Search

Quark mass determinations based on lattice QCD simulations have continued to make strides in recent years. Here I review that progress with a focus on developments computing the charm (and bottom) quark masses since the 2015 edition of CHARM. These advances have resulted in groups now quoting (sub-)percent-level precision for these quantities, and, importantly, using a variety of techniques subject to differing systematic uncertainties. Improvements to quantify the effects of QED are also now being included. I will highlight three of the strategies being used to determine $m_c$ at this level of precision.

In this talk, I present the potential physics program of the super $\tau$-charm factory (STCF). The STCF is an electron-positron collider with a center-of-mass energy ranging from 2 to 7 GeV and an instantaneous luminosity greater than $0.5\times 10^{35}$ cm$^{-2}$s$^{-1}$. This energy region corresponds to the transition between non-perturbative quantum chromodynamics (QCD) and perturbative QCD. Hence, a large variety of topics in elementary particle physics can be pursued at STCF, including exploring QCD and hadron spectroscopy, precise measurement of electroweak interactions and flavor physics studies as well as searches for the new physics beyond the standard model.

The Belle II experiment started collecting data in summer 2018 and since then more than 176 fb$^{-1}$ of integrated luminosity has been collected. With the current sample size, charm measurements are focused mostly on early reconstruction and studies of detector performance. In this proceeding, we present the current status and prospects of the charm measurements with the target luminosity of 50 ab$^{-1}$ at Belle II. In particular, the $D^{0}$ and $D^{+}$ lifetime study, time-integrated charge-parity ($CP$) asymmetries, $D^{0}-\bar{D}^{0}$ mixing and decay-time-dependent $CP$ violation (CPV) measurements are discussed.

In the present work we estimate the orbital contribution to the photoproduction of the ground state pentaquarks, described as compact $qqqQ\bar{Q}$ configurations with $J^P=3/2^-$ in the framework of the harmonic oscillator quark model. The photocouplings $P_c(uudc\bar{c}) \rightarrow p+\gamma$ are found to be highly suppressed due to the large value of the photon momentum.

In this contribution, the latest measurements of $\Lambda_\mathrm{c}^+$, $\Xi_\mathrm{c}^{0,+}$, $\Sigma_\mathrm{c}^{0,++}$, and the first measurement of $\Omega_\mathrm{c}^0$ baryons performed with the ALICE detector at midrapidity in pp collisions at $\sqrt{s}=5.02$ and $13\,\rm TeV$ are presented. In addition, the \Lc measurement down to $p_\mathrm{T}=0$ in p--Pb collisions will be discussed. Finally, the first measurements of the total charm cross section per unit of rapidity and the fragmentation fractions at midrapidity in pp collisions at the LHC including the charm baryons are discussed.

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 searching for many previously unobserved states. The latest results on the charmed baryons described in this document include the lifetime measurement of the $\it{\Omega}_{c}^{\mathrm{0}}$ and $\it{\Xi}_{c}^{\mathrm{0}}$ baryons that are produced directly from proton-proton collisions and reconstructed in the $p K^{-} K^{-} \pi^{+}$ final state. The $\it{\Omega}_{c}^{\mathrm{0}}$ lifetime is measured to be $276.5 \pm 13.4 \mathrm{\,(stat)} \pm 4.4 \mathrm{\,(syst)} \pm 0.7 (\it{D}^{\mathrm{0}}) \mathrm{ \,fs}$ and the $\it{\Xi}_{c}^{\mathrm{0}}$ lifetime to be $148.0 \pm 2.3 \mathrm{\,(stat)} \pm 2.2 \mathrm{\,(syst)} \pm 0.2 (\it{D}^{\mathrm{0}}) \mathrm{ \,fs}$. Both results are consistent with the previous LHCb measurement based on semileptonic decays of $b$-hadrons. The latest results on the charm baryons from the LHCb collaboration also include searches for the $\it{\Xi}_{cc}^{+}$ baryon in the $\it{\Xi}_{cc}^{+} \rightarrow \it{\Xi}_{c}^{+} \pi^{-} \pi^{+}$ decay, the first search for the $\it{\Omega}_{cc}^{+}$ baryon in the $\it{\Omega}_{cc}^{+} \rightarrow \it{\Xi}_{c}^{+} K^{-} \pi^{+}$ decay, and the searches for the $\it{\Xi}_{bc}^{\mathrm{0}}$ and $\it{\Omega}_{bc}^{\mathrm{0}}$ baryons in the $\it{\Lambda}_{c}^{+} \pi^{-}$ and $\it{\Xi}_{c}^{+} \pi^{-}$ final states. No significant signals are found for neither of these decays, therefore upper limits are set on the ratio of production cross-sections times the ratio of branching fractions with respect to their normalisation decay.

