Related papers: Enhanced sensitivity to variation of $m_{e}/m_{p}$…
Recently, the CMS Collaboration performed a search on a new resonance decaying to $e^\pm\mu^\mp$ in the mass range of 110 GeV to 160 GeV. The search also hints a possible excess at 146 GeV with a $3.8\sigma~(2.8\sigma)$ of local (global)…
Asymptotic levels of the A $^1\Sigma_u^+$ state of the two isotopomers $^{39}{\rm K}_2$ and $^{39}{\rm K}^{41}{\rm K}$ up to the dissociation limit are investigated with a Doppler-free high resolution laser-spectroscopic experiment in a…
Precision spectroscopy of atoms and molecules allows one to search for and to put stringent limits on the variation of fundamental constants. These experiments are typically interpreted in terms of variations of the fine structure constant…
The Mu3e experiment aims to search for the lepton-flavour violating decay $\mu^+\rightarrow\ \text{e}^+ \text{e}^+ \text{e}^-$ with a sensitivity to one signal decay in $10^{16}$ muon decays at a muon stopping rate of $2\times 10^9…
We present the first detailed computation of the conversion of a bound muon into an electron mediated by a doubly charged $SU(2)$ singlet scalar. Although such particles are not too exotic, up to now their contribution to $\mu$-$e$…
We demonstrate that a near-dissociation photoassociation resonance can be used to create a deeply bound molecular sample of ultracold NaCs. To probe the resulting vibrational distribution of the sample, we use a new technique that can be…
Atomically thin MoS$_{2}$ crystals have been recognized as a quasi-2D semiconductor with remarkable physics properties. This letter reports our Raman scattering measurements on multilayer and monolayer MoS$_{2}$, especially in the…
An approximation that is often used in fits to reactor and atmospheric neutrino data and in some studies of future neutrino oscillation experiments is to assume one dominant scale, $\Delta m^2$, of neutrino mass squared differences, in…
We investigate electron-phonon coupling in the molecular crystals CH$_4$, NH$_3$, H$_2$O, and HF, using first-principles quantum mechanical calculations. We find vibrational corrections to the electronic band gaps at zero temperature of…
The difference in proton radii measured with $\mu p$ atoms and with $ep$ atoms and scattering remains an unexplained puzzle. The PSI MUSE proposal is to measure $\mu p$ and $e p$ scattering in the same experiment at the same time. The…
We have measured invariant mass spectra of electron-positron pairs in the target rapidity region of 12GeV p+A reactions. We have observed a significant difference in the mass spectra below the $\omega$ meson between p+C and p+Cu…
Carbon monoxide (CO) absorption in the sub-damped Lyman-$\alpha$ absorber at redshift $z_{abs} \simeq 2.69$, toward the background quasar SDSS J123714.60+064759.5 (J1237+0647), was investigated for the first time in order to search for a…
Two dimensional materials and their heterostructures constitute a promising platform to study correlated electronic states as well as many body physics of excitons. Here, we present experiments that unite these hitherto separate efforts and…
For the case of small matter effects: $V \ll \Delta m^2/2E$, where $V$ is the matter potential, we develop the perturbation theory using $\epsilon \equiv 2VE/\Delta m^2$ as the expansion parameter. We derive simple and physically…
The optical hybridization of the electronic states in strongly coupled molecule-cavity systems have revealed unique properties such as lasing, room temperature polariton condensation, and the modification of excited electronic landscapes…
The mass sensitivity of the vibration-rotation-inversion transitions of H$_3{}^{16}$O$^+$, H$_3{}^{18}$O$^+$, and D$_3{}^{16}$O$^+$ is investigated variationally using the nuclear motion program TROVE~\citep{TROVE:2007}. The calculations…
We study various properties of the vibrational normal modes for Coulomb-interacting particles in two-dimensional irregular confinement using numerical simulations. By analyzing the participation ratio and spectral statistics, we…
The very high precision of current measurements and theory predictions of spectral lines in few-electron atoms allows to efficiently probe the existence of exotic forces between electrons, neutrons and protons. We investigate the…
Axion-like particles and similar new pseudoscalar as well as vector bosons coupled to nucleons and electrons are predicted to lead to spin-dependent forces in atoms and ions. We argue that hyperfine structure measurements in hydrogen- and…
Parity-violating differences in rotational constants of a chiral 5d transition metal complex, that was previously experimentally well-characterised by broad-band microwave spectroscopy, are predicted with a recently established efficient…