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Measurement of the $\Lambda_b$ polarization and angular parameters in $\Lambda_b\to J/\psi\, \Lambda$ decays from pp collisions at $\sqrt{s}=$ 7 and 8 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D97 (2018) 072010, 2018.
Inspire Record 1654926 DOI 10.17182/hepdata.83664

An analysis of the bottom baryon decay Λb→J/ψ(→μ+μ-)Λ(→pπ-) is performed to measure the Λb polarization and three angular parameters in data from pp collisions at s=7 and 8 TeV, collected by the CMS experiment at the Large Hadron Collider. The Λb polarization is measured to be 0.00±0.06(stat)±0.06(syst) and the parity-violating asymmetry parameter is determined to be 0.14±0.14(stat)±0.10(syst). The measurements are compared to various theoretical predictions, including those from perturbative quantum chromodynamics.

3 data tables

The measured values of the angular parameters and the $\Lambda_b$ polarization.

The values of the helicity amplitudes in the decay.

Correlation matrix for the fitted parameters.


Study of $D^{+} \to K^{-} \pi^+ e^+ \nu_e$

The BESIII collaboration Ablikim, Medina ; Achasov, Mikhail N ; Ai, Xiaocong ; et al.
Phys.Rev. D94 (2016) 032001, 2016.
Inspire Record 1411645 DOI 10.17182/hepdata.77048

We present an analysis of the decay D+→K-π+e+νe based on data collected by the BESIII experiment at the ψ(3770) resonance. Using a nearly background-free sample of 18262 events, we measure the branching fraction B(D+→K-π+e+νe)=(3.77±0.03±0.08)%. For 0.8<mKπ<1.0  GeV/c2, the partial branching fraction is B(D+→K-π+e+νe)[0.8,1.0]=(3.39±0.03±0.08)%. A partial wave analysis shows that the dominant K¯*(892)0 component is accompanied by an S-wave contribution accounting for (6.05±0.22±0.18)% of the total rate and that other components are negligible. The parameters of the K¯*(892)0 resonance and of the form factors based on the spectroscopic pole dominance predictions are also measured. We also present a measurement of the K¯*(892)0 helicity basis form factors in a model-independent way.

2 data tables

The $S$-wave phase $\delta_{S}$ measured in the 12 $m_{K\pi}$ bins with statistical and systematic uncertainties. The systematic uncertainties include: (I) background fraction, (II) background shape, (III) the $\bar K_{0}^{*}(1430)^{0}$ mass and width, (IV) additional resonances, (V) tracking efficiency correction, (VI) PID efficiency correction.

Average form-factor products in the $K^{*}$-dominated region.


Measurement of the I=1/2 $K \pi$ $\mathcal{S}$-wave amplitude from Dalitz plot analyses of $\eta_c \to K \bar K \pi$ in two-photon interactions

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.
Phys.Rev. D93 (2016) 012005, 2016.
Inspire Record 1403544 DOI 10.17182/hepdata.76968

We study the processes $\gamma \gamma \to K^0_S K^{\pm}\pi^{\mp}$ and $\gamma \gamma \to K^+ K^- \pi^0$ using a data sample of 519~$fb^{-1}$ 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 $\Upsilon(nS)$ ($n = 2,3,4$) resonances. We observe $\eta_c$ decays to both final states and perform Dalitz plot analyses using a model-independent partial wave analysis technique. This allows a model-independent measurement of the mass-dependence of the $I=1/2$ $K \pi$ $\mathcal{S}$-wave amplitude and phase. A comparison between the present measurement and those from previous experiments indicates similar behaviour for the phase up to a mass of 1.5 $GeV/c^2$. In contrast, the amplitudes show very marked differences. The data require the presence of a new $a_0(1950)$ resonance with parameters $m=1931 \pm 14 \pm 22 \ MeV/c^2$ and $\Gamma=271 \pm 22 \pm 29 \ MeV$.

2 data tables

Measured amplitude and phase values for the $I=1/2$ $K \pi$ $\mathcal{S}$-wave as functions of mass obtained from the Model Independent Partial Wave Analysis (MIPWA) of $\eta_c \to K^0_{\scriptscriptstyle S} K^{\pm}\pi^{\mp}$. The amplitudes and phases in the mass interval 14 are fixed to constant values.