A collection of different studies about bound states of hadrons composed of charm quarks is presented. These studies used a symmetry preserving vector-vector contact interaction model within the framework of Schwinger-Dyson and Bethe-Salpeter equations. Despite its limitations, the contact interaction model offers a simple-to-implement alternative to perform exploratory studies of QCD, obtaining an spectrum of charmed hadrons in agreement within 2% when they are compared with experimental data. In particular, the spectrum of charm and beauty mesons is presented.

The recent results about charm jet and correlation measurements by the ALICE experiment are presented in this contribution. The measurements of the $\mathrm{D}^0$ parallel jet momentum fraction in pp collisions at $\sqrt{s}=5.02$ and $13$ TeV are shown and compared with Monte Carlo model predictions. $\mathrm{\Lambda_c}$-tagged jets in pp collisions at $\sqrt{s}=13$ TeV, including their jet momentum fraction measurements, are shown. Measurements of the radial displacement in $\mathrm{D^0}$ and $\mathrm{\Lambda_c}$ jets in pp collisions at $\sqrt{s}=13$ TeV are also illustrated. The nuclear modification factor of jets tagged with electrons from heavy-flavour hadron decays in p--Pb collisions at $\sqrt{s}=5.02$ TeV is then discussed. Finally, the new results about azimuthal correlations between heavy-flavour decay electrons and hadrons in pp collisions at $\sqrt{s}=$5.02 TeV are introduced.

Studies on the weak decays of charmed baryons provide useful information for understanding the interplay of weak and strong interactions in the charm sector. In 2014, the BESIII experiment accumulated a data set of 567 pb$^{-1}$ at the center-of-mass energy of $\sqrt{s}$=4.6 GeV, an energy point slightly above the $\Lambda^+_c \bar{\Lambda}^-_c$ mass. This is the world first threshold data of the $\Lambda^+_c$ baryon and provides systematical measurements on the production and decay properties of the $\Lambda^+_c$. So far BESIII has published 17 papers of about 30 reaction channels based on the data set taken at 4.6 GeV. In this proceeding, I summarize the BESIII results on the $\Lambda^+_c$ decays in the recent three years. In addition, some prospects on the future programme of charmed baryons are discussed.

I review Standard Model contributions to 𝑐 → 𝑢𝑙+𝑙− and 𝑐 → 𝑢 invisibles transitions in the exclu- sive rare 𝐷 → 𝑃𝑙+𝑙−, 𝐷 → 𝑃1𝑃2𝑙+𝑙−, 𝐷 → missing energy, and 𝐷 → 𝑃 missing energy decays. Then, I discuss New Physics effects in these processes, using low-energy existing constraints, as the experimental bound on B(𝐷0 → 𝜇+𝜇−), 𝐷0 − 𝐷 0 oscillations. I compare them with the contributions allowed by the experimental limits on the rates for 𝐷 → 𝑃𝑙+𝑙−, 𝐷 → 𝑃1𝑃2𝑙+𝑙−, and 𝐷 → missing energy decays.

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. For this purpose, a dedicated measurement at CERN SPS has been proposed. An optimization run has been performed with 400 GeV/c protons interacting with a thick target of up to 1.6 nuclear interaction lengths. The production and decay of charmed hadrons in the target is detected by emulsion films arranged in a moving brick containing emulsion cloud chambers. A magnetic spectrometer using silicon pixel, scintillating fiber and drift-tube detectors is built to measure charge and momentum of the decay daughters and is followed by an RPC muon tagger. We report on the experiment design, track matching and first results of the optimization run.

