Tue·Jan 15, 2019Tuesday·January 15, 2019

1. 01*

   The LFV decays of Z boson in Minimal R-symmetric Supersymmetric Standard Model

   Ke-Sheng Sun🇨🇳 · Jian-Bin Chen🇨🇳 · Xiu-Yi Yang🇨🇳 · Sheng-Kai Cui🇨🇳

   A future $Z$-factory will offer the possibility to study rare $Z$ decays $Z\to l_1{l}_2$, as those leading to Lepton Flavor Violation final states. In this work, by taking account of the constraints from radiative two body decays $l_2\to l_1\gamma$, we investigate the Lepton Flavor Violation decays $Z\to l_1{l}_2$ in the framework of Minimal R-symmetric Supersymmetric Standard Model with two benchmark points from already existing literatures. The flavor violating off-diagonal entries ${\delta }^{12}$, ${\delta }^{13}$ and ${\delta }^{23}$ are constrained by the current experimental bounds of $l_2\to l_1\gamma$. Considering recent experimental constraints, we also investigate Br($Z\to l_1{l}_2$) as a function of $M_D^W$. The numerical results show that the theoretical prediction of Br($Z\to l_1{l}_2$) in MRSSM are several orders of magnitude below the current experimental bounds. The Lepton Flavor Violation decays $Z\to e\tau$ and $Z\to \mu \tau$ may be promising to be observed in future experiment.

   hep-phCPC(2019)·12 citations
2. 02*

   The LFV decays $B_{d,s}^0\to e\mu (e\tau ,\mu \tau )$ with one neutral singlet scalar

   Ke-Sheng Sun🇨🇳 · Xiu-Yi Yang🇨🇳

   Taking account of the constraint from radiative two body decays $l_i\to l_j\gamma$, we investigate the Lepton Flavor Violation decays $B_q^0\to \overline{l_l}{l}_k$ in the framework of the minimal extension of the Standard Model with one neutral singlet scalar. The couplings $C_{e\mu }$, $C_{e\tau }$ and $C_{\mu \tau }$ between the different generation leptons and scalar $S^0$ are constrained by the current bounds of $l_i\to l_j\gamma$. The numerical results show that the theoretical prediction of $B_q^0\to \overline{l_l}{l}_k$ strongly depend on the couplings $C_{qb}$ ($q=dors$) between down type quarks and new scalar. The contributions from couplings $C_{uc}$, $C_{ut}$ and $C_{ct}$ between up type quark and new scalar are less dominant.

   hep-phMod.Phys.Lett.A(2018)·2 citations
3. 03*

   One loop correction to $Z\to \nu \nu$ in the Minimal R-symmetric Supersymmetric Standard Model

   Ke-Sheng Sun🇨🇳 · Jian-Bin Chen🇨🇳 · Xiu-Yi Yang🇨🇳 · Hai-Bin Zhang🇨🇳

   We analyze the one loop correction to $Z\to \nu \nu$ decay in framework of Minimal R-symmetric Supersymmetric Standard Model(MRSSM) in detail with normal and inverse neutrino mass orderings, as a function of $\tan \beta$, Dirac mass parameters $M_D^W$ and ${\mu }_u({\mu }_d)$, slepton mass $m_l$ that parameterize the mass matrices. The numerical results indicate that the branching ratio for $Z\to \nu \nu$ decay is compatible with the experimental measurement and the SM expectation at $2\sigma$ level. For inverse neutrino mass ordering, the prediction exceeds the SM expectation at $1\sigma$ level. The prediction on $Br(Z\to \nu \nu )$ increases proportionally to $\tan \beta$ and inversely proportionally to $m_l$. For normal neutrino mass ordering, the peak value of the prediction on $Br(Z\to \nu \nu )$ exceeds the SM expectation at $1\sigma$ level.

   hep-phMod.Phys.Lett.A(2019)·2 citations
4. 04*

   Revisit to electrical and thermal conductivities, Lorenz number and Knudsen number in thermal QCD in a strong magnetic field

   Shubhalaxmi Rath🇮🇳 · Binoy Krishna Patra🇮🇳

   We have explored how the electrical (${\sigma }_{\mathrm{el}}$) and thermal ($\kappa$) conductivities in a thermal QCD medium get affected in weak-momentum anisotropies arising either due to a strong magnetic field or due to asymptotic expansion. This study facilitates to understand the longevity of strong magnetic field through ${\sigma }_{el}$, Lorenz number in Wiedemann-Franz law, and the validity of equilibrium by the Knudsen number. We calculate the conductivities by solving relativistic Boltzmann transport equation in relaxation-time approximation within quasiparticle model at finite T and strong B. We have found that ${\sigma }_{el}$ and $\kappa$ get enhanced in a magnetic field-driven anisotropy, but ${\sigma }_{el}$ decreases with temperature, opposite to its faster increase in expansion-driven anisotropy. Whereas $\kappa$ increases slowly with temperature, contrary to its rapid increase in expansion-driven anisotropy. The above findings are broadly attributed to three factors: the stretching and squeezing of distribution function in anisotropies generated by the magnetic field and asymptotic expansion, respectively, the dispersion relation and resulting phase-space factor, the relaxation-time in absence and presence of strong magnetic field. So ${\sigma }_{\mathrm{el}}$ extracts the time-dependence of magnetic field, which decays slower than in vacuum but expansion-driven anisotropy makes the decay faster. The variation in $\kappa$ transpires that Knudsen number decreases with T but expansion-driven anisotropy reduces its value and magnetic field-driven anisotropy raises its value but to less than one, thus the system can still be in equilibrium. The ratio, $\kappa /{\sigma }_{el}$ in magnetic field-driven anisotropy increases linearly with temperature but with a value smaller than in expansion-driven anisotropy. Thus the Lorenz number can make the distinction between different anisotropies.

   hep-phhep-thnucl-thPRD(2019)·55 citations
5. 05*

   First results of EPOS-HQ model for open heavy flavor production in A-A collission at RHIC and LHC

   Pol Bernard Gossiaux🇫🇷 · Joerg Aichelin🇫🇷 · Benjamin Guiot🇨🇱 · Iurii Karpenko🇫🇷 · Vitalii Ozvenchuk🇵🇱 · Tanguy Pierog🇩🇪 · Jan Steinheimer🇩🇪 · Klaus Werner🇫🇷

   The EPOS-HQ model is a framework designed for predicting heavy-flavor observables both in p-p, p-A and A-A collisions. It results from the integration of the MC${@}_s$HQ and EPOS3 codes and should supersede predictions made with each of these two. In this contribution, we briefly present the new ingredients of the EPOS-HQ model as well as some preliminary results. From the comparison with experimental data, we derive some direction of improvement for the near future.

