Wed·May 4, 2022Wednesday·May 4, 2022

1. 01*

   Freeze-in Dark Matter via Light Dirac Neutrino Portal

   Anirban Biswas🇰🇷 · Debasish Borah🇮🇳 · Nayan Das🇮🇳 · Dibyendu Nanda🇰🇷

   We propose a scenario where dark matter (DM) can be generated non-thermally due to the presence of a light Dirac neutrino portal between the standard model (SM) and dark sector particles. The SM is minimally extended by three right handed neutrinos (${\nu }_R$), a Dirac fermion DM candidate ($\psi$) and a complex scalar ($\varphi$), transforming non-trivially under an unbroken ${\mathbb{Z}}_4$ symmetry while being singlets under the SM gauge group. While DM and ${\nu }_R$ couplings are considered to be tiny in order to be in the non-thermal or freeze-in regime, $\varphi$ can be produced either thermally or non-thermally depending upon the strength of its Higgs portal coupling. We consider both these possibilities and find out the resulting DM abundance via freeze-in mechanism to constrain the model parameters in the light of Planck 2018 data. Since the interactions producing DM also produces relativistic ${\nu }_R$, we check the enhanced contribution to the effective relativistic degrees of freedom $\Delta {\mathrm{N}}_{\mathrm{eff}}$ in view of existing bounds as well as future sensitivities. We also check the stringent constraints on free-streaming length of such freeze-in DM from structure formation requirements. Such constraints can rule out DM mass all the way up to $\mathcal{O}(100\mathrm{keV})$ keeping the $\Delta {\mathrm{N}}_{\mathrm{eff}}\le \mathcal{O}(10^{-3})$, out of reach from near future experiments. Possible extensions of this minimal model can lead to observable $\Delta {\mathrm{N}}_{\mathrm{eff}}$ which can be probed at next generation experiments.

   hep-phastro-ph.COPRD(2023)·30 citations
2. 02*

   Experimental determination of the QCD effective charge ${\alpha }_{g_1}(Q)$

   A. Deur🇺🇸 · V. Burkert🇺🇸 · J.P. Chen🇺🇸 · W. Korsch🇺🇸

   The QCD effective charge ${\alpha }_{g_1}(Q)$ is an observable that characterizes the magnitude of the strong interaction. At high momentum $Q$, it coincides with the QCD running coupling ${\alpha }_{\mathrm{s}}(Q)$. At low $Q$, it offers a nonperturbative definition of the running coupling. We have extracted ${\alpha }_{g_1}(Q)$ from measurements carried out at Jefferson Lab that span the very low to moderately high $Q$ domain, $0.14\le Q\le 2.18$ GeV. The precision of the new results is much improved over the previous extractions and the reach in $Q$ at the lower end is significantly expanded. The data show that ${\alpha }_{g_1}(Q)$ becomes $Q$-independent at very low $Q$. They compare well with two recent predictions of the QCD effective charge based on Dyson-Schwinger equations and on the AdS/CFT duality.

   hep-phhep-exnucl-exParticles(2022)·45 citations
3. 03*

   Searching for anomalous top quark interactions with proton tagging and timing detectors at the LHC

   Cristian Baldenegro🇫🇷 · Andrea Bellora🇮🇹 · Sylvain Fichet🇧🇷 · Gero von Gersdorff🇧🇷 · Michael Pitt🇨🇭 · Christophe Royon🇺🇸

   We study the LHC sensitivity to new broad neutral resonances produced in two-photon fusion and decaying to a top quark pair, $\gamma \gamma \to t\bar{t}$. This is probed in central exclusive $t\bar{t}$ production in proton-proton collisions, $pp\to pt\bar{t}p$. We use the tagging of the intact protons by PPS (CMS) and AFP (ATLAS) and consider the semi-leptonic $t\bar{t}$ channel. The sensitivity is also mapped onto a set of dimension-8 $\gamma \gamma t\bar{t}$ operators in the large mass limit. Using the kinematical correlations between the intact protons and the reconstructed $t\bar{t}$ system, we obtain a sensitivity to the couplings of the dimension-8 operators of $1.4\cdot 10^{-11}{\mathrm{GeV}}^{-4}$ at 95% CL. The sensitivity to the anomalous couplings is significantly improved down to about $7\cdot 10^{-12}{\mathrm{GeV}}^{-4}$ if the proton time-of-flight is known with a precision of 20 ps in future measurements. The 95% CL sensitivity to broad neutral resonances reaches masses of order $1500\mathrm{GeV}$ when using timing information.

