Tue·Mar 29, 2022Tuesday·March 29, 2022

1. 01*

   Precision Early Universe Cosmology from Stochastic Gravitational Waves

   Dawid Brzeminski🇺🇸 · Anson Hook🇺🇸 · Gustavo Marques-Tavares🇺🇸

   The causal tail of stochastic gravitational waves can be used to probe the energy density in free streaming relativistic species as well as measure $g_{\star }(T)$ and beta functions $\beta (T)$ as a function of temperature. In the event of the discovery of loud stochastic gravitational waves, we demonstrate that LISA can measure the free streaming fraction of the universe down to the the $10^{-3}$ level, 100 times more sensitive than current constraints. Additionally, it would be sensitive to $\mathcal{O}(1)$ deviations of $g_{\star }$ and the QCD $\beta$ function from their Standard Model value at temperatures $\sim 10^5$ GeV. In this case, many motivated models such as split SUSY and other solutions to the Electroweak Hierarchy problem would be tested. Future detectors, such as DECIGO, would be 100 times more sensitive than LISA to these effects and be capable of testing other motivated scenarios such as WIMPs and axions. The amazing prospect of using precision gravitational wave measurements to test such well motivated theories provides a benchmark to aim for when developing a precise understanding of the gravitational wave spectrum both experimentally and theoretically.

   hep-phastro-ph.COgr-qcJHEP(2022)·37 citations
2. 02*

   Numerical calculation of 3-pion Coulomb scattering using scalar QED

   Dhevan Gangadharan🇺🇸

   The Coulomb scattering between three charged pions is shown to be perturbatively calculable using scalar QED for the relative momenta accessible to high-energy experiments of particle collisions. For the triplet relative momenta, $Q_3\gtrsim 50$ MeV/$c$, the calculated three-pion correlation function at $O({\alpha }^2)$ is very similar to the commonly-used triple-product of pair factors -- Riverside approximation. At lower $Q_3$, but above the lowest existing experimental measurement of $\sim 15$ MeV/$c$, terms of $O({\alpha }^3)$ or higher are needed to obtain a convincing description of three-pion Coulomb interactions. This is in contrast to two-pion correlations, for which the known exact solution is shown to be saturated by the lower orders at comparable pair relative momenta.

   hep-phnucl-exnucl-thPLB(2022)·0 citations
3. 03*

   Nucleon spin structure functions, considering target mass correction and higher twist effects at the NNLO accuracy and their transverse momentum dependence

   Abolfazl Mirjalili🇮🇷 · Shahin Atashbar Tehrani🇮🇷

   Using recent and updated world data on polarized structure functions $g_1$ and $g_2$ we perform QCD analysis at the next-next-to-leading-order (NNLO) accuracy. We include also target mass correction and higher twist effect to get more precise results in our fitting procedure. To confirm the validity of our fitting results several sum rules are examined and we do a comparison for them with results from other models. In our analysis we employ Jacobi polynomials approach to obtain analytical solutions of the DGLAP evolution equations for parton distribution functions (PDFs). Using the extracted PDFs from our data analysis as input we also compute the $x$- and ${\mathbf{p}}_T$-dependence of some transverse momentum dependence (TMD) PDFs in polarized case, based on covariant parton model. These functions are naively even time-reversal (T-even) at twist-2 approximation. The results for TMDs are indicating proper and acceptable behaviour with respect to what are presented in other literatures.

   hep-phPRD(2022)·11 citations
4. 04*

   Snowmass 2021 whitepaper: Proton structure at the precision frontier

   S. Amoroso · A. Apyan · N. Armesto · R.D. Ball · V. Bertone · C. Bissolotti · J. Bluemlein · R. Boughezal · G. Bozzi · D. Britzger · A. Buckley · A. Candido and 45 other authors

   An overwhelming number of theoretical predictions for hadron colliders require parton distribution functions (PDFs), which are an important ingredient of theory infrastructure for the next generation of high-energy experiments. This whitepaper summarizes the status and future prospects for determination of high-precision PDFs applicable in a wide range of energies and experiments, in particular in precision tests of the Standard Model and in new physics searches at the high-luminosity Large Hadron Collider and Electron-Ion Collider. We discuss the envisioned advancements in experimental measurements, QCD theory, global analysis methodology, and computing that are necessary to bring unpolarized PDFs in the nucleon to the N2LO and N3LO accuracy in the QCD coupling strength. Special attention is given to the new tasks that emerge in the era of the precision PDF analysis, such as those focusing on the robust control of systematic factors both in experimental measurements and theoretical computations. Various synergies between experimental and theoretical studies of the hadron structure are explored, including opportunities for studying PDFs for nuclear and meson targets, PDFs with electroweak contributions or dependence on the transverse momentum, for incisive comparisons between phenomenological models for the PDFs and computations on discrete lattice, and for cross-fertilization with machine learning/AI approaches. [Submitted to the US Community Study on the Future of Particle Physics (Snowmass 2021).]

   hep-phhep-exActa Phys.Polon.B(2022)·179 citations
5. 05*

   Electromagnetic transition amplitude for Roper resonance from holographic QCD

   Daisuke Fujii🇯🇵 · Akihiro Iwanaka🇯🇵 · Atsushi Hosaka🇯🇵

   The Roper resonance, the first excited state of the nucleon, Is one of the best-established baryon resonances. Yet, its properties have not been consistently explained by effective models of QCD, such as the non-relativistic quark model. In this letter, we propose an alternative approach in the Sakai-Sugimoto model that is one of the holographic models of QCD. In particular, we analyze the helicity amplitude of the electromagnetic transitions at the leading of 't~Hooft coupling $1/\lambda$. The model incorporates baryon structure at short distance by non-linear mesons surrounded by meson clouds at long distance. We demonstrate that the recently observed data by CLAS are explained in the present approach.

   hep-phPRD(2022)·7 citations
6. 06*

   Possible structure of the newly found exotic state ${\eta }_1(1855)$

   Bing-Dong Wan🇨🇳 · Sheng-Qi Zhang🇨🇳 · Cong-Feng Qiao🇨🇳

   Recently, a hadronic state named ${\eta }_1(1855)$, about 1.86 GeV, was observed in the BESIII experiment. This finding has a peculiar interest due to its exotic quantum number $J^{PC}=1^{-+}$. In this paper, we examine the tetraquark interpretation for the structure of ${\eta }_1(1855)$ in the configurations of $[1_c{]}_{\bar{s}s}\otimes [1_c{]}_{\bar{q}q}$ and $[1_c{]}_{\bar{s}q}\otimes [1_c{]}_{\bar{s}q}$, and perform a mass spectrum calculation in the framework of QCD sum rules. The results show that the observed ${\eta }_1(1855)$ could be embedded into the $[1_c{]}_{\bar{s}s}\otimes [1_c{]}_{\bar{q}q}$ configuration. The possible tetraquark and hybrid decay modes are analyzed, which are critical in decoding its inner structure. In the same way, we evaluate as well the $\bar{s}s\bar{s}s$ molecular state with $1^{-+}$ quantum number and find that there might exist two such ground states.

