In this work, we provide a comprehensive study of fermion-portal dark matter models in the freeze-in regime at a future muon collider. For different possible non-singlet fermion portals, we calculate the upper bound on the mediator's mass arising from the relic abundance calculation and discuss the reach of a future muon collider in probing their viable parameter space in prompt and long-lived particle search strategies. In particular, we develop rudimentary search strategies in the prompt region and show that cuts on the invariant dilepton or dijet masses, the missing transverse mass $M_{T2}$, pseudorapidity and energy of leptons or jets, and the opening angle between the lepton or the jet pair can be employed to subtract the Standard Model background. In the long-lived particle regime, we discuss the signals of each model and calculate their event counts. In this region, the lepton-(quark-)portal model signal consists of charged tracks ($R$-hadrons) that either decay in the detector to give rise to a displaced lepton (jet) signature, or are detector stable and give rise to heavy stable charged track signals. As a byproduct, a pipeline is developed for including the non-trivial parton distribution function of a muon component inside a muon beam; it is shown that this leads to non-trivial effects on the kinematic distributions and attainable significances. We also highlight phenomenological features of all models unique to a muon collider and hope our results, for this motivated and broad class of dark matter models, inform the design of a future muon collider detector. We also speculate on suggestions for improving the sensitivity of a muon collider detector to long-lived particle signals in fermion-portal models.

Probing new physics through precise measurements of Higgs boson couplings is a central objective of the particle collider program at the high-energy frontier. An anomaly in Higgs couplings induced solely by new fermions allows one to compute an upper bound on the mass scale of new bosons. This new bosonic scale is necessary to prevent Landau poles or vacuum instability. Consequently, a single anomalous measurement can provide insight into two distinct new physics scales. In this article, we apply this approach to the loop-induced couplings of the Higgs boson to digluons ($gg$), diphotons ($\gamma \gamma$), and $Z \gamma$, and we compare our results to the projected sensitivities of the HL-LHC and future lepton colliders. This work naturally extends our previous analysis of Higgs couplings to weak dibosons ($WW$ and $ZZ$).

Monopoles are generally expected in Grand Unified Theories (GUTs) where they can catalyze baryon decay at an unsuppressed rate by the Callan-Rubakov effect. For the first time, we show this catalysis effect can generate the observed baryon asymmetry at GeV scale temperatures. We study the minimal SU(5) GUT model and demonstrate that monopoles-fermion scattering with a $CP$-violating $\theta$-term leads to realistic baryogenesis even when $\theta\lesssim 10^{-10}$ is below the neutron EDM bound, potentially detectable in the future measurements. Our calculation also shows that to generate the observed baryon asymmetry, the abundance of the monopoles is below the current experiential bounds.

Dark matter could be a baryonic composite of strongly-coupled constituents transforming under SU(2)$_L$. We classify the SU(2)$_L$ representations of baryons in a class of simple confining dark sectors and find that the lightest state can be a pure singlet or a singlet that mixes with other neutral components of SU(2)$_L$ representations, which strongly suppresses the dark matter candidate's interactions with the Standard Model. We focus on models with a confining $\text{SU}(N_c)$ and heavy dark quarks constituting vector-like $N_f$-plet of SU(2)$_L$. For benchmark $N_c$ and $N_f$, we calculate baryon mass spectra, incorporating electroweak gauge boson exchange in the non-relativistic quark model, and demonstrate that above TeV mass scales, dark matter is dominantly a singlet state. The combination of this singlet nature with the recently discovered $\mathcal{H}$-parity results in an inert state analogous to noble gases, hence we coin the term Noble Dark Matter. Our results can be understood in the non-relativistic effective theory that treats the dark baryons as elementary states, where we find singlets accompanying triplets, 5-plets, or more exotic representations. This generalization of WIMP-like theories is more difficult to find or rule out than dark matter models that include only a single SU(2)$_L$ multiplet (such as a Wino), motivating new searches in colliders and a re-analysis of direct and indirect detection prospects in astrophysical observations.

A Tera-$Z$ factory, such as FCC-ee or CEPC, will have indirect sensitivity to heavy new physics up to the tens of TeV scale through higher-order loop contributions to precision measurements at the $Z$ pole. These indirect quantum effects may provide complementary, or even better, sensitivity to potential deviations from the Standard Model that are typically thought to best be constrained at leading order at higher energies above the $Z$ pole. We show in the SMEFT framework how accuracy complements energy for operators that modify the Higgs and gauge boson two- and three-point functions, leading to improved projected sensitivities for models such as the real singlet scalar, weakly interacting massive particles, and a custodial weak quadruplet. A thorough Tera-$Z$ programme may thus anticipate aspects of physics runs at higher energies and provide a wider scope of quantum exploration of the TeV scale than had previously been appreciated.

We consider leading-colour 2-, 3- and 4-jet rates in hadronic $Z$-boson decay to derive matching conditions at next-to-next-to-leading order in the sectorised VINCIA parton shower. In particular, we present a full subtraction-based calculation of the matching coefficient required to obtain the NLO 3-jet rate. This is achieved through a judicious choice of the counter-terms, which optimises the numerical evaluation of the subtracted double-real matrix element. We additionally give a consistent prescription for incorporating interference effects due to multiple Born states. Finally, we briefly comment on higher-order uncertainty estimates.

We present a model that extends the electroweak gauge symmetry of the Standard Model in a non-universal way to $SU(2)_{L}^{\prime}\times U(1)_X \times SU(2)_{L}^{q_3}\times SU(2)_R^{\ell^3}$. This symmetry is spontaneously broken to $SU(2)_L\times U(1)_Y$ near the TeV scale by a condensate of a new composite sector. Charging appropriately the fermionic degrees of freedom of the composite sector, anomaly cancellation enforces the Standard Model fermions to be charged in such a way that the extended gauge interactions respect a $U(2)_q\times U(2)_e\times U(3)_u\times U(3)_d\times U(3)_\ell$ accidental flavor symmetry. In addition, from the same symmetry breaking, a composite Higgs boson emerges as a pseudo-Nambu-Goldstone boson of the strong dynamics of the new sector. Due to the extended gauge and the specific flavor symmetry, leading Yukawa couplings between Higgs and fermions can only be written for the third generation and higher dimension operators generate suppressed light-family Yukawa couplings. Furthermore, CKM mixing angles between third and light families result naturally suppressed while the PMNS ones, anarchic. The model thus provides a unified origin for the Higgs boson and the flavor hierarchies between third and light families.

We propose a new strategy to obtain a high-purity sample of gluon-initiated jets at the LHC. Our approach, inspired by the Lund jet plane picture, is to perform a dijet selection where the two jets are collinear to each other and their momentum fraction share is highly asymmetric, and to measure the primary Lund plane density of emissions of the subleading jet. The subleading jet in this topology is practically equivalent to a secondary Lund jet plane. We demonstrate by means of fixed-order calculations that such a simple setup yields gluon jet fractions of around 90% for the subleading jet for both quark- and gluon-initiated jets. This observation is confirmed using hadron-level Monte Carlo generated events. We also show that the extracted gluon purities are highly resilient to the overall colour structure of the event, to the flavour of the hard-scattering process, and to the parton distribution functions. This strategy is well-suited for constraining the radiation pattern of gluon-initiated jets using a set of fiducial cuts that can readily be tested at the LHC, without relying on taggers or statistical demixing.

