# 10th International Workshop on Charm Physics (CHARM 2020)

from 31 May 2021 to 4 June 2021
Mexico/General timezone
Thanks for your contribution to the success of this workshop!!
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## Contribution List

Displaying 203 contributions out of 203
Session: In media
Presented by Mr. Kaifeng SHEN on 3 Jun 2021 at 11:40
Heavy quarkonia are ideal probes of the Quark-Gluon Plasma (QGP). $J/\psi$ is the most abundantly produced quarkonium state accessible experimentally and its suppression due to the color screening effect in hot and dense medium has been suggested as a signature of the formation of the QGP. Besides the screening effect, there are other mechanisms, such as the cold nuclear effects and charm quark re ... More
Presented by Mr. Kaifeng SHEN
Understanding the nature of the hidden charm pentaquark(like) signals in the LHCb data for $\Lambda_b^0\to J/\psi p K^-$ is a central problem of hadron spectroscopy. We propose a scenario completely different from previous ones such as hadron molecules and compact pentaquarks. We identify relevant double triangle mechanisms with leading or lower-order singularities. The associated anomalous thre ... More
Presented by Dr. Satoshi NAKAMURA
Presented by Dr. Satoshi NAKAMURA on 3 Jun 2021 at 11:40
Presented by Mr. William PARROTT on 4 Jun 2021 at 13:10
Semileptonic $D \to{}K \ell \nu$ decays provide one angle of attack to get at the CKM matrix element $V_{cs}$, complementary to the study of leptonic $D_s$ decays. Here we present the results of an improved determination of $V_{cs}$, recently released on the arXiv (2104.09883). With a new, precise determination of $D\to K$ scalar and vector form factors from lattice QCD, combined with experime ... More
Presented by Mr. William PARROTT
We present in full analytic form the partial widths for the lepton flavour violating decays $L^\pm \to \ell^\pm \ell'^{+} \ell'^{-}$, with $L = \tau, \mu$ and $\ell(') = \mu, e$, mediated by neutrino oscillations in the one-loop diagrams. Compared to the first result by Petcov:1976ff, which was obtained in the nonphysical zero momentum limit $\mathcal{P} \ll m_{\nu} \ll M_W$, we retain full d ... More
Presented by Patrick BLACKSTONE
Session: Taus
Presented by Patrick BLACKSTONE on 3 Jun 2021 at 12:00
We report on a precision measurement of the ratio $R_{\tau\mu} = BF(\Upsilon(3S)\to\tau^+\tau^-)/BF(\Upsilon(3S)\to\mu^+\mu^-)$ using data collected with the BABAR detector at the SLAC PEP-II $e^+e^-$ collider. The measurement is based on a 28 ${\mathrm{fb^-1}}$ data sample collected at a center-of-mass energy of 10.355 ${\mathrm{GeV}}/c^2$ which corresponds to a sample 122 million $\Upsilon(3S)$ ... More
Presented by Prof. Swagato BANERJEE
Session: Taus
Presented by Dr. Swagato BANERJEE on 3 Jun 2021 at 11:40
Session: Exotics
Presented by Prof. Tomasz SKWARNICKI on 31 May 2021 at 09:20
The suppressed helicity flip amplitude in baryon-antibaryon decays of $J/\psi$ is calculated within the effective field theory framework. It is shown that at the leading-order approximation this contribution is factorisable and the overlap with the hadronic final state can be described by collinear matrix elements. The obtained contribution depends on the nucleon light-cone distribution amplitu ... More
Presented by Nikolay KIVEL
Presented by Dr. Nikolay KIVEL on 4 Jun 2021 at 12:30
Session: Production
We perform a combined study of $D^+ \to K^-\pi^+\pi^+$ and $D_s \to \pi^- K^+ K^+$ decays using the naive factorization approach. The formalism allows for a description of such decays in terms of the well-known vector- and scalar- $K\pi$ form factors as well as those appearing in semileptonic $D^+ \to K^-\pi^+ \ell^+\nu$ decays. We propose a useful—yet simple—parametrization to describe the l ... More
Presented by Dr. Pablo SANCHEZ-PUERTAS
Presented by Dr. Pablo SANCHEZ-PUERTAS on 1 Jun 2021 at 12:05
Presented by Oleg MESHKOV on 3 Jun 2021 at 12:40
The ATLAS experiment has performed accurate measurements of mixing and CP violation in the neutral B mesons,and also of rare neutral B-meson decays proceeding via electroweak FCNC-suppressed processes. This talk will focus on the latest results from ATLAS, such as rate measurements of B^0_s → mu mu and B^0 → mu mu decays; and CP violation in B_s^0 —> J/psi phi decays. In the latter, the Sta ... More
Presented by Yuji ENARI
Session: Production
Presented by Zijun XU on 3 Jun 2021 at 12:40