   hep-phPRD(2022)·55 citations
7. 07*

   Constraining non-dissipative transport coefficients in global equilibrium

   Shi-Zheng Yang🇨🇳 · Jian-Hua Gao🇨🇳 · Zuo-Tang Liang🇨🇳

   The fluid in global equilibrium must fulfill some constraints. These constraints can be derived from quantum statistical theory or kinetic theory. In this paper we will show that how these constraints can be applied to determine the non-dissipative transport coefficients for chiral systems along with the energy-momentum conservation, chiral anomaly for charge current and trace anomaly in energy-momentum tensor.

   hep-phhep-thnucl-thSymmetry(2022)·9 citations
8. 08*

   $B$ meson anomalies within the triplet vector boson model to the light of recent measurements from LHCb

   J. M. Cabarcas🇨🇴 · J. H. Muñoz🇨🇴 · Néstor Quintero🇨🇴 · Eduardo Rojas🇨🇴

   The triplet vector boson (TVB) is a simplified new physics model involving massive vector bosons transforming as a weak triplet vector. Such a model has been proposed as a combined explanation of the anomalous $b\to s{\mu }^{+}{\mu }^{-}$ and $b\to c\tau {\bar{\nu }}_{\tau }$ data (the so-called $B$ meson anomalies). In this work, we carry out an updated view of the TVB model by incorporating the most recent 2022 and 2023 LHCb measurements on the lepton flavor universality ratios $R(D^{(\ast )})=\mathrm{BR}(B\to D^{(\ast )}\tau {\bar{\nu }}_{\tau })/\mathrm{BR}(B\to D^{(\ast )}{\ell }^{\prime }{\bar{\nu }}_{{\ell }^{\prime }})$, $R({\Lambda }_c)=\mathrm{BR}({\Lambda }_b\to {\Lambda }_c\tau {\bar{\nu }}_{\tau })/\mathrm{BR}({\Lambda }_b\to {\Lambda }_c\mu {\bar{\nu }}_{\mu })$, and $R_{K^{(\ast )}}=\mathrm{BR}(B\to K^{(\ast )}{\mu }^{+}{\mu }^{-})/\mathrm{BR}(B\to K^{(\ast )}{e}^{+}{e}^{-})$. We perform a global fit to explore the allowed parameter space by the new data and all relevant low-energy flavor observables. Our results are confronted with the recent high-mass dilepton searches at the Large Hadron Collider (LHC). We find that for a heavy TVB mass of 1 TeV a common explanation of the $B$ meson anomalies is possible for all data with the recent LHCb measurements on $R(D^{(\ast )})$, in consistency with LHC constraints. However, this framework is in strong tension with LHC bounds when one considers all data along with the world average values (BABAR, Belle, and LHCb) on $R(D^{(\ast )})$. Future measurements will be required in order to clarify such a situation. In the end, the implications of our phenomenological analysis of the TVB model to some known flavor parametrizations are also discussed.

   hep-phhep-exPRD(2024)·0 citations
9. 09*

   Identifying a minimal flavor symmetry of the seesaw mechanism behind neutrino oscillations

   Zhi-zhong Xing🇨🇳

   In the canonical seesaw framework flavor mixing and CP violation in weak charged-current interactions of light and heavy Majorana neutrinos are correlated with each other and described respectively by the $3\times 3$ matrices $U$ and $R$. We show that the very possibility of $\left|U_{\mu i}^{}\right|=\left|U_{\tau i}^{}\right|$ (for $i=1,2,3$), which is strongly indicated by current neutrino oscillation data, automatically leads to a novel prediction $\left|R_{\mu i}^{}\right|=\left|R_{\tau i}^{}\right|$ (for $i=1,2,3$). We prove that behind these two sets of equalities and the experimental evidence for leptonic CP violation lies a minimal flavor symmetry -- the overall neutrino mass term keeps invariant when the left-handed neutrino fields transform as ${\nu }_{e\mathrm{L}}^{}\to ({\nu }_{e\mathrm{L}}^{}{)}^c$, ${\nu }_{\mu \mathrm{L}}^{}\to ({\nu }_{\tau \mathrm{L}}^{}{)}^c$, ${\nu }_{\tau \mathrm{L}}^{}\to ({\nu }_{\mu \mathrm{L}}^{}{)}^c$ and the right-handed neutrino fields undergo an arbitrary unitary CP transformation. Such a generalized $\mu$-$\tau$ reflection symmetry may help constrain the flavor textures of active and sterile neutrinos to some extent in the seesaw mechanism.

   hep-phJHEP(2022)·8 citations
10. 10*

    NLO QCD corrections to pseudoscalar quarkonium production with two heavy flavors in photon-photon collision

    Hao Yang🇨🇳 · Zi-Qiang Chen🇨🇳 · Cong-Feng Qiao🇨🇳

    We calculate the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to $\gamma +\gamma \to {\eta }_c+c+\bar{c}$, $\gamma +\gamma \to {\eta }_b+b+\bar{b}$ and $\gamma +\gamma \to B_c+b+\bar{c}$ processes in the framework of non-relativistic QCD (NRQCD) factorization formalism. The cross sections at the SuperKEKB electron-positron collider, as well as the future collider like the Circular Electron Positron Collider (CEPC), are evaluated. Numerical results indicate that the NLO corrections are significant, and the uncertainties in theoretical predictions with NLO corrections are reduced as expected. Due to the high luminosity of the SuperKEKB collider, the ${\eta }_c+c+\bar{c}$ production is hopefully observable in the near future.

    hep-phPRD(2022)·8 citations
11. 11*

    Tests of the Z_c-like Laplace Sum Rule (LSR) results using FESR at NLO

    R.M. Albuquerque (FAT-UERJ, Rio de Janeiro-BR)🇧🇷 · S. Narison (LUPM-CNRS-Montpellier-FR, iHEPMAD-Antananarivo-MG)🇫🇷 · D. Rabetiarivony (iHEPMAD-Antananarivo-MG)🇲🇬

    In this note, we use local duality Finite Energy Sum Rule (FESR) to test the validity of the Laplace sum rules (LSR) results truncated at the dimension-six condensates for the estimates of the masses and couplings of the Z_c-like ground states in Ref.1 by taking the example of the D^*D molecule configuration. We confirm the existence of an eventual (D^*D)_1 radial excitation with a mass around 5700 MeV and coupling of 197(25) keV to the current which may mask the eventual Z_c(4430) radial excitation candidate (named (D^*D)_0 in Ref.1) having a relatively small coupling f_{(D^*D)_0}=46(56) keV. We add more explanations on the estimates in Ref.1 from LSR and comment the results in Ref.2.

    hep-phhep-exhep-latPRD(2022)·3 citations
12. 12*

    Neutrino Masses and Mass Hierarchy: Evidence for the Normal Hierarchy

    Raul Jimenez🇪🇸 · Carlos Pena-Garay🇪🇸 · Kathleen Short🇪🇸 · Fergus Simpson🇬🇧 · Licia Verde🇪🇸

    The latest cosmological constraints on the sum of neutrino masses, in combination with the latest laboratory measurements on oscillations, provide ``decisive" Bayesian evidence for the normal neutrino mass hierarchy. We show that this result holds across very different prior alternatives by exploring two extremes on the range of prior choices. In fact, while the specific numerical value for the Evidence depends on the choice of prior, the Bayesian odds remain greater than 140:1 across very different prior choices. For Majorana neutrinos this has important implications for the upper limit of the neutrino-less double beta decay half life and thus for the technology and resources needed for future double beta decay experiments.

