The Proposed High Energy Telescope (HET) for EXIST

The hard X-ray sky now being studied by INTEGRAL and Swift and soon by NuSTAR is rich with energetic phenomena and highly variable non-thermal phenomena on a broad range of timescales. The High Energy Telescope (HET) on the proposed Energetic X-ray Imaging Survey Telescope (EXIST) mission will repeatedly survey the full sky for rare and luminous hard X-ray phenomena at unprecedented sensitivities. It will detect and localize (<20", at 5 sigma threshold) X-ray sources quickly for immediate followup identification by two other onboard telescopes - the Soft X-ray imager (SXI) and Optical/Infrared Telescope (IRT). The large array (4.5 m^2) of imaging (0.6 mm pixel) CZT detectors in the HET, a coded-aperture telescope, will provide unprecedented high sensitivity (~0.06 mCrab Full Sky in a 2 year continuous scanning survey) in the 5 - 600 keV band. The large field of view (90 deg x 70 deg) and zenith scanning with alternating-orbital nodding motion planned for the first 2 years of the mission will enable nearly continuous monitoring of the full sky. A 3y followup pointed mission phase provides deep UV-Optical-IR-Soft X-ray and Hard X-ray imaging and spectroscopy for thousands of sources discovered in the Survey. We review the HET design concept and report the recent progress of the CZT detector development, which is underway through a series of balloon-borne wide-field hard X-ray telescope experiments, ProtoEXIST. We carried out a successful flight of the first generation of fine pixel large area CZT detectors (ProtoEXIST1) on Oct 9, 2009. We also summarize our future plan (ProtoEXIST2 & 3) for the technology development needed for the HET.Comment: 10 pages, 13 figures, 2 tables, SPIE Conference "Astronomical Telescopes and Instrumentation 2010"; to appear in Proceedings SPIE (2010

Control surface wettability with nanoparticles from phase-change materials

The wetting state of surfaces can be controlled physically from the highly hydrophobic to hydrophilic states using the amorphous-to-crystalline phase transition of Ge2Sb2Te5 (GST) nanoparticles as surfactant. Indeed, contact angle measurements show that by increasing the surface coverage of the amorphous nanoparticles the contact angle increases to high values ∼140°, close to the superhydrophobic limit. However, for crystallized nanoparticle assemblies after thermal annealing, the contact angle decreases down to ∼40° (significantly lower than that of the bare substrate) leading to an increased hydrophilicity. Moreover, the wettability changes are also manifested on the capillary adhesion forces by being stronger for the crystallized GST state

Parity transitions in the superconducting ground state of hybrid InSb-Al Coulomb islands

The number of electrons in small metallic or semiconducting islands is quantized. When tunnelling is enabled via opaque barriers this number can change by an integer. In superconductors the addition is in units of two electron charges (2e), reflecting that the Cooper pair condensate must have an even parity. This ground state (GS) is foundational for all superconducting qubit devices. Here, we study a hybrid superconducting-semiconducting island and find three typical GS evolutions in a parallel magnetic field: a robust 2e-periodic even-parity GS, a transition to a 2e-periodic odd-parity GS,and a transition from a 2e- to a 1e-periodic GS. The 2e-periodic odd-parity GS persistent in gate-voltage occurs when a spin-resolved subgap state crosses zero energy. For our 1e-periodic GSs we explicitly show the origin being a single zero-energy state gapped from the continuum, i.e. compatible with an Andreev bound states stabilized at zero energy or the presence of Majorana zero modes

Empathic accuracy and oxytocin after tryptophan depletion in adults at risk for depression

Contains fulltext : 172451.pdf (Publisher’s version ) (Open Access

Quantized Majorana conductance

Majorana zero-modes hold great promise for topological quantum computing. Tunnelling spectroscopy in electrical transport is the primary tool to identify the presence of Majorana zero-modes, for instance as a zero-bias peak (ZBP) in differential-conductance. The Majorana ZBP-height is predicted to be quantized at the universal conductance value of 2e2/h at zero temperature. Interestingly, this quantization is a direct consequence of the famous Majorana symmetry, 'particle equals antiparticle'. The Majorana symmetry protects the quantization against disorder, interactions, and variations in the tunnel coupling. Previous experiments, however, have shown ZBPs much smaller than 2e2/h, with a recent observation of a peak-height close to 2e2/h. Here, we report a quantized conductance plateau at 2e2/h in the zero-bias conductance measured in InSb semiconductor nanowires covered with an Al superconducting shell. Our ZBP-height remains constant despite changing parameters such as the magnetic field and tunnel coupling, i.e. a quantized conductance plateau. We distinguish this quantized Majorana peak from possible non-Majorana origins, by investigating its robustness on electric and magnetic fields as well as its temperature dependence. The observation of a quantized conductance plateau strongly supports the existence of non-Abelian Majorana zero-modes in the system, consequently paving the way for future braiding experiments.Comment: 5 figure

