Wed·Oct 20, 2021Wednesday·October 20, 2021

1. 01*

   $J$-factors for Velocity-dependent Dark Matter

   Bradly Boucher🇺🇸 · Jason Kumar🇺🇸 · Van B. Le🇺🇸 · Jack Runburg🇺🇸

   If dark matter annihilates with a velocity-dependent cross section within a subhalo, then the magnitude and angular distribution of the resulting photon signal will change. These effects are encoded in the $J$-factor. In this work we compute the $J$-factor for a variety of choices for the cross section velocity-dependence, and for a variety of choices for the dark matter profile, including generalized Navarro-Frenk-White (NFW), Einasto, Burkert and Moore. We include the results of these computations as data products alongside the article. We find that the angular distribution of a future signal would depend on the velocity-dependence of the annihilation cross section more strongly for cuspy profiles than for cored profiles. Interestingly, we find that for a density profile with an inner slope power law steeper than 4/3, Sommerfeld-enhanced annihilation in the Coulomb limit leads to a divergence at the center, requiring a more detailed treatment of departure from the Coulomb limit.

   hep-phastro-ph.COPRD(2022)·19 citations
2. 02*

   Brief on Dark Matter in the Type Ib Seesaw Model: a GeV-scale Dirac neutrino portal

   Bowen Fu🇬🇧

   The type Ib seesaw, as an alternative explanation to the origin of neutrino mass, provides a new intriguing way to connect the neutrino physics to cosmology. In this proceeding, we consider a minimal type Ib seesaw model where the effective neutrino mass operator involves two different Higgs doublets and a heavy Dirac mass. We propose a minimal dark matter extension of this model, in which the Dirac heavy neutrino is coupled to a dark Dirac fermion and a dark complex scalar field, both odd under a discrete $Z_2$ symmetry, where the lighter one serves as a dark matter candidate. Focussing on the fermionic dark matter case, we explore the parameter space of the seesaw Yukawa couplings, the neutrino portal couplings and dark scalar to dark fermion mass ratio, where correct dark matter relic abundance can be produced by the freeze-in mechanism. By considering the mixing between the standard model neutrinos and the heavy neutrino, a connection can be built between dark matter production and laboratory experiments.

   hep-phPoS(2022)·0 citations
3. 03*

   Earth Shielding and Daily Modulation from Electrophilic Boosted Dark Particles

   Yifan Chen🇨🇳 · Bartosz Fornal🇺🇸 · Pearl Sandick🇺🇸 · Jing Shu🇨🇳 · Xiao Xue🇩🇪 · Yue Zhao🇺🇸 · Junchao Zong🇨🇳

   Boosted dark particles of astrophysical origin can lead to nonstandard nuclear or electron recoil signals in direct detection experiments. %It has been shown that this interpretation successfully explains the excess of keV electron recoil events recently observed by the XENON1T experiment, and that a daily modulation of the signal in the detector is expected. We conduct an investigation of the daily modulation feature of a potential future signal of this type. In particular, we perform simulations of the dark particle interactions with electrons in atoms building up the Earth on its path to the detector, and provide in-depth predictions for the expected daily changes in the signal for various direct detection experiments, including XENONnT, PandaX, and LUX-ZEPLIN.

   hep-phastro-ph.HEhep-exPRD(2023)·22 citations
4. 04*

   Studying QCD modeling of uncertainties in particle spectra from dark-matter annihilation into jets

   Adil Jueid🇰🇷

   Motivated by various excesses observed by the Fermi-LAT and AMS collaborations, we perform a detailed analysis of QCD uncertainties on particle spectra from dark-matter annihilation (or decay) into jets. When annihilated to SM particles, the final-state annihilation products undergo various complicated processes such as QED and QCD bremsstrahlung, hadronisation, and hadron decays. These processes contain some intrinsic uncertainties which are usually difficult to model and which are neglected in physical analyses. First, we perform several re-tunings of the fragmentation function parameters. Then, we estimate two kinds of uncertainties: {\it (i)} perturbative from QCD showers and {\it (ii)} non-perturbative from hadronisation function. The results are tabulated for a wide range of dark matter masses, $m_{\chi }\in [10,10^5]\mathrm{GeV}$, and annihilation channels. They can be found on Zenodo: https://doi.org/10.5281/zenodo.3764809