We review the recent results obtained by the KEDR experiment in the charmonium energy range. They include the measurements of $J/\psi$ meson total and partial widths and exclusive branching fractions, study of $D^+$ and $D^0$ meson masses and R between 1.8 and 7.0 GeV.

In this paper we present two studies made by the CMS Collaboration. The first is the CMS measurement of prompt $D^{*+}$, $D^{+}$ and $D^{0}$ production cross sections at $\sqrt{s}=$ 13 TeV. The second one corresponds to the first observation of the $B_s^0 \to X(3872) \phi$ decay and the measurement of its branching fraction. The value obtained for the $B_s^0$ branching fraction is consistent with that of $B^0$ but smaller by a factor of two when compared with the same measurement for $B^+$, indicating the difference in the production dynamics of X(3872) in $B_s^0$ and $B^+$ decays.

Energy loss of quarks in the hot and dense medium has been studied for decades. Both the experimental and theoretical efforts have hinted that the energy loss is quark mass dependent. Although experiments at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) have found that the electrons from heavy quarks are less or similarly suppressed compared to the light hadrons, the mass ordering of the suppression between charm and bottom quarks is not yet clear due to large experimental uncertainties. We have fully exploited the events recorded at mid-rapidity in Au+Au collisions at center-of-mass energy of 200 GeV by the PHENIX experiment at RHIC to study the invariant yield of electrons from open heavy flavors. Latest results on the nuclear modification factors for charm and bottom separated heavy flavor electrons are reviewed in this proceeding. The implications of these results on the understanding of the quark mass and medium size dependence of the energy loss are also discussed.

In this overview contribution we introduce the most recent results in high-multiplicity $pp$ and heavy ion collisions obtained by the LHCb experiment, detector developments and plans for the future heavy ion program. Some of the highlights include the study of double charm production, nuclear modification of B-hadrons, quarkonia and Z-bosons in $p$Pb and the suppression of prompt X(3872) hadrons in high multiplicity $pp$ events. On the detector side, we bring to attention the preparation for the upcoming Run III in LHC and the fixed target program.

Because of their large masses, the interactions of heavy quarks with the quark-gluon plasma (QGP) may be different from those of light quarks and hence can provide essential inputs in understanding the QGP. With strange quark yields being enhanced in the presence of a QGP, the production of $D_{s}^{+}$ is expected to be enhanced if recombination plays an important role in the hadronization process. Furthermore, studies of the lightest charm baryon, $\Lambda_{c}^{+}$, can provide further information to charm quark hadronization. Models involving quark coalescence predict a large enhancement of $\Lambda_{c}^{+}$ production in PbPb collisions compared to pp collisions. The $\Lambda_{c}^{+}$ and $D_{s}$ production in both pp and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been measured in the CMS experiment. Results of $\Lambda_{c}^{+}$ and $D_{s}$ differential cross-sections, and the ratios of these two yields over those for $D^{0}$ in pp and PbPb collisions are presented.

The ALICE Collaboration at the LHC aims at investigating the properties of hot and dense QCD matter, the quark-gluon plasma (QGP), created in ultra-relativistic heavy-ion collisions. Heavy quarks are created in initial hard scattering process, therefore they are effective probes of the evolution of the QGP. Since beauty quarks are four times heavier than charm quarks, we can get an insight into the in-medium mass dependent energy loss by comparing beauty with charm. In ALICE, beauty production can be studied via semi-electronic decays of beauty hadrons. The yield of electrons coming from open beauty-hadron decays is obtained by fitting the impact parameter distribution with templates of different electron sources. In this contribution, the measurements of electrons from beauty-hadron decays in Pb-Pb collisions at $\sqrt{\it{s}_{\rm{NN}}}$ = 5.02 TeV are presented.

