Thu·Aug 17, 2017Thursday·August 17, 2017

1. 01*

   A combined analysis of PandaX, LUX, and XENON1T experiments within the framework of dark matter effective theory

   Zuowei Liu🇨🇳 · Yushan Su🇨🇳 · Yue-Lin Sming Tsai🇹🇼 · Bingrong Yu🇨🇳 · Qiang Yuan🇨🇳

   Weakly interacting massive particles are a widely well-probed dark matter candidate by the dark matter direct detection experiments. Theoretically, there are a large number of ultraviolet completed models that consist of a weakly interacting massive particle dark matter. The variety of models makes the comparison with the direct detection data complicated and often non-trivial. To overcome this, in the non-relativistic limit, the effective theory was developed in the literature which works very well to significantly reduce the complexity of dark matter-nucleon interactions and to better study the nuclear response functions. In the effective theory framework for a spin-1/2 dark matter, we combine three independent likelihood functions from the latest PandaX, LUX, and XENON1T data, and give a joint limit on each effective coupling. The astrophysical uncertainties of the dark matter distribution are also included in the likelihood. We further discuss the isospin violating cases of the interactions. Finally, for both dimension-five and dimension-six effective theories above the electroweak scale, we give updated limits of the new physics mass scales.

   hep-phastro-ph.COastro-ph.HEhep-ex+1JHEP(2017)·24 citations
2. 02*

   Threshold and jet radius joint resummation for single-inclusive jet production

   Xiaohui Liu🇨🇳 · Sven-Olaf Moch🇩🇪 · Felix Ringer🇺🇸

   We present the first threshold and jet radius jointly resummed cross section for single-inclusive hadronic jet production. We work at next-to-leading logarithmic accuracy and our framework allows for a systematic extension beyond the currently achieved precision. Longstanding numerical issues are overcome by performing the resummation directly in momentum space within Soft Collinear Effective Theory. We present the first numerical results for the LHC and observe an improved description of the available data. Our results are of immediate relevance for LHC precision phenomenology including the extraction of parton distribution functions and the QCD strong coupling constant.

   hep-phhep-exnucl-exnucl-thPRL(2017)·66 citations
3. 03*

   A New Look at the $Y$ Tetraquarks and ${\Omega }_c$ Baryons in the Diquark Model

   Ahmed Ali🇩🇪 · Luciano Maiani🇨🇭 · Anatoly V. Borisov🇷🇺 · Ishtiaq Ahmed🇵🇰 · M. Jamil Aslam🇵🇰 · Alexander Ya. Parkhomenko🇷🇺 · Antonio D. Polosa🇮🇹 · Abdur Rehman🇵🇰

   We analyze the hidden charm $P$-wave tetraquarks in the diquark model, using an effective Hamiltonian incorporating the dominant spin-spin, spin-orbit and tensor interactions. We compare with other $P$-wave system such as $P$-wave charmonia and the newly discovered ${\Omega }_c$ baryons, analysed recently in this framework. Given the uncertain experimental situation on the $Y$ states, we allow for different spectra and discuss the related parameters in the diquark model. In addition to the presently observed ones, we expect many more states in the supermultiplet of $L=1$ diquarkonia, whose $J^{PC}$ quantum numbers and masses are worked out, using the parameters from the currently preferred $Y$-states pattern. The existence of these new resonances would be a decisive footprint of the underlying diquark dynamics.

   hep-phhep-exEPJC(2018)·66 citations
4. 04*

   Testing the electroweak phase transition in scalar extension models at lepton colliders

   Qing-Hong Cao🇨🇳 · Fa Peng Huang🇨🇳 · Ke-Pan Xie🇨🇳 · Xinmin Zhang🇨🇳

   We study the electroweak phase transition in three scalar extension models beyond the Standard Model. Assuming new scalars are decoupled at some heavy scale, we use the covariant derivative expansion method to derive all of the dimension-6 effective operators, whose coefficients are highly correlated in a specific model. We provide bounds to the complete set of dimension-6 operators by including the electroweak precision test and recent Higgs measurements. We find that the parameter space of strong first-order phase transitions (induced by the $|H{|}^6$ operator) can be probed extensively in $Zh$ production at future electron-positron colliders.

   hep-phCPC(2018)·48 citations
5. 05*

   Hidden Charm Pentaquark $P_c(4380)$ and Doubly Charmed Baryon ${\Xi }_{cc}^{\ast }(4380)$ as Hadronic Molecule States

