Baryon number violation (BNV) has been motivated by and studied in various extensions to the Standard Model. Observation of BNV in experiments would be a clear indication of new physics, which has not occurred so far. The high baryon density in neutron stars may enhance the rates of baryon number violating processes beyond those possible in terrestrial settings. Therefore, it is important to...
As the quantity of cosmological data grows, it becomes increasingly important to be able to accurately forecast the constraints those data can place on cosmological models, so that instrumental and computational time and resources can be used most effectively. Fisher forecasting, which uses the Fisher Information Matrix (FIM) to approximate the (negative) log-likelihood of a given model, is a...
A non-minimal dark sector could explain why WIMP dark matter has evaded detection so far. Based on the extensively studied example of a simplified t-channel dark matter model involving a colored mediator, we demonstrate that the Sommerfeld effect and bound state formation must be considered for an accurate prediction of the relic density and thus also when inferring the experimental...
The project proposes a search for a new source of CP Violation by studying a CP Violating Top Yukawa. The study is conducted through muon collisions at the proposed muon collider. Signal processes include $tth$, $tth\nu\nu$, and $tbh\mu\nu$ decaying semi-leptonically. Cross section dependence of signal processes with $\sqrt{s}$ and cross section dependence with varying CP-phase, $\alpha$, at...
We explore proton decay in a class of realistic supersymmetric flipped $SU(5)$ models supplemented by a $U(1)_R$ symmetry which plays an essential role in implementing hybrid inflation. Two distinct neutrino mass models, based on inverse seesaw and type I seesaw, are identified, with the latter arising from the breaking of $U(1)_R$ by nonrenormalizable superpotential terms. Depending on the...
The flat ΛCDM model of the Universe has started to falter due to recent and precise observations. One of the most promising models to resolve these problems is the axion-like Early Dark Energy (EDE) model. Our goal is to clarify how the EDE model and the shape of the Universe are simultaneously constrained with these recent datasets. We find that Early Dark Energy depends on shape only when...
Thermal friction offers a promising solution to the Hubble and the large-scale structure (LSS)
tensions. This additional friction acts on a scalar field in the early universe and extracts its energy
density into dark radiation, the cumulative effect being similar to that of an early dark energy (EDE)
scenario. The dark radiation automatically redshifts at the minimal necessary rate to...
In recent years the physics of Feebly Interacting Particles (FIPs) saw a growing interest as a possible solution to the Dark Matter issue [1]. FIPs are exotic and relatively light particles, not charged under the SM gauge group, whose interactions with the SM particles are extremely suppressed. They are assumed to be part of a possible secluded sector, called the dark sector, with the lightest...
The top quark spin information is highly correlated with the final state lepton polarization, making the dileptonic $t\bar{t}$ events good candidates to study quantum entanglement at the LHC. The $t\bar{t}$ momentum reconstruction is a key ingredient to accurately assessing such measurements. We will be comparing the strengths and weaknesses of different top-quark momentum reconstruction...
In the light of recent experimental results confirming a $4.2\sigma$ discrepancy in the measurement of $(g-2)_\mu$ and a possible $7\sigma$ excess in the $W$ boson mass, we propose a simple charged singlet extension of the Scotogenic model, the ScotoZee model, to investigate these anomalies while establishing a direct correlation with the neutrino oscillation data as well as the observed relic...
Modern precision measurements of the Hubble parameter H0 increasingly lay bare an accelerated expansion of the Universe beyond what is expected from Planck-LCDM analysis of the Cosmic Microwave Background (CMB). This H0-tension is here modeled by a non-local dark energy Λ=g(1-q)H^2, subject to the age of the Universe and the BAO inferred from globular clusters of the Milky Way and,...
We consider the model of heavy neutral leptons (HNLs) as an example to explore the potential of new physics searches at the Electron-Ion Collider (EIC). We propose two broad categories of search strategies depending on the HNL lifetime: direct searches for the prompt decay of HNLs with a short lifetime and displaced vertex searches for long-lived ones. After identifying the most promising...
In this talk, I shall describe how the recent high precision measurement of the $W$-boson mass by the CDF collaboration and the muon $(g-2)$ anomaly are correlated in the context of the two Higgs doublet model. The charged and neutral scalars of the model cannot be heavier than about 600 GeV for a simultaneous explanation of the two anomalies. The entire parameter space of the model can be...
We consider a simplified model where a quarkofobic W' is added to the standar model. This W' is considered to not couple or couple very feable to quarks, but in addition it couples to the standard model electroweak gauge bosons and leptons. We study the implications of such a new particle for the LHC and b-anomalies. We finally set limits from high energy searches that could be performed in...
Different evolution of the two dominant matter components of our Universe baryons and cold dark matter, due to the photon pressure before recombination, causes relative perturbations between the two fluids in the early Universe. These perturbations can be both in the density and peculiar velocity of the two fields and we call them relative baryon-CDM perturbations which are commonly neglected...