Measured amplitude and phase values for the $I=1/2$ $K \pi$ $\mathcal{S}$-wave as functions of mass obtained from the Model Independent Partial Wave Analysis (MIPWA) of $\eta_c \to K^+ K^- \pi^0$. The amplitudes and phases in the mass interval 14 are fixed to constant values.


First measurement of the differential branching fraction and $C\!P$ asymmetry of the $B^\pm\to\pi^\pm\mu^+\mu^-$ decay

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1510 (2015) 034, 2015.
Inspire Record 1391325 DOI 10.17182/hepdata.75486

The differential branching fraction with respect to the dimuon invariant mass squared, and the CP asymmetry of the B$^{±}$ → π$^{±}$ μ$^{+}$ μ$^{−}$ decay are measured for the first time. The CKM matrix elements |V$_{td}$ | and |V$_{ts}$ |, and the ratio |V$_{td}$ /V$_{ts}$ | are determined. The analysis is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb$^{−1}$, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The total branching fraction and CP asymmetry of B$^{±}$ → π$^{±}$ μ$^{+}$ μ$^{−}$ decays are measured to be $ \begin{array}{l}\mathrm{\mathcal{B}}\left({B}^{\pm}\to {\pi}^{\pm }{\mu}^{+}{\mu}^{-}\right)=\left(1.83\pm 0.24\pm 0.05\right)\times {10^{-}}^8\,\mathrm{and}\hfill \\ {}{\mathcal{A}}_{CP}\left({B}^{\pm}\to {\pi}^{\pm }{\mu}^{+}{\mu}^{-}\right)=-0.11\pm 0.12\pm 0.01,\hfill \end{array} $ where the first uncertainties are statistical and the second are systematic. These are the most precise measurements of these observables to date, and they are compatible with the predictions of the Standard Model.

1 data table

The results for the differential branching fraction for $B^+ \rightarrow \pi^+\mu^+\mu^-$ in bins of $q^2$.


Study of the production of $\Lambda_b^0$ and $\overline{B}^0$ hadrons in $pp$ collisions and first measurement of the $\Lambda_b^0\rightarrow J/\psi pK^-$ branching fraction

The LHCb collaboration Aaij, R. ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
Chin.Phys. C40 (2016) 011001, 2016.
Inspire Record 1391317 DOI 10.17182/hepdata.75485

The product of the differential production cross-section and the branching fraction of the decay is measured as a function of the beauty hadron transverse momentum, p(T), and rapidity, y. The kinematic region of the measurements is p(T) < 20 GeV/c and 2.0 < y < 4.5. The measurements use a data sample corresponding to an integrated luminosity of 3fb(−)(1) collected by the LHCb detector in pp collisions at centre-of-mass energies in 2011 and in 2012. Based on previous LHCb results of the fragmentation fraction ratio the branching fraction of the decay is measured to bewhere the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay B̅(0) → J/ψK̅*(892)(0), and the fourth is due to the knowledge of . The sum of the asymmetries in the production and decay between and is also measured as a function of p(T) and y. The previously published branching fraction of , relative to that of , is updated. The branching fractions of are determined.

6 data tables

Products of $\Lambda_b^0$ production cross-sections and the branching fraction $\mathcal{B}(\Lambda_b^0 \rightarrow J\psi pK^-)$ in bins of $p_\rm{T}$ and $y$ in the 2011 data sample.

Products of $\Lambda_b^0$ production cross-sections and the branching fraction $\mathcal{B}(\Lambda_b^0 \rightarrow J\psi pK^-)$ in bins of $p_\rm{T}$ and $y$ in the 2012 data sample.

Products of $\overline{B}^0$ production cross-sections and $\mathcal{B}(\overline{B}^0 \rightarrow J\psi \overline{K}^{*0})$ in bins of $p_\rm{T}$ and $y$ in the 2011 data sample.

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Measurement of angular asymmetries in the decays $B \to K^*ℓ^+ℓ^-$

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.
Phys.Rev. D93 (2016) 052015, 2016.
Inspire Record 1391152 DOI 10.17182/hepdata.75484

We study the lepton forward-backward asymmetry AFB and the longitudinal K* polarization FL, as well as an observable P2 derived from them, in the rare decays B→K*ℓ+ℓ-, where ℓ+ℓ- is either e+e- or μ+μ-, using the full sample of 471 million BB¯ events collected at the ϒ(4S) resonance with the BABAR, detector at the PEP-II e+e- collider. We separately fit and report results for the K*0(892)ℓ+ℓ- and K*+(892)ℓ+ℓ- final states, as well as their combination K*ℓ+ℓ-, in five disjoint dilepton mass-squared bins. An angular analysis of B+→K*+ℓ+ℓ- decays is presented here for the first time.