   hep-phhep-exnucl-thPoS(2019)·4 citations
6. 06*

   Semileptonic and nonleptonic decays of $D$ into tensor mesons with light-cone sum rule

   S. Momeni🇮🇷 · R. Khosravi🇮🇷 · S. Ghaziasgar🇮🇷

   Form factors of $D$ decays into $J^{PC}=2^{++}$ tensor mesons are calculated in the light-cone sum rules approach up to twist-4 distribution amplitudes of the tensor meson. The masses of the tensor mesons are comparable to that of the charm quark mass $m_c$; therefore all terms including powers of $m_T/m_c$ are kept out in the expansion of the two-particle distribution amplitude $⟨T|{\bar{q}}_{1\alpha }(x)q_{2\delta }(0)|0⟩$. Branching ratios of the semileptonic $D\to T\mu {\bar{\nu }}_{\mu }$ decays and nonleptonic $D\to TP(P=K,\pi )$ decays are taken into consideration. A comparison is also made between our results and predictions of other methods and the existing experimental values for the nonleptonic case. The semileptonic branching ratios are typically of the order of $10^{-5}$, and the nonleptonic ones show better agreement with the experimental data in comparison to the Isgur-Scora-Grinstein-Wise predictions.

   hep-phPRD(2019)·2 citations
7. 07*

   Tetraquark-adequate formulation of QCD sum rules

   Wolfgang Lucha🇦🇹 · Dmitri Melikhov🇦🇹 · Hagop Sazdjian🇫🇷

   We study details of QCD sum rules à la Shifman-Vainshtein-Zakharov for exotic tetraquark states. We point out that duality relations for correlators involving exotic currents have fundamental differences compared with the duality relations for the correlators of bilinear quark currents: namely, the $O(1)$ and $O({\alpha }_s)$ [${\alpha }_s$ the strong coupling constant] terms in the operator product expansion for the exotic correlators exactly cancel against the contributions of the two-meson states on the hadron side of QCD sum rules. As a result, the tetraquark properties turn out to be related to the specific non-factorizable parts of the exotic Green functions; the relevant non-factorizable diagrams start at order $O({\alpha }_s^2)$.

   hep-phPRD(2019)·39 citations
8. 08*

   Dark matter and $B$-meson anomalies in a flavor dependent gauge symmetry

   Parada T. P. Hutauruk🇰🇷 · Takaaki Nomura🇰🇷 · Hiroshi Okada🇰🇷 · Yuta Orikasa🇨🇿

   A possibility of explaining the anomalies in the semileptonic $B$-meson decay $B\to K^{\ast }\mu \bar{\mu }$ has been explored in the framework of the gauged $U(1{)}_{\mu -\tau }$ symmetry. Apart from the muon anomalous magnetic moment and neutrino sector, we formulate the model starting with a valid Lagrangian and consider the constraints from the neutral meson mixings, the bounds on direct detection and the relic density of the bosonic dark matter candidate augmented to collider constraints. We search the parameter space, which accommodates the size of the anomaly of the $B\to K^{\ast }\mu \bar{\mu }$ decay, to satisfy all experimental constraints. We found the allowed region on the plane of the dark matter and $Z^{\prime }$ masses is a rather narrow compared to the previous analysis.

   hep-phPRD(2019)·25 citations
9. 09*

   Quasi-two-body decays $B\to D{K}^{\ast }(892)\to DK\pi$ in the perturbative QCD approach

   Ai-Jun Ma🇨🇳 · Wen-Fei Wang🇨🇳 · Ya Li🇨🇳 · Zhen-Jun Xiao🇨🇳

   We study the quasi-two-body decays $B\to D{K}^{\ast }(892)\to DK\pi$ by employing the perturbative QCD approach. The two-meson distribution amplitudes \Phi_{K\pi}^{\text{P-wave}} are adopted to describe the final state interactions of the kaon-pion pair in the resonance region. The resonance line shape for the $P$-wave $K\pi$ component $K^{\ast }(892)$ in the time-like form factor $F_{K\pi }(s)$ is parameterized by the relativistic Breit-Wigner function. For most considered decay modes, the theoretical predictions for their branching ratios are consistent with currently available experimental measurements within errors. We also disscuss some ratios of the branching fractions of the concerned decay processes. More precise data from LHCb and Belle-II are expected to test our predictions.

   hep-phEPJC(2019)·22 citations
10. 10*

    Top-quark pair hadroproduction at next-to-next-to-leading order in QCD

    Stefano Catani🇮🇹 · Simone Devoto🇨🇭 · Massimiliano Grazzini🇨🇭 · Stefan Kallweit🇮🇹 · Javier Mazzitelli🇨🇭 · Hayk Sargsyan🇨🇭

    We report on a new calculation of the next-to-next-to-leading order (NNLO) QCD radiative corrections to the inclusive production of top-quark pairs at hadron colliders. The calculation is performed by using the $q_T$ subtraction formalism to handle and cancel infrared singular contributions at intermediate stages of the computation. We present numerical results for the total cross section in $pp$ collisions at $\sqrt{s}=8$ TeV and $13$ TeV, and we compare them with those obtained by using the publicly available numerical program Top++. Our computation represents the first complete application of the $q_T$ subtraction formalism to the hadroproduction of a colourful high-mass system at NNLO.

    hep-phhep-exPRD(2019)·168 citations
11. 11*

    Rotation-invariant observables as Density Matrix invariants

    Margarita Gavrilova🇷🇺 · Oleg Teryaev🇷🇺

    It is shown that general dilepton angular distribution (with parity violating terms taking into account) in vector particle decays can be described through a set of five SO(3) rotational-invariant observables. These observables are derived as invariants of the spacial part of the hadronic tensor (density matrix) expressed in terms of angular coefficients. The restrictions on the invariants following from the positivity of the hadronic tensor are obtained. Special cases of SO(2) rotations are considered. Calculation of invariants for available data on Z and J/{\psi} decays is performed.

    hep-phPRD(2019)·13 citations
12. 12*

    Chromopolarizability of charmonium and $\pi \pi$ final state interaction revisited

    Yun-Hua Chen🇨🇳

    The chromopolarizability of a quarknonium describes the quarknonium's interaction with soft gluonic fields and can be measured in the heavy quarkonium decays. Within the framework of dispersion theory which consider the $\pi \pi$ final state interaction (FSI) model-independently, we analyze the transition ${\psi }^{\prime }\to J/\psi {\pi }^{+}{\pi }^{-}$ and obtain the chromopolarizability ${\alpha }_{{\psi }^{\prime }\psi }$ and the parameter $\kappa$. It is found that the $\pi \pi$ FSI plays an important role in extracting the chromopolarizability from the experimental data. The obtained chromopolarizability with the FSI is reduced to about 1/2 of that without the FSI. With the FSI, we determine the chromopolarizability $|{\alpha }_{{\psi }^{\prime }\psi }|=(1.44\pm 0.02)$ GeV${}^{-3}$ and the parameter $\kappa =0.139\pm \mathrm{0.005.}$ Our results could be useful in studying the interactions of charmonium with light hadrons.

