572 research outputs found
Nonrelativistic ionization energy for the helium ground state
The helium ground state nonrelativistic energy with 24 significant digits is
presented. The calculations are based on variational expansion with randomly
chosen exponents. This data can be used as a benchmark for other approaches for
many electron and/or three-body systems.Comment: 3 pages, 0 figure
Ionization Potential of the Helium Atom
Ground state ionization potential of the He^4 atom is evaluated to be 5 945
204 221 (42) MHz. Along with lower order contributions, this result includes
all effects of the relative orders alpha^4, alpha^3*m_e/m_alpha and
alpha^5*ln^2(alpha).Comment: 4 page
Search for long-lived states in antiprotonic lithium
The spectrum of the (L_i^3 + p-bar + 2e) four-body system was calculated in
an adiabatic approach. The two-electron energies were approximated by a sum of
two single-electron effective charge two-center energies as suggested in [6].
While the structure of the spectrum does not exclude the existence of
long-lived states, their experimental observability is still to be clarified
Corrections to the Nonrelativistic Ground Energy of a Helium Atom
Considering the nuclear motion, the authors give out the nonrelativistic
ground energy of a helium atom by using a simple but effective variational wave
function with a flexible parameter . Based on this result, the relativistic
and radiative corrections to the nonrelativistic Hamiltonian are discussed. The
high precision value of the helium ground energy is evaluated to be -2.90338
a.u., and the relative error is 0.00034%.Comment: 8 pages, no figures, 2 table
High accuracy results for the energy levels of the molecular ions H2+, D2+ and HD+, up to J=2
We present a nonrelativistic calculation of the rotation-vibration levels of
the molecular ions H2+, D2+ and HD+, relying on the diagonalization of the
exact three-body Hamiltonian. The J=2 levels are obtained with a very high
accuracy of 10^{-14} a.u. (for most levels) representing an improvement by five
orders of magnitude over previous calculations. The accuracy is also improved
for the J=1 levels of H2+ and D2+ with respect to earlier works. Moreover, we
have computed the sensitivities of the energy levels with respect to the mass
ratios, allowing these levels to be used for metrological purposes.Comment: 11 page
Constrains on non-Newtonian gravity from the experiment on neutron quantum states in the Earth's gravitational field
An upper limit to non-Newtonian attracive forces is obtained from the
measurement of quantum states of neutrons in the Earth's gravitational field.
This limit improves the existing constrains in the nanometer range
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