Mon·Aug 2, 2021Monday·August 2, 2021

1. 01*

   Clean energy from dark matter?

   Pierre Sikivie🇺🇸

   A contribution to Frank Wilczek's 70th birthday's festschrift, this brief note considers how much power can be extracted from dark matter.

   hep-phastro-ph.GAphysics.app-ph4 citations
2. 02*

   A dark matter WIMP that can be detected and definitively identified with currently planned experiments

   Caden LaFontaine🇺🇸 · Bailey Tallman🇺🇸 · Spencer Ellis🇺🇸 · Trevor Croteau🇺🇸 · Brandon Torres🇺🇸 · Sabrina Hernandez🇺🇸 · Diego Cristancho Guerrero🇺🇸 · Jessica Jaksik🇺🇸 · Drue Lubanski🇺🇸 · Roland E. Allen🇺🇸

   A recently proposed dark matter WIMP has only second-order couplings to gauge bosons and itself. As a result, it has small annihilation, scattering, and creation cross-sections, and is consequently consistent with all current experiments and the observed abundance of dark matter. These cross-sections are, however, still sufficiently large to enable detection in experiments that are planned for the near future, and definitive identification in experiments proposed on a longer time scale. The (multi-channel) cross-section for annihilation is consistent with thermal production and freeze-out in the early universe, and with current evidence for dark matter annihilation in analyses of the observations of gamma rays by Fermi-LAT and antiprotons by AMS-02, as well as the constraints from Planck and Fermi-LAT. The cross-section for direct detection via collision with xenon nuclei is estimated to be slightly below $10^{-47}$ cm${}^2$, which should be attainable by LZ and Xenon nT and well within the reach of Darwin. The cross-section for collider detection via vector boson fusion is estimated to be $\sim 1$ fb, and may be ultimately attainable by the high-luminosity LHC; definitive collider identification will probably require the more powerful facilities now being proposed.

   hep-phUniverse(2021)·7 citations
3. 03*

   Where are $3P$ and higher $P-$wave states in the charmonium family?

   Ming-Xiao Duan🇨🇳 · Xiang Liu🇨🇳

   How to hunt for higher $P$-wave states of charmonium is still an open topic when $2P$ charmonia were identified. {In this work, we present an unquenched quark model calculation to illustrate the spectroscopy behavior of these $3P$, $4P$ and $5P$ states in charmonium family.} For the $3P$ charmonia, the predicted masses are around 4.2 GeV and their two-body open-charm decay behaviors were given, by which we propose that searching for these $3P$ states via their open-charm decay channels from $\gamma \gamma$ fusion and $B$ decay can be accessible at future experiment like LHCb and Belle II. We continue to calculate the masses of these $4P$ and $5P$ charmonia. Combing with these calculated results of higher $P$-wave states of charmonium, we find that the coupled-channel effect becomes more obvious with increasing the radial quantum number, which can be understood well by the modified Godfrey-Isgur model with screened potential.

   hep-phhep-exPRD(2021)·26 citations
4. 04*

   Further study of $f_0(1710)$ with coupled-channel approach and hadron molecular picture

   Zheng-Li Wang🇨🇳 · Bing-Song Zou🇨🇳

   The $f_0(1710)$ was previously proposed to be dynamically generated state by interactions between vector mesons. We extend the study of $f_0(1710)$ by including its coupling to channels of pseudoscalar mesons within coupled-channel approach. The channels involved are $K^{\ast }{\bar{K}}^{\ast },\rho \rho ,\omega \omega ,\varphi \varphi ,\omega \varphi ,\pi \pi ,K\bar{K},\eta \eta$. We show that the pole assigned to $f_0(1710)$ does not change much. Then we calculate the partial decay widths of $f_0(1710)\to K^{\ast }{\bar{K}}^{\ast }\to \pi \pi ,K\bar{K},\eta \eta$ as the coupled channel dynamically generated state as well as assuming it to be pure $K^{\ast }{\bar{K}}^{\ast }$ molecule. In both cases the ratios of partial decay widths agree fairly with that in PDG.

   hep-phPRD(2021)·20 citations
5. 05*

   Central exclusive production of ${\eta }_c$ and ${\chi }_{c0}$ in the light-front k${}_{\perp }$-factorization approach

   Izabela Babiarz🇵🇱 · Roman Pasechnik🇸🇪 · Wolfgang Schäfer🇵🇱 · Antoni Szczurek🇵🇱

   We study the exclusive production of $J^{PC}=0^{++},0^{--}$ charmonium states in proton-proton collisions at the LHC energies The $pp\to pp{\eta }_c$ reaction is discussed for the first time. We observe a substantial contribution from the nonperturbative domain of gluon virtualities, especially for ${\eta }_c$ production. To model the nonperturbative region better, we utilize models of the unintegrated gluon distribution based on parametrizations of the color dipole cross-section.