    hep-phastro-ph.COJCAP(2022)·55 citations
13. 13*

    Local one-dimensional reggeon model of the interaction of several pomerons

    M.A. Braun🇷🇺 · E.M. Kuzminskii🇷🇺 · M.I. Vyazovsky (Saint-Petersburg State University, Russia)🇷🇺

    We consider the one-dimensional local reggeon theory describing the leading pomeron with the conformal spin $l=0$ and two subdominant pomerons with $l=\pm 2$. The dependence of the propagators of pomerons and the $hA$ amplitude on rapidity are found numerically by integrating the evolution equation.

    hep-phhep-exEPJC(2022)·0 citations
14. 14*

    A new approach for amplitudes with multiple fermion lines

    Feng Zhang🇨🇳 · Bin Gong🇨🇳 · Jian-Xiong Wang🇨🇳

    A new approach for tree-level amplitudes with multiple fermion lines is presented. It mainly focuses on the simplification of fermion lines. By calculating two vectors recursively without any matrix multiplications, the result of a fermion line is reduced to a very compact form depending only on the two vectors. The comparisons with other packages are presented, and the results show that our package FDC gives a very good performance in the processes of multiple fermion lines with this new approach and some other improvements. A further comparison with WHIZARD shows that this new approach has a competitive efficiency in computing pure amplitude square without phase space integration.

    hep-phCPC(2022)·0 citations
15. 15*

    Detectable Gravitational Waves from preheating probes non-thermal Dark Matter

    Anish Ghoshal🇵🇱 · Pankaj Saha🇰🇷

    We describe the challenges and pathways when probing inflaton as dark matter with the stochastic gravitational waves (GWs) signal generated during the (p)reheating. Such scenarios are of utmost interest when no other interaction between the visible and dark sectors is present, therefore having no other detectability prospects. We consider the remnant energy in the coherently oscillating inflaton's zeroth mode to contribute to the observed relic dark matter density in the Universe. To fully capture the nonlinear dynamics and the effects of back-reactions during the oscillation, we resort to full nonlinear lattice simulation with pseudo-spectral methods to eliminate the differencing noises. We investigate for models whose behavior during the reheating era is of $m_{\Phi }^2{\Phi }^2$ type and find the typical primordial stochastic GWs backgrounds spectrum from scatterings among highly populated inflaton modes behaving like matter. We comment on the challenges of constructing such viable inflationary models such that the inflaton will account for the total dark matter of the universe while the produced GWs are within the future GWs detectors such as BBO, DECIGO, PTA, AION-MAGIS, and CE. We also describe the necessary modifications to the standard perturbative reheating scenario to prevent the depletion of residual inflaton energy via perturbative decay.

    hep-phastro-ph.COPRD(2024)·11 citations
16. 16*

    Electron-target experiment constraints on light dark matter produced in primordial black hole evaporation

    Tong Li🇨🇳 · Jiajun Liao🇨🇳

    Light sub-GeV dark matter (DM) particles in the Milky Way or macroscopic objects such as primordial black holes (PBHs) become attractive DM candidates due to null results of WIMP from direct detection experiments. We explore the possibility in which the present PBHs play as a novel source to produce light boosted DM and confine light PBHs with current and future terrestrial facilities. We study the electron elastic scattering data and obtain the current constraints from Super-Kamiokande and XENON1T on the boosted DM from PBH evaporation. The prospective bounds on the sub-GeV DM-electron scattering cross section and the fraction of DM composed of PBHs $f_{\mathrm{PBH}}$ are also imposed for future Xenon experiments.

    hep-phastro-ph.COhep-exPRD(2022)·18 citations
17. 17*

    Weak decays of triply heavy baryons in light front approach

    Wei Wang🇨🇳 · Zhi-Peng Xing🇨🇳

    We analyze weak decays of triply heavy baryon ${\Omega }_{ccc}^{++}$ and calculate the form factors for ${\Omega }_{ccc}^{++}\to {\Xi }_{cc}^{++}/{\Omega }_{cc}^{+}$ transitions in a light front quark model. The momentum distributions in form factors are accessed via the pole-model parametrization. Using the results for form factors, we predict decay branching fractions for semi-leptonic decays, and obtain $\mathcal{B}({\Omega }_{ccc}^{++}\to {\Xi }_{cc}^{+}{e}^{+}{\nu }_e)=0.08\%$, $\mathcal{B}({\Omega }_{ccc}^{++}\to {\Omega }_{cc}^{+}{e}^{+}{\nu }_e)=1.23\%$. Forward-backward asymmetry and angular distributions are then investigated in this work. We also estimate branching fractions for a few color-allowed processes and find that the ${\Omega }_{ccc}^{++}\to {\Omega }_{cc}^{+}{\pi }^{+}$ has a sizable branching fraction: $\mathcal{B}({\Omega }_{ccc}^{++}\to {\Omega }_{cc}^{+}{\pi }^{+})=1.82\%$. We point out that the ${\Omega }_{ccc}^{++}\to {\Omega }_{cc}^{+}{\pi }^{+}$ is a golden channel for the discovery of the ${\Omega }_{ccc}^{++}$. This analysis can provide a useful reference for future experimental search in future.

    hep-phPLB(2022)·20 citations
18. 18*

    Unveiling neutrino phenomenology, $(g-2{)}_{e,\mu }$ and leptogenesis through U(1) gauge symmetries in an inverse seesaw model

    Papia Panda🇮🇳 · Mitesh Kumar Behera🇮🇳 · Priya Mishra🇮🇳 · Rukmani Mohanta🇮🇳

    The proposed work is an extension of the Standard Model, where we have introduced two gauge symmetries, i.e., $U(1{)}_{B-L}$ and $U(1{)}_{L_e-L_{\mu }}$ to study neutrino phenomenology, muon, and electron $(g-2)$ as well as leptogenesis using the inverse seesaw mechanism. For this purpose, we have included three right-handed neutrinos $N_{R_i}$, three neutral fermions $S_{L_i}(i=1,2,3)$ and two scalar singlet bosons (${\chi }_1$ and ${\chi }_2$). We get a definite structure for the neutrino mass matrix due to the aforementioned gauge symmetries. Thus, our model is able to predict the neutrino oscillation results, which are in accordance with the experimental data and is inclined towards normal ordering. The outcomes comprise the active neutrino masses, mixing angles, mass squared differences, CP-violating phase, etc. Moreover, since the extended gauge symmetries are local, there are corresponding gauge bosons, denoted as $Z_{B-L}$ and $Z_{e\mu }$. Of these, mass of $Z_{B-L}$ is $\mathcal{O}$(TeV) range to satisfy the collider constraint, while the mass of $Z_{e\mu }$ is in the MeV range, making it feasible to account for current electron and muon $(g-2)$ results via neutral current interactions. Furthermore, our model is able to account for leptogenesis, which can demonstrate the matter-antimatter asymmetry of the universe. Additionally, we have carried out the prospect of probing our model in the context of upcoming long baseline experiments: DUNE, T2HK, and T2HKK, at a confidence level of $5\sigma$. From the result it is clear that, our model can be tested in its $3\sigma$ C.L. with $5\sigma$ allowed region of DUNE, T2HK and T2HKK.

