics. We propose a technique which may allow us to distinguish among, and favor or disfavor, various classes of underlying theoretical constructions using (assumed) new physics signals at the LHC. We think that this can be done with limited data $(5-10 fb^{-1})$, and improved with more data. This is because of two reasons -- a) it is possible in many cases to reliably go from (semi)realistic microscopic string construction to the space of experimental observables, say, LHC signatures. b) The patterns of signatures at the LHC are sensitive to the structure of the underlying theoretical constructions. We illustrate our approach by analyzing two promising classes of string compactifications along with six other string-motivated constructions. Even though these constructions are not complete, they illustrate the point we want to emphasize. We think that using this technique effectively over time can eventually help us to meaningfully connect experimental data to microscopic theory.

Figures (13)

• Figure 1: Cartoon to illustrate the method used to distinguish constructions.
• Figure 2: Plot of number of events with opposite-sign dileptons and $\geq$ 2 jets and number of events with three leptons and $\geq$ 2 jets. The black dot represents the lower limit of observability of the two signatures, according to conditions in equation (\ref{['observability']}). Note that the HM-A and overlaping HM-B and HM-C construction can be distinguished easily from the PH-A, PH-B, II-A, IIB-K and IIB-L constructions, as they occupy very different regions. The plots are best seen in color.
• Figure 3: Plot of number of events with clean dileptons and number of events with clean trileptons. "clean" means not accompanied by jets. The black dot represents the lower limit of observability of the two signatures, according to conditions in equation (\ref{['observability']}). The models below the observable limit have not been shown. Note that the HM-A and overlapping HM-B and HM-C constructions can be distinguished from the PH-A, PH-B, II-A and IIB-L constructions, since the latter are not observable with the given luminosity. The plots are best seen in color.
• Figure 4: Plot of number of events with 0 leptons, 1 or 2 b jets and $\geq$ 6 jets and number of events with 2 leptons, 0 b jets and $\geq$ 2 jets. The black dot represents the lower limit of observability of the two signatures, according to conditions in equation (\ref{['observability']}). The models below the observable limit have also been shown to emphasize that the II-A construction has very different number of events for these signatures compared to other constructions even without imposing the observability constraint. Note that the PH-B and II-A constructions can be distinguished from the PH-A, IIB-K and IIB-L constructions because they have very different slopes. The plots are best seen in color.
• Figure 5: Plot of number of events with 2 leptons, 0 b jets and $\geq$ 2 jets and number of events with 2 leptons, 1 or 2 b jets and $\geq$ 2 jets. The black dot represents the lower limit of observability of the two signatures, according to conditions in equation (\ref{['observability']}). The models below the observable limit have not been shown. Note that the PH-B and II-A constructions can be distinguished from each other since the former is not observable while the latter is observable. One can also partially distinguish the PH-A and IIB-L constructions. The plots are best seen in color.