The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional...
Liquid xenon time projection chambers (LXe-TPCs) combine self-shielding, event position reconstruction, particle-type discrimination, and scalability to produce consistently world leading Weakly Interacting Massive Particle (WIMP) sensitivity. LUX-ZEPLIN (LZ) has the furthest physics reach of any xenon TPC built to date, however Rn222 chain Pb214 decays still represent the largest background...
The $R_{D(∗)}$ anomaly represents a tension with the lepton flavor universality. With recent data, the anomaly has a statistical significance greater than $3\sigma$ between BaBar, LHCb and Belle observatons. Many theoretical models were proposed to solve such difference between the theory and experiments. In the work we have done, we explore the phenomenology of 3 different models that could...
Dark matter (DM) characteristics can be explored via indirect detection through the observations of astrophysical objects which have captured DM. In this paper we analyze the role of stellar velocity on multiscatter DM capture rates. The addition of the stellar velocity with respect to its surrounding DM halo induces a suppression of this capture rate. We develop and validate an analytical...
We propose a program at B-factories of inclusive, multi-track displaced vertex searches, which are expected to be low background and give excellent sensitivity to non-minimal hidden sectors. Multi-particle hidden sectors often include long-lived particles (LLPs) which result from approximate symmetries, and we classify the possible decays of GeV-scale LLPs in an effective field theory...
Effects of A Hidden Sector on the Matter Power Spectrum
The absence of dark matter signals in direct detection experiments and collider searches has prompted interest in models in which dark matter belongs to a hidden sector minimally coupled to the Standard Model. In these scenarios, a long-lived massive particle might come to dominate the energy density of the early universe...
The Belle II experiment at the SuperKEKB energy-asymmetric e+e− collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. The design luminosity of the machine is 6×1035 cm−2s−1 and the Belle II experiment aims to ultimately record 50 ab−1 of data, a factor of 50 more than its predecessor. With this data set, Belle II will be able to measure the...
The presence of light thermally coupled dark matter affects early expansion history and production of light elements during the Big Bang Nucleosynthesis. Specifically, dark matter that annihilates into Standard Model particles can modify the effective number of light species in the universe Neff , as well as the abundance of light elements created buring BBN. These quantities in turn affect...
Experiments using proton beams at high luminosity colliders and fixed-target facilities provide impressive sensitivity to new light weakly coupled degrees of freedom. We revisit the production of dark vectors and scalars via proton bremsstrahlung for a range of beam energies, including those relevant for the proposed Forward Physics Facility (FPF) at the High Luminosity LHC, and upgraded...
In this talk, I will evaluate the potential for gravitational-wave (GW) detection in the frequency band from 10 nHz to 1 $\mu$Hz using extremely high-precision astrometry of a small number of stars. In particular, I will argue that non-magnetic, photometrically stable hot white dwarfs (WD) located at $\sim$ kpc distances may be optimal targets for this approach. Previous studies of astrometric...
When a burst of neutrinos from a core-collapse supernova (CCSN) passes by the Earth, it causes a permanent change in the local space-time metric, called the gravitational wave (GW) memory. Long considered unobservable, this effect will be detectable in the near future, at deci-Hertz GW interferometers. I will present a novel idea, where observations of the neutrino GW memory from CCSNe will...
Cosmic rays colliding with the atmosphere have historically played a central role in exploration of neutrinos, leading to discovery of neutrino oscillations with Super-Kamiokande experiment. As I will show, the ''atmospheric collider'' offers unprecedented novel opportunities for exploration of fundamental physics. I will present leading new searches for magnetic monopoles, as well as...
Sterile neutrinos at the GeV scale can resolve several outstanding problems of the Standard Model (SM), such as the source of neutrino masses and the origin of the baryon asymmetry through freeze-in leptogenesis, but they can be challenging to detect experimentally due to their small couplings to SM particles. In extensions of the SM with new interactions of the sterile neutrinos, they can be...
I will discuss gravitational waves (GWs) induced by a heavy spectator field that starts to oscillate during inflation. During the oscillation of the spectator field, its effective mass can also oscillate in some potentials. This mass oscillation can resonantly amplify the spectator field fluctuations. I will show that these amplified fluctuations can induce large GWs, which could be...
Sterile neutrinos with keV-scale masses are popular candidates for warm dark matter. In the most straightforward case they are produced via oscillations with active neutrinos. We introduce all types of effective self-interactions of active neutrinos and investigate the effect on the parameter space of sterile neutrino mass and mixing. Our focus is on mixing with electron neutrinos, which is...
Beyond the Standard Model (BSM) interactions in the neutrino sector have been of much interest in cosmology and astroparticle physics. We developed a Monte Carlo code to investigate the neutrino time delay distribution caused by BSM interactions en route to the observer. While we find excellent agreement for small optical depths, the optically thick limit show features that are not described...