   hep-phastro-ph.HEJ.Phys.Conf.Ser.(2021)·6 citations
5. 05*

   Hunting for the heavy quark spin symmetry partner of $Z_{cs}$

   Xu Cao🇨🇳 · Zhi Yang🇨🇳

   The discovery of a charged strange hidden-charm state $Z_{cs}$(3985) implies another higher $Z_{cs}^{\ast }$ state coupling to ${\bar{D}}_s^{\ast -}{D}^{\ast 0}+c.c$ under the heavy quark spin symmetry. In this paper we discuss a possible hunt for it with data taken at existing facilities. We point out a hint for $Z_{cs}^{\ast }$ in the data of ${\bar{B}}_s^0\to J/\psi K^{-}{K}^{+}$ at LHCb, though weak, in line with the production mechanism of pentaquark $P_c$. We also study the triangular singularity which would possibly enhance the production of $Z_{cs}^{\ast }$ in electron-positron collision. Surprisingly, the production rate of $Z_{cs}^{\ast }$ is expected to be maximum at the $e^{+}{e}^{-}$ center of mass energy of 4.648 GeV, which is lower than 4.681 GeV for $Z_{cs}$ due to the inverted coupling hierarchy of $D_{s1}\bar{D}K$ and $D_{s2}{\bar{D}}^{\ast }K$ in the triangle diagrams. Their bottom analogue under heavy quark flavor symmetry is also discussed. Our theoretical analysis would confront with future experiment of LHCb, BESIII, and Bell II.

   hep-phEPJC(2022)·9 citations
6. 06*

   Dark matter in a charged variant of the Scotogenic model

   Miguel Puerta🇪🇸

   Scotogenic models are among the most elegant and economic solutions that provide an explanation for two of the main open questions in particle physics: neutrino masses and dark matter (DM). In this work, after a brief discussion of the model, we present a phenomenological study of the DM candidate in a variant of the Scotogenic model. While in the original Scotogenic scenario the DM candidate can be fermionic or bosonic, only the latter is viable in this version. The presence of new charged states might reveal new regions in the parameter space compatible with current observations.

   hep-phJ.Phys.Conf.Ser.(2021)·1 citation
7. 07*

   Light Sterile Neutrinos

   Stefano Gariazzo🇮🇹

   We review the status of light sterile neutrino searches, motivated by the original Short BaseLine (SBL) anomalies. Here, we discuss how sterile neutrino properties can be constrained by different types of neutrino oscillation experiments (considering appearance or disappearance probes in different oscillation channels) and non-oscillation measurements. These latter include experiments aiming at obtaining a value for the absolute scale of neutrino masses ($\beta$ decay probes) and the indirect constraints that we could obtain from cosmological observations.

   hep-phJ.Phys.Conf.Ser.(2021)·6 citations
8. 08*

   Ultralight dark matter: constraints from gravitational waves and other astrophysical observations

   Tanmay Kumar Poddar🇮🇳

   The orbital period loss of the compact binary systems is the first indirect evidence of gravitational waves which agrees well with Einstein's general theory of relativity to a very good accuracy. However, there is less than one percent uncertainty in the measurement of orbital period loss from the general reltivistic prediction. Perihelion precession of planets, Gravitational light bending and Shapiro delay are three other successful tests of general relativity theory. Though there are uncertainties in the measurements of those observations from the general reltivistic predictions as well. To resolve these uncertainties, we assume radiation of ultralight axions and light gauge boson particles of $L_i-L_j$ type from those systems which can be a possible candidate of fuzzy dark matter. In this article, we obtain bounds on new physics parameters from those astrophysical observations.

   hep-phastro-ph.COgr-qcJ.Phys.Conf.Ser.(2021)·0 citations
9. 09*

   A general effective field theory description of $b\to s{l}^{+}{l}^{-}$ lepton universality ratios

   Gino Isidori🇨🇭 · Davide Lancierini🇨🇭 · Abhijit Mathad🇨🇭 · Patrick Owen🇨🇭 · Nicola Serra🇨🇭 · Rafael Silva Coutinho🇨🇭

   We construct an expression for a general lepton flavour universality (LFU) ratio, $R_X$, in $b\to s{l}^{+}{l}^{-}$ decays in terms of a series of hadronic quantities which can be treated as nuisance parameters. This expression allows to include any LFU ratio in global fits of $b\to s{l}^{+}{l}^{-}$ short-distance parameters, even in the absence of a precise knowledge of the corresponding hadronic structure. The absence of sizeable LFU violation and the approximate left-handed structure of the Standard Model amplitude imply that only a very limited set of hadronic parameters hamper the sensitivity of $R_X$ to a possible LFU violation of short-distance origin. A global $b\to s{l}^{+}{l}^{-}$ combination is performed including the measurement of $R_{pK}$ for the first time, resulting in a significance of new physics of $4.2\sigma$. In light of this, we evaluate the impact on the global significance of new physics using a set of experimentally promising non-exclusive $R_X$ measurements that LHCb can perform, and find that they can significantly increase the discovery potential of the experiment.