   hep-phSciPost Phys.Proc.(2022)·2 citations
6. 06*

   Diffractive dissociation in future electron-ion colliders

   Anh Dung Le🇫🇷

   We study diffractive scattering cross sections, focusing on the rapidity gap distribution in realistic kinematics at future electron-ion colliders. Our study consists in numerical solutions of the QCD evolution equations in both fixed and running coupling frameworks. The fixed and the running coupling equations are shown to lead to different shapes for the rapidity gap distribution. The obtained distribution when the coupling is fixed exhibits a shape characteristic of a recently developed model for diffractive dissociation, which indicates the relevance of the study of that diffractive observable for the partonic-level understanding of diffraction.

   hep-phSciPost Phys.Proc.(2022)·0 citations
7. 07*

   Constraining the nuclear gluon PDF with inclusive hadron production data

   P. Duwentäster🇩🇪 · L. A. Husová🇩🇪 · T. Ježo🇩🇪 · M. Klasen🇩🇪 · K. Kovařík🇩🇪 · A. Kusina🇵🇱 · K. F. Muzakka🇩🇪 · F. I. Olness🇺🇸 · I. Schienbein🇫🇷 · J.Y. Yu🇺🇸

   The nuclear parton distribution functions (nPDFs) of gluons are known to be difficult to determine with fits of deep inelastic scattering (DIS) and Drell-Yan (DY) data alone. Therefore, the nCTEQ15 analysis of nuclear PDFs added inclusive neutral pion production data from RHIC to help in constraining the gluon. In this analysis, we present a new global analysis of nuclear PDFs based on a much larger set of single inclusive light hadron data from RHIC and the LHC. Using our new nCTEQ code (nCTEQ++) with an optimized version of INCNLO we study systematically the limitations of the theory and the impact of the fragmentation function uncertainty.

   hep-phnucl-thSciPost Phys.Proc.(2022)·1 citation
8. 08*

   $U(1{)}_{L_{\mu }-L_{\tau }}$ for Light Dark Matter, $g_{\mu }-2$, the $511$ keV excess and the Hubble Tension

   Manuel Drees🇩🇪 · Wenbin Zhao🇩🇪

   In this paper we introduce a light Dirac particle $\psi$ as thermal dark matter candidate in a $U(1{)}_{L_{\mu }-L_{\tau }}$ model. Together with the new gauge boson $X$, we find a possible parameter space with $m_X\simeq 20$ MeV, $U(1{)}_{L_{\mu }-L_{\tau }}$ coupling $g_X\simeq 5\cdot 10^{-4}$ and $m_{\psi }\gtrsim m_X/2$ where the $(g-2{)}_{\mu }$ anomaly, dark matter, the Hubble tension, and (part of) the excess of $511$ keV photons from the region near the galactic center can be explained simultaneously. This model is safe from current experimental and astrophysical constraints, but can be probed by the next generation of neutrino experiments as well as low-energy $e^{+}{e}^{-}$ colliders.

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

   Massive Gravitons as Feebly Interacting Dark Matter Candidates

   Haiying Cai🇰🇷 · Giacomo Cacciapaglia🇫🇷 · Seung J. Lee🇰🇷

   We detailed our discovery of a chiral enhancement in the production cross sections of massive spin-2 gravitons, below the electroweak symmetry breaking scale, that makes them ideal dark matter candidates for the freeze-in mechanism. The result is independent of the physics at high scales, and points toward masses in the keV- MeV range. The graviton is, therefore, a sub-MeV dark matter particle, as favored by the small scale galaxy structures. We apply the novel calculation to a Randall-Sundrum model with multiple branes, showing a significant parameter space where the first two massive gravitons saturate the dark matter relic density.

   hep-phPRL(2022)·25 citations
10. 10*

    T-odd quark-gluon-quark correlation function in the light-front quark-diquark model

    Shubham Sharma🇮🇳 · Narinder Kumar🇮🇳 · Harleen Dahiya🇮🇳

    We have scrutinized the transverse momentum dependent quark-gluon-quark correlation function. We have utilized the light-front quark-diquark model to study the time-reversal-odd interaction-dependent twist-3 gluon distributions which we have obtained from the disintegration of the transverse momentum dependent quark-gluon-quark correlator. Specifically, we have studied the behavior of ${\tilde{e}}_L$ and ${\tilde{e}}_T$ while considering our diquark to be an axial-vector.

