Search for new physics with charm rare decays at BESIII. The BESIII experiment has collected 2.6 billion $ψ(3686)$ events, 10 billion $J/ψ$ events, $20 fb^{-1}$ D meson pairs at 3.773 GeV, and $7.33 fb^{-1}~D_{s}D_{s}^{*}$ events from 4.128 to 4.226 GeV. The huge data samples allow us to search for rare processes in charm hadron decays. In this paper, we report the FCNC decay in $J/ψ\to D^0μ^+μ^-$, $J/ψ\to D^0γ$ and $D_{s}^{+}\to h(h')e^+e^-$. The search for $J/ψ$ weak decays containing a D meson, $J/ψ\to D_{s}^{-}π^{+}$, and $J/ψ\to D_{s}^{-}ρ^{+}$ will also be presented.
We present recent BESIII results about the study of mesons which contain at least one charm quark. We determined the D(s)+ decay constants, the form factors of D semi-leptonic decays, the CKM matrix elements |Vcs(d)|.
In recent years, lots of studies of charmonium decays have been performed at BESIII based on large data samples of $J/ψ$, $ψ(3686)$ and $ψ(3770)$. Recent results in searches for radiative transitions of $ψ(3770)$ and rare phenomena in charmonium decays, and studies of light hadrons structures and properties will be presented.
We report the latest outcomes for the Charmonium system investigation on 226x10^6 J/Psi and 106x10^6 Psi' events collected with the BESIII detector at the BEPCII e+e- collider.
In this talk, we will present the results on the charmonium spin singlet states below the open charm threshold, including h_c, η_c, and η_c(2S). The masses, widthes, and production rates of these states will be reported. The results are based on a data sample of 106 million ψ' events collected with the BESIII experiments at the BEPCII collider.
In 2009, the BESIII experiment has collected about 225M $\jpsi$ and 106M $\psip$ samples, both of which are the world largest on-peak charmonium production. Based on these dataset, BESIII has made great effort on the study of the charmonium decays, some important of which have been reviewed in this proceeding. In addition, a searching for new physics through the $CP/P$ violation process is reported.
The BESIII experiment at the Beijing Electron Positron Collider (BEPCII) has accumulated the world's largest samples of direct $e^+e^-$ collisions in the $τ$-charm region. From the collected samples, which include $e^+e^-$ annihilations at $J/ψ$, $ψ'$, $ψ$(3770) peaks and in the region from 3.8$\,$GeV to 4.6$\,$GeV, BESIII has produced many new physics results in the spectroscopy, transitions, and decays of charmonium(-like) states. This talk will cover the latest results over a wide range of topics from radiative and hadronic transitions among charmonium states, as well as the productions and…
Despite the successes of the standard model, the non-perturbative dynamics of the strong interaction are not fully understood yet. Charmonium spectroscopy serves as an ideal tool to shed light on the dynamics of the strong interaction such as quark confinement and the generation of hadron masses. The BESIII collaboration studies extensively the strong interaction and various aspects that could shed light on physics beyond the standard model via copious e$^+$e$^-$ collisions at the BESIII/BEPCII facility in Beijing, China, in the charmonium mass regime. I present a few of the recent results wit…
Hadron spectroscopy is one of the most important physics goals of BESIII. BESIII brings great opportunities to study the XYZ states of charmonium by directly producing the Y states up to 4.6 GeV. High statistics of charmonium decays collected at BESIII provide an excellent place for hunting gluonic excitations and studying the excited baryons. Recent results of light hadron spectroscopy and charmonium spectroscopy from BESIII will be reported.
I report BESIII preliminary results on: 1 Measurement of sigma(e+e- ->DDbar at Ecm = 3.773 GeV 2 Study of the DDbar production line shape near Ecm = 3.773 GeV 3 The first observation of singly Cabibbo-suppressed decay, D -> omega pi 4 Measurement of BF(Ds+ -> eta' X) and BF(Ds+ -> eta' rho+) .
