Systematic Uncertainties

Abstract We estimate the form factors that parametrise the hadronic matrix elements of proton-to-pion transitions with the help of light-cone sum rules. These form factors are relevant for semi-leptonic proton decay channels induced by baryon-number violating dimension-six operators, as typically studied in the context of grand unified theories. We calculate the form factors in a kinematical regime where the momentum transfer from the proton to the pion is space-like and extrapolate our final results to the regime that is relevant for proton decay. In this way, we obtain estimates for the form factors that show agreement with the state-of-the-art calculations in lattice QCD, if systematic uncertainties are taken into account. Our work is a first step towards calculating more involved proton decay channels where lattice QCD results are not available at present.

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Optimising top-quark threshold scan at CLIC using genetic algorithm

Journal of High Energy Physics ◽

10.1007/jhep07(2021)070 ◽

2021 ◽

Vol 2021 (7) ◽

Author(s):

K. Nowak ◽

A.F. Żarnecki

Keyword(s):

Genetic Algorithm ◽

Pair Production ◽

Top Quark ◽

Quark Mass ◽

Mass Measurement ◽

Production Cross ◽

Model Parameters ◽

Top Quark Mass ◽

Systematic Uncertainties ◽

Pair Production Cross Section

Abstract One of the important goals at the future e+e− colliders is to measure the top-quark mass and width in a scan of the pair production threshold. However, the shape of the pair-production cross section at the threshold depends also on other model parameters, as the top Yukawa coupling, and the measurement is a subject to many systematic uncertainties. Presented in this work is the study of the top-quark mass determination from the threshold scan at CLIC. The most general approach is used with all relevant model parameters and selected systematic uncertainties included in the fit procedure. Expected constraints from other measurements are also taken into account. It is demonstrated that the top-quark mass can be extracted with precision of the order of 30 to 40 MeV, including considered systematic uncertainties, already for 100 fb−1 of data collected at the threshold. Additional improvement is possible, if the running scenario is optimised. With the optimisation procedure based on the genetic algorithm the statistical uncertainty of the mass measurement can be reduced by about 20%. Influence of the collider luminosity spectra on the expected precision of the measurement is also studied.

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Probing neutrino magnetic moment at the Jinping neutrino experiment

Journal of High Energy Physics ◽

10.1007/jhep08(2021)068 ◽

2021 ◽

Vol 2021 (8) ◽

Author(s):

Baobiao Yue ◽

Jiajun Liao ◽

Jiajie Ling

Keyword(s):

Magnetic Moment ◽

Liquid Scintillator ◽

Solar Neutrinos ◽

Electron Neutrino ◽

Neutrino Experiment ◽

Neutrino Magnetic Moment ◽

Systematic Uncertainties ◽

Electron Recoil ◽

Massive Neutrinos ◽

Highly Correlated

Abstract Neutrino magnetic moment (νMM) is an important property of massive neutrinos. The recent anomalous excess at few keV electronic recoils observed by the XENON1T collaboration might indicate a ∼ 2.2 × 10−11μB effective neutrino magnetic moment ($$ {\mu}_{\nu}^{\mathrm{eff}} $$ μ ν eff ) from solar neutrinos. Therefore, it is essential to carry out the νMM searches at a different experiment to confirm or exclude such a hypothesis. We study the feasibility of doing νMM measurement with 4 kton fiducial mass at Jinping neutrino experiment (Jinping) using electron recoil data from both natural and artificial neutrino sources. The sensitivity of $$ {\mu}_{\nu}^{\mathrm{eff}} $$ μ ν eff can reach < 1.2 × 10−11μB at 90% C.L. with 10-year data taking of solar neutrinos. Besides the abundance of the intrinsic low energy background 14C and 85Kr in the liquid scintillator, we find the sensitivity to νMM is highly correlated with the systematic uncertainties of pp and 85Kr. Reducing systematic uncertainties (pp and 85Kr) and the intrinsic background (14C and 85Kr) can help to improve sensitivities below these levels and reach the region of astrophysical interest. With a 3 mega-Curie (MCi) artificial neutrino source 51Cr installed at Jinping neutrino detector for 55 days, it could give us a sensitivity to the electron neutrino magnetic moment ($$ {\mu}_{\nu_e} $$ μ ν e ) with < 1.1 × 10−11μB at 90% C.L. . With the combination of those two measurements, the flavor structure of the neutrino magnetic moment can be also probed at Jinping.

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HUBBLE SPACE TELESCOPECOMBINED STRONG AND WEAK LENSING ANALYSIS OF THE CLASH SAMPLE: MASS AND MAGNIFICATION MODELS AND SYSTEMATIC UNCERTAINTIES

The Astrophysical Journal ◽

10.1088/0004-637x/801/1/44 ◽

2015 ◽

Vol 801 (1) ◽

pp. 44 ◽

Cited By ~ 131

Author(s):

Adi Zitrin ◽

Agnese Fabris ◽

Julian Merten ◽

Peter Melchior ◽

Massimo Meneghetti ◽

...

Keyword(s):

Weak Lensing ◽

Sample Mass ◽

Systematic Uncertainties

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Commissioning of a High Pressure Time Projection Chamber with Optical Readout

Instruments ◽

10.3390/instruments5020022 ◽

2021 ◽

Vol 5 (2) ◽

pp. 22

Author(s):

Alexander Deisting ◽

Abigail Waldron ◽

Edward Atkin ◽

Gary Barker ◽

Anastasia Basharina-Freshville ◽

...

Keyword(s):

High Pressure ◽

Neutrino Oscillation ◽

Time Projection Chamber ◽

Neutrino Experiment ◽

Long Baseline ◽

Neutrino Oscillation Experiment ◽

Optical Readout ◽

Systematic Uncertainties ◽

Pressure Time ◽

Time Projection

The measurements of proton–nucleus scattering and high resolution neutrino–nucleus interaction imaging are key in reducing neutrino oscillation systematic uncertainties in future experiments. A High Pressure Time Projection Chamber (HPTPC) prototype has been constructed and operated at the Royal Holloway University of London and CERN as a first step in the development of a HPTPC that is capable of performing these measurements as part of a future long-baseline neutrino oscillation experiment, such as the Deep Underground Neutrino Experiment. In this paper, we describe the design and operation of the prototype HPTPC with an argon based gas mixture. We report on the successful hybrid charge and optical readout using four CCD cameras of signals from 241Am sources.

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