Tue·Jun 29, 2021Tuesday·June 29, 2021

1. 01*

   Resonance refraction and neutrino oscillations

   Alexei Y. Smirnov🇩🇪 · Victor B. Valera🇩🇰

   The refraction index and matter potential depend on neutrino energy and this dependence has a resonance character associated to the production of the mediator in the $s-$channel. For light mediators and light particles of medium (background) the resonance can be realized at energies accessible to laboratory experiments. We study properties of the energy dependence of the potential for different C-asymmetries of background. Interplay of the background potential and the vacuum term leads to (i) bump in the oscillation probability in the resonance region, (ii) dip related to the MSW resonance in the background, (iii) substantial deviation of the effective $\Delta m^2$ above the resonance from the low energy value, etc. We considered generation of mixing in the background. Interactions with background shifts the energy of usual MSW resonance and produces new MSW resonances. Searches of the background effects allow us to put bounds on new interactions of neutrinos and properties of the background. We show that explanation of the MiniBooNE excess, as the bump due to resonance refraction, is excluded.

   hep-phhep-exJHEP(2021)·29 citations
2. 02*

   Unbinned Angular Analysis of $B\to D^{\ast }\ell {\nu }_{\ell }$ and the Right-handed Current

   Zhuo-Ran Huang🇫🇷 · Emi Kou🇫🇷 · Cai-Dian Lü🇨🇳 · Ru-Ying Tang🇨🇳

   In this article, we perform a sensitivity study of an unbinned angular analysis of the $B\to D^{\ast }\ell {\nu }_{\ell }$ decay, including the contributions from the right-handed current. We show that the angular observable can constrain very strongly the right-handed current without the intervention of the yet unsolved $V_{cb}$ puzzle.

   hep-phhep-exPRD(2022)·14 citations
3. 03*

   Majorana Dark Matter and Neutrino mass in a singlet-doublet extension of the Standard Model

   Manoranjan Dutta (1)🇮🇳 · Subhaditya Bhattacharya (2)🇮🇳 · Purusottam Ghosh (3)🇮🇳 · Narendra Sahu (1) ((1) Indian Institute of Technology Hyderabad, (2) Indian Institute of Technology Guwahati (3) Harish-Chandra Research Institute, Allahabad)🇮🇳

   A minimal extension of the Standard Model (SM) by a vector-like fermion doublet and three right handed (RH) singlet neutrinos is proposed in order to explain dark matter and tiny neutrino mass simultaneously. The DM arises as a mixture of the neutral component of the fermion doublet and one of the RH neutrinos, both assumed to be odd under an imposed ${\mathcal{Z}}_2$ symmetry. Being Majorana in nature, the DM escapes from $Z$-mediated direct search constraints to mark a significant difference from singlet-doublet Dirac DM. The other two ${\mathcal{Z}}_2$ even heavy RH neutrinos give rise masses and mixing of light neutrinos via Type-I Seesaw mechanism. Relic density and direct search allowed parameter space for the model is investigated through detailed numerical scan.

   hep-phSpringer Proc.Phys.(2022)·7 citations
4. 04*

   Off-shell chromomagnetic dipole moments in the SM at and beyond the $Z$ gauge boson mass scale

   J. Montano-Dominguez🇲🇽 · B. Quezadas-Vivian🇲🇽 · F. Ramirez-Zavaleta🇲🇽 · E. S. Tututi🇲🇽 · E. Urquiza-Trejo🇲🇽

   The off-shell anomalous chromomagnetic dipole moment of the standard model quarks ($u$, $d$, $s$, $c$ and $b$), at the $Z$ gauge boson mass scale, is computed by using the $\overline{\text{MS}}$ scheme. The numerical results disagree with all the previous predictions reported in the literature and show a discrepancy of up to two orders of magnitude in certain situations.

   hep-phInt.J.Mod.Phys.A(2023)·4 citations
5. 05*

   Probing gluon number density with electron-dijet correlations at EIC

   Andreas van Hameren🇵🇱 · Piotr Kotko🇵🇱 · Krzysztof Kutak🇵🇱 · Sebastian Sapeta🇵🇱 · Elżbieta Żarów🇵🇱

   We propose a novel way of studying the gluon number density (the so-called Weizsäcker-Williams gluon distribution) using the planned Electron Ion Collider. Namely, with the help of the azimuthal correlations between the total transverse momentum of the dijet system and the scattered electron, we examine an interplay between the effect of the soft gluon emissions (the Sudakov form factor) and the gluon saturation effects. The kinematic cuts are chosen such that the dijet system is produced in the forward direction in the laboratory frame, which provides an upper bound on the probed longitudinal fractions of the hadron momentum carried by scattered gluons. Further cuts enable us to use the factorization formalism that directly involves the unpolarized Weizsäcker-Williams gluon distribution. We find this observable to be very sensitive to the soft gluon emission and moderately sensitive to the gluon saturation.