I present here a selection of preliminary results on charmed hadron decays from BESIII collaboration, including the study of $D^{+}\to K^{-}π^{+}e^{+}ν_{e}$, the measurement of the form factors in $D^{+}\to ωe^{+}ν_{e}$ and the search for $D^{+}\to ϕe^{+}ν_{e}$, the study of decay dynamics and \emph{CP} asymmetry in $D^{+}\to K^{0}_{L} e^{+}ν_{e}$, and the measurements of the absolute branching fractions of twelve Cabbibo-favored hadronic $\lambdacp$ decay modes and $Λ^+_c\rightarrow Λe^+ν_e$. The results are based on the data samples collected with the BESIII detector at the $ψ(3770)$ peak an…
Based on the data samples collected at the energies of $J/ψ$, $ψ(3686)$, $ψ(3770)$ and $ψ(4040)$ resonances with the BESIII detector at the BEPCII storage ring, we present charmonium decays in two aspects. One is the search for baryonic decays of $ψ(3770)$ and $ψ(4040)$, including $Λ\barΛπ^+π^-$, $Λ\barΛπ^0$, $Λ\barΛη$, $Σ^+ \barΣ^-$, $Σ^0 \barΣ^0$, $Ξ^-\barΞ^+$ and $Ξ^0\barΞ^0$. None are observed, and upper limits are set at the 90% confidence level. The other is the light hadron spectroscopy from charmonium radiative decays, including the spin-parity analysis of the $p\bar p$ mass-threshold …
The study of mesons and baryons which contain at least one charm quark is referred to as open charm physics. It offers the possibility to study up-type quark transitions. Since the $c$ quark can not be treated in any mass limit, theoretical predictions are difficult and experimental input is crucial. BESIII collected large data samples of $e^{+}e^{-}$ collisions at several charm thresholds. The at-threshold decay topology offers special opportunities to study open charm decays. We present a selection of recent BESIII results. Branching fractions and the $D_{s}^{+}$ decay constant are measured …
The next generation tau-charm factory, the third Beijing Electron Spectrometer (BESIII) at the new Beijing Electron Positron Collider (BEPCII), has begun data collection. I discuss the flavor physics reach of the BESIII charm program and conclude with a discussion on future proposed tau-charm facilities.
Results based on 106 M $ψ'$ events and about 226 M $J/ψ$ events acquired with the BESIII detector at BEPCII are reported, including a confirmation of the BESII $p\bar{p}$ threshold enhancement in $J/ψ\to γp\bar{p}$, branching ratios for $χ_{cJ} \to π^0 π^0$ and $ηη$, and first measurements of the branching ratios for $ψ' \to π^0 h_c$ and $h_c \to γη_c$, as well as measurements of the mass and width of the $h_c$. Also reported are first observations of the two photon process $ψ' \to γγJ/ψ$ and $f_0(980) - a_0(980)$ mixing.
Charm physics has been studied with many dedicated accelerators and experiments. In these proceedings, we review the status and the selected results of the current operating BEPCII/BESIII experiment. We also discuss the BESIII data taking plan for the future.
Several states that couple to one light-meson and a heavy-charmonium are recently reported, including the $Z_c(3900)$ and $Z_c(4020)$. These states cannot be interpreted within the constituent quark-model of mesons, and are good candidates for a new form of quark matter, four-quark matter. A review of recent results on new charmonium-like states studied at BESIII is presented.
We present a selection of recent results from the BESIII collaboration, including both charmonium and $D$ meson physics. We first discuss the observation of a charged, charmonium-like state, the $Z_c(3900)$. Conventional charmonium topics include a search for lepton flavor violation, studies of $χ_{cJ} \to γγ$ decays, and mass and width determinations for the $h_c$, $η_c(1S)$, and $η_c(2S)$. We finish with results on the decay constant $f_D$ from $D^+ \to μ^+ ν$ and on form-factors in $D^0 \to K^- e^+ ν, π^- e^+ ν$.
About 2.9 fb$^{-1}$ data set had been collected with the BESIII detector at the BEPCII collider. Taking advantages of data near open-charm threshold, we present preliminary results on leptonic and semileptonic charm-meson decays, as well as result on the FCNC process $D^0 \rightarrow γγ$ from BESIII experiment. High precision charm data will enable us to validate Lattice QCD calculations at the few percent level. These can then be used to make precise measurements of CKM elements, $V_{cd}$ and $V_{cs}$, which are useful to improve the accuracy of test of the CKM unitary.
We present the most recent results from the BESIII experiment. This review covers the studies of charmonium decays, light hadron spectroscopy and charm physics. Especially, the prospects for weak decays of charm mesons are addressed at the BESIII.
