We describe a new scale-invariant jet clustering algorithm that does not impose a fixed cone size on a collider event. The proposed construction unifies large-radius jet finding, substructure axis-finding, and recursive filtering of soft wide-angle radiation into a single procedure. The sequential clustering measure history facilitates high-performance substructure tagging with a boosted...
Massive astrophysical compact halo objects have been proposed as possible constituents of dark matter today. The mass range of massive compact object DM candidates is quite extensive. Within the broad mass spectrum, the asteroid-mass window has recently received much attention, especially in relation to primordial black holes (PBHs). In this talk, I will first discuss the searches for...
Direct detection experiments around the world are searching for the small dark matter-nucleon interactions that would give us the first clue about its particle physics properties. If such interactions exist, they would also cause dark matter to become trapped inside stars. This can have consequences ranging from unobservable to catastrophic: small effects on neutrino fluxes detected at earth,...
The Sanford Underground Research Facility (SURF) has been operating for more than 15 years as an international facility dedicated to advancing compelling multidisciplinary underground scientific research in rare-process physics, as well as offering research opportunities in other disciplines. SURF laboratory facilities include a Surface Campus as well as campuses at the 4850-foot level (1500...
There are numerous motives (e.g., the baryon asymmetry problem) for considering baryon number violation (BNV) in extensions to the Standard Model. Given our current stringent constraints on BNV from certain experiments (e.g., SuperK), it is natural to examine the consequences of BNV in extreme conditions that are not realized terrestrially. In this talk, I show how the particle physics of BNV...
The possibility of dark matter residing in the neutrino sector remains of high interest, being probed by X-ray astronomy as well as laboratory searches. I will review candidate structure-formation and X-ray signals and constraints on keV-scale sterile neutrino dark matter. Much interest also remains at a factor of a million higher energy, with the Galactic Center Excess (GCE) of gamma-ray...
The direct capture and accumulation of Galactic dark matter in
astrophysical bodies can occur as a result of its scattering with nuclei. In this work we investigate the detailed capture and evaporation of dark matter in terrestrial planets, taking Earth as an example. We focus on the strongly interacting case in which Earth may be opaque to dark matter, referred to as the ``optically thick"...
Cosmic stasis is a phenomenon in which the abundances of multiple cosmological energy components — components such as matter, radiation, or vacuum energy — remain effectively constant despite the expansion of the universe. One mechanism which can give rise to an extended period of cosmic stasis is the evaporation of a population of primordial black holes (PBHs). In this talk, I review how PBH...
Axions and axion-like pseudoscalar particles with dimension-5 couplings to photons exhibit coherent Primakoff scattering with ordered crystals at keV energy scales, making for a natural detection technique in searches for solar axions. We find that there are large suppressive corrections, potentially greater than a factor of $\mathcal{O}(10^3)$, to the coherent enhancement when taking into...
We examine solar neutrinos in dark matter detectors including the effects of flavor-dependent radiative corrections to the CEνNS cross section. Working within a full three-flavor framework, and including matter effects within the Sun and Earth, detectors with thresholds ≲ 1 keV and exposures of ∼ 100 ton-year could identify contributions to the cross section beyond tree level. The differences...
We propose a new scenario of leptogenesis, which is triggered by a first-order phase transition (FOPT). The right-handed neutrinos (RHNs) are massless in the old vacuum, while they acquire a mass in the new vacuum bubbles, and the mass gap is huge compared with the FOPT temperature. The ultra-relativistic bubble walls sweep the RHNs into the bubbles, where the RHNs experience fast decay and...
In this work, we present UV completions of the recently proposed number-changing Co-SIMP freeze-out mechanism. In contrast to the standard cannibalistic-type dark matter picture that occurs entirely in the dark sector, the $3\to 2$ process setting the relic abundance in this case requires one Standard Model particle in the initial and final states. This prevents the dark sector from...
The past decades have seen an explosive growth in searches for axion dark matter, while its cosmological origin has been a theoretical puzzle. The conventional production is the misalignment mechanism, where the abundance arises from a field misalignment from the potential minimum. Nevertheless, this mechanism can naturally explain axion dark matter only in the limited parameter space where...
