31,720 research outputs found

### The impact of atomic precision measurements in high energy physics

In this talk I discuss the relevance of atomic physics in understanding some
important questions about elementary particle physics. A particular attention
is devoted to atomic parity violation measurements which seem to suggest new
physics beyond the Standard Model. Atomic physics might also be relevant in
discovering possible violations of the CPT symmetry.Comment: Talk given at the XVII International Conference on Atomic Physics,
ICAP 2000, Florence, June 4-9, 2000. LaTeX, p.16. A sentence and a reference
have been modifie

### Weak Interactions in Atoms and Nuclei: The Standard Model and Beyond

Studies in nuclear and atomic physics have played an important role in
developing our understanding of the Standard Model of electroweak interactions.
We review the basic ingredients of the Standard Model, and discuss some key
nuclear and atomic physics experiments used in testing these ideas. We also
summarize the conceptual issues of the Standard Model that motivate the search
for new physics.Comment: 51 pages, 25 figure

### Incorporating Uncertainties in Atomic Data Into the Analysis of Solar and Stellar Observations: A Case Study in Fe XIII

Information about the physical properties of astrophysical objects cannot be
measured directly but is inferred by interpreting spectroscopic observations in
the context of atomic physics calculations. Ratios of emission lines, for
example, can be used to infer the electron density of the emitting plasma.
Similarly, the relative intensities of emission lines formed over a wide range
of temperatures yield information on the temperature structure. A critical
component of this analysis is understanding how uncertainties in the underlying
atomic physics propagates to the uncertainties in the inferred plasma
parameters. At present, however, atomic physics databases do not include
uncertainties on the atomic parameters and there is no established methodology
for using them even if they did. In this paper we develop simple models for the
uncertainties in the collision strengths and decay rates for Fe XIII and apply
them to the interpretation of density sensitive lines observed with the EUV
Imagining spectrometer (EIS) on Hinode. We incorporate these uncertainties in a
Bayesian framework. We consider both a pragmatic Bayesian method where the
atomic physics information is unaffected by the observed data, and a fully
Bayesian method where the data can be used to probe the physics. The former
generally increases the uncertainty in the inferred density by about a factor
of 5 compared with models that incorporate only statistical uncertainties. The
latter reduces the uncertainties on the inferred densities, but identifies
areas of possible systematic problems with either the atomic physics or the
observed intensities.Comment: in press at Ap

### Effective Field Theories in Nuclear Particle and Atomic Physics

These are the proceedings of the workshop on ``Effective Field Theories in
Nuclear, Particle and Atomic Physics'' held at the Physikzentrum Bad Honnef of
the Deutsche Physikalische Gesellschaft, Bad Honnef, Germany from December 13
to 17, 2005. The workshop concentrated on Effective Field Theory in many
contexts. A first part was concerned with Chiral Perturbation Theory in its
various settings and explored strongly its use in relation with lattice QCD.
The second part consisted of progress in effective field theories in systems
with one, two or more nucleons as well as atomic physics. Included are a short
contribution per talk.Comment: 56 pages, mini proceedings of the 337. WE-Heraeus-Seminar "Effective
Field Theories in Nuclear Particle and Atomic Physics," Physikzentrum Bad
Honnef, Bad Honnef, Germany, December 13 -- 17, 200

### Quantum dynamics in ultra-cold atomic physics

We review recent developments in the theory of quantum dynamics in ultra-cold
atomic physics, including exact techniques, but focusing on methods based on
phase-space mappings that are appli- cable when the complexity becomes
exponentially large. These phase-space representations include the truncated
Wigner, positive-P and general Gaussian operator representations which can
treat both bosons and fermions. These phase-space methods include both
traditional approaches using a phase-space of classical dimension, and more
recent methods that use a non-classical phase-space of increased
dimensionality. Examples used include quantum EPR entanglement of a four-mode
BEC, time-reversal tests of dephasing in single-mode traps, BEC quantum
collisions with up to 106 modes and 105 interacting particles, quantum
interferometry in a multi-mode trap with nonlinear absorp- tion, and the theory
of quantum entropy in phase-space. We also treat the approach of variational
optimization of the sampling error, giving an elementary example of a nonlinear
oscillator

### Atomic physics and modern solar spectro-polarimetry

Observational solar physics is entering a new era with the advent of new 1.5
m class telescopes with adaptive optics, as well as the Daniel K. Inouye 4 m
telescope which will become operational in 2019. Major outstanding problems in
solar physics all relate to the solar magnetic field. Spectropolarimetry offers
the best, and sometimes only, method for accurate measurements of the magnetic
field. In this paper we highlight how certain atomic transitions can help us
provide both calibration data, as well as diagnostic information on solar
magnetic fields, in the presence of residual image distortions through the
atmosphere close to, but not at the diffraction limits of large and polarizing
telescopes. Particularly useful are spectral lines of neutrals and singly
charged ions of iron and other complex atoms. As a proof-of-concept, we explore
atomic transitions that might be used to study magnetic fields without the need
for an explicit calibration sequence, offering practical solutions to the
difficult challenges of calibrating the next generation of solar
spectropolarimetric telescopes. Suggestions for additional work on atomic
theory and measurements, particularly at infrared wavelengths, are given. There
is some promise for continued symbiotic advances between solar physics and
atomic physics.Comment: Can. J. Phys., in pres

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