Persistent superfluid flow arising from the He-McKellar-Wilkens effect in molecular dipolar condensates

We show that the He-McKellar-Wilkens effect can induce a persistent flow in a Bose-Einstein condensate of polar molecules confined in a toroidal trap, with the dipolar interaction mediated via an electric dipole moment. For Bose-Einstein condensates of atoms with a magnetic dipole moment, we show that although it is theoretically possible to induce persistent flow via the Aharonov-Casher effect, the strength of electric field required is prohibitive. We also outline an experimental geometry tailored specifically for observing the He-McKellar-Wilkens effect in toroidally-trapped condensates.Comment: 5 pages 2 figure

Suppressing Proton Decay By Separating Quarks And Leptons

Arkani-Hamed and Schmaltz (AS) have shown that proton stability need not originate from symmetries in a high energy theory. Instead the proton decay rate is suppressed if quarks and leptons are spatially separated in a compact extra dimension. This separation may be achieved by coupling five dimensional fermions to a bulk scalar field with a non-trivial vacuum profile and requires relationships between the associated quark and lepton Yukawa couplings. We hypothesise that these relationships are the manifestation of an underlying symmetry. We further show that the AS proposal may suggest that proton stability \emph{is} the result of an underlying symmetry, though not necessarily the traditional baryon number symmetry.Comment: 4 pages, references added to match published versio

Electric dipole rovibrational transitions in HD molecule

The rovibrational electric dipole transitions in the ground electronic state of the HD molecule are studied. A simple, yet rigorous formula is derived for the transition rates in terms of the electric dipole moment function $D(R)$, which is calculated in a wide range of $R$. Our numerical results for transition rates are in moderate agreement with experiments and previous calculations, but are at least an order of magnitude more accurate.Comment: 7 pages, 1 figur

Infrared spectra of C2H4 dimer and trimer

Spectra of ethylene dimers and trimers are studied in the nu11 and (for the dimer) nu9 fundamental band regions of C2H4 (~2990 and 3100 cm-1) using a tunable optical parametric oscillator source to probe a pulsed supersonic slit jet expansion. The deuterated trimer has been observed previously, but this represents the first rotationally resolved spectrum of (C2H4)3. The results support the previously determined cross-shaped (D2d) dimer and barrel-shaped (C3h or C3) trimer structures. However, the dimer spectrum in the nu9 fundamental region of C2H4 is apparently very perturbed and a previous rotational analysis is not well verified.Comment: 21 pages, 4 figure

Quark-Lepton Symmetry In Five Dimensions

We construct a complete five dimensional Quark-Lepton symmetric model, with all fields propagating in the bulk. The extra dimension forms an $S^1/Z_2\times Z_2'$ orbifold with the zero mode fermions corresponding to standard model quarks localised at one fixed point. Zero modes corresponding to left(right)-chiral leptons are localised at (near) the other fixed point. This localisation pattern is motivated by the symmetries of the model. Shifting the right-handed neutrinos and charged leptons slightly from the fixed point provides a new mechanism for understanding the absence of relations of the type $m_e=m_u$ or $m_e=m_d$ in Quark-Lepton symmetric models. Flavour changing neutral currents resulting from Kaluza Klein gluon exchange, which typically arise in the quark sector of split fermion models, are suppressed due to the localisation of quarks at one point. The separation of quarks and leptons in the compact extra dimension also acts to suppress the proton decay rate. This permits the extra dimension to be much larger than that obtained in a previous construct, with the bound $1/R\gtrsim30$ TeV obtained.Comment: 12 pages, references added to match published versio

Health Savings Account - Eligible High Deductible Health Plans: Updating the Definition of Prevention

High-deductible health plans (HDHPs) are an important and growing part of the health insurance landscape. By some estimates, as many as 80 percent of large employers may offer an HDHP in 2014. In 2013, more than 15 million Americans received health coverage through an HDHP, a more than a threefold increase since 2007.As outlined by the U.S. Treasury Department, individuals with an HSA-eligible HDHP are required to pay the full cost of most medications and services -- in theory utilizing pre-tax HSA funds -- until deductibles are met. However, the 2003 authorizing legislation and further guidance include a safe harbor allowing plans to cover primary preventive services, those typically deemed to prevent the onset of disease, before the deductible is satisfied.Services or benefits meant to treat "an existing illness, injury or condition," are excluded from first-dollar coverage in HSA-eligible HDHPs, which encompasses most secondary preventive services. For example, plans are prohibited from providing first dollar coverage of disease management services such as insulin, eye and foot exams, and glucose monitoring supplies for patients with diabetes.As chronic disease conditions currently make up 75 percent of total U.S. health spending, appropriate chronic disease management is an important tool to lower long-term health care costs. As the market for HDHPs grow, it is important that they maintain the flexibility to allow for effective health management of all beneficiaries. This report addresses the strict definition of prevention that an HDHP must follow for it to include a pre-tax health savings account (HSA), and how this restriction limits the effectiveness of current plans. A potential solution - allowing HSA-eligible HDHPs to provide first-dollar coverage for targeted, evidence-based, secondary preventive services that prevent chronic disease progression and related complications - can improve patient-centered outcomes, add efficiency to medical spending, and enhance HDHP attractiveness.A multi-disciplinary research team from the University of Michigan's Center for Value-Based Insurance Design, Harvard Medical School, and the University of Minnesota conducted a multi-part project to investigate the impact of updatingthe definition of prevention for HDHPs to include selected secondary preventive services that are frequently used as health plan quality metrics and included as elements of pay-for-performance programs. Specifically, the project aimed to: 1) determine the premium effect, actuarial value, and estimated market uptake of the novel HDHP plan that covers these evidence-based services outside the deductible, and 2) explore through interviews whether insurance industry experts found coverage of secondary preventive services a worthwhile endeavor

Three new infrared bands of the He-OCS complex

Three new infrared bands of the weakly-bound He-OCS complex are studied, using tunable lasers to probe a pulsed supersonic slit jet expansion. They correspond to the (0400) <-- (0000), (1001)<-- (0000), and (0401) <-- (0000) transitions of OCS at 2105, 2918, and 2937 cm-1, respectively. The latter band is about 7900 times weaker than the previously studied OCS nu1 fundamental. Vibrational shifts relative to the free OCS monomer are found to be additive. Since carbonyl sulfide has previously been shown to be a valuable probe of superfluid quantum solvation effects in helium clusters and droplets, the present results could be useful for future studies of vibrational effects in such systems.Comment: 16 pages, 1 figure, 4 table