    hep-phhep-exhep-latnucl-thAdv.High Energy Phys.(2019)·9 citations
13. 13*

    Impact of magnetic-field fluctuations on measurements of the chiral magnetic effect in collisions of isobaric nuclei

    Xin-Li Zhao🇨🇳 · Guo-Liang Ma🇨🇳 · Yu-Gang Ma🇨🇳

    We investigate the properties of electromagnetic fields in isobaric ${}_{44}^{96}\text{Ru}+{}_{44}^{96}\text{Ru}$ and ${}_{40}^{96}\text{Zr}+{}_{40}^{96}\text{Zr}$ collisions at $\sqrt{s}$ = 200 GeV by using a multiphase transport model, with special emphasis on the correlation between magnetic field direction and participant plane angle ${\Psi }_2$ (or spectator plane angle ${\Psi }_2^{\mathrm{SP}}$), i.e. $⟨\cos 2({\Psi }_B-{\Psi }_2)⟩$ [or $⟨\cos 2({\Psi }_B-{\Psi }_2^{\mathrm{SP}})⟩$]. We confirm that the magnetic fields of ${}_{44}^{96}\text{Ru}+{}_{44}^{96}\text{Ru}$ collisions are stronger than those of ${}_{40}^{96}\text{Zr}+{}_{40}^{96}\text{Zr}$ collisions due to their larger proton fraction. We find that the deformation of nuclei has a non-negligible effect on $⟨\cos 2({\Psi }_B-{\Psi }_2)⟩$ especially in peripheral events. Because the magnetic-field direction is more strongly correlated with ${\Psi }_2^{\mathrm{SP}}$ than with ${\Psi }_2$, the relative difference of the chiral magnetic effect observable with respect to ${\Psi }_2^{\mathrm{SP}}$ is expected to be able to reflect much cleaner information about the chiral magnetic effect with less influences of deformation.

    hep-phnucl-exnucl-thPRC(2019)·40 citations
14. 14*

    Neutrino Mass Matrix in a gauge group $SU(2{)}_L\times U(1{)}_e\times U(1{)}_{\mu }\times U(1{)}_{\tau }$

    Fayyazuddin🇵🇰

    The electroweak unification group $G\equiv SU(2{)}_L\times U(1{)}_e\times U(1{)}_{\mu }\times U(1{)}_{\tau }$ in which each fermion multiplet has its own $U(1)$ factor was proposed in 1986 to get the neutrino mass matrix. In this paper, the gauge group G is restricted to lepton section only, leaving quark multiplets as in the standard model. In addition to lepton multiplets $L_e$, $L_{\mu }$ and $L_{\tau }$, there are three $SU(2)$singlet right handed neutrinos $N_R^{(i)}$'s. WIth the breaking of G to $SU(2{)}_L\times U(1)$, the right handed neutrinos acquire heavy Majorana masses. Three heavy right handed neutrinos $N_R^{(i)}$'s are available to generate a $3\times 3$ non-diagonal neutrino mass matrix in terms of three Yukawa couplings $h_1^{(2)}$, $h_2^{(3)}$, $h_3^{(1)}$ of the Higgs scalar doublet to $L_e$, $L_{\mu }$, $L_{\tau }$ with $N_R^{(1)}$, $N_R^{(2)}$ and $N_R^{(3)}$ respectively. Three Yukawa couplings can be arranged and expressed in terms of masses $m_e$, $m_{\mu }$, $m_{\tau }$ in three different ways to obtain the results of interest for Case 1: (${\nu }_e\to {\nu }_{\tau }$); Case 2: (${\nu }_e\to {\nu }_{\mu }$); Case 3: (${\nu }_{\mu }\to {\nu }_{\tau }$). The results obtained for the three cases are compared with the experimental data from neutrino oscillations. Cases 1 and 2 are relevant for solar neutrino oscillations whereas Case 3 is relevant for atmospheric neutrino oscillations.

    hep-phInt.J.Mod.Phys.A(2019)·0 citations
15. 15*

    Extracting jet transport coefficient via single hadron and dihadron productions in high-energy heavy-ion collisions

    Man Xie🇨🇳 · Shu-Yi Wei🇫🇷 · Guang-You Qin🇨🇳 · Han-Zhong Zhang🇨🇳

    We study the suppressions of high transverse momentum single hadron and dihadron productions in high-energy heavy-ion collisions based on the framework of a next-to-leading-order perturbative QCD parton model combined with the higher-twist energy loss formalism.Our model can provide a consistant description for the nuclear modification factors of single hadron and dihadron productions in central and non-central nucleus-nucleus collisions at RHIC and the LHC energies. We quantitatively extract the value of jet quenching parameter $\hat{q}$ via a global ${\chi }^2$ analysis, and obtain $\hat{q}/T^3=4.1\sim 4.4$ at $T=378$~MeV at RHIC and $\hat{q}/T^3=2.6\sim 3.3$ at $T=486$~MeV at the LHC, which are consistent with the results from JET Collaboration. We also provide the predictions for the nuclear modification factors of dihadron productions in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV and in Xe+Xe collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.44 TeV.

    hep-phnucl-thEPJC(2019)·42 citations
16. 16*

    Novel mechanism for electric quadrupole moment generation in relativistic heavy-ion collisions

    Xin-Li Zhao🇨🇳 · Guo-Liang Ma🇨🇳 · Yu-Gang Ma🇨🇳

    We present the spatial distributions of electromagnetic fields ($\mathbf{E}$ and $\mathbf{B}$) and electromagnetic anomaly $\mathbf{E}\cdot \mathbf{B}$ in Au+Au collisions at the RHIC energy $\sqrt{s}$=200 GeV based on a multi-phase transport model. A dipolar distribution of $\mathbf{E}\cdot \mathbf{B}$ is observed in non-central collisions. We find that the coupling of the $\mathbf{E}\cdot \mathbf{B}$ dipole and magnetic field $\mathbf{B}$ can induce an electric quadrupole moment which can further lead to the difference in elliptic flows between positive charged particles and negative charged particles through final interactions. The centrality dependence of the density of $\mathbf{E}\cdot \mathbf{B}$ is similar to the trend of the slope parameter $r$ measured from the difference in elliptic flows between positive pions and negative pions by the STAR collaboration. Therefore, the novel mechanism for electric quadrupole moment generation can offer a new interpretation of the observed charge-dependent elliptic flow of pions, but without the formation of chiral magnetic wave.