Daily life stress and the cortisol awakening response : testing the anticipation hypothesis

Acknowledgments We thank Paul Stewart for his contribution to data collection and Dr Matthew Jones for programming the handheld computers. Author Contributions Conceived and designed the experiments: WS DJP. Performed the experiments: DJP. Analyzed the data: WS. Wrote the paper: WS DJP.Peer reviewedPublisher PD

Electric field tunable superconductor-semiconductor coupling in Majorana nanowires

We study the effect of external electric fields on superconductor-semiconductor coupling by measuring the electron transport in InSb semiconductor nanowires coupled to an epitaxially grown Al superconductor. We find that the gate voltage induced electric fields can greatly modify the coupling strength, which has consequences for the proximity induced superconducting gap, effective g-factor, and spin-orbit coupling, which all play a key role in understanding Majorana physics. We further show that level repulsion due to spin-orbit coupling in a finite size system can lead to seemingly stable zero bias conductance peaks, which mimic the behavior of Majorana zero modes. Our results improve the understanding of realistic Majorana nanowire systems.Comment: 10 pages, 5 figures, supplemental information as ancillary fil

Measuring empathy in schizophrenia:The Empathic Accuracy Task and its correlation with other empathy measures

Introduction: Empathy is an interpersonal process impaired in schizophrenia. Past studies have mainly used questionnaires or performance-based tasks with static cues to measure cognitive and affective empathy. We used the Empathic Accuracy Task (EAT) designed to capture dynamic aspects of empathy by using videoclips in which perceivers continuously judge emotionally charged stories. We compared individuals with schizophrenia with a healthy comparison group and assessed correlations among EAT and three other commonly used empathy measures. Method: Patients (n = 92) and a healthy comparison group (n = 42) matched for age, gender and education completed the EAT, the Interpersonal Reactivity Index, Questionnaire of Cognitive and Affective Empathy and Faux Pas. Differences between groups were analyzed and correlations were calculated between empathy measurement instruments. Results: The groups differed in EAT performance, with the comparison group outperforming patients. A moderating effect was found for emotional expressivity of the target: while both patients and the comparison group scored low when judging targets with low expressivity, the comparison group performed better than patients with more expressive targets. Though there were also group differences on the empathy questionnaires, EAT performance did not correlate with questionnaire scores. Conclusions: Individuals with schizophrenia benefit less from the emotional expressivity of other people than the comparison group, which contributes to their impaired empathic accuracy. The lack of correlation between the EAT and the questionnaires suggests a distinction between self-report empathy and actual empathy performance. To explore empathic difficulties in real life, it is important to use instruments that take the interpersonal perspective into account. (C) 2019 Published by Elsevier B.V

A first Alps - dedicated gravity data set - introduction and status of the AlpArray gravity field activities

In this contribution, activities of the AlpArray Gravity Research Group (AAGRG) are introduced. Since 2018, this group in the frame of the AlpArray project (http://www.alparray.ethz.ch/en/home/) prepares gravity and other data sets to support multidisciplinary goals of the project. It is focused on the mantle, plate and surface processes in the Alps-Apennines-Carpathians-Dinarides orogenic system. In 2018, the AAGRG set up its own methodology guidelines and assembled available land-gravity data and digital elevation model (DEM) data from all the participating countries. Our presentation targets especially three goals: 1) to introduce AAGRG activities as an integral part of the AlpArray project for studying Alpine orogeny \u2013 a goal that by definition requires international cooperation, 2) to review the input data and the works accomplished so far, and, 3) to discuss the steps to be taken to produce detailed gravity maps of the region \u2013 the first Alps-dedicated gravity field data set. We plan to prepare gravity grids in a homogeneous processing approach of either 2x2 km or 4x4 km resolution, depending on the coverage and data quality. The final data sets will be made public in late 2019. A special emphasis is put on the calculation of the Bouguer anomaly using ellipsoidal rather tha normal heights. For calculating topographic effects the preference is given to local DEMs, where available, as they often provide higher quality and spatial resolutions. The public gravity data sets are evaluated with the high-resolution geopotential models like EIGEN-6C4 or EGM2008 \u2013 a useful means for identifying biases in the data coming from various countries and campaigns