118719719
D0 dimuon charge asymmetry from $B_s$ system with Z′ couplings and the recent LHCb result
The D0 collaboration has announced the observation of the like-sign dimuon charge asymmetry since 2010, which has a difference of more than $3\ensuremath{\sigma}$ from the Standard Model prediction. One of the promising explanations is considering the existence of flavor-changing ${Z}^{\ensuremath{'}}$ couplings to the $b$ and $s$ quarks which can contribute to the off-diagonal decay width in the ${B}_{s}\ensuremath{-}{\overline{B}}_{s}$ mixing. Model construction is highly constrained by the recent LHCb data of $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ integrated luminosity. In this paper, we analyze the experimental constraints on constructing new physics models to explain the dimuon charge asymmetry from the $CP$ violation of the ${B}_{s}$ system. We present limits on ${Z}^{\ensuremath{'}}$ couplings and show that it is impossible to obtain the $1\ensuremath{\sigma}$ range of the dimuon charge asymmetry without the new contribution in the ${B}_{d}$ system. Even with an arbitrary contribution in the ${B}_{d}$ system, the new couplings must be in the fine-tuned region.
8099383
Gauge Messenger Models
We consider gauge messenger models in which X and Y gauge bosons and gauginos are messengers of supersymmetry breaking. In simple gauge messenger models, all the soft parameters except μ and Bμ are calculated in terms of a single scale parameter MSUSY which is proportional to F / MGUT. Unique prediction on dark matter in gauge messenger models is discussed. (Based on hep‐ph/0601036 and hep‐ph/0607169)
14499725
The mu problem and B and L conservation with a discrete gauged R symmetry
We examine in a generic context how the {mu} problem can be resolved by means of a spontaneously broken gauge symmetry. We then focus on the new scheme based on a discrete gauge R symmetry which is spontaneously broken by nonperturbative hidden sector dynamics triggering supersymmetry breaking also. The possibility to suppress the dangerous baryon and/or lepton-number-violating interactions by means of this discrete R symmetry is examined also together with some phenomenological consequences. {copyright} {ital 1997} {ital The American Physical Society}
119212900
Light neutralino dark matter with a very light Higgs boson for CoGeNT and DAMA/LIBRA data
Recently, the CoGeNT collaboration reported weakly interacting massive particle candidate-signal events exceeding the known backgrounds where the light WIMP with large cross section is supported. Motivated by this issue, we analyze a light neutralino dark matter scenario with a very light CP-even Higgs mediation in the elastic scattering process, which provides the mass and direct detection cross section to explain the CoGeNT result. To be compatible with the result of LEP experiments, the light CP-even Higgs is favored to be at around 9-10 GeV. Such a scenario can be realized in the "beyond the minimal supersymmetric standard model" context. The relic abundance consistent with the WMAP result can be obtained when twice neutralino mass is close to the light Higgs mass via the resonance enhancement of the annihilation cross section. As a result, the neutralino mass is predicted to be at around 5-6 GeV.
14019653
Top–bottom mass hierarchy, $s-\mu$ puzzle and gauge coupling unification with split multiplets
Abstract. Supersymmetric 5D SU(5) grand unification is considered. SU(5) is broken down to $G_{\mathrm{{SM}}}=SU(3)\times SU(2)\times U(1)$ by the $Z_2\times Z_2'$ assignment of the bulk field(s). The matter fields are located at the fixed point(s). In the bulk, a Higgs multiplet $\bar 5_H$ (containing the bottom doublet $H_1$) and the SU(5) gauge multiplet are located. At one fixed point, $H_2$ (the top doublet) and the standard model matter multiplets are presented. Because of the difference of the locations of $H_1$ and $H_2$, one can obtain a hierarchy between top and bottom Yukawa couplings. We also present a possible way to understand the s–$\mu$ mass puzzle in this framework of the split multiplet.
11210523
TeV scale 5D SU(3)W unification and the fixed point anomaly cancellation with chiral split multiplets
A possibility of 5D gauge unification of SU(2)L × U(1)Y in SU(3)W is examined. The orbifold compactification allows fixed points where SU(2)L × U(1)Y representations can be assigned. We present a few possibilities which give long proton lifetime, top-bottom mass hierarchy from geometry, and reasonable neutrino masses. In general, these chiral models can lead to fixed point anomalies. We can show easily, due to the simplicity of the model, that these anomalies are cancelled by the relevant Chern-Simons terms for all the models we consider. It is also shown that the fixed point U(1)-graviton-graviton anomaly cancels without the help from the Chern-Simons term. Hence, we conjecture that the fixed point anomalies can be cancelled if the effective 4D theory is made anomaly free by locating chiral fermions at the fixed points.