These proceedings summarize the LHCb measurements of charm- and beauty-hadron production in pPb collisions. The studies are made down to very low-pT of the observed heavy-flavor hadrons using fully reconstructed decays. Nuclear matter effects are quantified via nuclear modification factors and forward-backward production ratios, suggesting a strong suppression for the forward rapidity and no suppression for the backward rapidity. The results help to constrain nuclear parton distribution distribution down to Bjorken-x∼ 10^−5. The charm pair production is first measured in pPb data, which comfirms the enhancement of double parton scattering in pPb collisons. These data provide important inputs to understand the Quark-Gluon Plasma formed in heavy-nucleus collisions.

Theoretical predictions of the prompt atmospheric neutrino flux have large uncertainties associated with charm hadron production, by far the dominant source of prompt neutrinos in the atmosphere. The flux of cosmic rays, with its steeply falling energy spectrum, weights the forward production of charm in the evaluation of the atmospheric neutrino flux at high energies. The current LHCb experiment at CERN constrains charm production in kinematic regions relevant to the prompt atmospheric neutrino flux. The proposed Forward Physics Facility has additional capabilities to detect neutrino fluxes from forward charm production at the LHC. We discuss the implications of the current and planned experiments on the development of theoretical predictions of the high energy atmospheric neutrino flux., Comment: 8 pages, 6 figures. Proceedings of the 37th International Cosmic Ray Conference (ICRC 2021)

International audience; Recent charm meson spectroscopy results from amplitude analysis of $B$ decays to open charm states at LHCb are reported. The amplitude analyses technique is used in the description of $~{B^{-} \to D^{*+} \pi^{-} \pi^{-}}$ decays and a study of the excited charm meson spectra in the $D^{*+} \pi^{-}$ system is performed.

Studies of the production of heavy-flavour baryons are of prominent importance to investigate hadronization mechanisms at the LHC, in particular through the study of the evolution of the baryon-over-meson production ratio. Measurements performed in pp and p--Pb collisions at the LHC have revealed unexpected features, qualitatively similar to what was observed in heavy-ion collisions and, in the charm sector, not in line with the expectations based on previous measurements from $\rm e^+e^-$ colliders and in ep collisions. These results suggest that charmed baryon formation might not be universal and that the baryon-over-meson ratio depends on the collision system or multiplicity. A review of ALICE measurements of charmed baryons, including $\rm \Lambda_c^+/D^0$ as a function of charged-particle multiplicity in pp, p--Pb and Pb--Pb collisions, $\rm \Sigma_c^{0, +, ++}/D^0$ and $\rm \Xi_c^{0, +}/D^0$ as a function of $p_{\rm T}$ in pp collisions and $\rm \Gamma(\Xi_c^0\rightarrow\Xi^-e^+\nu_e)/\Gamma(\Xi_c^0\rightarrow\Xi^-\pi^+)$, will be presented. Comparison to phenomenological models will be also discussed. Emphasis will be given to the discussion of the impact of these studies on the understanding of hadronization processes., Comment: Proceedings of 40th International Conference on High Energy physics, July 28 - August 6, 2020. 6 pages, 3 figures

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. In addition, data sample with a luminosity of about 3 fb^(-1) at center-of-mass energies between 4.19 and 4.23 GeV are used to study D_s decays in some analyses. We report recent measurements that include the decays D_((s))^+→l^+ ν (l=μ,τ), D^0→K^- μ^+ ν_μ, D^+→η⁄(ωμ^+ ν_μ,) D^0(+) →ππe^+ ν_e, D^+→K_1 (1270)^0 e^+ ν_e, D_s^+→η^((')) e^+ ν_e and D_s^+→K^((*)) e^+ ν_e. From these analyses, the decay constants f_(D_((s)) ), the semileptonic form factors f_+^P (0) (P=K, η^((')), the CKM matrix elements |V_(cd(s)) | are determined precisely. These results can verify the LQCD calculations of f_(D_((s)) ), f_+^P (0) and the CKM matrix unitarity. Precision tests of lepton-flavor universality are also made via these decays.