The BESIII experiment at BEPCII at IHEP in Beijing/China has collected the world largest data sets in the $τ$-charm region and it is well suited to cover a rich hadron physics programme, including charmonium and open-charm spectroscopy, $R$-scan or electromagnetic form factor measurements, and many more. In particular, the unique data sets between 3.8 and 4.6\,GeV allow for discoveries and precision measurements of the interesting charmonium-like (exotic) `XYZ' states. The recently published precision cross-section measurement for $Y$ states is discussed as well as the first observation of the…
The BESIII Experiment at the Beijing Electron Positron Collider (BEPCII) collected large data samples for electron-positron collisions with center-of-mass above 4 GeV. The analysis of these samples has resulted in a number of surprising discoveries, such as the discoveries of the electrically charged $\mathrm{Z_c}$ structures, which, if resonant, cannot be accommodated in the traditional charm quark and anti-charm quark picture of charmonium. In this talk, we will review the current status of the analyses of the exotic states, as well as a number of other interesting features in the new BESIII…
With the ability to run above 4~GeV, the BESIII experiment located in the Beijing Electron Positron Collider (BEPCII), has becoming a pioneer in searching and studying charmoniumlike states ($XYZ$ particles). In 2013, BESIII Collaboration discovered a charged charmoniumlike state $Z_c(3900)$, which is confirmed immediately experimentally, and provides the best candidate for a four quark state by now. Continuous studies by BESIII Collaboration show new decay behavior of $Z_c(3900)$, and there are possible partner particle $Z_c(4020)/Z_c(4025)$ existing. By scanning above 4~GeV, BESIII also reve…
Amplitude analysis for charmed meson decays at BESIII
Zhengzhou University（郑州大学）；Nankai University（南开大学）；Institute of High Energy Physics（高能物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）；Jilin University（吉林大学）；Central South University（中南大学）
Despite the successes of the standard model, the non-perturbative dynamics of the strong interaction are not fully understood yet. Charmonium spectroscopy serves as an ideal tool to shed light on the dynamics of the strong interaction such as quark confinement and the generation of hadron masses. The BESIII collaboration studies extensively the strong interaction and various aspects that could shed light on physics beyond the standard model via copious e$^+$e$^-$ collisions at the BESIII/BEPCII facility in Beijing, China, in the charmonium mass regime. We present a few of the recent results wi…
In this document we present the latest result on rare/forbidden decays for D mesons at the BESIII experiment. Based on 2.92/fb data taken at the center-of-mass energy 3.773 GeV with the BESIII detector, the flavor-changing neutral current process of neutral D decays into two gammas is searched using a double tag technique, while the decays of charged D decays into a charged kaon/pion plus two electrons/positrons are studied based on a single tag method. The resulting upper limits are still above the Standard Model predictions.
The recent results on Charmonium and Charmonium-like states at BESIII are reviewed, including the observation of $\rm Z_{cs}(3985)$ state, the study of the new decay modes of $ψ_2(3823)$ state, observation of resonance structure in $\rm e^+e^- \to π^+π^-ψ_2(3823)$ process, the study of the $\rm e^+e^- \to K^+K^-J/ψ$ process, cross section measurement of $\rm e^+e^- \to ωπ^0$ and $ωη$ process, branching fraction measurement of $ψ(3686)\to\barΣ^0Λ+ c.c.$ process. Decay channels for $χ_{cJ} \to Λ\barΛ$, $χ_{cJ} \to Λ\barΛη$, $ψ(3686) \to Λ\barΛω$ and $η_c(2S)\to3(π^+π^-)$ are also discussed. The …
BESIII is a currently running tau-charm factory with the largest samples of on threshold charm meson pairs, directly produced charmonia and some other unique datasets at BEPCII collider. Machine learning techniques have been employed to improve the performance of BESIII software. The studies for reweighing MC, particle identification and cluster reconstruction for the CGEM (Cylindrical Gas Electron Multiplier) inner tracker are presented.
The Beijing Spectrometer (BESIII) collaboration uses $e^+e^-$ collisions in the tau-charm energy region to study a broad spectrum of topics. These include studies of light mesons and light baryons, studies of charmonium, including exotic mesons and baryons containing charmonium, studies of charmed mesons and baryons, studies of QCD and tau physics, as well as searches for new physics. The following is a Snowmass white paper that outlines the BESIII accomplishments and potential in each of these areas.
The Flavor Changing Neutral Current decays(FCNC) is forbidden at tree level in the Standard Model (SM) and could only contribute through loops. Any direct observation beyond SM expectations could be a good probe of physics beyond SM. BESIII is a currently running tau-charm factory with the largest samples of on threshold charm meson pairs, directly produced charmonia and some other unique datasets at BEPCII collider. It has great potential to probe these FCNC decays from multiple channels. Here we review some of latest search results of FCNC decays from BESIII. We present the latest results of…
Recently, LHCb experiment announced a 3.5$σ$ evidence for direct CP violation in $D^0$ decay by looking at the difference between $A_{CP}(D^0\rightarrow K^+K^-)$ and $A_{CP}(D^0\rightarrow π^+π^-)$. This is the first evidence of CP violation in charm system, which may indicate new physics beyond the Standard Model. Motivated by this measurement, we review rare processes in charmonium decay, especially, the weak decay, $C$ or $P$ violated decay and lepton flavor violated decays. In case the new physics appears in charm sector, these rare decays of charmonium states will provide opportunity to s…
A comprehensive review of weak decays of charmed hadrons ($D^{0/+}$, $D^+_s$ and $Λ^+_c$) based on analyses of the threshold data from $e^+e^-$ annihilation in the BESIII experiment is presented. Current experimental challenges and successes in understanding decays of the charmed hadrons are discussed. Precise calibrations of QCD and tests of the Standard Model are provided by measurements of purely leptonic and semi-leptonic decays of charmed hadrons, and lepton universality is probed in purely leptonic decays of charmed mesons to three generations of leptons. Quantum correlations in threshol…
BESIII had collected large data samples on $J/ψ$ and $ψ^\prime$ peaks during the first run in 2009. From 2010 to 2011, about 2.9 fb$^{-1}$ integrated luminosity were obtained on the peak of $ψ(3770)$ for open charm physics. We review recent results on charmonium decays and hadron spectroscopy. The prospects on open charm physics are also discussed.