    hep-phPRD(2023)·12 citations
19. 19*

    Deep Learning Jet Image as a Probe of Light Higgsino Dark Matter at the LHC

    Huifang Lv🇨🇳 · Daohan Wang🇨🇳 · Lei Wu🇨🇳

    Higgsino in supersymmetric standard models can play the role of dark matter particle. In conjunction with the naturalness criterion, the higgsino mass parameter is expected to be around the electroweak scale. In this work, we explore the potential of probing the nearly degenerate light higgsinos with machine learning at the LHC. By analyzing jet images and other jet substructure information, we use the Convolutional Neural Network(CNN) to enhance the signal significance. We find that our deep learning jet image method can improve the previous result based on the conventional cut-flow by about a factor of two at the High-Luminosity LHC.

    hep-phPRD(2022)·17 citations
20. 20*

    Two-Photon-Exchange effect in $ep\to en{\pi }^{+}$ at small $-t$ with the hadronic model and dispersion relation approach

    Qian-Qian Guo🇨🇳 · Hai-Qing Zhou🇨🇳

    In this work, the two-photon-exchange (TPE) effect in $ep\to en{\pi }^{+}$ at small $-t$ is discussed. In the previous work, the TPE contribution with one $\pi$ intermediate state is estimated numerically within a hadronic model under the pion-dominance approximation. Here we extend the discussion to include one $\rho$ intermediate state. The TPE contribution can be described by one scalar function in the limit $m_e\to 0$, the dispersion relation (DR) satisfied by this scalar function is analysed. The analytic expressions for the imaginary parts of the TPE contributions from one $\pi$ or one $\rho$ intermediate state are given within the hadronic model. Combining these analytic expressions and the DR, the corresponding real parts of the TPE contributions can be estimated easily at any available region. This can help the further experimental analysis to include the TPE contributions in a convenient way. The numeric results show that the TPE correction with one $\rho$ intermediate state is much smaller than that with one $\pi$ intermediate state in the current energy region. These results suggest that the TPE contribution with an elastic state is the main TPE contribution in $ep\to en{\pi }^{+}$ at small $-t$.

    hep-phhep-exnucl-exnucl-thPRC(2022)·6 citations
21. 21*

    Penguin Effects in $B_d^0\to J/\psi K_S^0$ and $B_s^0\to J/\psi \varphi$

    Marten Z. Barel🇳🇱 · Kristof De Bruyn🇳🇱 · Robert Fleischer🇳🇱 · Eleftheria Malami🇳🇱

    Controlling the contributions from doubly Cabibbo-suppressed penguin topologies in the decays $B_d^0\to J/\psi K_S^0$ and $B_s^0\to J/\psi \varphi$ is mandatory to reach the highest possible precision in the measurement of the $B_q^0$--${\bar{B}}_q^0$ ($q=d,s$) mixing phases ${\varphi }_d$ and ${\varphi }_s$. The penguin contributions can be determined using a strategy based on the $SU(3)$ flavour symmetry of QCD. Using the latest experimental data, we update our combined analysis of the decays $B_d^0\to J/\psi K_S^0$, $B_s^0\to J/\psi \varphi$ and their control channels $B_s^0\to J/\psi K_S^0$, $B_d^0\to J/\psi {\pi }^0$ and $B_d^0\to J/\psi {\rho }^0$. This allows us to simultaneously determine the penguin parameters and both mixing phases. We discuss how the branching fractions of these decays can be used to probe the size of non-factorisable $SU(3)$-breaking effects, which form the main theoretical uncertainty associated with our $SU(3)$-based strategy, and provide new insights into the factorisation approach.

    hep-phPoS(2023)·25 citations
22. 22*

    Modular symmetry of soft supersymmetry breaking terms

    Shota Kikuchi🇯🇵 · Tatsuo Kobayashi🇯🇵 · Kaito Nasu🇯🇵 · Hajime Otsuka🇯🇵 · Shohei Takada🇯🇵 · Hikaru Uchida🇯🇵

    We study the modular symmetry of soft supersymmetry breaking terms. Soft scalar masses and $A$-term coefficients are invariant under the modular symmetry when we regard $F$-term as a spurion with the modular weight $-2$. Their flavor structure is determined by the same symmetry as Yukawa couplings, i.e., fermion masses. The modular symmetric behavior of $\mu$-term and $B$-term depends on how the $\mu$-term is generated.

    hep-phhep-thPTEP(2022)·21 citations
23. 23*

    Probing the anomalous tqgamma couplings in photon-proton collisions

    Eda Alici

    The top quark flavor changing neutral current processes are extremely suppressed within the Standard Model. Nevertheless, they could be enhanced in a new physics model beyond the Standard Model. Investigating the top quark's flavor changing neutral current interactions at colliders would be an important test in terms of new physics. In this work, we examine the potentials of the processes $e^{-}p\to e^{-}{\gamma }^{\ast }p\to e^{-}{W}^{+}b{\gamma }^{\ast }\to e^{-}j\bar{j}b{\gamma }^{\ast }$ and $e^{-}p\to e^{-}{\gamma }^{\ast }p\to e^{-}{W}^{+}b{\gamma }^{\ast }\to e^{-}\text{l}{\nu }_{\text{l}}b{\gamma }^{\ast }$ at the FCC-eh with $\sqrt{s}=7.08$ and $10.0TeV$ to study anomalous $tq\gamma$ couplings via effective Lagrangians. We obtain $95\%$ confidence level sensitivities on the anomalous coupling parameters at the three FCC-eh energies and various integrated luminosities. We find that our limits are at least two orders of magnitude better than the current LHC experimental results.

    hep-ph
24. 24*

    Non-linear Breit-Wheeler pair production in collisions of bremsstrahlung $\gamma -$quanta and a tightly focussed laser pulse

    Alina Golub🇩🇪 · Selym Villalba-Chávez🇩🇪 · Carsten Müller🇩🇪

    Experimental efforts toward the detection of the nonperturbative strong-field regime of the Breit-Wheeler pair creation process plan to combine incoherent sources of GeV $\gamma$ quanta and the coherent fields of tightly focussed optical laser pulses. This endeavour calls for a theoretical understanding of how the pair yields depend on the applied laser field profile. We provide estimates for the number of produced pairs in a setup where the high-energy radiation is generated via bremsstrahlung. Attention is paid to the role of the transversal and longitudinal focussing of the laser field, along with the incorporation of a Gaussian pulse envelope. We compare our corresponding results with predictions from plane-wave models and determine the parameters of focused laser pulses which maximize the pair yield at fixed pulse energy. Besides, the impact of various super-Gaussian profiles for the laser pulse envelope and its transverse shape is discussed.

    hep-phphysics.atom-phPRD(2022)·21 citations
25. 25*

    Axion Electrodynamics in Strong Magnetic Backgrounds

    Selym Villalba-Chávez🇩🇪 · Anatoly E. Shabad🇷🇺 · Carsten Müller🇩🇪

    The overcritical regime of axion-electrodynamics (AED) is investigated. For magnetic fields larger than the characteristic scale linked to AED, quantum vacuum fluctuations due to axion-like fields can dominate over those associated with the electron-positron fields. This hypothetical regime of the dominance of AED over QED is predicted to induce strong birefringence and screening effects. We show that, if the magnetic field lines are curved, extraordinary photons could be canalized along the field direction. It is also shown that the running QED coupling depends on the magnetic field strength, and for certain energy regimes, it could be screened almost to zero, making the QED building blocks very weakly interacting between each other. The impact of this phenomenon on the radiation mechanism of pulsars is discussed.