    hep-phSciPost Phys.Proc.(2022)·0 citations
11. 11*

    Three-photon productions within the $k_t$-factorization for the ATLAS-LHC data

    R. Kord Valeshabadi🇮🇷 · M. Modarres🇮🇷 · S. Rezaie🇮🇷

    Recently, the ATLAS data of isolated three-photon production showed that the next-to-leading order (NLO) collinear factorization is not enough to describe experimental data. Therefore, one needs to calculate the cross section beyond the NLO, and as showed later, these data can be well described by the NNLO calculation within the collinear factorization framework. However, it is shown that the $k_t$-factorization can be quite successful in describing exclusive and high energy collision processes, henceforth we decided to calculate isolated three-photon production within this framework. In this work we use the Martin, Ryskin, and Watt unintegrated parton distribution functions (MRW UPDFs) at LO and NLO levels, in addition to parton branching (PB) UPDFs in order to calculate cross section which we utilize the KATIE parton level event generator. It will be shown that in contrast to collinear factorization, the $k_t$-factorization can describe quiet well the three-photon production ATLAS data. Interestingly our results using the NLO-MRW and PB UPDFs can cover the data within their uncertainty bands, similar to the NNLO collinear results.

    hep-phhep-exhep-thEPJC(2021)·10 citations
12. 12*

    The P-P(P̄) cross-section of isolated single-photon production in the $k_t$-factorization and different angular ordering unintegrated parton distributions frameworks

    R. Aminzadeh Nik🇮🇷 · M. Modarres🇮🇷 · N. Olanj🇮🇷 · R. Taghavi🇮🇷

    In the present work, it is intended to calculate and study the single and double differential cross-sections of the prompt single-photon production as a function of produced single-photon transverse momentum and rapidity, in the high-energy P-P(P̄) colliders, such as LHC and TEVATRON. The differential cross-sections of prompt single-photon production are calculated in the $k_t$-factorization frameworks using various angular ordering unintegrated parton distribution functions (UPDF), namely the Kimber et al. and Martin et al. procedures. These scheme-dependent UPDF are generated in the leading and next-to-leading order levels to predict and analyze the different partonic contributions to the above cross-sections. The above two procedures utilize the phenomenological parton distribution functions (PDF) libraries of Martin et al., i.e., MMHT2014. It is shown that the calculated prompt single-photon production differential cross-sections in the above frameworks are relatively successful in generating satisfactory results compared to the experimental data of different collaborations, i.e., CDF (2017), ATLAS (2017), CMS (2011) and D0 (2006), as well as the other theoretical predictions such as collinear factorization Monte Carlo calculations (the JETPHOX, SHERPA, PYTHIA, and MCFM methods). Also, for a closer precision, the differential cross-section for the NLO gluon-gluon , quark-gluon and quark-(anti)quark processes are calculated. An extensive discussion and comparison are made regarding (i) the behavior of the contributing partonic sub-processes, (ii) the possible double-counting between the $2\to 2$ and $2\to 3$ sub-processes, i.e., gluons-fusion, in our calculated prompt single-photon production differential cross-sections and (iii) the sensibility check of our results to the different angular ordering constraints.

    hep-phhep-exhep-thPRD(2021)·5 citations
13. 13*

    Inclusive jet and dijet productions using $k_t$ and $(z,k_t)\text{-factorizations}$ versus ZEUS collaboration data

    R. Kord Valeshabadi🇮🇷 · M. Modarres🇮🇷 · S. Rezaie🇮🇷 · R. Aminzadeh Nik🇮🇷

    In this paper, we investigate the differential cross sections of the inclusive jet and dijet productions of the ZEUS collaboration data at the center of mass energies of $\sim 300GeV$ and $319GeV$ using the $k_t$ and $(z,k_t)\text{-factorizations}$ with the different unintegrated and double unintegrated parton distribution functions, i.e., UPDFs and DUPDFs, respectively. The \textsc{KaTie} event generator is used to calculate the differential cross section with the UPDFs, while for the input DUPDFs the calculations are directly performed by evaluating the corresponding matrix elements. We check the effect of choosing the different implementation of angular or strong ordering constraints using the UPDFs and the corresponding DUPDFs of Kimber-Martin-Ryskin (KMR) and the leading-order (LO) and next-to-leading-order (NLO) Martin-Ryskin-Watt (MRW) approaches. The impacts of choosing virtualities $k^2=k_t^2$ or $k^2=\frac{k_t^2}{(1-z)}$ in the differential cross section predictions for the ZEUS experimental data are also investigated. It is observed that, as one should expect, the applications of $(z,k_t)\text{-factorization}$ is better than the $k_t\text{-factorization}$ framework for the predictions of high virtuality $Q^2$ with respect to the ZEUS collaboration data, and also the results of the KMR and LO-MRW UPDFs and DUPDFs are reasonably close to each other and in general can describe the data. It is also observed that only in the case of $k_t$-factorization, the inclusion of Born level makes our results to overshoot the inclusive jet experimental data.