3 data tables

$F_L$ angular fit results.

$A_{FB}$ angular fit results.

$P_2$ results with total uncertainties.


Study of Dynamics of $D^0 \to K^- e^+ \nu_{e}$ and $D^0\to\pi^- e^+ \nu_{e}$ Decays

The BESIII collaboration Ablikim, M. ; Achasov, M.N. ; Ai, X.C. ; et al.
Phys.Rev. D92 (2015) 072012, 2015.
Inspire Record 1391138 DOI 10.17182/hepdata.74726

In an analysis of a 2.92~fb$^{-1}$ data sample taken at 3.773~GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be $\mathcal B(D^0 \to K^-e^+\nu_e)=(3.505\pm 0.014 \pm 0.033)\%$ and $\mathcal B(D^0 \to \pi^-e^+\nu_e)=(0.295\pm 0.004\pm 0.003)\%$. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element $f_{+}^K(0)|V_{cs}|=0.7172\pm0.0025\pm 0.0035$ and $f_{+}^{\pi}(0)|V_{cd}|=0.1435\pm0.0018\pm 0.0009$. Combining these products with the values of $|V_{cs(d)}|$ from the SM constraint fit, we extract the hadronic form factors $f^K_+(0) = 0.7368\pm0.0026\pm 0.0036$ and $f^\pi_+(0) = 0.6372\pm0.0080\pm 0.0044$, and their ratio $f_+^{\pi}(0)/f_+^{K}(0)=0.8649\pm 0.0112\pm 0.0073$. These form factors and their ratio are used to test unquenched Lattice QCD calculations of the form factors and a light cone sum rule (LCSR) calculation of their ratio. The measured value of $f_+^{K(\pi)}(0) |V_{cs(d)}|$ and the lattice QCD value for $f^{K(\pi)}_+(0)$ are used to extract values of the CKM matrix elements of $|V_{cs}|=0.9601 \pm 0.0033 \pm 0.0047 \pm 0.0239$ and $|V_{cd}|=0.2155 \pm 0.0027 \pm 0.0014 \pm 0.0094$, where the third errors are due to the uncertainties in lattice QCD calculations of the form factors. Using the LCSR value for $f_+^\pi(0)/f_+^K(0)$, we determine the ratio $|V_{cd}|/|V_{cs}|=0.238\pm 0.004\pm 0.002\pm 0.011$, where the third error is from the uncertainty in the LCSR normalization. In addition, we measure form factor parameters for three different theoretical models that describe the weak hadronic charged currents for these two semileptonic decays. All of these measurements are the most precise to date.

2 data tables

Summary of the range of each $q^2$ bin, the number of the observed events $N_{\rm observed}$, the number of produced events $N_{\rm produced}$, and the partial decay rate $\Delta\Gamma$ in each $q^2$ bin for $D^0\to K^-e^+\nu_e$ decays.

Summary of the range of each $q^2$ bin, the number of the observed events $N_{\rm observed}$, the number of produced events $N_{\rm produced}$, and the partial decay rate $\Delta\Gamma$ in each $q^2$ bin for $D^0\to \pi^-e^+\nu_e$ decays.


Search for a low-mass pseudoscalar Higgs boson produced in association with a $b\bar{b}$ pair in pp collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B758 (2016) 296-320, 2016.
Inspire Record 1403990 DOI 10.17182/hepdata.73991

A search is reported for a light pseudoscalar Higgs boson decaying to a pair of τ leptons, produced in association with a bb‾ pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 fb −1 . Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the product of cross section and branching fraction to τ pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with SM-like Higgs boson negative couplings to down-type fermions, produced in association with bb‾ pairs, in Type II, two-Higgs-doublet models.

1 data table

Expected and observed 95 % CL combined upper limits in pb on pseudoscalar Higgs bosons produced in association with bb pairs, along with their 1 and 2 standard deviation uncertainties.


