LHC Phenomenology of an Extended Standard Model with a Real Scalar Singlet

Gauge singlet extensions of the Standard Model (SM) scalar sector may help remedy its theoretical and phenomenological shortcomings while solving outstanding problems in cosmology. Depending on the symmetries of the scalar potential, such extensions may provide a viable candidate for the observed relic density of cold dark matter or a strong first order electroweak phase transition needed for electroweak baryogenesis. Using the simplest extension of the SM scalar sector with one real singlet field, we analyze the generic implications of a singlet-extended scalar sector for Higgs boson phenomenology at the Large Hadron Collider (LHC). We consider two broad scenarios: one in which the neutral SM Higgs and singlet mix and the other in which no mixing occurs and the singlet can be a dark matter particle. For the first scenario, we analyze constraints from electroweak precision observables and their implications for LHC Higgs phenomenology. For models in which the singlet is stable, we determine the conditions under which it can yield the observed relic density, compute the cross sections for direct detection in recoil experiments, and discuss the corresponding signatures at the LHC.Comment: 39 pages, 11 figures, 2 table

Electroweak Beautygenesis: From b {\to} s CP-violation to the Cosmic Baryon Asymmetry

We address the possibility that CP-violation in $B_s-\bar B_s$ mixing may help explain the origin of the cosmic baryon asymmetry. We propose a new baryogenesis mechanism - "Electroweak Beautygenesis" - explicitly showing that these two CP-violating phenomena can be sourced by a common CP-phase. As an illustration, we work in the Two-Higgs-Doublet model. Because the relevant CP-phase is flavor off-diagonal, this mechanism is less severely constrained by null results of electric dipole moment searches than other scenarios. We show how measurements of flavor observables by the D0, CDF, and LHCb collaborations test this scenario.Comment: 4 pages, 1 figure, 1 tabl

Global Analysis of Nucleon Strange Form Factors at Low Q2Q^2

We perform a global analysis of all recent experimental data from elastic parity-violating electron scattering at low $Q^2$. The values of the electric and magnetic strange form factors of the nucleon are determined at $Q^2 = 0.1$ GeV/$c^2$ to be $G^s_E = -0.008 \pm 0.016$ and $G^s_M = 0.29 \pm 0.21$.Comment: 8 pages, 1 figur

Some Effects of Extreme Shortening on Frog Skeletal Muscle

We have established that the sarcolemma of frog skeletal muscle is so firmly tied in at each sarcomere level near the M line, as well as near the Z line, that it is thrown into folds or festoons when the fibers shorten. The attachment is not broken even when the fibers shorten to 25% of optimum tension length. Such extreme shortening affects both the morphology and physiology of the muscle; the morphological change seems to be limited to the myofilaments. The physiological effects in frog sartorius muscle include an increase in resting oxygen consumption and changes in the relation between fiber length and isometric tension similar to those found in isolated muscle fibers

Biodegradable Shooting Targets Acidify Soils, Limit Plant Growth, and Mobilize Lead

Environmental waste from recreational shotgun shooting includes lead pellet and target debris. The main risk of lead pellets is that they can be ingested by birds as they swallow pebbles and grit that aid in digestion. Another possible vector of toxicity is when acidic soil conditions mobilize lead ions from the solid pellets into the soil and groundwater. Historically, secondary waste resulted from petroleum pitch based targets that persisted in the environment for years. To reduce the environmental lifetime of targets, biodegradable targets were developed. At a former sporting clay shooting range in Florence, Montana, we found that as biodegradable targets degraded, their sulfuric components oxidized to release acid; as a result, soil pH was as low as 2. Target abundance correlated with decreased soil pH (?=-0.681, P<0.001) and decreased plant cover (p=-0.770, P<0.001). These acidic soils increased the mobility of lead from shot pellets and now lead concentrations exceed background. Our results demonstrate that biodegradable shooting targets exacerbate the environmental hazards that result from lead shotfall. Careful considerations regarding target composition and shooting locations may minimize environmental exposure to toxicants

Maximum Strength, Rate of Force Development, Jump Height, and Peak Power Alterations in Weightlifters across Five Months of Training

The purpose of this monitoring study was to investigate how alterations in training affect changes in force-related characteristics and weightlifting performance. Subjects: Seven competitive weightlifters participated in the study. Methods: The weightlifters performed a block style periodized plan across 20 weeks. Force plate data from the isometric mid-thigh pull and static jumps with 0 kg, 11 kg, and 20 kg were collected near the end of each training block (weeks 1, 6, 10, 13, 17, and 20). Weightlifting performance was measured at weeks 0, 7, 11, and 20. Results: Very strong correlations were noted between weightlifting performances and isometric rate of force development (RFD), isometric peak force (PF), peak power (PP), and jump height (JH). Men responded in a more predictable manner than the women. During periods of higher training volume, RFD was depressed to a greater extent than PF. JH at 20 kg responded in a manner reflecting the expected fatigue response more so than JH at 0 kg and 11 kg. Conclusions: PF appears to have been more resistant to volume alterations than RFD and JH at 20 kg. RFD and JH at 20 kg appear to be superior monitoring metrics due to their “sensitivity.

