Fri·Nov 5, 2021Friday·November 5, 2021

1. 01*

   $V_{cs}$ determination from $D\to K\ell \nu$

   W. G. Parrott🇬🇧 · Bipasha Chakraborty🇬🇧 · C. Bouchard🇬🇧 · C. T. H. Davies🇬🇧 · J. Koponen🇩🇪 · G. P. Lepage🇺🇸

   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, HPQCD present the results of a recently published, improved determination of $V_{cs}$. We discuss a new, precise determination of $D\to K$ scalar and vector form factors from a lattice calculation on eight different $N_f=2+1+1$ MILC gluon field ensembles using the HISQ action, including three with physical light quark masses. When combined with experimental results, we are able to extract $|V_{cs}|=0.9663(80)$ to a sub percent level of precision for the first time. This is achieved using three different methods, which each combine our form factors with different sets of experimental results in different ways, with the results in very good agreement. Our primary method is to use $q^2$-binned data for the differential decay rate, but we also calculate $V_{cs}$ from the total branching fraction and from the value $|V_{cs}|f_{+}(0)$, which is also quoted by some experiments.

   hep-latPoS(2022)·0 citations
2. 02*

   Charmonium-like resonances in coupled $D\bar{D}$-$D_s{\bar{D}}_s$ scattering

   S. Prelovsek🇸🇮 · S. Collins🇩🇪 · D. Mohler🇩🇪 · M. Padmanath🇩🇪 · S. Piemonte

   Charmonium-like resonances and bound states with isospin zero and $J^{PC}=0^{++},1^{--},2^{++},3^{--}$ are extracted on the lattice. Coupled $D\bar{D}$ and $D_s{\bar{D}}_s$ scattering suggests three charmonium-like states with $J^{PC}=0^{++}$ in addition to ${\chi }_{c0}(1P)$: a so far unobserved $D\bar{D}$ bound state just below threshold, a conventional resonance likely related to ${\chi }_{c0}(3860)/{\chi }_{c0}(2P)$ and a narrow resonance just below the $D_s{\bar{D}}_s$ threshold with a large coupling to $D_s{\bar{D}}_s$ likely related to $X(3915)/{\chi }_{c0}(3930)$. One-channel $D\bar{D}$ scattering renders resonances and bound states with $J^{PC}=1^{--},2^{++},3^{--}$ related to the observed conventional charmonia. Lattice QCD ensembles from the CLS consortium with $m_{\pi }\simeq 280$ MeV are utilized.

   hep-lathep-phPoS(2022)·3 citations
3. 03*

   Higher partial wave contamination in finite-volume formulae for 1-to-2 transitions

   Maxwell T. Hansen🇬🇧 · Toby Peterken🇬🇧

   It is common practice to truncate the finite-volume formula for $K\to \pi \pi$, and other one-to-two transitions, to only include the lowest partial wave, as in the original derivation by Lellouch and Lüscher. However, as the precision of lattice calculations increases, it may become important to asses the systematic effect of this approximation. With this motivation, we compare the $S$-wave-only ($\ell =0$) results with those truncated at the next lowest value of angular momentum.

   hep-latPoS(2022)·1 citation
4. 04*

   Comparison of lattice QCD results for inclusive semi-leptonic decays of $B$ mesons with the OPE

   Paolo Gambino🇮🇹 · Shoji Hashimoto🇯🇵 · Sandro Mächler

   A recently proposed approach to compute the inclusive semi-leptonic decay rate on the lattice allows for the calculation of various quantities (differential distributions and moments) in different subchannels. We systematically compare the lattice QCD results for an unphysically light bottom quark with OPE-based predictions, including leading order perturbative and $\mathcal{O}\left(1/m^3\right)$ power corrections, and explore possible strategies to decrease the systematic uncertainty.

