Wed·Oct 18, 2023Wednesday·October 18, 2023

1. 01*

   On running coupling in the JIMWLK evolution and its Langevin formulation

   Tolga Altinoluk🇵🇱 · Guillaume Beuf🇵🇱 · Michael Lublinsky🇮🇱 · Vladimir V. Skokov🇺🇸

   Various conventional running coupling prescriptions reproducing ${\beta }_0$-dependent terms of NLO JIMWLK are reviewed and found to be theoretically inconsistent: the JIMWLK evolution Hamiltonian with running coupling violates the requirement of positive semidefiniteness. This requirement appears to be tightly related to the possibility of having a Langevin formulation for the evolution. We also review the scheme that attributes a part of ${\beta }_0$-dependent terms to the DGLAP evolution of the projectile. The remaining ${\beta }_0$-dependent contributions sum up into so-called the ``daughter dipole'' prescription, which leads to a manifestly positive semidefinite Hamiltonian.

   hep-phJHEP(2024)·7 citations
2. 02*

   On Dark Matter Self-interaction via Single Neutrino Exchange Potential

   Yue Zhang🇨🇦

   Neutrinos -- amongst the lightest known particles -- can mediate a force driving dark matter self-interaction and the small scale structure of the universe. We explore such a possibility in the simplest neutrino portal dark sector model where neutrino has a Yukawa coupling with a scalar $\varphi$ and fermion $\chi$ that are degenerate in mass and together comprise 100\% of dark matter in the universe. We derive the non-relativistic potential generated by single-neutrino exchange which is of the monopole-dipole form and explore $\chi \varphi \to \chi \varphi$ scattering based on phase shift analysis. Our result shows that Born approximation continues to be valid in the low energy regime and the scattering cross section scales as $1/v^2$ over a wide range of dark matter velocities. Such a velocity-dependent self-interacting cross section can be large enough to explain the shallow density of dwarf galaxy cores and consistent with the upper limit from colliding galaxy clusters. The $1/v^2$ behavior persists down to rather low velocities $v\sim m_{\nu }/m$ where $m$ is the dark matter mass, leaving the opportunity for further astrophysical probes. Through the neutrino portal, the self-interacting dark matter parameter space can be tested by searches for $Z$-boson and light mesons decaying into the dark sector, as well as low-mass dark matter direct detection experiments.

   hep-phastro-ph.COPhys.Dark Univ.(2024)·4 citations
3. 03*

   Boosted Top Tagging through Flavour-violating interactions at the LHC

   Shreecheta Chowdhury🇮🇳 · Amit Chakraborty🇮🇳 · Saunak Dutta🇮🇳

   This paper describes a method for detecting a rare top quark decay into a charm quark and a Higgs boson (H), which decays further into b quarks, at the Large Hadron Collider (LHC), and introduces a tagging algorithm to identify boosted tops using large-R jets containing b- and c-tagged elements. We consider the associated production of the top quark with a W-boson and identify different observables to discriminate the signal from the Standard Model (SM) background events. Although our model with improved jet substructure methods outperforms existing approaches to tag such rare decay tops, the improvement in the New Physics reach in terms of $t\to cH$ branching ratio is marginal, even at the high luminosity run of LHC, compared to the existing limits from the LHC 13 TeV data. Although the result seems negative from the point of view of BSM reach, it is significant enough to motivate further studies in the search for the rare top decays at future colliders with higher energy and luminosity. Additionally, the paper utilizes SHAP, a Game Theory-based method, to analyze the contribution of each observable to the classification of events, offering valuable insights into the classifier. The approach presented in this paper is robust in scope and can be effectively implemented for similar probes of physics beyond the SM.

   hep-phhep-exEPJC(2025)·6 citations
4. 04*

   Multi-dimensional hadron structure through the lens of gluon Wigner distribution

   Roman Pasechnik🇸🇪 · Marek Taševský🇨🇿

   In this review, we present the current status of phenomenological research on constraining the multi-dimensional proton (and nucleus) structure at high energies through studies of the so-called gluon Wigner distributions. We provide a brief pedagogical introduction into the corresponding theoretical definitions and modelling of exclusive and diffractive scattering observables in terms of the Wigner distribution. Also, we present a detailed outlook into the existing and planned experimental measurements that attempt to constrain the Wigner distribution. We briefly overview possible interconnections between various manifestations of the gluon Wigner distribution emerging, for instance, in azimuthal-angle correlations in (semi)exclusive reactions and elliptic flow measurements in inclusive processes. We also summarise the current knowledge on the most important processes that would potentially enable one to constrain the elliptic gluon density in the proton and to separate it from the genuine effect of hydrodynamic evolution in the flow measurements.

