Tue·Dec 28, 2021Tuesday·December 28, 2021

1. 01*

   Rings and strings: a basis for understanding subleading colour and QCD coherence beyond the two-jet limit

   Jeffrey R. Forshaw🇬🇧 · Jack Holguin🇬🇧 · Simon Plätzer🇦🇹

   Guided by the colour-diagonal structure of collinear singularities, we identify a set of kinematic basis functions that are well suited to the simplification of soft gluon emission amplitudes. In particular, these basis functions, which emerge naturally in the colour flow basis, isolate the subleading colour contributions and improve the statistical convergence of the CVolver amplitude-evolution code. They also allow us to extend current angular-ordered parton showers beyond the azimuthally-averaged, two-jet limit.

   hep-phJHEP(2022)·12 citations
2. 02*

   Muon g-2 in a Type-X 2HDM assisted by inert scalars: probing at the LHC

   Nabarun Chakrabarty🇮🇳

   A scenario augmenting the well known Type-X Two-Higgs doublet model (2HDM) with an additional inert doublet is proposed. The Type-X 2HDM is known to offer a solution to the muon $g-2$ anomaly for a light pseudoscalar. We show that the proposed framework can accomodate a heavier pseudoscalar on account of two-loop Barr-Zee (BZ) contributions to muon $g-2$ stemming from the inert doublet. We subsequently explore an interesting ${\tau }^{+}{\tau }^{-}+$ missing transverse energy signal that can be used to probe the present scenario at the 14 TeV LHC.

   hep-phPRD(2023)·4 citations
3. 03*

   ALP-Pions generalized

   Triparno Bandyopadhyay🇮🇳 · Subhajit Ghosh🇺🇸 · Tuhin S. Roy🇮🇳

   A light axion-like particle or an ALP not just gives rise to interesting and spectacular signals of new physics as final states in meson decays, it necessarily leaves tell-tale signatures in processes that involve standard model (SM) fields only (i.e., SM processes). These effects result in the violation of the Gell-Mann--Okubo mass relation, modified form factors, altered integrated and differential rates for various SM transitions etc. This suggests that in the presence of a low lying state, such as an ALP, extraction of masses, mixing angles, and form factors in an entirely data-driven way from meson-physics observables is a highly non-trivial exercise. However, once done correctly, these same observables may, in turn, provide important (indirect) bounds on ALP physics, which remain robust even in the limits where new physics effects conspire to weaken the bounds from direct searches. Starting with a generalized ALP-quark Lagrangian (where restrictions due to parity are removed) we demonstrate this approach by focussing on $K_{{\ell }_3}^{+}$ decays, where we derive (indirect) bounds on ALP physics using NA48/2 data and lattice results. We also find sum rules which not just show deviations in the presence of an ALP, but also give hints towards the specific nature of the ALP physics itself.

   hep-phhep-exhep-latPRD(2022)·14 citations
4. 04*

   On the tension between the latest \nova and T2K data

   Ushak Rahaman🇿🇦 · Sushant Raut🇮🇳

   The latest data from the T2K and \nova experiments show a tension in their preferred values of the oscillation parameters. In this work, we try to identify the source of the tension between the data from these two experiments. An analysis of their data from various channels (individually, and combined) shows that the tension arises primarily from the ${\nu }_e$ appearance data, and is compounded by the ${\bar{\nu }}_{\mu }$ disappearance data. We provide an explanation for the tension based on parameter degeneracies. Apart from the analysis with the standard matter effect, we also analyse the data with the vacuum oscillation hypothesis. We find that vacuum oscillations fit the data as well as matter effects do; and also reduce the tension between the two experiments. We have also done a study of the future run of NO$\nu$A, T2K and DUNE in the context of resolving this tension.

   hep-phhep-exhep-thEPJC(2022)·13 citations
5. 05*

   Heavy flavor molecular states with strangeness

   Kan Chen🇨🇳 · Bo Wang🇨🇳 · Shi-Lin Zhu🇨🇳

   We proposed a unified framework to describe the interactions of the observed $T_{cc}$, $P_c$, and $P_{cs}$ within a quark level interaction in our previous work. In this work, we generalize our framework to the loosely bound hadronic molecules composed of heavy flavor di-hadrons with strangeness. We predict the possible $D^{(\ast )}{D}_s^{(\ast )}$ molecular states in the SU(3) limit with the masses of the $P_c$ states as the inputs. We also investigate the baryon-meson and baryon-baryon systems and consider the SU(3) breaking effect in their flavor wave functions. We generalize our isospin criterion of the formation of heavy flavor di-hadron molecules to the $U/V$ spin case. For a specific heavy flavor meson-meson, baryon-meson, or baryon-baryon system, the interactions for the states with the same flavor and spin matrix elements can be related by a generalized flavor-spin symmetry.

   hep-phhep-exhep-latnucl-thPRD(2022)·28 citations
6. 06*

   Equation-of-motion and Lorentz-invariance relations for tensor-polarized parton distribution functions of spin-1 hadrons

   S. Kumano🇯🇵 · Qin-Tao Song🇨🇳

   Structure functions of polarized spin-1 hadrons will be measured at various accelerator facilities in the near future. Recently, transverse-momentum-dependent and collinear parton distribution functions were theoretically proposed at twist 3 and twist 4 in addition to the twist-2 ones, so that full investigations became possible for structure functions of spin-1 hadrons in the same level with those of the spin-1/2 nucleons. Furthermore, twist-3 tensor-polarized multiparton distribution functions were also recently found for spin-1 hadrons. In this work, we show relations among the collinear parton- and multiparton-distribution functions for spin-1 hadrons by using equation of motion for quarks. These relations are valuable in constraining the distribution functions and learning about multiparton correlations in spin-1 hadrons.