Recent results from the ATLAS experiment on the charmonium production, B_c production and exotic heavy hadrons will be presented. The measurement of J/psi and psi(2S) differential cross sections at large transverse momentum values in proton-proton collisions at 13 TeV will be reported. The measurement of the ratios of the B_c+ and B+ production cross sections in proton-proton collisions at 8 TeV ... More
Presented by Yuji ENARI
Session: Exotics
Presented by Dr. Alessandro PILLONI on 31 May 2021 at 10:20
Session: Taus
Presented by Mr. Alejandro DE YTA HERNÁNDEZ on 3 Jun 2021 at 13:20
Presented by Prof. Bruno EL-BENNICH on 1 Jun 2021 at 12:30
I will discuss theoretical continuum approaches to bound-state calculations, strong and weak decays and effective couplings related to D mesons. The associated wave functions, light-front distribution amplitudes and hadronic matrix elements are expressions of nonperturbative QCD. After motivating their origin in QCD factorization and heavy quark effective theory, we retrace their evolution from ea ... More
Presented by Prof. Bruno EL-BENNICH
Presented by Dr. Ayan PAUL on 4 Jun 2021 at 08:30
Presented by Angelo CARBONE on 4 Jun 2021 at 07:00
Presented by Carlos RAMIREZ on 3 Jun 2021 at 13:20
The physics of CPV and oscillations in the charn sector is reviewed. Topics like the recent discover of direct CPV, the latest measurements, the respective SM predictions and the present absence of new physics in this sector.
Presented by Carlos RAMIREZ
Presented by Dr. Tatiana KHARLAMOVA on 1 Jun 2021 at 08:30
Presented by Dr. Stefan SCHACHT on 4 Jun 2021 at 09:00
Presented by Prof. Xiaoyan SHEN on 1 Jun 2021 at 07:30
Presented by Prof. Roy BRIERE on 31 May 2021 at 11:40
Presented by Jhovanny MEJIA on 31 May 2021 at 13:10
The production cross sections of open heavy-flavour hadrons can be obtained by the factorisation approach described as the convolution of the initial parton distribution functions of the incoming partons, the perturbative QCD partonic cross section, and the fragmentation functions for the hadronisation parametrised from measurements in $\mathrm{e^+e^-}$ collisions. Recent measurements of charm-ba ... More
Presented by Ms. Jinjoo SEO
Presented by Ms. Jinjoo SEO on 1 Jun 2021 at 12:20
In this contribution, we discuss the internal structure of heavy baryons and the different interpretations of the internal structure of hidden-charm pentaquarks. We present the hidden-charm pentaquarks as superpositions of meson-baryon channels coupled to a $uudc\bar{c}$ compact core by employing an interaction satisfying the heavy quark and chiral symmetries. Our model can reproduce the masses a ... More
Presented by Dr. Hugo GARCIA TECOCOATZI
Presented by Dr. Hugo GARCIA TECOCOATZI
The LHCb experiment collected the world's largest sample of charmed hadrons during LHC Run 1 and Run 2. With this data set, LHCb is currently providing the world's most precise measurements of properties and production of known charmed baryons, as well as discovering many previously unobserved states. The latest results from the LHCb Collaboration on charmed baryons are presented
Presented by Dr. Dana BOBULSKA
Presented by Dr. Dana BOBULSKA on 3 Jun 2021 at 12:20
Presented by Dr. Mikhasenko MIKHAIL on 1 Jun 2021 at 10:50
Presented by Prof. Pol GOSSIAUX on 3 Jun 2021 at 09:20
Session: Production
Presented by Mr. Antonio PALASCIANO on 3 Jun 2021 at 13:20
Experimental measurements of the charm quark showering processes are an important test for the current understanding of QCD. At the same time, in heavy-ion collisions, charm quarks represent ideal probes for studying the Quark-Gluon Plasma (QGP), being them produced in the very early stages of the collision from a hard-parton scattering. In particular, angular correlation measurements are sensib ... More
Presented by Mr. Antonio PALASCIANO
Presented by Dr. Christopher THOMAS on 2 Jun 2021 at 10:20
The measurement of charm production in hadronic collisions provides a powerful tool to understand QCD due to its creation in initial parton-parton interactions, with the heavy quark mass providing the hard scale for the process. At the LHC the measurement of the correlation of the produced $\rm c\bar{c}$ quark pairs shows sensitivity to the production mechanisms at hand. The large branching rati ... More
Presented by Mr. Horst Sebastian SCHEID
Session: Production
Presented by Mr. Horst Sebastian SCHEID on 3 Jun 2021 at 12:00
Charm quarks, created during an early stage of the heavy-ion collision via hard scattering, have a large thermalization time within quark-gluon plasma (QGP) due to their large mass. They witness the entire evolution of QGP and hence can be used as an effective probe to study the strongly interacting matter. We studied the effect of collision and gluon radiation by charm quark on its transport coef ... More