    hep-phJ.Phys.Conf.Ser.(2022)·0 citations
26. 26*

    Snowmass 2021 White Paper: Charged lepton flavor violation in the tau sector

    Swagato Banerjee🇺🇸 · Vincenzo Cirigliano🇺🇸 · Mogens Dam🇩🇰 · Abhay Deshpande🇺🇸 · Luca Fiorini🇪🇸 · Kaori Fuyuto🇺🇸 · Ciprian Gal🇺🇸 · Tomáš Husek🇸🇪 · Emanuele Mereghetti🇺🇸 · Kevin Monsálvez-Pozo🇪🇸 · Haiping Peng🇨🇳 · Francesco Polci🇫🇷 and 6 other authors

    Charged lepton flavor violation has long been recognized as unambiguous signature of New Physics. Here we describe the physics capabilities and discovery potential of New Physics models with charged lepton flavor violation in the tau sector as its experimental signature. Current experimental status from the B-Factory experiments BaBar, Belle and Belle II, and future prospects at Super Tau Charm Factory, LHC, EIC and FCC-ee experiments to discover New Physics via charged lepton flavor violation in the tau sector are discussed in detail. Submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

    hep-phhep-ex69 citations
27. 27*

    Laser-assisted scattering of a muon neutrino by an electron within the Electroweak theory

    S. El Asri🇲🇦 · S. Mouslih🇲🇦 · M. Ouali🇲🇦 · S. Taj🇲🇦 · B Manaut🇲🇦

    In accordance with the electroweak theory, we perform, in the first-Born approximation, a detailed analytical treatment of the differential cross-section (DCS) for the elastic scattering process $e^{-}+{\nu }_{\mu }⟶e^{-}+{\nu }_{\mu }$ in both absence and presence of a circularly polarized laser field. This scattering process is examined by using Dirac-Volkov wave functions for charged particles within an external laser field. The theoretical results obtained for the differential cross-section without laser field are compared with other theoretical results within the framework of Fermi theory. These results revealed to us the most important points that contribute to the understanding of the electroweak theory role in solving the problem of unitarity violation of the differential cross-section in Fermi theory. The differential cross section is modified significantly by inserting the electrons into an electromagnetic field. In addition, the influence of the laser strength and its frequency on the photons exchange between the colliding system and the laser field are also included and discussed. These effects are heavily related to the order and argument of the ordinary Bessel functions introduced in the theoretical calculation.

    hep-phLaser Phys.(2022)·2 citations
28. 28*

    Extraction of the higher-twist parton distribution $e(x)$ from CLAS data

    Aurore Courtoy🇲🇽 · Angel Miramontes🇲🇽 · Harut Avakian🇺🇸 · Marco Mirazita🇮🇹 · Silvia Pisano🇮🇹

    This manuscript presents the new analysis of recent CLAS and CLAS12 data aimed at the extraction of $e(x)$. This publication benefits from a proof-of-principle analysis of a smaller preliminary data set published in a preprint form in \url{1405.7659}. We present the first point-by-point extraction of a twist-3 PDF. The scalar PDF, $e(x)$, is accessed through the analysis of the data for the $\sin {\varphi }_R$-moment of the beam-spin asymmetry for dihadron production in semi-inclusive DIS off proton target at CLAS and CLAS12. The dihadron formalism allows for use of collinear framework, hence calling for a minimal set of approximations and hypotheses. The extracted PDF $e(x)$ carries insights into the physics of the largely-unexplored quark-gluon correlations, and its first Mellin moment is related to the marginally-known scalar charge of the nucleon. We show that the proton flavor combination of the scalar PDF is non-zero at more than $74\%$ probability.

    hep-phPRD(2022)·30 citations
29. 29*

    Visible Neutrino Decays and the Impact of the Daughter-Neutrino Mass

    André de Gouvêa🇺🇸 · Manibrata Sen🇩🇪 · Jean Weill🇺🇸

    We compute the differential decay width of two- and three-body neutrino decays, assuming neutrinos are Dirac fermions and allowing for the possibility that the decay-daughters have nonzero masses. We examine different hypotheses for the interaction that mediates neutrino decay and concentrate on identifying circumstances where the decay-daughters can significantly impact the neutrino-decay signature at different experiments. We are especially interested in decay daughters produced by right-chiral neutrino fields, when the mass of the daughter plays a decisive role. As a concrete example, we compare the effects of visible and invisible antineutrino decays at the JUNO experimental setup.

    hep-phhep-exPRD(2022)·10 citations
30. 30*

    Current and future neutrino limits on the abundance of primordial black holes

    Nicolás Bernal🇨🇴 · Víctor Muñoz-Albornoz🇪🇸 · Sergio Palomares-Ruiz🇪🇸 · Pablo Villanueva-Domingo🇪🇸

    Primordial black holes (PBHs) formed in the early Universe are sources of neutrinos emitted via Hawking radiation. Such astrophysical neutrinos could be detected at Earth and constraints on the abundance of comet-mass PBHs could be derived from the null observation of this neutrino flux. Here, we consider non-rotating PBHs and improve constraints using Super-Kamiokande neutrino data, as well as we perform forecasts for next-generation neutrino (Hyper-Kamiokande, JUNO, DUNE) and dark matter (DARWIN, ARGO) detectors, which we compare. For PBHs less massive than $\sim \text{few}\times 10^{14}$ g, PBHs would have already evaporated by now, whereas more massive PBHs would still be present and would constitute a fraction of the dark matter of the Universe. We consider monochromatic and extended (log-normal) mass distributions, and a PBH mass range spanning from $10^{12}$ g to $\sim 10^{16}$ g. Finally, we also compare our results with previous ones in the literature.

    hep-phastro-ph.COJCAP(2022)·49 citations
31. 31*

    Pure Quark and Gluon Observables in Collinear Drop

    Iain W. Stewart🇺🇸 · Xiaojun Yao🇺🇸

    We construct a class of pure quark and gluon observables by using the collinear drop grooming technique. The construction is based on linear combinations of multiple cumulative distributions of the jet mass in collinear drop, whose specific weights are fully predicted perturbatively. This yields observables which obtain their values purely from quarks (or purely from gluons) in a wide region of phase space. We demonstrate this by showing that these observables are effective in two phase space regions, one dominated by perturbative resummation and one dominated by nonperturbative effects. The nonperturbative effects are included using shape functions which only appear as a common factor in the linear combinations constructed. We test this construction using a numerical analysis with next-to-leading logarithmic resummation and various shape function models, as well as analyzing these observables with Pythia and Vincia. Choices for the collinear drop parameters are optimized for experimental use.

