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Amplitude modes in three-dimensional spin dimers away from quantum critical point
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Generation of highly mutually coherent hard-x-ray pulse pairs with an amplitude-splitting delay line
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Toward coherent quantum computation of scattering amplitudes with a measurement-based photonic quantum processor
In recent years, applications of quantum simulation have been developed to study the properties of strongly interacting theories. This has been driven by two factors: on the one hand, needs from theorists to have access to physical observables that are prohibitively difficult to study using classical computing; on the other hand, quantum hardware becoming increasingly reliable and scalable to larger systems. In this work, we discuss the feasibility of using quantum optical simulation for studying scattering observables that are presently inaccessible via lattice QCD and are at the core of the experimental program at Jefferson Laboratory, the future Electron-Ion Collider, and other accelerator facilities. We show that recent progress in measurement-based photonic quantum computing can be leveraged to provide deterministic generation of required exotic gates and implementation in a single photonic quantum processor. Published by the American Physical Society 2024
Robust Two-Qubit Geometric Phase Gates using Amplitude and Frequency Ramping
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Statistical Behavior of Low-Amplitude Power System Point-on-Wave Measurements
The power grid is undergoing massive changes to ensure resiliency and reliability in a more decentralized world. Distributed energy resources are becoming a prominent source of generation, potentially leading to a lack of centralized generation sources. Due to these new behaviors and system topologies, it is important to install measurement devices that are 1) accurate and 2) self-aware of their measurement quality. In this paper, a residential-scale microgrid is used to generate voltage and current waveforms, captured by Verivolt and National Instruments measurement equipment. A least-squares approach is used to separate the “clean” signals from the noise. Finally, Gaussian mixture modeling is used to approximate noise distributions, and it is shown these higher-order distribution estimates are a better fit to voltage and current noise profiles than single-mode Gaussian estimates.
SU-C-210-01: Are Clinically Relevant Dosimetric Endpoints Significantly Better with Gating of Lung SBRT Vs. ITV-Based Treatment?: Results of a Large Cohort Investigation Analyzing Predictive Dosimetric Indicators as a Function of Tumor Volume and Motion Amplitude
Purpose: To quantitatively compare patient internal target volume (ITV)-based plans with retrospectively generated gated plans to evaluate potential dosimetric improvements in lung toxicity from gated radiotherapy. Methods: Evaluation was conducted for 150 stereotactic body radiation therapy (SBRT) treatment plans for 128 early-stage (T1–T3, <5cm) NSCLC patients. PTV margins were: ITV+5 mm (ITV-plan) and GTV+5 mm (Gated-plan). ITV-based and gated treatment plans were compared on the same free-breathing CT. ITV-based plan constraints were used to re-optimize and recalculate new gated plans. Plans were generated for 3 fractionation regimens: 3×18Gy, 4×12Gy (original), and 5×10Gy. Physical dose was converted to equivalent dose in 2Gy fractions (EQD2), which was used to determine mean lung dose (MLD) and percent volume of lung receiving ≥20Gy (V20). MLD and V20 differences between gating and ITV-based plans were analyzed as a function of both three-dimensional (3D) motion and tumor volume. The low dose region, V5, was also evaluated. Results: MLD and V20 differences between gated and ITV-based plans were larger for lower (1.48±1.32Gy and 1.44±1.29%) than for upper lobe tumors (0.89±0.74Gy and 0.92±0.71%) due to smaller tumor motion (2.9±3.4mm) compared to lower lobe tumors (8.1±6.1mm). Average differences of <1–2% were noted in V5 between ITV and gated plans. Dosimetric differences between gating and ITV-based methods increased with increasing tumor motion and decreasing tumor volume. Overall, average MLD (8.04±3.92Gy) and V20 (8.29±4.33%) values for ITV-based plans were already well below clinical guidelines, even for the 3×18Gy dose scheme, for which largest differences were noted relative to gated plans. Similar results were obtained for 5×10Gy and 4×12Gy regimens. Conclusion: Clinically relevant improvement in pulmonary toxicity, based on predictors of radiation pneumonitis (MLD and V20) was not generally observed, though improvement for tumors with 3D motion >15 mm, mainly concentrated in peripheral lower lobe tumors, may be considered clinically relevant. Work supported in part by a grant from Varian Medical systems, Palo Alto, CA.
