scholarly journals Performance study of the relative decay width measurement in hadronic decays of Z boson at CEPC by using the template method

2021 ◽  
Author(s):  
Bo Li ◽  
Yanyan Du ◽  
Zhijun Liang ◽  
Bo Liu
Keyword(s):  
Particle Physics ◽  
High Performance ◽  
Center Of Mass ◽  
Test Procedure ◽  
Real Data ◽  
Template Method ◽  
Performance Study ◽  
Center Of Mass Energy ◽  
The Difference ◽  
Input Variables

The Circular Electron Positron Collider (CEPC) was proposed by the Chinese particle physics scientists as a future Higgs factory and [Formula: see text] factory. It will produced more than [Formula: see text] [Formula: see text] bosons by operating at a center-of-mass energy around 91.2 GeV in two years. In this study, the measurement of the relative decay widths of [Formula: see text] bosons decaying to [Formula: see text] quarks [Formula: see text], [Formula: see text] quarks [Formula: see text] and light quarks [Formula: see text] in hadronic [Formula: see text] decays are studied on CEPC Monte Carlo (MC) samples. By using a template method, [Formula: see text], [Formula: see text] and [Formula: see text] can be fitted from reconstructed data as the fractions of MC templates with different flavors. The distribution of a sensitive variable, [Formula: see text]-tagging probability, is used as the template, because of its high performance in discriminating different flavors. Based on the expected statistics of [Formula: see text] [Formula: see text] bosons at CEPC, the statistical uncertainty is estimated to be approximately [Formula: see text] by using the template method, which means that the measurement will no longer be limited by the statistics. Systematic errors arise directly from the difference in the [Formula: see text]-tagging probability distribution between real data and template MC samples. By considering the bias of input variables used for [Formula: see text]-tagging probability computing, the quantitative effect for each kind of input variable is investigated by using an ensemble test procedure.

scholarly journals Empirical Study of Omnichannel Purchasing Pattern with Real Customer Data from Health and Lifestyle Company

2019 ◽  
Vol 11 (24) ◽  
pp. 7185 ◽  
Author(s):  
Jongsoo Kang ◽  
Marko Majer ◽  
Hyun-Jung Kim
Keyword(s):  
High Performance ◽  
Statistical Significance ◽  
Real Data ◽  
Usage Pattern ◽  
Customer Data ◽  
Customer Group ◽  
Trading Period ◽  
Online Channel ◽  
The Difference ◽  
Offline Channels

This study examines the effect of omnichannel usage pattern on customers’ purchasing amount by determining statistical significance of different purchasing amount occurred for online and offline channel usage pattern with empirical analysis. The data is collected from a health and lifestyle company operated by Major Pharmaceutical company in Korea, which sells health supplement and skincare products through their owned online and offline channels. The channel usage pattern of customers is categorized into four groups: Customer using online channel only, customer using offline channel only, customer first joined membership through online and use both on/offline channels and customers joined membership through offline channel and use both on/offline. Then, the trading period, total number of purchasing, average purchasing amount per transaction and total purchasing amount during trading period among the above four groups were analyzed. The result demonstrated the number of purchasing, average purchasing amount and total purchasing amount for the omnichannel customer groups who cross used on and offline showed statistical significance. However, the difference in purchasing amount between the group of customers who joined online membership and use offline channel and another customer group that joined offline membership and use online channel was not statistically significant. This study overcame the limitation of conventional studies used survey based data, by the application of empirical data from the real customers in on/offline channels, and provides meaningful insights based on empirical real data that group of customers with higher purchasing experience in both on/offline channels shows high performance.

scholarly journals REVIEW OF PROPERTIES OF THE TOP QUARK FROM MEASUREMENTS AT THE TEVATRON

2009 ◽  
Vol 24 (16n17) ◽  
pp. 2899-3037 ◽  
Author(s):  
MARC-ANDRÉ PLEIER
Keyword(s):  
Top Quark ◽  
Particle Physics ◽  
Quark Mass ◽  
Center Of Mass ◽  
Top Quarks ◽  
Mass Energy ◽  
Fundamental Particle ◽  
Proton Antiproton ◽  
Center Of Mass Energy ◽  
Elementary Particle Physics

