Effective field theories are a very powerful mean to describe theories at energies well below a certain cutoff scale. However, not all points in the parameter space spanned by their coefficients allow for a UV completion that is both unitary and analytic, and various bounds have been derived in the literature. These bounds attain particular phenomenological relevance when applied to the...
Some New Physics scenarios that can explain the hints of Lepton Flavor Universality Violation (LFUV) observed in the B-meson decays also predict Lepton Flavor Violating (LFV) decay modes. We explore minimalistic scenarios involving leptoquark states at the $\mathcal{O}(\mathrm{TeV})$ scale which are consistent with low energy flavor physics observables. We show that the upper bound on LFV...
$SU(2)_L$-invariance links charged dilepton $\bar{q}\,q^\prime\,\bar{\ell}\,\ell$ and dineutrino $\bar{q}\,q^\prime\,\bar{\nu}\,\nu$ couplings.
This connection can be established using SMEFT and holds model-independently if only SM-like left-handed light neutrinos are present. This allows to perform complementary experimental tests of lepton universality and charged lepton flavour...
Higgs production in association with a photon at hadron colliders is a rare process, not yet observed at the LHC. We show that this process is sensitive to significant deviations of Higgs couplings to first and second generation SM quarks (particularly the up-type) from their SM values, and use a multivariate neural network analysis to derive the prospects of the High Luminosity LHC to probe...
We study an extended 2 Higgs doublet model (2HDM) in which the Standard Model (SM) Yukawa interactions are forbidden due to a global $U(1)^\prime$ symmetry, but may arise via mixing with vector-like families. In this model, the hierarchical structure of Yukawa couplings of quarks and leptons in the SM arises from the heavy masses of the fourth and fifth vector-like families. Within this model,...
In recent years particle physics research has undergone somewhat of a phase transition, looking increasingly towards hidden sectors and the feebly interacting frontier. In this talk I will introduce a new approach to parameterising dark sector forces, underpinned by the Källén-Lehman representation, in which the effects of any general scalar fifth force are captured by a single...
We apply on-shell amplitude techniques to the study of neutrino oscillations in vacuum, focussing on processes involving W bosons. We start by determining the 3-point amplitude involving one neutrino, one charged lepton and one W boson, highlighting all the allowed kinematic structures. The result we obtain contains terms generated at all orders in an expansion in the cutoff scale of the...
Neutrino oscillations occur due to non-zero masses and mixings and most importantly
they are believed to maintain quantum coherence even over astrophysical length scales. In the present study, we explore the quantumness of three flavour neutrino oscillations by studying the extent of violation of Leggett-Garg inequalities (LGI) if non-standard interactions are taken into account. We report an...
Current limits for the tau-neutrino transition magnetic moment to a sterile neutrino are far weaker than its electron and muon counterparts. In this poster/talk I discuss on-going work to investigate possible constraints on the transition magnetic moment between the tau neutrino and an O(MeV) sterile neutrino at DUNE: the proposed neutrino-beam experiment at FermiLab. I compare this with...
The simplest extension of the SM to account for the observed neutrino masses and mixings is the addition of at least two singlet fermions (or right-handed neutrinos). If their masses lie at or below the GeV scale, such new fermions would be produced in meson decays. Similarly, provided they are sufficiently heavy, their decay channels may involve mesons in the final state. Although the...
Type-II seesaw mechanism has been widely studied already as the link between neutrino mass generation beyond Standard Model (SM) and leptogenesis. In this study, the SM is minimally extended by two triplet Higgs scalars (with hypercharge $Y=2$), with one triplet having complex vacuum expectation value (vev) to impose generality. The triplet vevs are bounded by the $\rho$-parameter constraint...
The detection of Coherent Elastic Neutrino-Nucleus Scattering (CEʋNS) represents an experimental challenge because of its unique signature: a nuclear recoil with low energy in range of 10 to 100 eV on average.