   hep-phnucl-thPhys.Rept.(2024)·17 citations
5. 05*

   Winos from natural SUSY at the high luminosity LHC

   Howard Baer🇺🇸 · Vernon Barger🇺🇸 · Xerxes Tata🇺🇸 · Kairui Zhang🇺🇸

   In natural supersymmetric models defined by no worse than a part in thirty electroweak fine-tuning, winos and binos are generically expected to be much heavier than higgsinos. Moreover, the splitting between the higgsinos is expected to be small, so that the visible decay products of the heavier higgsinos are soft, rendering the higgsinos quasi-invisible at the LHC. Within the natural SUSY framwork, heavy electroweak gauginos decay to W, Z or h bosons plus higgsinos in the ratio ~2:1:1, respectively. This is in sharp contrast to models with a bino-like lightest superpartner and very heavy higgsinos, where the charged (neutral) wino essentially always decays to a W (h) boson and an invisible bino. Wino pair production at the LHC, in natural SUSY, thus leads to VV, Vh and hh+MET final states (V=W, Z) where, for TeV scale winos, the vector bosons and h daughters are considerably boosted. We identify eight different channels arising from the leptonic and hadronic decays of the vector bosons and the decay h-> b\bar{b}, each of which offers an avenue for wino discovery at the high luminosity LHC (HL-LHC). By combining the signal in all eight channels we find, assuming \sqrt{s}=14 TeV and an integrated luminosity of 3000 fb^{-1}, that the discovery reach for winos extends to m(wino)~1.1~TeV, while the 95% CL exclusion range extends to a wino mass of almost 1.4~TeV. We also identify ``higgsino specific channels'' which could serve to provide 3\sigma evidence that winos lighter than 1.2~TeV decay to light higgsinos rather than to a bino-like LSP, should a wino signal appear at the HL-LHC.

   hep-phPRD(2024)·13 citations
6. 06*

   Quantum tomography of helicity states for general scattering processes

   Alexander Bernal🇪🇸

   Quantum tomography has become an indispensable tool in order to compute the density matrix $\rho$ of quantum systems in Physics. Recently, it has further gained importance as a basic step to test entanglement and violation of Bell inequalities in High-Energy Particle Physics. In this work, we present the theoretical framework for reconstructing the helicity quantum initial state of a general scattering process. In particular, we perform an expansion of $\rho$ over the irreducible tensor operators $\{T_M^L\}$ and compute the corresponding coefficients uniquely by averaging, under properly chosen Wigner D-matrices weights, the angular distribution data of the final particles. Besides, we provide the explicit angular dependence of both the normalised differential cross section and the generalised production matrix $\Gamma$. Finally, we re-derive all our previous results from a quantum-information perspective using the Weyl-Wigner-Moyal formalism and we obtain in addition simple analytical expressions for the Wigner $P$ and $Q$ symbols.

   hep-phhep-thquant-phPRD(2024)·31 citations
7. 07*

   CP-violating top-Higgs coupling in SMEFT

   Vernon Barger🇺🇸 · Kaoru Hagiwara🇯🇵 · Ya-Juan Zheng🇯🇵

   The total cross section of the process ${\mu }^{-}{\mu }^{+}\to {\nu }_{\mu }{\bar{\nu }}_{\mu }t\bar{t}H$ has strong dependence on the CP phase $\xi$ of the top Yukawa coupling, where the ratio of $\xi =\pi$ and $\xi =0$ (SM) grows to 670 at $\sqrt{s}$ = 30 TeV, 3400 at 100 TeV. We study the cause of the strong energy dependence and identify its origin as the $(E/m_W^{}{)}^2$ growth of the weak boson fusion sub-amplitudes, $W_L^{-}{W}_L^{+}\to t\bar{t}H$, with the two $W$s are longitudinally polarized. We repeat the study in the SMEFT framework where EW gauge invariance is manifest and find that the highest energy cross section is reduced to a quarter of the complex top Yukawa model result, with the same energy power. By applying the Goldstone boson (GB) equivalence theorem, we identify the origin of this strong energy growth of the SMEFT amplitudes as associated with the dimension-6 ${\pi }^{-}{\pi }^{+}ttH$ vertex, where ${\pi }^{\pm }$ denotes the GB of $W^{\pm }$. We obtain the unitarity bound on the coefficient of the SMEFT operator by studying all $2\to 2$ and $2\to 3$ cross sections in the $J=0$ channel.

