We present a detailed analysis of the spectral data of Borexino Phase II, with
the aim of exploiting its full potential to constrain scenarios beyond the Standard Model. In
particular, we quantify the constraints imposed on neutrino magnetic moments, neutrino
non-standard interactions, and several simplified models with light scalar, pseudoscalar
or vector mediators. Our analysis shows...
Starobinsky inflation is an attractive, fundamental model to
explain the Planck measurements, and its higher-order extension may
allow us to probe quantum gravity effects. We show that future CMB
data combined with the 21cm intensity map from SKA will meaningfully
probe such an extended Starobinsky model. A combined analysis will
provide a precise measurement and intriguing...
The MicroBooNE detector is a Liquid Argon Time Projection Chamber (LArTPC) located along the Booster Neutrino Beam at Fermilab. One of MicroBooNE’s key physics goals is the measurement of neutrino-argon cross sections. The MicroBooNE detector’s fully active volume and precision reconstruction and calorimetry allow for accurate measurements of lepton kinematics as well as visible hadronic...
We investigate the Teukolsky equations in horizon-penetrating coordinates to study the behavior of perturbation waves crossing the outer horizon. For this purpose, we use the null ingoing/outgoing Eddington-Finkelstein coordinates. We find that the radial equation is a confluent form of Heun’s differential equation in both ingoing/outgoing coordinates, with three singularities. The radial...
In this talk we will discuss the possibility that a gauged U(1)' symmetry mediates dark matter self interactions. The breaking of this symmetry induces a Z-Z' mass mixing term, connecting the dark and visible sectors. After symmetry breaking of the U(1)', the fermion content of the dark sector is divided into right handed neutrinos and a stable dark matter candidate. We discuss the neutrino...
The discovery of the Higgs boson with the mass of 125 GeV confirmed the mass generation mechanism via spontaneous electroweak symmetry breaking and completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many experimental measurements, it is not capable of solely explaining some observations. Many extensions of the Standard...
I put forward a novel variation method for calculating the mass and PDF of hadrons in 1+1D models. The template functions in our method minimize a Free Energy functional composed of free partons kinetic energy and Renyi entropy of all pairs of partons. Our results suggest hadrons in these models minimize this Free Energy functional. I will comment on extending our calculation to confining...
Secondary charged particles in proton beam dump experiments offer a new production mechanism for new particles like dark photons. Proton beam dump experiments produce a multitude of secondary charged pions. As the charged pions travel down the beam path, they scatter off of the target’s nuclei and can radiate a dark photon. We use chiral perturbation theory to calculate the production of dark...
MicroBooNE is a neutrino experiment that utilizes a single-phase liquid argon time projection chamber (LArTPC) located on-axis in the Booster Neutrino Beam at Fermilab. One of its primary goals is to investigate the nature of the excess of low-energy electromagnetic-like events observed by the MiniBooNE collaboration. In this talk, I will present the recent results from MicroBooNE’s low energy...
In this talk, we will present a study on the effects of the dark Z model in current and future low-energy parity-violating experiments. In particular, we will give the constraints from electroweak pole observables, CEvNS, BaBar, and the future sensitivity for SoLID. We will also present a re-analysis of other existing or upcoming low-energy experiments, such as E158, Qweak, P2, MOLLER, and...
Primordial black holes (PBHs) within the mass range $10^{17} - 10^{22}$ g are a favorable candidate for describing all of the dark matter content. Towards the lower end of this mass range, the Hawking temperature, $T_H$, of these PBHs is $T_H > 100$ keV, allowing for the creation of electron-positron pairs, thus making their Hawking radiation a useful constraint for most current and future...
We explore the neutrino sector of the minimal left-right symmetric model, with the additional charge conjugation discrete symmetry, in the novel regime where type-I and type-II seesaw mechanisms are equally responsible for the light neutrino masses, which can result in large active-sterile mixing. We show that unless the charged lepton mixing matrix is the identity and the right handed...
Vectorlike leptons are an intriguing possibility for physics beyond the Standard Model. This talk is concerned with the example of weak isosinglet vectorlike leptons that decay through a small mixing with the tau lepton, for which the discovery and exclusion reach of the Large Hadron Collider and future proposed hadron colliders is limited. For this minimal model, I will argue that an $e^+...
In the non-relativistic limit, scattering of two particles by boson exchange can be described using a static potential, i.e, that of a force between them. The exchange of two fermions can also lead to a force, as if the two fermions behave like an effective boson. These forces are called "quantum forces", and the range of these forces is inversely proportional to the mass of the fermions being...
The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association...
In canonical quantum mechanics (QM), energy eigenstates can be thought of as evolving in the phase space of a classical harmonic oscillator. Nambu quantum mechanics is a particular generalization of canonical QM whereby this phase space is extended to that of an asymmetric top, introducing two “deformation parameters”. Canonical QM can then be interpreted as the limiting case where both of...
Precision measurements of the production cross-sections of W/Z boson at LHC provide important tests of perturbative QCD, information about the parton distribution functions for quarks within the proton and fundamental parameters of the Standard Model. Extremely precise double-differential measurement of Z transverse momentum and rapidity at centre-of-mass energy of 8 TeV will be presented....
Many theories beyond the Standard Model (SM) predict that New Physics (NP) will manifest by decaying into final states involving leptons. Leptoquarks are predicted by different NP theories to describe similarities between the lepton and quark sectors of the SM. Other NP theories relating to quantum gravity predict periodic signatures in dilepton final states, where tightly-spaced resonance...
We present a method to verify Mikheyev-Smirnov-Wolfenstein effect during the propagation of SN neutrinos from the SN core to the Earth. The non-MSW scenarios to be distinguished from the MSW one are the incoherent flavor transition probability for neutrino propagation in the vacuum and the flavor equalization induced by fast flavor conversions. Our approach involves studying time evolution of...