   hep-phJHEP(2022)·16 citations
4. 04*

   Exotic heavy hadrons with a three-body nature

   A. Martinez Torres🇧🇷 · Brenda B. Malabarba🇧🇷 · Xiu-Lei Ren🇩🇪 · K. P. Khemchandani🇧🇷 · L. S. Geng🇨🇳

   In this talk we present a summary of our latest results on the investigation of three-body systems with explicit/hidden charm and with explicit/hidden strangeness. To be more concrete, in case of explicit strangeness quantum number, we pay attention on the $KDD$ and $KD{\bar{D}}^{\ast }$ systems, where, in the former, a charm $+2$, isospin $1/2$ and strangeness $+1$ state is obtained with a mass around 4140 MeV, while in the latter, a $K^{\ast }$ state, with hidden charm, and a mass close to 4307 MeV is found. In case of hidden strangeness, the $DK\bar{K}$ system is studied, while in the hidden charm and no strangeness quantum numbers sector, the $ND{\bar{D}}^{\ast }$ system is investigated. In the former a meson $D$ with mass around 2900 MeV is found to be generated, while in the latter several $N^{\ast }$ and ${\Delta }^{\ast }$ states with hidden charm are obtained with masses about $4600$ MeV. All these states constitute predictions of our model and future experimental confirmation of them would be relevant to elucidate the properties of the strong interaction in the presence of heavy quarks.

   hep-phnucl-thPoS(2022)·0 citations
5. 05*

   More on Fake GUT

   Masahiro Ibe🇯🇵 · Satoshi Shirai🇯🇵 · Motoo Suzuki🇯🇵 · Keiichi Watanabe🇯🇵 · Tsutomu T. Yanagida🇨🇳

   It is remarkable that the matter fields in the Standard Model (SM) are apparently unified into the $\mathrm{SU}(5)$ representations. A straightforward explanation of this fact is to embed all the SM gauge groups into a simple group containing $\mathrm{SU}(5)$, i.e., the grand unified theory (GUT). Recently, however, a new framework "fake GUT" has been proposed. In this new framework, the apparent matter unification can be explained by a chiral gauge group $G$, $G\supset \mathrm{SU}(5)$. We emphasize that the SM matter fields are not necessarily embedded into the chiral representations to explain the apparent unification. In this paper, we discuss details of concrete realizations of the fake GUT model. We first study the model based on $\mathrm{SU}(5)\times \mathrm{U}(2{)}_H$, where $\mathrm{SU}(3{)}_c$ in the SM is from $\mathrm{SU}(5)$ while $\mathrm{SU}(2{)}_L\times \mathrm{U}(1{)}_Y$ are from the diagonal subgroups of $\mathrm{SU}(5)\times \mathrm{U}(2{)}_H$. We also extend this model to the one based on a semi-simple group, $\mathrm{SU}(5)\times \mathrm{SU}(3{)}_H$, so that $\mathrm{U}(2{)}_H$ is embedded in $\mathrm{SU}(3{)}_H$. We also show that this framework predicts rather different decay patterns of the proton, compared to the conventional GUT.

   hep-phJHEP(2022)·4 citations
6. 06*

   Hadronic loop effects to excited scalar charmed mesons revisited

   Mohammad H. Alhakami🇸🇦 · Numa A. Althubiti🇸🇦 · Nwuyer A. Al-shammari🇸🇦

   We re-examine the hadronic loop effects to the masses of $D_0^{\ast }$ and $D_{s0}^{\ast }$ calculated in quark models in the framework of heavy meson chiral perturbation theory (HMCHPT). The inaccuracy in the choice of the argument of the chiral loop functions in previous works is corrected. Our calculations consider the full one-loop corrections that appear at leading order in the chiral expansion of the effective Lagrangian. Unlike previous approaches, ours leads to satisfactory results in explaining the low mass of the observed scalar charm states reported by the Particle Data Group (PDG). It is found that the mass shift of bare $D_{s0}^{\ast }$ ($D_0^{\ast }$) state is mainly due to the $DK$ ($D\pi$) loop corrections for values of the couplings that are compatible with the measured ones. We show why previous approaches of using HMCHPT in studying mass shift effects due to chiral loops gave unsatisfactory results.