    hep-phhep-exhep-thJ.Phys.G(2021)·8 citations
14. 14*

    A validity check of the KATIE parton level event generator in the $k_t$-factorization and collinear frameworks

    R. Kord Valeshabadi🇮🇷 · M. Modarres🇮🇷 · S. Rezaie🇮🇷

    In the present paper, we check and study the validity of the \textsc{KaTie} parton level event generator, by calculating the inclusive electron-proton (ep) dijet and the Proton-proton (p-p) Drell-Yan electron-pair productions differential cross sections in the $k_t$- and collinear factorization frameworks. The Martin-Ryskin-Watt (MRW) unintegrated parton distribution functions (UPDFs) are used as the input UPDFs. The results are compared with those of ZEUS ep inclusive dijet and ATLAS p-p Drell-Yan electron-pair productions, experimental data. The \textsc{KaTie} parton level event generator can directly calculate the cross sections in the $k_t$-factorization framework. It is noticed that the lab to the Breit transformation in this generator is not correctly implemented by its author, so the produced output does not cover the ep ZEUS experimental data in which the mentioned transformation is applied. By fixing the above transformation in the \textsc{KaTie} generator code, we could appropriately produce the ep inclusive dijet differential cross section, in comparison with those of ZEUS data. It is also shown that the MRW at the NLO level, with the angular ordering constraint can successfully predict the ATLAS p-p Drell-Yan data. Finally, as it is expected, we conclude that the $k_t$-factorization is an appropriate tool for the small longitudinal parton momenta and high center of mass energies, with respect to the collinear one.

    hep-phhep-exhep-thPRD(2021)·6 citations
15. 15*

    The analysis of Drell-Yan lepton pair production in the P-P(P̄) colliders using different angular ordering constraints and $k_t$-factorization approach

    M. Modarres🇮🇷 · R. Taghavi🇮🇷 · R. Aminzadeh Nik🇮🇷 · R. Kord Valeshabadi🇮🇷

    In this work, the P-P(P̄) Drell-Yan lepton pair production (DY) differential cross sections at hadrons colliders, such as LHC and TEVATRON, are studied in the $k_t$-factorization framework. In order to take into account the transverse momenta of incoming partons, we use the unintegrated parton distribution functions (UPDF) of Kimber et al (KMR) and Martin et al (MRW) in the leading order (LO) and next-to-leading-order (NLO) levels with the input MMHT2014 PDF libraries. Based on the different off-shell partonic matrix elements, we analyze the behaviors of DY differential cross sections with respect to the invariant mass, the transverse momentum and the rapidity as well as the specific angular correlation between the produced leptons. The numerical results are compared with the experimental data, in different energies, which are reported by various collaborations, such as CDF, CMS, ATLAS and LHCb. It is shown that the NLO-MRW and KMR schemes predict closer results to the data compared to the LO-MRW, since we do not have fragmentation.

    hep-phhep-exhep-thPRD(2021)·8 citations
16. 16*

    Constraints from the CHARM experiment on Heavy Neutral Leptons with tau mixing

    Iryna Boiarska🇩🇰 · Alexey Boyarsky🇳🇱 · Oleksii Mikulenko🇳🇱 · Maksym Ovchynnikov🇳🇱

    We re-analyze the results of the searches for Heavy Neutral Leptons (HNLs) by the CHARM experiment. We study HNL decay channel $N\to e^{+}{e}^{-}\nu /{\mu }^{+}{\mu }^{-}\nu$ and show that, in addition to the constraints on the HNL's mixings with ${\nu }_e$ or ${\nu }_{\mu }$, the same data also implies limits on the HNLs that mix only with ${\nu }_{\tau }$ and have masses in the range $380\text{ MeV}<m_N\lesssim 1.6\text{ GeV}$ - the region in the parameter space that was considered in the literature as a target for HNLs searches.

    hep-phPRD(2021)·74 citations
17. 17*

    Update on $|V_{us}|$ and $|V_{us}/V_{ud}|$ from semileptonic kaon and pion decays

    Chien-Yeah Seng🇩🇪 · Daniel Galviz🇩🇪 · William J. Marciano🇺🇸 · Ulf-G. Meißner🇩🇪

    We discuss the recent progress in the study of semileptonic kaon and pion decays, including new experimental results, improved electroweak radiative corrections, form factor calculations and isospin-breaking effects. As a result, we obtain $|V_{us}|=0.22309(40)(39)(3)$ from kaon semileptonic decays and $|V_{us}/V_{ud}|=0.22908(66)(41)(40)(2)(1)$ from the ratio between the kaon and pion semileptonic decay rates. We report an apparent violation of the top-row Cabibbo-Kobayashi-Maskawa matrix unitarity at a $3.2\sim 5.6\sigma$ level, and a discrepancy at a $2.2\sigma$ level between the value of $|V_{us}/V_{ud}|$ determined from the vector and axial charged weak interactions. Prospects for future improvements in those comparative precision tests involving $|V_{ud}|$, $|V_{us}|$ and their implications for physics beyond the Standard Model are described.