   hep-phhep-exEPJC(2021)·24 citations
6. 06*

   Fermionic decays of NMSSM Higgs bosons under LHC 13 TeV constraints

   Marwa Telba🇸🇦 · Maien Binjonaid🇸🇦

   This paper investigates the impact of the recent LHC constraints on the Higgs sector in the semi-constrained version of the Next-to-Minimal Supersymmetric Standard Model. Our analysis focuses on the parameter space for which the value of the Higgs doublet-singlet coupling, $\lambda$, is large as possible, while the ratio between the vacuum expectation values of the two Higgs doublets, $\tan \beta$, is small as possible. Under the current constraints, we present the possible fermionic decay channels and reduced cross-section into fermions final states for the lightest neutral Higgs bosons in the NMSSM, $(h_1$, $h_2$, and $a_1)$. We found that the branching ratios of the non SM-like Higgs ($a_1$ and $h_2$) into a pair of bottom quarks are near 90\% level when the Higgs mass below 400 GeV. Moreover, the branching ratio of $h_2/a_1\to t\bar{t}$ can reach unity for all mass ranges when these bosons are mostly singlet.

   hep-phResults Phys.(2021)·1 citation
7. 07*

   A step towards a consistent treatment of chiral theories at higher loop order: the abelian case

   Adriano Cherchiglia🇧🇷

   As recently pointed out, regularization schemes defined in four-dimensions may also face inconsistencies in the presence of chiral fermions. In this work, we extend this analysis to two-loop order. Adopting the implicit regularization as working arena, we discuss in detail how a consistent version of the method can be envisaged, and present many of the subtleties that appear at two-loop order using an abelian chiral model as working example.

   hep-phNPB(2023)·12 citations
8. 08*

   Anomalous couplings in Higgs-boson pair production at approximate NNLO QCD

   Daniel de Florian🇦🇷 · Ignacio Fabre🇨🇭 · Gudrun Heinrich🇩🇪 · Javier Mazzitelli🇩🇪 · Ludovic Scyboz🇬🇧

   We combine NLO predictions with full top-quark mass dependence with approximate NNLO predictions for Higgs-boson pair production in gluon fusion, including the possibility to vary coupling parameters within a non-linear Effective Field Theory framework containing five anomalous couplings for this process. We study the impact of the anomalous couplings on various observables, and present Higgs-pair invariant-mass distributions at seven benchmark points characterising different $m_{hh}$ shape types. We also provide numerical coefficients for the approximate NNLO cross section as a function of the anomalous couplings at $\sqrt{s}=14$ TeV.

   hep-phJHEP(2021)·24 citations
9. 09*

   Hidden-bottom hadronic decays of ${\rm Y}(10753)$ with a ${\eta }^{(\prime )}$ or $\omega$ emission

   Yu-Shuai Li🇨🇳 · Zi-Yue Bai🇨🇳 · Qi Huang🇨🇳 · Xiang Liu🇨🇳

   In this work, we propose the $4S$-$3D$ mixing scheme to assign the ${\rm Y}(10753)$ into the conventional bottomonium family. Under this interpretation, we further study its hidden-bottom hadronic decays with a ${\eta }^{(\prime )}$ or $\omega$ emission, which include ${\rm Y}(10753)\to {\rm Y}(1S){\eta }^{(\prime )}$, ${\rm Y}(10753)\to h_b(1P)\eta$ and ${\rm Y}(10753)\to {\chi }_{bJ}\omega$ ($J$=0,1,2) processes. Since the ${\rm Y}(10753)$ is above the $B\bar{B}$ threshold, the coupled-channel effect cannot be ignored, thus, when calculating partial decay widths of these ${\rm Y}(10753)$ hidden-bottom decays, we apply the hadronic loop mechanism. Our result shows that these discussed decay processes own considerable branching fractions with the order of magnitude of $10^{-4}\sim 10^{-3}$, which can be accessible at Belle II and other future experiments.

   hep-phhep-exPRD(2021)·40 citations
10. 10*

    Scalar dark matter and Muon $g-2$ in a $U(1{)}_{L_{\mu }-L_{\tau }}$ model

    XinXin Qi🇨🇳 · AiGeng Yang🇨🇳 · Wei Liu🇨🇳 · Hao Sun🇨🇳

    We consider a simple scalar dark matter model within the frame of gauged $L_{\mu }-L_{\tau }$ symmetry. A gauge boson $Z^{\prime }$ as well as two scalar fields $S$ and $\Phi$ are introduced to the Standard Model (SM). $S$ and $\Phi$ are SM singlet but both with $U(1{)}_{L_{\mu }-L_{\tau }}$ charge. The real component and imaginary component of $S$ can acquire different masses after spontaneously symmetry breaking, and the lighter one can play the role of dark matter which is stabilized by the residual $Z_2$ symmetry. A viable parameter space is considered to discuss the possibility of light dark matter as well as co-annihilation case, and we present current $(g-2{)}_{\mu }$ anomaly, Higgs invisible decay, dark matter relic density as well as direct detection constriants on the parameter space.

    hep-phCPC(2022)·14 citations
11. 11*

    "Smashing more than two": Deuteron production in relativistic heavy ion collisions via stochastic multi-particle reactions

    Jan Staudenmaier🇩🇪 · Dmytro Oliinychenko🇺🇸 · Juan M. Torres-Rincon🇩🇪 · Hannah Elfner🇩🇪