Angular analysis and differential branching fraction of the decay $B^0_s\to\phi\mu^+\mu^-$

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1509 (2015) 179, 2015.
Inspire Record 1380188 DOI 10.17182/hepdata.73774

An angular analysis and a measurement of the differential branching fraction of the decay B$^{s}$  → ϕμ$^{+}$ μ$^{−}$ are presented, using data corresponding to an integrated luminosity of 3.0 fb$^{−1}$ of pp collisions recorded by the LHCb experiment at $ \sqrt{s}=7 $ and 8 TeV. Measurements are reported as a function of q$^{2}$, the square of the dimuon invariant mass and results of the angular analysis are found to be consistent with the Standard Model. In the range 1 < q$^{2}$ < 6 GeV$^{2}$ /c$^{4}$, where precise theoretical calculations are available, the differential branching fraction is found to be more than 3σ below the Standard Model predictions.

3 data tables

The signal yields for $B_s^0 \to \phi\mu^+\mu^-$ decays, as well as the differential branching fraction relative to the normalisation mode and the absolute differential branching fraction, in bins of $q^2$. The given uncertainties are (from left to right) statistical, systematic, and the uncertainty on the branching fraction of the normalisation mode.

(Top) $CP$-averaged angular observables $F_{\rm L}$ and $S_{3,4,7}$ obtained from the unbinned maximum likelihood fit.

(Bottom) $CP$ asymmetries $A_{5,6,8,9}$ obtained from the unbinned maximum likelihood fit.


Observation of the Dalitz Decay $\eta' \to \gamma e^+e^-$

The BESIII collaboration Ablikim, M. ; Achasov, M.N. ; Ai, X.C. ; et al.
Phys.Rev. D92 (2015) 012001, 2015.
Inspire Record 1364494 DOI 10.17182/hepdata.73672

We report the first observation of the Dalitz decay $\eta' \to \gamma e^+e^-$, based on a data sample of 1.31 billion $J/\psi$ events collected with the BESIII detector. The $\eta'$ mesons are produced via the $J/\psi \to \gamma \eta'$ decay process. The ratio $\Gamma(\eta' \to \gamma e^+ e^-)/\Gamma(\eta'\to\gamma\gamma)$ is measured to be $(2.13\pm0.09(\text{stat.})\pm0.07(\text{sys.}))\times10^{-2}$. This corresponds to a branching fraction ${\cal B}(\eta' \to \gamma e^+e^-)= (4.69 \pm0.20(\text{stat.})\pm0.23(\text{sys.}))\times10^{-4}$. The transition form factor is extracted and different expressions are compared to the measured dependence on the $e^+e^-$ invariant mass. The results are consistent with the prediction of the Vector Meson Dominance model.

2 data tables

Fitted ($n^{\text{obs}}_i$) and efficiency-corrected ($n^{\text{corr}}_i$) signal yields for the eight $M(e^+e^-)$ bins, and ratios ($r_i$). The uncertainties are statistical only.

Values of $|F|^2$ in each $M(e^+e^-)$ bin.


Observation of $D^0$ Meson Nuclear Modifications in Au+Au Collisions at $\sqrt{s_{NN}}=200$  GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.Lett. 113 (2014) 142301, 2014.
Inspire Record 1292132 DOI 10.17182/hepdata.73474

We report the first measurement of charmed-hadron ($D^0$) production via the hadronic decay channel ($D^0\rightarrow K^- + \pi^+$) in Au+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200\,GeV with the STAR experiment. The charm production cross-section per nucleon-nucleon collision at mid-rapidity scales with the number of binary collisions, $N_{bin}$, from $p$+$p$ to central Au+Au collisions. The $D^0$ meson yields in central Au+Au collisions are strongly suppressed compared to those in $p$+$p$ scaled by $N_{bin}$, for transverse momenta $p_{T}>3$ GeV/$c$, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate $p_{T}$ is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

3 data tables

Centrality dependence of the $D^0$ $p_T$ differential invariant yield in Au+Au collisions.

$D^0\,R_{AA}$ for different centralities.

Integrated $D^0$ $R_{AA}$ as a function of $N_{part}$ in different $p_T$ regions.