   hep-phPLB(2024)·15 citations
8. 08*

   Dissipative Effects as New Observables for Cosmological Phase Transitions

   Huai-Ke Guo🇨🇳

   We show that dissipative effects during cosmological first order phase transitions lead to a frequency-dependent suppression for the usually dominant gravitational wave production from sound waves, through an analytical modelling of the source based on the sound shell model. This damping effect is more pronounced for high frequencies or small scales, and modifies the spectral shape and possibly the peak frequency. These modifications can be used to reveal more information about the underlying particle interactions, serving as a way of breaking the parameter degeneracy that plagues particle physics studies based on the perfect fluid approximation.

   hep-ph6 citations
9. 09*

   Aiming for Tops of ALPs with a Muon Collider

   So Chigusa🇺🇸 · Sudhakantha Girmohanta🇨🇳 · Yuichiro Nakai🇨🇳 · Yufei Zhang🇨🇳

   Future muon colliders with center-of-mass energy of $\mathcal{O}(1-10)$ TeV can provide a clean high-energy environment with advantages in searches for TeV-scale axion-like particles (ALPs), pseudo-Nambu-Goldstone bosons associated with spontaneously broken global symmetries, which are widely predicted in physics beyond the Standard Model (SM). We exploit ALP couplings to SM fermions, and guided by unitarity constraints, build a search strategy focusing on the ALP decay to top quark pairs at muon colliders. It is found that a large parameter space of TeV-scale ALPs with TeV-scale decay constants can be probed by utilizing the ALP-top quark coupling.

   hep-phhep-exJHEP(2024)·13 citations
10. 10*

    Revisiting Renormalization Group Equations of the SMEFT Dimension-Seven Operators

    Di Zhang🇩🇪

    In this work, we revisit the renormalization group equations (RGEs) of dimension-seven (dim-7) operators in the Standard Model effective field theory (SMEFT) resulting from mixing among dim-7 operators themselves by means of the background field method. Adopting a recently proposed physical basis for dim-7 operators, we achieve the explicit RGEs of all non-redundant dim-7 operators in the SMEFT for the first time. Together with those originating from the dim-5 and dim-6 operators, these results constitute the complete RGEs of dim-7 operators, and hence can be exploited to study full RG-running effects on some lepton- or baryon-number-violating processes involving dim-7 operators in the SMEFT, such as neutrino masses, neutrinoless double beta decay, meson and nucleon decays. We perform an analysis of the structure and perturbative power counting of the obtained one-loop anomalous dimension matrix, which is consistent with a non-renormalization theorem and the naive dimension analysis. Additionally, a partial check on some results is carried out by means of different tools and quantum field gauges.

    hep-phhep-exJHEP(2024)·21 citations
11. 11*

    Diffractive single hadron production in a saturation framework at the NLO

    Michael Fucilla🇫🇷 · Andrey Grabovsky🇷🇺 · Emilie Li🇫🇷 · Lech Szymanowski🇵🇱 · Samuel Wallon🇫🇷

    We calculate the cross-sections of diffractive single hadron photo- or electroproduction with large $p_T$, on a nucleon or a nucleus in the shockwave formalism. We use the hybrid formalism mixing collinear factorization with high energy small-$x$ factorization with the impact factors computed at next-to-leading order accuracy. We prove the cancellation of divergence and we determine the finite parts of the differential cross-sections. We work in general kinematics such that both photoproduction and leptoproduction are considered. The results can be used to detect saturation effects, at both the future EIC or already at LHC, using Ultra-Peripheral Collisions.

    hep-phhep-exJHEP(2024)·32 citations
12. 12*

    Sommerfeld effect for continuum gamma-ray spectra from Dark Matter annihilation

    Barbara Jäger🇩🇪 · Martin Vollmann🇩🇪

    We present a calculation of the continuum part of the gamma-ray spectra resulting from Dark Matter annihilation in the framework of the MSSM taking into account Sommerfeld effects. Concentrating on pure wino and pure higgsino scenarios we compare our calculation to existing work and explore the numerical impact of the features not captured by previous approximative descriptions. We find that, in particular for large neutralino masses, when the Sommerfeld enhancement is very large, chargino-antichargino annihilation processes, which have not been considered before, lead to sizable differences with respect to existing calculations. In scenarios with neutralinos in the intermediate-mass range, we find that the role of the charginos is crucial in the endpoint regime. Our calculation provides the currently most accurate prediction for the continuum gamma-ray spectra.

    hep-phastro-ph.HEJHEP(2024)·2 citations
13. 13*

    The Gorishny-Isaev vacuum integrations and UV(IR)-regime

    I.V. Anikin🇷🇺

    We present the further development of the vacuum massless integrations. In particular, in the Gorishny-Isaev formula, it has been shown that the delta function representing UV-regime should be treated within the sequential approach. It allows us to resolve the problem of vacuum integrations related to the analytical continuation of diagram indices.