    hep-phnucl-exnucl-thPLB(2019)·30 citations
17. 17*

    Conformal vector dark matter and strongly first-order electroweak phase transition

    Seyed Yaser Ayazi🇮🇷 · Ahmad Mohamadnejad🇮🇷

    We study a conformal version of the Standard Model (SM), which apart from SM sector, containing a $U_D(1)$ dark sector with a vector dark matter candidate and a scalar field (scalon). In this model the dark sector couples to the SM sector via a Higgs portal. The theory is scale-invariant in lowest order, therefore the spontaneous symmetry breaking of scale invariance entails the existence of a scalar particle, scalon, with vanishing zeroth-order mass. However, one-loop corrections break scale invariance, so they give mass to the scalon. Because of the scale invariance, our model is subjected to constraints which remove many of the free parameters. We put constraints to the two remaining parameters from the Higgs searches at the LHC, dark matter relic density and dark matter direct detection limits by PandaX-II. The viable mass region for dark matter is about 1-2 TeV. We also obtain the finite temperature one-loop effective potential of the model and demonstrate that finite temperature effects, for the parameter space constrained by dark matter relic density, induce a strongly first-order electroweak phase transition.

    hep-phJHEP(2019)·48 citations
18. 18*

    XEFT, the challenging path up the hill: dim = 6 and dim = 8

    Giampiero Passarino (Turin Univ)🇮🇹

    There is increasing need to assess the impact and the interpretation of dim = 6 and dim = 8 operators within the context of the Standard Model Effective Field Theory (SMEFT). The observational and mathematical consistency of a construct based on dim = 6 and dim = 8 operators is critically examined in the light of known theoretical results. The discussion is based on a general dim = 4 theory X and its effective extension, XEFT; it includes elimination of redundant operators and their higher order compensation, SMEFT in comparison with ultraviolet completions incorporating a proliferation of scalar and mixings, canonical normalization of effective field theories, gauge invariance and gauge fixing, role of tadpoles when constructing XEFT at NLO, heavy-light contributions to the low energy limit of theories containing bosons and fermions, one-loop matching, EFT fits and their interpretation and effective field theory interpretation of derivative-coupled field theories.

    hep-ph25 citations
19. 19*

    Accurate predictions for t-channel single top-quark production

    Rikkert Frederix🇩🇪

    Single top-quark production through the exchange of a t-channel W-boson is the main electroweak production mode for top quarks at the Large Hadron Collider. I discuss a recent development in the theoretical predictions for this process, in which t-channel single-top with an additional jet is combined, at NLO accuracy, with t-channel single top production, without the introduction of a merging scale.

    hep-ph0 citations
20. 20*

    On the kinematic limit of the charm production in fixed-target experiments with the intrinsic charm from the target

    Stefan Groote🇪🇪 · Sergey Koshkarev🇪🇪

    In this note we provide a detailed derivation of the kinematic limit of the charm production in fixed-target experiments with the intrinsic charm coming from the target. In addition, we discuss the first measurement of charm quark production in the fixed-target configuration at the LHC.

    hep-phnucl-th0 citations
21. 21*

    Electroweak phase transition via Dilaton in Two-Time Physics

    Vo Quoc Phong🇻🇳 · Dam Quang Nam🇻🇳

    The Two-time model (2T model) has six dimensions with two dimensions of time, has a Dilaton particle that makes the symmetry breaking differently from the Standard Model. Assuming a soft break of $SP(2,R)$ symmetry, the 2T extension can give a suitable picture of the matter-antimatter asymmetry by the Baryogenesis scenario. By reducing the 2T metric to the Minkowski metric (1T metric) and using a new form of Dilaton potential, we consider the electroweak phase transition picture in the 2T model with the Dilaton as a trigger. Our analysis shows that Electroweak Phase Transition (EWPT) is a first-order phase transition at the $200$ GeV scale, its strength is about $1-3.08$ and the mass of Dilaton is in the interval $[345,625]$ GeV. Therefore, the 2T-model indirectly suggests that extra-dimension can also be a source of EWPT.

    hep-phInt.J.Mod.Phys.A(2023)·2 citations
22. 22*

    The Bethe-Salpeter approach to bound states: from Euclidean to Minkowski space

    A. Castro🇧🇷 · E. Ydrefors🇧🇷 · W. de Paula🇧🇷 · T. Frederico🇧🇷 · J.H. de Alvarenga Nogueira🇧🇷 · P. Maris🇺🇸

    The challenge to obtain from the Euclidean Bethe--Salpeter amplitude the amplitude in Minkowski is solved by resorting to un-Wick rotating the Euclidean homogeneous integral equation. The results obtained with this new practical method for the amputated Bethe--Salpeter amplitude for a two-boson bound state reveals a rich analytic structure of this amplitude, which can be traced back to the Minkowski space Bethe--Salpeter equation using the Nakanishi integral representation. The method can be extended to small rotation angles bringing the Euclidean solution closer to the Minkowski one and could allow in principle the extraction of the longitudinal parton density functions and momentum distribution amplitude, for example.

    hep-phnucl-thJ.Phys.Conf.Ser.(2019)·6 citations
23. 23*

    A New Sensitivity Goal for Neutrino-less Double Beta Decay Experiments

    Vishnudath K. N.🇮🇳 · Sandhya Choubey🇮🇳 · Srubabati Goswami🇮🇳

    We study the implications of the Dark-LMA solution to the solar neutrino problem for neutrino-less double beta decay ($0\nu \beta \beta$ ). We show that while the predictions for the effective mass governing $0\nu \beta \beta$ remains unchanged for the inverted mass scheme, that for normal ordering becomes higher for the Dark-LMA parameter space and moves into the "desert region" between the two. This sets a new goal for sensitvity reach for the next generation experiments if no signal is found for the inverted ordering by the future search programmes.

    hep-phhep-exPRD(2019)·14 citations
24. 24*

    Scattering cross-section under external magnetic field using the optical theorem

    Snigdha Ghosh🇮🇳 · Vinod Chandra🇮🇳

    The cross-section for the lowest order $2\to 2$ elastic scattering between two charged scalars under external magnetic field mediated via a neutral scalar, has been computed in strong as well as weak magnetic field limits. This has been done by applying the optical theorem where the cross-section is expressed in terms of the imaginary parts of different one-loop graphs contributing to the forward scattering amplitudes. The modification in the amplitudes due to the external magnetic field has been done by means of replacing the charged scalar propagators with the Schwinger proper-time ones. Significant modifications of the cross-sections with respect to the vacuum cross-section are observed due to the external magnetic field.