The neutrino oscillation needs parameters to be measured precisely to provide essential information for a modification of the Standard Model. Accomplishing this novel goal in future neutrino experiments requires high flux neutrino beams and powerful combination of near and far detectors. Fermilab’s PIP-II LINAC is an essential element in providing high flux protons to the Long Baseline...
We propose a novel mechanism of boosting dark matter by cosmic-ray neutrinos. The new mechanism is so significant that the arriving flux of cosmic-ray neutrino boosted dark matter (νBDM) lighter than O(1) MeV on Earth substantially larger than the one of the cosmic-ray electron boosted dark matter. Therefore, νBDM can dominantly contribute in direct detection experiments. We derive...
The Large Magellanic Cloud (LMC) can significantly impact the dark matter halo of the Milky Way, and boost the dark matter velocity distribution in the Solar neighborhood. Cosmological simulations that sample potential Milky Way formation histories are powerful tools, which can be used to characterize the signatures of the LMC's interaction with the Milky Way, and can provide crucial insight...
The Galactic center excess (GCE) remains one of the most intriguing discoveries from the Fermi Large Area Telescope (LAT) observations. I will revisit characteristics of the GCE tested under an updated set of high-resolution galactic diffuse gamma-ray emission templates. This diffuse emission, which accounts for the bulk of the observed gamma rays, is ultimately due to cosmic-ray interactions...
We present recent work on hidden sector model building based on particles with a continuous mass spectrum. In the past, these have been known as models with warped extra dimension, near-conformal field theories, hidden valleys, and unparticles. While these ideas saw a golden age as speculations for electroweak physics ahead of the LHC, they may find a new life in hidden sector physics. We...
Primordial black holes (PBHs) from the early Universe constitute an attractive non-particle dark matter (DM) candidate. I will present several generic mechanisms of PBH formation based on scalar fields, highlighting how astrophysical signatures of PBHs can help distinguish them. Intriguingly, microlensing observations could be pointing to first hints of PBHs associated with yet unexplored...
The TESSERACT collaboration will search for dark matter particles below the proton mass through interactions with two types of novel, ultra-sensitive detectors, These detectors, SPICE & HeRALD, aim to provide leading sensitivities to low mass dark matter candidates. The HeRALD experiment will use superfluid He4 as a target material, which is an ideal kinematic match for dark matter nuclear...
Coherent, elastic neutrino-nucleus scattering (CEvNS) is a low-Q2 neutrino interaction channel, with the neutrino transferring a small, but experimentally detectable, kinetic energy to the nucleus. The first measurement of CEvNS was achieved using the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory by the COHERENT experiment using a 14.6-kg CsI[Na] scintillation crystal. Due...
Neutrino experiments will have leading sensitivity to several dark matter and dark sector models. I discuss signals from a range of different dark sector models, from induced nucleon decay in mesogenesis models to production, scattering, and decay of dark sector states in neutrino beams. I present simulation tools for boosted dark matter and induced nucleon decay signals. I discuss some...
Neutrino emission from gravitational capture and subsequent annihilation of elastic dark matter in the Sun is largely constrained due to null results from direct-detection experiments. However, these limits are relaxed for inelastic dark matter. In this talk, we look at the sensitivity of a large volume detector, such as DUNE or Super-Kamiokande, to the neutrino flux originating from the Sun....
I will review existing hints and constraints on light sterile neutrinos. I will then explain the primary reasons why these anomalous data sets cannot be simply interpreted as a 1 eV sterile neutrino due to constraints from other experimental probes, notably solar neutrinos and cosmological data sets. I will present a novel, simple model that evades many of these constraints by adding in one...
We propose a novel scheme for performing a beam-dump-like experiment with the ATLAS/CMS detector. At the LHC, high-energy proton collisions result in jets containing a number of energetic hadrons/electromagnetic objects that are essentially "dumped" to HCAL/ECAL, inducing the production of secondary hadrons, electrons, and photons in calorimetric showers. We envision a situation where...