The BESIII experiment has collected $e^+e^-$ collision data samples corresponding to integrated luminosities of $2.93~\rm{fb^{-1}}$ and $3.19~\rm{fb^{-1}}$ at center-of-mass energies of $3.773~\rm{GeV}$ and $4.178~\rm{GeV}$, respectively. We report the measurements of strong phase differences in $D^{0}$ decays, including $K_{S/L}\pi^{+}\pi^{-}$ and $K_{S/L}K^{+}K^{-}$, which can reduce the systematic uncertainty of $\gamma/\phi_{3}$ measurement at LHCb and Belle II. In addition, we report the amplitude analyses and the measurements of the absolute branching fractions of $D^{+}$, $D^{0}$, and $D_{s}$ decays.

This talk presents our recent results [1] on nonfactorizable charm-loop contributions to the amplitudes of rare exclusive $B$-decays induced by flavour-changing neutral currents (FCNC). We show that such contributions induced by a soft-gluon emission from the charm-quark loop may be expressed via three-particle quark-antiquark-gluon distribution amplitude (3DA) of the $B$-meson, $\langle 0|\bar q(x)G_{\mu\nu}(y)b(0)|B(p)\rangle$, and the knowledge of the full functional dependence of the latter quantity on the variable $(x-y)^2$ is necessary for a proper summation of potentially large terms $O\left(\left(\Lambda_{QCD}m_b/m_c^2\right)^n\right)$ in the amplitudes of FCNC $B$-decays.

The study of heavy-flavour (charm and beauty) production is important to understand the properties of the Quark-Gluon Plasma (QGP) formed in ultra-relativistic heavy-ion collisions, since heavy quarks are produced in the initial stages of the collisions and subsequently interact with the medium throughout its evolution. In the QGP, strange quarks are expected to be abundantly produced and may recombine with charm quarks leading to an enhancement of the nuclear modification factor ($R_{\rm AA}$) of ${\rm D}_{\rm s}^{+}$ mesons compared to that of other charmed meson states at low and intermediate $p_{\rm T}$. The measurement of elliptic flow ($v_{2}$) of ${\rm D}_{\rm s}^{+}$ mesons is useful to determine the degree of thermalisation of charm quarks in the collective expansion of the QGP. In addition, charm quarks could recombine with light di-quark states in the medium, which would lead to an enhancement of the $\Lambda_{\rm c}^{+}/{\rm D}^{0}$ baryon-to-meson ratio as compared to that in pp collisions. Precise measurements of these particle species in Pb-Pb collisions, therefore, give a deeper insight into the hadronisation mechanisms that heavy quarks undergo in the strongly-interacting medium. In this contribution, the latest results measured with ALICE for ${\rm D}_{\rm s}^{+}$-meson and $\Lambda_{\rm c}^{+}$-baryon production in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV, using data from Run 2 of the LHC are discussed., Comment: Proceedings of EPS-HEP Conference 2019. 6 pages, 4 figures

Charge-parity ($\textit{CP}$) violation is well established in the kaon and beauty sectors and was observed in charm decays for the first time in 2019 by the LHCb experiment at the level of $5.3\sigma$. The LHCb detector has collected billions of $D^0$ decays, making it an ideal laboratory to study charm decays. This document covers four recent analyses that explore various sources of $\textit{CP}$ violation in the charm sector.