A selection of results from electron-positron collisions at BESIII are reviewed. The results presented here illustrate the wide range of physics topics that can be studied using the Beijing Electron Positron Collider~(BEPC). At low collision energies, the cross section for $e^+e^-\to π^+π^-$ provides much-needed input into theoretical calculations of the anomalous magnetic moment of the muon, and the reaction $e^+e^-\to p\bar{p}$ provides access to the electromagnetic form factors of the proton. In the charmonium region, a large sample of $ψ^\prime$ decays can be used to measure new decay mode…
Based on a data sample of $(448.1\pm2.9)\times10^6~ψ(3686)$ decays collected with the BESIII experiment, a search for the flavor changing neutral current transition $ψ(3686)\rightarrow Λ_c^+ \overline{p} e^+ e^- + c.c.$ is performed for the first time. No signal candidates are observed and the upper limit on the branching fraction of $ψ(3686)\rightarrow Λ_c^+ \overline{p} e^+ e^-$ is determined to be $1.7\times10^{-6}$ at the 90\% confidence level. The result is consistent with expectations from the Standard Model, and no evidence for new physics is found.
Charm hadronic decays are an important tool for understanding the the hadron spectroscopy and dynamics of the strong interaction in the low energy regime. BESIII experiment has collected a huge amount of data at various energy points around $D\bar{D}$ and $D_sD_s^*$ threshold. This report summarizes recent amplitude analyses and branching fraction measurements results of BESIII related to $D_{(s)}$ decays.
Light hadron spectroscopy plays an important role in understanding the decay dynamics of unconventional hadronic states, such as strangeonium and glueballs. BESIII provides an ideal avenue to search for these exotic states thanks to a huge amount of data recorded at various energy points in the tau-charm mass region including J/psi resonance. This report summarizes recent results of the BESIII experiment related to the glueballs and strangeonium-like states.
Based on $ψ(3686)$ decays of 106 million, the 1.31 billion J/psi events and a data sample of $ψ(3770)$ with $2.9~fb^{-1}$ integrated luminosity, many analyses are performed. Exclusively baryonic decays of the $ψ(3770)$, the radiative transition $ψ(3770)\toγη_c(2S)$, the $ψ(3770)$ transition to $χ_{cJ}$, isospin violation decay $χ_{c0,2}\toπ^0η_c$, the $C-$parity violation decays $J/ψ\toγγ,γϕ$ are searched for, but no significant signals are observed, and upper limits are set for these decays. The decays of $ψ(3770)\toγχ_{c1}$ and $J/ψ\toπ^0ϕ$ signals are observed. These measurements provide mo…
We report some recent results on charmonium spectroscopy and hadron spectroscopy from BESIII experiment, including the measurements of the masses and widths of $h_c$, $η_c$, $η_c(2S)$ and some new resonances around 2 GeV. The results are based on a data sample of 106 million $ψ^\prime$ events and 226 million J/$ψ$ events collected with the BESIII detector at the BEPCII collider.
Experimental Advances on Light Baryon Spectroscopy at BESIII Experiment
Lanzhou University（兰州大学）；Institute of High Energy Physics（高能物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）；Institute of Physics, Henan Academy of Sciences（河南省科学院物理研究所）
Many extensions of the Standard Model introduce a new type of weak-interacting degrees of freedom. These models are motivated by the results of recent experimental anomalies. Typical models, such as Next-to-Minimal Supersymmetric Standard Model and Light Hidden Dark-sector Model, introduce the possibilities of low-mass Higgs and dark bosons. The masses of such particles are expected to be few GeV and thus making them accessible at BESIII experiment, an $e^+e^-$ collider experiment running at tau-charm region. This report summarizes the recent results of low-mass Higgs and dark bosons searches …
BESIII experiment has collected about 20 fb$^{-1}$ luminosity data between $\sqrt{s}=3.8$ and 4.7 GeV via $e^{+}e^{-}$ collision. In this talk, we present the recent $XYZ$ results at BESIII, including mass and width measurements of $Y(4220)$, search for $Y$ states with rare decay modes, isospin parity determination of $Z_{c}^{0}(3900)$ as well as the mass and width determination, and search for new decay modes of $X(3872)$.