Nuclear-level Effective Theory of Muon-to-Electron Conversion: Formalism and Applications

New mu-to-e conversion searches aim to advance limits on charged lepton flavor violation (CLFV) by four orders of magnitude. By considering P and CP selection rules and the structure of possible charge and current densities, we show that rates are governed by six nuclear responses. To generate a microscopic formulation of these responses, we construct in non-relativistic effective theory (NRET) the CLFV nucleon-level interaction, then embed it in a nucleus. We discuss previous work, noting the lack of a systematic treatment of the various small parameters. Because the momentum transfer is comparable to the inverse nuclear size, a full multipole expansion of the response functions is necessary, a daunting task with Coulomb-distorted electron partial waves. We perform such an expansion to high precision by introducing a simplifying local electron momentum, treating the full set of 16 NRET operators. Previous work has been limited to the simplest charge/spin operators, ignored Coulomb distortion (or alternatively truncated the partial wave expansion) and the nucleon velocity operator, which is responsible for three of the response functions. This generates inconsistencies in the treatment of small parameters. We obtain a "master formula" for mu-to-e conversion that properly treats all such effects and those of the muon velocity. We compute muon-to-electron conversion rates for a series of experimental targets, deriving bounds on the coefficients of the CLFV operators. We discuss the nuclear physics: two types of coherence enhance certain CLFV operators and selection rules blind elastic mu-to-e conversion to others. We discuss the matching of the NRET onto higher level EFTs, and the relation to mu-to-e conversion to other CLFV tests. Finally we describe a publicly available script that can be used to compute mu-to-e conversion rates in nuclear targets.Comment: 50 pages, 10 figures; a few typos fixed in v

Weak mixing angle at low energies

We determine the weak mixing angle in the MS-bar scheme at energy scales relevant for present and future low energy electroweak measurements. We relate the renormalization group evolution of the weak mixing angle to the corresponding evolution of the QED coupling and include higher-order terms in alpha_s and alpha that had not been treated in previous analyses. We also up-date the analysis of non-perturbative hadronic contributions and argue that the associated uncertainty is small compared to anticipated experimental errors. The resulting value of the low-energy weak mixing angle is sin^2 theta_W (0) = 0.23867 +- 0.00016.Comment: 21 pages; 1 figure and some references added, some changes in text; final version as publishe

High electric field strength two-dimensional peptide separations using a microfluidic device: Microfluidics and Miniaturization

New instrumentation has been developed to improve the resolution, efficiency, and speed of microfluidic two-dimensional separations using micellar electrokinetic chromatography (MEKC) coupled to high field strength capillary electrophoresis (CE). Previously published two-dimensional separation instrumentation [1] from our group was limited to a maximum potential difference of 8.4 kV, resulting in an electric field strength of only ~200 V/cm in the first dimension. The circuit described in this report has been designed to couple a higher voltage supply with a rapidly switching, lower voltage supply to utilize the best features of each. Voltages applied in excess of 20 kV lead to high electric field strength separations in both dimensions, increasing the separation resolution, efficiency, and peak capacity while reducing the required analysis time. Detection rates as high as 6 peptides per second (based on total analysis time) were observed for a model protein tryptic digest separation. Additionally, higher applied voltages used in conjunction with microfluidic chips with longer length channels maintained higher electric field strengths and produced peak capacities of over 4,000 for some separations. Total separation time in these longer channel devices was comparable to that obtained in short channels at low field strength; however, resolving power improved approximately 3 fold

Sex expression and sexual dimorphism is subdioecious 'Wurmbea dioica' (Colchicaceae)

Subdioecy is a sexual system with male, female, and hermaphrodite phenotypes and is often considered a transitory stage in the evolution of full dioecy. Here, we examine sex ratios, sex expression, and sexual dimorphism in three subdioecious populations of 'Wurmbea dioica' to gain insight into the stability of this sexual system. Sex ratios in the field were slightly male biased: 50% males, 43% females, and 7% hermaphrodites. Sex expression of females was constant for 3 yr under favorable glasshouse conditions. Male sex expression was labile, and 71% of males became hermaphrodites. Hermaphrodites remained unchanged, probably in response to the favorable conditions. In the field, estimates of femaleness of hermaphrodites tended toward maleness (Gp0.31). Females produced three times more seeds per plant than did hermaphrodites. This increased fecundity resulted from females producing more ovuliferous flowers per plant and more ovules per flower but fewer aborted seeds (21% vs. 51%). Hermaphrodites were self-compatible, and their lower seed set may reflect inbreeding depression and/or differences in allocation patterns compared with females. Males produced 1.3 times more pollen per flower that was 7% more viable than did hermaphrodites, indicating resource-based trade-offs between male and female functions when males produced functional pistils. Males produced flowers that were slightly larger in diameter than those of hermaphrodites, and flowers of both were 1.3 times larger than those of females. Males and hermaphrodites produced similar numbers of flowers, both producing more than females. Fecundity differences between females and hermaphrodites are consistent with models for the maintenance of constant females. Male sex lability may be advantageous if male fitness gain curves decelerate in response to increased resource availability and seed production augments plant fitness. This is consistent with resource-based threshold models of male gender modification