The origin of Majorana neutrino masses in a Majoron model provide a well-motivated scenario for the generation of identifiable primordial stochastic background of gravitational waves. In this talk I will discuss how a spectrum with a joint contribution both from a strong first order phase transition and from global cosmic strings can emerge naturally in these models. Moreover, the interplay...
Measurements of heavy quark hadronization fractions, or the probabilities $f_q$ that a bottom quark forms one of the weakly decaying B hadrons, are essential for precision measurements of B branching fractions made at hadron colliders and potentially limit searches for new physics in $B_s$ decays. Although once thought to be universal, recent measurements have suggested an environmental and...
Lepton Flavor Violation (LFV) is one of the cleanest probes of Beyond the Standard Model (BSM) Physics. In this work, we explore the sensitivity of the channel $e^+ e^- \to \tau \mu$ to BSM physics above the $\sim$ TeV scale at the proposed circular electron-positron collider FCC-ee. We compute the expected cross-section $\sigma(e^+ e^- \to \tau \mu)$ in the Standard Model Effective Field...
The Randall-Sundrum model has been a great source of interest to theorists
and phenomenologists for over two decades, both for its novel solution to the hierarchy problem, and its phenomenological consequences. The modulus field associated with the warped extra dimension of this model requires stabilization. In this talk I will present ongoing work to investigate the feasibility of...
Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. This talk will present the latest results from SUSY searches conducted by the ATLAS experiment. The searches target multiple final states and different assumptions about the decay mode of the produced SUSY particles,...
The isotropic signal of neutrinos from all past core-collapse supernovae, known as the diffuse supernova neutrino background (DSNB), is close to being detected in Super-Kamiokande. The most optimistic models are already disfavored with current upper limits so improving our theoretical understanding of the DSNB is crucial in the next few years, especially with upcoming detectors. We discuss the...
Black hole superradiance is a phenomenon in which, purely through gravitational interactions, light bosons are spontaneously produced outside spinning black holes. Through this effect, an exponentially growing Bose-Einstien condensate cloud forms around the black hole. In the case of dark photon superradiance, the cloud can form into strings of magnetic flux analogous to Abrikosov vortices in...
Long-baseline (LBL) accelerator neutrino oscillation experiments, such as NOvA and T2K in the current generation, and DUNE-LBL and HK-LBL in the coming years, will measure the remaining unknown oscillation parameters with excellent precision. These analyses assume external input on the solar parameters, $\theta_{12}$ and $\Delta m^2_{21}$, from solar experiments such as SNO, SK, and Borexino,...
The high center-of-mass energy of proton-proton collisions and the large available datasets at the CERN Large Hadron Collider allow to study rare processes of the Standard Model (SM) with unprecedented precision and search for new physics that might enhance extremely rare processes in the SM. Measurements of rare SM processes provide new tests of the SM predictions with the potential to unveil...
I will describe the collider phenomenology of near-continuum dark matter, a model that gives rise to a gapped tower of Kaluza-Klein (KK) states. The model is coupled to the Standard Model via a Z-portal coupling, and the unique experimental signatures of this model include a cascade decay with large displaced vertices, a characteristic fermion energy spectrum, and more, all of which will be...
We present predictions of the cross section of ultrahigh-energy neutrino-nucleon scattering. The calculations are based on CT18NNLO parton distribution functions and their uncertainties. For the highest energies, we extrapolate the PDFs to small x according to several assumptions, which affect the uncertainties at such high energies. The results can be applied to astrophysical neutrino...
In this talk I will propose to probe the Higgs boson decay to invisible particles at a muon collider by observing the forward muons that are produced in association with the Higgs in the Z-boson fusion channel. I will argue that an excellent sensitivity is possible provided a forward muon detector is installed. We find that the resolution on the measurement of the muon energy and angle will be...
We describe a new jet clustering algorithm named SIFT (Scale-Invariant Filtered Tree) that maintains the resolution of substructure for collimated decay products at large boosts. The scale-invariant measure combines properties of kT and anti-kT by preferring early association of soft radiation with a resilient hard axis, while avoiding the specification of a fixed cone size. Integrated...
We consider the gauged $B-L$ model which is extended with a secluded dark sector, comprising of two dark sector particles. In this framework the lightest $Z_2$-odd particle is the dark matter candidate, having a feeble interaction with all other SM and BSM states. The next-to-lightest $Z_2$-odd particle in the dark sector is a super-wimp, with large interaction strength with the SM and BSM...
We analyze the UV breakdown of sub-GeV Dark Matter Models that live in a new, dark U(1) sector. Many of these models include a scalar field, which is either the Dark Matter itself or a dark Higgs field that generates mass terms for the Dark Matter particle via Spontaneous Symmetry Breaking. A quartic self coupling of this scalar field is generically allowed, and we show that its running is...
I will discuss theories of a complete mirror world with parity (P) solving the strong CP problem. P exchanges the entire Standard Model with its mirror copy and two new mass scales arise: v' where parity and mirror electroweak symmetry are spontaneously broken, and v3 where the color groups break to the diagonal strong interactions. The strong CP problem is solved even if v3 << v' and the...
A muon collider provides an interesting opportunity to test various aspects of Higgs physics and potential BSM models. For a muon collider, Vector-boson fusion provides the dominant channel for the production of Higgs bosons. We calculate the lowest and higher order Higgs jet distribution as a function of jet invariant mass for the super-renormalizable splitting $h\rightarrow hh$ and compare...
We present a new calculation of dark matter-electron scattering rates in semiconductors using atomic centered gaussian basis sets within the framework of density functional theory. We treat both core and valence orbitals similarly and compare with prior results, emphasizing the importance of all-electron effects, which enhance dark-matter electron scattering rates at high recoil energies. We...
I introduce a new method for calculating the dark matter (DM) scattering rate in a directionally sensitive detector, which for the most complicated analyses can be multiple orders of magnitude faster than previous approaches. The new method projects each ingredient of the rate calculation, such as the DM velocity distribution, onto a basis of orthogonal functions. This reduces the rate...