    We study the deuteron production via the deuteron pion and nucleon catalysis reactions, $\pi pn\leftrightarrow \pi d$ and $Npn\leftrightarrow Nd$, by employing stochastic multi-particle reactions in the hadronic transport approach SMASH for the first time. This is an improvement compared to previous studies, which introduced an artificial fake resonance $d^{\prime }$ to simulate these $3\leftrightarrow 2$ reactions as a chain of $2\leftrightarrow 2$ reactions. The derivation of the stochastic criterion for multi-particle reactions is presented in a comprehensive fashion and its implementation is tested against an analytic expression for the scattering rate and the equilibrating particle yields in box calculations. We then study Au + Au collisions at $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV, where we find that multi-particle collisions substantially reduce the time required for deuterons to reach partial chemical equilibrium with nucleons. Subsequently, the final yield of $d$ is practically independent from the number of $d$ at particlization, confirming the results of previous studies. The mean transverse momentum and the integrated elliptic flow as a function of centrality are rather insensitive to the exact realization of the $2\leftrightarrow 3$ reactions.

    hep-phnucl-thPRC(2021)·67 citations
12. 12*

    Hadron gas in the presence of a magnetic field using non-extensive statistics: A transition from diamagnetic to paramagnetic system

    Girija Sankar Pradhan🇮🇳 · Dushmanta Sahu🇮🇳 · Suman Deb🇮🇳 · Raghunath Sahoo🇮🇳

    Non-central heavy-ion collisions at ultra-relativistic energies are unique in producing magnetic fields of the largest strength in the laboratory. Such fields being produced at the early stages of the collision could affect the properties of Quantum Chromodynamics (QCD) matter formed in the relativistic heavy-ion collisions. The transient magnetic field leaves its reminiscence, which in principle, can affect the thermodynamic and transport properties of the final state dynamics of the system. In this work, we study the thermodynamic properties of a hadron gas in the presence of an external static magnetic field using a thermodynamically consistent non-extensive Tsallis distribution function. Various thermodynamical observables such as energy density ($ϵ$), entropy density ($s$), pressure ($P$) and speed of sound ($c_{\mathrm{s}}$) are studied. Investigation of magnetization ($M$) is also performed and this analysis reveals an interplay of diamagnetic and paramagnetic nature of the system in the presence of a magnetic field of varying strength. Further, to understand the system dynamics under equilibrium and non-equilibrium conditions, the effect of the non-extensive parameter ($q$) on the above observables is also studied.

    hep-phnucl-thJ.Phys.G(2023)·14 citations
13. 13*

    Rise and fall of $\Lambda$ and $\bar{\Lambda }$ global polarization in semi-central heavy-ion collisions at HADES, NICA and RHIC energies from the core-corona model

    Alejandro Ayala🇲🇽 · Isabel Domínguez🇲🇽 · Ivonne Maldonado🇲🇽 · María Elena Tejeda-Yeomans🇲🇽

    We compute the $\Lambda$ and $\overline{\Lambda }$ global polarizations in semi-central heavy-ion collisions using the core-corona model where the source of $\Lambda$'s and $\overline{\Lambda }$'s is taken as consisting of a high-density core and a less dense corona. We show that the overall properties of the polarization excitation functions can be linked to the relative abundance of $\Lambda$s coming from the core versus those coming from the corona. For low collision energies, the former are more abundant whereas for higher energies the latter become more abundant. The main consequence of this reversing of the relative abundance is that both polarizations peak at collision energies $\sqrt{s_{NN}}\lesssim 10$ GeV. The exact positions and heights of these peaks depend not only on this reversal of relative abundances, but also on the centrality class, which is directly related to the QGP volume and lifetime, as well as on the relative abundances of $\Lambda$s and $\overline{\Lambda }$s in the core and corona regions.The intrinsic polarizations are computed from a field theoretical approach that links the alignment of the strange quark spin with the thermal vorticity and modeling the QGP volume and lifetime using a Bjorken expansion scenario. We predict that the $\Lambda$ and $\overline{\Lambda }$ global polarizations should peak at the energy range accessible to NICA and HADES.

    hep-phnucl-exnucl-thPRC(2022)·29 citations
14. 14*

    NNLO soft function for threshold single inclusive jet production

    Yaroslav Balytskyi🇺🇸 · Jianbo Gao🇨🇳

    We present a computation of the global soft function for single-inclusive hadronic jet production at next-to-next-to-leading order (NNLO) in the strong coupling constant involving four light-like Wilson lines. Our soft function belongs to SCET${}_{\text{I}}$ observables obeying the non-Abelian exponentiation theorem. We provide the calculation of the soft function involving four collinear light-cone directions for all $2\to 2$ processes extending the previous result. We perform the threshold resummation for these processes at the next-to-next-to-leading logarithmic accuracy and present the corresponding numerical results.

    hep-phPRD(2021)·0 citations
15. 15*

    Analytical Approach of Matter Effect on (3+1) Neutrino Oscillation

    Vivek Kumar Nautiyal🇮🇳 · Bipin Singh Koranga🇮🇳

    Abstract We study the analytic expression for four flavor neutrino oscillation in the presence of matter. We calculate the time evolution operator on flavor and mass basis. We find the matter dependent mass square difference and neutrino transition probabilities for (3+1) four flavor neutrino oscillation.