    hep-phnucl-thEPJA(2020)·5 citations
25. 25*

    Master integrals for two-loop $C$-odd contribution to $e^{+}{e}^{-}\to {\ell }^{+}{\ell }^{-}$ process

    Roman N. Lee🇷🇺 · Kirill T. Mingulov🇷🇺

    We calculate two-loop master integrals for the process of heavy lepton pair production in $e^{+}{e}^{-}$ collisions. We consider the $C$-odd diagrams with three photons in the intermediate state and evaluate the corresponding families of the master integrals in the limit of zero electron mass. Our results for the master integrals are directly applicable in the whole physical region corresponding to the annihilation channel.

    hep-ph8 citations
26. 26*

    NNLO versus NLO multi-jet merging for top-pair production including electroweak corrections

    Michał Czakon🇩🇪 · Christian Gütschow🇬🇧 · Jonas M. Lindert🇬🇧 · Alexander Mitov🇬🇧 · Davide Pagani🇩🇪 · Andrew S. Papanastasiou🇬🇧 · Marek Schönherr🇨🇭 · Ioannis Tsinikos🇩🇪 · Marco Zaro🇳🇱

    In this proceedings we compare phenomenological predictions for differential distributions in top-quark pair production at the LHC. In particular we consider NNLO QCD fixed-order predictions and parton-level predictions based on NLO QCD multi-jet merging following the MEPS@NLO scheme. In both predictions NLO electroweak (EW) corrections are incorporated in different approximations. We focus on several transverse-momentum distributions and on the top-quark invariant mass distribution, both highly relevant for the ongoing physics program at the LHC. We discuss comparisons between the different considered approximations and their advantages and disadvantages for different distributions.

    hep-phhep-ex10 citations
27. 27*

    Radiative Production of Non-thermal Dark Matter

    Kunio Kaneta🇺🇸 · Yann Mambrini🇫🇷 · Keith A. Olive🇺🇸

    We compare dark matter production from the thermal bath in the early universe with its direct production through the decay of the inflaton. We show that even if dark matter does not possess a direct coupling with the inflaton, Standard Model loop processes may be sufficient to generate the correct relic abundance.

    hep-phPRD(2019)·91 citations
28. 28*

    Analyzing $\Xi (1620)$ in the molecule picture in the Bethe-Salpeter equation approach

    Zhen-Yang Wang🇨🇳 · Jing-Juan Qi🇨🇳 · Jing Xu🇨🇳 · Xin-Heng Guo🇨🇳

    In this work, we assume that the observed state $\Xi (1620)$ is a $s$-wave $\Lambda \bar{K}$ or $\Sigma \bar{K}$ bound state. Based on this molecule picture, we establish the Bethe-Salpeter equations for $\Xi (1620)$ in the ladder and instantaneous approximations. We solve the Bethe-Salpeter equations for the $\Lambda \bar{K}$ and $\Sigma \bar{K}$ systems numerically and find that the $\Xi (1620)$ can be explained as $\Lambda \bar{K}$ and $\Sigma \bar{K}$ bound states with $J^P=1/2^{-}$, respectively. Then we calculate the decay widths of $\Xi (1620)\to \Xi \pi$ in these two different molecule pictures systems, respectively.

    hep-phEPJC(2019)·13 citations
29. 29*

    The Transverse Energy-Energy Correlator in the Back-to-Back Limit

    AnJie Gao🇨🇳 · Hai Tao Li🇺🇸 · Ian Moult🇺🇸 · Hua Xing Zhu🇨🇳

    We present an operator based factorization formula for the transverse energy-energy correlator (TEEC) hadron collider event shape in the back-to-back (dijet) limit. This factorization formula exhibits a remarkably symmetric form, being a projection onto a scattering plane of a more standard transverse momentum dependent factorization. Soft radiation is incorporated through a dijet soft function, which can be elegantly obtained to next-to-next-to-leading order (NNLO) due to the symmetries of the problem. We present numerical results for the TEEC resummed to next-to-next-to-leading logarithm (NNLL) matched to fixed order at the LHC. Our results constitute the first NNLL resummation for a dijet event shape observable at a hadron collider, and the first analytic result for a hadron collider dijet soft function at NNLO. We anticipate that the theoretical simplicity of the TEEC observable will make it indispensable for precision studies of QCD at the LHC, and as a playground for theoretical studies of factorization and its violation.

    hep-phnucl-thPRL(2019)·93 citations
30. 30*

    Thermal width of the Higgs boson in hot QCD matter

    Jacopo Ghiglieri🇨🇭 · Urs Achim Wiedemann🇨🇭

    Following Caron-Huot and combining results for the thermal dependence of spectral functions at large time-like momenta, we write an explicit expression for the thermal width of the Higgs boson to $\mathcal{O}({\alpha }_{\mathrm{s}})$ for $T\ll M_H$. It is an $\mathcal{O}({\alpha }_{\mathrm{s}}(T/M_H{)}^4)$ correction for $H\to gg$ and $H\to q\bar{q}$. We also compile corresponding results for the thermal width of the $Z$-boson, and we recall which generic structures of the field theory, accessible via the operator product expansion, fix the $T/M$-dependence of the decay of heavy particles.

    hep-phnucl-thPRD(2019)·12 citations
31. 31*

    New physics in $b\to s{e}^{+}{e}^{-}$?

    Jacky Kumar🇨🇦 · David London🇨🇦

    At present, the measurements of some observables in $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $B_s^0\to \varphi {\mu }^{+}{\mu }^{-}$ decays, and of $R_{K^{(\ast )}}\equiv \mathcal{B}(B\to K^{(\ast )}{\mu }^{+}{\mu }^{-})/\mathcal{B}(B\to K^{(\ast )}{e}^{+}{e}^{-})$, are in disagreement with the predictions of the standard model. While most of these discrepancies can be removed with the addition of new physics (NP) in $b\to s{\mu }^{+}{\mu }^{-}$, a difference of $>\sim 1.7\sigma$ still remains in the measurement of $R_{K^{\ast }}$ at small values of $q^2$, the dilepton invariant mass-squared. In the context of a global fit, this is not a problem. However, it does raise the question: if the true value of $R_{K^{\ast }}^{low}$ is near its measured value, what is required to explain it? In this paper, we show that, if one includes NP in $b\to s{e}^{+}{e}^{-}$, one can generate values for $R_{K^{\ast }}^{low}$ that are within $\sim 1\sigma$ of its measured value. Using a model-independent, effective-field-theory approach, we construct many different possible NP scenarios. We also examine specific models containing leptoquarks or a $Z^{\prime }$ gauge boson. Here, additional constraints from lepton-flavour-violating observables, $B_s^0$-${\bar{B}}_s^0$ mixing and neutrino trident production must be taken into account, but we still find a number of viable NP scenarios. For the various scenarios, we examine the predictions for $R_{K^{(\ast )}}$ in other $q^2$ bins, as well as for the observable $Q_5\equiv P_5^{\prime \mu \mu }-P_5^{\prime ee}$.