We analyze the expected sensitivity of current and near-future water(ice)-Cherenkov atmospheric neutrino experiments in the context of standard three-flavor neutrinos oscillations. In this first in-depth combined atmospheric neutrino analysis, we analyze the current shared systematic uncertainties arising from the shared flux and neutrino-water interactions. We then implement the systematic...
The neutrino data can’t be accommodated within the SM.
Origin of the observed Hierarchies between charged fermion masses and CKM matrix elements remain unexplained within the SM. Also the neutrino data can’t be accommodated and enough amount of the baryon asymmetry can’t be generated within the SM.
We consider simple extension by non-anomalous U(1) flavor symmetry, which gives natural...
In this talk, I will present Majorana neutrino mass models that yield predictions for lepton flavor violating processes that are testable in the near future. By tying the models to other observables beyond the SM, e.g., anomalies, dark matter, or baryogenesis, we obtain testable predictions for LFV that allow for falsification and goalposts for experimental sensitivities. In addition, I will...
We investigate the phenomenology of a non-thermal dark matter (DM) candidate in the context of flavor models that explain the hierarchy in the masses and mixings of quarks and leptons via the Froggatt-Nielsen (FN) mechanism. A flavor-dependent $U(1)_{FN}$ symmetry explains the fermion mass and mixing hierarchy, and also provides a mechanism for suppressed interactions of the DM, assumed to be...
In this talk, I will motivate and describe a few recent precise calculations of radiative corrections to neutrino oscillation and cross-section experiments. I will present elastic neutrino-electron, inverse muon decay cross sections, and neutrino energy spectra from radiative muon, pion, and kaon decays, with quantified uncertainties. I will formulate radiative corrections to charged-current...
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 arise from the SN1987A energy-loss argument. In this talk, I will discuss a novel and stringent bound on the mixing arising from the energy deposition through the decays of sterile neutrinos inside the SN envelope.
Carbon burning marks the ignition of the third nuclear fuel supply after H- and He-burning in the evolution of massive stars. Since the stellar core temperature is strongly correlated with the stellar mass, a minimum mass is required for carbon ignition. This critical mass limit, common referred to as $M_{up}$, depends on the reaction rate of the carbon fusion reactions. This parameter...
We propose a model to realize the lighter QCD axion. Exploiting the mirror sector, the minimum position of the total potential is still at origin which does not spoil the solution to the strong CP problem. The axion mass can be reduced by tuning the amplitude of the potential from the mirror sector. There are interesting phenomenology during the cosmological evolution history. The parameter...
Neutrino oscillation physics is a rich phenomenon, especially when any of the following is true: the neutrinos have low energy, the travel distance is large, and interactions with matter are significant along the path of propagation. All three of these criteria are met in low-energy atmospheric neutrino oscillations. I will demonstrate how this class of oscillations is exciting for several...
In this contribution I will talk about recent developments on searching for new physics with high-energy astrophysical neutrino sources.
Neutrino experiments at a proposed Forward Physics Facility (FPF) would collect neutrino and antineutrino interaction data from one million muon neutrinos, 100,000 electron neutrinos and 10,000 tau neutrinos in the High-Luminosity era of the Large Hadron Collider (LHC). Already during Run 3, the experiments FASERv and SND@LHC are installed and collecting data. In the forward region where...
We explore a novel possibility of light thermal dark matter within the context of neutrino mass models. In the sub-GeV mass regime, dark matter relic solely annihilates into neutrinos without affecting the Cosmic Microwave Background anisotropies. We have proposed a minimal UV-complete model for this scenario. All new physics states lie at or below the electroweak scale, affecting Higgs...
We probe dark matter-electron scattering using high-energy neutrino observations from the Sun. Dark matter (DM) interacting with electrons can get captured inside the Sun. These captured DM may annihilate to produce different Standard Model (SM) particles. Neutrinos produced from these SM states can be observed in IceCube and DeepCore. Although there is no excess of neutrinos from the Solar...