Twin Higgs models address the hierarchy problem and can provide interesting dark matter possibilities. However, the cosmology of these models can be problematic.
I present a new twin Higgs model in which the usual color group originates from the spontaneous breaking of a gauged SU(4) symmetry in the visible sector. In the hidden sector the SU(4) is not broken leading to new dark matter...
We propose a scenario where dark matter (DM) with a wide mass range from a few keV to PeV can be produced solely from evaporating primordial black holes (PBH), while being consistent with the required free streaming length for structure formation. If DM does not have any other interactions apart from gravity and the universe has a PBH dominated phase at early epoch, then PBH evaporation...
In this talk, I discuss the production of a spectator scalar dark matter field that directly couples to the inflaton. Two specific inflationary potentials, the Starobinsky and T-model of inflation, are considered, which satisfy the constraints on the scalar tilt (n_s) and tensor-to-scalar ratio (r) as measured by the Planck satellite. Excitation of the light scalar dark matter during inflation...
Direct detection for sub-GeV dark matter is developing rapidly, with many novel experimental ideas and theoretical methods emerging. In this work, we extend the dielectric formalism for dark matter scattering to incorporate anisotropic material responses, enabling directionally-sensitive experiments with a broad class of target materials. Using a simple model of an anisotropic electron gas, we...
The hadronization process plays a crucial role in Monte Carlo event generators, where quarks and gluons are combined into observable hadrons. However, while current phenomenological models have been quite successful overall in simulating this process, there remain phenomenological areas where they still lack accuracy in describing the underlying physics. Recent research has taken a new...
Using a simple eikonal approach to the treatment of Coulomb-nuclear interference and form-factors effects and taking into account the curvature effects in high-energy $pp$ and $\bar{p}p$ scattering, we determine the basic parameters $B$, $\rho$, and $\sigma_{\rm tot}$ from fits to experiment at $W=\sqrt s=$ 53 GeV, 62.3 GeV, 8 TeV, and 13 TeV. We then investigate the differential cross...
Anomaly Mediated Supersymmetry Breaking or AMSB is a promising new technique that allows one to use the solvability of SUSY chiral theories and translate that in a standard way into non-SUSY theories. I will discuss how this new method works and apply it to a certain set of chiral gauge theories with fields in the fundamental, antifundamental and antisymmetric representations. I find that this...
We consider the possibility of constraining the dark matter distribution in the Shapley Supercluster from the velocity distribution of galaxy clusters and galaxies with in it.
We present a gauged baryon number model as an example of models where all new fermions required to cancel out the anomalies help to solve phenomenological problems of the standard model (SM). Dark fermion doublets, along with the isosinglet charged fermions, in conjunction with a set of SM-singlet fermions, participate in the generation of small neutrino masses through the Dirac-dark Zee...
The electron-ion collider (EIC), a new powerful high-luminosity
facility, will be able to open up new windows of opportunities to explore new physics. In this
paper, we study the potential of the EIC to probe the coupling between axion-like particles
(ALPs) and photons in coherent scattering, where the ion stays intact, resulting in a cross section
enhancement proportional to the square of...
The Migdal effect, ionization induced by a nuclear recoil, is an important atomic process for pushing conventional dark matter searches into the MeV mass range. The Migdal effect has of yet not been definitively observed using standard model probes. We have studied the viability of measuring the neutron induced Migdal effect in liquid xenon, silicon, and liquid argon. We present the results of...
We revisit the combinatorial problem at the LHC, taking $t\bar{t}$ production as an example. The combinatorial ambiguity in this case can be reformulated in terms of a quadratic unconstrained binary optimization problem. Finding the solution to the combinatorial problem becomes equivalent to finding the ground state of the Ising Hamiltonian. We explore several variational quantum algorithms to...
We present a first calculation of the unpolarized proton's isovector transverse-momentum-dependent parton distribution functions (TMDPDFs) from lattice QCD, which are essential to predict observables of multi-scale, semi-inclusive processes in the standard model. We use a $N_f=2+1+1$ MILC ensemble with valence clover fermions on a highly improved staggered quark sea (HISQ) to compute the quark...
We present a decision tree-based implementation of autoencoder anomaly detection. A novel algorithm is presented in which a forest of decision trees is trained only on background and used as an anomaly detector. The fwX platform is used to deploy the trained autoencoder on FPGAs within the latency and resource constraints demanded by level 1 trigger systems. Results are presented with two...
We present a calculation of the master integrals (MI's) required for the calculation of the Electroweak corrections to $gg\rightarrow \gamma\gamma$ production in which the process contains a light quark loop.
The integrals can be broken down into four categories based on the flow of the heavy vector bosons throughout the loop. Two of the families are planar, and two are non-planar. We...
Atomic dark matter (ADM) is a simple extension to the Standard Model that is motivated by considerations in both particle and astrophysics. ADM can alter structure formation on subgalactic scales due to its ability to dissipate energy through cooling mechanisms, but is also one realisation of a possible complex dark sector. These dark sectors have been previously studied as a solution to the...
SENSEI (Sub-Electron Noise Skipper Experimental Instrument) is a direct detection dark matter experiment with detectors operating at Fermilab and at the SNOLAB underground facility. The experiment consists of silicon Skipper-CCD sensors that make multiple non-destructive measurements of the charge contained in each of millions of pixels, reducing the readout noise to a level that allows for...
Although a direct search for the QCD axion at colliders may not be viable due to the feebleness of the axion couplings to the standard model, collider experiments may be sensitive to signatures of the axino, the supersymmetric partner of the axion. The couplings of the axion and axino are related to the axion decay constant $f_{a}$, and so collider searches for the axino may be a way to set...
We find the correct spinor amplitude for a simple photon-mediated process and show that, in contrast, the result for the same process using the standard constructive techniques do not agree with Feynman diagrams when the fermions are massive.
Theory predictions for the LHC require precise numerical phase-space integration and generation of unweighted events. We combine machine-learned multi-channel weights with a normalizing flow for importance sampling, to improve classical methods for numerical integration. We develop an efficient bi-directional setup based on an invertible network, combining online and buffered training for...