Effective field theories (EFTs) provide an excellent framework for the search of heavy physics beyond the Standard Model, using the so-called bottom-up and top-down approaches. However, the vastness of possible UV scenarios makes the complete connection between the two approaches a difficult challenge at the loop-level. UV/IR dictionaries fill precisely this gap, efficiently connecting the EFT with the UV. In this work we present the complete one-loop dictionary for the Standard Model EFT at dimension six for completions with an arbitrary number of heavy fermions and scalars. Our results (as well as several new functionalities) are added to the previously partial package SOLD. In this new form, SOLD is prepared to serve as an important guiding tool for systematic and complete phenomenological studies. To illustrate this, we use the package to explore possible explanations for the tension on the measurement of $\mathcal{B}(B\rightarrow K \overline{\nu}\nu)$.

Within $Z^\prime$ models, neutral meson mixing severely constrains beyond the Standard Model (SM) effects in flavour changing neutral current (FCNC) processes. However, in certain regions of the $Z^\prime$ parameter space, the contributions to meson mixing observables become negligibly small even for large $Z^\prime$ couplings. While this a priori allows for significant new physics (NP) effects in FCNC decays, we discuss how large $Z^\prime$ couplings in one neutral meson sector can generate effects in meson mixing observables of other neutral mesons, through correlations stemming from $\text{SU(2)}_L$ gauge invariance and through Renormalization Group (RG) effects in the SM Effective Field Theory~(SMEFT). This is illustrated with the example of $B_s^0-\bar B_s^0$ mixing, which in the presence of both left- and right-handed $Z^\prime bs$ couplings $\Delta_L^{bs}$ and $\Delta_R^{bs}$ remains SM-like for $\Delta_R^{bs}\approx 0.1\,\Delta_L^{bs}$. We show that in this case, large $Z^\prime bs$ couplings generate effects in $D$ and $K$ meson mixing observables, but that the $D$ and $K$ mixing constraints and the relation between $\Delta_R^{bs}$ and $\Delta_L^{bs}$ are fully compatible with a lepton flavour universality~(LFU) conserving explanation of the most recent $b\to s\ell^+\ell^-$ experimental data without violating other constraints like $e^+ e^-\to\ell^+\ell^-$ scattering. Assuming LFU, invariance under the $\text{SU(2)}_L$ gauge symmetry leads then to correlated effects in $b\to s\nu\bar\nu$ observables presently studied intensively by the Belle~II experiment, which allow to probe the $Z^\prime$ parameter space that is opened up by the vanishing NP contributions to $B_s^0-\bar B_s^0$ mixing. In this scenario the suppression of $B\to K(K^*)\mu^+\mu^-$ branching ratios implies {\em uniquely} enhancements of $B\to K(K^*)\nu\bar\nu$ branching ratios up to $20\%$.

Deeply inelastic scattering (DIS) is an essential process for exploring the structure of visible matter and testing the standard model. At the same time, the theoretical interpretation of DIS measurements depends on QCD factorization theorems whose validity deteriorates at the lower values of $Q^2$ and $W^2$ typical of neutrino DIS in accelerator-based oscillation searches. For this reason, progress in understanding the origin and limits of QCD factorization is invaluable to the accuracy and precision of predictions for these upcoming neutrino experiments. In these short proceedings, we introduce a novel approach based on the quantum entropy associated with continuous distributions in QCD, using it to characterize the limits of factorization theorems relevant for the description of neutrino DIS. This work suggests an additional avenue for dissecting factorization-breaking dynamics through the quantum entropy, which could also play a role in quantum simulations of related systems.

Cosmologically stable, light particles that came into thermal contact with the Standard Model in the early universe may persist today as a form of hot dark matter. For relics with masses in the eV range, their role in structure formation depends critically on their mass. We trace the evolution of such hot relics and derive their density profiles around cold dark matter halos, introducing a framework for their indirect detection. Applying this framework to axions -- a natural candidate for a particle that can reach thermal equilibrium with the Standard Model in the early universe and capable of decaying into two photons -- we establish stringent limits on the axion-photon coupling $g_{a \gamma} $ using current observations of dwarf galaxies, the Milky Way halo, and galaxy clusters. Our results set new bounds on hot axions in the $\mathcal{O}(1-10)\,$eV range.

Lepton-number-violating interactions occur in the Standard Model Effective Field Theory (SMEFT) at odd dimensions starting from the dimension-5 Weinberg operator. Although the operators at dimension-7 and higher are more suppressed by the heavy new scale, they can be crucial when traditional seesaw mechanisms leading to tree-level dimension-5 contributions are absent. We identify all minimal tree-level UV-completions for dimension-7 $\Delta L=2$ SMEFT operators without covariant derivatives and propose a new simplified approach for estimating the radiative neutrino masses arising from such operators. This dimensional-regularisation-based approach provides a more accurate estimate for the loop neutrino masses when the new physics fields are hierarchical in mass, as compared to the cut-off-regularisation-based approach often employed in the literature. This allows us to identify viable regions of parameter space in the full list of relevant simplified models close to the current limits set by neutrinoless double beta decay and the LHC that would previously have been thought to be excluded by neutrino-mass constraints.

Atom interferometers offer exceptional sensitivity to ultra-light dark matter (ULDM) through their precise measurement of phenomena acting on atoms. While previous work has established their capability to detect scalar and vector ULDM, their potential for detecting spin-2 ULDM remains unexplored. This work investigates the sensitivity of atom interferometers to spin-2 ULDM by considering several frameworks for massive gravity: a Lorentz-invariant Fierz-Pauli case and two Lorentz-violating scenarios. We find that coherent oscillations of the spin-2 ULDM field induce a measurable phase shift through three distinct channels: coupling of the scalar mode to atomic energy levels, and vector and tensor effects that modify the propagation of atoms and light. Atom interferometers uniquely probe all of these effects, while providing sensitivity to a different mass range from laser interferometers. Our results demonstrate the potential of atom interferometers to advance the search for spin-2 dark matter through accessing unexplored parameter space and uncovering new interactions between ULDM and atoms.

We examine nonrenormalizable Lorentz- and CPT-violating effective operators applied to the quark sector of the Standard Model. Using Drell-Yan events collected by the ATLAS and CMS Collaborations, several constraints are extracted from time-independent modifications of the cross section on the $Z$-boson pole. The sensitivity to time-dependent modifications are also estimated by simulating a sidereal-time analysis. Our results suggest a dedicated search can improve on constraints from deep inelastic scattering by up to three orders in magnitude.

Dark matter captured in stars can act as an additional heat transport mechanism, modifying fusion rates and asteroseismoloigcal observables. Calculations of heat transport rates rely on approximate solutions to the Boltzmann equation, which have never been verified in realistic stars. Here, we simulate heat transport in the Sun, the Earth, and a brown dwarf model, using realistic radial temperature, density, composition and gravitational potential profiles. We show that the formalism developed in arXiv:2111.06895 remains accurate across all celestial objects considered, across a wide range of kinematic regimes, for both spin-dependent and spin-independent interactions where scattering with multiple species becomes important. We further investigate evaporation rates of dark matter from the Sun, finding that previous calculations appear robust. Our Monte Carlo simulation software Cosmion is publicly available.

We describe the fits of the top-quark mass value at NNLO using as input the double-differential distributions in rapidity and invariant mass of $t\bar{t}$ pairs obtained by the ATLAS and CMS collaborations from unfolding of their experimental data to the parton level, compared to NNLO theory predictions. We consider different state-of-the-art PDF sets, finding results of the fits compatible among each other within uncertainties. On the other hand, we observe some tension among the fits to different datasets.

