scholarly journals Observation of an exotic narrow doubly charmed tetraquark

2021 ◽  
Author(s):  
Ivan Belyaev
Keyword(s):  
Mass Spectrum ◽  
Hadron Collider ◽  
Hadronic Matter ◽  
Exotic State ◽  
Charm Quarks ◽  
Hadronic State ◽  
New Type ◽  
Narrow Width ◽  
Using Data ◽  
Resonance Nature

Abstract Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. The observation of a new type of hadronic state, a doubly charmed tetraquark containing two charm quarks, an anti-u and an anti-d quark, is reported using data collected by the LHCb experiment at the Large Hadron Collider. This exotic state with a mass of about 3875 MeV/c 2 manifests itself as a narrow peak in the mass spectrum of D0D0π + mesons just below the D∗+D0 mass threshold. The near-threshold mass together with a strikingly narrow width reveals the resonance nature of the state.

STUDY OF THE DIJET INVARIANT MASS IN W + JETS EVENTS BY THE DØ COLLABORATION

2012 ◽  
Vol 27 (01) ◽  
pp. 1230002
Author(s):  
JADRANKA SEKARIC
Keyword(s):  
Mass Spectrum ◽  
Invariant Mass ◽  
Experimental Verification ◽  
Hadron Collider ◽  
Mass Range ◽  
Invariant Mass Spectrum ◽  
Dijet Production ◽  
Dijet Mass ◽  
Two Jets ◽  
Recent Claim

The recent claim by the CDF Collaboration of a possible anomalous dijet resonance in their data required experimental verification from other hadron collider experiments. We present a study of the dijet invariant mass spectrum in events with two jets produced in association with a W→ℓν boson at the DØ experiment. We investigate the dijet mass range between 110 GeV /c2 and 170 GeV /c2 and find no evidence for any resonant dijet production.

scholarly journals SUPERSYMMETRY VERSUS BLACK HOLES AT THE LHC

2008 ◽  
Vol 23 (35) ◽  
pp. 2987-2996 ◽  
Author(s):  
ARUNAVA ROY ◽  
MARCO CAVAGLIÀ
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Mass Spectrum ◽  
Large Hadron Collider ◽  
Extra Dimensions ◽  
Hadron Collider ◽  
New Physics ◽  
Event Shape ◽  
High Transverse Momentum ◽  
Dilepton Invariant Mass

Supersymmetry and extra dimensions are the two most promising candidates for new physics at the TeV scale. Supersymmetric particles or extra-dimensional effects could soon be observed at the Large Hadron Collider. We propose a simple but effective method to discriminate the two models: the analysis of isolated leptons with high transverse momentum. Black hole events are simulated with the CATFISH black hole generator. Supersymmetry simulations use a combination of PYTHIA and ISAJET, the latter providing the mass spectrum. Our results show that the measure of the dilepton invariant mass provides a promising signature to differentiate supersymmetry and black hole events at the Large Hadron Collider. Analysis of event-shape variables and multilepton events complement and strengthen this conclusion.

Search for new particles

1977 ◽  
Vol 355 (1683) ◽  
pp. 493-513
Keyword(s):  
Mass Spectrum ◽  
Proton Beam ◽  
High Intensity ◽  
National Laboratory ◽  
Brookhaven National Laboratory ◽  
New Type ◽  
New Particles

We present a description of an experiment carried out at the 30GeV Alternating Gradient Synchrotron of the Brookhaven National Laboratory. The experiment used a high intensity slow extracted proton beam of between 10 10 and 2 × 10 12 protons per pulse and measured the e + e - mass spectrum from the reaction p+Be→e + e - +X. The result of this experiment shows the production of a new type of particle, J, which decays to e + e - with a width consistent with zero. Experimental searches for more new particles will also be presented.