   hep-phhep-exhep-latnucl-thPLB(2022)·16 citations
7. 07*

   Ratios of Partial Wave Amplitudes in the Decays of $J=1$ and $J=2$ Mesons

   Vanamali Shastry🇵🇱

   We study the two-body decay of mesons using the covariant helicity formalism. We find that to explain the ratio of partials wave amplitudes (PWAs) of the decay, the Lagrangian must include derivative interactions in addition to contact interactions. We estimate the ratios of the coupling constants for the vector decays of the axial-vector, pseudovector and pseudotensor meson, and the tensor decays of the pseudotensor mesons by fitting the ratios of the PWAs to the available data and predict the ratios to some new decays.

   hep-phRev.Mex.Fis.Suppl.(2022)·2 citations
8. 08*

   Analysis of identified particle transverse momentum spectra produced in pp, p--Pb and Pb--Pb collisions at the LHC using Tsallis--Pareto-type function

   Pei-Pin Yang🇨🇳 · Mai-Ying Duan🇨🇳 · Fu-Hu Liu🇨🇳 · Raghunath Sahoo🇮🇳

   In the framework of a multi-source thermal model at the partonic-level, we have analyzed transverse momentum spectra of hadrons measured by the ALICE Collaboration in proton-proton ($pp$ or $p$-$p$) collisions at the center-of-mass energy of $\sqrt{s}=7$ and 13 TeV, proton-lead ($p$-Pb) collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, and lead-lead (Pb-Pb) collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV. For meson(baryon), the contributions of two(three) constituent quarks are considered, in which each quark contributes to hadron transverse momentum to obey the revised phenomenological Tsallis transverse momentum distribution for the Maxwell-Boltzmann particles (the TP-like function in short) with isotropic random azimuthal angle. Three main parameters, namely, the revised index $a_0$, effective temperature $T$, and entropy-related index $n$ are obtained, which show the same tendency for small and large systems with respect to the centrality (or multiplicity) of events, rest mass of hadrons, and constituent mass of quarks.

   hep-phhep-exnucl-exnucl-thSymmetry(2022)·13 citations
9. 09*

   Central exclusive diffractive production of two-pions from continuum and decays of resonances in the Regge-eikonal model

   R.A. Ryutin🇷🇺

   Calculations of central exclusive diffractive production (CEDP) of two pions via continuum and resonance mechanism are presented in the Regge-eikonal approach. Data from STAR, ISR, CDF and CMS were analysed and compared with theoretical description. Preliminary extraction of $f_0(500)$, $f_0(980)$ and $f_2(1270)$ couplings to Pomeron, and also $\rho$ meson contribution from photoproduction mechanism to the CEDP cross-section are considered. We show possible nuances and problems of calculations and prospects of investigations at present and future hadron colliders.

   hep-phEPJC(2023)·3 citations
10. 10*

    $tWZ$ production at NLO in QCD in the SMEFT

    Hesham El Faham🇧🇪

    At NLO in QCD, the $tWZ$ production process interferes with resonant LO processes, $t\bar{t}Z$ and $t\bar{t}$, and a method to meaningfully disentangle these overlapping processes needs to be employed. I discuss the diagram-removal procedure needed to obtain an operative definition of $tWZ$ at NLO accuracy. I also show the predictions we obtain in the context of the Standard Model and in the Standard Model Effective Field Theory including the relevant dimension-six SMEFT operators.

    hep-ph3 citations
11. 11*

    Scalar-pseudoscalar pair production at the Large Hadron Collider at NLO+NLL accuracy in QCD

    He-Yi Li🇨🇳 · Ren-You Zhang🇨🇳 · Yu Zhang🇨🇳 · Wen-Gan Ma🇨🇳 · Ming-Ming Long🇨🇳 · Shu-Xiang Li🇨🇳

    We thoroughly investigate both transverse momentum and threshold resummation effects on scalar-pseudoscalar pair production via quark-antiquark annihilation at the $13\text{TeV}$ Large Hadron Collider at QCD NLO+NLL accuracy. A factorization method is introduced to properly supplement the soft-gluon (threshold) resummation contribution from parton distribution functions to the resummed results obtained by the Collins-Soper-Sterman resummation approach. We find that the impact of the threshold-resummation improved PDFs is comparable to the resummation effect of the partonic matrix element and can even predominate in high invariant mass regions. Moreover, the loop-induced gluon-gluon fusion channel in the type-I two-Higgs-doublet model is considered in our calculation. The numerical results show that the electroweak production via quark-antiquark annihilation dominates over the gluon-initiated QCD production by $1\sim 2$ orders of magnitude.

    hep-phCPC(2021)·1 citation
12. 12*

    Study of charmless two-body baryonic $B$ decays

    Xiang-Nan Jin🇨🇳 · Chia-Wei Liu🇨🇳 · Chao-Qiang Geng🇨🇳

    We study the charmless two-body decays of $B\to {\mathbf{B}}_n{\overline{\mathbf{B}}}_n^{\prime }$ with $B=(B^{+},B^0,B_s^0)$ and ${\mathbf{B}}_n^{(\prime )}$ the low-lying octet baryons. The factorizable amplitudes are calculated by the modified bag model, while the nonfactorizable ones are extracted from the experimental data with the $SU(3{)}_F$ flavor symmetry. We are able to explain all current experimental measurements and provide predictions on the decay branching ratios in $B\to {\mathbf{B}}_n{\overline{\mathbf{B}}}_n^{\prime }$. Particularly, we find that $\mathcal{B}(B_s^0\to {\Xi }^0{\overline{\Xi }}^0)=(19.3\pm 2.7)\times 10^{-7}$ and $\mathcal{B}(B_s^0\to {\Xi }^{-}{\overline{\Xi }}^{-})=(19.4\pm 2.7)\times 10^{-7}$, which are sizable and able to be observed in the ongoing experiments at LHCb and BELLE-II. Furthermore, the decay branching ratios of $B_s^0\to (p\overline{p},n\overline{n})$ and $B^0\to ({\Xi }^0{\overline{\Xi }}^0,{\Sigma }^{+}{\overline{\Sigma }}^{+})$ are expected to be $O(10^{-10})$, which are suppressed due to the angular momentum conservation and chiral symmetry.