    hep-ph2 citations
16. 16*

    TeV Scale Resonant Leptogenesis with $L_{\mu }-L_{\tau }$ Gauge Symmetry in the Light of Muon $(g-2)$

    Debasish Borah🇮🇳 · Arnab Dasgupta🇰🇷 · Devabrat Mahanta🇮🇳

    Motivated by the growing evidence for the possible lepton flavour universality violation after the first results from Fermilab's muon $(g-2)$ measurement, we revisit one of the most widely studied anomaly free extensions of the standard model namely, gauged $L_{\mu }-L_{\tau }$ model, to find a common explanation for muon $(g-2)$ as well as baryon asymmetry of the universe via leptogenesis. The minimal setup allows TeV scale resonant leptogenesis satisfying light neutrino data while the existence of light $L_{\mu }-L_{\tau }$ gauge boson affects the scale of leptogenesis as the right handed neutrinos are charged under it. For $L_{\mu }-L_{\tau }$ gauge boson mass at GeV scale or above, the muon $(g-2)$ favoured parameter space is already ruled out by other experimental data while bringing down its mass to sub-GeV regime leads to vanishing lepton asymmetry due to highly restrictive structures of lepton mass matrices at the scale of leptogenesis. Extending the minimal model with two additional Higgs doublets can lead to a scenario consistent with successful resonant leptogenesis and muon $(g-2)$ while satisfying all relevant experimental data.

    hep-phastro-ph.COPRD(2021)·38 citations
17. 17*

    Angularity in DIS at next-to-next-to-leading log accuracy

    Jiawei Zhu🇨🇳 · Daekyoung Kang🇨🇳 · Tanmay Maji🇨🇳

    Angularity is a class of event-shape observables that can be measured in deep-inelastic scattering. With its continuous parameter $a$ one can interpolate angularity between thrust and broadening and further access beyond the region. Providing such systematic way to access various observables makes angularity attractive in analysis with event shapes. We give the definition of angularity for DIS and factorize the cross-section by using soft-collinear effective theory. The factorization is valid in a wide range of $a$ below and above thrust region but invalid in broadening limit. It contains an angularity beam function, which is new result and we give the expression at $\mathcal{O}(\text{as})$. We also perform large log resummation of angularity and make predictions at various values of $a$ at next-to-next-to-leading log accuracy.

    hep-phnucl-thJHEP(2021)·16 citations
18. 18*

    General one-loop contributions to the decay $H\to {\nu }_l{\bar{\nu }}_l\gamma$

    Khiem Hong Phan🇻🇳 · Dzung Tri Tran🇻🇳 · Le Tho Hue🇻🇳

    General one-loop contributions to the decay amplitudes $H\to {\nu }_l{\bar{\nu }}_l\gamma$ are presented, considering all possible contributions of additional heavy vector gauge bosons, fermions, and charged (and also neutral) scalar particles appearing in the loop diagrams. Moreover, the results can be applied directly when extra neutrinos (apart from three ones in standard model) are taken into account in final states. Analytic results are presented in terms of Passarino-Veltman scalar functions which can be evaluated numerically using {\tt LoopTools}. In the standard model framework, these analytical results are generated and cross-checked with previous computations. We find that our results are well consistent with these computations. Within standard model limit, phenomenological results for the decay channels are also studied using the updated input parameters at the Large Hadron Collider.

    hep-phPTEP(2021)·14 citations
19. 19*

    Deciphering the light vector meson contribution to the cross sections of $e^{+}{e}^{-}$ annihilations into the open-strange channels through a combined analysis

    Jun-Zhang Wang🇨🇳 · Li-Ming Wang🇨🇳 · Xiang Liu🇨🇳 · Takayuki Matsuki🇯🇵

    In this work, we perform a combined analysis to the measured data of the cross section of open-strange processes $e^{+}{e}^{-}\to K^{+}{K}^{-}$, $e^{+}{e}^{-}\to K{\bar{K}}^{\ast }+c.c.$, $e^{+}{e}^{-}\to K^{\ast +}{K}^{\ast -}$, $e^{+}{e}^{-}\to K_1(1270{)}^{+}{K}^{-}$, $e^{+}{e}^{-}\to K_1(1400{)}^{+}{K}^{-}$, $e^{+}{e}^{-}\to K_2^{\ast }(1430)\bar{K}+c.c.$ and $e^{+}{e}^{-}\to K(1460{)}^{+}{K}^{-}$ with the support of study of hadron spectroscopy. We reveal the contribution of the possible light vector mesons around 2 GeV to reproduce the cross section data of the reported open-strange processes from $e^{+}{e}^{-}$ annihilation which may provide a new perspective to construct the light vector meson family and understand the $Y(2175)$.

    hep-phhep-exPRD(2021)·17 citations
20. 20*

    ${\bar{\nu }}_{\mu }$ induced quasielastic production of hyperons leading to pions