Dark matter could be dark baryons made from underlying vector-like quarks which interact with the standard model as an electroweak multiplet. If the lightest dark baryon is electrically neutral with vanishing hypercharge, the leading interaction with the SM is anticipated to be through its magnetic dipole (for fermionic dark baryons). Using the non-relativistic quark model, which becomes exact...
Pulsar timing arrays (PTAs) are a powerful tool to study dark matter (DM) substructure. Transiting lumps of DM can induce shift in pulsar timings due to Doppler and Shapiro effects. In this talk we first briefly review the principle of DM detection with PTAs. We then show the projected reach using the projected subhalo mass function and density profile of DM substructure from various models....
I introduce and study the first class of signals that can probe the dark matter in Mesogenesis which will be observable at current and upcoming large volume neutrino experiments. The well-motivated Mesogenesis scenario for generating the observed matter-anti-matter asymmetry necessarily has dark matter charged under baryon number. Interactions of these particles with nuclei can induce nucleon...
Choosing which properties of the data to use as input to multivariate decision algorithms -- a.k.a. feature selection -- is an important step in solving any problem with machine learning. While there is a clear trend towards training sophisticated deep networks on large numbers of relatively unprocessed inputs (so-called automated feature engineering), for many tasks in physics, sets of...
Whizard is a universal program for computing observables and simulated event samples in multi-parton high-energy collider processes. While it has been developed as a tool for e+e- physics studies, it also covers LHC physics and new collider concepts such as a muon collider. Physics models are supported intrinsically and via the UFO format. Whizard version 3 accounts for the full Standard...
Cosmological parity violation offers a unique way to probe the primordial non-Gaussianity. Recent studies have indicated that measuring parity-violating signals from large-scale structure observations are possible. These signals can arise naturally through the exchange of heavy spinning particles, with chemical potential enhancement, during cosmic inflation. In this talk, we will present a...
Several BSM predicted particles could give rise to resonant particle pair production. We will present the results of a search for prompt low-mass dimuon resonances based on proton-proton collision data at a center-of-mass energy of 13 TeV collected by CMS. The search exploits a high-rate trigger ("scouting") stream to record events with two muons and looks for narrow peaks in the dimuon mass...
We consider the general class of theories in which there is a new ultralight scalar field that mediates an equivalence principle violating, long-range force. In such a framework, the Sun and Earth act as sources of the scalar field, leading to potentially observable location-dependent effects on atomic and nuclear spectra. We determine the sensitivity of current and next-generation atomic and...
Models of particle physics that you care about have generalized symmetries, and understanding them can lead to new insights into these theories. I'll give a brief overview of the sorts of questions one might try to address with this technology.
We propose an asymptotically safe extension of the standard model with gauged baryon number that is spontaneously broken at the TeV scale. Among the new heavy fermions is a potential dark matter candidate which is rendered stable by an unbroken $Z_2$ subgroup of the baryon number gauge group. After taking into account gravitational effects above the Planck scale, we study the ultraviolet fixed...
Dark matter may exist as an ultralight bosonic particle, leading to the formation of an ever-present field that could interact with us via a new long-range fifth force. Recently, quantum sensing techniques have been shown to be promising avenues with which to detect such a dark matter candidate. However, these studies did not entirely capture the stochastic nature of the field, which is...
The QCD axion is a well-motivated extension of the Standard Model which dynamically relaxes away strong CP violation. However, to date most searches for the axion have instead focused on its model-dependent coupling to photons. I will present a new idea for axion detection that directly targets its defining coupling to gluons, by resonantly amplifying the oscillating currents from time-varying...
A weakly coupled and light dark photon coupling to lepton charges $L_\mu-L_\tau$ is an intriguing dark matter candidate that could modify the dynamics of neutrino flavor conversions. By analyzing data from the T2K, SNO, and Super-Kamiokande experiments, limits are obtained on the dark photon gauge coupling for masses below $\sim 10^{-11}\,\mathrm{eV}$. Degeneracies between shifts in the...
Measurements of multiboson production at the LHC probe the electroweak gauge structure of the Standard Model for contributions for anomalous gauge couplings. Processes involving quartic gauge couplings have become experimentally accessible at the LHC. We present recent ATLAS results of vector-boson scattering in the Zgamma channel, where the Z boson decays to neutrinos producing missing...
We study the impact of LHC forward-backward asymmetry (AFB) measurements at high invariant mass in the Drell-Yan process on probes of semi-leptonic four-fermion operators in the Standard Model effective field theory (SMEFT). In particular, we study whether AFB measurements can resolve degeneracies in the Wilson coefficient parameter space that appear when considering invariant mass and...
Although searches for GeV-scale WIMPs are sensitive to very small cross sections, constraints on sub-GeV dark matter are significantly weaker, and largely constrain moderately- or strongly-interacting dark matter. But if dark matter interacts too strongly with nuclei, it could be slowed to undetectable speeds in Earth’s crust or atmosphere before reaching a detector. For sub-GeV dark matter,...
We construct an effective field theory for non-relativistic heavy dark matter of arbitrary spin based on the Little group formalism. We present the most general HDMEFT basis up to dimension seven involving scalar (spin 0), vector (integer spin) and fermionic (half-integer spin) dark matter fields. We also discuss the matching onto the non-relativistic EFT.
Ultralight bosonic particles, including axionlike particles and kinetically mixed dark photons, can be promising dark matter candidates. It was recently shown that the Earth can act as a transducer for ultralight dark matter detection, by converting the dark matter into an oscillating monochromatic magnetic field signal across the Earth's surface. This occurs because the ground and...
Measuring the density profile of dark matter in the Solar neighbourhood has important implications for both dark matter theory and experiment. In this work, we apply autoregressive flows to stars from a realistic simulation of a Milky Way-type galaxy to learn – in an unsupervised way – the stellar phase space density and its derivatives. With these as inputs, and under the assumption of...