Search for pair production of a new heavy quark that decays into a $W$ boson and a light quark in $pp$ collisions at $\sqrt{s} = 8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D92 (2015) 112007, 2015.
Inspire Record 1393281 DOI 10.17182/hepdata.71069

A search is presented for pair production of a new heavy quark (Q) that decays into a W boson and a light quark (q) in the final state where one W boson decays leptonically (to an electron or muon plus a neutrino) and the other W boson decays hadronically. The analysis is performed using an integrated luminosity of 20.3  fb-1 of pp collisions at s=8  TeV collected by the ATLAS detector at the LHC. No evidence of QQ¯ production is observed. New chiral quarks with masses below 690 GeV are excluded at 95% confidence level, assuming BR(Q→Wq)=1. Results are also interpreted in the context of vectorlike quark models, resulting in the limits on the mass of a vectorlike quark in the two-dimensional plane of BR(Q→Wq) versus BR(Q→Hq).

2 data tables

The expected and observed 95% CL upper limits on the cross section as a function of $m_Q$ when setting BR$(Q\to Wq) = 1$, which would be the case for a new chiral quark. Also shown are the $\pm 1\sigma$ and $\pm 2\sigma$ intervals on the distribution of expected results for the chiral model if no signal exists.

The upper and lower bounds on the range of heavy quark masses expected and observed to be excluded at 95% CL, as a function of the branching ratio of the heavy quark to $Wq$ versus $Hq$, with the branching ratio to $Zq$ fixed by the requirement BR$(Q\!\to\!Zq) = 1 - \text{BR}(Q\!\to\!Wq) - \text{BR}(Q\!\to\!Hq)$.


Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1410 (2014) 160, 2014.
Inspire Record 1310838 DOI 10.17182/hepdata.70761

A search for neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM) decaying to tau-lepton pairs in pp collisions is performed, using events recorded by the CMS experiment at the LHC. The dataset corresponds to an integrated luminosity of 24.6 fb$^{−1}$, with 4.9 fb$^{−1}$ at 7 TeV and 19.7 fb$^{−1}$ at 8 TeV. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes the case where the Higgs boson is produced in association with a b-quark jet. No excess is observed in the tau-lepton-pair invariant mass spectrum. Exclusion limits are presented in the MSSM parameter space for different benchmark scenarios, m$_{h}^{max}$ , m$_{h}^{mod +}$ , m$_{h}^{mod −}$ , light-stop, light-stau, τ-phobic, and low-m$_{H}$. Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given.

4 data tables

likelihood scan of the (gg$\rightarrow\phi\rightarrow\tau\tau$) - (gg$\rightarrow$bb$\phi\rightarrow\tau\tau$) - plane the with 40000 grid points at each hypothetical higgs mass, m$_\phi$, at $\sqrt{s}$ = 8 TeV testing the observation against a background hypothesis not including the Standard Model Higgs boson at 125 GeV.

likelihood scan of the (gg$\rightarrow\phi\rightarrow\tau\tau$) - (gg$\rightarrow$bb$\phi\rightarrow\tau\tau$) - plane the with 40000 grid points at each hypothetical higgs mass, m$_\phi$, at $\sqrt{s}$ = 8 TeV testing the $\textbf{asimov dataset of the sum of all backgrounds not including the Standard Model Higgs boson at 125 GeV against a background hypothesis not including the Standard Model Higgs boson at 125 GeV}.

likelihood scan of the (gg$\rightarrow\phi\rightarrow\tau\tau$) - (gg$\rightarrow$bb$\phi\rightarrow\tau\tau$) - plane the with 40000 grid points at each hypothetical higgs mass, m$_\phi$, at $\sqrt{s}$ = 8 TeV testing the observation against a background hypothesis including the Standard Model Higgs boson at 125 GeV.

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New measurement of the K+- --> pi+-mu+mu- decay

The NA48/2 collaboration Batley, J.R. ; Kalmus, G. ; Lazzeroni, C. ; et al.
Phys.Lett. B697 (2011) 107-115, 2011.
Inspire Record 878312 DOI 10.17182/hepdata.69636

A sample of 3120 $K^\pm\to\pi^\pm\mu^+\mu^-$ decay candidates with $(3.3\pm0.7)%$ background contamination has been collected by the NA48/2 experiment at the CERN SPS, allowing a detailed study of the decay properties. The branching ratio was measured to be ${\rm BR}=(9.62\pm0.25)\times 10^{-8}$. The form factor $W(z)$, where $z=(M_{\mu\mu}/M_K)^2$, was parameterized according to several models. In particular, the slope of the linear form factor $W(z)=W_0(1+\delta z)$ was measured to be $\delta=3.11\pm0.57$. Upper limits of $2.9\times 10^{-2}$ and $2.3\times 10^{-2}$ on possible charge asymmetry and forward-backward asymmetry were established at 90% CL. An upper limit ${\rm BR}(K^\pm\to\pi^\mp\mu^\pm\mu^\pm)<1.1\times 10^{-9}$ was established at 90% CL for the rate of the lepton number violating decay.