Computations with tensors are ubiquitous in fundamental physics, and so is the usage of Einstein's dummy index convention for the contraction of indices. For instance, $T_{ia}U_{aj}$ is readily recognized as the same as $T_{ib}U_{bj}$, but a computer does not know that T[i,a]U[a,j] is equal to T[i,b]U[b,j]. Furthermore, tensors may have symmetries which can be used to simply expressions: if $U_{ij}$ is antisymmetric, then $\alpha T_{ia}U_{aj}+\beta T_{ib}U_{jb}=\left(\alpha-\beta\right)T_{ia}U_{aj}$. The fact that tensors can have elaborate symmetries, together with the problem of dummy indices, makes it complicated to simplify polynomial expressions with tensors. In this work I will present an algorithm for doing so, which was implemented in the Mathematica package SimTeEx (Simplify Tensor Expressions). It can handle any kind of tensor symmetry.

Searches for high frequency gravitational waves using cavities based on the Gertsenshtein effect were recently proposed, building off existing axion dark matter experiments. In particular, the sensitivity of axion dark matter experiments using metamaterial plasmas (tunable plasma haloscopes) to gravitational waves has not been explored in detail. Here we perform a full analysis of gravitational wave detection in plasma haloscopes, showing that the baseline design of experiments such as ALPHA is several orders of magnitude less sensitive than previously thought. We show how simple changes to the experiment can recover that sensitivity and lead to a powerful gravitational wave detector in the order of $(10-50)$ GHz frequency range.

The ATLAS collaboration, using 139 fb$^{-1}$ of 13 TeV collisions from the Large Hadron Collider, has placed limits on the decay of a $Z$ boson to three dark photons. We reproduce the results of the ATLAS analysis, and then recast it as a limit on a exotic Higgs decay mode, in which the Higgs boson decays via a pair of intermediate (pseudo)scalars $a$ to four dark photons $V$ (or some other spin-one meson). Across the mass range for $m_a$ and $m_V$, we find limits on the exotic Higgs branching fraction BR$(H\to aa \to VVVV)$ in the range of $4\times 10^{-5}$ to $1 \times 10^{-4}$.

A new dark matter candidate is proposed that arises as the lightest baryon from a confining $SU(N)$ gauge theory which equilibrates with the Standard Model only through electroweak interactions. Surprisingly, this candidate can be as light as a few GeV. The lower bound arises from the intersection of two competing requirements: i) the equilibration sector of the model must be sufficiently heavy, at least several TeV, to avoid bounds from colliders, and ii) the lightest dark meson (that may be the dark $\eta'$, $\sigma$, or the lightest glueball) has suppressed interactions with the SM, and must decay before BBN. The low energy dark sector consists of one flavor that is electrically neutral and an almost electroweak singlet. The dark matter candidate is the lightest baryon consisting of $N$ of these light flavors leading to a highly suppressed elastic scattering rate with the SM. The equilibration sector consists of vector-like dark quarks that transform under the electroweak group, ensuring that the dark sector can reach thermal equilibrium with the SM in the early Universe. The lightest dark meson lifetimes vary between $10^{-3} \lesssim c \tau \lesssim 10^7$~meters, providing an outstanding target for LHC production and experimental detection. We delineate the interplay between the lifetime of the light mesons, the suppressed direct detection cross section of the lightest baryon, and the scale of equilibration sector that can be probed at the LHC.

Evidences of vortical effects have been recently found by experiments in heavy ion collisions, instigating new insights into the phase diagram of quantum chromodynamics. Considering the effect of rotations, lattice QCD data shows that the temperatures for deconfinement and chiral symmetry restoration should increase with real angular velocity, and the dominant effects are related to gluonic degrees of freedom. These findings could be essential for quark models in rotating systems that lack gluonic interactions, which predicts the decreasing of the chiral temperature transition with the angular velocity. To address this issue properly, in this work we apply the two-flavor Nambu--Jona-Lasinio model to explore the phase diagram in a rotating rigid cylinder with constant angular velocity in the mean field approximation. To circumvent the absence of gluons, we propose the application of an effective coupling dependent of the angular velocity, fitted to match the pseudocritical temperature of chiral phase transition in the model through lattice QCD data. Our results indicate that the running coupling induces the enhancement of the chiral condensate as a function of angular velocity, strengthening the breaking of chiral symmetry, an effect previously dubbed as chiral vortical catalysis. For the chiral susceptibility we observe stronger fluctuations around the transition temperature when we consider the running coupling. The phase diagram is affected by these findings shifting the critical end point (CEP) to higher temperatures and chemical potentials.

The main aim of the the Large Hadron Collider (LHC) experiments is to search for exotic particles with masses in the TeV range as predicted by Beyond Standard Model (BSM) theories. However, there is no hint of BSM around TeV scale so far. Hence, it is possible that the exotic particles are heavier and larger centre of mass energy is needed to observe them. Alternatively, the future lepton colliders offer a comparatively cleaner environment than the LHC which is advantageous to detect light exotic particles. Lepton colliders, like the International Linear Collider, provide the opportunity to detect exotic particles at energies below the TeV scale. The Muon Collider, once fully operational, will have the capability to observe exotic particles at and beyond the TeV scale. The search for BSM particles typically assumes a minimal scenario where only one type of BSM particle couples with the Standard Model (SM) sector. But there are theories which involve such interactions of multiple BSM particles. Here I discusses a specific model featuring a fermionic quintuplet and a scalar quartet that interact before decaying into SM particles. This model yields distinctive signatures characterized by high lepton and jet multiplicities, making it a promising candidate for detection at future lepton colliders.

The Zee-Babu model is an economical framework for neutrino mass generation as two-loop quantum corrections. In this work, we present a UV completion of this model by embedding it into an $SU(5)$ unified framework. Interestingly, we find that loop-induced contributions to neutrino masses arising from colored scalars are just as important as those from color-neutral ones. These new states, which are required from gauge coupling unification and neutrino oscillation data to have masses below $\mathcal{O}(10^3)$ TeV, may be accessible to future collider experiments. Additionally, the model can be probed in proton decay searches. Our Markov chain Monte Carlo analysis of model parameters shows a high likelihood of observable $p \rightarrow e^+ \pi^0$ decay signal in the first decade of Hyper-Kamiokande operation. The model predicts a vector-like down-type quark at the TeV scale, utilized for realistic fermion mass generation and gauge coupling unification. The model is UV-complete in the sense that it is a unified theory which is realistic and asymptotically free that can be extrapolated to the Planck scale.

Axion-like particles are a well-motivated candidate for ultralight dark matter. Because dark matter must be non-relativistic, the effects of its scattering with Standard Model particles are negligible and generally go unnoticed. However, due to the large occupation number of ultralight dark matter, the sum of all scatterings leads to a classical field-like interaction with Standard Model particles. In the case of an axion-like particle, this scattering imparts a parity violating effect. If this collective scattering with axion-like particles is inserted into the one-loop quantum electrodynamics diagram, the parity violation imparted by this scattering will convert the anomalous magnetic moment contribution into an electric dipole moment. This contribution is quite large and leads to a prediction inconsistent with precision measurements of the proton and electron electric dipole moments, unless their couplings to the axion-like particles are very weak. As a result, the constraints on the couplings of axion-like particle dark matter to the electron and proton are improved by as much as eleven and six orders of magnitude, respectively.

