Related papers: Precision Measurement of Transition Matrix Element…
High-resolution collinear laser spectroscopy of neutron-rich actinium has been performed at TRIUMF's isotope separator and accelerator facility ISAC. By probing the $7s^2~^1S_0$ $\rightarrow$ $6d7p~^1P_1$ ionic transition, the hyperfine…
We propose a compact atomic clock based on ultracold Rb atoms that are magnetically trapped near the surface of an atom microchip. An interrogation scheme that combines electromagnetically-induced transparency (EIT) with Ramsey's method of…
The first measurement of the magnitude of the CKM quark mixing matrix element $|V_{cb}|$ using on-shell $W$-boson decays is presented. The measurement is made with $t\bar{t}$ events from $pp$ collision data corresponding to an integrated…
We present measurements of Stark interference in the 6$^1S_0$ $\rightarrow$ 6$^3P_1$ transition in $^{199}$Hg, a process whereby a static electric field $E$ mixes magnetic dipole and electric quadrupole couplings into an electric dipole…
We present a method to precisly measure the frequencies of transitions to high-$n$ Rydberg states of the hydrogen atom which are not subject to uncontrolled systematic shifts caused by stray electric fields. The method consists in recording…
Precision measurement of small separations between two atoms or molecules has been of interest since the early days of science. Here, we discuss a scheme which yields spatial information on a system of two identical atoms placed in a…
Applying large magnetic fields to gain access to the hyperfine Paschen-Back regime can isolate three-level systems in a hot alkali metal vapors, thereby simplifying usually complex atom-light interactions. We use this method to make the…
The absolute frequency of the In$^{+}$ $5s^{2 1}S_{0}$ - $5s5p^{3}P_{0}$ clock transition at 237 nm was measured with an accuracy of 1.8 parts in $10^{13}$. Using a phase-coherent frequency chain, we compared the $^{1}S_{0}$ - $^{3}P_{0}$…
Direct frequency-comb spectroscopy is used to probe the absolute frequencies of $6S_{1/2}$-$8S_{1/2}$ two-photon transitions of atomic cesium in hot vapor environment. By utilizing the coherent control method of temporally splitting the…
Absolute normalisation of the LHC measurements with O(1%) precision and their relative normalisation, for the data collected at variable centre-of-mass energies, or for variable beam particle species, with O(0.1%) precision is crucial for…
The 5S$\to$6P transition in Rubidium (Rb) at 420 nm offers the advantage of a narrower linewidth and diverse applications in quantum technologies. However, the direct spectroscopy at this transition is challenging due to its weak transition…
An overview is presented of the measurements of the top quark mass performed by the ATLAS experiment at the LHC with an integrated luminosity varying between 35 pb$^{-1}$ and 4.7 fb$^{-1}$. Different techniques are used to measure the top…
The ratio of the off-diagonal hyperfine amplitude to the tensor transition polarizability (Mhf/beta) for the 6S-7S transition in cesium has been measured. The value of beta=27.024(43)(expt)(67)(theory)a_0^3 is then obtained using an…
The state-of-the-art miniature atomic clocks (MACs) are based on the phenomenon of coherent population trapping (CPT) in alkali-metal atomic vapors (Rb or Cs). Increasing frequency stability of the clocks is an urgent issue that will lead…
Matrix elements of six-quark operators are needed to extract new physics constraints from experimental searches for neutron-antineutron oscillations. This work presents in detail the first lattice quantum chromodynamics calculations of the…
Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the…
Positronium and muonium, as purely leptonic atoms without internal structure, provide ideal systems for high-precision tests of quantum electrodynamics (QED) and measurements of fundamental constants. However, the high velocities of these…
We experimentally demonstrate background-free, hyperfine-level-selective measurements of individual Cs atoms by simultaneous cooling to $5.3~\mu\rm K$ and imaging on the $6s_{1/2}\rightarrow 5d_{5/2}$ electric-quadrupole transition. We…
We measure the absolute absorption cross section of molecules using a matter-wave interferometer. A nanostructured density distribution is imprinted onto a dilute molecular beam through quantum interference. As the beam crosses the light…
We report on hyperfine-resolved spectroscopic measurements of the electric-dipole forbidden 5$p_{3/2} \to 8p_{1/2}$ transition in a sample of ultracold $^{87}$Rb atoms. The hyperfine selection rules enable the weak magnetic-dipole (M1)…