    hep-phhep-exhep-latnucl-ex+1PRD(2022)·67 citations
18. 18*

    Low-scale minimal linear seesaw model for neutrino mass and flavor mixing

    Ernesto A. Matute🇨🇱

    We consider an extension of the Standard Model with three right-handed (RH) neutrinos and a Dirac pair of extra sterile neutrinos, odd under a discrete $Z_2$ symmetry, in order to have left-right symmetry in the neutrino content and obtain tiny neutrino masses from the latter ones only. Our working hypothesis is that the heavy RH neutrinos do not influence phenomenology at low energies. We use the usual high-scale seesaw to suppress all of the mass terms involving RH neutrinos and a low-scale minimal variant of the linear seesaw led by the Dirac mass of the extra sterile neutrinos to provide the small mass of active neutrinos. One of the active neutrinos is massless, which fixes the mass of the other two on the basis of a soft breaking of the $Z_2$ symmetry. The mixing between the extra neutrinos makes for a particle that effectively behaves like a Dirac sterile neutrino with mass around the GeV level.

    hep-phMod.Phys.Lett.A(2021)·3 citations
19. 19*

    Two-loop leading-colour QCD helicity amplitudes for Higgs boson production in association with a bottom-quark pair at the LHC

    Simon Badger🇮🇹 · Heribertus Bayu Hartanto🇬🇧 · Jakub Kryś🇮🇹 · Simone Zoia🇮🇹

    We compute the two-loop QCD helicity amplitudes for the production of a Higgs boson in association with a bottom-quark pair at a hadron collider. We take the approximations of leading colour and work in the five flavour scheme, where the bottom quarks are massless while the Yukawa coupling is non-zero. We extract analytic expressions from multiple numerical evaluations over finite fields and present the results in terms of an independent set of special functions that can be reliably evaluated over the full phase space.

    hep-phhep-thJHEP(2021)·81 citations
20. 20*

    $\eta /s-\hat{q}/T^3$ Relation at Next-to-Leading Order in QCD

    Berndt Müller🇺🇸

    The relation between the specific shear viscosity $\eta /s$ and the dimensionless jet quenching parameter $\hat{q}/T^3$ in perturbative QCD is explored at next-to-leading order in the coupling constant. It is shown that the relation changes little, although both transport coefficients independently are subject to large modifications at the NLO level. This finding confirms that the relationship is robust.

    hep-phnucl-thPRD(2021)·16 citations
21. 21*

    Probing the long-range structure of the $T_{cc}^{+}$ with the strong and electromagnetic decays

    Lu Meng🇩🇪 · Guang-Juan Wang🇯🇵 · Bo Wang🇨🇳 · Shi-Lin Zhu🇨🇳

    Very recently, the LHCb Collaboration reported the doubly charmed tetraquark state $T_{cc}^{+}$ below the $D^{\ast +}{D}^0$ threshold about $273$ keV. As a very near-threshold state, its long-distance structure is very important. In the molecular scheme, we relate the coupling constants of $T_{cc}^{+}$ with $D^{\ast 0}{D}^{+}$ and $D^{\ast +}{D}^0$ to its binding energy and mixing angle of two components with a coupled-channel effective field theory. With the coupling constants, we investigate the kinetically allowed strong decays $T_{cc}^{+}\to D^0{D}^0{\pi }^{+}$, $T_{cc}^{+}\to D^{+}{D}^0{\pi }^0$ and radiative decays $D^{+}{D}^0\gamma$. Our results show that the decay width of $T_{cc}^{+}\to D^0{D}^0{\pi }^{+}$ is the largest one, which is just the experimental observation channel. Our theoretical total strong and radiative widths are in favor of the $T_{cc}^{+}$ as a $|D^{\ast +}{D}^0⟩$ dominated bound state. The total strong and radiative width in the single channel limit and isospin singlet limit are given as $59.7_{-4.4}^{+4.6}\text{ keV}$ and $46.7_{-2.9}^{+2.7}\text{ keV}$, respectively. Our calculation is cutoff-independent and without prior isospin assignment. The absolute partial widths and ratios of the different decay channels can be used to test the structure of $T_{cc}^{+}$ state when the updated experimental results are available.