Neutrinos being massive could undergo non-radiative decay, a property for which the diffuse supernova neutrino background has a unique sensitivity. We extend previous analyses to explore our ability to disentangle predictions for the diffuse supernova neutrino background in presence or absence of neutrino non-radiative two-body decay. In a three-neutrino framework, we give predictions of the corresponding neutrino fluxes and the expected number of events in the Super-Kamiokande+Gadolinium, the Hyper-Kamiokande, the JUNO and the DUNE experiments. In our analysis, we employ supernova simulations from different groups and include current uncertainties from both the evolving core-collapse supernova rate and the fraction of failed supernovae. We perform the first Bayesian analysis to see our ability to disentangle the cases in presence and absence of neutrino decay. To this aim we combine the expected events in inverse beta-decay and the neutrino-argon detection channels. We also discuss neutrino-electron, neutrino-proton and of neutrino-oxygen scattering. Our investigation covers the different possible decay patterns for normal mass ordering, both strongly-hierarchical and quasi-degenerate as well as the inverted neutrino mass ordering.

In this work, the soft rescattering parameters in the $B^\pm\rightarrow \pi^\pm\pi^+\pi^-$ and $B^\pm\rightarrow K^\pm\pi^+\pi^-$ decays with the light scalar meson $f_0(500)$ as the intermediate resonance are studied within the QCD factorization. Considering the interference effect between $\rho(770)^0$ and $f_0(500)$, we utilize the experimentally more direct event yields for fitting and get the soft rescattering parameters $|\rho_k^{SP}|=3.29\pm1.01$ and $|\rho_k^{PS}|=2.33\pm0.73$ in $B\rightarrow PS$ and $B\rightarrow SP$ decays ($P$ and $S$ denote pseudoscalar and scalar mesons, respectively), respectively. We also study the branching ratios and $CP$ asymmetries in the decay modes involving other scalar mesons, including $f_0(980)$, $a_0(980)$, $a_0(1450)$ and $K_0^*(1430)$, to test the rationality of the values of $|\rho_k^{SP}|$ and $|\rho_k^{PS}|$. Meanwhile, the wealth of experimental data facilitate the examination of the forward-backward asymmetry induced $CP$ asymmetries (FB-CPAs), and the localized $CP$ asymmetries (LACPs). We investigate these asymmetries resulting from the interference between $\rho(770)^0$ and $f_0(500)$ for $B^\pm\rightarrow \pi^\pm\pi^+\pi^-$ and $B^\pm\rightarrow K^\pm\pi^+\pi^-$ decays when the invariant mass of $\pi^+\pi^-$ locates in the low-energy region $0.445\mathrm{GeV}<m_{\pi\pi}<0.795\mathrm{GeV}$. Our theoretical results of FB-CPAs and LACPs align with the experimental findings. We propose that the interference between $\rho(770)^0$ and $f_0(500)$ can be extended to other beauty and charmed mesons decays.

The accidental baryonic symmetry is expected to be broken and required from the observed matter-antimatter asymmetry. The neutron-antineutron oscillating system is the hallmark of $\Delta \mathcal{B} = 2$ models which have the benefits of not inducing proton decay. We study this system in a framework allowing the most general couplings to understand how a dark matter candidate such as the axion may couple to the oscillation. In particular a Rabi resonance phenomenon occurs, and this effect is unconstrained for Axion Like Particles (ALPs) models. Regarding the QCD axion, its Goldstone nature leads to a robust exclusion of the majority of scenarios allowed.

The calculation of hard scattering amplitudes up to NLO is automated in numerical tools, such as OpenLoops. The LHC and future experiments, however, demand high-precision predictions at NNLO and beyond for a wide range of particle processes. Hence, the development of a fully automated tool for numerical NNLO calculations is an important goal. In order to perform a numerical calculation, we decompose $D$-dimensional two-loop amplitudes into Feynman integrals with four-dimensional numerators and $(D-4)$-dimensional remainders, which contribute to the finite result through the interaction with the poles of Feynman integrals and are reconstructed during the subtraction procedure for these poles from universal rational terms. The integrals with four-dimensional numerators are further decomposed into loop momentum tensor integrals and tensor coefficients. We present the status of OpenLoops with respect to these building blocks. The algorithm for the construction of the tensor coefficients is implemented for QED and QCD corrections to the SM in a fully automated way. Recently, the renormalisation procedure and the reconstruction of the interplay of $(D-4)$-dimensional numerator parts with UV poles through two-loop rational counterterms has been implemented and validated using an in-house library for the reduction of simple tensor integrals.

Within the method of parity-projected QCD sum rules, we study the mass spectra of light hybrid baryons with $I(J^{P})=1/2(1/2^{\pm}), 3/2(1/2^{\pm}), 1/2(3/2^{\pm}), 3/2(3/2^{\pm})$ by constructing the local $qqqg$ interpolating currents. We calculate the correlation functions up to dimension eight condensates at the leading order of $\alpha_{s}$. The stable QCD Lapalce sum rules can be established for the positive-parity $N_{1/2^+}, \Delta_{3/2^+}, \Delta_{1/2^+}$ and negative-parity $N_{1/2^-}, N_{3/2^-}, \Delta_{1/2^-}$ channels to extract their mass spectra. The lowest-lying hybrid baryons are predicted to be the negative-parity $N_{1/2^-}$ state around 2.28 GeV and $\Delta_{1/2^-}$ state around 2.64 GeV. These hybrid baryons mainly decay into conventional baryon plus meson final states. We propose to search for the light hybrid baryons through the $\chi_{cJ}/\Upsilon$ decays via the three-gluon emission mechanism in BESIII and BelleII experiments. Our studies of the light hybrid baryons will be useful for understanding the excited baryon spectrum and the behavior of gluonic degrees of freedom in QCD.

In this article we study the possibility that neutral and charged scalars lighter than the 125 GeV Higgs boson might exist within the framework of the $\mathcal{CP}$-conserving Aligned-two-Higgs-doublet model. Depending on which new scalar (scalars) is (are) light, seven different scenarios may be considered. Using the open-source code HEPfit, which relies on Bayesian statistics, we perform global fits for all seven light-mass scenarios. The constraints arising from vacuum stability, perturbativity, electroweak precision observables, flavour observables, Higgs signal strengths, and direct-detection results at the LEP and the LHC are taken into account. Reinterpreted data from slepton searches are considered too. It turns out that the seven scenarios contain sizeable regions of their parameter space compatible with all current data. Although not included in the global fits, the possible implications of $(g-2)_\mu$ are also addressed.

Calculations truncated at a fixed order in perturbation theory are accompanied by an associated theoretical uncertainty, which encodes the missing higher orders (MHOU). This is typically estimated by a scale variation procedure, which has well-known shortcomings. In this work, we propose a simple prescription to directly encode the missing higher order terms using theory nuisance parameters (TNPs) and estimate the uncertainty by their variation. We study multiple processes relevant for Large Hadron Collider physics at next-to-leading and next-to-next-to-leading order in perturbation theory, obtaining MHOU estimates for differential observables in each case. In cases where scale variations are well-behaved we are able to replicate their effects using TNPs, while we find significant improvement in cases where scale variation typically underestimates the uncertainty.

The $B$-Mesogenesis model explains the matter-antimatter asymmetry and leads to the right amount of dark matter in the Universe. In particular, this model predicts new decay channels of the $b$ quark. We investigate the modification of inclusive $b$-hadron decay rates and of the lifetimes of different $B$ mesons due to these new decay channels and compare our results with available predictions for exclusive $B$ meson decays. We find a small surviving parameter space where the $B$-Mesogenesis model is working and which has not been excluded by experiment. Experimental investigations in the near future should be able to test this remaining parameter space and thus either exclude or confirm the $B$-Mesogenesis model.