   hep-phJ.Phys.G(2023)·2 citations
7. 07*

   Compatibility of muon $g-2$, $W$ mass anomaly in type-X 2HDM

   Jongkuk Kim🇰🇷

   Recently CDF II Collaboration reported that they measured W boson mass precisely. The measurement is deviated from the Standard Model (SM) Prediction at 7$\sigma$. Also, the recent FNAL measurement of the muon magnetic moment shows a $4.2\sigma$ deviation. To resolve the W boson as well as the muon $(g-2)$ anomalies, we explore the type-X two Higgs doublet model (2HDM). We analyze the $(m_A,\tan \beta )$ parameter space of the type-X 2HDM consistent with the muon $(g-2)$, lepton universality test and recent $W$ boson mass measurments from the CDF II collaboration. We find that the measurement of the $h\to AA$ branching ratio gives a strong lower mass bound on $m_H$.

   hep-phPLB(2022)·41 citations
8. 08*

   Single Photon Production at Hadron Colliders at NNLO QCD with Realistic Photon Isolation

   X. Chen🇩🇪 · T. Gehrmann🇨🇭 · E.W.N. Glover🇬🇧 · M. Höfer🇩🇪 · A. Huss🇨🇭 · R. Schürmann🇨🇭

   Isolated photons at hadron colliders are defined by permitting only a limited amount of hadronic energy inside a fixed-size cone around the candidate photon direction. This isolation criterion admits contributions from collinear photon radiation off QCD partons and from parton-to-photon fragmentation processes. We compute the NNLO QCD corrections to isolated photon and photon-plus-jet production, including these two contributions. Our newly derived results allow us to reproduce the isolation prescription used in the experimental measurements, performing detailed comparisons with data from the LHC experiments. We quantify the impact of different photon isolation prescriptions, including no isolation at all, on photon-plus-jet cross sections and discuss possible measurements of the photon fragmentation functions at hadron colliders.

   hep-phJHEP(2022)·31 citations
9. 09*

   Role of dimension-eight operators in an EFT for the 2HDM

   Sally Dawson🇺🇸 · Duarte Fontes🇺🇸 · Samuel Homiller🇺🇸 · Matthew Sullivan🇺🇸

   The Standard Model effective field theory (SMEFT) is the tool of choice for studying deviations of Higgs couplings from the Standard Model predictions. The SMEFT is an expansion in an infinite tower of higher dimension operators, which is typically truncated at dimension-6. We consider the effective theory including dimension-8 operators and examine the matching to the 2 Higgs Doublet Model (2HDM) that is assumed to be valid at some high scale. Both the limits from the direct production of single Higgs bosons and the indirect limits on the Higgs tri-linear coupling are considered in the context of the SMEFT matched to the 2HDM, and the importance of the assumptions about the expansions in powers of the high scale are examined numerically.

   hep-phPRD(2022)·65 citations
10. 10*

    Improved stellar limits on a light CP-even scalar

    Shyam Balaji🇫🇷 · P. S. Bhupal Dev🇺🇸 · Joseph Silk🇫🇷 · Yongchao Zhang🇨🇳

    We derive improved stellar luminosity limits on a generic light CP-even scalar field $S$ mixing with the Standard Model (SM) Higgs boson from the supernova SN1987A, the Sun, red giants (RGs) and white dwarfs (WDs). For the first time, we include the geometric effects for the decay and absorption of $S$ particles in the stellar interior. For SN1987A and the Sun, we also take into account the detailed stellar profiles. We find that a broad range of the scalar mass and mixing angle can be excluded by our updated astrophysical constraints. For instance, SN1987A excludes $1.0\times 10^{-7}\lesssim \sin \theta \lesssim 3.0\times 10^{-5}$ and scalar mass up to 219 MeV, which covers the cosmological blind spot with a high reheating temperature. The updated solar limit excludes the mixing angle in the range of $1.5\times 10^{-12}<\sin \theta <1$, with scalar mass up to 45 keV. The RG and WD limits are updated to $5.3\times 10^{-13}<\sin \theta <0.39$ and $2.8\times 10^{-18}<\sin \theta <1.8\times 10^{-4}$, with scalar mass up to 392 keV and 290 keV, respectively.