The search for additional CP-violating interactions generated by BSM physics motivates a strong experimental effort to measure the neutron electric dipole moment (nEDM). The nEDM@SNS experiment planned at the Spallation Neutron Source at Oak Ridge National Laboratory aims to achieve a sensitivity of $2−3×10^{−28}$ e-cm, an improvement upon the current limit of $1x10^{-26}$ e-cm. This is...
The study of particle dark matter is of a dramatic importance in both fields particle physics and modern cosmology. It plays a profound rule in understanding the deep structure of nature. However, an abundance of multi-component dark matter models have been studied and investigated over the last decade. And since nature seeks simplicity we choose to review the simplest models and present new...
We propose a novel probe of weakly interacting massive particle (WIMP) dark matter (DM) candidates of a wide mass range which fall short of the required annihilation rates to satisfy correct thermal relic abundance, dubbed as "Miracle-less WIMP". If the DM interactions are mediated by an Abelian gauge boson like B-L, its annihilation rates typically remain smaller than the WIMP ballpark for...
We propose to use an elongated rectangular waveguide near its cutoff frequency to speed up axionic dark matter searches. The detector's large surface area increases the signal power, while its narrow transverse dimension and tapered-waveguide coupling suppress parasitic modes. The proposed system can fit inside a solenoid magnet and detect the QCD-axion at the axion mass $40-400\,\mu$eV. We...
A Friedmann-Robertson-Walker spacetime with contents dominated by a gas of tachyonic particles undergoes expansion with inflection (cosmic jerk) and acceleration similar, but not identical, to that of dark-energy-dominated models. The testing of such a tachyonic model against observation, as an alternative to the standard model, is under way. Fitting the model to redshift and distance data...
Low scale leptogenesis scenarios are difficult to verify due to our inability to relate the parameters involved in the early universe processes with the low energy or collider observables. Here we show that one can in principle relate the parameters giving rise to the transient CP violating phase involved in leptogenesis with those that can be deduced from the observation of electric dipole...
Solutions to the $\mu$ problem in supersymmetry based on the Kim-Nilles mechanism naturally feature a Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) axion with decay constant of order the geometric mean of the Planck and TeV scales, consistent with astrophysical limits. We investigate minimal models of this type with two gauge-singlet fields that break a Peccei-Quinn symmetry, and extensions with...
Inflationary models that are capable of matching observational constraints are abundant, but very few have an underlying physical principle guiding the choice of the inflaton potential and dynamics. We show how a recently developed model of gravity which incorporates an extension of general relativity to include projective invariance (TW gravity) naturally gives rise to a field acting as the...
We discuss the cosmology and phenomenology of freeze-in baryogenesis via dark-matter oscillations, focusing mainly on the case in which the dark matter couples to Standard Model leptons. We investigate viable models both with and without a Z_2 symmetry under which all new fields are charged, highlighting scenarios in which the baryon asymmetry is parametrically distinct from and enhanced...
The Thomas-Whitehead projective gravity theory has its origins in string theory. There is an identified correspondence between the coadjoint elements of the Virasoro algebra and Sturm-Liouville operators. This identification of the projective structure in one dimension allows for relating the Virasoro algebra and projective geometry in higher dimensions. The coadjoint orbits of Virasoro...
Stars that pass close to the supermassive black holes located in the center of galaxies can be violently disrupted by tidal forces, leading to flares that are observed as bright transient events in sky surveys. The rate for these events to occur depends on the black hole spins, which in turn can be affected by ultra-light bosons due to superradiance. In this talk, I will show that searches for...
We show how trinification models based on the gauge group $SU(3)_C \times SU(3)_L \times SU(3)_R$ realized near the TeV scale can provide naturally a variety of dark matter (DM) candidates. These models contain a discrete $T$ parity which may remain unbroken even after spontaneous symmetry breaking. The lightest $T$-odd particle, which could be a fermion, a scalar, or a gauge boson, can...
One of the main challenges in numerical cosmology is the difficulty of producing large scale, high resolution simulation data, especially when exploring novel cosmological models. Producing physical simulations on cosmological scales with enough detail to resolve galaxy-formation scale physics is very computationally expensive. In this work, I train a generative adversarial network (GAN) to...
We study in detail the viability and the patterns of a strong first-order electroweak phase transition as a prerequisite to electroweak baryogenesis in the framework of $Z_3$-invariant Next-to-Minimal Supersymmetric Standard Model (NMSSM), in the light of recent experimental results from the Higgs sector, dark matter (DM) searches and those from the searches of the lighter chargino and...
We study the possible searches at colliders using Vector Boson Fusion topology in the context of Simplified Models signatures. We examine the possible physics reach of these searches with regard to monojet-type searches, and determine how these two signatures are complementary. We determine the generic characteristics for dark matter signatures in the LHC if the underlying physics imply Vector...