Session: In media
Presented by Ms. Adiba SHAIKH on 3 Jun 2021 at 12:00
Presented by Dr. Melissa Maria CRUZ TORRES on 2 Jun 2021 at 07:30
Session: NP in charm
Presented by Mr. Jitendra KUMAR on 4 Jun 2021 at 12:10
The Belle II experiment at the asymmetric $e^+e^-$ collider, SuperKEKB, aims to record 50 ab$^{-1}$ of data over the next decade, a factor of 50 more than Belle. During the first 1.5 years of operations, around 90 fb$^{-1}$ of data were collected. This dataset is used to measure the lifetimes of a few charm hadrons, confirming the expected performance of the Belle II detector, in particular the v ... More
Presented by Dr. Jitendra KUMAR
Presented by Frank NERLING on 31 May 2021 at 12:10
Presented by Prof. Xiao-Rui LIU on 3 Jun 2021 at 07:00
Presented by Dr. Marco Antonio BEDOLLA on 3 Jun 2021 at 13:00
Presented by Dr. Roberto MUSSA on 2 Jun 2021 at 09:50
Presented by Prof. Enrico SCOMPARIN on 3 Jun 2021 at 10:20
Results for the $\eta_c$- and $J/\Psi$-nucleus bound state energies for various nuclei are presented. These results are obtained using effective Lagrangians at the hadronic level. Essential input for the calculation, namely the medium-modified $D$ and $D^{*}$ meson masses, as well as the density distributions in nuclei, are calculated within the quark-meson coupling model. The attractive potent ... More
Presented by Dr. Javier COBOS-MARTINEZ
Session: In media
Presented by Dr. Javier COBOS-MARTINEZ on 3 Jun 2021 at 13:40
Session: Production
Charmonium production studies in hadronic collisions are a powerful tool for improving our understanding of QCD, the theory of the strong interaction. The production of the charm-quark pair can be described within perturbative QCD, whereas the evolution of this pair into a colorless bound state involves soft scale processes. In addition, multiplicity dependent studies of charmonia in both proton- ... More
Presented by Mr. Jon-Are SÆTRE
Session: Production
Presented by Mr. Jon-are SÆTRE on 1 Jun 2021 at 12:20
Presented by Dr. Geoffrey BODWIN on 2 Jun 2021 at 11:40
I will present results from the first lattice QCD+QED computations of the properties of ground-state charmonium mesons. These calculations include the effect of up, down, strange and charm quarks in the sea and cover a wide range of values of the lattice spacing enabling very accurate results in the continuum limit (with physical quark masses). We tune the charm quark's mass so that the mass of th ... More
Presented by Prof. Christine DAVIES
Presented by Prof. Christine DAVIES on 3 Jun 2021 at 12:00
A nonperturbative charm production contribution, known as intrinsic charm, has long been speculated but has never been satisfactorily proven. The SeaQuest experiment at FNAL is in an ideal kinematic region to provide evidence of $J/\psi$ production by intrinsic charm. Here, $J/\psi$ production in the SeaQuest kinematics is calculated with a combination of perturbative QCD and intrinsic charm ... More
Presented by Ramona VOGT
Session: In media
Presented by Ramona Vogt VOGT on 3 Jun 2021 at 12:40
Presented by Dr. Clara MURGUI on 3 Jun 2021 at 08:30
Presented by Dr. Patricia MAGALHAES on 1 Jun 2021 at 10:20
Presented by Prof. Alex KAGAN on 4 Jun 2021 at 07:30
LHCb has collected the world's largest sample of charmed hadrons. This sample is used to measure direct $CP$ violation in $D$ mesons and charmed baryons. New measurements from several decay modes are presented, as well as prospects for future sensitivities
Presented by Mr. Lorenzo PICA
Presented by Mr. Lorenzo PICA on 3 Jun 2021 at 12:00
Presented by Mr. Daniel Alejandro PÉREZ NAVARRO on 2 Jun 2021 at 10:50
We suggest an efective field theory based coupled-channel approach to exotic charged Z-states and demonstrate its potential at a combined analysis of the existing experimental data on the open- and hidden-flavour decays of the Upsilon(10860) resonance. As an important ingredient of the method a dispersive approach to dipion transitions to lower lying Upsilon-resonances is developed with all imagin ... More
Presented by Dr. Alexey NEFEDIEV
Presented by Dr. Alexey NEFEDIEV on 1 Jun 2021 at 13:00
Session: Production
Presented by Dr. Marco GIACALONE on 4 Jun 2021 at 12:50
Measurements of charm meson and baryon production in proton-proton collisions are an important test for perturbative QCD calculations. Measurements in p--Pb collisions provide important tools to disentagle cold nuclear matter effects (like nuclear modification of parton distribution functions). Furthermore, the study of the charm production in pp and p--Pb collisions as a function of multiplici ... More