SU-F-J-139: Amplitude of Low Frequency Fluctuation(ALFF) and Regional Homogeneity (ReHo) Study of the Respiration Motion Control Byhypnosis
Purpose: Respiration control by hypnosis is a method in reducing the detriment to the healthy organs or organizations for patients during radiotherapy, especially for lung and abdomen cancer (Fig.1). It’s hypothesized that there exists alterations neurological brain activity during the hypnosis state of respiratory motion control in comparison with resting state. Methods: Thirteen healthy volunteers were organized to participate in a hypnosis experiment that consisted of two sectional scans of functional magnetic resonance imaging (fMRI), rest state condition (RSC) scanning and hypnosis state condition (HSC) scanning. In addition, the coronal section of the lung was scanned during both conditions. During the hypnosis scan, the volunteers were under the hypnotists’ guidance to keep peace and stable respiration. To evaluate the altered physiological performance of hypnosis in the respiratory control, three conventional indicators ALFF/fALFF (0.01–0.08Hz) and ReHo, were applied to identify the difference. Results: Compared with RSC, HSC showed significant (p<0.05) higher ReHo in superior temporal gyrus, middle temporal gyrus, frontal lobe, middle occipital gyrus, parietal lobe, cerebellum anterior Lobe and lingual gyrus, and left brainstem (Fig.2). While significant lower ReHo in middle frontal gyrus, superior frontal gyrus, inferior semi-lunar lobule, sub-lobar and limbic lobe (Fig.2). As for the ALFF results, significant higher value of HSC was observed in superior temporal gyrus, middle temporal gyrus, middle occipital gyrus, middle occipital gyrus, cerebellum anterior lobe, lingual gyrus, sub-lobar, limbic lobe, and lower in cerebellum posterior lobe, inferior semi-lunar lobule, inferior parietal lobule right middle frontal gyrus, cerebellar tonsil (Fig.3). The results of fALFF were similar to ALFF (Fig.4). The above results demonstrated that most significant regions of brain were uniform between ReHo and ALFF/fALFF. Conclusion: Hypnosis is a new psychological and helpful technology for respiration control. This study provides new insights of neurological brain activity during hypnosis of respiration control. This work is supported by grants from Guangdong Innovative Research Team Program of China (Grant No. 2011S013), National 863 Programs of China (Grant Nos. 2012AA02A604 and 2015AA043203), the National High-tech R&D Program for Young Scientists by the Ministry of Science and Technology of China (Grant No. 2015AA020917)
Large-amplitude nuclear motion formulated in terms of dissipation of quantum fluctuations
The potential-barrier penetrability and quasi-stationary thermal-decay rate of a metastable state are formulated in terms of microscopic quantum diffusion. Apart from linear coupling in momentum between the collective and internal subsystems, the formalism embraces the more general case of linear couplings in both the momentum and the coordinates. The developed formalism is then used for describing the process of projectile-nucleus capture by a target nucleus at incident energies near and below the Coulomb barrier. The capture partial probability, which determines the cross section for formation of a dinuclear system, is derived in analytical form. The total and partial capture cross sections, mean and root-mean-square angular momenta of the formed dinuclear system, astrophysical -factors, logarithmic derivatives, and barrier distributions are derived for various reactions. Also investigated are the effects of nuclear static deformation and neutron transfer between the interacting nuclei on the capture cross section and its isotopic dependence, and the entrance-channel effects on the capture process. The results of calculations for reactions involving both spherical and deformed nuclei are in good agreement with available experimental data.
Contribution of the excited 1{sup +} states of {sup 100}Tc to the 2ν2β-amplitude of {sup 100}Mo
The total and differential intensities of the two-neutrino double beta transition in {sup 100}Mo are calculated by taking into account experimental data on the charge-exchange reactions on {sup 100}Mo. It is shown that excited 1{sup +} states should be considered in addition to the ground state of the intermediate nucleus {sup 100}Tc, which leads to the generalization of the SSD mechanism for the two-neutrino process.
Examining the time dependence of DAMA’s modulation amplitude
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Phenomenology of relativistic $$\mathbf {3}\rightarrow \mathbf {3}$$ reaction amplitudes within the isobar approximation
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Resonance in Fast-Wave Amplitude in the Periphery of Cylindrical Plasmas and Application to Edge Losses of Wave Heating Power in Tokamaks
Heating magnetically confined plasmas using waves in the ion-cyclotron range of frequencies typically requires coupling these waves over a steep density gradient. This process has produced an unexpected and deleterious phenomenon on the National Spherical Torus eXperiment (NSTX): a prompt loss of wave power along magnetic field lines in front of the antenna to the divertor. Understanding this loss may be key to achieving effective heating and expanding the operational space of NSTX-Upgrade. Here, we propose that a new type of mode, which conducts a significant fraction of the total wave power in the low-density peripheral plasma, is driving these losses. We demonstrate the existence of such modes, which are distinct from surface modes and coaxial modes, in a cylindrical cold-plasma model when a half wavelength structure fits into the region outside the core plasma. The latter condition generalizes the previous hypothesis regarding the occurence of the edge losses and may explain why full-wave simulations predict these losses in some cases but not others. If valid, this condition implies that outer gap control is a potential strategy for mitigating the losses in NSTX-Upgrade in addition to raising the magnetic field or influencing the edge density.
Benchmarking Simulated Precipitation Variability Amplitude across Time Scales
Here, objective performance metrics that measure precipitation variability across time scales from subdaily to interannual are presented and applied to Historical simulations of Coupled Model Intercomparison Project phase 5 and 6 (CMIP5 and CMIP6) models. Three satellite-based precipitation estimates (IMERG, TRMM, and CMORPH) are used as reference data. We apply two independent methods to estimate temporal variability of precipitation and compare the consistency in their results. The first method is derived from power spectra analysis of 3-hourly precipitation, measuring forced variability by solar insolation (diurnal and annual cycles) and internal variability at different time scales (subdaily, synoptic, subseasonal, seasonal, and interannual). The second method is based on time averaging and facilitates estimating the seasonality of subdaily variability. Supporting the robustness of our metric, we find a near equivalence between the results obtained from the two methods when examining simulated-to-observed ratios over large domains (global, tropics, extratropics, land, or ocean). Additionally, we demonstrate that our model evaluation is not very sensitive to the discrepancies between observations. Our results reveal that CMIP5 and CMIP6 models in general overestimate the forced variability while they underestimate the internal variability, especially in the tropical ocean and higher-frequency variability. The underestimation of subdaily variability is consistent across different seasons. The internal variability is overall improved in CMIP6, but remains underestimated, and there is little evidence of improvement in forced variability. Increased horizontal resolution results in some improvement of internal variability at subdaily and synoptic time scales, but not at longer time scales.
Ultrahigh extinction on-chip amplitude modulators with broadband operation.
Abstract not provided.