Heavy quarks are useful probes to investigate the properties of the Quark-Gluon Plasma (QGP) produced in heavy-ion collisions at the LHC, since they are produced in initial hard scattering processes. To single out the signals that are characteristic of the QGP, it is nevertheless crucial to understand the primordial heavy-quark production in vacuum, and to disentangle hot from cold nuclear matter effects. Moreover, observations of collective effects in high-multiplicity pp and p-Pb collisions show surprising similarities with those in heavy-ion collisions. Heavy-flavour production in such collisions could give further insight into the underlying processes. The heavy-flavour production can be studied with $\rm e^{+}e^{-}$ pairs from correlated semileptonic decays of heavy-flavour hadrons. Compared to single heavy-flavour measurements, the dielectron yield contains information about the initial kinematical correlations between the charm and anti-charm quarks, which is otherwise not accessible, and is sensitive to soft heavy-flavour production. We report results on correlated $\rm e^{+}e^{-}$ pairs in pp collisions recorded by the ALICE detector at different collision energies. The production of heavy quarks is discussed by comparing the yield of dielectrons from heavy-flavour hadron decays as a function of invariant mass, pair transverse momentum and distance of closest approach to the primary vertex with different Monte Carlo event generators. The heavy-flavour production cross sections are also presented. Results from high-multiplicity pp collisions at $\sqrt{s} = 13$ TeV and the status of the p-Pb analysis at $\sqrt{s_{\rm NN}} = 5.02$ TeV are reported as well., Comment: Contribution to EPS-HEP 2019, submitted Proceedings of Science

The tau neutrino is one of the least studied particle in the Standard Model. Current tau neutrino-nucleon cross section measurement suffer large $\sim 30\%$ statistical and $\sim 50\%$ systematic uncertainties. In near future statistical uncertainty will be reduced to a few \% by the SHiP experiment, or by the experiments such as SHiP. DsTau (NA65) experiment at CERN aims to reduce the systematic uncertainty on tau neutrino-nucleon cross section through investigating a precise measurement on tau neutrino production, $Ds\rightarrow\tau+\nu_{\tau}$ differential production cross section with tungsten target. The uncertainty of the tau neutrino flux will be reduced to 10 \% from 50\%. Collaboration will collect $2.3\times10^{8}$ proton interactions with tungsten target and study about $10^5$ charm associated interactions. A pilot run was performed in 2018 Aug and collecting about a tenth of final statistics to perform full analysis chain. Here the analysis stream and the analysis status of 2018 Aug pilot run will be described.

We present our recent results on the extraction of the strong coupling, $\alpha_s$, from a new compilation of the hadronic $R$-ratio obtained from the available data for $e^+e^- \to {\rm hadrons}$. The determination uses all data up to $s=4$~GeV$^2$, where $s$ is the square of the center-of-mass energy. We obtain competitive values with only a small contamination from non-perturbative effects and with smaller theoretical uncertainties than the extractions from hadronic $\tau$ decays.

We investigate the possibility to constrain the intrinsic charm probability in proton $w_{c}$ using first ATLAS data on the associated production of prompt photons and charm-quark jets in $pp$ collisions at $\sqrt{s} = 8$ TeV. The upper limit on the intrinsic charm probability in proton $w_{ul} < 1.93$\% is obtained at the 68\% confidence level. This constraint is primarily determined by the theoretical scale and systematical experimental uncertainties.

I briefly review the various aspects of the fruitful interplay between flavor and high-$p_T$ physics, especially in our ongoing quest to uncover physics beyond the standard model. After elucidating the power of indirect flavor bounds compared to the direct reach of particle colliders, the possibility of flavor safe new physics is discussed. A brief introduction on the flavor probes of the standard model Higgs sector is followed by a detailed account of the numerous intertwined ways in which the persistent experimental anomalies in charged and neutral current mediated B decays interface with direct searches for new degrees of freedom at the LHC. In particular, the counterintuitive notion that SM gauge invariance together with flavor constraints from kaon and charm sectors implies new physics well within the kinematical reach of the LHC and orders of magnitude below the naive effective theory considerations is explained. Explicit illustrative model examples are provided throughout.

One of the important questions for the Belle II experiment is the CP violation in the charm sector. In the Standard Model, charm CP violation is expected to be very small beyond the sensitivity of Belle II. Therefore, its discovery can be a clear signal for new physics. In this talk, we present the efforts by Belle II in the studies of charm CP violation, trying to reduce the systematic uncertainties and to increase effective sample size. The main features of Belle II along with its initial performances will be discussed. Then studies of time-integrated and time-dependent charm CP violations are discussed with expectations for Belle II luminosity target.