   hep-phhep-exPLB(2022)·20 citations
10. 10*

    Dark matter produced from neutrinos

    Marco Hufnagel🇧🇪 · Xun-Jie Xu🇨🇳

    In the presence of interactions between neutrinos and dark matter (DM), DM can potentially be produced via freeze-in from the neutrino sector. We investigate the implications of such a scenario for the evolution of both DM and neutrinos in the early Universe, and show that the future cosmic neutrino detection experiment PTOLEMY might be sensitive to neutrino signals that originate from DM annihilation in this model.

    hep-phastro-ph.COJCAP(2022)·15 citations
11. 11*

    Predictions of Ultra-High Energy Cosmic Ray Propagation in the Context of Homogeneously Modified Special Relativity

    Marco Danilo Claudio Torri🇮🇹 · Lorenzo Caccianiga🇮🇹 · Armando di Matteo🇮🇹 · Andrea Maino🇮🇹 · Lino Miramonti🇮🇹

    Ultra high energy cosmic rays (UHECRs) may interact with photon backgrounds and thus the universe is opaque to their propagation. Many Lorentz Invariance Violation (LIV) theories predict a dilation of the expected horizon from which UHECRs can arrive to Earth, in some case even making the interaction probability negligible. In this work, we investigate this effect in the context of the LIV theory that goes by the name of Homogeneously Modified Special Relativity (HMSR). In this work, making use of a specifically modified version of the Sim- Prop simulation program in order to account for the modifications introduced by the theory to the propagation of particles, the radius of the proton opacity horizon (GZK sphere), and the attenuation length for the photopion production process are simulated and the modifications of these quantities introduced by the theory are studied.

    hep-phhep-thSymmetry(2020)·10 citations
12. 12*

    Sterile neutrino dark matter, neutrino secret self-interactions, and extra radiation

    Manibrata Sen🇩🇪

    keV scale sterile neutrinos are excellent warm dark matter candidates. In the early Universe, these can be produced from oscillations and scatterings of active neutrinos. However, in the absence of any new physics, this mechanism is in severe tension with observations from X-ray searches. In this work, we show that secret self-interactions of active neutrinos, mediated by a scalar, can efficiently produce these sterile neutrinos without being ruled out by X-ray observations. These neutrino self-interactions are also testable: for a mediator mass greater than a few MeV, these self-interactions can give signatures in laboratory based experiments, while for lighter mediators, there will be observable consequences for upcoming cosmology probes.

    hep-phJ.Phys.Conf.Ser.(2021)·4 citations
13. 13*

    Higher-order QCD corrections to $H\to b\bar{b}$ from rational approximants

    Diogo Boito🇧🇷 · Cristiane Y. London🇧🇷 · Pere Masjuan🇪🇸

    We use rational approximants to study missing higher orders in the massless scalar-current quark correlator. We predict the yet unknown six-loop coefficient of its imaginary part, related to $\Gamma (H\to b\bar{b})$, to be $c_5=-6900\pm 1400$. With this result, the perturbative series becomes almost insensitive to renormalization scale variations and the intrinsic QCD truncation uncertainty is tiny. This confirms the expectation that higher-order loop computations for this quantity will not be required in the foreseeable future, as the uncertainty in $\Gamma (H\to b\bar{b})$ will remain largely dominated by the Standard Model parameters.

    hep-phJHEP(2022)·12 citations
14. 14*

    Seesaw lepton masses and muon $g-2$ from heavy vector-like leptons

    Hyun Min Lee🇰🇷 · Jiseon Song🇰🇷 · Kimiko Yamashita🇰🇷

    We propose a model for the vector-like lepton to explain the small muon mass by a seesaw mechanism, based on lepton-specific two Higgs doublet models with a local $U(1{)}^{\prime }$ symmetry. There is no bare muon mass for a nonzero $U(1{)}^{\prime }$ charge of the leptophilic Higgs doublet, so the physical muon mass is generated due to the mixing between the vector-like lepton and the muon after the leptophilic Higgs doublet and the dark Higgs get VEVs. In this scenario, the non-decoupling effects of the vector-like lepton give rise to leading contributions to the muon $g-2$, thanks to the light $Z^{\prime }$ and the light dark Higgs boson. We discuss various constraints on the model from lepton flavor violation, electroweak precision and Higgs data, as well as collider searches.