The study of high-$p_T$ tails at the LHC can be a complementary probe to low-energy observables when investigating the flavour structure of the Standard Model and its extensions. The Mathematica package HighPT allows to compute Drell-Yan cross-sections for dilepton and monolepton final states at the LHC. The observables can be computed at tree-level in the SMEFT, including the relevant...
The paradigm of portal matter represents a well-motivated extension to models with kinetic mixing/vector portal dark matter. We present a minimal toy model construction using leptonic portal matter that addresses the muon $g-2$ anomaly through chiral enhancement. We further explore a realization of this construction with an extended dark gauge sector in which SM and portal matter fields exist...
The event rates and kinematics of Higgs boson production and decay processes at the LHC are sensitive probes of possible new phenomena beyond the Standard Model (BSM). This talk presents precise measurements of Higgs boson production and decay rates, obtained using the full Run 2 and partial Run 3 pp collision dataset collected by the ATLAS experiment at 13 TeV and 13.6 TeV. These include...
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable...
A new fundamental theory [1] unavoidably predicts supersymmetry, SO(N) grand unification, and a new description of all fundamental scalar bosons. As discussed in our previous papers [2-5] and many recent talks, this last feature in turn unavoidably predicts a dark matter WIMP which is consistent with all experimental and observational constraints, and which should be observable via direct...
We present bounds on 5D theories that have a mass gap followed by a continuous spectrum. These theories involve a metric with a warp factor and are controlled by a single parameter ρ. Using Drell-Yan data simulated from MadGraph, Pythia8, and Delphes for charged lepton and dilepton events we perform a χ2 analysis for the differential cross section predicted by the 5D theory and measured by the...
We discuss the latest status of searches for nonresonant di-Higgs production with the CMS detector. In addition to the analysis strategy and limits on the production cross section of this process, constraints on the Higgs boson self-coupling and the coupling between two Higgs bosons and two vector bosons will be presented.
The black hole images released by the Event Horizon Telescope have opened up a multitude of opportunities to improve our understanding of gravity in strongly curved spacetimes, as well as elucidate the dynamics of turbulent plasma. In this talk, I will connect these two phenomena by demonstrating that the intrinsic variability of reconnection-driven flares in the accretion flow can introduce...
Recent studies reveal that more than a dozen of white dwarfs displaying near-perfect blackbody spectra in the optical range have been lurking in the Sloan Digital Sky Survey catalog. We point out that, in a way analogous to the Cosmic Microwave Background, these stars serve as excellent testbeds for new physics. Specifically, we show how their observed lack of spectral distortions translate...
We demonstrate the ability of future dark matter experiments to probe beyond the standard model (BSM) effects in neutrino scattering of solar and atmospheric origin in models with heavy scalar and vector mediated interactions. Mapping the effective four-Fermi vertex of a scalar NSI to the well studied model of leptoquarks, we find that near future detectors can probe parameter space beyond the...
Observation of lepton number (L) violation by two units at colliders would provide evidence for the Majorana nature of neutrinos. We study signals of L-violation in the context of two popular models of neutrino masses, the type-II seesaw model and the Zee model, wherein small neutrino masses arise at the tree-level and one-loop level, respectively. We focus on L-violation...
In this talk, we discuss a baryonic feedback mechanism induced by dark matter ignition of white dwarf populations, and its potential effects on galaxy evolution and star formation. Previous works have shown that Type Ia supernova ignitions of sub-Chandrasekhar white dwarfs may be caused by asymmetric dark matter captured within white dwarfs, leading to the formation and subsequent collapse of...
The future high-energy muon colliders, featuring both high energy and low background, could play a critical role in our searches for new physics. The smallness of neutrino mass is a puzzle of particle physics. Broad classes of solutions to the neutrino puzzles can be best tested by seeking the partners of SM light neutrinos, dubbed as heavy neutral leptons (HNLs), at muon colliders.
We can...
We present a minimal UV-complete model for sub-GeV thermal Dark Matter (DM) that primarily interacts with neutrinos and contributes to the generation of neutrino masses and mixings through quantum loop corrections at the one-loop level. In this configuration, DM can solely annihilate into SM neutrinos without affecting the Cosmic Microwave Background anisotropies. We find that the rate of...
We utilize photon and charged meson fluxes at proton beam targets to produce long lived particles (LLPs) via scattering and decay mechanisms. These particles encompass light scalars and gauge bosons that appear in theories like extended Higgs sectors, $U(1)_{L_{\mu}-L_{\tau}}$, $U(1)_{T_{3R}}$ etc. We look at the sensitivities of the above in the context of experiments like ArgoNeuT,...
We study the cosmological signatures of a completely secluded dark sector consisting of axion-like particles (ALPs) with anomalous coupling to a dark Abelian gauge boson. The lighter ALP starts rolling during matter domination and produces dark photons through tachyonic instabilities. The resulting exponential growth in dark photon quanta sources tensor and scalar perturbations which are...
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and...
We studied the non-equilibrium dynamics of an axion-like particle (ALP) weakly coupled to a thermal bath and misaligned initial conditions. The ALP’s evolution is studied to leading order in the ALP coupling to the bath but to all orders in couplings among the bath’s degrees of freedom. Results are obtained using both Langevin equation derived from in-in formalism and quantum master equation,...
Curvatons are light (compared to Hubble during inflation) spectator fields that potentially contribute adiabatic curvature perturbations post-inflation. They can thereby alter CMB observables such as the spectral index $n_s$, the tensor-to-scalar ratio $r$, and the local non-Gaussianity $f_{\rm NL}^{\rm (loc)}$. We systematically explore the observable space of a curvaton with a quadratic...
Dark matter particles can form halos gravitationally bound to massive astrophysical objects. The Earth could have such a halo where depending on the particle mass, the halo either extends beyond the surface or is confined to the Earth's interior. We consider the possibility that if dark matter particles are coupled to neutrinos, then neutrino oscillations can be used to probe the Earth's dark...