    hep-phhep-exPRD(2021)·117 citations
22. 22*

    General Freeze-in and Freeze-out

    Michele Redi🇮🇹 · Andrea Tesi🇮🇹

    We use the framework of relativistic and non-relativistic conformal field theories (CFT) to derive general results relevant for the production of weakly coupled and strongly coupled dark sectors through thermal interactions. Our result reproduce trivially known formulas for $2\to n$ processes and extend to general $m\to n$ processes as well as interacting dark sectors. As concrete examples we consider freeze-in of a relativistic CFT coupled to the SM with contact interactions and derive Sommerfeld enhancement of non-relativistic cross-sections from the theory of fermions at unitarity.

    hep-phhep-thJHEP(2021)·13 citations
23. 23*

    Perturbative unitarity constraints on generic Yukawa interactions

    Lukas Allwicher🇨🇭 · Pere Arnan🇮🇹 · Daniele Barducci🇮🇹 · Marco Nardecchia🇮🇹

    We study perturbative unitarity constraints on generic Yukawa interactions where the involved fields have arbitrary quantum numbers under an ${\prod }_{i}SU(N_i)\otimes U(1)$ group. We derive compact expressions for the bounds on the Yukawa couplings for the cases where the fields transform under the trivial, fundamental or adjoint representation of the various $SU(N)$ factors. We apply our results to specific models formulated to explain the anomalous measurements of $(g-2{)}_{\mu }$ and of the charged- and neutral-current decays of the $B$ mesons. We show that, while these models can generally still explain the observed experimental values, the required Yukawa couplings are pushed at the edge of the perturbative regime.

    hep-phhep-thJHEP(2021)·70 citations
24. 24*

    Two-loop Electroweak Corrections to the Top-Quark Contribution to ${ϵ}_K$

    Joachim Brod🇺🇸 · Sandra Kvedaraitė🇺🇸 · Zachary Polonsky🇺🇸

    The parameter ${ϵ}_K$ measures $CP$ violation in the neutral kaon system. It is a sensitive probe of new physics and plays a prominent role in the global fit of the Cabibbo-Kobabyashi-Maskawa matrix. The perturbative theory uncertainty is currently dominated by the top-quark contribution. Here, we present the calculation of the full two-loop electroweak corrections to the top-quark contribution to ${ϵ}_K$, including the resummation of QED-QCD logarithms. We discuss different renormalization prescriptions for the electroweak input parameters. In the traditional normalization of the weak Hamiltonian with two powers of the Fermi constant $G_F$, the top-quark contribution is shifted by $-1\%$.

    hep-phJHEP(2021)·25 citations
25. 25*

    Imprint of Early Dark Energy in Stochastic Gravitational Wave Background

    Chia-Feng Chang🇺🇸

    Early dark energy that relieves Hubble tension leaves a fingerprint in the primordial stochastic gravitational wave (GW) background that originates from cosmic string network. The signal is not only detectable with future planned GW experiments, but also distinguishable from other astrophysical and cosmological signals in the GW frequency spectrum. We find that the cosmic string GW spectrum can probe other new physics that influence the universe in post-Big-Bang-Nucleosynthesis with mid-band GW detection, which extends GW cosmic archaeology search region.

    ↳ astro-ph.COgr-qchep-phPRD(2022)·7 citations
26. 26*

    Search for neutrino non-standard interactions with ANTARES and KM3NeT-ORCA

    J. J. Hernández Rey🇪🇸 · N. R. Khan Chowdhury🇪🇸 · J. Manczak🇪🇸 · S. Navas🇪🇸 · J. D. Zornoza (on behalf of the ANTARES and KM3NeT collaborations)🇪🇸

    Non-standard interactions (NSIs) in the propagation of neutrinos in matter can lead to significant deviations in neutrino oscillations expected within the standard 3-neutrino framework. These additional interactions would result in an anomalous flux of neutrinos observable at neutrino telescopes. The ANTARES detector and its next-generation successor, KM3NeT, located in the abyss of the Mediterranean Sea, have the potential to measure sub-dominant effects in neutrino oscillations, coming from non-standard neutrino interactions. In this contribution, a likelihood-based search for NSIs with 10 years of atmospheric muon-neutrino data recorded with ANTARES is reported and sensitivity projections for KM3NeT/ORCA, based on realistic detector simulations, are shown. The bounds obtained with ANTARES in the NSI $\mu -\tau$ sector constitute the most stringent limits up to date.

    ↳ hep-exhep-phJINST(2021)·11 citations
27. 27*

    Theoretical interpretation of the observed neutrino emission from Tidal Disruption Events

    Walter Winter🇩🇪 · Cecilia Lunardini🇺🇸

    The observation of a neutrino at IceCube in association with the Tidal Disruption Event (TDE) AT2019dsg has suggested TDEs as a new class of sources of astrophysical neutrinos. We present a model of this multi-messenger observation in a jetted concordance scenario, where the neutrino production is directly linked to the observed X-rays, and the timing of the neutrino observation (about 150 days post peak) can be naturally described. We briefly discuss the implications of our model for future neutrino-TDE associations.