    hep-phhep-exnucl-thJHEP(2022)·15 citations
32. 32*

    Rare radiative decays of charm baryons

    Nico Adolph🇩🇪 · Gudrun Hiller🇩🇪

    We study weak radiative $|\Delta c|=|\Delta u|=1$ decays of the charmed anti-triplett (${\Lambda }_c$, ${\Xi }_c^{+}$, ${\Xi }_c^0$) and sextet (${\Sigma }_c^{++}$, ${\Sigma }_c^{+}$, ${\Sigma }_c^0$, ${\Xi }_c^{\prime +}$, ${\Xi }_c^{\prime 0}$, ${\Omega }_c$) baryons in the standard model (SM) and beyond. We work out $SU(2)$ and $SU(3{)}_F$-symmetry relations. We propose to study self-analyzing decay chains such as ${\Xi }_c^{+}\to {\Sigma }^{+}(\to p{\pi }^0)\gamma$ and ${\Xi }_c^0\to \Lambda (\to p{\pi }^{-})\gamma$, which enable new physics sensitive polarization studies. SM contributions can be controlled by corresponding analysis of the Cabibbo-favored decays ${\Lambda }_c^{+}\to {\Sigma }^{+}(\to p{\pi }^0)\gamma$ and ${\Xi }_c^0\to {\Xi }^0(\to \Lambda {\pi }^0)\gamma$. Further tests of the SM are available with initially polarized baryons including ${\Lambda }_c\to p\gamma$ together with ${\Lambda }_c\to {\Sigma }^{+}\gamma$ decays, or ${\Omega }_c\to {\Xi }^0\gamma$ together with ${\Omega }_c\to (\Lambda ,{\Sigma }^0)\gamma$. In addition, CP-violating new physics contributions to dipole operators can enhance CP-asymmetries up to few percent.

    hep-phPRD(2022)·16 citations
33. 33*

    Dark Matter and $(g-2{)}_{\mu ,e}$ in radiative Dirac neutrino mass models

    Talal Ahmed Chowdhury🇧🇩 · Md. Ehsanuzzaman🇧🇩 · Shaikh Saad🇨🇭

    The origin of neutrino mass is a mystery, so is its nature, namely, whether neutrinos are Dirac or Majorana particles. On top of that, hints of large deviations of the muon and the electron anomalous magnetic moments (AMMs) are strong evidence for physics beyond the Standard Model. In this work, piecing these puzzles together, we propose a class of radiative Dirac neutrino mass models to reconcile $(g-2{)}_{\mu ,e}$ anomalies with neutrino oscillation data. In this framework, a common set of new physics (NP) states run through the loops that generate non-zero neutrino mass and, due to chiral enhancement, provide substantial NP contributions to lepton AMMs. In addition, one of the three models studied in this work offers a Dark Matter candidate automatically stabilized by the residual symmetry, whose phenomenology is non-trivially connected to the other two puzzles mentioned above. Finally, our detailed numerical analysis reveals a successful resolution to these mysteries while being consistent with all colliders and cosmological constraints.

    hep-phJCAP(2022)·25 citations
34. 34*

    New Higgs decays to axion-like particles

    Anke Biekötter🇬🇧 · Mikael Chala🇪🇸 · Michael Spannowsky🇬🇧

    We investigate the interactions of a light scalar with the Higgs boson and second-generation fermions, which trigger new rare decays of the Higgs boson into $4\mu$, $2\mu 2\gamma$, $6\mu$ and $4\mu 2j$. We recast current LHC searches to constrain these decays and develop new collider analyses for those channels which are only poorly tested by existing studies. With the currently collected data we can probe branching ratios as small as $1.5\times 10^{-5}$, $8.7\times 10^{-5}$, $5.7\times 10^{-8}$ and $1.6\times 10^{-7}$, respectively. For the High-Luminosity LHC run, considered here to involve 3 ab${}^{-1}$ of integrated luminosity, these numbers go down to $1.3\times 10^{-5}$, $2.0\times 10^{-6}$, $3.0\times 10^{-9}$ and $5.4\times 10^{-9}$, respectively. We also comment on other channels that remain still unexplored.

    hep-phPLB(2022)·8 citations
35. 35*

    The pion-nucleon sigma term from Lattice QCD

    Rajan Gupta🇺🇸 · Tanmoy Bhattacharya🇺🇸 · Martin Hoferichter🇨🇭 · Emanuele Mereghetti🇺🇸 · Sungwoo Park🇺🇸 · Boram Yoon🇺🇸

    We summarize recent evidence, both from lattice QCD and chiral perturbation theory, that suggests that larger-than-expected excited-state contamination could be the reason for the tension between phenomenological determinations and previous direct lattice-QCD calculations of the pion--nucleon sigma term ${\sigma }_{\pi N}$. In addition, we extend the $\chi$PT analysis by calculating the corrections due to including the $\Delta (1232)$ resonance as an explicit degree of freedom. This correction is found to be small, thereby corroborating the excited-state effects found in the $\Delta$-less calculation and the result for ${\sigma }_{\pi N}$.

    ↳ hep-lathep-phnucl-thPoS(2024)·11 citations
36. 36*

    Mapping out the thermodynamic stability of a QCD equation of state with a critical point using active learning

    D. Mroczek🇺🇸 · M. Hjorth-Jensen🇺🇸 · J. Noronha-Hostler🇺🇸 · P. Parotto🇺🇸 · C. Ratti🇺🇸 · R. Vilalta🇺🇸

    The Beam Energy Scan Theory (BEST) collaboration's equation of state (EoS) incorporates a 3D Ising model critical point into the Quantum Chromodynamics (QCD) equation of state from lattice simulations. However, it contains 4 free parameters related to the size and location of the critical region in the QCD phase diagram. Certain combinations of the free parameters lead to acausal or unstable realizations of the EoS that should not be considered. In this work, we use an active learning framework to rule out pathological EoS efficiently. We find that checking stability and causality for a small portion of the parameters' range is sufficient to construct algorithms that perform with $>$96% accuracy across the entire parameter space. Though in this work we focus on a specific case, our approach can be generalized to any EoS containing a parameter space-class correspondence.

    ↳ nucl-thhep-phPRC(2023)·26 citations
37. 37*

    Improving Robustness of Jet Tagging Algorithms with Adversarial Training

    Annika Stein🇩🇪 · Xavier Coubez🇩🇪 · Spandan Mondal🇩🇪 · Andrzej Novak🇩🇪 · Alexander Schmidt🇩🇪

    Deep learning is a standard tool in the field of high-energy physics, facilitating considerable sensitivity enhancements for numerous analysis strategies. In particular, in identification of physics objects, such as jet flavor tagging, complex neural network architectures play a major role. However, these methods are reliant on accurate simulations. Mismodeling can lead to non-negligible differences in performance in data that need to be measured and calibrated against. We investigate the classifier response to input data with injected mismodelings and probe the vulnerability of flavor tagging algorithms via application of adversarial attacks. Subsequently, we present an adversarial training strategy that mitigates the impact of such simulated attacks and improves the classifier robustness. We examine the relationship between performance and vulnerability and show that this method constitutes a promising approach to reduce the vulnerability to poor modeling.

    ↳ physics.data-ancs.LGhep-exhep-phComput.Softw.Big Sci.(2022)·21 citations
38. 38*

    Japan's Strategy for Future Projects in High Energy Physics

    M. Endo · K. Hamaguchi🇯🇵 · M. Ibe🇯🇵 · T. Ishibashi · A. Ishikawa🇯🇵 · M. Ishino · M. Ishitsuka · S. Kanemura🇯🇵 · M. Kuriki · T. Mori · S. Moriyama🇯🇵 · H. Nanjo · W. Ootani · Y. Sato🇯🇵

    The current strategy for future projects of the Japanese high energy physics community, Japan Association of High Energy Physicists (JAHEP), remains as described in the Final Report of the Committee on Future Projects in High Energy Physics, published in 2017. The Recommendation part of the Final Report is excerpted in the following page. This document updates the Final Report by adding developments and advances that have occurred since 2017.