Light primordial black holes(PBHs) form in the early universe through a variety of formation mechanisms. These PBHs can Hawking evaporate before BBN to produce SM particles and in our scenario also generate the dark matter(DM) relic abundance. High frequency gravitational waves in the MHz-GHz regime are produced during the formation of these light PBHs. In this talk I will present two...
In this talk I will first discuss how rotation-dominated galaxies can be used to constrain the size of solitons inside galaxy dark matter halos. I will discuss how this confronts the theoretical expectation, which leads to a robust constraint on the fraction of ultralight dark matter in a wide mass range from 10^{-24} eV to 10^{-20} eV. I will then discuss how this bound is affected by the...
Studies of entanglement and other quantum information measures at colliders have recently been proposed to probe fundamental interactions at high energies. Inspired by these results, we examine tau pair productions at both lepton and hadron colliders, to probe dimension-6 dipole operators in the Standard Model Effective Field Theory (SMEFT).
The SMEFT contributions are found to be sizable in...
We present an updated global SMEFT analysis in the Higgs and Electroweak sectors using the SFitter framework. We use a newly implemented marginalization procedure that allows comparison of Wilson coefficient results between profiling and marginalization methods. Marginalization is motivated by better scalability for high-dimensional analyses and provides faster numerical convergence compared...
Our research focuses on studying the heating mechanism of neutron stars through the capture of inelastic dark matter. Due to the high density of neutron stars, infalling dark matter particles are accelerated to relativistic speeds. To analyze the scattering between ultra-relativistic targets in the neutron star and quasi-relativistic infalling dark matter, we employ relativistic kinematics....
Various theories beyond the Standard Model predict new, long-lived particles with unique signatures which are difficult to reconstruct and for which estimating the background rates is also a challenge. Signatures from displaced and/or delayed decays anywhere from the inner detector to the muon spectrometer, as well as those of new particles with fractional or multiple values of the charge of...
Motivated by flavour symmetry models, one may construct theories based on a low-energy limit featuring lepton flavour triality that have the flavour-violating decays $\tau^\pm \to \mu^\pm \mu^\pm e^\mp$ and $\tau^\pm \to e^\pm e^\pm \mu^\mp$ as the main phenomenological signatures of BSM physics. These decay modes are expected to be probed in the near future with increased sensitivity by the...
The Gaia satellite is cataloging the astrometric properties of an unprecedented number of stars in the Milky Way with extraordinary precision. This provides a gateway for conducting extensive surveys of transient astrometric lensing events caused by dark compact objects. In this work, we establish a data analysis pipeline capable of searching for such events in the upcoming Gaia Data Release 4...
This study investigates the capture and thermalization of inelastic dark matter outside neutron stars. While the possibility of capture, thermalization and annihilation has been studied in some detail in the literature, this has assumed dark matter thermalizes to a trajectory lying inside neutron stars. I will show that some inelastic dark matter models imply thermalization timescales long...
We study the anomalous $t\bar{t}Z$ couplings in the $t\bar{t}Z$ production in leptonic final state at the $13$ TeV LHC. We use the polarizations of top quarks and $Z$ boson, two-body and three-body spin correlations among the top quarks and $Z$ boson, and the cross section to probe the anomalous couplings. We estimate one parameter and simultaneous limits on the couplings of the effective...
In this work, we study the status of negative coupling modifiers in extended Higgs sectors, focusing on the ratio of coupling modifiers that probes custodial symmetry violation $\lambda_{WZ} = \kappa_{W}/\kappa_{Z}$. Higgs sectors with multiplets larger than doublets are the only weakly coupled models that give tree-level modifications to $\lambda_{WZ}$, and we explore all such models allowed...
There exists a whole landscape of QCD axion models. However, if this particle is to make up the dark matter, the absence of catastrophic domain walls and exotic strongly interacting relics singles out two minimal versions of hadronic axions as the only viable possibilities. I argue that these models generically predict sizeable flavor-violating axion couplings to quarks that can be probed at...
Long-lived particles are a prime target of searches in current and upcoming LHC runs. In my talk, I will discuss a renormalizable theory that includes a heavy weak-singlet vectorlike lepton that decays into a long-lived pseudoscalar boson and a tau lepton. I will show that this can be the dominant decay mode of the vectorlike lepton provided the pseudoscalar couplings deviate from the case of...
When gravitational waves propagate through a medium with a changing equation of state, their spectrum distorts. A changing equation of state results from massive particles decoupling from the cosmic plasma as the temperature decreases. For low-frequency stochastic gravitational waves, this leads to deviations from the standard $k^3$ scaling. Interestingly, low-frequency waves emitted from...
Sterile neutrinos can be produced through mixing with active neutrinos in the hot and dense core of a collapsing supernova (SN). The standard SN bounds on the active-sterile mixing ($\theta$) arise from the SN1987A energy-loss argument. In this talk, I will discuss a novel and stringent bound on $\theta$ arising from the energy deposition through the decays of sterile neutrinos inside the SN envelope.
The top quark is hypothesized in many BSM models to have enhanced, non-standard or rare interactions with other SM or BSM particles. This presentation covers the latest CMS direct results in this regard, including the tests of lepton flavor violations and baryon number violations. It does not cover FCNC searches.
Ultralight axions and dark photons are compelling candidates for dark matter. In this talk, I will provide an overview of my recent work (arXiv:2207.05767, 2301.03622) on detecting radio-frequency axions and dark photons using radio telescopes. The detectability relies on two distinct underlying mechanisms. One mechanism involves local dark photon dark matter inducing harmonic oscillations of...
The Standard Model effective field theory (SMEFT) is a standard tool for parametrizing the effects of new physics. The ordiinary approach to SMEFT is to use the truncation at dimension-6, which would typically be the leading contribution beyond the Standard Model. We perform the matching to dimension-8 in the two-Higgs-doublet model (2HDM) and critically examine the dimension-6 and dimension-8...