    hep-phhep-thPhys.Part.Nucl.(2024)·1 citation
14. 14*

    Theoretical study of the open-flavor tetraquark $T_{c\bar{s}}(2900)$ in the process ${\Lambda }_b\to K^0{D}^0\Lambda$

    Wen-Tao Lyu🇨🇳 · Yun-He Lyu🇨🇳 · Man-Yu Duan🇨🇳 · Guan-Ying Wang🇨🇳 · Dian-Yong Chen🇨🇳 · En Wang🇨🇳

    Recently, the LHCb Collaboration has measured the processes $B^0\to {\bar{D}}^0{D}_s^{+}{\pi }^{-}$ and $B^{+}\to {\bar{D}}^0{D}_s^{+}{\pi }^{+}$, where the $D_s^{+}{\pi }^{-}$ and $D_s^{+}{\pi }^{+}$ invariant mass distributions show the significant signals of two new open-flavor tetraquark states $T_{c\bar{s}}(2900{)}^0$ and $T_{c\bar{s}}(2900{)}^{++}$, as the two of the isospin triplet. In this work, we have investigated the process ${\Lambda }_b\to K^0{D}^0\Lambda$ by taking into account the intermediate nucleon resonance $N^{\ast }(1535)$ and the tetraquark state $T_{c\bar{s}}(2900{)}^0$, which could be dynamically generated by the interactions of the $D^{\ast }{K}^{\ast }/D_s^{\ast }\rho$ and the pseoduscalar mesons-octet baryons, respectively. Our results show that a clear peak of the open-flavor tetraquark $T_{c\bar{s}}(2900)$ may appear in the $K^0{D}^0$ invariant mass distribution of the process ${\Lambda }_b\to K^0{D}^0\Lambda$, which could be tested by future experiments.

    hep-phEPJC(2025)·19 citations
15. 15*

    Revisiting representations of quark mixing matrix

    Gurjit Kaur🇮🇳 · Aakriti Bagai🇮🇳 · Gulsheen Ahuja🇮🇳 · Manmohan Gupta🇮🇳

    Using unitarity, unlike the approaches available in the literature, we have constructed 9 independent representations of CKM matrix starting with each of the 9 elements of the matrix. The relationship of these independently constructed representations with the already available ones in the literature has been compared and discussed. Further, the implications of these representations have been explored for some of the CKM parameters such as \delta, J and \epsilon_k. Interestingly, we find that the PDG representation which is equivalent to our first representation seems to be most appropriate to incorporate the hierarchy of the elements of the CKM matrix as well as to describe the related phenomenology.

    hep-phPTEP(2024)·4 citations
16. 16*

    Kaon Structure in the Nuclear Medium within the Light Front Approach

    G. H. S. O. Yabusaki (Universidade São Judas Tadeu, Universidade Cruzeiro do Sul and Universidade Cidade de São Paulo, Brazil)🇧🇷 · J. P. B. C. de Melo (Universidade Cruzeiro do Sul and Universidade Cidade de São Paulo, Brazil)🇧🇷 · K. Tsushima (Universidade Cruzeiro do Sul and Universidade Cidade de São Paulo, Brazil)🇧🇷 · T. Frederico (Instituto Tecnológico de Aeronáutica, Brazil)🇧🇷 · W. de Paula (Instituto Tecnológico de Aeronáutica, Brazil)🇧🇷

    We study the properties of the charged kaon in symmetric nuclear matter using a Bethe-Salpeter amplitude to model the quark-anti-quark bound state, which is well constrained by previous studies of its vacuum properties. The electromagnetic form factor, charge radius, decay constant and the light-front valence component probability are investigated in symmetric nuclear matter. In order to describe the constituent up and anti-strange quarks in nuclear matter, we adopt the ``quark-meson coupling (QMC) model", which has been widely applied to various hadronic and nuclear phenomena in the nuclear medium.

    hep-phhep-thnucl-thPRD(2024)·8 citations
17. 17*

    Lepton Flavour Violating {Lambda}_b decays in non-universal Z^' model

    S. Biswas🇮🇳 · P. Nayek🇮🇳 · P. Maji🇮🇳 · S. Sahoo🇮🇳

    Motivated by the recent LHCb results of lepton flavour violation on b decays into s and b decays into c transitions we study the lepton flavour violating (LFV) baryonic decays {Lambda}_b decays into {Lambda}l_i^+ l_j^- in non-universal Z^' model. We discuss the two-fold decay distribution of {Lambda}_b decays into {Lambda}l_i^+ l_j^- decays in terms of transversity amplitudes. From this distribution we study the differential branching ratio and lepton side forward-backward asymmetry in new physics (NP). The predicted values of the observables are very interesting and that might emboss the footprints of NP more aesthetically.