    hep-phastro-ph.COastro-ph.SRJCAP(2022)·55 citations
11. 11*

    NNLO QCD corrections to $Wb\bar{b}$ production at the LHC

    Heribertus Bayu Hartanto🇬🇧 · Rene Poncelet🇬🇧 · Andrei Popescu🇬🇧 · Simone Zoia🇮🇹

    We compute theoretical predictions for the production of a W-boson in association with a bottom-quark pair at hadron colliders at next-to-next-to-leading order (NNLO) in QCD, including the leptonic decay of the W-boson, while treating the bottom quark as massless. This calculation constitutes the very first $2\to 3$ process with a massive external particle to be studied at such a perturbative order. We derive an analytic expression for the required two-loop five-particle amplitudes in the leading colour approximation employing finite-field methods. Numerical results for the cross section and differential distributions are presented for the Large Hadron Collider at $\sqrt{s}=8$ TeV. We observe an improvement of the perturbative convergence for the inclusive case and for the prediction with a jet veto upon the inclusion of the NNLO QCD corrections.

    hep-phPRD(2022)·60 citations
12. 12*

    Inflationary Gravitational Leptogenesis

    Raymond T. Co🇺🇸 · Yann Mambrini🇫🇷 · Keith A. Olive🇺🇸

    We consider the generation of the baryon asymmetry in models with right-handed neutrinos produced through gravitational scattering of the inflaton during reheating. The right-handed neutrinos later decay and generate a lepton asymmetry, which is partially converted to a baryon asymmetry by Standard Model sphaleron processes. We find that a sufficient asymmetry can be generated for a wide range of right-handed neutrino masses and reheating temperatures. We also show that the same type of gravitational scattering produces Standard Model Higgs bosons, which can achieve inflationary reheating consistent with the production of a baryon asymmetry.

    hep-phastro-ph.COPRD(2022)·51 citations
13. 13*

    Event Generation and Density Estimation with Surjective Normalizing Flows

    Rob Verheyen🇬🇧

    Normalizing flows are a class of generative models that enable exact likelihood evaluation. While these models have already found various applications in particle physics, normalizing flows are not flexible enough to model many of the peripheral features of collision events. Using the framework of Nielsen et al. (2020), we introduce several surjective and stochastic transform layers to a baseline normalizing flow to improve modelling of permutation symmetry, varying dimensionality and discrete features, which are all commonly encountered in particle physics events. We assess their efficacy in the context of the generation of a matrix element-level process, and in the context of anomaly detection in detector-level LHC events.

    hep-phSciPost Phys.(2022)·47 citations
14. 14*

    New $W$-Boson mass in the light of doubly warped braneworld model

    Basabendu Barman🇨🇴 · Ashmita Das🇮🇳 · Soumitra Sengupta🇮🇳

    The recent observation by CDF collaboration has disclosed a modification in the mass of the $W$ boson. In this regard we show that this modification in the mass of the $W$ boson can be well explained in the background of a 6-dimensional warped geometry model, where the double warping is associated with the two extra spatial dimensions. We consider that all the Standard Model fields are residing in the bulk, where the bulk Higgs field gives rise to the spontaneous symmetry breaking in the 6-dimensional spacetime. Allowing a little hierarchy between the two moduli we exactly obtain the observed mass for the $W$ boson, which is identified as the lowest lying Kaluza-Klein mass mode of the bulk $W$ boson on the $(3+1)$ dimensional visible brane. The essential feature of the 5-dimensional Randall-Sundrum scenario such as the resolution of the gauge hierarchy problem without introducing any intermediate scale between the Planck and the TeV scale, remains intact.