Design of Hybrid Reconstruction Scheme for Compressible Flow Using Data-Driven Methods

2020 ◽  
Vol 36 (5) ◽  
pp. 675-689
Author(s):  
A. Salazar ◽  
F. Xiao
Keyword(s):  
Machine Learning ◽  
Compressible Flow ◽  
Machine Learning Techniques ◽  
Hybrid Scheme ◽  
Solution Quality ◽  
Hybrid Schemes ◽  
New Type ◽  
Switching Criterion ◽  
Using Data ◽  
Discontinuous Data

ABSTRACTExisting numerical schemes used to solve the governing equations for compressible flow suffer from dissipation errors which tend to smear out sharp discontinuities. Hybrid schemes show potential improvements in this challenging problem; however, the solution quality of a hybrid scheme heavily depends on the criterion to switch between the different candidate reconstruction functions. This work presents a new type of switching criterion (or selector) using machine learning techniques. The selector is trained with randomly generated samples of continuous and discontinuous data profiles, using the exact solution of the governing equation as a reference. Neural networks and random forests were used as the machine learning frameworks to train the selector, and it was later implemented as the indicator function in a hybrid scheme which includes THINC and WENO-Z as the candidate reconstruction functions. The trained selector has been verified to be effective as a reliable switching criterion in the hybrid scheme, which significantly improves the solution quality for both advection and Euler equations.

scholarly journals Measurements of top-quark pair differential and double-differential cross-sections in the $$\ell $$+jets channel with pp collisions at $$\sqrt{s}=13$$ TeV using the ATLAS detector

2019 ◽  
Vol 79 (12) ◽  
Author(s):  
G. Aad ◽  
◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Top Quark ◽  
Hadron Collider ◽  
Atlas Detector ◽  
Double Differential Cross Section ◽  
Quark Pairs ◽  
Top Quark Production ◽  
Using Data

AbstractSingle- and double-differential cross-section measurements are presented for the production of top-quark pairs, in the lepton + jets channel at particle and parton level. Two topologies, resolved and boosted, are considered and the results are presented as a function of several kinematic variables characterising the top and $$t\bar{t}$$ t t ¯ system and jet multiplicities. The study was performed using data from pp collisions at centre-of-mass energy of 13 TeV collected in 2015 and 2016 by the ATLAS detector at the CERN Large Hadron Collider (LHC), corresponding to an integrated luminosity of $$36~\mathrm {fb}^{-1}$$ 36 fb - 1 . Due to the large $$t\bar{t}$$ t t ¯ cross-section at the LHC, such measurements allow a detailed study of the properties of top-quark production and decay, enabling precision tests of several Monte Carlo generators and fixed-order Standard Model predictions. Overall, there is good agreement between the theoretical predictions and the data.

Online Participation in the UK: Testing a ‘Contextualised’ Model of Internet Effects

2005 ◽  
Vol 7 (4) ◽  
pp. 561-583 ◽  
Author(s):  
Rachel K. Gibson ◽  
Wainer Lusoli ◽  
Stephen Ward
Keyword(s):  
Political Activity ◽  
The Internet ◽  
Online Environment ◽  
Online Participation ◽  
Empirical Modelling ◽  
Explanatory Factors ◽  
New Type ◽  
Using Data ◽  
The Uk ◽  
Politically Active

This article offers a new test of the mobilisation thesis of Internet effects on individual political participation using data from an NOP survey of 1,972 UK adults during May 2002. The analysis differs from that of previous studies in that it significantly widens the understanding of the dependent variable—online participation—as well as introducing new Internet-specific variables as explanatory factors for this new type of participation. Using this broader ‘contextualised’ model of online political activity we find support for the idea that the Internet is expanding the numbers of the politically active, specifically in terms of reaching groups that are typically inactive or less active in conventional or offline forms of politics. In drawing these conclusions our article joins with a growing body of literature calling for the re-evaluation of the so-called normalisation thesis which argues that ultimately the Internet will lead to a further narrowing of the pool of politically active citizens by reinforcing existing levels of engagement. At a broader level we consider the findings point to the need for scholars in the area to work towards a more sophisticated theoretical and empirical modelling of participation in the online environment.