    hep-phhep-exPRD(2022)·7 citations
13. 13*

    Towards a Model of Quarks and Leptons

    Y. H. Ahn🇰🇷 · Sin Kyu Kang🇰🇷 · Hyun Min Lee🇰🇷

    We propose an extra-dimension framework on the orbifold $S^1/Z_2$ for understanding the origin of the fermion mass and mixing hierarchies. Introducing the flavor symmetry $G_F(=${\it non-Abelian}$\times${\it Abelian}) as well as the extra gauged $U(1)$ symmetries through the bulk, we regard the $SU(2)$ singlet and doublet fermions in the Standard Model (SM) to be localized at the separate 3-branes and let the extra $SU(2)$ singlet flavored fermions in the bulk couple to the SM fermions at the 3-branes. The extra $U(1)$ symmetries satisfy the $U(1)$ gravitational anomaly-free condition, playing a crucial role in achieving the desirable fermion mass and mixing hierarchies and making the flavored axion naturally light. The singlet scalar fields, the flavon fields, are responsible for the spontaneous breaking of $G_F$ on the two 3-branes, while the $SU(2)$ singlet flavored fermions are integrated out to give rise to the effective Yukawa couplings for the SM fermions, endowed with the information of $G_F$ breaking in the two sectors. The flavored axion from the PQ symmetry is also proposed for solving the strong CP problem and being a dark matter candidate in our model.

    hep-phPRD(2022)·5 citations
14. 14*

    Novel approaches in Hadron Spectroscopy

    JPAC Collaboration: Miguel Albaladejo🇪🇸 · Lukasz Bibrzycki🇵🇱 · Sebastian M. Dawid🇺🇸 · Cesar Fernandez-Ramirez🇲🇽 · Sergi Gonzalez-Solis🇺🇸 · Astrid N. Hiller Blin🇺🇸 · Andrew W. Jackura🇺🇸 · Vincent Mathieu🇪🇸 · Mikhail Mikhasenko🇩🇪 · Victor I. Mokeev🇺🇸 · Emilie Passemar🇺🇸 · Alessandro Pilloni🇮🇹 and 5 other authors

    The last two decades have witnessed the discovery of a myriad of new and unexpected hadrons. The future holds more surprises for us, thanks to new-generation experiments. Understanding the signals and determining the properties of the states requires a parallel theoretical effort. To make full use of available and forthcoming data, a careful amplitude modeling is required, together with a sound treatment of the statistical uncertainties, and a systematic survey of the model dependencies. We review the contributions made by the Joint Physics Analysis Center to the field of hadron spectroscopy.

    hep-phhep-exnucl-thPPNP(2022)·85 citations
15. 15*

    Leptoquark and vector-like quark extended models as the explanation of the muon $g-2$ anomaly

    Shi-Ping He🇰🇷

    Leptoquark (LQ) models can be the solution to the $(g-2{)}_{\mu }$ anomaly because of the chiral enhancements. In this work, we consider the models extended by the LQ and vector-like quark (VLQ) simultaneously, which can be used to explain the anomaly because of the top quark and top partner (denoted as $T$) mixing. For the one LQ and one VLQ extended models, there are contributions from the top and $T$ quark. In the minimal LQ models, only the $R_2$ and $S_1$ representations can lead to the chiral enhancements. Here, we find one new $S_3$ solution to the anomaly in the presence of $(X,T,B{)}_{L,R}$ triplet. We also consider the one LQ and two VLQ extended models, which can solve the anomaly even in the absence of top interactions and mixings. Then, we propose new LQ search channels under the constraints of $(g-2{)}_{\mu }$. Besides the traditional $t\mu$ decay channel, the LQ can also decay into $T\mu$ final states, which will lead to the characteristic multi-top and multi-muon signals at hadron colliders.

    hep-phhep-exPRD(2022)·14 citations
16. 16*

    The Scale of New Physics from the Higgs Couplings to $\gamma \gamma$ and $\gamma Z$

    Fayez Abu-Ajamieh🇮🇳

    Measuring the Higgs couplings accurately at colliders is one of the best routes for finding physics Beyond the Standard Model (BSM). If the measured couplings deviate from the SM predictions, then this would give rise to energy-growing processes that violate tree-level unitarity at some energy scale, indicating new physics. In this paper, we extend previous work on unitarity bounds from the Higgs potential and the Higgs couplings to vector bosons and the top quark; to the Higgs couplings to $\gamma \gamma$ and $\gamma Z$. We find that while the HL-LHC might be able to find new physics in the $\gamma Z$ sector, the scale of new physics in both sectors is mostly beyond its reach. However, accurate measurements of the leading couplings of the two sectors in the HL-LHC can place stringent limits on both the scale of new physics and on other Higgs couplings that are difficult to measure. In addition, the scale of new physics is mostly within the reach of the $100$ TeV collider.

    hep-phJHEP(2022)·18 citations
17. 17*

    QCD knows new quarks

    Chuan-Xin Cui🇨🇳 · Hiroyuki Ishida🇯🇵 · Mamiya Kawaguchi🇨🇳 · Jin-Yang Li🇨🇳 · Shinya Matsuzaki🇨🇳 · Akio Tomiya🇺🇸