    A. Fatima🇮🇳 · M. Sajjad Athar🇮🇳 · S. K. Singh🇮🇳

    The quasielastic production cross sections and polarizations of the hyperons induced by ${\bar{\nu }}_{\mu }$ on the free nucleon as well as from ${}^{40}$Ar in the sub-GeV energy region has been reviewed [1-5]. The effects of the second class currents in the axial vector sector with and without T-invariance as well as the effect of SU(3) symmetry breaking are also studied. We find that the cross sections and the various polarization components can effectively be used to determine the axial vector transition form factors in the strangeness sector and to test the validity of various symmetries of the weak hadronic currents like G-invariance, T-invariance and SU(3) symmetry. These hyperons decay dominantly into pions giving an additional contribution to the weak pion production induced by the antineutrinos. In the case of nuclear targets like ${}^{40}$Ar, this contribution is shown to be significant when compared with the pion production by the $\Delta$ excitations in the energy range of $E_{{\bar{\nu }}_{\mu }}\le 0.7$ GeV [1]. This study could be useful for the DUNE experiment where argon will be used as the target material and the electronic imaging of particles is possible and the particle tracks can be identified.

    hep-phhep-exEur.Phys.J.ST(2021)·11 citations
21. 21*

    Deep inelastic (anti)neutrino-nucleus scattering

    V. Ansari🇮🇳 · M. Sajjad Athar🇮🇳 · H. Haider🇮🇳 · I. Ruiz Simo🇪🇸 · S. K. Singh🇮🇳 · F. Zaidi🇮🇳

    The present status of the field theoretical model studies of the deep inelastic scattering induced by (anti)neutrino on the nuclear targets in a wide range of Bjorken variable $x$ and four momentum transfer square $Q^2$, has been reviewed~\cite{Haider:2011qs,Haider:2012nf,Haider:2016zrk,Zaidi:2019mfd,Zaidi:2019asc,Ansari:2020xne}. The effect of the nonperturbative corrections such as target mass correction and higher twist effects, perturbative evolution of the parton densities, nuclear medium modifications in the nucleon structure functions, nuclear isoscalarity corrections on the weak nuclear structure functions have been discussed. These structure functions have been used to obtain the differential scattering cross sections. The various nuclear medium effects like the Fermi motion, binding energy, nucleon correlations, mesonic contributions, shadowing and antishadowing corrections relevant in the different regions of $x$ and $Q^2$ have been discussed. The numerical results for the structure functions and the cross sections are compared with some of the available experimental data including the recent results from MINERvA. The predictions are made in argon nuclear target which is planned to be used as a target material in DUNE at the Fermilab.

    hep-phEur.Phys.J.ST(2021)·12 citations
22. 22*

    Divergences in anomalous dimension matrices of quarks at three loops: Explanation and simple solution

    Adrian Lewandowski (Department of Theoretical Physics, Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology)🇵🇱

    Three-loop counterterms for the Standard Model (SM) revealed that the matrix of anomalous dimensions ($\gamma$) of quarks is divergent in the $d\to 4$ limit unless a carefully chosen non-Hermitian square-root of $Z$ matrix is used in the textbook formula for $\gamma$. Here, an alternative prescription is given, which expresses $\gamma$ and $\beta$ functions directly in terms of counterterms (instead of $\sqrt{Z}$ and conventional `bare couplings') and produces finite results. In the SM, this prescription $automatically$ reproduces results obtained previously by adjusting $\sqrt{Z}$.

    hep-phhep-thPRD(2021)·0 citations
23. 23*

    String breaking in a cold wind as seen by string models

    Oleg Andreev🇷🇺

    Using the gauge/string duality, we model a heavy quark-antiquark pair in a color singlet state moving through a cold medium and explore the consequences of temperature and velocity on string breaking. We show that the string breaking distance slowly varies with temperature and velocity away from the critical line but could fall near it.

    hep-phhep-lathep-thnucl-thNPB(2022)·3 citations
24. 24*

    Non-Leptonic Decays of Bileptons

    Gennaro Corcella🇮🇹 · Claudio Coriano🇮🇹 · Antonio Costantini🇧🇪 · Paul H. Frampton🇮🇹

    We provide a detailed analysis of the decays of doubly-charged bilepton gauge bosons $Y^{\pm \pm }$, as predicted in models based on a $SU(3{)}_C\times SU(3{)}_L\times U(1{)}_X$ symmetry. In addition to the decay modes into same-sign lepton pairs, which were already investigated in scenarios wherein each branching ratio was about one third, there are, depending on the mass spectrum, possible non-leptonic decays which reduce the leptonic rates. These non-leptonic decays are typically into a light quark (antiquark) and a heavy TeV-scale antiquark (quark), which carries double lepton number and decays via virtual bileptons. We choose two benchmark points to represent the particle spectrum and present a phenomenological analysis of such decays. We find that, while the LHC statistics are too low, even in the high-luminosity phase, they can lead to a visible signal at a future 100 TeV hadron collider (FCC-$hh$). A more exhaustive exploration with a rigorous inclusion of tagging efficiencies, detector simulations and higher-order corrections to the partonic cross section, aiming at assessing the reach of LHC and FCC-$hh$ for bileptons as a function of the model parameters, as well as a recast of four-top searches in terms of the bilepton model, are deferred to future work.