   Yuki Shimizu🇯🇵 · Masayasu Harada🇯🇵

   We study hadronic molecular states in a coupled system of $J/\psi N-{\Lambda }_c{\bar{D}}^{(\ast )}-{\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$ in $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ channel, using the complex scaling method combined with the Gaussian expansion method. We construct the potential including one pion exchange and one $D^{(\ast )}$ meson exchange with $S$-wave orbital angular momentum. We find that the both mass and width of the pentaquark $P_c(4380)$ can be reproduced within a reasonable parameter region, and that its main decay mode is ${\Lambda }_c{\bar{D}}^{\ast }$. We extend our analysis to a coupled system of ${\Lambda }_c{D}^{(\ast )}-{\Sigma }_c^{(\ast )}{D}^{(\ast )}$ in $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ channel. We find that there exists a doubly charmed baryon of $ccqq\bar{q}$ type as a hadronic molecule, the mass and width of which are quite close to those of $P_c(4380)$.

   hep-phnucl-thPRD(2017)·46 citations
6. 06*

   Dimension-six operators in Higgs pair production via vector-boson fusion at the LHC

   Ling Liu-Sheng🇨🇳 · Zhang Ren-You🇨🇳 · Ma Wen-Gan🇨🇳 · Li Xiao-Zhou🇨🇳 · Guo Lei🇨🇳 · Wang Shao-Ming🇨🇳

   The effective Lagrangian formalism provides a way to study the new physics effects at the electroweak scale. We study the Higgs pair production via the vector-boson fusion (VBF) at the Large Hadron Collider within the framework of the effective field theory. The effects from the dimension-six operators involved in the VBF Higgs pair production, particularly ${\mathcal{O}}_{\Phi ,2}$ and ${\mathcal{O}}_{\Phi ,3}$ which are relevant to the triple Higgs self-coupling, on the integrated cross section and various kinematic distributions are investigated. We find that the distributions of Higgs pair invariant mass, Higgs transverse momentum and rapidity are significantly altered by the operators ${\mathcal{O}}_{\Phi ,2}$ and ${\mathcal{O}}_{\Phi ,3}$. These features are helpful in disentangling the contributions from the operators ${\mathcal{O}}_{\Phi ,2}$ and ${\mathcal{O}}_{\Phi ,3}$ in triple Higgs self-coupling. We also provide the 5$\sigma$ discovery and 3$\sigma$ exclusion limits for the coefficients of ${\mathcal{O}}_{\Phi ,2}$ and ${\mathcal{O}}_{\Phi ,3}$ by measuring the VBF Higgs pair production process including the sequential $H\to b\bar{b}$ decays at the $14\mathrm{TeV}$ LHC.

   hep-phPRD(2017)·8 citations
7. 07*

   Global Analysis of Charmless $B$ Decays into Two Vector Mesons in Soft-Collinear Effective Theory

   Chao Wang🇨🇳 · Si-Hong Zhou🇨🇳 · Ying Li🇨🇳 · Cai-Dian Lu🇨🇳

   Under the framework of soft-collinear effective theory, we analyze the charmless $B\to VV$ decays in a global way at leading power in $1/m_b$ and leading order in ${\alpha }_s$ with $V$ denoting a light vector meson. In the flavor SU(3) symmetry, decay amplitudes for the 28 decay modes are expressed in terms of 8 nonperturbative parameters. With 35 experimental results, we fit these 8 nonperturbative parameters. Annihilation contributions are neglected due to power suppression in the $m_b\to \infty$ limit, so we include in the fit the nonperturbative charm penguins, which will play an important role in understanding the direct CP asymmetries. Charming penguins are also responsible for the large transverse polarizations of penguin-dominated and color-suppressed decays. With the best fitted parameters, we calculate all possible physical observables of 28 decay modes, including branching fractions, direct CP asymmetries, and the complete set of polarization observables. Most of our results are compatible with the present experimental data when available, while the others can be examined on the ongoing LHCb experiment and the forthcoming Belle-II experiment. Moreover, the agreements and differences with results in QCD factorization and perturbative QCD approach are also discussed. A few observables are suggested to discriminate these different approaches.

   hep-phPRD(2017)·34 citations
8. 08*

   Damping of an oscillating scalar field indirectly coupled to a thermal bath

   Erwin H. Tanin🇰🇷 · Ewan D. Stewart🇰🇷

   The damping process of a homogeneous oscillating scalar field that indirectly interacts with a thermal bath through a mediator field is investigated over a wide range of model parameters. We consider two types of mediator fields, those that can decay to the thermal bath and those that are individually stable but pair annihilate. The former case has been extensively studied in the literature by treating the damping as a local effect after integrating out the assumed close-to-equilibrium mediator field. The same approach does not apply if the mediator field is stable and freezes out of equilibrium. To account for the latter case, we adopt a non-local description of damping that is only meaningful when we consider full half-oscillations of the field being damped. The damping rates of the oscillating scalar field and the corresponding heating rate of the thermal bath in all bulk parameter regions are calculated in both cases, corroborating previous results in the direct decay case. Using the obtained results, the time it takes for the amplitude of the scalar field to be substantially damped is estimated.