    hep-ph17 citations
15. 15*

    CDF $W$ boson mass and muon $g-2$ in type-X two-Higgs-doublet model with a Higgs-phobic light pseudoscalar

    Jinheung Kim🇰🇷 · Soojin Lee🇰🇷 · Prasenjit Sanyal🇰🇷 · Jeonghyeon Song🇰🇷

    The recent measurement of the $W$ boson mass by the CDF collaboration adds an anomaly to the long-standing discrepancy in the muon anomalous magnetic moment, $\Delta a_{\mu }$. Although type-X in the two-Higgs-doublet model provides an attractive solution to $\Delta a_{\mu }$ through a light pseudoscalar $A$, the model confronts the exotic Higgs decays of $h\to AA$ and the lepton flavor universality data in the $\tau$ and $Z$ decays. To save the model, we propose that the light pseudoscalar be Higgs-phobic. Through the random scanning over the entire parameter space, we perform a comparative study of the Higgs-phobic type-X with and without the CDF $m_W$ measurement, called the CDF and PDG cases respectively. Both cases can explain the two anomalies as well as all the other constraints but have significant differences in the finally allowed parameter space. For example, a small region with almost degenerate masses of new Higgs bosons around 100 GeV is allowed only in the PDG case. The cutoff scale of the model is also studied via the analysis of renormalization group equations, which reaches up to $10^5\mathrm{GeV}$ ($10^7\mathrm{GeV}$) in the CDF (PDG) case. Since the dominant decay modes are $A\to \tau \tau$, $H\to ZA$, and $H^{\pm }\to W^{\pm }A$ in most of the viable parameter space, we propose the $4\tau +V{V}^{\prime }$ states as the golden discovery channel at the LHC.

    hep-phhep-exPRD(2022)·47 citations
16. 16*

    Role of slow, out-of-equilibrium modes on the dynamic structure factor near the QCD critical point

    Golam Sarwar🇮🇳 · Md Hasanujjaman🇮🇳 · Jan-e Alam🇮🇳

    The role of slow out of equilibrium modes (OEM), introduced to extend the validity of hydrodynamics near the QCD critical point on the power spectrum of dynamical density fluctuations has been studied. We have used the equation of motion of slow modes for the situation when the extensive nature of thermodynamics is not altered due to the introduction of OEM. We find that the extensivity condition puts an extra constraint on the coupling of OEM with the four divergence of velocity. The dynamic structure factor (Snn) in presence of the OEM shows four Lorentzian peaks asymmetrically positioned about $\omega (\text{frequency})=0$, whereas the dynamic structure factor without the presence of any OEM shows three well-known Lorentzian peaks. The width of the peaks are reduced in presence of OEM. We find that the asymmetric peaks originate due to the coupling of the out-of-equilibrium modes with the hydrodynamic modes. It is also shown that the OEM has negligible effects on Snn if first order hydrodynamics (relativistic Navier-Stokes) is used. The introduction of OEM reduces the width of the Rayleigh peak indicating the reduction in the decay rate of the fluctuation which leads to slowing down, a well-known characteristics of the critical end point (CEP).

    ↳ nucl-thhep-phPRD(2022)·3 citations
17. 17*

    Detailed Study of Quark-Hadron Duality in Spin Structure Functions of the Proton and Neutron

    Victoria Lagerquist🇺🇸 · Sebastian E. Kuhn🇺🇸 · Nobuo Sato🇺🇸

    In this paper, we present for the first time comprehensive and detailed results on the correspondence between the extrapolated deep inelastic structure function $g_1$ of both the proton and the neutron with the same quantity measured in the nucleon resonance region. We use a QCD parameterization of the world data on DIS spin structure functions, extrapolated into the nucleon resonance region and averaged over various intervals in the scaling variable $x$. We compare the results with the large data set collected in the quark-hadron transition region by the CLAS collaboration, averaged over the same intervals. We present this comparison as a function of the momentum transfer $Q^2$. We find that, depending on the averaging interval and the minimum momentum transfer chosen, a clear transition to quark-hadron duality can be observed in both nucleon species. Furthermore, we show, for the first time, the scaling behavior of $g_1$ measured in the resonance region at sufficiently high momentum transfer. Our results can be used to quantify the deviations from the applicability of pQCD for data taken at moderate energies, and help with extraction of quark distribution functions from such data.