    hep-phJ.Korean Phys.Soc.(2021)·21 citations
15. 15*

    Charge asymmetry of new stable quarks in baryon asymmetrical Universe

    Arnab Chaudhuri🇷🇺 · Maxim Yu. Khlopov🇷🇺

    Effects of electroweak phase transition (EWPT) in balance between baryon excess and the excess of stable quarks of new generation is studied. With the conservation of SU(2) symmetry and other quantum numbers, it makes possible sphaleron transitions between baryons, leptons and new of leptons and quarks. A definite relationship between the excess relative to baryon asymmetry is established. In passing by we also show the small, yet negligible dilution in the pre-existing dark matter density due the sphaleron transition.

    hep-phastro-ph.CO0 citations
16. 16*

    Cosmological radiation density with non-standard neutrino-electron interactions

    Pablo Martínez-Miravé🇪🇸

    Non-standard interactions (NSI) between neutrinos and electrons can significantly modify the decoupling of neutrinos from the plasma. These interactions have two effects on the overall picture: (i) they alter neutrino oscillations though matter effects and (ii) they modify the scattering and annihilation processes involving neutrinos and electrons and positrons. We study the role of non-universal and flavour-changing NSI in the decoupling and how they impact the determination of the effective number of neutrinos, $N_{eff}$. We examine the degeneracies between NSI parameters and we compare the expected sensitivity from future cosmological surveys with the current limits from terrestrial experiments. We outline the complementarity between both approaches.

    hep-phastro-ph.COJ.Phys.Conf.Ser.(2021)·0 citations
17. 17*

    Pentagon Functions for One-Mass Planar Scattering Amplitudes

    Dmitry Chicherin🇫🇷 · Vasily Sotnikov🇩🇪 · Simone Zoia🇮🇹

    We present analytic results for all planar two-loop Feynman integrals contributing to five-particle scattering amplitudes with one external massive leg. We express the integrals in terms of a basis of algebraically-independent transcendental functions, which we call one-mass pentagon functions. We construct them by using the properties of iterated integrals with logarithmic kernels. The pentagon functions are manifestly free of unphysical branch cuts, do not require analytic continuation, and can be readily evaluated over the whole physical phase space of the massive particle production channel. We develop an efficient algorithm for their numerical evaluation and present a public implementation suitable for direct phenomenological applications.

    hep-phhep-thJHEP(2022)·117 citations
18. 18*

    Quantum tops at the LHC: from entanglement to Bell inequalities

    Claudio Severi🇬🇧 · Cristian Degli Esposti Boschi🇮🇹 · Fabio Maltoni🇧🇪 · Maximiliano Sioli🇮🇹

    We present the prospects of detecting quantum entanglement and the violation of Bell inequalities in $t\bar{t}$ events at the LHC. We introduce a unique set of observables suitable for both measurements, and then perform the corresponding analyses using simulated events in the dilepton final state, reconstructing up to the unfolded level. We find that entanglement can be established at better than 5$\sigma$ both at threshold as well as at high $p_T$ already in the LHC Run 2 dataset. On the other hand, only very high-$p_T$ events are sensitive to a violation of Bell inequalities, making it significantly harder to observe experimentally. By employing a sensitive and robust observable, two different unfolding methods and independent statistical approaches, we conclude that, at variance with previous estimates, testing Bell inequalities will be challenging even in the high luminosity LHC run.

    hep-phhep-exquant-phEPJC(2022)·168 citations
19. 19*

    Charming Penguins and Lepton Universality Violation in $b\to s{\ell }^{+}{\ell }^{-}$ decays

    Marco Ciuchini🇮🇹 · Marco Fedele🇩🇪 · Enrico Franco🇮🇹 · Ayan Paul🇩🇪 · Luca Silvestrini🇮🇹 · Mauro Valli🇺🇸

    The LHCb experiment has very recently presented new results on Lepton Universality Violation (LUV) in $B\to K^{(\ast )}{\ell }^{+}{\ell }^{-}$ decays involving $K_S$ in the final state, which strengthens the recent evidence of LUV obtained in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays and the previous measurements of $B\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$. While LUV observables in the Standard Model are theoretically clean, their predictions in New Physics scenarios are sensitive to the details of the hadronic dynamics, and in particular of the charming penguin contribution. In this work, we show how a conservative treatment of hadronic uncertainties is crucial not only to assess the significance of deviations from the Standard Model but also to obtain a conservative picture of the New Physics responsible for LUV. Adopting a very general parameterization of charming penguins, we find that: $i)$ current data hint at a sizable $q^2$ and helicity dependence of charm loop amplitudes; $ii)$ conservative NP solutions to $B$ anomalies favour a left-handed or an axial lepton coupling rather than a vector one.

