Publications by authors named "K A Grimm"

High-energy nuclear collisions create a quark-gluon plasma, whose initial condition and subsequent expansion vary from event to event, impacting the distribution of the eventwise average transverse momentum [P([p_{T}])]. Disentangling the contributions from fluctuations in the nuclear overlap size (geometrical component) and other sources at a fixed size (intrinsic component) remains a challenge. This problem is addressed by measuring the mean, variance, and skewness of P([p_{T}]) in ^{208}Pb+^{208}Pb and ^{129}Xe+^{129}Xe collisions at sqrt[s_{NN}]=5.

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According to the Flynn effect, performance on cognitive ability tests has improved over the past decades. However, we know very little about whether such historical improvements generalize to middle-aged adults (aged 45-65) and differ across nations. We used harmonized data on episodic memory from nationally representative longitudinal panel surveys across a total of 16 countries (United States, Mexico, China, England, and countries in Continental, Mediterranean, and Nordic Europe).

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Article Synopsis
  • Structural Equation Modeling (SEM) is gaining traction in research, but there is a lack of resources for users to grasp its complex analytic steps comprehensively.
  • This work builds on Ferron and Hess's 2007 study by providing Python code for key SEM processes like specification, estimation, and optimization.
  • It enhances the original study by including advanced notations and mean estimation, along with supplementary code in the appendix for users to follow along.
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A search for the exclusive hadronic decays W^{±}→π^{±}γ, W^{±}→K^{±}γ, and W^{±}→ρ^{±}γ is performed using up to 140  fb^{-1} of proton-proton collisions recorded with the ATLAS detector at a center-of-mass energy of sqrt[s]=13  TeV. If observed, these rare processes would provide a unique test bench for the quantum chromodynamics factorization formalism used to calculate cross sections at colliders. Additionally, at future colliders, these decays could offer a new way to measure the W boson mass through fully reconstructed decay products.

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Article Synopsis
  • - The ATLAS experiment at the LHC conducted a search for long-lived particles (LLPs) using a large dataset (140 fb^{-1}) from proton-proton collisions at 13 TeV, focusing on LLPs with masses from 5 to 55 GeV that decay within the inner detector.
  • - The study considered scenarios where LLPs are produced from exotic Higgs boson decays and models involving axionlike particles (ALPs).
  • - No significant findings above expected background levels were detected, leading to the establishment of upper limits on various production rates involving the Higgs boson and the top quark related to LLPs and ALPs.
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