    ↳ astro-ph.HEhep-phPoS(2021)·5 citations
28. 28*

    How does the shape of gamma-ray bursts' pulses affect the duration distribution?

    Mariusz Tarnopolski🇵🇱

    Gamma-ray bursts (GRBs) come in two types, short and long. The distribution of logarithmic durations of long GRBs is asymmetric rather than Gaussian. Such an asymmetry, when modelled with a mixture of Gaussian distributions, requires an introduction of an additional component, often associated with another class of GRBs. However, when modelled with inherently asymmetric distributions, there is no need for such a component. The cosmological dilation was already ruled out as a source of the asymmetry, hence its origin resides in the progenitors. GRB light curves (LCs) are usually well described by a series of fast-rise-exponential-decay pulses. A statistical analysis of ensembles of simulated LCs shows that the asymmetry is a natural consequence of the pulse shape and the multi-pulse character of the LCs.

    ↳ astro-ph.HEastro-ph.COhep-phphysics.space-phMNRAS(2021)·3 citations
29. 29*

    Chiral condensates for neutron stars in hadron-quark crossover: from a parity doublet nucleon model to an NJL quark model

    Takuya Minamikawa🇯🇵 · Toru Kojo🇨🇳 · Masayasu Harada🇯🇵

    We study the chiral condensates in neutron star matter from nuclear to quark matter domain. We describe nuclear matter with a parity doublet model (PDM), quark matter with the Nambu--Jona-Lasino (NJL) model, and a matter at the intermediate density by interpolating nuclear and quark matter equations of state. The model parameters are constrained by nuclear physics and neutron star observations. Various condensates in the interpolated domain are estimated from the chemical potential dependence of the condensates at the boundaries of the interpolation. The use of the PDM with substantial chiral invariant mass ($m_0\gtrsim 500$ MeV, which is favored by the neutron star observations) predicts the mild chiral restoration, and the significant chiral condensate remains to baryon density $n_B\sim 2-3n_0$ ($n_0\simeq 0.16{\mathrm{fm}}^{-3}$: nuclear saturation density), smoothly approaching the NJL predictions for the color-flavor-locked phase at $n_B\gtrsim 5n_0$. The same method is applied to estimate diquark condensates, number densities of up-, down- and strange-quarks, and the lepton fraction. In our descriptions the chiral restoration in the interpolated domain proceeds with two conceptually distinct chiral restoration effects; the first is associated with the positive scalar density in a nucleon, relevant in dilute regime, and the other primarily arises from the modification of the quark Dirac sea, which is triggered by the growth of the quark Fermi sea. We discuss several qualitative conjectures to interpolate the microphysics in nuclear and quark matter.

    ↳ nucl-thastro-ph.HEhep-phPRC(2021)·32 citations
30. 30*

    Revisiting the AMS-02 antiproton excess: The role of correlated errors

    Jan Heisig🇧🇪 · Michael Korsmeier🇸🇪 · Martin Wolfgang Winkler🇸🇪

    Cosmic-ray antiprotons are a remarkable diagnostic tool for the study of astroparticle physics' processes in our Galaxy. While the bulk of measured antiprotons is consistent with a secondary origin, several studies have found evidence for a subdominant primary component in the AMS-02 data. In this proceedings article, we revisit the excess considering systematic errors that could affect the signal. Of particular importance are unknown correlations in the AMS-02 systematic errors, the dominant of which are associated with the cross sections for cosmic-ray absorption in the detector. We compute their correlations in a careful reevaluation of nuclear scattering data, utilizing the Glauber-Gribov theory to introduce a welcomed redundancy that we explore in a global fit. The inclusion of correlated errors has a dramatic effect on the significance of the signal. In particular, the analysis becomes more sensitive to the diffusion model at low rigidities. For a minimal extension beyond single-power-law diffusion, the global significance drops below 1$\sigma$ severely questioning the robustness of the finding.

    ↳ astro-ph.HEhep-phPoS(2021)·3 citations
31. 31*

    DIS2021 Workshop Proceedings: Backward-Angle (u-Channel) Meson Production from JLab 12 GeV Hall C to EIC

    W. B. Li🇺🇸

    The recent exclusive backward-angle electroproduction of omega from Jefferson Lab Hall C electron-proton fixed-target scattering experiments above the resonance region hints at a new domain of applicability of QCD factorization in a unique u-channel kinematics regime. Thanks to this effort, the interest in studying nucleon structure through u-channel meson production observables has grown significantly. In the fixed target configuration, the u-channel meson electroproduction observables feature a unique interaction picture: the target proton absorbs nearly all momentum induced by virtual photons and recoils forward, while the produced mesons (such as omega or pions) are left behind almost at rest near the target station. In this presentation, We provide a summary of the key observations of the existing u-channel meson production results, update-to-date theory insights, and a path to further exploration from JLab 12 GeV Hall C program to the future Electron-Ion Colliders.