Presented by Dr. Marco GIACALONE
We perform a global analysis of exclusive hadronic tau decays into one and two mesons using the low-energy limit of the Standard Model Effective Field Theory up to dimension six, assuming left-handed neutrinos. A controlled theoretical input on the Standard Model hadronic form factors, based on chiral symmetry, dispersion relations, data and asymptotic QCD properties, has allowed us to set bounds ... More
Presented by Dr. Sergi GONZÀLEZ-SOLÍS
Session: Taus
Presented by Dr. Sergi GONZÀLEZ-SOLIS on 4 Jun 2021 at 12:50
Session: Production
Presented by Dr. Martin HENTSCHINSKI on 3 Jun 2021 at 12:20
We investigate photo-production of vector mesons J/Psi and Upsilon measured both at HERA and LHC. We are interested in using this observable to distinguish between linear and non-linear QCD evolution at low x. The employed fits are based on non-linear Balitsky-Kovchegov evolution (Kutak-Sapeta gluon; KS) and next-to-leading order Balitsky-Fadin-Kuraev-Lipatov evolution (Hentschinski-Sabio Vera-Sal ... More
Presented by Dr. Martin HENTSCHINSKI
Presented by Prof. Eric BRAATEN on 31 May 2021 at 08:30
Presented by Dr. Xiaorong ZHOU on 1 Jun 2021 at 08:00
Session: In media
Presented by Dr. Juan TORRES-RINCÓN on 3 Jun 2021 at 13:20
We study the spectroscopy and transport properties of charmed mesons in a thermal medium by applying an effective field theory based on chiral and heavy-quark symmetries in the imaginary time formalism. Relying on unitarity constraints and self-consistency we extract the in-medium properties (masses and widths) of D and Ds mesons and their interactions with light hadrons. We report our findings on ... More
Presented by Juan TORRES-RINCON
Presented by Dr. Jolanta BRODZICKA on 4 Jun 2021 at 10:50
Presented by YuLan FAN on 3 Jun 2021 at 11:40
BESIII has collected data samples corresponding to luminosities of 2.93 fb-1 and 3.19 fb-1 at center-of-mass energies of 3.773 and 4.178 GeV, respectively. The data set collected at 3.773 GeV contains quantum-correlated D0D0bar pairs that allow to access the phase differences between amplitudes. We report the measurements of strong phase differences in D0(-bar) decays, especially for K_S/Lpi+pi- ... More
Presented by Jingzhi ZHANG
Presented by Dr. Pere MASJUAN on 2 Jun 2021 at 08:00
Presented by Dr. Matteo FAEL on 2 Jun 2021 at 13:10
Presented by Prof. Ralf RAPP on 3 Jun 2021 at 09:50
Session: In media
Presented by Peter VANDER GRIEND on 3 Jun 2021 at 13:00
Heavy quarks and their bound states are ideal probes of the quark gluon plasma formed in relativistic heavy ion collisions. Due to the hierarchy of scales of the system, the in medium dynamics can be modeled by a Langevin equation in which interactions between the medium and the heavy particle take the form of random "kicks" altering the particle's momentum. The hierarchy of scales makes the pro ... More
Presented by Peter VANDER GRIEND
Track: Charm meson and baryon spectroscopy (including exotica)
We study the nature of the new signal reported by LHCb in the $J/\psi p$ spectrum. Based on the S-matrix principles, we perform a minimum-bias analysis of the underlying reaction amplitude, focusing on the analytic properties that can be related to the microscopic origin of the Pc(4312)+ peak. By exploring several amplitude parameterizations, we find evidence for the attractive effect of the $Σ_c ... More Presented by Mr. Jorge Antonio SILVA CASTRO Presented by Mr. Jorge Antonio SILVA CASTRO on 1 Jun 2021 at 12:40 In LEP times, hadronic tau decays were the most precise input for the (leading-order) hadronic vacuum polarization piece (HVP,LO) of the muon anomalous magnetic moment ($a_\mu$). With the advent of$\Phi$- and B-factories,$e^+e^-$hadronic cross-section surpassed them, giving the most accurate input for this piece. However, since both data-driven determinations are subject to theoretical uncertai ... More Presented by Mr. Jesús MIRANDA Session: Taus Presented by Mr. Jesús MIRANDA on 4 Jun 2021 at 12:30 Presented by Prof. Aida EL-KHADRA on 2 Jun 2021 at 12:40 We study the τ−→ντ π− π0 ℓ+ ℓ− (ℓ=e, μ) decays, which are O(α^2)-suppressed with respect to the dominant di-pion tau decay channel. Both the inner-bremsstrahlung and the structure- (and model-)dependent contributions are considered. In the ℓ=e case, structure-dependent effects are O(1%) in the decay rate, yielding a clean prediction of its branching ratio, 2.3×10^(−5), ... More Presented by Mr. Jorge Luis GUTIÉRREZ SANTIAGO Session: Taus Presented by Jorge GUTIÉRREZ SANTIAGO on 3 Jun 2021 at 12:40 Presented by Dr. Fernando SERNA on 4 Jun 2021 at 12:35 The ladder kernel of the Bethe-Salpeter equation is amended by introducing a different flavor dependence of the dressing functions in the heavy-quark sector. Compared with earlier work this allows for the simultaneous calculation of the mass spectrum and leptonic decay constants of light pseudoscalar mesons, the$D_u$,$D_s$,$B_u$,$B_s$and$B_c$mesons and the heavy quarkonia$\eta_c$and$\ ... More
