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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Observation of a Resonant Structure in e + e − → K + K − π 0 π 0
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Dark Matter Signals from Timing Spectra at Neutrino Experiments
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First Observation of D + → η μ + ν μ and Measurement of Its Decay Dynamics
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Determination of Strong-Phase Parameters in D → K S , L 0 π + π −
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Measurements of Absolute Branching Fractions of Fourteen Exclusive Hadronic D Decays to η
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Study of Open-Charm Decays and Radiative Transitions of the X (3872)
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Free Space Ramsey Spectroscopy in Rubidium with Noise below the Quantum Projection Limit
In this work, we demonstrate the utility of optical cavity generated spin-squeezed states in free space atomic fountain clocks in ensembles of 390 000 87 Rb atoms. Fluorescence imaging, correlated to an initial quantum nondemolition measurement, is used for population spectroscopy after the atoms are released from a confining lattice. For a free fall time of 4 milliseconds, we resolve a single-shot phase sensitivity of 814(61) microradians, which is 5.8(0.6) decibels (dB) below the quantum projection limit. We observe that this squeezing is preserved as the cloud expands to a roughly 200 μ m radius and falls roughly 300 μm in free space. Ramsey spectroscopy with 240 000 atoms at a 3.6 ms Ramsey time results in a single-shot fractional frequency stability of 8.4(0.2) × 10 –12 , 3.8(0.2) dB below the quantum projection limit. The sensitivity and stability are limited by the technical noise in the fluorescence detection protocol and the microwave system, respectively.
Σ + and Σ ¯ − Polarization in the J / ψ and ψ ( 3686 ) Decays
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Efficient Ground-State Cooling of Large Trapped-Ion Chains with an Electromagnetically-Induced-Transparency Tripod Scheme
Here, we report the electromagnetically-induced-transparency (EIT) cooling of a large trapped 171 Yb + ion chain to the quantum ground state. Unlike conventional EIT cooling, we engage a four-level tripod structure and achieve fast sub-Doppler cooling over all motional modes. We observe simultaneous ground-state cooling across the complete transverse mode spectrum of up to 40 ions, occupying a bandwidth of over 3 MHz. The cooling time is observed to be less than 300 μ s , independent of the number of ions. Such efficient cooling across the entire spectrum is essential for high-fidelity quantum operations using trapped ion crystals for quantum simulators or quantum computers.
Inverse Primakoff Scattering as a Probe of Solar Axions at Liquid Xenon Direct Detection Experiments
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Standard-Model Prediction of ε K with Manifest Quark-Mixing Unitarity
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Lattice QCD Calculations of Transverse-Momentum-Dependent Soft Function through Large-Momentum Effective Theory
The transverse-momentum-dependent (TMD) soft function is a key ingredient in QCD factorization of Drell-Yan and other processes with relatively small transverse momentum. We present a lattice QCD study of this function at moderately large rapidity on a 2 + 1 flavor CLS dynamic ensemble with a = 0.098 fm. We extract the rapidity-independent (or intrinsic) part of the soft function through a large-momentumtransfer pseudoscalar meson form factor and its quasi-TMD wave function using leading-order factorization in large-momentum effective theory. We also investigate the rapidity-dependent part of the soft function—the Collins-Soper evolution kernel—based on the large-momentum evolution of the quasi-TMD wave function.
Flavor Decomposition for the Proton Helicity Parton Distribution Functions
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Nondissipative Second-Order Transport, Spin, and Pseudogauge Transformations in Hydrodynamics
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Branching Fraction Measurements of the Rare B s 0 → ϕ μ + μ − and B s 0 → f 2 ′ ( 1525 ) μ + μ − Decays
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