Stabilizing All Geometric Moduli in Heterotic Calabi-Yau Vacua

We propose a scenario to stabilize all geometric moduli - that is, the complex structure, Kahler moduli and the dilaton - in smooth heterotic Calabi-Yau compactifications without Neveu-Schwarz three-form flux. This is accomplished using the gauge bundle required in any heterotic compactification, whose perturbative effects on the moduli are combined with non-perturbative corrections. We argue that, for appropriate gauge bundles, all complex structure and a large number of other moduli can be perturbatively stabilized - in the most restrictive case, leaving only one combination of Kahler moduli and the dilaton as a flat direction. At this stage, the remaining moduli space consists of Minkowski vacua. That is, the perturbative superpotential vanishes in the vacuum without the necessity to fine-tune flux. Finally, we incorporate non-perturbative effects such as gaugino condensation and/or instantons. These are strongly constrained by the anomalous U(1) symmetries which arise from the required bundle constructions. We present a specific example, with a consistent choice of non-perturbative effects, where all remaining flat directions are stabilized in an AdS vacuum.Comment: 24 pages, 2 figure

Who performs neonatal hip assessment:is there a cause for concern?

Objective The UK falls behind other European countries in the early detection of developmental dysplasia of the hip (DDH) and screening strategies differ for early detection. Clinical detection of DDH is challenging and recognised to be dependent on examiner experience. No studies exist assessing the number of personnel currently involved in such assessments. Our objective was to review the current screening procedure by studying a cohort of newborn babies in one teaching hospital and assess the number of health professionals involved in neonatal hip assessment and the number of examinations undertaken during one period by each individual. Methods This was a retrospective observational study assessing all babies born consecutively over a 14-week period in 2020. Record of each initial baby check was obtained from BadgerNet. Follow-up data on ultrasound or orthopaedic outpatient referrals were obtained from clinical records. Results 1037 babies were examined by 65 individual examiners representing 9 different healthcare professional groups. The range of examinations conducted per examiner was 1–97 with a median of 5.5 examinations per person. 49% of individuals examined 5 or less babies across the 14 weeks, with 18% only performing 1 examination. Of the six babies (0.48%) treated for DDH, one was picked up on neonatal assessment. Conclusion In a system where so many examiners are involved in neonatal hip assessment, the experience is limited for most examiners. Currently high rates of late presentation of DDH are observed locally, which are in accordance with published national experience. The potential association merits further investigation.</p

The Integrated Mental Health Atlas of Western Sydney

Australians living with serious and continuing ill-health face bewilderingly complex health and social care systems. Even experienced health professionals have trouble navigating this health care maze. The mental health service system poses some of the greatest navigation challenges. The recovery of individuals living with mental health issues, requires a smooth link between acute and domiciliary health care, housing and other social care agencies. The need for simple rules of navigation is strong, but fragmentation and gaps in services remain great, confounding attempts to understand and organise appropriate care and support. The need for deeper knowledge about the mental health system in Western Sydney motivated Western Sydney Partners in Recovery to fund the development of the Integrated Mental Health Atlas of Western Sydney. The aim of this Atlas is twofold; 1) to help providers and consumers to navigate the system, by improving their knowledge about the services available in the area; and 2) as a tool for evidence-informed planning, as it presents a critical analysis of the pattern of mental health care provided within the boundaries of Western Sydney Local Health District

The essential value of long-term experimental data for hydrology and water management

We would like to thank the European Research Council ERC for funding the VeWa project and most of Tetzlaff's time (project GA 335910 VeWa). No data were used in producing this manuscript.Peer reviewedPublisher PD

The electron accelerator for the AWAKE experiment at CERN

The AWAKE collaboration prepares a proton driven plasma wakefield acceleration experiment using the SPS beam at CERN. A long proton bunch extracted from the SPS interacts with a high power laser and a 10 m long rubidium vapour plasma cell to create strong wakefields allowing sustained electron acceleration. The electron bunch to probe these wakefields is supplied by a 20 MeV electron accelerator. The electron accelerator consists of an RF-gun and a short booster structure. This electron source should provide beams with intensities between 0.1 and 1 nC, bunch lengths between 0.3 and 3 ps and an emittance of the order of 2 mm mrad. The wide range of parameters should cope with the uncertainties and future prospects of the planned experiments. The layout of the electron accelerator, its instrumentation and beam dynamics simulations are presented

Interface electronic states and boundary conditions for envelope functions

The envelope-function method with generalized boundary conditions is applied to the description of localized and resonant interface states. A complete set of phenomenological conditions which restrict the form of connection rules for envelope functions is derived using the Hermiticity and symmetry requirements. Empirical coefficients in the connection rules play role of material parameters which characterize an internal structure of every particular heterointerface. As an illustration we present the derivation of the most general connection rules for the one-band effective mass and 4-band Kane models. The conditions for the existence of Tamm-like localized interface states are established. It is shown that a nontrivial form of the connection rules can also result in the formation of resonant states. The most transparent manifestation of such states is the resonant tunneling through a single-barrier heterostructure.Comment: RevTeX4, 11 pages, 5 eps figures, submitted to Phys.Rev.

Sequencing of sporadic Attention‐Deficit Hyperactivity Disorder (ADHD) identifies novel and potentially pathogenic de novo variants and excludes overlap with genes associated with autism spectrum disorder

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137575/1/ajmgb32527.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137575/2/ajmgb32527_am.pd

Stabilizing the Complex Structure in Heterotic Calabi-Yau Vacua

In this paper, we show that the presence of gauge fields in heterotic Calabi-Yau compacitifications causes the stabilisation of some, or all, of the complex structure moduli of the Calabi-Yau manifold while maintaining a Minkowski vacuum. Certain deformations of the Calabi-Yau complex structure, with all other moduli held fixed, can lead to the gauge bundle becoming non-holomorphic and, hence, non-supersymmetric. This leads to an F-term potential which stabilizes the corresponding complex structure moduli. We use 10- and 4-dimensional field theory arguments as well as a derivation based purely on algebraic geometry to show that this picture is indeed correct. An explicit example is presented in which a large subset of complex structure moduli is fixed. We demonstrate that this type of theory can serve as the hidden sector in heterotic vacua and can co-exist with realistic particle physics.Comment: 17 pages, Late