This review summarizes the program in the physics of the top quark being pursued at Fermilab's Tevatron proton–antiproton collider at a center-of-mass energy of 1.96 TeV. More than a decade after the discovery of the top quark at the two collider detectors CDF and D0, the Tevatron has been the only accelerator to produce top quarks and to study them directly.The Tevatron's increased luminosity and center-of-mass energy offer the possibility to scrutinize the properties of this heaviest fundamental particle through new measurements that were not feasible before, such as the first evidence for electroweak production of top quarks and the resulting direct constraints on the involved couplings. Better measurements of top quark properties provide more stringent tests of predictions from the SM of elementary particle physics. In particular, the improvement in measurements of the mass of the top quark, with the latest uncertainty of 0.7% marking the most precisely measured quark mass to date, further constrains the prediction of the mass of the still to be discovered Higgs boson.

scholarly journals Future Circular Colliders

2019 ◽  
Vol 69 (1) ◽  
pp. 389-415 ◽  
Author(s):  
M. Benedikt ◽  
A. Blondel ◽  
P. Janot ◽  
M. Klein ◽  
M. Mangano ◽  
...  
Keyword(s):  
Particle Physics ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Heavy Ion ◽  
New Physics ◽  
Proton Proton ◽  
Proton Collisions ◽  
Center Of Mass Energy ◽  
Physics Program ◽  
Electron Positron

After 10 years of physics at the Large Hadron Collider (LHC), the particle physics landscape has greatly evolved. Today, a staged Future Circular Collider (FCC), consisting of a luminosity-frontier highest-energy electron–positron collider (FCC-ee) followed by an energy-frontier hadron collider (FCC-hh), promises the most far-reaching physics program for the post-LHC era. FCC-ee will be a precision instrument used to study the Z, W, Higgs, and top particles, and will offer unprecedented sensitivity to signs of new physics. Most of the FCC-ee infrastructure could be reused for FCC-hh, which will provide proton–proton collisions at a center-of-mass energy of 100 TeV and could directly produce new particles with masses of up to several tens of TeV. This collider will also measure the Higgs self-coupling and explore the dynamics of electroweak symmetry breaking. Thermal dark matter candidates will be either discovered or conclusively ruled out by FCC-hh. Heavy-ion and electron–proton collisions (FCC-eh) will further contribute to the breadth of the overall FCC program. The integrated FCC infrastructure will serve the particle physics community through the end of the twenty-first century. This review combines key contents from the first three volumes of the FCC Conceptual Design Report.

scholarly journals Interpretation of LHC excesses in ditop and ditau channels as a 400-GeV pseudoscalar resonance

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Ernesto Arganda ◽  
Leandro Da Rold ◽  
Daniel A. Díaz ◽  
Anibal D. Medina
Keyword(s):  
Particle Physics ◽  
Center Of Mass ◽  
Higgs Doublet ◽  
New Physics ◽  
Atlas Collaboration ◽  
Final State ◽  
Center Of Mass Energy ◽  
Heavy Resonances ◽  
Phenomenological Perspective ◽  
The Look

Abstract Since the discovery in 2012 of the Higgs boson at the LHC, as the last missing piece of the Standard Model of particle physics, any hint of new physics has been intensively searched for, with no confirmation to date. There are however slight deviations from the SM that are worth investigating. The CMS collaboration has reported, in a search for heavy resonances decaying in t$$ \overline{t} $$ t ¯ with a 13-TeV center-of-mass energy and a luminosity of 35.9 fb−1, deviations from the SM predictions at the 3.5σ level locally (1.9σ after the look-elsewhere effect). In addition, in the ditau final state search performed by the ATLAS collaboration at $$ \sqrt{s} $$ s = 13 TeV and $$ \mathcal{L} $$ L = 139 fb−1, deviations from the SM at the 2σ level have been also observed. Interestingly, both slight excesses are compatible with a new pseudoscalar boson with a mass around 400 GeV that couples at least to fermions of the third generation and gluons. Starting from a purely phenomenological perspective, we inspect the possibility that a 400-GeV pseudoscalar can account for these deviations and at the same time satisfy the constraints on the rest of the channels that it gives contributions to and that are analyzed by the ATLAS and CMS experiments. After obtaining the range of effective couplings compatible with all experimental measurements, we study the gauge invariant UV completions that can give rise to this type of pseudoscalar resonance, which can be accommodated in an SO(6)/SO(5) model with consistency at the 1σ level and in a SO(5) × U(1)P × U(1)X/SO(4) × U(1)X at the 2σ level, while exceedingly large quartic couplings would be necessary to account for it in a general two Higgs doublet model.