    hep-phEPJC(2021)·6 citations
18. 18*

    Impact of Non-universal Z^' in the Lepton Flavour Violating B(B_s ) to K^* ({\phi}) l_1^- l_2^+ decays

    S. Biswas🇮🇳 · S. Mahata🇮🇳 · A. Biswas🇮🇳 · S. Sahoo🇮🇳

    In recent years, lepton flavour violating (LFV) decays are one of the most trending topics to probe new physics (NP). The latest results of LHCb have motivated us to study the LFV decays through b to s transition. The branching ratios, forward backward asymmetries and longitudinal polarization fractions of B(B_s) to K^* ({phi})l_1 l_2 decays are studied in non-universal Z^' model. Here, we have structured the four-fold angular distribution of the decays in terms of transversity amplitudes. The variation of the observables in whole kinematic region shows the sensitivity of NP. The observables estimated in this work are very intriguing and might lead a new track towards NP in near future.

    hep-phEPJC(2022)·3 citations
19. 19*

    Dark matter scattering off ${}^4$He in chiral effective field theory

    J. de Vries🇳🇱 · C. Körber🇩🇪 · A. Nogga🇩🇪 · S. Shain🇳🇱

    We study dark matter scattering off ${}^4$He and other light nuclei using chiral effective field theory. We consider scalar DM interactions and include both one- and two-nucleon scattering processes. The DM interactions and nuclear wave functions are obtained from chiral effective field theory and we work up to fourth order in the chiral expansion for the latter to investigate the chiral convergence. The results for the scattering rates can be used to determine the sensitivity of planned experiments to detect relatively light dark matter particles using ${}^4$He. We find that next-to-leading-order scalar currents are smaller than expected from power counting for scattering off ${}^4$He confirming earlier work. However, the results for two-nucleon corrections exhibit a linear regulator dependence indicating potential problems in the applied power counting. We observe a linear correlation between the, in principle not observable, D-wave probability of various light nuclei and the scalar two-nucleon matrix elements, again pointing towards potentially missing contributions.

    hep-phnucl-thEPJC(2024)·8 citations
20. 20*

    How to measure the transverse polarization of the produced hadrons in a symmetric collider?

    Zhen-Hua Zhang🇨🇳

    In this paper, some subtleties in the measurement of the transverse polarization of the produced hadrons on symmetric colliders -- such as the Large Hadron Collider when conducting the $pp$ collisions -- are revealed. It can be proved that the transverse polarization of the produced particles with opposite pseudorapidity takes exactly opposite values if the normal vector of the production plane is defined in a convention-dependent way, regardless of whether parity is conserved or not in the production process. The analysis shows that, due to the symmetry of the initial state, the ${\Lambda }_b$ transverse polarization measured by the CMS collaboration in Phys. Rev. D 97, 072010 (2018) should be exactly equal to zero. A modified measurement of the ${\Lambda }_b$ polarization for CMS and ATLAS is proposed, the result of which can be compared to the LHCb measurement.

    hep-phhep-exPRD(2024)·1 citation
21. 21*

    Study of non-standard interaction mediated by a scalar field at ESSnuSB experiment

    ESSnuSB: J. Aguilar · M. Anastasopoulos · E. Baussan · A. K. Bhattacharyya · A. Bignami · M. Blennow · M. Bogomilov · B. Bolling · E. Bouquerel · F. Bramati · A. Branca · W. Brorsson and 78 other authors

    In this paper we study non-standard interactions mediated by a scalar field (SNSI) in the context of ESSnuSB experiment. In particular we study the capability of ESSnuSB to put bounds on the SNSI parameters and also study the impact of SNSI in the measurement of the leptonic CP phase ${\delta }_{\mathrm{CP}}$. Existence of SNSI modifies the neutrino mass matrix and this modification can be expressed in terms of three diagonal real parameters (${\eta }_{ee}$, ${\eta }_{\mu \mu }$ and ${\eta }_{\tau \tau }$) and three off-diagonal complex parameters (${\eta }_{e\mu }$, ${\eta }_{e\tau }$ and ${\eta }_{\mu \tau }$). Our study shows that the upper bounds on the parameters ${\eta }_{\mu \mu }$, ${\eta }_{\tau \tau }$ and ${\eta }_{\mu \tau }$ depend upon how $\Delta m_{31}^2$ is minimized in the theory. However, this is not the case when one tries to measure the impact of SNSI on ${\delta }_{\mathrm{CP}}$. Further, we show that the CP sensitivity of ESSnuSB can be completely lost for certain values of ${\eta }_{ee}$ and ${\eta }_{\mu \tau }$ for which the appearance channel probability becomes independent of ${\delta }_{\mathrm{CP}}$.