    We find that a big gap between indicators for the breaking strengths of the global chiral SU(2) and U(1) axial symmetries in QCD of the Standard Model (SM) can be interpreted as a new fine-tuning problem. This may thus imply calling for a class of Beyond the SM, which turns out to favor having a new chiral symmetry and the associated massless new quark insensitive to the chiral SU(2) symmetry for the lightest up and down quarks, so that the fine-tuning is relaxed. Our statistical estimate shows that QCD of the SM is by more than 300 standard deviations off the desired parameter space, which is free from the fine-tuning, and the significance will be greater as the lattice measurements on the QCD hadron observables get more accurate. As one viable candidate, we introduce a dark QCD model with massless new quarks, which can survive current experimental, cosmological, and astrophysical limits, and also leave various phenomenological and cosmological consequences, to be probed in the future. This is a new indication from QCD, which gives a new avenue to deeper understand QCD, and provides a new guideline to consider going beyond the SM.

    hep-phhep-exhep-latnucl-thUniverse(2024)·1 citation
18. 18*

    On the Detection of QCD Axion Dark Matter by Coherent Scattering

    Hajime Fukuda🇺🇸 · Satoshi Shirai🇯🇵

    The QCD axion is a promising candidate of the dark matter. In this paper, we discuss elastic scattering processes between nucleons and the QCD axion dark matter. We point out that the cross section can be enhanced by more than $\mathcal{O}(10^{25})$ by the coherent effect, compared to classical processes. As a result, for example, we show that QCD axions may scatters at the sun with $\mathcal{O}(1)$ probability for $f_a\lesssim 10^{11}\text{GeV}$. In addition, one may expect stimulated emission effects can also enhance the cross section because the number density of the axion DM is very large. The enhancement factor can be as large as another $\mathcal{O}(10^{25})$ and, if the factor exists, the force from the dark matter wind may be detected via e.g., torsion balance experiments. However, it is also found that there is a cancellation of the stimulated emission factor and the force is too small to be detected.

    hep-phPRD(2022)·21 citations
19. 19*

    First Order Color Symmetry Breaking and Restoration Triggered by Electroweak Symmetry Non-restoration

    Wei Chao🇨🇳 · Huai-Ke Guo🇺🇸 · Xiu-Fei Li🇨🇳

    In this paper we propose a new approach for the spontaneous breaking and restoration of the $SU(3{)}_C$ color symmetry in the framework of electroweak symmetry non-restoration (EWSNR) at high temperature, which provides an alternative approach for the Baryogenesis. Due to the exotic high vacuum expectation value (VEV) of the SM Higgs doublet in EWSNR, the color symmetry can be spontaneous broken succeeding the electroweak phase transition whenever there is a negative quartic coupling between the SM Higgs and a scalar color triplet. The color symmetry is then restored at low temperature as the VEV of SM Higgs evolving to small value. We show that the phase transitions related to color breaking and restoration can be first order, and the stochastic gravitational wave (GW) signals are smoking-gun of these processes. We demonstrate the possibility of detecting these GW signals in future GW experiments such as DECIGO and BBO.

    hep-phastro-ph.COPLB(2024)·12 citations
20. 20*

    Probing double-aligned two Higgs doublet models at LHC

    Shinya Kanemura🇯🇵 · Michihisa Takeuchi🇯🇵 · Kei Yagyu🇯🇵

    We consider two Higgs doublet models (THDMs) with both the Higgs potential and Yukawa interactions being aligned, which we call "double-aligned THDMs". In this scenario, coupling constants of the discovered Higgs boson to the Standard Model (SM) particles are identical to those of the SM Higgs boson, and flavor changing neutral currents via neutral Higgs bosons do not appear at tree level. We investigate current constraints and future prospects of the model by using measurements from flavor experiments and data of multi-lepton final states at LHC. Especially, we focus on the electroweak pair production of the additional Higgs bosons with their masses below $2m_t$. We find that the most of the parameter space are already excluded by the current LHC data when the leptonic decays of the additional Higgs bosons are dominant, which can be interpreted to the scenario in the Type-X THDM as a special case. We also clarify the parameter region where the high-luminosity LHC can explore, and demonstrate the reconstruction of the masses of additional Higgs bosons from the $b\bar{b}{\tau }^{+}{\tau }^{-}$ final states in a few benchmark points.

    hep-phhep-exPRD(2022)·18 citations
21. 21*

    Light pseudoscalar meson and heavy meson scattering lengths to $\mathcal{O}(p^4)$ in heavy meson chiral perturbation theory

    Bo-Lin Huang🇨🇳 · Zi-Yang Lin🇨🇳 · Shi-Lin Zhu🇨🇳

    We calculate the threshold $T$ matrices of the light pseudoscalar meson and heavy meson scattering to fourth order in heavy meson chiral perturbation theory. We determine the low-energy constants by fitting to the lattice QCD data points through both the perturbative and iterated methods and obtain the physical scattering lengths in both formalisms. The values of the scattering lengths tend to be convergent at fourth order for most of the channels in the perturbative method. The value of the scattering length for the channel $DK(I=0)$, which involves the bound state $D_{s0}^{\ast }(2317)$, is obtained correctly in the iterated method. Based on the heavy diquark-antiquark symmetry, we also estimate the meson and doubly charmed (bottom) baryon scattering lengths, and find that the bound states can be generated with high probability in the channels $\bar{K}{\Xi }_{cc}(I=0)$ and $\bar{K}{\Xi }_{bb}(I=0)$. We strongly urge the LHCb Collaboration to look for the very narrow $\bar{K}{\Xi }_{cc}$ state with $I{J}^P=0{\frac{1}{2}}^{-}$ through either the electromagnetic decay or the iso-spin violating strong decay ${\Omega }_{cc}\pi$.