    hep-phPLB(2022)·6 citations
25. 25*

    New physics in double Higgs production at NLO

    Bo-Yan Huang🇺🇸

    After observing the Higgs boson by the ATLAS and CMS experiments at the LHC, accurate measurements of its properties, which allow us to study the electroweak symmetry breaking mechanism, become a high priority for particle physics. The most promising of extracting the Higgs self-coupling at hadron colliders is by examining the double Higgs production, especially in the $b\bar{b}\gamma \gamma$ channel. In this work, we presented full loop calculation for both SM and New Physics effects of the Higgs pair production to next-to-leading-order (NLO), including loop-induced processes $gg\to HH$, $gg\to HHg$, and $qg\to qHH$. We also included the calculation of the corrections from diagrams with only one QCD coupling in $qg\to qHH$, which was neglected in the previous studies. With the latest observed limit on the HH production cross-section, we studied the constraints on the effective Higgs couplings for the LHC at center-of-mass energies of 14 TeV and a provisional 100 TeV proton collider within the Future-Circular-Collider (FCC) project. To obtain results better than using total cross-section alone, we focused on the $b\bar{b}\gamma \gamma$ channel and divided the differential cross-section into low and high bins based on the total invariant mass and $p_T$ spectra. The new physics effects are further constrained by including extra kinematic information. However, some degeneracy persists, as shown in previous studies, especially in determining the Higgs trilinear coupling. Our analysis shows that the degeneracy is reduced by including the full NLO corrections.

    hep-ph0 citations
26. 26*

    Toward a magnetic warm inflation scenario

    Gabriella Piccinelli🇲🇽 · Angel Sánchez🇲🇽

    In this work we explore the effects that a possible primordial magnetic field can have on the inflaton effective potential, taking as the underlying model a warm inflation scenario, based on global supersymmetry with a new-inflation-type potential. The decay scheme for the inflaton field is a two-step process of radiation production, where the inflaton couples to heavy intermediate superfields, which in turn interact with light particles. In this context, we consider that both sectors, heavy and light, are charged and work in the strong magnetic field approximation for the light fields. We find an analytical expression for the one-loop effective potential, for an arbitrary magnetic field strength, and show that the trend of the magnetic contribution is to make the potential flatter in the origin's vicinity, preserving the conditions for a successful inflationary process. This result is backed up by the behavior of slow-roll parameter $ϵ$. The viability of this magnetic warm inflation scenario is also supported by the estimation of the effect of the magnetic field on the heavy particles decay width.

    hep-phastro-ph.COPRD(2022)·5 citations
27. 27*

    Production of heavy charged particles in proton-proton ultraperipheral collisions at the Large Hadron Collider: survival factor

    S. I. Godunov🇷🇺 · V. A. Novikov🇷🇺 · A. N. Rozanov🇷🇺 · M. I. Vysotsky🇷🇺 · E. V. Zhemchugov🇷🇺

    Ultraperipheral collisions of high energy protons are a source of approximately real photons colliding with each other. Photon fusion can result in production of yet unknown charged particles in very clean events. The cleanliness of such an event is due to the requirement that the protons survive during the collision. Finite sizes of the protons reduce the probability of such outcome compared to point-like particles. We calculate the survival factors and cross sections for the production of heavy charged particles at the Large Hadron Collider.

    hep-phJHEP(2021)·11 citations
28. 28*

    Probing Relativistic Axions from Transient Astrophysical Sources

    Joshua Eby🇯🇵 · Satoshi Shirai🇯🇵 · Yevgeny V. Stadnik🇯🇵 · Volodymyr Takhistov🇯🇵

    Emission of relativistic axions from transient sources, such as axion star explosions, can lead to observable signatures. We show that axion bursts from collapsing axion stars can be detectable over the wide range of axion masses $10^{-15}\text{eV}\lesssim m\lesssim 10^{-7}\text{eV}$ in laboratory experiments, such as ABRACADABRA, DMRadio and SHAFT. The detection of axion bursts could provide new insights into the fundamental axion potential, which is challenging to probe otherwise. An ensemble of bursts in the distant past would give rise to a diffuse axion background distinct from the usual cold axion DM. Coincidence with other signatures would provide a new window into multi-messenger astronomy.

    hep-phastro-ph.COastro-ph.HEhep-exPLB(2022)·40 citations
29. 29*

    Baryogenesis via relativistic bubble walls

    Aleksandr Azatov🇮🇹 · Miguel Vanvlasselaer🇮🇹 · Wen Yin🇯🇵

    We present a novel mechanism which leads to the baryon asymmetry generation during the strong first order phase transition. If the bubble wall propagates with ultra-relativistic velocities, it has been shown that it can produce states much heavier than the scale of the transition and that those states are then out-of-equilibrium. In this paper, we show that the production mechanism can also induce CP-violation at one-loop level. We calculate those CP violating effects during the heavy particle production and show, that combined with baryon number violating interactions, those can lead to successful baryogenesis. Two models based on this mechanism are constructed and their phenomenology is discussed. Stochastic gravitational wave signals turn out to be generic signatures of this type of models.

    hep-phastro-ph.COJHEP(2021)·111 citations
30. 30*

    FCC-ee overview: new opportunities create new challenges

    Alain Blondel🇫🇷 · Patrick Janot🇨🇭

    With its high luminosity, its clean experimental conditions, and a range of energies that cover the four heaviest particles known today, FCC-ee offers a wealth of physics possibilities, with high potential for discoveries. The FCC-ee is an essential and complementary step towards a 100 TeV hadron collider, and as such offers a uniquely powerful combined physics program. This vision is the backbone of the 2020 European Strategy for Particle Physics. One of the main challenges is now to design experimental systems that can, demonstrably, fully exploit these extraordinary opportunities.