    ↳ hep-exhep-phPRD(2024)·26 citations
22. 22*

    Viscosities of the Baryon-Rich Quark-Gluon Plasma from Beam Energy Scan Data

    Chun Shen🇺🇸 · Björn Schenke🇺🇸 · Wenbin Zhao🇺🇸

    This work presents the first Bayesian inference study of the (3+1)D dynamics of relativistic heavy-ion collisions and Quark-Gluon Plasma (QGP) viscosities using an event-by-event (3+1)D hydrodynamics + hadronic transport theoretical framework and data from the Relativistic Heavy Ion Collider (RHIC) Beam Energy Scan program. Robust constraints on initial state nuclear stopping and the baryon chemical potential-dependent shear viscosity of the produced quantum chromodynamic (QCD) matter are obtained. The specific bulk viscosity of the QCD matter is found to exhibit a preferred maximum around $\sqrt{s_{\mathrm{NN}}}=19.6$ GeV. This result allows for the alternative interpretation of a reduction (and/or increase) of the speed of sound relative to that of the employed lattice-QCD based equation of state (EOS) for net baryon chemical potential ${\mu }_B\sim 0.2(0.4)$ GeV.

    ↳ nucl-thhep-phnucl-exPRL(2024)·42 citations
23. 23*

    Primordial non-Gaussianity as a saviour for PBH overproduction in SIGWs generated by Pulsar Timing Arrays for Galileon inflation

    Sayantan Choudhury🇮🇳 · Kritartha Dey🇮🇳 · Ahaskar Karde🇮🇳 · Sudhakar Panda🇮🇳 · M. Sami🇮🇳

    We investigate the explicit role of negative local non-Gaussianity, $f_{\mathrm{NL}}$, in suppressing the abundance of primordial black holes (PBHs) in the single-field model of Galileon inflation. PBH formation requires significantly enhancing the scalar power spectrum, which greatly affects their abundance. The associated frequencies in the nHz regime are also sensitive to the generation of scalar-induced gravitational waves (SIGWs) which may explain the current data from the pulsar timing arrays (PTAs). Our analysis using the threshold statistics on the compaction function demonstrates that Galileon theory not only avoids PBH overproduction using the curvature perturbation enhancements that give $f_{\mathrm{NL}}\sim \mathcal{O}(-6)$, but also generates SIGWs that conform well with the PTA data.

    ↳ astro-ph.COgr-qchep-phhep-thPLB(2024)·72 citations
24. 24*

    $R$-dependence of jet observables with JEWEL+v-USPhydro

    Leonardo Barreto🇧🇷 · Fabio M. Canedo🇧🇷 · Maria M. M. Paulino🇧🇷 · Jacquelyn Noronha-Hostler🇺🇸 · Jorge Noronha🇺🇸 · Marcelo G. Munhoz🇧🇷

    The $R$-dependence of jet observables provides a new tool in understanding the interplay between the jet energy-loss mechanism and medium response in heavy-ion collisions. This work applies the Monte Carlo events generator JEWEL and PYTHIA, coupled with ${\mathrm{T}}_{\mathrm{R}}\mathrm{ENTo}$ initial conditions and the state-of-the-art (2+1)D v-USPhydro, for the simulation of jet distributions and substructure observables for lead-lead collisions at LHC energy scales. We present the jet nuclear modification $R_{AA}$ and anisotropic flow coefficients $v_{n=2,3}$ varying the jet cone radius $R$, in the context of anti-$k_T$ jets, in addition to leading subjet fragmentation. The calculations indicate the impacts of the hydrodynamic evolution and weakly-coupled medium response, given by recoils, on the distributions. Results are compared to experimental data in a wide range of jet $p_T$ and collision centrality, and displayed along large jets ($R\ge 0.6$) predictions.

    ↳ nucl-thhep-phPoS(2024)·0 citations
25. 25*

    Limitations of entanglement entropy in detecting thermal phase transitions

    Niko Jokela🇫🇮 · Helime Ruotsalainen🇫🇮 · Javier G. Subils🇸🇪

    We explore the efficacy of entanglement entropy as a tool for detecting thermal phase transitions in a family of gauge theories described holographically. The rich phase diagram of these theories encompasses first and second-order phase transitions, as well as a critical and a triple point. While entanglement measures demonstrate some success in probing transitions between plasma phases, they prove inadequate when applied to phase transitions leading to gapped phases. Nonetheless, entanglement measures excel in accurately determining the critical exponent associated with the observed phase transitions, providing valuable insight into the critical behavior of these systems.