This process, largely unexplored until today, could probe physics beyond the Standard Model such as non-standard neutrino interactions and electromagnetic form factors.
NUCLEUS is a...
The CUORE experiment is a ton-scale array of TeO$_2$ cryogenic bolometers located at the underground Gran Sasso National Laboratories, in Italy. The CUORE detector consists of 988 crystals operated as source and detector at a base temperature of $\sim$10 mK. The primary goal of CUORE is the search for neutrinoless double beta (0$\nu\beta\beta$) decay of $^{130}$Te, but thanks to its large...
The Cryogenic Underground Observatory for Rare Events (CUORE) experiment is an ongoing search for neutrinoless double beta decay located at the Gran Sasso National Laboratory (LNGS) in Italy. Recent work has found that the CUORE calorimeters are sensitive to acoustic and seismic events originating from outside the detector at LNGS. To measure the effect of these mechanical disturbances on the...
The exotic contributions of sfermions, neutralinos, and gluinos to neutrinoless double beta decay (0νββ) in the presence of R-parity violating (RPV) couplings have been known for some time. In this talk and poster, we update the sensitivity of 0νββ to the lightest mostly-bino neutralino over the neutralino mass range 0.1 MeV - 10 TeV, constraining the RPV coupling in a way that is compatible...
At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model ($\Lambda$CDM), the Planck collaboration reports $\sum m_\nu < 0.12\,\text{eV}$ at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable neutrinos, with lifetimes shorter than the age of the universe $\tau_\nu \leq t_U$,...
We consider a dark sector with multiple dark fermions interacting under a dark U(1) gauge interaction, mediated by a massless dark photon, with no kinetic mixing. Apart from this self interaction, a portal interaction, mediated by scalar messengers, exists between dark fermions and SM fermions. The species which contribute to the total matter relic density of the Universe, are the stable dark...
Belle II is a B-Factory experiment designed to produce precision measurements of CP violation in the weak sector as well as search for Beyond the Standard Model particle physics. The $e^{+}e^{-}$ collisions are created by the SuperKEKB accelerator which has achieved a world record of instantaneous luminosity of $2.4 \times 10^{34} {\text{cm}^{-2}}{\text{s}^{-1}}$. One of the highest priorities...
In light of the recent measurement of the anomalous muon magnetic moment which confirms a tension with the standard model, we revisit the light vector boson explanation of this discrepancy and show that there is still available parameter space in the context of models with co-annihilating dark matter or dark heavy neutral fermions. Reinterpreting the bounds from B factories with a semi-visible...
Massive photon-like particles are predicted in many extensions of the Standard Model as possible portals to a hidden sector where Dark Matter is secluded [1]. They are vector bosons mediating the interaction between ordinary and dark matter and can be produced in different processes through a feeble mixing to the photon. The PADME experiment [2], conducted at Laboratori Nazionali di Frascati...
In this talk I will discuss the possibility of obtaining a viable Dark Matter candidate in the context of a gauged, anomaly-free, flavor dependent U(1)' symmetry. I will discuss the relic density constraints, as well as the direct detection and neutrino physics input to the model. Possible detection at future experiments, such as SuperCDMS SNOLAB, is also considered.
In this talk I will give an overview of my research work on Accidental Dark Matter models. I briefly discuss some general aspects of Dark Matter model building and I show examples of specific models I have studied.
In this talk I discuss the viability of higgs portal majorana dark matter in light of current constraints, considering parameter ranges motivated by the thermal relic abundance and the potential GCE annihilation signal. Typically in these types of models, the mass of the dark matter is tuned so that annihilation occurs through the higgs resonance, in order to get a large enough annihilation...
The existence of a SM-neutral and light dark sector coupled to the visible sector via irrelevant portal interactions was considered in [$2012.08537$][1]. Such scenarios tend to be common in dark matter models arising as various extensions of the Standard Model.
The authors of $2012.08537$ use the conformal behaviour of this dark sector at energies $\Lambda_{IR} << E << \Lambda_{UV}$ to study...