We describe the global structure of a particle model with dark matter called G2HDM, which incorporates a dark sector represented by $SU(2)_{H} \times U(1)_{X}\;$. The gauge group of such model is $\tilde{G}=U(1)_{Y} \times SU(2)_{L} \times SU(3)_{C} \times SU(2)_{H} \times U(1)_{X} \;$, with an ambiguity that it may actually be $G= \tilde{G} / {\Gamma} \;$, where $\Gamma$ is a subgroup of its center. We also describe how the electric and magnetic charges depend on $\Gamma$ and the periodicity of theta angles for any choice of $G$. Finally, we describe the minimal charges that arise after electroweak symmetry breaking for any choice of $\Gamma$.

It is a continued open question how there can be an azimuthal anisotropy of high $p_\perp$ particles quantified by a sizable $v_2$ in p+Pb collisions when, at the same time, the nuclear modification factor $R_\text{AA}$ is consistent with unity. We address this puzzle within the framework of the jet quenching model \textsc{Jewel}. In the absence of reliable medium models for small collision systems we use the number of scatterings per parton times the squared Debye mass to characterise the strength of medium modifications. Working with a simple brick medium model we show that, for small systems and not too strong modifications, $R_\text{AA}$ and $v_2$ approximately scale with this quantity. We find that a comparatively large number of scatterings is needed to generate measurable jet quenching. Our results indicate that the $R_\text{AA}$ corresponding to the observed $v_2$ could fall within the experimental uncertainty. Thus, while there is currently no contradiction with the measurements, our results indicate that $v_2$ and $R_\text{AA}$ go hand-in-hand. We also discuss departures from scaling, in particular due to sizable inelastic energy loss.

Despite being neutral particles, neutrinos can acquire non-zero electromagnetic properties from radiative corrections that can be induced by the presence of new physics. Electromagnetic neutrino processes induce spectral distortions in neutrino scattering data, which are especially visible at experiments characterized by low recoil thresholds. We investigate how neutrino electromagnetic properties confront the recent indication of coherent elastic neutrino-nucleus scattering (CE$\nu$NS) from $^8$B solar neutrinos in dark matter direct detection experiments. We focus on three possibilities: neutrino magnetic moments, neutrino electric charges, and the active-sterile transition magnetic moment portal. We analyze recent XENONnT and PandaX-4T data and infer the first \cevns-based constraints on electromagnetic properties using solar $^8$B neutrinos.

Using a symmetry-preserving treatment of a vector $\times$ vector contact interaction (SCI) at nonzero temperature, we compute the screening masses of flavour-SU(3) ground-state $J^P=0^\pm$, $1^\pm$ mesons, and $J^P=1/2^\pm$, $3/2^\pm$ baryons. We find that all correlation channels allowed at $T=0$ persist when the temperature increases, even above the QCD phase transition. The results for mesons qualitatively agree with those obtained from the contemporary lattice-regularised quantum chromodynamics (lQCD) simulations. One of the most remarkable features is that each parity-partner-pair degenerates when $T>T_c$, with $T_c$ being the critical temperature. For each pair, the screening mass of the negative parity meson increases monotonously with temperature. In contrast, the screening mass of the meson with positive parity is almost invariant on the domain $T\lesssim T_c/2$; when $T$ gets close to $T_c$, it decreases but soon increases again and finally degenerates with its parity partner, which signals the restoration of chiral symmetry. We also find that the $T$-dependent behaviours of baryon screening masses are quite similar to those of the mesons. For baryons, the dynamical, nonpointlike diquark correlations play a crucial role in the screening mass evolution. We further calculate the evolution of the fraction of each kind of diquark within baryons respective to temperature. We observe that, at high temperatures, only $J=0$ scalar and pseudoscalar diquark correlations can survive within $J^P=1/2^\pm$ baryons.

We report new constraints and sensitivities to heavy neutral leptons (HNLs) with transition magnetic moments, also known as dipole-portal HNLs. This is accomplished using data from the T2K ND280 near detector in addition to the projected three-year dataset of the upgraded ND280 detector. Dipole-portal HNLs have been extensively studied in the literature and offer a potential explanation for the $4.8\sigma$ MiniBooNE anomaly. To perform our analysis, we simulate HNL decays to $e^+e^-$ pairs in the gaseous time projection chambers of the ND280 detector and its upgrade. Recasting an ND280 search for mass-mixed HNLs, we find that ND280 data places world-leading constraints on dipole-portal HNLs in the 390-743\,{\rm MeV} mass range, disfavoring the region of parameter space favored by the MiniBooNE anomaly. The addition of three years of ND280 upgrade data will be able to disfavor the MiniBooNE solution at the $5 \sigma$ confidence level and extend the world-leading constraints to dipole-portal HNLs in the 148-860\,{\rm MeV} mass range. Our analysis suggests that ND280 data excludes dipole-portal HNLs as a solution to the MiniBooNE excess, motivating a dedicated search within the T2K collaboration and potentially highlighting the need for alternative explanations for the MiniBooNE anomaly.

In this work, we introduce the minimal set of leptoquarks into the 3-3-1 model with right-handed neutrinos, capable of generating radiative masses for active neutrinos. As a main consequence, the standard neutrinos acquire small Majorana masses at the one-loop level, while right-handed (sterile) neutrinos obtain small Majorana masses at the two-loop level, naturally making them light particles as well. Additionally, we discuss the viability of this scenario and several other interesting phenomenological consequences, including its impact on $B$-meson physics and rare Higgs decays, both of which are also induced by the leptoquarks.

We perform a model-independent analysis of the dimension-six terms that are generated in the low energy effective theory when a hidden sector that communicates with the Standard Model (SM) through a specific portal operator is integrated out. We work within the Standard Model Effective Field Theory (SMEFT) framework and consider the Higgs, neutrino and hypercharge portals. We find that, for each portal, the forms of the leading dimension-six terms in the low-energy effective theory are fixed and independent of the dynamics in the hidden sector. For the Higgs portal, we find that two independent dimension-six terms are generated, one of which has a sign that, under certain conditions, is fixed by the requirement that the dynamics in the hidden sector be causal and unitary. In the case of the neutrino portal, for a single generation of SM fermions and assuming that the hidden sector does not violate lepton number, a unique dimension-six term is generated, which corresponds to a specific linear combination of operators in the Warsaw basis. For the hypercharge portal, a unique dimension-six term is generated, which again corresponds to a specific linear combination of operators in the Warsaw basis. For both the neutrino and hypercharge portals, under certain conditions, the signs of these terms are fixed by the requirement that the hidden sector be causal and unitary. We perform a global fit of these dimension-six terms to electroweak precision observables, Higgs measurements and diboson production data and determine the current bounds on their coefficients.

We revisit the study of light interacting with QCD axion domain walls from the perspective of the non-linear axion coupling to photons, $g(a) F \tilde F$, which encodes the effects related to the breaking of the axion shift symmetry including the well-known mixing with meson states. As the axion makes an $\mathcal{O}(1)$ excursion of its fundamental period around strings and domain walls, the standard linear coupling to photons is generally insufficient to accurately describe the interaction of light with the defects, and one needs to consider the full structure of $g(a)$. We take this into account in evaluating the friction experienced by axion domain walls moving in a thermal bath of photons, as well as in deriving the birefringent properties of the walls. This clarifies some results in the literature dealing with a special cancellation that takes place for the QCD axion with the electromagnetic and color anomaly as predicted by minimal Grand Unified Theories.