scholarly journals SIMULATION OF A HYBRID OPTICAL/RADIO/ACOUSTIC EXTENSION TO ICECUBE FOR EHE NEUTRINO DETECTION

2006 ◽  
Vol 21 (supp01) ◽  
pp. 259-264 ◽  
Author(s):  
J. A. VANDENBROUCKE ◽  
D. BESSON ◽  
S. BÖSER ◽  
R. NAHNHAUER ◽  
P. B. PRICE
Keyword(s):  
Particle Physics ◽  
Center Of Mass ◽  
Cosmic Ray ◽  
Center Of Mass Energy ◽  
Neutrino Detection ◽  
Test Models ◽  
Astrophysical Neutrinos ◽  
Event Rates ◽  
Hybrid Detector ◽  
Source Of Information

Astrophysical neutrinos at ~EeV energies promise to be an interesting source of information for astrophysics and particle physics. Detecting the predicted cosmogenic ("GZK") neutrinos at 1016 - 1020 eV would test models of cosmic ray production at these energies and probe particle physics at ~100 TeV center-of-mass energy. While IceCube could detect ~1 GZK event per year, it is necessary to detect 10 or more events per year in order to study temporal, angular, and spectral distributions. The IceCube observatory may be able to achieve such event rates with an extension including optical, radio, and acoustic receivers. We present results from simulating such a hybrid detector.

scholarly journals Feasibility study of TPC tracker detector for the circular collider

2020 ◽  
Vol 35 (15n16) ◽  
pp. 2041014 ◽  
Author(s):  
Zhiyang Yuan ◽  
Huirong Qi ◽  
Haiyun Wang ◽  
Hongliang Dai ◽  
Yuanbo Chen ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Particle Physics ◽  
Center Of Mass ◽  
Silicon Detector ◽  
Concept Design ◽  
Great Opportunity ◽  
Baseline Design ◽  
Detector Module ◽  
Center Of Mass Energy ◽  
Time Projection

The discovery of a SM Higgs boson at the LHC brought about great opportunity to investigate the feasibility of a Circular Electron Positron Collider (CEPC) operating at center-of-mass energy of 240 GeV, as a Higgs factory, with designed luminosity of about [Formula: see text]. The CEPC provides a much cleaner collision environment than the LHC, it is ideally suited for studying the properties of Higgs boson with greater precision. Another advantage of the CEPC over the LHC is that the Higgs boson can be detected through the recoil mass method by only reconstructing [Formula: see text] boson decay without examining the Higgs decays. In Concept Design Report (CDR), the circumference of CEPC is 100 km, with two interaction points available for exploring different detector design scenarios and technologies. The baseline design of CEPC detector is an ILD-like concept, with a superconducting solenoid of 3.0 Tesla surrounding the inner silicon detector, TPC tracker detector and the calorimetry system. Time Projection Chambers (TPCs) have been extensively studied and used in many fields, especially in particle physics experiments, including STAR and ALICE. The TPC detector will operate in continuous mode on the circular machine. To fulfill the physics goals of the future circular collider and meet Higgs/[Formula: see text] run, a TPC with excellent performance is required. We have proposed and investigated the ions controlling performance of a novel configuration detector module. The aim of this study is to suppress ion backflow (IBF) continually. In this paper, some update results of the feasibility and limitation on TPC detector technology R&D will be given using the hybrid gaseous detector module.

Exploring Baryon Rich Matter with Heavy-Ion Collisions

2019 ◽  
Vol 64 (7) ◽  
pp. 583 ◽  
Author(s):  
S. Harabasz
Keyword(s):  
Center Of Mass ◽  
Heavy Ion ◽  
State Density ◽  
Heavy Nuclei ◽  
First Order ◽  
Center Of Mass Energy ◽  
Ion Collisions ◽  
Deconfinement Phase Transition ◽  
Ground State Density

Collisions of heavy nuclei at (ultra-)relativistic energies provide a fascinating opportunity to re-create various forms of matter in the laboratory. For a short extent of time (10-22 s), matter under extreme conditions of temperature and density can exist. In dedicated experiments, one explores the microscopic structure of strongly interacting matter and its phase diagram. In heavy-ion reactions at SIS18 collision energies, matter is substantially compressed (2–3 times ground-state density), while moderate temperatures are reached (T < 70 MeV). The conditions closely resemble those that prevail, e.g., in neutron star mergers. Matter under such conditions is currently being studied at the High Acceptance DiElecton Spectrometer (HADES). Important topics of the research program are the mechanisms of strangeness production, the emissivity of matter, and the role of baryonic resonances herein. In this contribution, we will focus on the important experimental results obtained by HADES in Au+Au collisions at 2.4 GeV center-of-mass energy. We will also present perspectives for future experiments with HADES and CBM at SIS100, where higher beam energies and intensities will allow for the studies of the first-order deconfinement phase transition and its critical endpoint.

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