In our work we study the cosmological phase transition (PT) in a conformal extension of the Standard Model (SM). The model considered is called SU(2)cSM, it extends the SM gauge group by an additional hidden SU(2)$_X$ gauge group, and a scalar doublet (whilist singlet under SM gauge group). The tree-level potential has no mass terms, all the masses are generated via the Coleman-Weinberg...
Unusual masses of black holes being discovered by gravitational wave experiments pose fundamental questions about the origin of these black holes. More interestingly, black holes with masses smaller than the Chandrasekhar limit ($\sim$ 1.4 $M_{\odot}$) are essentially impossible to produce through any standard stellar evolution. Primordial black holes, with fine-tuned parameters and with no...
I present the one-loop contributions to ALP-SM couplings stemming from effective ALP operators, including all finite corrections. The complete leading-order (dimension five) effective linear Lagrangian is considered. These corrections can become a useful tool to test ALP-SM interactions which are hard to measure via their loop impact on other observables that are more experimentally...
The theoretical calculation for pseudo--scalars hadronic decays $P \to M a$, with the Axion-Like-Particle escaping
the detection, is reviewed. While one-loop penguin contributions are usually considered, tree-level processes have
most often been overlooked in literature. Following the Brodsky/Lepage approach the tree-level contribution to the
ALP pseudo--scalar decay is estimated....
Pseudo-Nambu-Goldstone bosons (pNGBs) are attractive dark matter (DM) candidates since they are coupled to the Standard Model (SM) predominantly through derivative interactions. Thereby, they naturally evade the strong existing limits inferred from DM direct detection experiments. Working in an effective field theory that includes both derivative and non-derivative DM-SM operators, we perform...
In my talk and poster, I will motivate dark matter from composite Higgs models. In this framework, the dark matter candidate is a pseudo-Nambu Goldstone boson (pNGB) of a spontaneously broken symmetry, that lies naturally at the electroweak scale. In non-minimal scenarios, other pNGBs arise which can be lighter than the dark matter candidate and therefore affect its phenomenology significantly...
A fast-spinning axion can dominate the Universe at early times and generates the so-called kination era. The presence of kination imprints a smoking-gun spectral enhancement in the primordial gravitational-wave (GW) background. Current and future-planned GW observatories could constrain particle theories that generate the kination phase. Surprisingly, the viable parameter space allows for a...
The $\sigma_8$-tension of Planck data with weak lensing and redshift surveys is one of the main problems with the $\Lambda$CDM model of cosmology. We show that the tension can be alleviated by introducing an interaction between dark matter and neutrinos. We model the interaction using a linear Boltzmann treatment, introducing a novel implementation that for the first time uses the full massive...
I will present recent application of the SN 1987A cooling bound to set a constraint on dark flavored sectors. This is possible thanks to the fact that the protoneutron stars are hot and dense environments where hyperons can be efficiently produced. Therefore a decay of the form Λ→nX0, where X^0 is a new bosonic dark particle, will be severely constrained. I will explain the ingredients...
The reason why dwarf spheroidal and other galaxies appear to have a lower central density than predicted from N-body simulations based on LCDM cosmology is still an open question.
Apart from the possibility that baryonic physics could play a leading role in shaping the inner density profile of galaxies, the most popular new-physics explanation is to assume heat transfer caused by dark matter...
Could Dark Matter (DM) be made of Primordial Massive Black Holes (PMBHs) with such mass as detected by LIGO? The amplitude and frequency of gravitational microlensing can be used to detect PBHs. However, they can be mixed with the normal stellar population that can also contribute to microlensing. To separate the contributions from both populations, we perform numerical simulations to study...
Following theoretical (high-energy physics) considerations, we explore the possibility that our Universe contains a negative cosmological constant, dubbed $\lambda$, on top of an additional component $X$ accounting for the late-time accelerated stage of expansion. In this talk, I will present some of the cosmological implications of introducing $\lambda$. In particular, we will assess the...
