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There exist multiple ways to cool neutral molecules. A front runner is the technique of buffer gas cooling, where momentum-changing collisions with abundant cold noble-gas atoms cool the molecules. This approach can, in principle, produce the most diverse
Jeremy Glick, William Huntington, Michael Borysow, Daniel Heinzen, Jacek Klos, Eite Tiesinga
We present three-dimensional Monte-Carlo simulations of the capture of 1000 K 7Li or 500 K 87Rb atoms by a continuous supersonic 4He jet and show that intense alkali-metal beams form with narrow transverse and longitudinal velocity distributions. The
Molecules have vibrational, rotational, spin-orbit and hyperfine degrees of freedom or quantum states, each of which responds in a unique fashion to external electromagnetic radiation. The control over superpositions of these quantum states is key to
Daniel Barker, James A. Fedchak, Jacek Klos, Julia Scherschligt, Abrar Sheikh, Eite Tiesinga, Stephen Eckel
We present measurements of thermalized collisional rate coefficients for ultra-cold $^7$Li and $^87}$Rb colliding with room-temperature He, Ne, N$_2$, Ar, Kr, and Xe. In our experiments, a combined flowmeter and dynamic expansion system, a vacuum metrology
Daniel Barker, Bishnu Acharya, James A. Fedchak, Nikolai Klimov, Eric Norrgard, Julia Scherschligt, Eite Tiesinga, Stephen Eckel
We describe the cold-atom vacuum standards (CAVS) under development at the National Institute of Standards and Technology. The CAVS measures pressure in the ultra-high and extreme-high vacuum regimes by measuring the loss rate of sub-millikelvin sensor
Lucas Ehinger, Bishnu Acharya, Daniel Barker, James A. Fedchak, Julia Scherschligt, Eite Tiesinga, Stephen Eckel
We compare the vacuum measured by two portable cold atom vacuum standards (pCAVS) based on ultracold $^7$Li atoms. Our pCAVS devices share the same laser system and measure the vacuum concurrently. The two pCAVS together detected a leak with a rate on the
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We found an error in our computation of the thermally averaged total rate coefficients for the collision of a room-temperature hydrogen dimer H$_2$ with an ultra-cold lithium sensor atom. We incorrectly accounted for the nuclear spin degeneracy and omitted
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We have found an error in the computation of the thermally-averaged total elastic rate coefficient for the collision of a room-temperature helium atom with an ultra-cold lithium atom presented. We omitted the factor $2/\sqrt\pi}$ in the normalization over
Jacek Klos, Hui Li, Eite Tiesinga, Svetlana Kotochigova
Molecules with unstable isotopes often contain heavy and deformed nuclei and thus possess a high sensitivity to parity-violating effects, such as Schiff moments. Currently the best limits on Schiff moments are set with diamagnetic atoms. Polar molecules
Eite Tiesinga, Peter J. Mohr, David B. Newell, Barry N. Taylor
We report the 2018 self-consistent values of constants and conversion factors of physics and chemistry recommended by the Committee on Data of the International Science Council (CODATA). The recommended values can also be found at physics.nist.gov
Daniel Barker, Nikolai Klimov, Eite Tiesinga, James A. Fedchak, Julia Scherschligt, Stephen Eckel
We present our progress towards a comparison of NIST's cold atom primary vacuum standard and a dynamic expansion vacuum standard. The cold atom vacuum standard (CAVS) converts the loss rate of atoms from a magnetic trap to a vacuum pressure using ab initio
Eite Tiesinga, Jacek Klos, Ming Li, Alexander Petrov, Svetlana Kotochigova
The electronic structure of magnetic lanthanide atoms is fascinating from a fundamental perspective. They have electrons in a submerged open 4f shell lying beneath a filled 6s shell with strong relativistic correlations leading to a large magnetic moment
Eite Tiesinga, Peter Mohr, David B. Newell, Barry Taylor
We report the 2018 self-consistent values of constants and conversion factors of physics and chemistry recommended by the Committee on Data of the Interna- tional Science Council (CODATA). The recommended values can also be found at physics.nist.gov
Within the Hartree atomic unit systems, the Schrödinger equation becomes parameter free. But there's more to it than making a student's life easier, as Gordon Drake and Eite Tiesinga recount.
Aliana Green, Hui Li, Jun Hui See Toh, Xinxin Tang, Katherine McCormick, Ming Li, Eite Tiesinga, Svetlana Kotochigova, Subhadeep Gupta
We report on observations and modeling of interspecies magnetic Feshbach resonances in dilute ultracold mixtures of open-shell alkali-metal 6 Li and closed-shell 173 Yb atoms with temperatures just above quantum degeneracy for both fermionic species
This publication is a colorful poster illustrating the relationships of the International System of Units (SI) derived units with special names and symbols and the seven traditional base units. The diagram is aligned with the BIPM SI Brochure, 9th edition
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We have computed the thermally-averaged total, elastic rate coefficient for the collision of a room-temperature helium atom with an ultra-cold lithium atom. This rate coefficient has been computed as part of the characterization of a cold atom vacuum
We study the phase-space representation of dynamics of bosons in the semiclassical regime where the occupation number of the modes is large. To this end, we employ the van Vleck-Gutzwiller propagator to obtain an approximation for the Greens function of
The definitive international reference on the International System of Units (SI) is a booklet published by the International Bureau of Weights and Measures (BIPM) and often referred to as the BIPM SI Brochure. Entitled Le Systeme International d' Unites
Constantinos Makrides, Daniel Barker, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
On going efforts at the National Institute of Standards and Technology in creating a Cold Atom Vacuum Sensor device have prompted theoretical investigations of atom-molecule collisions processes that characterize its operation. Such a device will operate
R Thomas, M. Chilcott, A. Deb, Eite Tiesinga, N. Kjaergaard
Quantum mechanical scattering resonances for colliding particles occur when a continuum scattering state couples to a discrete bound state between them. The coupling also causes the bound state to interact with itself via the continuum and leads to a shift
Stephen P. Eckel, Daniel S. Barker, James A. Fedchak, Nikolai N. Klimov, Eric B. Norrgard, Julia K. Scherschligt, Constantinos Makrides, Eite Tiesinga
Cold atoms are excellent metrological tools; they currently realize SI time and, soon, SI pressure in the ultra-high (UHV) and extreme high vacuum (XHV) regimes. The development of primary, vacuum metrology based on cold atoms currently falls under the