   hep-phastro-ph.COJCAP(2017)·13 citations
9. 09*

   Baryon number fluctuations and QCD phase structure

   Guo-yun Shao🇨🇳 · Zhan-duo Tang🇨🇳 · Xue-yan Gao🇨🇳 · Wei-bo He🇨🇳

   We investigate the phase structure of strongly interacting matter and baryon number fluctuations in the Polyakov loop improved Nambu--Jona-Lasinio (PNJL) model. The calculation shows that both the chiral and deconfinement transitions, as well as their coincidence and separation determine the basic QCD phase structure. The contour maps and the three-dimensional diagrams of the net-baryon kurtosis and skewness present well the trace of QCD phase structure. Comparing with the experimental data, we find that the existence of a critical end point (CEP) of chiral transition is crucial to explain the non-monotonic energy dependence and the large deviation from Poisson baseline of net-proton kurtosis. In particular, the relation between the chiral and deconfinement transitions in the crossover region is also reflected by the baryon number fluctuations. This study shows that the measurements of higher moments of multiplicity distributions of conserved charges are powerful to investigate the criticality and even the chiral and deconfinement transitions in the crossover region.

   hep-phEPJC(2018)·33 citations
10. 10*

    Probing Direct and Indirect Unitarity Violation in Future Accelerator Neutrino Facilities

    Jian Tang🇨🇳 · Yibing Zhang🇨🇳 · Yu-Feng Li🇨🇳

    The possible existence of light and heavy sterile neutrinos may give rise to direct and indirect unitarity violation of the $3\times 3$ lepton mixing matrix respectively. In the current work we study the potential of future accelerator neutrino facilities in probing the unitarity violation effects. Taking DUNE, T2HK and a low-energy Neutrino Factory (LENF) as working examples of future accelerator neutrino facilities, we study the distinct effects of direct and indirect unitarity violation on the discovery reach of the leptonic CP violation and precision measurements of ${\theta }_{23}$ in the three neutrino framework. In addition, constraints on the additional mixing parameters of direct and indirect unitarity violation are also discussed. Finally, we stress that the combination of experiments with different oscillation channels, different neutrino beams and different detector techniques will be an effective solution to the parameter degeneracy problem and give the robust measurement of leptonic CP violation even if the direct and indirect unitarity violation are taken into account.

    hep-phPLB(2017)·30 citations
11. 11*

    New model of the kaon regeneration

    Valeriy Nazaruk🇷🇺

    It is shown that in the standard model of $K_S^0$ regeneration a system of noncoupled equations of motion is used instead of the coupled ones. A model alternative to the standard one is proposed. The calculation performed by means of diagram technique agrees with that based on exact solution of equations of motion.

    hep-phCPC(2018)·2 citations
12. 12*

    Features of the QCD phase diagram from small, noisy, fluctuating systems

    Eduardo S. Fraga🇧🇷 · Maurício Hippert🇧🇷

    Current heavy-ion collision experiments might lead to the discovery of a first-order chiral symmetry breaking phase-transition line, ending in a second-order critical point. Nevertheless, the extraction of information about the equilibrium thermodynamic properties of baryonic matter from the highly dynamic, small, noisy and fluctuating environment formed in such collisions is an extremely challenging task. We address some of the limitations present in the experimental search for the QCD critical point.

    hep-phnucl-thActa Phys.Polon.Supp.(2017)·0 citations
13. 13*

    Opening up the QCD axion window

    Prateek Agrawal🇺🇸 · Gustavo Marques-Tavares🇺🇸 · Wei Xue🇺🇸

    We present a new mechanism to deplete the energy density of the QCD axion, making decay constants as high as $f_a\simeq 10^{17}\mathrm{GeV}$ viable for generic initial conditions. In our setup, the axion couples to a massless dark photon with a coupling that is moderately stronger than the axion coupling to gluons. Dark photons are produced copiously through a tachyonic instability when the axion field starts oscillating, and an exponential suppression of the axion density can be achieved. For a large part of the parameter space this dark radiation component of the universe can be observable in upcoming CMB experiments. Such dynamical depletion of the axion density ameliorates the isocurvature bound on the scale of inflation. The depletion also amplifies the power spectrum at scales that enter the horizon before particle production begins, potentially leading to axion miniclusters.

    hep-phJHEP(2018)·143 citations
14. 14*

    Charge symmetry breaking in light $\Lambda$ hypernuclei

    Avraham Gal🇮🇱 · Daniel Gazda🇸🇪

    Charge symmetry breaking (CSB) is particularly strong in the A=4 mirror hypernuclei ${}_{\Lambda }^4$H--${}_{\Lambda }^4$He. Recent four-body no-core shell model calculations that confront this CSB by introducing $\Lambda$-${\Sigma }^0$ mixing to leading-order chiral effective field theory hyperon-nucleon potentials are reviewed, and a shell-model approach to CSB in p-shell $\Lambda$ hypernuclei is outlined.

    ↳ nucl-thhep-phnucl-exJ.Phys.Conf.Ser.(2018)·7 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.