118415614
On instantons as Kaluza-Klein modes of M5-branes
A bstractInstantons and W-bosons in 5d maximally supersymmetric Yang-Mills theory arise from a circle compactification of the 6d (2,0) theory as Kaluza-Klein modes and winding self-dual strings, respectively. We study an index which counts BPS instantons with electric charges in Coulomb and symmetric phases. We first prove the existence of unique threshold bound state of (noncommutative) U(1) instantons for any instanton number, and also show that charged instantons in the Coulomb phase correctly give the degeneracy of SU(2) self-dual strings. By studying SU(N) self-dual strings in the Coulomb phase, we find novel momentum-carrying degrees on the worldsheet. The total number of these degrees equals the anomaly coefficient of SU(N) (2,0) theory. We finally show that our index can be used to study the symmetric phase of this theory, and provide an interpretation as the superconformal index of the sigma model on instanton moduli space.
15931690
Track extrapolation and distribution for the CDF-II trigger system
Abstract The CDF-II experiment is a multipurpose detector designed to study a wide range of processes observed in the high energy proton–antiproton collisions produced by the Fermilab Tevatron. With event rates greater than 1 MHz, the CDF-II trigger system is crucial for selecting interesting events for subsequent analysis. This document provides an overview of the Track Extrapolation System (XTRP), a component of the CDF-II trigger system. The XTRP is a fully digital system that is utilized in the track-based selection of high momentum lepton and heavy flavor signatures. The design of the XTRP system includes five different custom boards utilizing discrete and FPGA technology residing in a single VME crate. We describe the design, construction, commissioning and operation of this system.
62550986
Cyberinfrastructure for high energy physics in Korea
We introduce the hierarchy of cyberinfrastructure which consists of infrastructure (supercomputing and networks), Grid, e-Science, community and physics from bottom layer to top layer. KISTI is the national headquarter of supercomputer, network, Grid and e-Science in Korea. Therefore, KISTI is the best place to for high energy physicists to use cyberinfrastructure. We explain this concept on the CDF and the ALICE experiments. In the meantime, the goal of e-Science is to study high energy physics anytime and anywhere even if we are not on-site of accelerator laboratories. The components are data production, data processing and data analysis. The data production is to take both on-line and off-line shifts remotely. The data processing is to run jobs anytime, anywhere using Grid farms. The data analysis is to work together to publish papers using collaborative environment such as EVO (Enabling Virtual Organization) system. We also present the global community activities of FKPPL (France-Korea Particle Physics Laboratory) and physics as top layer.
121615298
Measurement of the refractive index of the LAB-based liquid scintillator and acrylic at RENO
In this paper, we describe the first measurement of the refractive index of the linear alkyl benzene (LAB)-based liquid scintillator and acrylic used at the Reactor Experiment for Neutrino Oscillation (RENO). The refractive index of a material is an important optical property and the prism spectrometer is the most common device for measuring the refractive index. Using the minimum deviation technique, which requires an exact measurement of the apex angle, we determined the refractive indices at six different wavelengths and then fitted them. We also compared the refractive index of the LAB-based liquid scintillator with the refractive indices of other liquid scintillator solvents commonly used in reactor neutrino experiments.
119212917
Natural inflation with multiple sub-Planckian axions
We extend the Kim-Nilles-Peloso (KNP) alignment mechanism for natural inflation to models with $N>2$ axions, which obtains a super-Planckian effective axion decay constant $f_{\textrm{eff}}\gg M_{Pl}$ through an alignment of the anomaly coefficients of multiple axions having sub-Planckian fundamental decay constants $f_0\ll M_{Pl}$. The original version of the KNP mechanism realized with two axions requires that some of the anomaly coefficients should be of the order of $f_{\textrm{eff}}/f_0$, which would be uncomfortably large if $f_{\rm eff}/f_0 \gtrsim {\cal O}(100)$ as suggested by the recent BICEP2 results. We note that the KNP mechanism can be realized with the anomaly coefficients of $\mathcal{O}(1)$ if the number of axions $N$ is large as $N\ln N\gtrsim 2\ln (f_{\textrm{eff}}/f_0)$, in which case the effective decay constant can be enhanced as $f_{\rm eff}/f_0 \sim \sqrt{N !}\,n^{N-1}$ for $n$ denoting the typical size of the integer-valued anomaly coefficients. Comparing to the other multiple axion scenario, the N-flation scenario which requires $N \sim f_{\textrm{eff}}^2/f_0^2$, the KNP mechanism has a virtue of not invoking to a too large number of axions, although it requires a specific alignment of the anomaly coefficients, which can be achieved with a probability of ${\cal O}(f_0/f_{\rm eff})$ under a random choice of the anomaly coefficients. We also present a simple model realizing a multiple axion monodromy along the inflaton direction.