    ↳ hep-exhep-phphysics.acc-phphysics.ins-det8 citations
39. 39*

    Phase transitions and resilience of the MDCDW phase at finite temperature and density

    William Gyory🇺🇸 · Vivian de la Incera🇺🇸

    We study the phase transitions of the magnetic dual chiral density wave (MDCDW). This spatially inhomogeneous phase emerges in cold, dense QCD in the presence of a strong magnetic field. Starting from the generalized GL expansion of the free energy, we derive several analytical formulas that enable fast numerical computation of the expansion coefficients to arbitrary order, allowing high levels of precision in the determination of the physical dynamical parameters, as well as in the transition curves in the temperature vs. chemical potential plane at different magnetic fields. At magnetic fields and temperatures compatible with neutron star (NS) conditions, the MDCDW remains favored over the symmetric ground state at all densities. The phase's "resilience" manifests in (1) a region of small but nonzero remnant mass and significant modulation at intermediate densities, originating in part from the nontrivial topology of the lowest Landau level, and (2) a region of increasing condensate parameters at high densities. Our analysis suggests the MDCDW condensate remains energetically favored at densities and temperatures much higher than previously considered, opening the possibility for this phase to be a viable candidate for the matter structure of even young neutron stars produced by NS mergers.

    ↳ nucl-thastro-ph.HEhep-phPRD(2022)·20 citations
40. 40*

    Matrix method for perturbed black hole metric with discontinuity

    Shui-Fa Shen🇨🇳 · Wei-Liang Qian🇨🇳 · Kai Lin🇨🇳 · Cheng-Gang Shao🇨🇳 · Yu Pan🇨🇳

    Recent studies based on the notion of black hole pseudospectrum indicated substantial instability of the fundamental and high-overtone quasinormal modes. Besides its theoretical novelty, the details about the migration of the quasinormal mode spectrum due to specific perturbations may furnish valuable information on the properties of associated gravitational waves in a more realistic context. This work generalizes the matrix method for black hole quasinormal modes to cope with a specific class of perturbations to the metric featured by discontinuity, which is known to be intimately connected with the quasinormal mode structural instability. In practice, the presence of discontinuity poses a difficulty so that many well-known approaches for quasinormal modes cannot be straightforwardly applied. By comparing with other methods, we show that the modified matrix method is efficient, which can be used to solve for the low-lying modes with reasonable precision. Therefore, it might serve as an alternative gadget for relevant studies.

    ↳ gr-qchep-phClass.Quant.Grav.(2022)·20 citations
41. 41*

    Cosmological Krylov Complexity

    Kiran Adhikari🇩🇪 · Sayantan Choudhury🇮🇳

    In this paper, we study the Krylov complexity ($K$) from the planar/inflationary patch of the de Sitter space using the two mode squeezed state formalism in the presence of an effective field having sound speed $c_s$. From our analysis, we obtain the explicit behavior of Krylov complexity ($K$) and lancoz coefficients ($b_n$) with respect to the conformal time scale and scale factor in the presence of effective sound speed $c_s$. Since lancoz coefficients ($b_n$) grow linearly with integer $n$, this suggests that universe acts like a chaotic system during this period. We also obtain the corresponding Lyapunov exponent $\lambda$ in presence of effective sound speed $c_s$. We show that the Krylov complexity ($K$) for this system is equal to average particle numbers suggesting it's relation to the volume. Finally, we give a comparison of Krylov complexity ($K$) with entanglement entropy (Von-Neumann) where we found that there is a large difference between Krylov complexity ($K$) and entanglement entropy for large values of squeezing amplitude. This suggests that Krylov complexity ($K$) can be a significant probe for studying the dynamics of the cosmological system even after the saturation of entanglement entropy.

    ↳ hep-thcond-mat.stat-mechgr-qchep-ph+1Fortsch.Phys.(2022)·66 citations
42. 42*

    Chiral sum rule on the light front and the 3D image of the pion

    Yang Li🇨🇳 · Pieter Maris🇺🇸 · James P. Vary🇺🇸

    The lightest meson, the pion, features two faces -- one is the elementary Goldstone boson of QCD and the other is the structured bound state of quarks and gluons. To accommodate both in a single light-front wave function in the valence space, we obtain a sum rule by analyzing the conserved axial-vector current and the general structures of the wave functions. Using an analytic model motivated by holography, we show this sum rule is consistent with requirements of chiral symmetry breaking in AdS/QCD. Within this model, we find a remarkable feature of the pion, namely that the density is mostly uniform inside its radius; furthermore, we obtain good agreement with the experimental pion form factor at spacelike momenta.

    ↳ hep-thhep-phnucl-thPLB(2023)·12 citations
43. 43*

    Reduction of General One-loop Integrals Using Auxiliary Vector

    Bo Feng🇨🇳 · Tingfei Li🇨🇳 · Hongbin Wang🇨🇳 · Yaobo Zhang🇨🇳

    As a key method to deal with loop integrals, Integration-By-Parts (IBP) method can be used to do reduction as well as establish the differential equations for master integrals. However, when talking about tensor reduction, the Passarino-Veltman (PV) reduction method is also widely used for one-loop integrals. Recently, we have proposed an improved PV reduction method, i.e., the PV reduction method with auxiliary vector $R$, which can easily give analytical reduction results for any tensor rank. However, our results are only for integrals with propagators with power one. In this paper, we generalize our method to one-loop integrals with general tensor structures and propagators with general powers. Our ideas are simple. We solve the generalised reduction problem by combining differentiation over masses and proper limit of reduction with power-one propagators. Finally, we demonstrate our method with several examples. With the result in this paper, we have shown that our improved PV-reduction method with auxiliary vector is a self-completed reduction method for one-loop integrals.

    ↳ hep-thhep-phJHEP(2022)·19 citations
44. 44*

    Radiation from cold molecular clouds and Sun chromosphere produced by anti-quark nugget dark matter

    V.V. Flambaum🇦🇺 · I.B. Samsonov🇦🇺

    We study astrophysical implications of the quark nugget model of dark matter and propose observational techniques for detecting anti-Quark Nuggets (anti-QNs) with modern telescopes. Anti-QNs are compact composite objects of antiquark matter with a typical radius $R\sim 10^{-5}$ cm and density exceeding that of nuclear matter. Atoms and molecules of interstellar medium collide with anti-quark nuggets and annihilate. We estimate thermal radiation from anti-QNs in cold molecular clouds in our galaxy and show that this radiation appears sufficiently strong to be observed in infrared and visible spectra. Proton annihilation on anti-QNs produces $\gamma$-photons with energies in the range 100-400 MeV which may be detected by telescopes such as Fermi-LAT. We have found that anti-QN radiation inside the solar corona is too weak to produce a significant plasma heating or any other observable effects, while the radiation of $\gamma$-photons from the chromosphere may be observable. We also address the problem of survival of anti-quark nuggets in the early universe.