    hep-phhep-exPRD(2019)·36 citations
32. 32*

    Strong Evidence that the Galactic Bulge is Shining in Gamma Rays

    Oscar Macias🇯🇵 · Shunsaku Horiuchi🇺🇸 · Manoj Kaplinghat🇺🇸 · Chris Gordon🇳🇿 · Roland M. Crocker🇦🇺 · David M. Nataf🇺🇸

    There is growing evidence that the Galactic Center Excess identified in the $\text{Fermi}$-LAT gamma-ray data arises from a population of faint astrophysical sources. We provide compelling supporting evidence by showing that the morphology of the excess traces the stellar over-density of the Galactic bulge. By adopting a template of the bulge stars obtained from a triaxial 3D fit to the diffuse near-infrared emission, we show that it is detected at high significance. The significance deteriorates when either the position or the orientation of the template is artificially shifted, supporting the correlation of the gamma-ray data with the Galactic bulge. In deriving these results, we have used more sophisticated templates at low-latitudes for the $\text{Fermi}$ bubbles compared to previous work and the three-dimensional Inverse Compton (IC) maps recently released by the $\mathtt{GALPROP}$ team. Our results provide strong constraints on Millisecond Pulsar (MSP) formation scenarios proposed to explain the excess. We find that an $\text{admixture formation}$ scenario, in which some of the relevant binaries are $\text{primordial}$ and the rest are formed $\text{dynamically}$, is preferred over a primordial-only formation scenario at $7.6\sigma$ confidence level. Our detailed morphological analysis also disfavors models of the disrupted globular clusters scenario that predict a spherically symmetric distribution of MSPs in the Galactic bulge. For the first time, we report evidence of a high energy tail in the nuclear bulge spectrum that could be the result of IC emission from electrons and positrons injected by a population of MSPs and star formation activity from the same site.

    ↳ astro-ph.HEastro-ph.COastro-ph.GAhep-phJCAP(2019)·103 citations
33. 33*

    Pion Valence Quark Distribution from Matrix Element Calculated in Lattice QCD

    Raza Sabbir Sufian🇺🇸 · Joseph Karpie🇺🇸 · Colin Egerer🇺🇸 · Kostas Orginos🇺🇸 · Jian-Wei Qiu🇺🇸 · David G. Richards🇺🇸

    We present the first exploratory lattice QCD calculation of the pion valence quark distribution extracted from spatially separated current-current correlations in coordinate space. We show that an antisymmetric combination of vector and axial-vector currents provides direct information on the pion valence quark distribution. Using the collinear factorization approach, we calculate the perturbative tree-level kernel for this current combination and extract the pion valence distribution. The main goal of this article is to demonstrate the efficacy of this general lattice QCD approach in the reliable extraction of parton distributions. With controllable power corrections and a good understanding of the lattice systematics, this method has the potential to serve as a complementary to the many efforts to extract parton distributions in global analyses from experimentally measured cross sections. We perform our calculation on an ensemble of 2+1 flavor QCD using the isotropic-clover fermion action, with lattice dimensions $32^3\times 96$ at a lattice spacing \mbox{$a=0.127$ fm} and the quark mass equivalent to a pion mass $m_{\pi }\simeq 416$ MeV.

    ↳ hep-lathep-phnucl-thPRD(2019)·168 citations
34. 34*

    Roles of ${}^7$Be$(n,p{)}^7$Li resonances in big bang nucleosynthesis with time-dependent quark mass and Li reduction by a heavy quark mass

    Kanji Mori🇯🇵 · Motohiko Kusakabe🇨🇳

    Big bang nucleosynthesis (BBN) has been used as a probe of beyond-standard physics in the early Universe, which includes a time-dependent quark mass m_q. We investigate effects of a quark mass variation delta m_q on the cross sections of the 7Be(n, p)7Li reaction and primordial light element abundances taking into account roles of 8Be resonances in the reaction during BBN. This resonant reaction has not been investigated although behaviors of low-lying resonances are not trivial. It is found that a resonance at the resonance energy E_r=0.33 MeV enhances the reaction rate and lowers the 7Li abundance significantly when the quark mass variation is negative. Based upon up-to-date observational limits on primordial abundances of D, 4He and Li, the quark mass variation in the BBN epoch are derived. In a model in which the resonance energies of the reactions 3He(d, p)4He and 3H(d, n)4He are insensitive to the quark mass, we find that the Li abundance can be consistent with observations for delta m_q/m_q = (4--8) times 10^{-3}.

    ↳ astro-ph.COhep-phnucl-thPRD(2019)·15 citations
35. 35*

    Novel method for the direct measurement of the tau lepton dipole moments

    J. Fu🇮🇹 · M.A. Giorgi🇮🇹 · L. Henry🇪🇸 · D. Marangotto🇮🇹 · F. Martinez Vidal🇪🇸 · A. Merli🇮🇹 · N. Neri🇮🇹 · J. Ruiz Vidal🇪🇸

    A novel method for the direct measurement of the elusive magnetic and electric dipole moments of the tau lepton is presented. The experimental approach relies on the production of tau+ leptons from Ds+ -> tau+ nu_tau decays, originated in fixed-target collisions at the LHC. A sample of polarized tau+ leptons is kinematically selected and subsequently channeled in a bent crystal. The magnetic and electric dipole moments of the tau+ lepton are measured by determining the rotation of the spin-polarization vector induced by the intense electromagnetic field between crystal atomic planes. The experimental technique is discussed along with the expected sensitivities.

    ↳ hep-exhep-phPRL(2019)·45 citations
36. 36*

    Perspectives and Outlook from HEP Window on the Universe

    George Wei-Shu Hou🇹🇼

    This brief review grew out from the HEP Concluding Talk of the {\it 25th Anniversary of the Rencontres du Vietnam}, held August 2018 in Quy Nhon. The first two-thirds gives a Summary and Highlights, or snapshot, of High Energy Physics at the end of Large Hadron Collider (LHC) Run 2. It can be view as the combined effort of the program organizers, the invited plenary speakers, and finally filtered into the present mosaic. It certainly should not be viewed as comprehensive. In the second one-third, a more personal Perspective and Outlook is given, including my take on the flavor anomalies, and why the next 3 years, the period of Long Shutdown 2 plus first year (or more) of LHC Run~3, would be {\it Bright} and {\it Flavorful}, with much hope for uncovering {\it New Physics}. We advocate extra Yukawa couplings as {\it the most likely, next, New Physics} to be tested, the effect of which is already written in our Matter Universe.