    hep-phhep-exhep-latnucl-thPRD(2022)·26 citations
22. 22*

    Running axial mass of the nucleon as a phenomenological tool for calculating QE neutrino-nucleus cross sections

    Igor D. Kakorin🇷🇺 · Konstantin S. Kuzmin🇷🇺 · Vadim A. Naumov🇷🇺

    We suggest an empirical rule-of-thumb for calculating the cross sections of charged-current quasielastic (CCQE) and CCQE-like interactions of neutrinos and antineutrinos with nuclei. The approach is based on the standard relativistic Fermi-gas model and on the notion of neutrino energy dependent axial-vector mass of the nucleon, governed by a couple of adjustable parameters, one of which is the conventional charged-current axial-vector mass. The inelastic background contributions and final-state interactions are therewith simulated using GENIE 3 neutrino event generator. An extensive comparison of our calculations with earlier and current accelerator CCQE and CCQE-like data for different nuclear targets shows good or at least qualitative overall agreement over a wide energy range. We also discuss some problematical issues common to several competing contemporary models of the CCQE (anti)neutrino-nucleus scattering and to the current neutrino interaction generators.

    hep-phhep-exEPJC(2021)·9 citations
23. 23*

    A new Direct Detection Strategy for the Cosmic Neutrino Background

    Wei Chao🇨🇳 · Jing-jing Feng🇨🇳 · Mingjie Jin🇨🇳 · Tong Li🇨🇳

    The direct detection of cosmic neutrino background (CNB) has been a longstanding challenge in particle physics, due to its low number density and tiny neutrino masses. In this work, we consider the spectrum of the CNB boosted by cosmic rays via the neutrino self-interaction, and calculate the event rate of the boosted CNB-plasmon scattering in term of the dielectric response, which accounts for in-medium screening effect of a condensed matter target. This can be taken as the new direct detection strategy for the CNB in complementary to the traditional one, which captures the CNB on a $\beta$-unstable nucleus. Our result shows that one can either see the event of the CNB for the exposure of per kg$\cdot$year, or puts a strong constraint on the neutrino self-interaction. We further explore the background induced by the sub-MeV dark matter and the boosted super-light dark matter.

    hep-phastro-ph.CO5 citations
24. 24*

    Two-particle Correlations in multi-Regge Kinematics

    N. Bethencourt de Leon🇪🇸 · G. Chachamis🇵🇹 · A. Sabio Vera🇪🇸

    Multi-jet production at the LHC is an important process to study. In particular, events with final state kinematic configurations where we have two jets widely separated in rapidity with similar pT and lots of mini-jets or jets populating the space in between are relevant for the high energy limit of QCD. Keeping the jet multiplicity fixed, the study of these events is a good ground to test different models of multi-particle production in hadron-hadron collisions. We report on a comparison between the predictions of the old multiperipheral Chew-Pignotti model and those of BFKL for the single jet rapidity distributions and for jet-jet rapidity correlations.

    hep-ph0 citations
25. 25*

    Composite Weak Bosons and Dark Matter

    H. Fritzsch🇩🇪

    The three weak bosons are bound states of two fermions and their antiparticles. There exist also two bound states of three fermions. One of them is neutral and stable. This particle provides the dark matter in our universe.

    hep-ph1 citation
26. 26*

    Beta-Decay Spectrum and Lorentz Violation

    Ralf Lehnert🇺🇸

    Relativity theory and its underlying Lorentz and CPT invariance represent key principles of physics and therefore require continued experimental scrutiny across the broadest possible range of energy scales and physical systems. Possibilities for tests of these symmetries in precision $\beta$-decay experiments with focus on KATRIN are investigated. It is found that countershaded departures from relativity, which represent a particular challenge to detection, are accessible in such experiments. In this context, it is argued that KATRIN would be in an excellent position to conduct the first-ever experimental search for countershaded Lorentz and CPT breaking in neutrinos.

    hep-phhep-exPLB(2022)·17 citations
27. 27*

    nuSQuIDS: A toolbox for neutrino propagation

    Carlos A. Argüelles🇺🇸 · Jordi Salvado🇪🇸 · Christopher N. Weaver🇺🇸

    The Neutrino Simple Quantum Integro-Differential Solver (nuSQuIDS) is a C++ code based on SQuIDS that propagates an ensemble of neutrinos through given media. Neutrino oscillation calculations relevant to current and next-generation experiments are implemented. This includes coherent and non-coherent neutrino interactions in settings such as the Sun, Earth, or a vacuum. The code is designed to be accurate and flexible, while at the same time maintaining good performance. It has a modular design that allows the user to incorporate new physics in novel scenarios.

    hep-phhep-exComput.Phys.Commun.(2022)·61 citations
28. 28*

    Energy dependence of the chiral magnetic effect in expanding holographic plasma

    Casey Cartwright🇺🇸 · Matthias Kaminski🇺🇸 · Bjoern Schenke🇺🇸

    Based on a holographic far-from-equilibrium calculation of the chiral magnetic effect~(CME) in an expanding quark gluon plasma, we study collisions at various energies. We compute the time evolution of the CME current in the presence of a time-dependent axial charge density and subject to a time-dependent magnetic field. The plasma expansion leads to a dilution of the CME current. We study distinct combinations of how the initial magnetic field and initial axial charge behave with changing initial energy as proposed in previous literature. Most scenarios we consider lead to an increasing time-integrated CME current, when increasing the initial energy. This would make it more likely to observe the CME at higher collision energies.