    ↳ hep-exhep-phEur.Phys.J.Plus(2022)·92 citations
31. 31*

    Primordial nucleosynthesis with varying fundamental constants: Solutions to the Lithium problem and the Deuterium discrepancy

    M. Deal🇵🇹 · C. J. A. P. Martins🇵🇹

    The success of primordial nucleosynthesis has been limited by the long-standing Lithium problem. We use a self-consistent perturbative analysis of the effects of relevant theoretical parameters on primordial nucleosynthesis, including variations of nature's fundamental constants, to explore the problem and its possible solutions, in the context of the latest observations and theoretical modeling. We quantify the amount of depletion needed to solve the Lithium problem, and show that transport processes of chemical elements in stars are able to account for it. Specifically, the combination of atomic diffusion, rotation and penetrative convection allows us to reproduce the lithium surface abundances of Population II stars, starting from the primordial Lithium abundance. We also show that even with this depletion factor there is a preference for a value of the fine-structure constant at this epoch that is larger than the current laboratory one by a few parts per million of relative variation, at the two to three standard deviations level of statistical significance. This preference is driven by the recently noticed discrepancy between the best-fit values for the baryon-to-photon ratio (or equivalently the Deuterium abundance) inferred from cosmic microwave background and primordial nucleosynthesis analyses, and is largely insensitive to the Helium-4 abundance. We thus conclude that the Lithium problem most likely has an astrophysical solution, while the Deuterium discrepancy provides a possible hint of new physics.

    ↳ astro-ph.COhep-phAstron.Astrophys.(2021)·24 citations
32. 32*

    Quantum gravity and the square of Bell operators

    S. Aghababaei🇮🇷 · H. Moradpour🇮🇷 · H. Shabani🇮🇷

    The Bell's inequality is a strong criterion to distinguish classical and quantum mechanical aspects of reality. Its violation is the net effect of the existence of non-locality in systems, an advantage for quantum mechanics (QM) over classical physics. The quantum mechanical world is under the control of the Heisenberg uncertainty principle (HUP) that is generalized by quantum gravity (QG) scenarios, called generalized uncertainty principle (GUP). Here, the effects of GUP on the square of Bell operators of qubits and qutrits are studied. The achievements claim that the violation quality of the square of Bell inequalities may be a tool to get a better understanding of the quantum features of gravity. In this regard, it is obtained that the current accuracy of the Stern-Gerlach experiments implies upper bounds on the values of the GUP parameters.

    ↳ quant-phgr-qchep-phQuant.Inf.Proc.(2022)·4 citations
33. 33*

    Tidal deformability of dressed black holes and tests of ultralight bosons in extended mass ranges

    V. De Luca🇨🇭 · P. Pani🇮🇹

    The deformability of a compact object under the presence of a tidal perturbation is encoded in the tidal Love numbers (TLNs), which vanish for isolated black holes in vacuum. We show that the TLNs of black holes surrounded by matter fields do not vanish and can be used to probe the environment around binary black holes. In particular, we compute the TLNs for the case of a black hole surrounded by a scalar condensate under the presence of scalar and vector tidal perturbations, finding a strong power-law behavior of the TLN in terms of the mass of the scalar field. Using this result as a proxy for gravitational tidal perturbations, we show that future gravitational-wave detectors like the Einstein Telescope and LISA can impose stringent constraints on the mass of ultralight bosons that condensate around black holes due to accretion or superradiance. Interestingly, LISA could measure the tidal deformability of dressed black holes across the range from stellar-mass ($\approx 10^2{M}_{\odot }$) to supermassive ($\approx 10^7{M}_{\odot }$) objects, providing a measurement of the mass of ultralight bosons in the range $(10^{-17}-10^{-13})\mathrm{eV}$ with less than $10\%$ accuracy, thus filling the gap between other superradiance-driven constraints coming from terrestrial and space interferometers. Altogether, LISA and Einstein Telescope can probe tidal effects from dressed black holes in the combined mass range $(10^{-17}-10^{-11})\mathrm{eV}$.