    ↳ astro-ph.GAastro-ph.HEastro-ph.SRhep-phPRD(2022)·7 citations
45. 45*

    Hyperbolic inflation in the Jordan frame

    Andronikos Paliathanasis🇿🇦

    We consider a multi-scalar field model in the Jordan frame which can be seen as a two-scalar field model where the Brans-Dicke field interacts in the kinetic part with the second scalar field. This theory under a conformal transformation reduces to the hyperbolic inflation. We show that scaling solutions and the de Sitter universe are provided by theory. In the study of asymptotic dynamics, we determine an attractor where all the fluid sources contribute in the cosmological fluid. This attractor is always a spiral and it can be seen as the analogue of the hyperbolic inflation in the Jordan frame.

    ↳ gr-qchep-phmath-phmath.MPUniverse(2022)·7 citations
46. 46*

    Stability of Yang Mills Vacuum State

    George Savvidy🇬🇷

    We examine the phenomena of the chromomagnetic gluon condensation in the Yang-Mills theory and the problem of stability of the chromomagnetic vacuum fields. The apparent instability of the chromomagnetic vacuum fields is a result of quadratic approximation. The stability is restored when the nonlinear interaction of negative/unstable modes is taken into account in the case of chromomagnetic vacuum fields and the interaction of the zero modes in the case of (anti)self-dual covariantly-constant vacuum fields. All these vacuum fields are stable and indicate that the Yang-Mills vacuum is highly degenerate quantum state.

    ↳ hep-thgr-qchep-phNPB(2023)·12 citations
47. 47*

    Shifts in BCFW method for QED

    Ke Li🇺🇸 · Yuxin Liu🇨🇳 · Qi-Shu Yan🇨🇳 · Xiaoran Zhao🇮🇹

    We study the application of BCFW recursion relations to the QED processes $0\to e^{-}{e}^{+}n\gamma$. Based on 6-point amplitudes (both MHVA and NMHVA) computed from Feynman diagrams in the Berends-Giele gauge, we conduct a comprehensive study on all different shifts. Then we propose a new shift (LLYZ shift) which can lead to the full amplitudes for these processes and can have some realistic computation advantages. We compare the number of terms and the independent amplitudes of this novel shift with a few typical shifts.

    ↳ hep-thhep-phCPC(2022)·0 citations
48. 48*

    New Horizons: Scalar and Vector Ultralight Dark Matter

    D. Antypas🇩🇪 · A. Banerjee🇮🇱 · C. Bartram🇺🇸 · M. Baryakhtar🇺🇸 · J. Betz🇺🇸 · J. J. Bollinger🇺🇸 · C. Boutan🇺🇸 · D. Bowring🇺🇸 · D. Budker🇩🇪 · D. Carney🇺🇸 · G. Carosi🇺🇸 · S. Chaudhuri🇺🇸 and 117 other authors

    The last decade has seen unprecedented effort in dark matter model building at all mass scales coupled with the design of numerous new detection strategies. Transformative advances in quantum technologies have led to a plethora of new high-precision quantum sensors and dark matter detection strategies for ultralight ($<10$eV) bosonic dark matter that can be described by an oscillating classical, largely coherent field. This white paper focuses on searches for wavelike scalar and vector dark matter candidates.

    ↳ hep-exastro-ph.COhep-phphysics.ins-det+1267 citations
49. 49*

    Axion Dark Matter

    C. B. Adams🇩🇪 · N. Aggarwal🇺🇸 · A. Agrawal🇺🇸 · R. Balafendiev · C. Bartram🇺🇸 · M. Baryakhtar🇺🇸 · H. Bekker🇩🇪 · P. Belov · K. K. Berggren🇺🇸 · A. Berlin🇺🇸 · C. Boutan🇺🇸 · D. Bowring🇺🇸 and 143 other authors

    Axions are well-motivated dark matter candidates with simple cosmological production mechanisms. They were originally introduced to solve the strong CP problem, but also arise in a wide range of extensions to the Standard Model. This Snowmass white paper summarizes axion phenomenology and outlines next-generation laboratory experiments proposed to detect axion dark matter. There are vibrant synergies with astrophysical searches and advances in instrumentation including quantum-enabled readout, high-Q resonators and cavities and large high-field magnets. This white paper outlines a clear roadmap to discovery, and shows that the US is well-positioned to be at the forefront of the search for axion dark matter in the coming decade.

    ↳ hep-exastro-ph.COhep-phphysics.ins-det361 citations
50. 50*

    On the Sound Speed in Neutron Stars

    Sinan Altiparmak🇩🇪 · Christian Ecker🇩🇪 · Luciano Rezzolla🇩🇪

    Determining the sound speed $c_s$ in compact stars is an important open question with numerous implications on the behaviour of matter at large densities and hence on gravitational-wave emission from neutron stars. To this scope, we construct more than $10^7$ equations of state (EOSs) with continuous sound speed and build more than $10^8$ nonrotating stellar models consistent not only with nuclear theory and perturbative QCD, but also with astronomical observations. In this way, we find that EOSs with sub-conformal sound speeds, i.e. with $c_s^2<1/3$ within the stars, are possible in principle but very unlikely in practice, being only $0.03\%$ of our sample. Hence, it is natural to expect that $c_s^2>1/3$ somewhere in the stellar interior. Using our large sample, we obtain estimates at $95\%$ credibility of neutron-star radii for representative stars with $1.4$ and $2.0$ solar masses, $R_{1.4}=12.42_{-0.99}^{+0.52}\mathrm{km}$, $R_{2.0}=12.12_{-1.23}^{+1.11}\mathrm{km}$, and for the binary tidal deformability of the GW170817 event, ${\tilde{\Lambda }}_{1.186}=485_{-211}^{+225}$. Interestingly, our lower-bounds on the radii are in very good agreement with the prediction derived from very different arguments, namely, the threshold mass. Finally, we provide simple analytic expressions to determine the minimum and maximum values of $\tilde{\Lambda }$ as a function of the chirp mass.

    ↳ astro-ph.HEgr-qchep-phnucl-thApJL(2022)·266 citations
51. 51*

    Semi-classical kinetic theory for massive spin-half fermions with leading-order spin effects

    Arpan Das🇵🇱 · Wojciech Florkowski🇵🇱 · Avdhesh Kumar🇹🇼 · Radoslaw Ryblewski🇵🇱 · Rajeev Singh🇵🇱

    We consider the quantum kinetic-theory description for interacting massive spin-half fermions using the Wigner function formalism. We derive a general kinetic theory description assuming that the spin effects appear at the classical and quantum level. To track the effect of such different contributions we use the semi-classical expansion method to obtain the generalized dynamical equations including spin, analogous to classical Boltzmann equation. This approach can be used to obtain a collision kernel involving local as well as non-local collisions among the microscopic constituent of the system and eventually, a framework of spin hydrodynamics ensuring the conservation of the energy-momentum tensor and total angular momentum tensor.

    ↳ hep-thhep-phnucl-thActa Phys.Polon.B(2023)·22 citations
52. 52*

    No scalar condensations outside reflecting stars with coupling terms from Ginzburg-Landau models

    Guohua Liu🇨🇳 · Yan Peng🇨🇳

    We consider static scalar fields coupled to the gradient where the coupling also appears in next-to-leading order Ginzburg-Landau models. We study condensation behaviors of scalar fields outside regular compact reflecting stars in the asymptotically flat background. For non-negative coupling parameters, we prove that the reflecting star cannot support coupled static scalar fields.

    ↳ gr-qchep-phNPB(2022)·1 citation

* 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.