    hep-phhep-thnucl-thPRC(2022)·18 citations
29. 29*

    Exploring millicharged dark matter components from the shadows

    Lalit S. Bhandari🇮🇳 · Arun M. Thalapillil🇮🇳

    Dark matter sectors with hidden interactions have been of much interest in recent years. These frameworks include models of millicharged particles as well as dark sector bound states, whose constituents have electromagnetic gauge interactions. These exotic, charged states could constitute a part of the total dark matter density. In this work, we explore in some detail the various effects, on the photon sphere and shadow of spherically symmetric black holes, due to dark matter plasmas furnished by such sectors. Estimating physically viable parameter spaces for the particle physics models and taking semi-realistic astrophysical scenarios that are amenable to theoretical analyses, we point out various modifications and characteristics that may be present. Many of these effects are unique and very distinct from analogous situations with conventional baryonic plasmas, or neutral perfect fluid dark matter surrounding black holes. While in many physically viable regions of the parameter space the effects on the near-horizon regions and black hole shadows are small, in many parts of the low particle mass regions the effects are significant, and potentially measurable by current and future telescopes. Such deviations, for instance, include characteristic changes in the photon sphere and black hole shadow radii, unique thresholds for the dark matter plasma dispersion where the photon sphere or black hole shadow vanishes, and where the dark matter plasma becomes opaque to electromagnetic waves. Alternatively, we point out that a non-observation of such deviations and characteristics, in future, could put constraints on interesting regions of the particle physics parameter space.

    hep-phastro-ph.HEgr-qchep-ex+1JCAP(2022)·5 citations
30. 30*

    Improved cosmological constraints on the neutrino mass and lifetime

    Guillermo F. Abellán🇫🇷 · Zackaria Chacko🇺🇸 · Abhish Dev🇺🇸 · Peizhi Du🇺🇸 · Vivian Poulin🇫🇷 · Yuhsin Tsai🇺🇸

    We present cosmological constraints on the sum of neutrino masses as a function of the neutrino lifetime, in a framework in which neutrinos decay into dark radiation after becoming non-relativistic. We find that in this regime the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO) and (uncalibrated) luminosity distance to supernovae from the Pantheon catalog constrain the sum of neutrino masses $\sum m_{\nu }$ to obey $\sum m_{\nu }<0.42$ eV at (95$\%$ C.L.). While the the bound has improved significantly as compared to the limits on the same scenario from Planck 2015, it still represents a significant relaxation of the constraints as compared to the stable neutrino case. We show that most of the improvement can be traced to the more precise measurements of low-$\ell$ polarization data in Planck 2018, which leads to tighter constraints on ${\tau }_{\mathrm{reio}}$ (and thereby on $A_s$), breaking the degeneracy arising from the effect of (large) neutrino masses on the amplitude of the CMB power spectrum.

    hep-phastro-ph.COJHEP(2022)·74 citations
31. 31*

    Effects of variation of the fine structure constant $\alpha$ and quark mass $m_q$ in Mössbauer nuclear transitions

    Pavel Fadeev🇩🇪 · Julian C. Berengut🇦🇺 · Victor V. Flambaum🇦🇺

    High accuracy measurements in Mössbauer transitions open up the possibility to use them in the search for temporal and spatial variation of the fine-structure constant $\alpha$, quark mass $m_q$, and dark matter field which may lead to the variation of $\alpha$ and $m_q$. We calculate the sensitivity of nuclear transitions to variation of $\alpha$ and $m_q$. Mössbauer transitions have high sensitivity to variation of quark mass $m_q$ and the strong interaction scale ${\Lambda }_{QCD}$, to which atomic optical clocks are not sensitive. The enhancement factors $K$, defined by $\frac{\delta f}{f}=K_{\alpha }\frac{\delta \alpha }{\alpha }$ and $\frac{\delta f}{f}=K_q\frac{\delta m_q}{m_q}$ where $f$ is the transition energy, may be large in some transitions. The 8~eV nuclear clock transition in ${}^{229}$Th ($K_q\approx 10^4$) and 76~eV transition in ${}^{235}$U ($K_{\alpha }\approx K_q\approx 10^3$) may be investigated using laser spectroscopy methods.

    ↳ nucl-thhep-phnucl-exphysics.atom-phPRC(2022)·11 citations
32. 32*

    Cooling of Isolated Neutron Stars with Pion Condensation: Possible Fast Cooling in a Low-Symmetry-Energy Model

    Akira Dohi🇯🇵 · Helei Liu🇨🇳 · Tsuneo Noda🇯🇵 · Masa-aki Hashimoto🇯🇵

    We studied thermal evolution of isolated neutron stars (NSs) including the pion condensation core, with an emphasis on the stiffness of equation of state (EOS). Many temperature observations can be explained by the minimal cooling scenario which excludes the fast neutrino cooling process. However, several NSs are cold enough to require it. The most crucial problem for NS cooling theory is whether the nucleon direct Urca (DU) process is open. The DU process is forbidden if the nucleon symmetry energy is significantly low. Hence, another fast cooling process is required in such an EOS. As the candidate to solve this problem, we consider the pion condensation. We show that the low-symmetry-energy model can account for most cooling observations including cold NSs, with strong neutron superfluidity. Simultaneously, it holds the $2M_{\odot }$ observations even if the pion condensation core exists. Thus, we propose the possibility of pion condensation, as an exotic state to solve the problem in low-symmetry-energy EOSs. We examined the consistency of our EOSs with other various observations as well.