Due to naturalness arguments we must continue our quest for CPV at all
frontiers. This is of course esp. so @ LHC. New experimental efforts with
additional expt. + theory inputs will be highlighted.
The minimum testable dark matter (DM) mass for almost all DM signatures in celestial bodies is determined by the rate at which DM evaporates. DM evaporation has previously been calculated assuming a competition between the gravitational potential of the object, and thermal kicks from the celestial-body matter. I will point out a new effect, where mediators with a range larger than the...
Pulsar binaries can be used for robust probes of new physics. There are two main reasons for this. First, there exists an abundance of high precision experimental data on orbital period decays of pulsar binaries. Second, pulsars are extreme astrophysical objects for which BSM effects can be significantly enhanced by large particle number densities. In my talk, I will discuss the use of pulsar...
The latest results from searches for electroweak production of SUSY particles with the CMS experiment will be presented. The analyses are based on the full dataset of pp collisions recorded at sqrt(s) = 13 TeV during the LHC Run 2. Searches are performed in multiple final states and the combination of those searches will be also discussed.
Searches for dark matter decaying into photons constrain its lifetime to be many orders of magnitude larger than the age of the Universe. A corollary statement is that the abundance of any particle that can decay into photons over cosmological timescales is constrained to be much smaller than the cold dark-matter density. We show that an irreducible freeze-in contribution to the relic density...
We introduce a mechanism by which a misaligned ALP can be dynamically converted into a dark photon in the presence of a background dark magnetic field. An abundance of non-relativistic ALPs will produce dark photons with momentum of order the inhomogeneities in the background field; therefore a highly homogeneous field will produce non-relativistic dark photons without relying on any...
Primordial black holes (PBHs) are a well motivated, macroscopic alternative to particle-like dark matter. If present in the early universe, PBHs will accrete matter, producing high energy photons. The injection of high energy photons during the Dark Ages affects the thermal and ionization histories of the universe, leading to noticeable impacts on the CMB power spectra. In this talk, I will...
We consider a model with a complex scalar field that couples to $(e,\mu)$ or $(\mu,\tau)$ within the ``longevity" window: $[|m_{l_1} - m_{l_2}|, m_{l_1} + m_{l_2}]$ in which $l_1$ and $l_2$ are the two different charged leptons. Within such a mass window, even a relatively large coupling ({\em e.g.} of the size commensurate with the current accuracy/discrepancy in the muon $g-2$ experiment)...
The nuclear processes within the sun could lead to the production of Beyond the Standard Model (BSM) particles of MeV scale. If these particles are long-lived, they could escape from the Sun and decay into observable particles en route to the Earth.
We use data available from the RHESSI Spectrometer to explore scenarios involving these solar long-lived particles. In particular, we...
A new paradigm for dark matter searches, allows to focus not only on the coupling between dark matter and the Standard Model, but also on the interactions between dark matter constituents themselves. The LHC is in a unique position to investigate such a rich dark sector which is otherwise difficult to probe with direct and indirect detection techniques. In this talk, a recently published...
Top Yukawa coupling is deeply connected to many fundamental puzzles in Higgs and Electroweak physics. In this study, we seek to measure the Top Yukawa coupling at the future high-energy muon colliders utilizing the Higgs unitarization in the $V_L V_L \rightarrow t\bar{t} $ process. If the Top Yukawa coupling
deviates from the Standard Model (SM) value, the amplitude of the
processes with...
We provide a comprehensive analysis of constraints on Supersymmetric gravitinos and axinos originating from spectral distortion, BBN and Lyman-alpha considerations. We analyze the current status and future prospects of such scenarios from cosmological probes. Furthermore, we provide the complementary constraints from collider data and assess the future discovery prospects.
Dark photons can oscillate into SM photons via kinetic mixing in a way that is analogous to neutrino oscillations. Much like the MSW effect for neutrinos in environments of varying density, the probability for dark photons to convert to photons depends on the properties of the ambient background (density, electromagnetic fields, etc.) Resonances are even possible when there is a level-crossing...
In this talk, I will motivate the study of models of dark radiation. Dark radiation models might have a rich phenomenology, with imprints on cosmological observables. Upcoming CMB and LSS measurements will be sensitive to different signals, which makes the exploration of Dark radiation imprints timely. Moreover, we recently showed that Dark radiation might be an asset in solving the Hubble and...
We present simulation of the dominant off-shell Higgs production mechanisms (gluon fusion, vector boson fusion, and associated production with a vector boson) with subsequent decay to two Z bosons. Effects of Effective Field Theory (EFT) operators on kinematic distributions are modeled for the signal and interfering background diagrams.
If a light axion is present during inflation and becomes part of dark matter afterwards, its quantum fluctuations contribute to dark matter isocurvature. In this article, we introduce a whole new suite of cosmological observables for axion isocurvature, which could help test the presence of axions, as well as its coupling to the inflaton and other heavy spectator fields during inflation such...
We summarize current results for searches of the production of supersymmtric particles decaying to photons in the final state using LHC data collected with the CMS detector. The latest results on a SUSY search with diphotons and large missing momentum as well as a stealth supersymmetry search involving diphotons and low missing momentum are presented.
In this presentation, I will explore the impact of finite top and bottom quark masses in the computation of scattering cross-sections for Higgs Boson production in association with three jets at Hadron Colliders like the CERN Large Hadron Collider. Additionally, I will offer insights into the expected outcomes for the production of a CP-violating Higgs.
We show how dark photons originating from an abelian Higgs model can be produced from the decay of the radial mode that acts as the curvaton, a light field during inflation that generates (part of) the adiabatic large scale cosmological primordial fluctuations.
Novel techniques, using trackless and delayed jet information combined in a deep neural network discriminator, can be employed to identify decays of long-lived particles. In this talk we present how such techniques could be exploited to search for long-lived particles decaying in the outer regions of the CMS silicon tracker or in the calorimeters. The results, obtained using the full Run-II...