    ↳ nucl-exhep-phnucl-thPRC(2023)·4 citations
18. 18*

    Complete complementarity relations for quantum correlations in neutrino oscillations

    V.A.S.V. Bittencourt🇩🇪 · M. Blasone🇮🇹 · S. De Siena🇮🇹 · C. Matrella🇮🇹

    We analyze quantum correlations and quantum coherence in neutrino oscillations. To this end, we exploit complete complementarity relations (CCR) that fully characterize the interplay between different correlations encoded in a quantum system both for pure and mixed states. We consider the CCR for neutrino oscillations both in the case of plane-waves (pure state) and of wave packets (mixed state). In this last case we find a complex structure of correlations depending on the mixing angle, and we show the connection with the non local advantage of quantum coherence, a relevant quantifier of coherence.

    ↳ quant-phhep-phhep-thEPJC(2022)·32 citations
19. 19*

    Novel cosmological bounds on thermally-produced axion-like particles

    Luca Caloni🇮🇹 · Martina Gerbino🇮🇹 · Massimiliano Lattanzi🇮🇹 · Luca Visinelli🇨🇳

    We constrain the coupling of thermally-produced axion-like particles (here axions) with photons and gluons, using data from the cosmic microwave background (CMB) spectra and baryon acoustic oscillations. The axion possesses an explicit soft breaking mass term and it is produced thermally in the early Universe from either axion-photon or axion-gluon processes, accounting for the recent progresses in the field. We derive the most stringent bounds on the axion-gluon coupling to date on the mass range considered $10^{-4}\lesssim m_a/\mathrm{eV}\lesssim 100$, superseding the current bounds from SN1987A. The bounds on the axion-photon coupling are competitive with the results from the CAST collaboration for the axion mass $m_a\gtrsim 3$eV. We comment on the forecast reaches that will be available given the sensitivity of future CMB-S4 missions.

    ↳ astro-ph.COhep-phJCAP(2022)·72 citations
20. 20*

    Phase Information in Cosmological Collider Signals

    Zhehan Qin🇨🇳 · Zhong-Zhi Xianyu🇨🇳

    Massive particles produced during the cosmic inflation can imprint in the primordial non-Gaussianities as characteristic oscillating functions of various momentum ratios, known as cosmological collider signals. We initiate a study of the phase of the oscillating signals which can be unambiguously defined and measured. The phase can provide useful new information about the spin and the couplings of the intermediate heavy particles that cannot be obtained from the signal frequency and angular dependences alone. We also present new analytical results for full nonlocal signals from two typical 1-loop processes, enabling precise determination of the signal phase away from the squeezed limit.

    ↳ hep-thastro-ph.COhep-phJHEP(2022)·77 citations
21. 21*

    Induced gravitational waves from slow-roll inflation after an enhancing phase

    Shyam Balaji🇫🇷 · Guillem Domenech🇮🇹 · Joseph Silk🇫🇷

    The primordial spectrum of fluctuations may present a large peak as a result of enhancing features during inflation. This may include, but is not limited to, bumps in the inflaton's potential, phases of ultra-slow-roll or turns in multi-field space. However, in many models, inflation does not end immediately after the enhancing feature and it is likely to continue with a second phase of slow-roll. We show that the resulting induced gravitational waves may probe the primordial spectrum from the second inflationary phase, even if its amplitude is too small to directly induce detectable gravitational waves. This is because, if there are sharp peaks in the primordial spectrum, the total gravitational wave spectrum is not simply the sum of gravitational waves induced by a peaked and scale-invariant primordial spectra separately, but cross terms from interaction between these modes also become important. We also find that such cross terms always have a characteristic slope. We discuss the parameter space that may be probed by future gravitational waves detectors in the presence of these signals.

    ↳ astro-ph.COhep-phJCAP(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.