scholarly journals Adequacy of Effective Born for electroweak effects and TauSpinner algorithms for high energy physics simulated samples

2022 ◽  
Vol 137 (1) ◽  
Author(s):  
E. Richter-Was ◽  
Z. Was

AbstractMatching and comparing the measurements of past and future experiments call for consistency checks of electroweak (EW) calculations used for their interpretation. On the other hand, new calculation schemes of the field theory can be beneficial for precision, even if they may obscure comparisons with earlier results. Over the years, concepts of Improved Born, Effective Born, as well as of effective couplings, in particular of $$\sin ^2\theta _W^{{\textit{eff}}}$$ sin 2 θ W eff mixing angle for EW interactions, have evolved. In our discussion, we use four versions of EW library for phenomenology of practically all HEP accelerator experiments over the last 30 years. We rely on the codes published and archived with the Monte Carlo program for $$e^+e^- \rightarrow f {\bar{f}} n(\gamma )$$ e + e - → f f ¯ n ( γ ) and available for the as well. re-weighs generated events for introduction of EW effects. To this end, is first invoked, and its results are stored in data file and later used. Documentation of upgrade, to version 2.1.0, and that of its new arrangement for semi-automated benchmark plots are provided. In our paper, focus is placed on the numerical results, on the different approximations introduced in Improved Born to obtain Effective Born, which is simpler for applications of strong or QED processes in pp or $$e^+e^-$$ e + e - colliders. The $$\tau $$ τ lepton polarization $$P_{\tau }$$ P τ , forward–backward asymmetry $$A_{{\textit{FB}}}$$ A FB and parton-level total cross section $$\sigma ^{{\textit{tot}}}$$ σ tot are used to monitor the size of EW effects and effective $$\sin ^2\theta _W^{{\textit{eff}}}$$ sin 2 θ W eff picture limitations for precision physics. Collected results include: (i) Effective Born approximations and $$\sin ^2\theta _W^{{\textit{eff}}}$$ sin 2 θ W eff , (ii) differences between versions of EW libraries and (iii) parametric uncertainties due to, for example, $$m_t$$ m t or $$\Delta \alpha _h^{(5)}(s)$$ Δ α h ( 5 ) ( s ) . These results can be considered as benchmarks and also allow to evaluate the adequacy of Effective Born with respect to Improved Born. Definitions are addressed too.

2019 ◽  
Vol 214 ◽  
pp. 08004 ◽  
Author(s):  
R. Du ◽  
J. Shi ◽  
J. Zou ◽  
X. Jiang ◽  
Z. Sun ◽  
...  

There are two production clusters co-existed in the Institute of High Energy Physics (IHEP). One is a High Throughput Computing (HTC) cluster with HTCondor as the workload manager, the other is a High Performance Computing (HPC) cluster with Slurm as the workload manager. The resources of the HTCondor cluster are funded by multiple experiments, and the resource utilization reached more than 90% by adopting a dynamic resource share mechanism. Nevertheless, there is a bottleneck if more resources are requested by multiple experiments at the same moment. On the other hand, parallel jobs running on the Slurm cluster reflect some specific attributes, such as high degree of parallelism, low quantity and long wall time. Such attributes make it easy to generate free resource slots which are suitable for jobs from the HTCondor cluster. As a result, if there is a mechanism to schedule jobs from the HTCon-dor cluster to the Slurm cluster transparently, it would improve the resource utilization of the Slurm cluster, and reduce job queue time for the HTCondor cluster. In this proceeding, we present three methods to migrate HTCondor jobs to the Slurm cluster, and concluded that HTCondor-C is more preferred. Furthermore, because design philosophy and application scenes are di↵erent between HTCondor and Slurm, some issues and possible solutions related with job scheduling are presented.


2013 ◽  
Vol 2013 ◽  
pp. 1-3 ◽  
Author(s):  
Ming Li ◽  
Wei Zhao

The golden ratio is an astonishing number in high-energy physics, neutrino physics, and cosmology. The Kolmogorov −5/3 law plays a role in describing energy transfer of random data or random functions. The contributions of this essay are in twofold. One is to express the Kolmogorov −5/3 law by using the golden ratio. The other is to represent the fractal dimension of random data following the Kolmogorov −5/3 law with the golden ratio. It is our hope that this essay may be helpful to provide a new outlook of the Kolmogorov −5/3 law from the point of view of the golden ratio.