    ↳ astro-ph.HEhep-phnucl-thIJMPE(2022)·9 citations
33. 33*

    Generalized Logotropic Models and their Cosmological Constraints

    Hachemi B. Benaoum🇦🇪 · Pierre-Henri Chavanis🇫🇷 · Hernando Quevedo🇲🇽

    We propose a new class of cosmological unified dark sector models called "{\em Generalized Logotropic Models}". They depend on a free parameter $n$. The original logotropic model [P.H. Chavanis, Eur. Phys. J. Plus {\bf 130}, 130 (2015)] is a special case of our generalized model corresponding to $n=1$. In our scenario, the Universe is filled with a single fluid, a generalized logotropic dark fluid (GLDF), whose pressure $P$ includes higher order logarithmic terms of the rest-mass density ${\rho }_m$. The total energy density $ϵ$ is the sum of the rest-mass energy density ${\rho }_m{c}^2$ and the internal energy density $u$ which play the role of dark matter energy density ${ϵ}_m$ and dark energy density ${ϵ}_{de}$, respectively. We investigate the cosmological behavior of the generalized logotropic models by focusing on the evolution of the energy density, scale factor, equation of state parameter, decceleration parameter and squared speed of sound. Low values of $n\le 3$ are favored. We also study the asymptotic behavior of the generalized logotropic models. In particular, we show that the model presents a phantom behavior and has three distinct ways of evolution depending on the value of $n$. For $n\le 2$, it leads to a little rip and for $n>2$ to a big rip. We predict the value of the big rip time as a function of $n$ without any free (undetermined) parameter.

    ↳ gr-qcastro-ph.COastro-ph.GAhep-phUniverse(2022)·9 citations
34. 34*

    Two-point functions from chiral kinetic theory in magnetized plasma

    Lixin Yang🇨🇳

    We study the two-point functions from chiral kinetic theory which characterize the response to perturbative vector and axial gauge fields in magnetized chiral plasma. In the lowest Landau level approximation, the solution of chiral kinetic equations gives density waves of electric and axial charges, which contain chiral magnetic wave implied by the axial anomaly and magnetic field. We then obtain the constitutive relations for covariant currents and stress tensor that involving the density waves. By considering the difference between consistent and covariant anomalies explicitly, the correlators of consistent currents and stress tensor satisfy derivative symmetry, and therefore allow an effective action for the perturbative gauge fields as the generating functional of the correlators. We also verify the derivative symmetry of the correlators agrees with the Onsager relations.

    ↳ nucl-thhep-phhep-thPRD(2022)·3 citations
35. 35*

    Quark spin-orbit correlations in the proton

    M. Engelhardt🇺🇸 · J. R. Green🇮🇪 · N. Hasan🇩🇪 · T. Izubuchi🇺🇸 · C. Kallidonis🇺🇸 · S. Krieg🇩🇪 · S. Liuti🇺🇸 · S. Meinel🇺🇸 · J. Negele🇺🇸 · A. Pochinsky🇺🇸 · A. Rajan🇺🇸 · G. Silvi🇩🇪 · S. Syritsyn🇺🇸

    Generalized transverse momentum-dependent parton distributions (GTMDs) provide a comprehensive framework for imaging the internal structure of the proton. In particular, by encoding the simultaneous distribution of quark transverse positions and momenta, they allow one to directly access longitudinal quark orbital angular momentum, and, moreover, to correlate it with the quark helicity. The relevant GTMD is evaluated through a lattice calculation of a proton matrix element of a quark bilocal operator (the separation in which is Fourier conjugate to the quark momentum) featuring a momentum transfer (which is Fourier conjugate to the quark position), as well as the Dirac structure appropriate for capturing the quark helicity. The weighting by quark transverse position requires a derivative with respect to momentum transfer, which is obtained in unbiased fashion using a direct derivative method. The lattice calculation is performed directly at the physical pion mass, using domain wall fermions to mitigate operator mixing effects. Both the Jaffe-Manohar as well as the Ji quark spin-orbit correlations are extracted, yielding evidence for a strong quark spin-orbit coupling in the proton.

    ↳ hep-lathep-phPoS(2022)·13 citations
36. 36*

    Fifty ways to build a deuteron: a variational calculation of two-nucleon systems

    Michael L. Wagman (for the NPLQCD collaboration)🇺🇸

    A variational study of two-nucleon systems with lattice quantum chromodynamics is performed using a wide range of interpolating operators: dibaryon operators built from products of momentum-projected nucleons, hexaquark operators built from six spatially localized quarks, and quasi-local operators inspired by two-nucleon bound-state wavefunctions in nuclear effective field theories. Correlation-function matrices involving products of these operators are constructed by computing timeslice-to-all quark propagators with sparsening techniques. Comparisons between results obtained using the same gauge-field ensemble but different interpolating-operator sets demonstrate that interpolating-operator dependence can lead to significant effects on the two-nucleon energy spectra obtained using both variational and non-variational methods.

    ↳ hep-lathep-phnucl-thPoS(2022)·3 citations
37. 37*

    Inferring nuclear structure from heavy isobar collisions using Trajectum

    Govert Nijs🇺🇸 · Wilke van der Schee🇨🇭

    Nuclei with equal number of baryons but varying proton number (isobars) have many commonalities, but differ in both electric charge and nuclear structure. Relativistic collisions of such isobars provide unique opportunities to study the variation of the magnetic field, provided the nuclear structure is well understood. In this Letter we simulate collisions using several state-of-the-art parametrizations of the ${}_{40}^{96}$Zr and ${}_{44}^{96}$Ru isobars and show that a comparison with the exciting STAR measurement arXiv:2109.00131 of ultrarelativistic collisions can uniquely identify the structure of both isobars. This not only provides an urgently needed understanding of the structure of the Zirconium and Ruthenium isobars, but also paves the way for more detailed studies of nuclear structure using relativistic heavy ion collisions.