    ↳ hep-exhep-phInt.J.Mod.Phys.A(2019)·7 citations
37. 37*

    MATHUSLA: A Detector Proposal to Explore the Lifetime Frontier at the HL-LHC

    Henry Lubatti · Cristiano Alpigiani · Juan Carlos Arteaga-Velázquez · Austin Ball · Liron Barak James Beacham · Yan Benhammo · Karen Salomé Caballero-Mora · Paolo Camarri · Tingting Cao · Roberto Cardarelli · John Paul Chou · David Curtin and 51 other authors

    The observation of long-lived particles at the LHC would reveal physics beyond the Standard Model, could account for the many open issues in our understanding of our universe, and conceivably point to a more complete theory of the fundamental interactions. Such long-lived particle signatures are fundamentally motivated and can appear in virtually every theoretical construct that address the Hierarchy Problem, Dark Matter, Neutrino Masses and the Baryon Asymmetry of the Universe. We describe in this document a large detector, MATHUSLA, located on the surface above an HL-LHC $pp$ interaction point, that could observe long-lived particles with lifetimes up to the Big Bang Nucleosynthesis limit of 0.1 s. We also note that its large detector area allows MATHUSLA to make important contributions to cosmic ray physics. Because of the potential for making a major breakthrough in our conceptual understanding of the universe, long-lived particle searches should have the highest level of priority.

    ↳ hep-exhep-phJINST(2020)·82 citations
38. 38*

    Classification and Recovery of Radio Signals from Cosmic Ray Induced Air Showers with Deep Learning

    M. Erdmann🇩🇪 · F. Schlueter🇩🇪 · R. Smida🇩🇪

    Radio emission from air showers enables measurements of cosmic particle kinematics and identity. The radio signals are detected in broadband Megahertz antennas among continuous background noise. We present two deep learning concepts and their performance when applied to simulated data. The first network classifies time traces as signal or background. We achieve a true positive rate of about 90% for signal-to-noise ratios larger than three with a false positive rate below 0.2%. The other network is used to clean the time trace from background and to recover the radio time trace originating from an air shower. Here we achieve a resolution in the energy contained in the trace of about 20% without a bias for $80\%$ of the traces with a signal. The obtained frequency spectrum is cleaned from signals of radio frequency interference and shows the expected shape.

    ↳ astro-ph.IMastro-ph.HEhep-phJINST(2019)·28 citations
39. 39*

    Highlights of discussions on Top quark and Higgs Physics in CKM2018

    Abideh Jafari🇨🇭

    In the 10^th International Workshop on the CKM Unitarity Triangle, the sessions of the High-p T flavor physics were devoted to the related topics in top quark physics, Higgs physics, semileptonic decays of B mesons and leptoquark searches. This notes summarizes the highlights of discussions on top quark and Higgs physics.

    ↳ hep-exhep-ph0 citations
40. 40*

    Introducing HIJING++: the Heavy Ion Monte Carlo Generator for the High-Luminosity LHC Era

    Gábor Bíró🇭🇺 · Gergely Gábor Barnaföldi🇭🇺 · Gábor Papp🇭🇺 · Miklos Gyulassy🇭🇺 · Péter Lévai🇭🇺 · Xin-Nian Wang🇨🇳 · Ben-Wei Zhang🇨🇳

    Beyond 2025 we will enter the High-Luminosity era of the LHC, right after the upgrades of the third Long Shutdown of the Large Hadron Collider (LHC). The ongoing state-of-the-art experimental instrument upgrades require high-performance simulation support in the background, that is modern, robust, and comes with long term support. The original FORTRAN based HIJING (Heavy Ion Jet INteraction Generator) has been used intensively since almost three decades by the high energy physics and heavy-ion community. However, it is getting overly challenging to conform to these new requirements. Our novel Monte Carlo event generator, the HIJING++ is the successor of the old FORTRAN version containing all the physics that its predecessor have. Moreover, among others a flexible module handling layer and an analysis interface is also introduced. This latter supports the most popular event container formats such as simple ascii, ROOT and the HepMC format, together with RIVET support. In this paper we compare the pre-release results of HIJING++ with proton-proton experimental data and Pythia8 calculations.

    ↳ physics.comp-phhep-phPoS(2019)·14 citations
41. 41*

    How to relax the cosmological neutrino mass bound

    Isabel M. Oldengott🇪🇸 · Gabriela Barenboim🇪🇸 · Sarah Kahlen🇩🇪 · Jordi Salvado🇪🇸 · Dominik J. Schwarz🇩🇪

    We study the impact of non-standard momentum distributions of cosmic neutrinos on the anisotropy spectrum of the cosmic microwave background and the matter power spectrum of the large scale structure. We show that the neutrino distribution has almost no unique observable imprint, as it is almost entirely degenerate with the effective number of neutrino flavours, $N_{\mathrm{eff}}$, and the neutrino mass, $m_{\nu }$. Performing a Markov chain Monte Carlo analysis with current cosmological data, we demonstrate that the neutrino mass bound heavily depends on the assumed momentum distribution of relic neutrinos. The message of this work is simple and has to our knowledge not been pointed out clearly before: Cosmology allows that neutrinos have larger masses if their average momentum is larger than that of a perfectly thermal distribution. Here we provide an example in which the mass limits are relaxed by a factor of two.

    ↳ astro-ph.COhep-phJCAP(2019)·52 citations
42. 42*

    Distribution of solutions of the fastest apparent convergence condition in optimized perturbation theory and its relation to anti-Stokes lines

    Shoichiro Tsutsui🇯🇵 · Takahiro M. Doi🇯🇵

    We discuss fundamental properties of the fastest apparent convergence (FAC) condition which is used as a variational criterion in optimized perturbation theory (OPT). We examine an integral representation of the FAC condition and a distribution of the zeros of the integral in a complex artificial parameter space on the basis of theory of Lefschetz thimbles. We find that the zeros accumulate on a certain line segment so-called anti-Stokes line in the limit $K\to \infty$, where $K$ is a truncation order of a perturbation series. This phenomenon gives an underlying mechanism that physical quantities calculated by OPT can be insensitive to the choice of the artificial parameter.