scholarly journals Analyzing Particularities of Sensor Datasets for Supporting Data Understanding and Preparation

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6063
Author(s):  
Francisco Javier Nieto ◽  
Unai Aguilera ◽  
Diego López-de-Ipiña
Keyword(s):  
Decision Making ◽  
Data Cleaning ◽  
Sensor Data ◽  
Statistical Distributions ◽  
Decision Making Processes ◽  
New Type ◽  
Measurement Units ◽  
Using Data ◽  
Different Sources ◽  
Existing Data

Data scientists spend much time with data cleaning tasks, and this is especially important when dealing with data gathered from sensors, as finding failures is not unusual (there is an abundance of research on anomaly detection in sensor data). This work analyzes several aspects of the data generated by different sensor types to understand particularities in the data, linking them with existing data mining methodologies. Using data from different sources, this work analyzes how the type of sensor used and its measurement units have an important impact in basic statistics such as variance and mean, because of the statistical distributions of the datasets. The work also analyzes the behavior of outliers, how to detect them, and how they affect the equivalence of sensors, as equivalence is used in many solutions for identifying anomalies. Based on the previous results, the article presents guidance on how to deal with data coming from sensors, in order to understand the characteristics of sensor datasets, and proposes a parallelized implementation. Finally, the article shows that the proposed decision-making processes work well with a new type of sensor and that parallelizing with several cores enables calculations to be executed up to four times faster.

scholarly journals On Direct Search for Dark Matter in Scattering Processes within Yukawa Model

2021 ◽  
Vol 66 (11) ◽  
pp. 936
Author(s):  
V.V. Skalozub ◽  
M.S. Dmytriiev
Keyword(s):  
Dark Matter ◽  
Mass Spectrum ◽  
Invariant Mass Spectrum ◽  
Resonant Peak ◽  
Yukawa Model ◽  
Narrow Width Approximation ◽  
The Standard Model ◽  
Dark Matters ◽  
Narrow Width

Nowadays, no dark matter candidates have been discovered. We consider two possible reasons for that, both related to the approach of on-peak resonance searching for. As is believed usually, a new particle suits the conditions that the ratio of the width to the mass is less than 1–3% and a narrow-width approximation (NWA) is applicable to identify such type resonant peak in the invariant mass spectrum of the collision products. In the present paper, in the framework of a generalized Yukawa model, we find out the properties of the searched particle, when its width is larger than a maximal one expected during experiments, and, so, this state could be confused with a noise. We also ascertain the values of particle’s parameters, when the NWA is not applicable and estimate the width value, when it happens. These estimations are relevant to interactions between the Standard model and dark matter particles. Such approach is focused on the role of couplings and mass values introduced in the model describing the interaction of visible and dark matters.

Factors Affecting Customer Intentions Toward AI-Made Music

2022 ◽  
pp. 195-220
Author(s):  
Bình Nghiêm-Phú
Keyword(s):  
Theoretical Model ◽  
Personal Characteristics ◽  
Factors Affecting ◽  
Practical Support ◽  
Product Service ◽  
New Type ◽  
Using Data ◽  
The One ◽  
Customer Attitudes ◽  
Young Customer

The purpose of this chapter was to develop and verify a theoretical model to understand the ways that potential customers perceive and act toward AI-made products. The author began the chapter with a review of the existing literature to extract the most fundamental elements, both internal and external to the customers, which can affect their perceptions and behaviours. From there, the author proposed and tested a theoretical model that can explain customer attitudes toward a new type of music: AI-made music. Using data gathered from a young customer sample (n = 219) in Japan, the author found that perceived product/service attributes and customers' personal characteristics had significant impacts on customer purchase intentions, while perceived seller attributes and environment characteristics had not. These findings helped expand the literature on customer attitudes by introducing and investigating an aggregated model on the one hand. They also provided practical support for the commercialization of the AI-made products industry in the future on the other.

Sign in / Sign up

Export Citation Format

Share Document