We report on our calculation of the $B \to D^{(*)}\ell\nu$ form factors in 2+1 flavor lattice QCD. The Moebius domain-wall action is employed for light, strange, charm and bottom quarks. At lattice cutoffs $a^{-1} \sim 2.4$, 3.6 and 4.5 GeV, we simulate bottom quark masses up to 0.7 $a^{-1}$ to control discretization errors. The pion mass is as low as 230 MeV. We extrapolate the form factors to the continuum limit and physical quark masses, and make a comparison with recent phenomenological analyses.

We analyze the inclusive semileptonic $B \to X_c \ell\nu$ structure functions in 2+1-flavor lattice QCD. The M\"obius domain-wall fermion action is used for light, strange, charm and bottom quarks. The structure function receives contributions from various exclusive modes, including the dominant S-wave states $D^{(*)}_s$ as well as the P-wave states $D_s^{**}$. We can identify them in the lattice data, from which we put some constraints on the $B_s \to D_s^{**}\ell\nu$ form factors.

BESIII at BEPCII collider is a tau-charm factory with huge samples of on threshold charm meson pairs, directly produced charmonia and many other unique data sets.The Flavor Changing Neutral Current decays(FCNC) are forbidden at tree level in the Standard Model (SM) and are thus rare. Any direct observation beyond SM expectations could be a good probe of physics beyond SM. BESIII could probe these FCNC decays from multiple channels. Here we review some of search results of FCNC decays from BESIII. We present the latest results of searches. More results are coming in the future.

A potential upgrade of the SuperKEKB e$^+$e$^-$ collider with a polarized electron beam will open a new program of precision electroweak physics at the centre-of-mass energy of the $\Upsilon$(4S) and is currently being considered. These measurements include $\sin^2\theta_W$ obtained via left-right asymmetry measurements of e$^+$e$^-$ transitions to pairs of electrons, muons, taus, charm and b-quarks. The precision obtainable at SuperKEKB will match that of the LEP/SLC world average but at the centre-of-mass energy of 10.58~GeV, thereby probing the neutral current couplings with unprecedented precision at a new energy scale sensitive to the running of the couplings. World average measurements of the individual neutral current vector coupling constants to b- and c-quarks and muons in particular will be substantially improved and the residual $3\sigma$ discrepancy between the SLC $A_{LR}$ and LEP $A_{FB}^b$ measurements will be addressed. This paper will include a discussion of the necessary upgrades to SuperKEKB. This program opens an exciting new window in searches for physics beyond the standard model

In the past few years, a large number of unexpected new states, named as "charmonium-like states" or "$XYZ$ states", have been found above the open charm threshold. These exotic states containing a charm anti-charm quark pair, but cannot be simply described as $c\bar{c}$ bound states. In this proceeding, we review recent results in $XYZ$ study in BESIII experiment, including following analyses: $X(3872)\to\omega J/\psi$, $X(3872)\to\pi^0 \chi_{c1}$, $Y(4220)\to\omega \chi_{c0}$, $e^+e^-\to\pi^+\pi^-\psi(3770) \to\pi^+\pi^-D\bar{D}$ and $Z_{c} (3900)\to\rho\eta_{c}$.

The BESIII experiment at the Beijing Electron Positron Collider (BEPCII) has accumulated the world’s largest samples of $e+e−$ collisions in the tau-charm region. Based on the threshold open charm data samples $ofD(s)andΛ+c$, we can study the hadronic charm decays under a uniquely clean background. Many important results have been achieved with much-improved precision or for the first time. In this paper, we will review some recent results on the hadronic charm decays.Finally, a summary will be given.

Since the first XYZ particle $X(3872)$ was observed in 2003, many exotic states have been found by spectroscopy studies in beauty and charm hadrons. In this paper, the latest XYZ results are reviewed, mainly including $X(3872), X(3915), Y(4260), Y(4360), Y(4660), Z_c(3900), Z_c(4020)$ and $Z(4430)$. The spin parties of X and Z particles have been studied, and the comparison between different final states in Y particles has been done, which are helpful to understand the nature of XYZ particles.