    hep-phhep-exEPJC(2023)·74 citations
20. 20*

    Constraining CP-violation in the Higgs-top-quark interaction using machine-learning-based inference

    Henning Bahl🇺🇸 · Simon Brass🇩🇪

    While CP violation in the Higgs interactions with massive vector boson is already tightly constrained, the CP nature of the Higgs interactions with fermions is far less constrained. In this work, we assess the potential of machine-learning-based inference methods to constrain CP violation in the Higgs top-Yukawa coupling. This approach enables the use of the full available kinematic information. Concentrating on top-associated Higgs production with the Higgs decaying to two photons, we derive expected exclusion bounds for the LHC and the high-luminosity phase of the LHC. We also study the dependence of these bounds on the Higgs interaction with massive vector bosons and their robustness against theoretical uncertainties. In addition to deriving expected exclusion bounds, we discuss at which level a non-zero CP-violating top-Yukawa coupling can be distinguished from the SM. Moreover, we analyze which kinematic distributions are most sensitive to a CP-violating top-Yukawa coupling.

    hep-phJHEP(2022)·43 citations
21. 21*

    One-loop unquenched three-gluon and ghost-gluon vertex in the Curci-Ferrari model

    Felipe Figueroa🇫🇷 · Marcela Peláez🇺🇾

    In this article we study the unquenched three-gluon and ghost-gluon vertex in all momentum range going from the ultraviolet to the infrared regime using the Curci-Ferrari model at one-loop in Landau gauge as an extension of the results presented in \cite{Pelaez:2013cpa}. Results are compared with recent lattice data for $SU(3)$ in the unquenched case. This calculation is a pure prediction of the model because it does not require fixing any parameter once two-point functions are fitted. An analysis of the influence of dynamical quarks in the position of the zero crossing of the three-gluon vertex is presented. Due to the recent improvements in infrared lattice data for the quenched three-gluon correlation function \cite{Aguilar:2021lke} we also redo the comparison between our one-loop results in this limit and the lattice obtaining a very good match.

    ↳ hep-thhep-lathep-phPRD(2022)·15 citations
22. 22*

    The $H_0$ and $S_8$ tensions necessitate early and late time changes to $\Lambda$CDM

    Steven J. Clark🇺🇸 · Kyriakos Vattis🇺🇸 · JiJi Fan🇺🇸 · Savvas M. Koushiappas🇺🇸

    An only early or only late time alteration to $\Lambda$CDM has been inadequate at resolving both the $H_0$ and $S_8$ tensions simultaneously; however, a combination of early and late time alterations to $\Lambda$CDM can provide a solution to both tensions. As an illustration, we examine a combined Early Dark Energy - Decaying Dark Matter model. While early dark energy has the ability to resolve the $H_0$ tension, it leads to a discrepancy in $S_8$ measurements. We show that the addition of decaying dark matter helps resolve the $S_8$ discrepancy that would otherwise be enhanced in an early dark energy model, while the latter is able to relieve the $H_0$ disagreement to within the 95th percentile interval. Our results show a preference for the combined model over $\Lambda$CDM with $\Delta \mathrm{AIC}=-6.72$, hinting that both early and late universe modifications may be necessary to address the cosmological tensions.

    ↳ astro-ph.COhep-phPRD(2023)·82 citations
23. 23*

    Localization properties of Dirac modes at the Roberge-Weiss phase transition

    Marco Cardinali🇮🇹 · Massimo D'Elia🇮🇹 · Francesco Garosi🇮🇹 · Matteo Giordano🇭🇺

    We study the localization properties of the low-lying Dirac eigenmodes in QCD at imaginary chemical potential ${\hat{\mu }}_I=\pi$ at temperatures above the Roberge-Weiss transition temperature $T_{\mathrm{RW}}$. We find that modes are localized up to a temperature-dependent "mobility edge" and delocalized above it, and that the mobility edge extrapolates to zero at a temperature compatible with $T_{\mathrm{RW}}$. This supports the existence of a strong connection between localization of the low Dirac modes and deconfinement, studied here for the first time in a model with a genuine deconfinement transition in the continuum limit in the presence of dynamical fermions.

    ↳ hep-lathep-phhep-thPRD(2022)·18 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.