Pseudoscalar and axial neutral and charged pion-constituent quark coupling constants are investigated with nondegenerate quark masses in different kinematical points, off shell and on shell pions and constituent quarks. For the neutral pion, mixing effects are introduced by means of the pion mixing to states $P_0$ and $P_8$, that give rise to the $\pi^0-\eta-\eta'$ meson mixing, and mixing of quark currents via corresponding mixing interactions. The relative behavior of charged and neutral pion coupling constants to quarks may be nearly the same - in the framework of the constituent quark model - as the pion-nucleon coupling constants if mixings are introduced. A very small pion coupling to strange quark current is also obtained. The dependence of the positive and negative pion-constituent quark coupling constant on the non-degeneracy of quark masses, for emission and absorption processes, is identified.

We present a novel mechanism for the irreducible production of magnetic monopoles from interactions of cosmic rays and interstellar medium (ISM). Resulting monopoles drain energy from galactic magnetic fields, disrupting their formation and sustainability. We generalize conventional Parker bounds to monopoles with extended energy spectrum and, considering cosmic ray ISM monopole production, set novel constraints from disruption of Milky Way Galactic magnetic fields and their seeds. Further, we set first constraints on disruption of galactic magnetic fields and their seeds of Andromeda galaxy, with results being competitive with distinct existing bounds. Unlike Parker limits of previous works that relied on cosmological monopoles, our constraints are independent of cosmological monopole production or their primordial abundance. Besides, we estimate new constraints on dipole magnetic moments generated from cosmic ray ISM interactions. We discuss implications for monopoles with generalized magnetic charges.

We discuss ways to discriminate at hadron colliders between a quasi-bound toponium state and a pseudoscalar Higgs boson A, as predicted in many extensions of the Standard Model. We apply the discussion to the excess of t tbar threshold events recently observed at the LHC by the CMS collaboration \cite{CMS}, which could be due to either possibility. Working in an effective theory in which only an additional pseudoscalar A boson is present in the spectrum, with a mass close to the 2 m_t threshold and a significant coupling to top quarks, we discuss the interference between A production in the dominant gluon-fusion process gg \to A with subsequent A\to t tbar decays, and the QCD continuum background, gg\to t tbar. While this interference is absent in the case of toponium, it is essential for evaluating the A interpretation of the CMS excess. It is difficult to resolve the peak/dip structure that it generates because of the experimental smearing of the t tbar invariant mass spectrum. However, by comparing the total A production rates for different integration domains of the t tbar invariant mass or, eventually, at different center of mass energies, one may be able to observe its effects. We then discuss additional mechanisms for A production in pp collisions, including loop-induced production in association with the lighter h boson, gg \to hA, and production in association with top-quark pairs, gg/q\bar q \to t tbar. A These mechanisms have small cross sections at the LHC, and their observation will necessitate higher luminosities or collider energies.

We investigate the QCD phase transition and its phase structure within Einstein-Maxwell-Dilaton-scalar system and compare the results with those obtained from the Einstein-Maxwell-Dilaton system. It is shown that both models reproduce behavior consistent with lattice QCD. In particular, the Einstein-Maxwell-Dilaton-scalar system exhibits a first-order phase transition in the pure gauge sector, aligning with predictions from Yang-Mills theory. Based on these models, we construct a holographic model for neutron stars, incorporating leptons to satisfy electric charge neutrality, and examine the cold equation of state, the mass-radius relation, and tidal deformability of neutron stars. It is demonstrated that the Einstein-Maxwell-Dilaton-scalar system enables us to describe neutron star properties that meet current astrophysical constraints.

We update a previous N$^3$LL$^\prime$+${\cal O}(\alpha_s^3)$ determination of the strong coupling from a global fit to thrust data by including newly available perturbative ingredients, upgrading the renormalization scales to include a fully canonical scaling region, and implementing the log resummation in a way which ensures the integrated cross section is unaffected by the the leading $1/Q$ hadronization power corrections. Detailed discussions are provided concerning the stability of the results under variations of the fit range and the importance of summing up higher-order logarithmic terms for convergence and stability. We show that high-precision results can be achieved even when carrying out a more conservative fit by restricting the dataset to a region which is more clearly dominated by dijet events. This leads to $\alpha_s(m_Z) = 0.1136 \pm 0.0012$ with $\chi^2/{\rm dof}=0.86$, fully compatible with earlier results using a larger fit range. We also demonstrate that a number of additional effects associated to power corrections have a small impact on this fit result, including modifications to the renormalon substraction scheme for dijet power corrections and the inclusion of three-jet power correction models. The fit is also shown to provide very good agreement with data outside the fit range.

We study a simple class of flavored scalar models, in which the couplings of a new light scalar to standard-model fermions are controlled by the flavor symmetry responsible for fermion masses and mixings. The scalar couplings are then aligned with the Yukawa matrices, with small but nonzero flavor-violating entries. $D$-meson decays are an important source of scalar production in these models, in contrast to models assuming minimal flavor violation, in which $B$ and $K$ decays dominate. We show that FASER2 can probe large portions of the parameter space of the models, with comparable numbers of scalars from $B$ and $D$ decays in some regions. If discovered, these particles will not only provide evidence of new physics, but they may also shed new light on the standard model flavor puzzle. Finally, the richness of theoretical models underscores the importance of model-independent interpretations. We therefore analyze the sensitivity of FASER and other experimental searches in terms of physical parameters:~(i) the branching fractions of heavy mesons to the scalar, and (ii) $\tau/m$, where $\tau$ and $m$ are the scalar's lifetime and mass, respectively. The results are largely independent of the new particle's spin and can be used to extract constraints on a wide variety of models.

Recent research has revealed that the CRT symmetry for fermions exhibits a fractionalization distinct from the $\mathbb{Z}_2^{\mathcal{C}}\times\mathbb{Z}_2^{\mathcal{R}}\times\mathbb{Z}_2^{\mathcal{T}}$ for scalar bosons. In fact, the CRT symmetry for fermions can be extended by internal symmetries such as fermion parity, thereby forming a group extension of the $\mathbb{Z}_2$ direct product. Conventionally, a Majorana fermion is defined by one Dirac fermion with trivial charge conjugation. However, when the spacetime dimension $d+1=5,6,7\bmod8$, the real dimension of Majorana fermion (dim$_{\mathbb{R}}\chi_{\mathcal{C}\ell(d,0)}$) aligns with the real dimension of Dirac fermion (dim$_{\mathbb{R}}\psi_{\mathcal{C}\ell(d)}$), rather than being half, which necessitates the introduction of a symplectic Majorana fermion, defined by two Dirac fermions with trivial charge conjugation. To include these two types of Majorana fermions, we embed the theory in $n_{\mathbb{R}}$ and define the Majorana fermion field as a representation of the real Clifford algebra with 8-fold periodicity. Within the Hamiltonian formalism, we identify the 8-fold CRT-internal symmetry groups across general dimensions. Similarly, Dirac fermion field is defined as a representation of the complex Clifford algebra with 2-fold periodicity. Interestingly, we discover that the CRT-internal symmetry groups exhibit an 8-fold periodicity that is distinct from that of the complex Clifford algebra. In certain dimensions where distinct mass terms can span a mass manifold, the CRT-internal symmetries can act non-trivially upon this mass manifold. Employing domain wall reduction method, we are able to elucidate the relationships between symmetries across different dimensions.