    ↳ gr-qcastro-ph.HEhep-phJCAP(2021)·92 citations
34. 34*

    Cluster and hyper-cluster production in relativistic heavy-ion collisions within the Parton-Hadron-Quantum-Molecular-Dynamics approach

    Susanne Gläßel🇩🇪 · Viktar Kireyeu🇷🇺 · Vadim Voronyuk🇷🇺 · Jörg Aichelin🇫🇷 · Christoph Blume🇩🇪 · Elena Bratkovskaya🇩🇪 · Gabriele Coci🇩🇪 · Vadim Kolesnikov🇷🇺 · Michael Winn🇫🇷

    We study cluster and hypernuclei production in heavy-ion collisions at relativistic energies employing the Parton-Hadron-Quantum-Molecular-Dynamics (PHQMD) approach, a microscopic n-body transport model based on the QMD propagation of the baryonic degrees of freedom with density dependent 2-body potential interactions. All other ingredients of PHQMD, including the collision integral and the treatment of the quark-gluon plasma (QGP) phase, are adopted from the Parton-Hadron-String Dynamics (PHSD) approach. In PHQMD the cluster formation occurs dynamically, caused by the interactions. The clusters are recognized by the Minimum Spanning Tree (MST) algorithm. We present the PHQMD results for cluster and hypernuclei formation in comparison with the available experimental data at AGS, SPS, RHIC-BES and RHIC fixed target energies. We also provide predictions on cluster production for the upcoming FAIR and NICA experiments. PHQMD allows to study the time evolution of formed clusters and the origin of their production, which helps to understand how such weakly bound objects are formed and survive in the rather dense and hot environment created in heavy-ion collisions. It offers therefore an explanation of the 'ice in the fire' puzzle.

    ↳ nucl-thhep-phPRC(2022)·62 citations
35. 35*

    Neutrino-electron magnetohydrodynamics in an expanding Universe

    L. M. Perrone (1 and 2)🇮🇹 · G. Gregori (2)🇬🇧 · B. Reville (3)🇩🇪 · L. O. Silva (4)🇵🇹 · R. Bingham (5 and 6) ((1) Department of Applied Mathematics and Theoretical Physics, University of Cambridge, (2) Department of Physics, University of Oxford, (3) Max-Planck-Institut für Kernphysik, (4) GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, (5) Rutherford Appleton Laboratory, (6) Department of Physics, University of Strathclyde)🇬🇧

    We derive a new model for neutrino-plasma interactions in an expanding universe that incorporates the collective effects of the neutrinos on the plasma constituents. We start from the kinetic description of a multi-species plasma in the flat Friedmann-Robertson-Walker metric, where the particles are coupled to neutrinos through the charged- and neutral-current forms of the weak interaction. We then derive the fluid equations and specialize our model to (a) the lepton epoch, where we consider a pair electron-positron plasma interacting with electron (anti-)neutrinos, and (b) after the electron-positron annihilation, where we model an electron-proton plasma and take the limit of slow ions and inertia-less electrons to obtain a set of neutrino-electron magnetohydrodynamics (NEMHD) equations. In both models, the dynamics of the plasma is affected by the neutrino motion through a ponderomotive force and, as a result, new terms appear in the induction equation that can act as a source for magnetic field generation in the early universe. A brief discussion on the possible applications of our model is proposed.

    ↳ astro-ph.COastro-ph.HEhep-phPRD(2021)·6 citations
36. 36*

    Parity Violating Non-Gaussianity from Axion-Gauge Field Dynamics

    Ogan Özsoy🇨🇿

    We study scalar-tensor-tensor and tensor-scalar-scalar three point cross correlations generated by the dynamics of a transiently rolling spectator axion-$\mathrm{U}(1)$ gauge field model during inflation. In this framework, tensor and scalar fluctuations are sourced by gauge fields at the non-linear level due to gravitational interactions, providing a chiral background of gravitational waves while keeping the level of scalar fluctuations at the observationally viable levels at CMB scales. We show that the gravitational couplings between the observable sector and gauge fields can also mediate strong correlations between scalar and tensor fluctuations, generating an amplitude for the mixed type three-point functions that is parametrically larger -- $f_{\mathrm{NL}}\simeq \mathcal{O}(1-10)(r/0.01{)}^{3/2}$-- compared to the single-field realizations of inflation. As the amplification of the gauge field sources are localized around the time of horizon exit, the resulting mixed bispectra are peaked {\it close} to the equilateral configurations. The shape dependence, along with the scale dependence and the parity violating nature of the mixed bispectra can serve as a distinguishing feature of the underlying axion-gauge field dynamics and suggest a careful investigation of their signatures on the CMB observables including cross correlations between temperature T and E,B polarization modes.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2021)·28 citations
37. 37*

    Generalizing event shapes: In search of lost collider time

    Gregory Korchemsky🇫🇷 · Emery Sokatchev🇫🇷 · Alexander Zhiboedov🇨🇭

    We introduce a new class of collider-type observables in conformal field theories which we call generalized event shapes. They are defined as matrix elements of light-ray operators that are sensitive to the longitudinal, or time-dependent, structure of the state produced in the collision. Generalized event shapes can be studied using both correlation functions and scattering amplitudes. They are infrared finite and smoothly transit over to the familiar event shapes. We compute them in planar $\mathcal{N}=4$ super-Yang-Mills theory at weak and strong coupling, and study their physical properties. We show that at strong coupling both the stringy and quantum-gravitational corrections to the energy-energy correlation exhibit longitudinal broadening that manifests itself through the presence of long-time tails in the energy flux measured by the detectors.

    ↳ hep-thhep-phJHEP(2022)·48 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.