A brief overview is given on the experimental study of strongly-interacting matter at high energy density as produced in ultra-relativistic heavy-ion collisions, focusing on recent results from the Large Hadron Collider at CERN. Soft particle production is discussed in terms of collective effects, where similarities are observed between nucleus-nucleus collisions and pp and p-Pb collisions, and the multiplicity-dependence of strange hadron yields in all collision systems. Hard probes of the produced Quark-Gluon Plasma (QGP) include jets and hadrons at high transverse momentum, where new measurements in Pb-Pb collisions and, in particular, the analysis of Xe-Xe collisions can provide further details on radiative parton energy loss in the QGP. New results on the production of open heavy-flavor hadrons provide further insight into the transport of heavy charm and beauty quarks in the dense medium and their interactions with it. Finally, measurements on the production of quarkonia give evidence for deconfinement in Pb-Pb collisions at the LHC and could help to determine the initial temperature of the produced QGP.

Heavy quarks, charm and beauty, are expected to be effective probes for the hot and dense medium (QGP) produced in high-energy heavy-ion collisions. They are produced in the early stage of the collision, almost exclusively in hard partonic scattering, and therefore they experience the full evolution of the QGP allowing to study the in-medium partonic energy-loss. In particular, the medium-induced parton energy loss is expected to depend on the parton mass and colour charge. This results in a reduction of beauty-quark energy loss compared to charm-quark energy loss. Therefore the separate measurement of the beauty-quark production from charm-quark production allows us to test various parton energy loss models. In addition, the measurement in pp collisions provides a crucial testing ground for perturbative QCD calculations and provides a mandatory baseline for corresponding studies in Pb-Pb collisions. In this paper, the measurements of beauty-hadron decay electrons in Pb-Pb collisions at $\sqrt{s_{NN}}$=5.02 TeV comparing with one at $\sqrt{s_{NN}}$=2.76 TeV is reviewed, and the status of the same study in pp collisions at $\sqrt{s}$=13 TeV is shown.

LHCb continues to expand its world-leading sample of charmed hadrons collected during LHC's Run 1 and Run 2. With this data set, LHCb is discovering many previously unobserved charmed states and making the most precise determinations of the properties of these states. This paper presents the recent LHCb results in charm spectroscopy, including the observation of five new excited $\Omega_c^0$ states, the study of excited $\Lambda_c^+$ states using the $\Lambda_b^0 \to D^0 p\pi^-$ decay, and the observation of the doubly charmed baryon $\Xi_{cc}^{++}$ in its decays to $\Lambda_c^+ K^-\pi^+\pi^+$ and $\Xi_c^+\pi^+$.

The ALICE (A Large Ion Collider Experiment) detector at the LHC (Large Hadron Collider) is dedicated to the study of the properties of the hot and dense QCD matter (Quark–Gluon Plasma) produced in the nucleus-nucleus collisions at high energy. Heavy quarks (charm and beauty), having large masses, are produced in the hard-parton scattering in the early stages of the collision. Therefore, they experience the whole evolution of the hot and dense medium, representing an important tool for its characterization. The study of angular correlations between D mesons and charged particles in Pb–Pb collisions gives insight about the energy loss of charm quarks and the medium-induced modification of its fragmentation into jets. Moreover, pp collisions help to understand the production mechanisms, fragmentation and hadronization of charm quarks and acts as a reference for p–Pb and Pb–Pb measurements. In this article, the measurement of azimuthal correlations between D0 meson and charged particles in pp collisions at TeV is presented. The collisional energy dependence of the correlations is extracted from the comparison with the results at TeV. The data are also compared with simulations performed with different event generators.

The $B_c$ meson is formed by two heavy quarks of different flavor, which makes it an interesting laboratory for test of effective theories of the strong interaction with a unique setting for production, decay and spectroscopy studies. This paper presents recent results on the $B_c$ meson from LHCb, including the $B_c^+$ mass, lifetime and production measurements, search for excited $B_c^+$ states, observation of the $B_c^+\to D^0 K^+$ decay, and search for $B_c^+$ decays to two charm mesons.