Constraining CP Violating Nucleon-Nucleon Long-Range Interactions in Diatomic eEDM Searches.

The searches for CP violating effects in diatomic molecules, such as HfF^{+} and ThO, are typically interpreted as a probe of the electron's electric dipole moment (eEDM), a new electron-nucleon interaction, and a new electron-electron interaction. However, in the case of a nonvanishing nuclear spin, a new CP violating nucleon-nucleon long-range force will also affect the measurement, providing a new interpretation of the eEDM experimental results. Here, we use the HfF^{+} eEDM search and derive a new bound on this hypothetical interaction, which is the most stringent from terrestrial experiments in the 1 eV-10 keV mass range.

Self-Consistent Extraction of Spectroscopic Bounds on Light New Physics.

Fundamental physical constants are determined from a collection of precision measurements of elementary particles, atoms, and molecules. This is usually done under the assumption of the standard model (SM) of particle physics. Allowing for light new physics (NP) beyond the SM modifies the extraction of fundamental physical constants.

New physics searches at kaon and hyperon factories.

Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the availability of very large datasets. On the other hand, useful complementary information is provided by hyperon decay measurements.

Towards an Independent Determination of Muon g-2 from Muonium Spectroscopy.

We show that muonium spectroscopy in the coming years can reach a precision high enough to determine the anomalous magnetic moment of the muon below one part per million (ppm). Such an independent determination of muon g-2 would certainly shed light on the ∼2  ppm difference currently observed between spin-precession measurements and (R-ratio based) standard model predictions. The magnetic dipole interaction between electrons and (anti)muons bound in muonium gives rise to a hyperfine splitting (HFS) of the ground state which is sensitive to the muon anomalous magnetic moment.

New Physics Implications of Recent Search for K_{L}→π^{0}νν[over ¯] at KOTO.

The KOTO experiment recently reported four candidate events in the signal region of K_{L}→π^{0}νν[over ¯] search, where the standard model only expects 0.10±0.02 events.

Photoproduction of Axionlike Particles.

We explore the sensitivity of photon-beam experiments to axionlike particles (ALPs) with QCD-scale masses whose dominant coupling to the standard model is either to photons or gluons. We introduce a novel data-driven method that eliminates the need for knowledge of nuclear form factors or the photon-beam flux when considering coherent Primakoff production off a nuclear target, and show that data collected by the PrimEx experiment in 2004 could improve the sensitivity to ALPs with 0.03≲m_{a}≲0.

Probing Axionlike Particles and the Axiverse with Superconducting Radio-Frequency Cavities.

Axionlike particles (ALPs) with couplings to electromagnetism have long been postulated as extensions to the standard model. String theory predicts an "axiverse" of many light axions, some of which may make up the dark matter in the Universe and/or solve the strong CP problem. We propose a new experiment using superconducting radio-frequency (SRF) cavities which is sensitive to light ALPs independent of their contribution to the cosmic dark matter density.

Coupling QCD-Scale Axionlike Particles to Gluons.

We present a novel data-driven method for determining the hadronic interaction strengths of axionlike particles (ALPs) with QCD-scale masses. Using our method, it is possible to calculate the hadronic production and decay rates of ALPs, along with many of the largest ALP decay rates to exclusive final states. To illustrate the impact on QCD-scale ALP phenomenology, we consider the scenario where the ALP-gluon coupling is dominant over the ALP coupling to photons, electroweak bosons, and all fermions for m_{π}≲m_{a}≲3  GeV.

Probing New Long-Range Interactions by Isotope Shift Spectroscopy.

We explore a method to probe new long- and intermediate-range interactions using precision atomic isotope shift spectroscopy. We develop a formalism to interpret linear King plots as bounds on new physics with minimal theory inputs. We focus only on bounding the new physics contributions that can be calculated independently of the standard model nuclear effects.

γ-ray Constraints on Decaying Dark Matter and Implications for IceCube.

Utilizing the Fermi measurement of the γ-ray spectrum toward the Inner Galaxy, we derive some of the strongest constraints to date on the dark matter (DM) lifetime in the mass range from hundreds of MeV to above an EeV. Our profile-likelihood-based analysis relies on 413 weeks of Fermi Pass 8 data from 200 MeV to 2 TeV, along with up-to-date models for diffuse γ-ray emission within the Milky Way. We model Galactic and extragalactic DM decay and include contributions to the DM-induced γ-ray flux resulting from both primary emission and inverse-Compton scattering of primary electrons and positrons.

Proposed Inclusive Dark Photon Search at LHCb.

We propose an inclusive search for dark photons A^{'} at the LHCb experiment based on both prompt and displaced dimuon resonances. Because the couplings of the dark photon are inherited from the photon via kinetic mixing, the dark photon A^{'}→μ^{+}μ^{-} rate can be directly inferred from the off-shell photon γ^{*}→μ^{+}μ^{-} rate, making this a fully data-driven search. For run 3 of the LHC, we estimate that LHCb will have sensitivity to large regions of the unexplored dark-photon parameter space, especially in the 210-520 MeV and 10-40 GeV mass ranges.

Exclusive window onto Higgs Yukawa couplings.

We show that both flavor-conserving and flavor-violating Yukawa couplings of the Higgs boson to first- and second-generation quarks can be probed by measuring rare decays of the form h→MV, where M denotes a vector meson and V indicates either γ, W or Z. We calculate the branching ratios for these processes in both the standard model and its possible extensions. We discuss the experimental prospects for their observation.

Top B physics at the LHC.

In top-pair events where at least one of the tops decays semileptonically, the identification of the lepton charge allows us to tag not only the top quark charge but also that of the subsequent b quark. In cases where the b also decays semileptonically, the charge of the two leptons can be used to probe CP violation in heavy flavor mixing and decays. This strategy to measure CP violation is independent of those adopted so far in experiments, and can already constrain non standard model sources of CP violation with current and near future LHC data.