    ↳ hep-thhep-phquant-phJHEP(2024)·10 citations
26. 26*

    Search for Non-Tensorial Gravitational-Wave Backgrounds in the NANOGrav 15-Year Data Set

    Zu-Cheng Chen🇨🇳 · Yu-Mei Wu🇨🇳 · Yan-Chen Bi🇨🇳 · Qing-Guo Huang🇨🇳

    The recent detection of a stochastic signal in the NANOGrav 15-year data set has aroused great interest in uncovering its origin. However, the evidence for the Hellings-Downs correlations, a key signature of the gravitational-wave background (GWB) predicted by general relativity, remains inconclusive. In this letter, we search for an isotropic non-tensorial GWB, allowed by general metric theories of gravity, in the NANOGrav 15-year data set. Our analysis reveals a Bayes factor of approximately 2.5, comparing the quadrupolar (tensor transverse, TT) correlations to the scalar transverse (ST) correlations, suggesting that the ST correlations provide a comparable explanation for the observed stochastic signal in the NANOGrav data. We obtain the median and the $90\%$ equal-tail amplitudes as ${\mathcal{A}}_{\mathrm{ST}}=7.8_{-3.5}^{+5.1}\times 10^{-15}$ at the frequency of 1/year. Furthermore, we find that the vector longitudinal (VL) and scalar longitudinal (SL) correlations are weakly and strongly disfavoured by data, respectively, yielding upper limits on the amplitudes: ${\mathcal{A}}_{\mathrm{VL}}^{95\%}\lesssim 1.7\times 10^{-15}$ and ${\mathcal{A}}_{\mathrm{SL}}^{95\%}\lesssim 7.4\times 10^{-17}$. Lastly, we fit the NANOGrav data with the general transverse (GT) correlations parameterized by a free parameter $\alpha$. Our analysis yields $\alpha =1.74_{-1.41}^{+1.18}$, thus excluding both the TT ($\alpha =3$) and ST ($\alpha =0$) models at the $90\%$ confidence level.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2024)·43 citations
27. 27*

    Effective Theory Approach for Axion Wormholes

    Dhong Yeon Cheong🇰🇷 · Seong Chan Park🇰🇷 · Chang Sub Shin🇰🇷

    We employ the effective field theory approach to analyze the characteristics of Euclidean wormholes within axion theories. Using this approach, we obtain non-perturbative instantons in various complex scalar models with and without a non-minimal coupling to gravity, as well as models featuring the $R^2$ term for a range of coupling values. This yields a series of analytical expressions for the axion wormhole action, shedding light on the model parameters and field dependencies of contributions in both the ultraviolet and infrared domains. Consequently, model-dependent local operators that disrupt axion shift symmetries are generated at lower energy levels. This, in turn, provides crucial insights into the gravitational influences on the axion quality problem.

    ↳ hep-thastro-ph.HEhep-phJHEP(2024)·13 citations
28. 28*

    Diffractive and photon-induced production of top quark

    Michael Pitt🇮🇱

    The top quark plays a central role in particle physics, as many experiments at the Large Hadron Collider scrutinize its properties within the Standard Model. Although most of the measurements of the top quarks today concentrate on production modes initiated by quarks or gluons, this review will highlight the lesser-explored modes initiated by pomerons or photons. It aims to provide an in-depth look into both the phenomenological studies and the existing experimental measurements, emphasizing the necessity of exploring the diffractive and photon-induced production of top quarks to enhance the accuracy of top-quark measurements.

    ↳ hep-exhep-phUniverse(2023)·1 citation
29. 29*

    QUEST-DMC superfluid ${}^3$He detector for sub-GeV dark matter

    S. Autti🇬🇧 · A. Casey🇬🇧 · N. Eng🇬🇧 · N. Darvishi🇬🇧 · P. Franchini🇬🇧 · R. P. Haley🇬🇧 · P.J. Heikkinen🇬🇧 · A. Jennings🇯🇵 · A. Kemp🇬🇧 · E. Leason🇬🇧 · L.V. Levitin🇬🇧 · J. Monroe🇬🇧 and 13 other authors

    The focus of dark matter searches to date has been on Weakly Interacting Massive Particles (WIMPs) in the GeV/$c^2$-TeV/$c^2$ mass range. The direct, indirect and collider searches in this mass range have been extensive but ultimately unsuccessful, providing a strong motivation for widening the search outside this range. Here we describe a new concept for a dark matter experiment, employing superfluid ${}^3$He as a detector for dark matter that is close to the mass of the proton, of order 1 GeV/$c^2$. The QUEST-DMC detector concept is based on quasiparticle detection in a bolometer cell by a nanomechanical resonator. In this paper we develop the energy measurement methodology and detector response model, simulate candidate dark matter signals and expected background interactions, and calculate the sensitivity of such a detector. We project that such a detector can reach sub-eV nuclear recoil energy threshold, opening up new windows on the parameter space of both spin-dependent and spin-independent interactions of light dark matter candidates.