Stellar streams from disrupted globular clusters are dynamically cold structures that are sensitive to perturbations from dark matter subhalos, allowing them in principle to trace the dark matter substructure in the Milky Way. We model, within the context of $\Lambda$CDM, the likelihood of dark matter subhalos to produce a significant feature in a GD-1-like stream and analyze the properties of such subhalos. We generate a large number of realizations of the subhalo population within a Milky Way mass host halo, accounting for tidal stripping and dynamical friction, using the semi-analytic code SatGen. The subhalo distributions are combined with a GD-1-like stream model, and the impact of subhalos that pass close to the stream are modeled with Gala. We find that subhalos with masses in the range $5\times 10^6 M_{\odot} - 10^8 M_{\odot}$ at the time of the stream-subhalo encounter, corresponding to masses of about $4 \times 10^7 M_{\odot} - 8 \times 10^8 M_{\odot}$ at the time of infall, are the likeliest to produce gaps in a GD-1-like stream. We find that gaps occur on average $\sim$1.8 times per realization of the host system. These gaps have typical widths of $\sim(7 - 27)$ deg and fractional underdensities of $\sim (10 - 30)\%$, with larger gaps being caused by more-massive subhalos. The stream-subhalo encounters responsible for these have impact parameters $(0.1 - 1.5)$ kpc and relative velocities $\sim(170 - 410)$ km/s. For a larger host-halo mass, the number of subhalos increases, as do their typical velocities, inducing a corresponding increase in the number of significant stream-subhalo encounters.

We apply the method of moments to the relativistic Boltzmann-Vlasov equation and derive the equations of motion for the irreducible moments of arbitrary tensor-rank of the invariant single-particle distribution function. We study two cases, in the first of which the moments are taken to be irreducible with respect to the little group associated with the time-like fluid four-velocity, while in the second case they are assumed to be also irreducible with respect to a space-like four-vector orthogonal to the fluid four-velocity, which breaks the spatial isotropy to a rotational symmetry in the plane transverse to this vector. A systematic truncation and closure of the general moment equations leads, in the first case, to a theory of relativistic higher-order dissipative resistive magnetohydrodynamics. In the second case, we obtain a novel theory of dissipative resistive anisotropic magnetohydrodynamics, where the momentum anisotropy is in principle independent from that introduced by the external magnetic field.

The Boltzmann equation relates the equilibrium phase space distribution of stars in the Milky Way to the Galaxy's gravitational potential. However, observations of stellar populations are biased by extinction from foreground dust, which complicates measurements of the potential in the disk and towards the Galactic center. Using the kinematics of Red Clump and Red Branch stars in Gaia DR3, we use machine learning to simultaneously estimate both the unbiased stellar phase space density and the gravitational potential. The unbiased phase space density is obtained through a learned "dust efficiency factor" -- an observational selection function that accounts for dust extinction. The potential and the dust efficiency are parameterized by fully connected neural networks and are completely data driven. We validate the dust efficiency using a recent three-dimensional dust map in this work, and examine the potential in a companion paper.

In this work, I investigate the impact of Dark Energy Spectroscopic Instrument (DESI) Baryonic Acoustic Oscillations (BAO) data on cosmological parameters, focusing on the inflationary spectral index $n_s$, the amplitude of scalar perturbations $A_s$, and the matter density parameter $\omega_m$. By examining different models of late-time new physics, the inflationary parameters were revealed to be stable when compared with the baseline dataset that used the earlier BAO data from the SDSS collaboration. When combined with Cosmic Microwave Background (CMB) and type Ia supernovae (SNeIa), DESI BAO data leads to a slight reduction in $\omega_m$ (less than 2\%) and modest changes in $A_s$ and $n_s$, if compared with the same combination but using SDSS BAO data instead, suggesting a subtle shift in matter clustering. These effects may be attributed to a higher expansion rate from dynamical dark energy, changes in the recombination period, or modifications to the matter-radiation equality time. Further analyses of models with dynamical dark energy and free curvature show a consistent trend of reduced $\omega_m$, accompanied by slight increases in both $n_s$ and $H_0$. The results emphasize the importance of the DESI BAO data in refining cosmological parameter estimates and highlight the stability of inflationary parameters across different late-time cosmological models.

Top quark pair production in association with a W boson is a rare standard model process that has proven to be an intriguing puzzle for theorists and experimentalists alike. Recent measurements, performed at $\sqrt{s}$ = 13 TeV, by both the ATLAS and CMS Collaborations at the CERN LHC, find cross section values that are consistently higher than the latest state-of-the-art theory predictions. In this presentation, both experimental and theoretical challenges in the pursuit of a better understanding of this process are discussed. Furthermore, a framework for a future differential measurement to be performed with the Run 2 CMS data (collected in 2016-2018) is proposed.

In models of warm dark matter, there is an appreciable population of high momentum particles in the early universe, which free stream out of primordial over/under densities, thereby prohibiting the growth of structure on small length scales. The distance that a dark matter particle travels without obstruction, known as the free streaming length, depends on the particle's mass and momentum, but also on the cosmological expansion rate. In this way, measurements of the linear matter power spectrum serve to probe warm dark matter as well as the cosmological expansion history. In this work, we focus on ultra-light wave wave dark matter (WWDM) characterized by a typical comoving momentum $q_\ast$ and mass $m$. We first derive constraints on the WWDM parameter space $(q_\ast, m)$ using Lyman-$\alpha$ forest observations due to a combination of the free-streaming effect and the white-noise effect. We next assess how the free streaming of WWDM is affected by three modified expansion histories: early matter domination, early dark energy, and very early dark energy.

Dark matter halos with self-interacting dark matter (SIDM) experience a unique evolutionary phenomenon, in that their central regions eventually collapse to high density through the runaway gravothermal process after initially forming a large and low-density core. When coupled with orbital evolution, this is expected to naturally produce a large diversity in dark-matter halos' inner mass distribution, potentially explaining the diversity problem of dwarf galaxies. However, it remains unknown how the diversity in SIDM dark-matter halos propagates to the more easily observed luminous matter at the center of the halo, especially the stellar component. In this work, we use idealized N-body simulations with two species of particles (dark matter and stars) to study the response of the stellar properties of field and satellite dwarf galaxies to SIDM evolution and orbital effects on their halos. Galaxies' stellar components, including galaxy size, mass-to-light ratio, and stellar velocity dispersion, display a much larger scatter in SIDM than the standard cold dark matter (CDM) model. Importantly, we find signs of universality in the evolution pathways, or ``tidal tracks'', of SIDM dwarf satellites, which are physically interpretable and potentially parameterizable. This type of tidal-track model can be layered onto larger-scale, cosmological simulations to reconstruct the evolution of populations of SIDM dwarfs in cases where high-resolution simulations of galaxies are otherwise prohibitively expensive.

We search for an excess of electrons and positrons in the interplanetary space from the decays of heavy neutrinos produced in nuclear reactions in the Sun. Using measurements of the electron spectra in the MeV range from the Ulysses and SOHO satellites, we report the strongest direct upper bound to date on the mixing between heavy neutral leptons with MeV masses and electron neutrinos, reaching $U_e^2\simeq 10^{-6}$ at $M_N=10$ MeV. Our sensitivity is predominantly constrained by the uncertainties in the propagation of electrons and positrons, particularly the diffusion coefficient in the inner Solar System, as well as the uncertainties in the astrophysical background. Enhancing our understanding of either of these factors could lead to a significant improvement in sensitivity.

Differential top quark pair cross sections are measured in the dilepton final state as a function of kinematic variables associated to the dineutrino system. The measurements are performed making use of the Run 2 dataset collected by the CMS experiment at the CERN LHC collider, corresponding to proton-proton collisions recorded at center of mass energy of 13 TeV and an integrated luminosity of 138 fb$^{-1}$. The measured cross sections are found in agreement with theory predictions and Monte Carlo simulations of standard model processes.