Presented by Dr. Fernando SERNA
Presented by Prof. Shuangshi FANG on 2 Jun 2021 at 07:00
In the heavy-quark limit, the two heavy quarks in a doubly heavy baryon or a doubly heavy tetraquark are bound by their color-Coulomb potential into a compact diquark. The doubly heavy hadrons are related by the approximate heavy-quark--diquark symmetry of QCD to the heavy hadrons obtained by replacing the heavy diquark by a heavy antiquark. Effective field theories can be used to expand the masse ... More
Presented by Mr. Abhishek MOHAPATRA
Presented by Mr. Abhishek MOHAPATRA on 3 Jun 2021 at 12:40
Session: Production
Presented by Dr. Renu BALA on 4 Jun 2021 at 12:10
In this contribution, the nuclear modification factor (RAA) and the elliptic flow (v2) of open heavy-flavour hadrons via their hadronic and semileptonic decays to electrons at mid-rapidity and to muons at forward rapidity in heavy-ion collisions will be presented. The measurements of the production of leptons from heavy-flavour hadron decays and the modification of their spectra in different colli ... More
Presented by Dr. Renu BALA
We study the transitions between the different color states of a static quark-antiquark pair, singlet and octet, in a thermal medium. This is done non-perturbatively exploiting the infinite mass limit of QCD. This study is interesting because it can be used for future developments within the framework of Effective Field Theories (EFTs) and because it can be combined with other techniques, like ... More
Presented by Dr. Miguel Ángel ESCOBEDO ESPINOSA
Session: In media
Presented by Dr. Miguel Ángel ESCOBEDO on 3 Jun 2021 at 12:20
LHCb has collected the world's largest sample of charmed hadrons. This sample is used to measure $D^0 -\overline{D}^0$ mixing parameters and to search for $CP$ violation in mixing and interference. New measurements from several decay modes are presented, as well as prospects for future sensitivities.
Presented by Dr. Guillaume PIETRZYK
Presented by Dr. Guillaume PIETRZYK on 3 Jun 2021 at 13:00
The experimental information accumulated by the BABAR, Belle and LHCb experiments have shown disagreement on the measurements of the ratios $R(D)$ and $R(D^{*})$, compared with the SM predictions. In addition, the $D^\ast$ longitudinal polarization $F_L(D^\ast)$ related with the channel $B \to D^\ast \tau \bar{\nu}_\tau$ observed by the Belle Collaboration and the ratio $R(J/\psi)$ measured by the ... More
Presented by Dr. Nestor QUINTERO POVEDA
Session: NP in charm
Presented by Dr. Nestor QUINTERO POVEDA on 4 Jun 2021 at 13:10
We analyze the τ-→(Kπ)-ντ decays within an effective field theory description of heavy new physics (NP) modifying the SM left-handed weak charged current and include refined SM input for the participant meson form factors exploiting chiral symmetry, dispersion relations and (lattice) data. We include the leading dimension six operators and work at linear order in the effective couplings. Wit ... More
Presented by Mr. Javier RENDON
Session: Taus
Presented by Mr. Javier RENDON on 4 Jun 2021 at 13:30
Rare $\vert \Delta c \vert=\vert \Delta u \vert=1$ processes complement flavor searches in the down-sector in a unique way. Semileptonic FCNC decays of charmed hadrons offer a large set of clean null test observables, such as CP-asymmetries, lepton-universality ratios, missing energy modes, lepton flavor violating modes and angular observables. In these observables any signal cleanly indicates Phy ... More
Presented by Mr. Marcel GOLZ
Session: NP in charm
Presented by Mr. Marcel GOLZ on 4 Jun 2021 at 12:30
Presented by Mr. Hongrong QI
psi(2S) provides good opportunities for the study of chi_cJ, eta_c, and h_c decays. These studies can be used to verify QCD based models, which provide predictions for the decay mechanism. With the world's largest sample of 4.48*10^8, progress on the charmonium decays has been made. In the talk, we report the new results, such as the first measurement of the branching ratio of chi_c1,2 to mu+ mu- ... More
Presented by Jingzhi ZHANG