    ↳ hep-exastro-ph.COcond-mat.otherhep-phEPJC(2024)·25 citations
30. 30*

    Constraints on Axion-like Particles from the Observation of GRB 221009A by LHAASO

    Lin-Qing Gao🇨🇳 · Xiao-Jun Bi🇨🇳 · Jun Li🇨🇳 · Run-Min Yao🇨🇳 · Peng-Fei Yin🇨🇳

    The LHAASO collaboration recently reported the measurement of the gamma-ray spectra of GRB 221009A, which is the brightest burst ever, covering an energy range from 0.3 $\mathrm{TeV}$ to about 10 $\mathrm{TeV}$. Based on the observation, we investigate the ALP-photon oscillation effect in the host galaxy of GRB 221009A and the Milky Way. The $\mathrm{C}{\mathrm{L}}_{\mathrm{s}}$ method is applied to set constraints on the ALP parameters in this study. Given the uncertain magnetic field configuration in the host galaxy, we use three different models: a homogeneous magnetic field model, a magnetic field model identical to that of the Milky Way, and a model constructed from the HST observations of the host galaxy. We find that the constraints derived using these three host galaxy magnetic field models are comparable. Our results are complementary in the small ALP mass regions compared with other experiments.

    ↳ astro-ph.HEhep-phJCAP(2024)·22 citations
31. 31*

    Is $K_1/K^{\ast }$ enhancement in heavy ion collisions a signature of chiral symmetry restoration?

    Haesom Sung🇰🇷 · Sungtae Cho🇰🇷 · Che Ming Ko🇺🇸 · Su Houng Lee🇰🇷 · Sanghoon Lim🇰🇷

    We extend the recent study of $K_1/K^{\ast }$ enhancement as a signature of chiral symmetry restoration in heavy ion collisions at the Large Hadron Collider (LHC) via the kinetic approach to include the effects due to non-unity hadron fugacities during the evolution of produced hadronic matter and the temperature-dependent $K_1$ mass. Although the effect of non-unity fugacity only slightly reduces the $K_1/K^{\ast }$ enhancement due to chiral symmetry restoration, the inclusion of the temperature-dependent $K_1$ mass leads to a substantial reduction in the $K_1/K^{\ast }$ enhancement. However, the final $K_1/K^{\ast }$ ratio in peripheral collisions still shows a more than factor of two enhancement compared to the case without chiral symmetry restoration and thus remains a good signature for chiral symmetry restoration in the hot dense matter produced in relativistic heavy ion collisions.

    ↳ nucl-thhep-phPoS(2025)·11 citations
32. 32*

    Dark Energy as a Critical Period in Binary Motion: Bounds from Multi-scale Binaries

    David Benisty🇬🇧 · Jenny Wagner🇮🇱 · Denitsa Staicova🇧🇬

    The two-body problem under the influence of both dark energy and post-Newtonian modifications is studied. In this unified framework, we demonstrate that dark energy plays the role of a critical period with $T_{\Lambda }=2\pi /c\sqrt{\Lambda }\approx 60\text{Gyr}$. We also show that the ratio between orbital and critical period naturally emerges from the Kretschmann scalar, which is a quadratic curvature invariant characterizing all binary systems effectively represented by a de Sitter-Schwarzschild spacetime. The suitability of a binary system to constrain dark energy is determined by the ratio between its Keplerian orbital period $T_{\text{K}}$ and the critical period $T_{\Lambda }$. Systems with $T_{\text{K}}\approx T_{\Lambda }$ are optimal for constraining the cosmological constant $\Lambda$, such as the Local Group and the Virgo Cluster. Systems with $T_{\text{K}}\ll T_{\Lambda }$ are dominated by attractive gravity (which are best suited for studying modified gravity corrections). Systems with $T_{\text{K}}\gg T_{\Lambda }$ are dominated by repulsive dark energy and can thus be used to constrain $\Lambda$ from below. We use our unified framework of post-Newtonian and dark-energy modifications to calculate the precession of bounded and unbounded astrophysical systems and infer constraints on $\Lambda$ from them. Pulsars, the solar system, S stars around Sgr A*, the Local Group, and the Virgo Cluster, having orbital periods of days to gigayears, are analyzed. The results reveal that the upper bound on the cosmological constant decreases when the orbital period of the system increases, emphasizing that $\Lambda$ is a critical period in binary motion.

    ↳ astro-ph.COastro-ph.GAastro-ph.SRgr-qc+1Astron.Astrophys.(2024)·15 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.