    ↳ nucl-thhep-phnucl-exSciPost Phys.(2023)·58 citations
38. 38*

    Partial Reduction and Cosmology at Defect Brane

    Zhi Wang🇨🇳 · Zekun Xu🇺🇸 · Shuyan Zhou🇨🇳 · Yang Zhou🇨🇳

    Partial reduction is a Randall-Sundrum reduction for only part of the AdS region between finite tension brane and zero tension brane. This is interesting in AdS/BCFT where the AdS bulk contains a defect brane. We employ partial reduction for a AdS bulk with a brane evolving as a $2d$ Friedmann-Robertson-Walker (FRW) cosmology and demonstrate the equivalence between defect extremal surface and island formula for a large subregion fine grained entropy in boundary CFT. We then move to higher dimensions and demonstrate the existence of $4d$ massless graviton on AdS${}_4$ brane in partial reduction. We also propose a partial reduction for a $4d$ FRW cosmology at defect brane and obtain the Newton constant by computing boundary entropy.

    ↳ hep-thgr-qchep-phJHEP(2022)·20 citations
39. 39*

    A test of spatial coincidence between CHIME FRBs and IceCube TeV energy neutrinos

    Shantanu Desai🇮🇳

    We search for a spatial association between the CHIME FRBs and IceCube neutrinos detected in the TeV energy range, by counting the total number of neutrino-FRB pairs with angular separations of $<3$ degrees, as well as within the observed neutrino error circle. This number constitutes the total signal events, which is then compared to the total background, corresponding to the null hypothesis of no spatial association. The background was obtained from the total neutrino-FRB matches in off-source angular windows with the same solid angle as the signal window. We do not find any statistically significant excess compared to the background. Therefore, we conclude that there is no evidence for an angular correlation between the IceCube neutrinos in the TeV energy range and CHIME FRBs. For each of these searches, we report 90% Bayesian credible interval upper limits on the observed FRB-induced neutrinos.

    ↳ astro-ph.HEhep-phJ.Phys.G(2023)·7 citations
40. 40*

    Confinement On the Moose Lattice

    Benjamin Lillard🇺🇸

    In this work we present a new class of N=1 supersymmetric confining gauge theories, with strikingly simple infrared theories that descend from intricate interconnected networks of product gauge groups. A diagram of the gauge groups and the charged matter content of the ultraviolet theory has the structure of a triangular lattice, with $SU(N)$ or $SU(3N)$ gauge groups at each of the vertices, connected by bifundamental chiral superfields. This structure admits a $U(1{)}_R$ conserving superpotential with marginal trilinear operators. With the introduction of this superpotential, the $SU(3N)$ and $SU(N)$ gauge groups confine: in the far infrared limit of the supersymmetric theory, the relevant degrees of freedom are gauge invariant "mesons" and "baryons." In this paper we show how the properties of the infrared degrees of freedom depend on the topology and shape of the moose/quiver ``lattice'' of the original gauge theory. We investigate various deformations of the theory, and propose some phenomenological applications for BSM models.

    ↳ hep-thhep-phJHEP(2022)·2 citations
41. 41*

    One Small Step for an Inflaton, One Giant Leap for Inflation: a novel non-Gaussian tail and primordial black holes

    Yi-Fu Cai🇨🇳 · Xiao-Han Ma🇨🇳 · Misao Sasaki🇯🇵 · Dong-Gang Wang🇬🇧 · Zihan Zhou🇺🇸

    We report a novel prediction from single-field inflation that even a tiny step in the inflaton potential can change our perception of primordial non-Gaussianities of the curvature perturbation. Our analysis focuses on the tail of probability distribution generated by an upward step transition between two stages of slow-roll evolution. The nontrivial background dynamics with off-attractor behavior is identified. By using a non-perturbative $\delta N$ analysis, we explicitly show that a highly non-Gaussian tail can be generated by a tiny upward step, even when the conventional nonlinearity parameters $f_{NL}$, $g_{NL}$, etc. remain small. With this example, we demonstrate for the first time the sensitive dependence of non-perturbative effects on the tail of probability distribution. Our scenario has an inconceivable application to primordial black holes by either significantly boosting their abundance or completely forbidding their appearance.

    ↳ astro-ph.COgr-qchep-phhep-thPLB(2022)·85 citations
42. 42*

    Very Hairy Inflation

    Guido D'Amico🇮🇹 · Nemanja Kaloper🇺🇸 · Alexander Westphal🇩🇪

    We revisit the rollercoaster cosmology based on multiple stages of monodromy inflation. Working within the framework of effective flux monodromy field theory, we include the full range of strong coupling corrections to the inflaton sector. We find that flattened potentials $V\sim {\varphi }^p+\dots$ with $p\lesssim 1/2$, limited to $N\lesssim 25-40$ efolds in the first stage of inflation, continue to fit the CMB. They yield $0.96\lesssim n_s\lesssim 0.97$, and produce relic gravity waves with $0.006\lesssim r\lesssim 0.035$, in full agreement with the most recent bounds from BICEP/{\it Keck}. The nonlinear derivative corrections generated by strong dynamics in EFT also lead to equilateral non-Gaussianity $f_{NL}^{eq}\simeq \mathcal{O}(1)-\mathcal{O}(10)$, close to the current observational bounds. Finally, in multi-stage rollercoaster, an inflaton-hidden sector $U(1)$ coupling can produce a tachyonic chiral vector background, which converts rapidly into tensors during the short interruption by matter domination. The produced stochastic gravity waves are chiral, and so they may be clearly identifiable by gravity wave instruments like LISA, Big Bang Observatory, Einstein Telescope, NANOgrav or SKA, depending on the precise model realization. We also point out that the current attempts to resolve the $H_0$ tension using early dark energy generically raise $n_s$. This may significantly alter the impact of BICEP/{\it Keck} data on models of inflation.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2022)·57 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.