1 data table

The $d\Gamma_{\pi\mu\mu}/dz$ spectrum (background subtracted, corrected for trigger efficiency). Systematic errors, notably the external one due to the branching ratios of the normalization decay mode $K^\pm\to 3\pi^\pm$ according to PDG 2010, are not included.


Observation of parity-violating optical rotation in atomic thallium

Wolfenden, T.D. ; Baird, P.E.G. ; Sandars, P.G.H. ;
Europhys.Lett. 15 (1991) 731-736, 1991.
Inspire Record 331200 DOI 10.17182/hepdata.43748

Parity-violating optical rotation induced by the neutral weak-current interaction has been detected and measured for the first time in atomic thallium vapour. Accurate atomic calculations predicting the size of the rotation are available for this element; thallium also benefits from the Z3 enhancement of the effect. The magnetic-dipole transition 6p1/2-6p3/2 at 1.283 μm was excited using a single-mode semiconductor laser and the small optical rotation was measured using a sensitive polarimeter. The result, expressed in terms of the quantity R = Im E1p.v./M1, is - 12.5(19)10-8 and is consistent with recent calculations based on the standard model.

1 data table

Spin of the Tl nucleus is 1/2.


Search for charged Higgs bosons decaying via $H^{\pm} \rightarrow \tau^{\pm}\nu$ in fully hadronic final states using $pp$ collision data at $\sqrt{s} = 8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1503 (2015) 088, 2015.
Inspire Record 1335266 DOI 10.17182/hepdata.68153

The results of a search for charged Higgs bosons decaying to a τ lepton and a neutrino, H$^{±}$ → τ$^{±}$ ν, are presented. The analysis is based on 19.5 fb$^{−1}$ of proton-proton collision data at $ \sqrt{s} $ = 8 TeV collected by the ATLAS experiment at the Large Hadron Collider. Charged Higgs bosons are searched for in events consistent with top-quark pair production or in associated production with a top quark, depending on the considered H$^{±}$ mass. The final state is characterised by the presence of a hadronic τ decay, missing transverse momentum, b-tagged jets, a hadronically decaying W boson, and the absence of any isolated electrons or muons with high transverse momenta. The data are consistent with the expected background from Standard Model processes. A statistical analysis leads to 95% confidence-level upper limits on the product of branching ratios ℬ(t → bH$^{±}$) × ℬ(H$^{±}$ → τ$^{±}$ ν), between 0.23% and 1.3% for charged Higgs boson masses in the range 80-160GeV. It also leads to 95% confidence-level upper limits on the production cross section times branching ratio, σ(pp → tH$^{±}$ + X) × ℬ(H$^{±}$ → τ$^{±}$ ν), between 0.76 pb and 4.5 fb, for charged Higgs boson masses ranging from 180 GeV to 1000 GeV. In the context of different scenarios of the Minimal Supersymmetric Standard Model, these results exclude nearly all values of tan β above one for charged Higgs boson masses between 80 GeV and 160 GeV, and exclude a region of parameter space with high tan β for H$^{±}$ masses between 200 GeV and 250 GeV.

2 data tables

The measured B(t->H+)xB(H+->tau+ nu) limit.

The measured P P --> t H+ --> t tau+nu limit.


Measurement of the spectral functions of axial - vector hadronic tau decays and determination of alpha(S)(M**2(tau))

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Eur.Phys.J. C4 (1998) 409-431, 1998.
Inspire Record 467093 DOI 10.17182/hepdata.68902
7 data tables

Total vector spectral function. The error has been set to zero if it is smaller than the point size.

Invariant mass-squared distributions of the decay $\tau^- \to 2\pi^- \pi^+ \nu_\tau$. The error has been set to zero if it is smaller than the point size.

