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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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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Search for heavy neutral leptons in final states with electrons, muons, and hadronically decaying tau leptons in proton-proton collisions at $ \sqrt{s} $ = 13 TeV

A search for heavy neutral leptons (HNLs) of Majorana or Dirac type using proton-proton collision data at $ \sqrt{s} $ = 13 TeV is presented. The data were collected by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 138 fb$^{−1}$. Events with three charged leptons (electrons, muons, and hadronically decaying tau leptons) are selected, corresponding to HNL production in association with a charged lepton and decay of the HNL to two charged leptons and a standard model (SM) neutrino. The search is performed for HNL masses between 10 GeV and 1.5 TeV. No evidence for an HNL signal is observed in data. Upper limits at 95% confidence level are found for the squared coupling strength of the HNL to SM neutrinos, considering exclusive coupling of the HNL to a single SM neutrino generation, for both Majorana and Dirac HNLs. The limits exceed previously achieved experimental constraints for a wide range of HNL masses, and the limits on tau neutrino coupling scenarios with HNL masses above the W boson mass are presented for the first time.[graphic not available: see fulltext]

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1989

C-O-H ratios of silicate melt inclusions in basalts from the Galapagos Spreading Center near 95 deg W - A laser decrepitation mass spectrometry study

Ratios of C, O, and H dissolved in silicate glass inclusions and pillow rind glasses in samples from the Galapagos Spreading Center near 95 deg W were analyzed (using laser volatilization and mass spectrometry), and the data were assessed in terms of mantle source compositions, oxygen fugacity, kinetic fractionation, and magmatic degassing. It was found that glass inclusions in the Galapagos failing rift lavas are higher and more variable in CO2/H2O (about 0.641) relative to inclusions in propagating rift lavas (about 0.245). This difference is considered to reflect different degrees of degassing during contrasting magmatic histories of the two regions.

Yonover, Robert N.↗
DOE OSTI2024

Limits on W R from Meson Decays

In this Letter we show that pseudoscalar meson leptonic decay data can be used to set stringent limits on the mass $m$ W$_{R}$ of a right-handed vector boson, such as the one that appears in left-right symmetric models. We have shown that for a heavy neutrino with a mass $m_N$ in the range 50 < $m_N$/MeV < 1900 one can constraint $m$ W$_{R}$ ≳ (4–19) TeV at 90% CL. This provides the most stringent experimental limits on the $W_R$ mass to date for this heavy neutrino mass range.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS2018

Orifice Mass Flow Calculation in NASA's W-8 Single Stage Axial Compressor Facility

Updates to the orifice mass flow calculation for the W-8 Single Stage Axial Compressor Facility at NASA Glenn Research Center are provided to include the effect of humidity and incorporate ISO 5167. A methodology for including the effect of humidity into the inlet orifice mass flow calculation is provided. Orifice mass flow calculations provided by ASME PTC-19.5-2004, ASME MFC-3M-2004, ASME Fluid Meters, and ISO 5167 are compared for W-8's atmospheric inlet orifice plate. Differences in expansion factor and discharge coefficient given by these standards give a variation of about +/- 75% mass flow except for a few cases. A comparison of the calculations with an inlet static pressure mass flow correlation and a fan exit mass flow integration using test data from a 2017 turbofan rotor test in W-8 show good agreement between the inlet static pressure mass flow correlation, ISO 5167, and ASME Fluid Meters. While W-8's atmospheric inlet orifice plate violates the pipe diameter limit defined by each of the standards, the ISO 5167 is chosen to be the primary orifice mass flow calculation to use in the W-8 facility.

Aerodynamics↗
NASA NTRS1989

C-O-H ratios of silicate melt inclusions in basalts from the Galapagos Spreading Center near 95 degrees W: a laser decrepitation mass spectrometry study

Volatile ratios (primarily of H2O and CO2) in individual silicate melt (glass) inclusions in minerals have been analyzed using laser volatilization and mass spectrometry. A Nd-glass laser was used to produce 50-micrometer diameter pits in silicate melt inclusions. Released volatiles were analyzed directly with a computer-controlled quadrupole mass spectrometer. The detection limits for CO2 and H2O were on the order of 3 x 10(-14) and 3 x 10(-13) moles, respectively. The reproducibility for CO2/H2O was better than +/- 9%. The total range of volatile ratios from vitreous silicate glass inclusions contained in a suite of Galapagos lavas were: 0.018 to 1.193 for CO2/H2O; 0.002 to 0.758 for CO/H2O; 0 to 0.454 for CH4/H2O; and 0 to 0.432 for Ar/H2O. The mean CO2/H2O from the propagating rift (0.245 +/- 0.068) silicate glass inclusions is significantly lower than that of the actively failing rift (0.641 +/- 0.241); this difference probably reflects different degrees of degassing during magmatic histories for the two regions. Relatively undifferentiated failing rift magmas must have relatively short crustal residence times prior to eruption and, therefore, have not undergone significant degassing of CO2, as would appear to be the case for the more highly fractionated propagating rift magmas. The laser-mass spectrometric system described herein has the ability to act as a point-source probing device that can differentiate between the various volatile sites in minerals and rocks (as well as synthetic materials) on a micrometer scale.