2019 ◽  
Vol 204 ◽  
pp. 10011
Author(s):  
Igor Sitnik

Deuteron breakup cross sections on the C and CH2 targets have been measured up to the proton internal momenta of 0.3 GeV/c. The cross-sections 12C(d, p)X and 1H(d, p)X reactions have been obtained with high precision. The obtained data are compared with previous measurements. The behavior features in the vicinity of the cross section maximum were studied in dependence on the transversal momentum in the region of 0.01 < pt < 0.16 GeV/c. The measurements have been performed at the Veksler Baldin Laboratory of High Energy Physics of the Joint Institute for Nuclear Research.


2017 ◽  
Vol 32 (02n03) ◽  
pp. 1730002 ◽  
Author(s):  
Mirco Cannoni

This paper reviews the concept of Lorentz invariant relative velocity that is often misunderstood or unknown in high energy physics literature. The properties of the relative velocity allow to formulate the invariant flux and cross-section without recurring to nonphysical velocities or any assumption about the reference frame. Applications such as the luminosity of a collider, the use as kinematic variable, and the statistical theory of collisions in a relativistic classical gas are reviewed. It is emphasized how the hyperbolic properties of the velocity space explain the peculiarities of relativistic scattering.


2011 ◽  
Vol 26 (25) ◽  
pp. 4511-4520 ◽  
Author(s):  
K. ZHU ◽  
X. H. MO ◽  
C. Z. YUAN ◽  
P. WANG

The recent multiple-solution problem in extracting physics information from a fit to the experimental data in high energy physics is reviewed from a mathematical viewpoint. All these multiple solutions were previously found via a fit process, while in this paper we prove that if the sum of two coherent Breit–Wigner functions is used to fit the measured distribution, there should be two and only two nontrivial solutions, and they are related to each other by analytical formulae. For real experimental measurements in more complicated situations, we also provide a numerical method to derive the other solution from the already obtained one. The excellent consistency between the exact solution obtained this way and the fit process justifies the method. From our results it is clear that the physics interpretation should be very different depending on which solution is selected. So we suggest that all the experimental measurements with potential multiple solutions be re-analyzed to find the other solution because the result is not complete if only one solution is reported.


1997 ◽  
Vol 25 (2-3) ◽  
pp. 88-97 ◽  
Author(s):  
Beverly Woodward

All scientific activity involves some method of observation and some method of recording what is observed. These activities can be carried out in ways that involve little interaction between subject and object, as is the case when a telescope observes a far-away star. At the other end of the scale are experiments in modern high energy physics in which there is little distinction between the observer and the observed, and the process of observation materially affects the data that are recorded. In this regard, research on human phenomena resembles modern physics more than it does classical astronomy.Research on human phenomena, however, differs from modern physics in the way in which it affects that which is observed. Both the procedures and the findings of research on human phenomena alter the modes of thinking and the self-awareness of the (human) objects of study.


2017 ◽  
Vol 3 (5) ◽  
Author(s):  
Alba Cervera-Lierta ◽  
José Latorre ◽  
Juan Rojo ◽  
Luca Rottoli

We analyze how maximal entanglement is generated at the fundamental level in QED by studying correlations between helicity states in tree-level scattering processes at high energy. We demonstrate that two mechanisms for the generation of maximal entanglement are at work: i)ss-channel processes where the virtual photon carries equal overlaps of the helicities of the final state particles, and ii) the indistinguishable superposition between tt- and uu-channels. We then study whether requiring maximal entanglement constrains the coupling structure of QED and the weak interactions. In the case of photon-electron interactions unconstrained by gauge symmetry, we show how this requirement allows to reproduce QED. For ZZ-mediated weak scattering, the maximal entanglement principle leads to non-trivial predictions for the value of the weak mixing angle \theta_WθW. Our results are a first step towards understanding the connections between maximal entanglement and the fundamental symmetries of high-energy physics.


2019 ◽  
Vol 18 ◽  
pp. 49
Author(s):  
M. Zamani ◽  
S. Stoulos ◽  
M. Fragopoulou ◽  
M. Manolopoulou ◽  
N. A. Sosnin ◽  
...  

The inelastic cross section of relativistic protons in Lead was determined indirectly by measuring the neutron distribution along a Lead spallation neutron source. The spallation neutron source was irradiated by 1, 1.5 and 2 GeV protons. The experimental results were taken using passive methods. A fitting procedure has been applied to the experimental data and the results have been compared with analytical calculation of the produced hadrons’ spatial distribution based on High Energy Physics concepts. Using the beam attenuation coefficient the inelastic cross section of protons in Pb was estimated.


1965 ◽  
Vol 86 (8) ◽  
pp. 589-590
Author(s):  
E.V. Shpol'skii

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