The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino oscillation experiment aimed at determining the neutrino mass hierarchy and the CP-violating phase. The DUNE physics program also includes the detection of astrophysical neutrinos and the search for signatures beyond the Standard Model, such as nucleon decays. DUNE consists of a near detector complex located at Fermilab and four 17 kton Liquid Argon Time Projection Chamber (LArTPC) far detector modules to be built 1.5 km underground at SURF, approximately 1300 km away. The detectors are exposed to a wideband neutrino beam generated by a 1.2 MW proton beam with a planned upgrade to > 2 MW. Two 770 ton LArTPCs (ProtoDUNEs) have been operated at CERN for over 2 years as a testbed for DUNE far detectors and have been optimized to take new cosmic and test-beam data in 2024-2025. The DUNE and ProtoDUNE experiments and physics goals, as well as recent progress and results, are presented.

This summary of the second Terrestrial Very-Long-Baseline Atom Interferometry (TVLBAI) Workshop provides a comprehensive overview of our meeting held in London in April 2024, building on the initial discussions during the inaugural workshop held at CERN in March 2023. Like the summary of the first workshop, this document records a critical milestone for the international atom interferometry community. It documents our concerted efforts to evaluate progress, address emerging challenges, and refine strategic directions for future large-scale atom interferometry projects. Our commitment to collaboration is manifested by the integration of diverse expertise and the coordination of international resources, all aimed at advancing the frontiers of atom interferometry physics and technology, as set out in a Memorandum of Understanding signed by over 50 institutions.

We present the first theoretical study of the polarization of lepton pairs produced in $\sqrts = 5.02 $ TeV Pb+Pb collisions at the LHC, using next-to-leading order (NLO) dilepton emission rates. These calculations employ a multi-stage framework to simulate the evolution of relativistic heavy-ion collisions, and to explore the sensitivity of polarization to early times. It is found that the intermediate invariant-mass dileptons are indeed probes of the thermal equilibration process, and go beyond the reach of hadronic observables. We compute the polarization anisotropy coefficient obtained with LO dilepton rates, and show that the LO and NLO results differ radically, both in trend and in magnitude, at low and intermediate lepton pair invariant masses.

The standard cosmological model currently in force, aka $\Lambda$CDM, has been plagued with a variety of tensions in the last decade or so, which puts it against the wall. At the core of the $\Lambda$CDM we have a rigid cosmological term, $\Lambda$, for the entire cosmic history. Recently, the results from the DESI collaboration suggested the possibility that dark energy (DE) should be dynamical rather than just a cosmological constant. Using a generic $w_0w_a$CDM parameterization, DESI favors quintessence behavior at $\sim 3\sigma$ c.l. However, to alleviate the tensions the DE needs more features. In the proposed $w$XCDM model of [43] the DE is actually a composite cosmic fluid with two components $(X,Y)$ acting sequentially: first $X$ (above a transition redshift $z_t$) and second $Y$ (below $z_t$). Fitting the model to the data, we find that the late component $Y$ behaves as quintessence, like DESI. However, to cure the $H_0$ and growth tensions, $X$ must behave as `phantom matter' (PM), which in contrast to phantom DE provides positive pressure at the expense of negative energy density. Using the SNIa (considering separately Pantheon$+$ and DESY5), cosmic chronometers, transversal BAO, LSS data, and the full CMB likelihood from Planck 2018, we find that both tensions can be completely cut down. We also compare the $w$XCDM with our own results using the standard $w$CDM and $w_0w_a$CDM parameterizations of the DE. In all cases, model $w$XCDM performs much better. Finally, we have repeated our analysis with BAO 3D data (replacing BAO 2D), and we still find that the dynamical DE models (including composite ones) provide a much better fit quality compared to $\Lambda$CDM. The growth tension is alleviated again, but in contrast, the $H_0$-tension remains significant, which is most likely reminiscent of the internal conflict in the BAO sector.

We present a new, cosmologically model-independent, statistical analysis of the Pantheon+ type Ia supernovae spectroscopic dataset, improving a standard methodology adopted by Lane et al. We use the Tripp equation for supernova standardisation alone, thereby avoiding any potential correlation in the stretch and colour distributions. We compare the standard homogeneous cosmological model, i.e., $\Lambda$CDM, and the timescape cosmology which invokes backreaction of inhomogeneities. Timescape, while statistically homogeneous and isotropic, departs from average Friedmann-Lema\^{\i}tre-Robertson-Walker evolution, and replaces dark energy by kinetic gravitational energy and its gradients, in explaining independent cosmological observations. When considering the entire Pantheon+ sample, we find very strong evidence ($\ln B> 5$) in favour of timescape over $\Lambda$CDM. Furthermore, even restricting the sample to redshifts beyond any conventional scale of statistical homogeneity, $z > 0.075$, timescape is preferred over $\Lambda$CDM with $\ln B> 1$. These results provide evidence for a need to revisit the foundations of theoretical and observational cosmology.

Primordial gravitational waves propagate almost unimpeded from the moment they are generated to the present epoch. Nevertheless, they are subject to convolution with a non-trivial transfer function. Within the standard thermal history, shifts in the temperature-redshift relation combine with damping effects by free streaming neutrinos to non-trivially process different wavelengths during radiation domination, with subsequently negligible effects at later times. Presuming a nearly scale invariant primordial spectrum, one obtains a characteristic late time spectrum, deviations from which would indicate departures from the standard thermal history. Given the paucity of probes of the early universe physics before nucleosynthesis, it is useful to classify how deviations from the standard thermal history of the early universe can be constrained from observations of the late time stochastic background. The late time spectral density has a plateau at high frequencies that can in principle be significantly enhanced or suppressed relative to the standard thermal history depending on the equation of state of the epoch intervening reheating and the terminal phase of radiation domination, imprinting additional features from bursts of entropy production, and additional damping at intermediate scales via anisotropic stress production. In this paper, we survey phenomenologically motivated scenarios of early matter domination, kination, and late time decaying particles as representative non-standard thermal histories, elaborate on their late time stochastic background, and discuss constraints on different model scenarios.

This paper calculates the stochastic gravitational wave background from dark binaries with finite-range attractive dark forces, complementing previous works which consider long-range dark forces. The finiteness of the dark force range can dramatically modify both the initial distributions and evolution histories of the binaries. The generated gravitational wave spectrum is enhanced in the intermediate frequency regime and exhibits interesting "knee" and "ankle" features, the most common of which is related to the turn on of the dark force mediator radiation. Other such spectral features are related to changes in the binary merger lifetime and the probability distribution for the initial binary separation. The stochastic gravitational wave background from sub-solar-mass dark binaries is detectable by both space- and ground-based gravitational wave observatories.

Understanding the Page curve and resolving the black hole information puzzle in terms of the entanglement dynamics of black holes has been a key question in fundamental physics. In principle, the current quantum computing can provide insights into the entanglement dynamics of black holes within some simplified models. In this regard, we utilize quantum computers to investigate the entropy of Hawking radiation using the qubit transport model, a toy qubit model of black hole evaporation. Specifically, we implement the quantum simulation of the scrambling dynamics in black holes using an efficient random unitary circuit. Furthermore, we employ the swap-based many-body interference protocol for the first time and the randomized measurement protocol to measure the entanglement entropy of Hawking radiation qubits in IBM's superconducting quantum computers. Our findings indicate that while both entanglement entropy measurement protocols accurately estimate the R\'enyi entropy in numerical simulation, the randomized measurement protocol has a particular advantage over the swap-based many-body interference protocol in IBM's superconducting quantum computers. Finally, by incorporating quantum error mitigation techniques, we establish that the current quantum computers are robust tools for measuring the entanglement entropy of complex quantum systems and can probe black hole dynamics within simplified toy qubit models.