A search for the top and b′ quarks in hadronic Z0 decays

AbstractWe describe a method to obtain point and dispersion estimates for the energies of jets arising from b quarks produced in proton–proton collisions at an energy of $$\sqrt{s}=13\,\text {TeV} $$ s = 13 TeV at the CERN LHC. The algorithm is trained on a large sample of simulated b jets and validated on data recorded by the CMS detector in 2017 corresponding to an integrated luminosity of 41 $$\,\text {fb}^{-1}$$ fb - 1 . A multivariate regression algorithm based on a deep feed-forward neural network employs jet composition and shape information, and the properties of reconstructed secondary vertices associated with the jet. The results of the algorithm are used to improve the sensitivity of analyses that make use of b jets in the final state, such as the observation of Higgs boson decay to $$\hbox {b}\bar{\hbox {b}}$$ b b ¯ .

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Correlation of Heavy and Light Flavors in Simulations

Universe ◽

10.3390/universe5050118 ◽

2019 ◽

Vol 5 (5) ◽

pp. 118

Author(s):

Eszter Frajna ◽

Róbert Vértesi

Keyword(s):

Large Hadron Collider ◽

Heavy Ion Collisions ◽

Hadron Collider ◽

D Meson ◽

Heavy Ion ◽

High Energy ◽

Secondary Vertex ◽

Alice Experiment ◽

Ion Collisions ◽

B Quarks

The ALICE experiment at the Large Hadron Collider (LHC) ring is designed to study the strongly interacting matter at extreme energy densities created in high-energy heavy-ion collisions. In this paper we investigate correlations of heavy and light flavors in simulations at LHC energies at mid-rapidity, with the primary purpose of proposing experimental applications of these methods. Our studies have shown that investigating the correlation images can aid the experimental separation of heavy quarks and help understanding the physics that create them. The shape of the correlation peaks can be used to separate the electrons stemming from b quarks. This could be a method of identification that, combined with identification in silicon vertex detectors, may provide much better sample purity for examining the secondary vertex shift. Based on a correlation picture it is also possible to distinguish between prompt and late contributions to D meson yields.

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Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos and b quarks at s = 13 $$ \sqrt{s}=13 $$ TeV

Journal of High Energy Physics ◽

10.1007/jhep11(2018)172 ◽

2018 ◽

Vol 2018 (11) ◽

Cited By ~ 2

Author(s):

A. M. Sirunyan ◽

◽

A. Tumasyan ◽

W. Adam ◽

F. Ambrogi ◽

...

Keyword(s):

Higgs Boson ◽

Vector Boson ◽

Final States ◽

B Quarks ◽

Heavy Resonances ◽

Charged Leptons

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MASSIVE-QUARK BARYONS AS SKYRMIONS

Modern Physics Letters A ◽

10.1142/s0217732391002268 ◽

1991 ◽

Vol 06 (23) ◽

pp. 2087-2100 ◽

Cited By ~ 1

Author(s):

MANNQUE RHO

Keyword(s):

Degrees Of Freedom ◽

Pivotal Role ◽

Massive Scalar ◽

Massive Quark ◽

B Quarks ◽

Quark Models

Massive-quark baryons containing one or more charm (c) or bottom (b) quarks are described as massive scalar doublet fields "wrapped" by the soliton of the light (up and down) flavors. The spin-isospin transmutation that takes place to make the trapped scalar behave like heavy-flavored quarks is analogous to what happens to a scalar doublet in the presence of a 't Hooft–Polyakov monopole. The Wess–Zumino term plays a pivotal role here. This model predicts spectra that resemble closely those of quark models. This feature is interpreted in terms of an induced gauge (or Berry) structure associated with "fast" and "slow" degrees of freedom corresponding, respectively, to the massive- and light-flavor quarks involved in the baryon structure.

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Tests of Lepton Flavour Universality at LHCb

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194518600704 ◽

2018 ◽

Vol 46 ◽

pp. 1860070

Author(s):

Anna Lupato

Keyword(s):

Standard Model ◽

Beyond The Standard Model ◽

Centre Of Mass ◽

Gauge Bosons ◽

B Quarks ◽

Clear Sign ◽

The Standard Model ◽

8 Tev ◽

Using Data ◽

Lepton Flavour

In the Standard Model the electroweak coupling of the gauge bosons to leptons is independent of the lepton flavour. Semileptonic and rare decays of b quarks provide an ideal laboratory to test this property. Any violation of Lepton Flavour Universality would be a clear sign of physics beyond the Standard Model. In this work a review of the Lepton Flavour Universality tests performed using data collected by the LHCb experiment in 2011 and 2012 at a centre of mass energy of 7 and 8 TeV is presented.

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