   ↳ hep-phhep-latPoS(2022)·5 citations
5. 05*

   Slope of the topological charge, proton spin and $0^{-+}$ pseudoscalar di-gluonia spectra

   Stephan Narison (LUPM-CNRS-Montpellier-FR and iHEPMAD-Antananarivo-MG)🇫🇷

   We discuss the topics mentioned in the title by scrutinizing and improving the $0^{-+}$ di-gluonia sum rules within the standard SVZ-expansion at N2LO without instantons. First, we reconsider the estimate of the slope of the topological charge ${\chi }^{\prime }(0)=24.3(3.4)$ MeV which imply $0.144(5)[\mathrm{data}:0.145(13)]$ for the first moment of the polarized proton structure function (proton spin) and $G_A^{(0)}=0.337(50)[\mathrm{data}=0.330(39)]$ for the singlet form factor of the axial current. Second, we work with high degree moments and parametrize the spectral function beyond the minimal duality ansatz: "One resonance plus QCD continuum" to get the $0^{-+}$ di-gluonia spectra. Then, we obtain three groups of gluonia: The familiar light ${\eta }_1$ [singlet gluon component of the ${\eta }^{\prime }(958)$] with $[M_{{\eta }_1},f_{{\eta }_1}]=[825,905(72)]$; The two new medium gluonia with $M_{P_{1a}}=1338(112)$ MeV and $[M_{P_{1b}}=1462(117)$ MeV or their mean $[M_{P_1},f_{P_1}]=[1397(81),594(144)]$ MeV which support the gluonium nature of the candidate $\eta (1405)$ and may bring a small gluon piece to the $\eta (1295)$; Their 1st radial excitations: $M_{P_{1a}^{\prime }}=1508(226)$ MeV and $M_{P_{1b}^{\prime }}=1553(139)$ MeV with their mean: $[M_{P_1^{\prime }},f_{P_1^{\prime }}]=[1541(118),205(282)]$ MeV which may be identified (up to some eventual mixings with $\bar{q}q$ states) with the $\eta (1475,1700)$ states; The heavy gluonium with : $[M_{P_2},f_{P_2}]=[2751(140),500(43)]$ MeV comparable with the lattice results. One can remark the (natural) one to one correspondence between the pseudoscalar gluonia and their chiral scalar analogue from Ref.1: $\sigma (1)\to {\eta }_1;G_1(1.55)\to P_1;[{\sigma }^{\prime }(1.1),G^{\prime }(1.56)]\to P_{1a,1b}^{\prime };G_2(3)\to P_2$ which is mainly due to the importance of QCD PT in the sum rule analysis that are almost equal in these two channels. Results for the spectra are in Table 2.

   ↳ hep-phhep-exhep-latNPA(2022)·8 citations
6. 06*

   Nuclear two point correlation functions on a quantum-computer

   Alessandro Baroni🇺🇸 · Joseph Carlson🇺🇸 · Rajan Gupta🇺🇸 · Andy C. Y. Li🇺🇸 · Gabriel N. Perdue🇺🇸 · Alessandro Roggero🇺🇸

   The calculation of dynamic response functions is expected to be an early application benefiting from rapidly developing quantum hardware resources. The ability to calculate real-time quantities of strongly-correlated quantum systems is one of the most exciting applications that can easily reach beyond the capabilities of traditional classical hardware. Response functions of fermionic systems at moderate momenta and energies corresponding roughly to the Fermi energy of the system are a potential early application because the relevant operators are nearly local and the energies can be resolved in moderately short real time, reducing the spatial resolution and gate depth required. This is particularly the case in quasielastic electron and neutrino scattering from nuclei, a topic of great interest in the nuclear and particle physics communities and directly related to experiments designed to probe neutrino properties. In this work we use current quantum hardware and error mitigation protocols to calculate response functions for a highly simplified nuclear model through calculations of a 2-point real time correlation function for a modified Fermi-Hubbard model in two dimensions with three distinguishable nucleons on four lattice sites.

   ↳ quant-phhep-latnucl-thPRD(2022)·41 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.