NASA Discipline Exobiology↗
NASA NTRS1972

Measurement of the neutral composition of the lower thermosphere above Fort Churchill by rocket-borne mass spectrometer.

Measurement of the neutral atmospheric composition above Fort Churchill, Canada (59 N, 94 W), by mass spectrometers in two rocket flights at 0835 CST on Feb. 4 and 6, 1969. A quantitative measure for the extent of agreement with static diffusive equilibrium is introduced, and substantial agreement with profiles predicted when static diffusive equilibrium was assumed is found for all constituents including helium. A sensitive search for atomic nitrogen yielded upper limits of a few per cent for one flight and of 0.2% for the other.

Hickman, D. R.↗
DOE OSTI2024

Nuclear suppression of coherent J / ψ photoproduction in heavy-ion ultraperipheral collisions and leading twist nuclear shadowing

We determine the nuclear suppression factor S Pb ( x ) , where x = M J / ψ 2 / W γ p 2 with M J / ψ the J / ψ mass and W γ p the photon-nucleon energy, for the cross section of coherent J / ψ photoproduction in heavy-ion ultraperipheral collisions at the Large Hadron Collider and Relativistic Heavy Ion Collider by performing the χ 2 fit to all available data on the cross section d σ A A → J / ψ A A / d y as a function of the J / ψ rapidity y and the photoproduction cross section σ γ A → J / ψ A ( W γ p ) as a function of W γ p . We find that while the d σ A A → J / ψ A A / d y data alone constrain S Pb ( x ) for x ≥ 10 − 3 , the combined d σ A A → J / ψ A A / d y and σ γ A → J / ψ A ( W γ p ) data allow us to determine S Pb ( x ) in the wide interval 10 − 5 < x < 0.05 . In particular, the data favor S Pb ( x ) , which decreases with a decrease of x in the 10 − 4 < x < 0.01 interval and can be both decreasing or constant for x < 10 − 4 . Identifying S Pb ( x ) with the ratio of the gluon distributions in Pb and the proton R g ( x , Q 0 2 ) = g A ( x , Q 0 2 ) / [ A g p ( x , Q 0 2 ) ] , we demonstrate that the leading twist approximation for nuclear shadowing provides a good description of all the data on d σ A A → J / ψ A A / d y and σ γ A → J / ψ A ( W γ p ) as well as on the experimental values for S Pb ( x ) derived from σ γ A → J / ψ A ( W γ p ) . We also show that modern nuclear parton distributions reasonably reproduce S Pb ( x ) as well. Published by the American Physical Society 2024

Guzey, V. (ORCID:0000000223938507)↗
DOE OSTI2025

Model for the curvature response of the CDF II drift chamber

The CDF II experiment at the Fermilab Tevatron used a drift chamber to measure the momenta of charged particles. We present a model for the response of the drift chamber to the curvature of a charged particle's trajectory. Constraints on the model parameters are obtained from cosmic-ray data and from information published by CDF in the context of the W boson mass measurement. Implications for the calibration of the drift chamber measurement of momentum are discussed. The robustness of the CDF calibration procedure is demonstrated. The model provides a framework for the analysis of precision magnetic trackers of high-momentum particles. Published by the American Physical Society 2025

47 OTHER INSTRUMENTATION↗
NASA NTRS2017

Would Current International Space Station (ISS) Recycling Life Support Systems Save Mass on a Mars Transit?

The oxygen and water are recycled on the International Space Station (ISS) to save the cost of launching their mass into orbit. Usually recycling systems are justified by showing that their launch mass would be much lower than the mass of the oxygen or water they produce. Short missions such as Apollo or space shuttle directly provide stored oxygen and water, since the needed total mass of oxygen and water is much less than that of there cycling equipment. Ten year or longer missions such as the ISS or a future moon base easily save mass by recycling while short missions of days or weeks do not. Mars transit and long Mars surface missions have an intermediate duration, typically one to one and a half years. Some of the current ISS recycling systems would save mass if used on a Mars transit but others would not.

mass↗
DOE OSTI2023

Third order QCD predictions for fiducial W -boson production

Measurements of W-boson production at the LHC have reached percent-level precision and impose challenging demands on theoretical predictions. Such predictions directly limit the precision of measurements of fundamental quantities such as the W-boson mass and the weak mixing angle. A dominant source of uncertainty in predictions is from higher-order QCD effects. We present a calculation of W-boson production at the level of $α^3_s$ at fixed order and including transverse-momentum resummation. We further show predictions for a direct comparison with low-pileup ATLAS transverse-momentum and fiducial cross-section measurements at $\sqrt{s}$ = 5.02 TeV. We discuss in detail the impact of modern PDFs. Our calculation including the matching to W+jet production at NNLO will be publicly available the upcoming CuTe-MCFM release and allows for theory-data comparison at the state-of-the-art level.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