Presented by Barbara TRZECIAK on 3 Jun 2021 at 10:50
Presented by Dr. Marianna FONTANA on 3 Jun 2021 at 08:00
Presented by Prof. Jonas RADEMACKER on 4 Jun 2021 at 11:20
Session: Production
Presented by Prof. Mikhail BARABANOV
We compute masses of open and hidden charmed mesons in the framework of the extended Linear Sigma Model (eLSM) with (pseudo-)scalar and (axial-) vector mesons. Open charmed mesons masses turn out to be in quantitative agreement with experimental data. Whereas the masses of hidden charmed mesons, with the exception of $J/\psi$, are underpredicted by about $10$%. We calculate the (OZI-dominant) stro ... More
Presented by Dr. Walaa ESHRAIM
Session: Production
Session: Production
Presented by Dr. ESHRAIM WALAA on 4 Jun 2021 at 13:10
Session: Production
Presented by Dr. Emmanuel ORTIZ-PACHECO on 4 Jun 2021 at 13:30
Presented by Andrzej KUPSC on 1 Jun 2021 at 09:50
The dependence of the production of the $X(3872)$ meson on the hadron multiplicity in $pp$ collisions has been used as evidence against $X$ being a charm-meson molecule. The argument is based in part on the incorrect assumption that the cross section for the breakup of $X$ by scattering with comovers can be approximated by a geometric cross section inversely proportional to the binding energy of $... More Presented by Mr. Kevin INGLES Session: Production Presented by Mr. Kevin INGLES on 1 Jun 2021 at 12:40 Presented by Prof. Khodjamirian ALEXANDER on 4 Jun 2021 at 08:00 Session: Production Presented by Krista SMITH on 1 Jun 2021 at 13:00 Suppression of the J/ψ nuclear modification factor has long been considered a signature of final state effects in large collision systems. In small systems, nuclear modification was assumed to be due to initial state cold nuclear matter effects, until the observation of strong differential suppression of the ψ(2S) state in p+A collisions suggested the presence of final state effects. Here we pre ... More Presented by Krista SMITH One of the best ways to understand hadronization in QCD is to study the production of quarkonium. However, the production mechanism of quarkonium is still uncertain. Spin-related measurements like the polarization are strong tests of production models. In this talk I will summarize recent results of quarkonium production and polarization in elementary collisions, including the results from NRQCD ... More Presented by Vincent CHEUNG Session: Production Presented by Vincent CHEUNG on 4 Jun 2021 at 12:30 Session: Production Presented by Dr. Vincent CHEUNG Presented by Prof. Antonio VAIRO on 2 Jun 2021 at 12:10 Presented by Dr. Isabella GARZIA on 4 Jun 2021 at 12:50 In this talk we present the latest results on radiative and rare/forbidden decays for D and D_s mesons from the BESIII experiment based on 2.92 fb$^{-ˆ’1}$and 3.19 fb$^{-1}$data samples taken at the center-of-mass energies 3.773 and 4.178 GeV, respectively. With the 4.178 GeV data, searches for the rare decay$D^+_S\to p\bar{p}e^+\nu_e$and rare radiative leptonic decay$D_S^+\to\gamma e^+\nu ... More
Presented by Jingzhi ZHANG
Presented by Mr. Nico ADOLPH on 4 Jun 2021 at 13:30
We compute radiative three-body decays of charmed mesons $D \to P P \gamma$ , $P=\pi, K$, in leading order QCDF, HH$\chi$PT and the soft photon approximation. We work out decay distributions and asymmetries in the standard model and with new physics in the electromagnetic dipole operators. The forward-backward asymmetry is suitable to probe the QCD frameworks, in particular the $s$-channel depende ... More
We report the observation of the rare charm decay $D^0 \to K^-\pi^+e^+e^-$, a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type $D^0 \rightarrow h^- h^{'-} \ell^+ \ell^{'+}$, and $D^0 \rightarrow h^- h^{'+} \ell^+ \ell^{'-}$, and a search for seven lepton-number-violating decays of the type $D^{0}\rightarrow X^{0} e^{\pm} \mu^{\mp}$, where $... More Presented by Dr. David N. BROWN Session: NP in charm Presented by Dr. David BROWN on 4 Jun 2021 at 12:50 Presented by Prof. Svetlana FAJFER on 3 Jun 2021 at 07:30 The Belle II experiment has accumulated data corresponding to 89.99 fb-1 integrated luminosity in the past 2 years, and is performing very good. Waiting that the full planned data set will be recorded (50 ab-1), which will allow search for rare processes and will have a tremendous impact in the spectroscopy field, the Phase 3 data set allows to already perform analysis with high precision. We pres ... More Presented by Dr. Youngmin YOOK Session: Production Presented by Dr. Youngmin YOOK on 3 Jun 2021 at 11:40 Presented