    ↳ hep-thhep-phmath-phmath.MPAnnals Phys.(2019)·2 citations
43. 43*

    Tides in merging neutron stars: Consistency of the GW170817 event with experimental data on finite nuclei

    Tuhin Malik🇮🇳 · B. K. Agrawal🇮🇳 · J.N. De🇮🇳 · S.K. Samaddar🇮🇳 · C. Providência🇵🇹 · C. Mondal🇪🇸 · T.K. Jha🇮🇳

    The agreement of the nuclear equation of state (EoS) deduced from the GW170817 based tidal deformability with the one obtained from empirical data on microscopic nuclei is examined. It is found that suitably chosen experimental data on isoscalar and isovector modes of nuclear excitations together with the observed maximum neutron star mass constrain the EoS which displays a very good congruence with the GW170817 inspired one. The giant resonances in nuclei are found to be instrumental in limiting the tidal deformability parameter and the radius of neutron star in somewhat narrower bounds. At the 1$\sigma$ level, the values of the canonical tidal deformability ${\Lambda }_{1.4}$ and the neutron star radius $R_{1.4}$ come out to be $267\pm 144$ and $11.6\pm 1.0$ km, respectively.

    ↳ nucl-thgr-qchep-phPRC(2019)·40 citations
44. 44*

    Multi-particle and charge-dependent azimuthal correlations in heavy-ion collisions at the Relativistic Heavy-Ion Collider

    Bjoern Schenke🇺🇸 · Chun Shen🇺🇸 · Prithwish Tribedy🇺🇸

    We study multi-particle azimuthal correlations in relativistic heavy-ion collisions at a center of mass energy of 200 GeV. We use the IP-Glasma model to initialize the viscous hydrodynamic simulation MUSIC and employ the UrQMD transport model for the low temperature region of the collisions. In addition, we study effects of local charge and global momentum conservation among the sampled particles. With the exception of the lowest order three particle correlator $C_{112}$, our framework provides a good description of the existing charge inclusive azimuthal correlation data for Au+Au and U+U collisions at RHIC. We also present results for charge dependent two and three particle correlators in Au+Au and U+U collisions, and make predictions for isobar (Ru+Ru & Zr+Zr) collisions to provide a much needed baseline for the search for the Chiral Magnetic Effect at RHIC.

    ↳ nucl-thhep-phnucl-exPRC(2019)·78 citations
45. 45*

    Scattering Amplitudes and the Conservative Hamiltonian for Binary Systems at Third Post-Minkowskian Order

    Zvi Bern🇺🇸 · Clifford Cheung🇺🇸 · Radu Roiban🇺🇸 · Chia-Hsien Shen🇺🇸 · Mikhail P. Solon🇺🇸 · Mao Zeng🇨🇭

    We present the amplitude for classical scattering of gravitationally interacting massive scalars at third post-Minkowskian order. Our approach harnesses powerful tools from the modern amplitudes program such as generalized unitarity and the double-copy construction, which relates gravity integrands to simpler gauge-theory expressions. Adapting methods for integration and matching from effective field theory, we extract the conservative Hamiltonian for compact spinless binaries at third post-Minkowskian order. The resulting Hamiltonian is in complete agreement with corresponding terms in state-of-the-art expressions at fourth post-Newtonian order as well as the probe limit at all orders in velocity. We also derive the scattering angle at third post-Minkowskian order.

    ↳ hep-thgr-qchep-phPRL(2019)·628 citations
46. 46*

    Towards machine learning in the classification of Z2xZ2 orbifold compactifications

    Alon E. Faraggi🇬🇧 · Glyn Harries🇬🇧 · Benjamin Percival🇬🇧 · John Rizos🇬🇷

    Systematic classification of Z2xZ2 orbifold compactifications of the heterotic-string was pursued by using its free fermion formulation. The method entails random generation of string vacua and analysis of their entire spectra, and led to discovery of spinor-vector duality and three generation exophobic string vacua. The classification was performed for string vacua with unbroken SO(10) GUT symmetry, and progressively extended to models in which the SO(10) symmetry is broken to the SO(6)xSO(4), SU(5)xU(1), SU(3)xSU(2)xU(1)^2 and SU(3)xU(1)xSU(2)^2 subgroups. Obtaining sizeable number of phenomenologically viable vacua in the last two cases requires identification of fertility conditions. Adaptation of machine learning tools to identify the fertility conditions will be useful when the frequency of viable models becomes exceedingly small in the total space of vacua.

    ↳ hep-thhep-phJ.Phys.Conf.Ser.(2020)·7 citations
47. 47*

    Physics Beyond Colliders: QCD Working Group Report

    A. Dainese🇮🇹 · M. Diehl🇩🇪 · P. Di Nezza🇮🇹 · J. Friedrich🇩🇪 · M. Gaździcki🇩🇪 · G. Graziani🇮🇹 · C. Hadjidakis🇫🇷 · J. Jäckel🇩🇪 · J. P. Lansberg🇫🇷 · A. Magnon🇨🇭 · G. Mallot🇨🇭 · F. Martinez Vidal🇪🇸 and 11 other authors

    This report summarises the main findings of the QCD Working Group in the CERN Physics Beyond Colliders Study.

    ↳ hep-exhep-phnucl-exnucl-th26 citations
48. 48*

    Pulsar Timing Probes of Primordial Black Holes and Subhalos

    Jeff A. Dror🇺🇸 · Harikrishnan Ramani🇺🇸 · Tanner Trickle🇺🇸 · Kathryn M. Zurek🇺🇸

    Pulsars act as accurate clocks, sensitive to gravitational redshift and acceleration induced by transiting clumps of matter. We study the sensitivity of pulsar timing arrays (PTAs) to single transiting compact objects, focusing on primordial black holes and compact subhalos in the mass range from $10^{-12}{M}_{\odot }$ to well above $100M_{\odot }$. We find that the Square Kilometer Array can constrain such objects to be a subdominant component of the dark matter over this entire mass range, with sensitivity to a dark matter sub-component reaching the sub-percent level over significant parts of this range. We also find that PTAs offer an opportunity to probe substantially less dense objects than lensing because of the large effective radius over which such objects can be observed, and we quantify the subhalo concentration parameters which can be constrained.

    ↳ astro-ph.COastro-ph.HEhep-phPRD(2019)·140 citations
49. 49*

    A brief remark on convexity of effective potentials and de Sitter Swampland conjectures

    Archil Kobakhidze🇦🇺

    Recently proposed de Sitter Swampland conjectures imply non-trivial constraints on a scalar field potential in any effective field theory that admits a quantum gravity completion. The original conjecture apparently excludes many phenomenologically motivated scalar potentials with de Sitter extrema, such as the perturbative Standard Model Higgs potential and the QCD axion potential, as the viable low-energy theories. Subsequently, the refined, weaker conjecture was proposed. However, the full effective potential, having been defined as a Legendre transform, is necessarily convex. This ensures that the original Swampland conjecture can actually be satisfied in phenomenologically relevant models, providing no de Sitter vacua exist.

    ↳ physics.gen-phhep-phhep-th9 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.