In recent years, there has been renewed interest in the physics of axion strings since they naturally arise in axion models and can have a dramatic impact on cosmological observations. It is well- known that axion strings superconduct since massless chiral excitations can propagate along them. Aside from anomaly inflow, a common explanation for why these modes exist is that a bulk fermion...
The portal connecting the invisible and visible sectors is one of the most natural explanations of the dark world. However, the early-time dark matter production via the portal faces extremely stringent late-time constraints. To solve such tension, we construct the scalar-controlled kinetic mixing varying with the ultralight CP-even scalar's cosmological evolution. To realize this and...
We study the potential of DIS measurements at the Large Hadron-electron Collider (LHeC) and the Electron-Ion Collider (EIC) to probe physics beyond the Standard Model. Our study is performed in the context of the Standard Model Effective Field Theory (SMEFT). We find that future measurements at both machines can improve existing SMEFT fits to precision electroweak data by resolving blind spots...
Upcoming neutrino experiments are expected to detect the Diffuse Supernova Neutrino Background (DSNB). This requires pondering all possible sources of background. Sub-GeV dark matter (DM) which annihilates into neutrinos is a potential background that has not been considered so far. We simulate DSNB and DM signals, as well as backgrounds in the Hyper-Kamiokande detector. We find that...
Ultralight dark-photon dark matter coupled to the Standard Model (through e.g. $B$ or $B−L$ charges) would supply a new force that oscillates with a frequency set by the dark photon mass. Such forces result in fluctuations in the separation between inertial test masses, a physical quantity tracked in many gravitational-wave (GW) detectors. A recent GW detection proposal based on monitoring the...
Non-conventional signatures like exotic long-lived particles can naturally arise from many beyond-the-standard-model scenarios, which are closely connected to some of the most important puzzles in particle physics, including hierarchy problem, the nature of dark matter, the origin of neutrino mass, and the origin of matter-antimatter asymmetry. Searches for non-conventional signatures also...
The chromo-natural inflation (CNI) scenario predicts a potentially detectable chiral gravitational wave signal, generated by a Chern-Simons coupling between a rolling scalar axion field and an SU(2) gauge field with an isotropy-preserving classical background during inflation. However, the generation of this signal requires a very large integer Chern-Simons level, which can be challenging to...
We explore CP-violation in Higgs-top interactions via the semileptonic $pp \to t\bar{t}h$ channel with $h \to \gamma\gamma$ at the high luminosity LHC with machine learning-based unfolding techniques. We invert the event simulation chain, unfolding the detector-level events to construct and encode observables in their relevant partonic reference frame to improve CP sensitivity.
Searching for Higgs boson decays to four bottom quarks is a challenging and critical benchmark for LHC experiments. This final state is predicted by a variety of beyond the Standard Model theories, and current LHC searches focus on the associated production of a Higgs boson with a $W$ or $Z$ boson that subsequently decays to leptons which can be used for triggering. We evaluate the sensitivity...
In this talk, we will discuss about the results of searches for Higgs pair production in the four-bottom-quark final state via gluon fusion (ggF), vector boson fusion (VBF) and the one associated with an additional vector boson (VHH) with the CMS detector. In addition to the analysis strategy and limits on the production cross section of this process, constraints on the Higgs boson...
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus to within about an MeV to 100 TeV. Most of the stable constituents of known matter have masses in the lower range, and a thermal origin for dark matter works in a simple and predictive manner in this mass range as well....
Well-motivated scenarios of thermally-produced dark matter often result in a population of electrons and positrons within galaxies produced through dark matter annihilation -- often in association with high-energy gamma rays. As they diffuse through galactic magnetic fields, these $e^\pm$ produce synchrotron radio emission. The intensity and morphology of this signal depends on the properties...
I will present a novel search technique for axions with a CP-violating monopole coupling $\tilde{g}_{Q}$ to bulk SM charges $Q \in \{B,L,B-L\}$. Gradients in the static axion field configurations sourced by matter induce achromatic circular photon birefringence via the axion-photon coupling $g_{\phi \gamma}$. Circularly polarized light fed into an optical or (open) radio-frequency (RF)...
We take multiple boson production at high-energy muon colliders to probe the Higgs-muon coupling in the Standard Model Effective Feild Theory (SMEFT) and Higgs Effective Feild Theory (HEFT) framework.
Recently IceCube announced the observation of high-energy neutrinos from the active galaxy NGC 1068. Due to the potential for scattering between signal neutrinos and cosmic background neutrinos, this observation is sensitive to neutrino self-interactions mediated by a massive scalar. In this talk I will present bounds based on the data, highlight the role that detector physics plays in this...
Under supersymmetry (SUSY) models with low electroweak naturalness (natSUSY), which have been suggested to be the most likely version of SUSY to emerge from the string landscape, we examine the viabilities of future search for the heavy SUSY Higgs bosons H, A, H^\pm through various their decay signatures in LHC. The traditional H, A -> tautau, as well as H^\pm -> tau+nu, t+b, with a spectator...
We explore the possibility of resolving the $W$ mass shift observed by the CDF collaboration and the apparent deviation from unitarity in the first row of the CKM matrix simultaneously in a class of left-right symmetric models with universal seesaw. A unique non-trivial solution to the two anomalies was obtained, where the down quark mixing with vector-like quarks~(VLQ) resolves the CKM...
Stellar binaries have historically provided a rich target in the search for exotic compact objects such as primordial black holes (PBHs) or MACHOs. A sufficiently heavy compact object flying sufficiently close to a binary will disrupt or soften it, an effect that will show up in binary data as sparseness at large separation bins. While most studies have focused on the softening of wide...
Neutrinos allow us to probe the interiors of stars during core collapse, and detecting them can teach us about the different stages and processes in the collapse. To date, only 24 supernova neutrinos have been detected all originating from a single event, SN1987A. Since then, most studies have focused on two different distance regimes of supernovae neutrinos: Galactic/local events and all past...