by Sean DOBBS on 31 May 2021 at 12:40 Presented by Dr. Longke LI on 1 Jun 2021 at 07:00 Session: Exotics Presented by Prof. Alexis POMPILI on 31 May 2021 at 10:50 A naive application of the heavy quark expansion (HQE) yields theory estimates for the decay rate of neutral$D$mesons that are four orders of magnitude below the experimental determination. It is well known that this huge suppression results from severe GIM cancellations. We find that this mismatch can be solved by individually choosing the renormalisation scale of the different internal ... More Presented by Mr. Christos VLAHOS Presented by Mr. Christos VLAHOS on 3 Jun 2021 at 12:20 Presented by Dr. Aleksey RUSOV on 4 Jun 2021 at 13:00 In this talk, I plan to present preliminary results of updated SM predictions for charm-meson lifetimes, their ratios and also the semileptonic decay widths, based on the Heavy Quark Expansion (HQE). In addition to the known contributions, for the first time we include the dimension-six Darwin term for non-leptonic charm decays and the first determinations of the dimension-six Bag paramet ... More Presented by Dr. Aleksey RUSOV Presented by Prof. Vorobiev VITALY on 1 Jun 2021 at 09:20 Many models of dark matter and hidden sectors predict new particles with masses below the electroweak scale. Low-energy electron-positron colliders such as BABAR are ideally suited to discover these hidden-sector particles. We present a recent search for prompt and long-lived hidden scalars produced in association with tau leptons and decaying into a lepton pair. This search is sensitive to viable ... More Presented by Dr. Steven ROBERTSON Session: Taus Presented by Dr. Robertson STEVEN on 3 Jun 2021 at 12:20 Presented by Dr. Huijing LI on 4 Jun 2021 at 12:10 BESIII has collected data samples corresponding to luminosities of 2.93 fb-1 and 3.19 fb-1 at center-of-mass energies of 3.773 and 4.178, respectively. We report recent measurements that include the decays D(s)+ -> l+v (l=mu, tau), D0(+) -> K-bar(pi)l+v (l=e,mu), D0(+) -> a0(980)e+v, D+->K1(1270)e+nu, D(s)+ -> eta(')e+nu, Ds+ -> K(*0)enu, Ds+ -> phi enu,. The first searches for Ds+ -> gamma e+nu a ... More Presented by Jingzhi ZHANG We study the expected sensitivity at Belle and Belle II for four-body τ∓→X±l∓l∓ντ decays where l=e or μ and X=π, K, ρ and K∗ mesons. These decay processes violate the total lepton number (|ΔL|=2 ) and they can be induced by the exchange of Majorana neutrinos. In particular, we consider lifetimes in the accessible ranges of τN = 5, 100 ps and extract the limits on |VℓN|2 withou ... More Presented by Dr. Pedro PODESTA Session: Taus Presented by Mr. David RODRÍGUEZ PÉREZ on 3 Jun 2021 at 13:00 Session: Exotics Presented by Prof. Feng-Kun GUO on 31 May 2021 at 09:50 The BES III detector at Beijing Electron-Positron Collider has collected the world’s largest data sets. In this talk I will report recent results on the baryon pair production in Charmonium(-like) and in the e+e− annihilation at BESIII. Presented by Dr. Xiongfei WANG Session: Production Presented by Dr. Xiongfei WANG on 1 Jun 2021 at 11:40 We study the processes γγ → η ′ K + K − , η ′ π + π − , and ηπ + π − using a data sample of 519 f b −1 recorded with the BaBar detector operating at the SLAC PEP-II asymmetric-energy e + e − collider at center-of-mass energies at and near the Υ(nS) (n = 2, 3, 4) resonances. This is the first observation of the decay η c → η ′ K + K − and we measure the branchin ... More Presented by Prof. Antimo PALANO Presented by Prof. Antimo PALANO on 1 Jun 2021 at 11:40 Session: Production The data on tau neutrino is very scarce, only a few experiments have detected its interactions. At FNAL beam dump experiment DONUT, tau neutrino interaction cross-section was directly measured with a large systematical (~50%) and statistical (~30%) errors. The main source of systematical error is due to a poor knowledge of the tau neutrino flux. The effective way for tau neutrino production is the ... More Presented by Collaboration DSTAU Session: Taus Presented by Prof. Ali Murat GULER on 4 Jun 2021 at 13:10 Session: Production Session: Production Session: Taus Presented by Prof. Alberto LUSIANI on 4 Jun 2021 at 10:20 Presented by Emilie PASSEMAR on 4 Jun 2021 at 09:50 The Belle II experiment is a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric e+e− collider. The design luminosity of the machine is 8 × 1035 cm−2s−1 and the Belle II experiment aims to record 50 ab−1 of data, a factor of 50 more than its predecessor. From February to July 2018, the machine has completed a commissioning