Invariant mass-squared distributions of the decay $\tau^- \to \pi^- 2\pi^0 \nu_\tau$. The error has been set to zero if it is smaller than the point size.

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Measurement of the spectral functions of vector current hadronic tau decays

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Z.Phys. C76 (1997) 15-33, 1997.
Inspire Record 440588 DOI 10.17182/hepdata.68475
6 data tables

Invariant mass-squared distribution of the $\tau^- \to h^- \pi^0 \nu_{\tau}$ decay. The error has been set to zero if it is smaller than the point size. A dash indicates a data point lying outside the plot range.

Invariant mass-squared distributions of the $h^- 3\pi^0 \nu_{\tau}$ decay channel. The error has been set to zero if it is smaller than the point size.

Invariant mass-squared distribution of the $2h^- h^+ \pi^0 \nu_{\tau}$ decay channel. The error has been set to zero if it is smaller than the point size.

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A Study of tau decays involving eta and omega mesons

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Z.Phys. C74 (1997) 263-273, 1997.
Inspire Record 421984 DOI 10.17182/hepdata.68382
6 data tables

$\pi^+\pi^-\pi^0$ mass distribution (two entries per event) in the $\pi^{\pm}\pi^+\pi^-\pi^0$ final state for the one-photon sample. The bin size has been chosen to display the detailed shape of the $\omega$ peak. The non-resonant contribution is represented by a simple polynomial. Non-$\tau$ background has been subtracted. The error has been set to zero if it is smaller than the point size.

$\pi^+\pi^-\pi^0$ mass distributions (two entries per event) in the $\pi^{\pm}\pi^+\pi^-\pi^0$ final state for the two-photon sample. The bin size has been chosen to display the detailed shape of the $\omega$ peak. The non-resonant contribution is represented by a simple polynomial. Non-$\tau$ background has been subtracted. The error has been set to zero if it is smaller than the point size.

Background-subtracted $\omega\pi$ mass spectrum for the data presented here, plotted as black dots. The error has been set to zero if it is smaller than the point size.

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Search for the dark photon in $\pi^0$ decays

The NA48/2 collaboration Batley, J.R. ; Kalmus, G. ; Lazzeroni, C. ; et al.
Phys.Lett. B746 (2015) 178-185, 2015.
Inspire Record 1357601 DOI 10.17182/hepdata.67658

A sample of $1.69\times 10^7$ fully reconstructed $\pi^0\to\gamma e^+e^-$ decay candidates collected by the NA48/2 experiment at CERN in 2003--2004 is analysed to search for the dark photon ($A'$) production in the $\pi^0\to\gamma A'$ decay followed by the prompt $A'\to e^+e^-$ decay. No signal is observed, and an exclusion region in the plane of the dark photon mass $m_{A'}$ and mixing parameter $\varepsilon^2$ is established. The obtained upper limits on $\varepsilon^2$ are more stringent than the previous limits in the mass range $9~{\rm MeV}/c^2<m_{A'}<70~{\rm MeV}/c^2$. The NA48/2 sensitivity to the dark photon production in the $K^\pm\to\pi^\pm A'$ decay is also evaluated.

1 data table

The obtained 90% CL upper limits (ULs) on the mixing parameter $\epsilon^2$ for each dark photon (DP) mass hypothesis tested.


K0 production in one prong tau decays

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Phys.Lett. B332 (1994) 219-227, 1994.
Inspire Record 373752 DOI 10.17182/hepdata.68011
1 data table

Invariant mass distribution for the $K^0\pi$ system data. The numbers have been read from the plot in the paper.


One prong tau decays into charged kaons

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Phys.Lett. B332 (1994) 209-218, 1994.
Inspire Record 373751 DOI 10.17182/hepdata.68012
1 data table

Invariant mass distribution of the $K\pi^0$ final state, as obtained from a $dE/dx$ fit in each mass bin. The numbers have been read from the plot in the paper, with the errors simply set to zero if they are smaller than the point size.


Study of the gamma gamma decays of the chi(c2) (1**3 P(2)) and chi(c0) (1**3 P(0)) charmonium resonances

Ambrogiani, M. ; Argiro, S. ; Bagnasco, S. ; et al.
Phys.Rev. D62 (2000) 052002, 2000.
Inspire Record 531059 DOI 10.17182/hepdata.3517
1 data table

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