    ↳ nucl-exhep-phnucl-thSciPost Phys.Proc.(2022)·1 citation
32. 32*

    Fast flavor conversion of neutrinos in presence of matter bulk velocity

    Ian Padilla-Gay🇩🇰 · Shashank Shalgar🇩🇰

    A dense gas of neutrinos and antineutrinos can undergo fast pairwise conversions near the decoupling regions of core-collapse supernovae and in compact binary neutron star mergers. The flavor dependent neutrino heating can play a role in sustaining convection inside the hot and dense matter. In this paper, we study the unexplored effect of the bulk velocity of matter on fast pairwise conversions and demonstrate that depending on the direction and the magnitude of the bulk velocity, neutrino flavor conversions could be significantly enhanced or suppressed. The bulk velocity of matter, which is usually neglected in the context of neutrino oscillations, can reach values of one-tenth of the speed of light in astrophysical environments. We find that bulk velocities much smaller than the maximum allowed velocities can substantially change the neutrino flavor conversion rate. The demonstration of possible enhancement of neutrino flavor conversion rate due to the bulk velocity of matter also raises several important issues that are of relevance in the supernova mechanism. Future studies with realistic velocity profiles could elucidate the possible implications on the phenomenology of core-collapse supernovae and neutron star mergers.

    ↳ astro-ph.HEhep-ph6 citations
33. 33*

    Rotating black holes in Randall-Sundrum II braneworlds

    William D. Biggs🇬🇧 · Jorge E. Santos🇬🇧

    We find rotating black hole solutions in the Randall-Sundrum II (RSII) model, by numerically solving a three-dimensional PDE problem using pseudospectral collocation methods. We compute the area and equatorial inner-most stable orbits of these solutions. For large black holes compared with the AdS length scale, $\ell$, the black hole exhibits four-dimensional behaviour, approaching the Kerr metric on the brane, whilst for small black holes, the solution tends instead towards a five-dimensional Myers-Perry black hole with a single non-zero rotation parameter aligned with the brane. This departure from exact four-dimensional gravity may lead to different phenomenological predictions for rotating black holes in the RSII model to those in standard four-dimensional general relativity. This letter provides a stepping stone for studying such modifications.

    ↳ hep-thgr-qchep-phPRL(2022)·15 citations
34. 34*

    Axion spectra and the associated x-ray spectra of low-mass stars

    Ilídio Lopes🇵🇹

    For the first time, we predict the axion spectra and their associated luminosities for several low-mass stars -- one and two solar masses stars in the main sequence and post-main sequence stages of evolution. Equally, we also compute the x-ray excess emission resulting from the conversion of axions back to photons in the presence of a strong magnetic field in the envelope of these stars. Hence, a given star will have a unique axion spectrum and $L_a$ axion luminosity. And if such star has a strong magnetic field in its stellar envelope, it will also show a characteristic x-ray spectrum and $L_{a\gamma }$ x-ray luminosity. Such radiation will add up to the x-ray electromagnetic spectrum and $L_X$ luminosity of the star. The present study focuses on axion models with an axion-photon coupling constant, $510^{-11}{\mathrm{GeV}}^{-1}$, a value just below the most recent upper limit of $6.610^{-11}{\mathrm{GeV}}^{-1}$ found by CAST and IAXO helioscopes. The range of axion parameters discussed here spans many axion models' parameter space, including the DFSZ and KSVZ models. We found that axions with a mass in the range $10^{-7}$ to $10^{-5}\mathrm{eV}$ and an axion-photon coupling constant of $510^{-11}{\mathrm{GeV}}^{-1}$ produce an axion emission spectra with an averaged axion energy that varies from 1 to 5 KeV, and an $L_a$ ranging from $10^{-6}$ to $710^{-3}{L}_{\odot }$. We also predict that $L_{a\gamma }$ varies from $510^{-8}$ to $10^{-5}{L}_{\odot }$ for stars with an averaged magnetic field of $310^4\mathrm{G}$ in their atmospheres. Most of these $L_{a\gamma }$ predictions are larger than the $L_X$ observed in some stars. Therefore, such preliminary results show the potential of the next generation of stellar x-ray missions to constrain several classes of axion models.

    ↳ astro-ph.HEastro-ph.COastro-ph.SRhep-phPRD(2021)·4 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.