run and main operation o ... More Presented by Dr. Thomas KRAETZSCHMAR Session: Taus Presented by Mr. Thomas KRAETZSCHMAR on 4 Jun 2021 at 12:10 Based on the Generalized Quantum Electrodynamics expression for the Podolsky propagator, which preserves gauge invariance for massive photons, we propose a model for the massive gluon propagator that reproduces well-known features of established strong-interaction models in the framework of the Dyson-Schwinger equation. By adjusting the Podolsky mass and the coupling strength we thus construct a m ... More Presented by Prof. Eduardo ROJAS PEÑA Presented by Prof. Eduardo ROJAS PEÑA on 4 Jun 2021 at 13:25 Session: NP in charm Presented by Mr. Marxil SÁNCHEZ GARCÍA on 4 Jun 2021 at 13:30 The$D_s$semileptonic decays provides an ideal scenario in the charm sector to search for Lepton number violation (LNV), Lepton flavor universality (LFU) tests and new contributions in Flavor changing neutral currents (FCNC) modes. In this work, we first describe the long distance (LD) contributions in the$D_{s} \rightarrow \pi l^{+} l^{-}$decay, a non-FCNC mode usually employed as normalizati ... More Presented by Mr. Marxil SÁNCHEZ Presented by Mrs. Raquel MOLINA PERALTA on 1 Jun 2021 at 12:55 In a recent paper [1], the BESIII collaboration reported the so-called first observation of pure$W$-annihilation decays$D^+_s \to a^+_0(980) \pi^0$and$D_s^+ \to a^0_0(980)\pi^+$. The measured absolute branching fractions are, however, puzzlingly larger than those of other measured pure$W$-annihilation decays by at least one order of magnitude. In addition, the relative phase between the two d ... More Presented by Dr. Raquel MOLINA PERALTA The SHiP collaboration proposes a general purpose fixed-target experiment to search for hidden particles at the new beam-dump facility at CERN SPS. For the interpretation of these searches a precise knowledge of the differential charm production cross-section in a thick target, including the cascade production, is essential. To obtain this parameter, several dedicated measurements at CERN SPS have ... More Presented by Mr. Nikolaus OWTSCHARENKO Session: Production Presented by Mr. Nikolaus OWTSCHARENKO on 3 Jun 2021 at 13:00 If the X(3872) is a weakly bound charm-meson molecule, it can be produced by the creation of$D^∗ \bar D^∗$at short distances followed by the rescattering of the charm mesons into X(3872) and a photon or a pion through a triangle loop. A triangle singularity produces narrow peak in the reaction rate in production of X(3872). The observation of this peak would provide strong evidence in suppor ... More Presented by Ms. Liping HE Session: Production Presented by Ms. Liping HE on 1 Jun 2021 at 12:00 Presented by Prof. Lisheng GENG The recent LHCb discovery of three pentaquark states may usher in a new ear in our understanding of the low energy strong interaction. These states might be part of a first complete multiplet composed of seven hadrons of molecular nature. At least this is what emerges from a leading order effective field theory using only data and heavy quark spin symmetry as constrains [1]. In addition, we will s ... More Presented by Prof. Lisheng GENG The$X(3872)$, whose mass coincides with the$D^0\bar{D}^{*0}$threshold, is the most extended hadron object. Since its discovery in 2003, debates have never stopped regarding its internal structure. We propose a new object, the X atom, which is the$D^\pm D^{*\mp}$composite system with positive charge parity and a mass of$(3879.89\pm0.07)$~MeV, formed mainly due to the Coulomb force. We show ... More Presented by Mr. Zhenhua ZHANG Presented by Mr. ZHANG ZHENHUA on 1 Jun 2021 at 12:00 From 2011, BESIII has taken about 20 fb^-1 data samples at center of mass energies from 3.8 to 4.6 GeV, containing 21 energy points with luminosity larger than 400 pb^-1. This makes the study of vector states Y, charged states Z, X states, as well as the connections between them through transition processes possible. Using these data samples, new information about X(3872) decays, Y states from ope ... More Presented by Jingzhi ZHANG Presented by Dr. Weimin SONG on 1 Jun 2021 at 11:40 Recently, BESIII reported observation of the structure at the kinematical threshold in the$D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0}$mass distribution, which is interpreted as a tetraquark candidate, called$Z_{cs}(3985)^{-}\$. This is the first candidate for a tetraquark meson containing hidden-charm with non-zero strangeness. BESIII has been devoting on the studies on the nonstrange charmoniumlike Zc sta ... More