Effective field theory analysis on μ problem in low-scale gauge mediation
Supersymmetric models based on the scenario of gauge mediation often suffer from the well-known μ problem. In this paper, we reconsider this problem in low-scale gauge mediation in terms of effective field theory analysis. In this paradigm, all high energy input soft mass can be expressed via loop expansions. If the corrections coming from messenger thresholds are small, as we assume in this letter, then all RG evaluations can be taken as linearly approximation for low-scale supersymmetric breaking. Due to these observations, the parameter space can be systematically classified and studied after constraints coming from electro-weak symmetry breaking are imposed. We find that some old proposals in the literature are reproduced, and two new classes are uncovered. We refer to a microscopic model, where the specific relations among coefficients in one of the new classes are well motivated. Also, we discuss some primary phenomenologies.

title: Electroweak precision tests on the MSSM and NMSSM constrained at the LHC
abstract: A bstractFollowing previous works regarding electroweak precision tests in supersymmetry, we continue to explore their implications to the MSSM and NMSSM both of which are tightly constrained by the Higgs mass and its decay experiments at the LHC. We adopt universal squark, slepton mass of three generations, and A-term of all SM fermions. We determine the flows of both MSSM and NMSSM in the S-T plane with increasing tan β and/or γγ rate. Either increasing the value of Rγ or tan β, we find that the benchmark points tend to be pushed outside the contour at 99% CL in the MSSM, however, conversely they tend to shrink towards to the SM reference point in the NMSSM. In particular, our benchmark points suggest that tan β ≳ 50 is excluded at 99% CL by EWPTs for the MSSM in regions of parameter space which predict Rγ ≳ 1.3 due to this behavior. This behavior is also useful to distinguish the NMSSM from the MSSM. A byproduct is that the contributions coming from the neutralinos and charginos should be more suppressed in the MSSM in comparison with the NMSSM.

title: Mass Hierarchies with $m_{h}=125$ GeV from Natural SUSY
abstract: Our study starts with a sequence of puzzles that include $(a)$ at which level $\mu$ problem involving electroweak symmetry breaking can be solved; $(b)$ in which paradigm masses of superpartners in the third family can be lighter than in the first two families; $(c)$ whether it is possible to accommodate 125 GeV Higgs boson simultaneously; and $(d)$ how natural such paradigm is. These issues are considered in the context of two-site SUSY models. Both the MSSM and NMSSM as low-energy effective theory below the scale of two-site gauge symmetry breaking are investigated. We find that the fine tuning can be indeed reduced in comparison with ordinary MSSM with $m_{h}=125$ GeV. In general, the fine tuning parameter $\Delta$ is in the range of $20-400$.

title: R-symmetric Gauge Mediation With Fayet-Iliopoulos Term
abstract: We have studied R-symmetrc gauge mediation models with Fayet-Iliopoulos terms. We give a concrete example of hidden sector with an U(1)H gauge theory and a Fayet-Iliopoulos term, which can induce distinctive soft terms in the visible sector, and help solving fine tuning problems in models of R-symmetric gauge mediation.

title: Variant supercurrents and linearized supergravity
abstract: In this paper, the variant supercurrents based on consistency and completion in off-shell supergravity are studied. We formulate the embedding relations for supersymmetric current and energy tensor into a supercurrent multiplet. Corresponding linearized supergravity is obtained with an appropriate choice of the Wess–Zumino gauge in each gravity supermultiplet.

title: Phenomenologies of Higgs messenger models
abstract: In this paper, we investigate the phenomenologies of models where the Higgs sector plays the role of messengers in gauge mediation. The minimal Higgs sector and its extension are considered respectively. We find that there exist viable models when an appropriate parity is imposed. Phenomenological features in these kind of models include three approximate sum rules for scalar masses, light gluino as well as one-loop µ and two-loop Bµ terms.

title: The BES upgrade
abstract: The Beijing Spectrometer (BES) detector is a general purpose solenoid detector at the Beijing Electron Positron Collider (BEPC) in Beijing, China, that has collected large numbers of J/ψ, ψ′, D s , D and τ events. In this paper, we describe the recent upgrade of the initial BES detector (BESI) to the improved BESII detector.

title: Calibration of BC501A liquid scintillator cells with monochromatic neutron beams
abstract: The recoil proton energy response has been measured by exposing cylindrical cells, filled with BC501A BICRON liquid scintillator, to mono-energetic neutron reference fields. We determine the required calibration parameters and report the detailed procedures for the experimental data handling. A dedicated Monte Carlo simulation of the detector response and efficiency has been performed. It showed good agreement with the measured quantities. The results from this calibration are necessary for a detailed study of the neutron spectrum at the underground Gran Sasso Laboratory, with a neutron detector made of 32 liquid scintillator cells, like those used during the calibration.