New opportunities for nuclear and atomic physics on the femto- to nanometer scale with ultra-high-intensity lasers

A high-intensity, low-emittance atomic muonium (M =\mu^+ + e^-=μ++e−) beam is being developed, which would enable improving the precision of M spectroscopy measurements, and may allow a direct observation of the M gravitational interaction. Measuring the free fall of M atoms would be the first test of the weak equivalence principle using elementary antimatter (\mu^+μ+) and a purely leptonic system. Such an experiment relies on the high intensity, continuous muon beams available at the Paul Scherrer Institute (PSI, Switzerland), and a proposed novel M source. In this paper, the theoretical motivation and principles of this experiment are described.

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NEPOMUC: Neutron induced positron source Munich

Journal of large-scale research facilities JLSRF ◽

10.17815/jlsrf-1-49 ◽

2015 ◽

Vol 1 ◽

Cited By ~ 6

Author(s):

Christoph Hugenschmidt ◽

Christian Piochacz

Keyword(s):

Solid State ◽

Atomic Physics ◽

High Intensity ◽

Beam Energy ◽

Positron Beam ◽

Low Energy ◽

Surface Physics ◽

Positron Source ◽

Fundamental Research

NEPOMUC, operated by the Technische Universität München and the Universität der Bundeswehr München, provides a high-intensity low-energy positron beam for applications in solid state and surface physics as well as for fundamental research in nuclear and atomic physics. The intensity amounts to > 10<sup>9</sup> moderated positrons per second at a beam energy of E = 1 keV.

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Atomic physics with super-high intensity lasers

Reports on Progress in Physics ◽

10.1088/0034-4885/60/4/001 ◽

1997 ◽

Vol 60 (4) ◽

pp. 389-486 ◽

Cited By ~ 613

Author(s):

M Protopapas ◽

C H Keitel ◽

P L Knight

Keyword(s):

Atomic Physics ◽

High Intensity

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Cover Picture: Nanometer-Scale Modification and Welding of Silicon and Metallic Nanowires with a High-Intensity Electron Beam (Small 12/2005)

Small ◽

10.1002/smll.200590035 ◽

2005 ◽

Vol 1 (12) ◽

pp. 1133-1133

Author(s):

Shengyong Xu ◽

Mingliang Tian ◽

Jinguo Wang ◽

Jian Xu ◽

Joan M. Redwing ◽

...

Keyword(s):

Electron Beam ◽

High Intensity ◽

Nanometer Scale ◽

Metallic Nanowires

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Nanometer-Scale Modification and Welding of Silicon and Metallic Nanowires with a High-Intensity Electron Beam

Small ◽

10.1002/smll.200500240 ◽

2005 ◽

Vol 1 (12) ◽

pp. 1221-1229 ◽

Cited By ~ 129

Author(s):

Shengyong Xu ◽

Mingliang Tian ◽

Jinguo Wang ◽

Jian Xu ◽

Joan M. Redwing ◽

...

Keyword(s):

Electron Beam ◽

High Intensity ◽

Nanometer Scale ◽

Metallic Nanowires

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The Interpretation of Line Profiles

International Astronomical Union Colloquium ◽

10.1017/s0252921100053318 ◽

1977 ◽

Vol 36 ◽

pp. 191-215

Author(s):

G.B. Rybicki

Keyword(s):

Magnetic Fields ◽

Atomic Physics ◽

Velocity Fields ◽

Spectral Lines ◽

Inhomogeneous Structure ◽

The Sun ◽

Line Profiles ◽

Physical Phenomena

Observations of the shapes and intensities of spectral lines provide a bounty of information about the outer layers of the sun. In order to utilize this information, however, one is faced with a seemingly monumental task. The sun’s chromosphere and corona are extremely complex, and the underlying physical phenomena are far from being understood. Velocity fields, magnetic fields, Inhomogeneous structure, hydromagnetic phenomena – these are some of the complications that must be faced. Other uncertainties involve the atomic physics upon which all of the deductions depend.

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A New High Intensity Grid Cap for RCA-EMU-3 Electron Microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101323 ◽

1968 ◽

Vol 26 ◽

pp. 316-317

Author(s):

George Christov ◽

Bolivar J. Lloyd

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

High Voltage ◽

High Intensity ◽

Electron Gun ◽

Tungsten Filament ◽

Fluorescent Screen ◽

Electron Microscopes ◽

Pass Through ◽

Ground Potential

A new high intensity grid cap has been designed for the RCA-EMU-3 electron microscope. Various parameters of the new grid cap were investigated to determine its characteristics. The increase in illumination produced provides ease of focusing on the fluorescent screen at magnifications from 1500 to 50,000 times using an accelerating voltage of 50 KV.The EMU-3 type electron gun assembly consists of a V-shaped tungsten filament for a cathode with a thin metal threaded cathode shield and an anode with a central aperture to permit the beam to course the length of the column. The cathode shield is negatively biased at a potential of several hundred volts with respect to the filament. The electron beam is formed by electrons emitted from the tip of the filament which pass through an aperture of 0.1 inch diameter in the cap and then it is accelerated by the negative high voltage through a 0.625 inch diameter aperture in the anode which is at ground potential.

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Analyzing reactions of single mechanoenzyme molecules by light microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122538 ◽

1992 ◽

Vol 50 (1) ◽

pp. 426-427

Author(s):

Jeff Gelles

Keyword(s):

Image Processing ◽

Reaction Mechanisms ◽

Transient State ◽

Nanometer Scale ◽

Reaction Intermediates ◽

Enzyme Molecule ◽

Directed Movement ◽

Enzyme Molecules ◽

Individual Enzyme ◽

Single Reaction

Mechanoenzymes are enzymes which use a chemical reaction to power directed movement along biological polymer. Such enzymes include the cytoskeletal motors (e.g., myosins, dyneins, and kinesins) as well as nucleic acid polymerases and helicases. A single catalytic turnover of a mechanoenzyme moves the enzyme molecule along the polymer a distance on the order of 10−9 m We have developed light microscope and digital image processing methods to detect and measure nanometer-scale motions driven by single mechanoenzyme molecules. These techniques enable one to monitor the occurrence of single reaction steps and to measure the lifetimes of reaction intermediates in individual enzyme molecules. This information can be used to elucidate reaction mechanisms and determine microscopic rate constants. Such an approach circumvents difficulties encountered in the use of traditional transient-state kinetics techniques to examine mechanoenzyme reaction mechanisms.

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Microstructural characterization of sol-gel coating on PET films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172164 ◽

1994 ◽

Vol 52 ◽

pp. 886-887

Author(s):

R. T. Chen ◽

R.A. Norwood

Keyword(s):

Ion Beam ◽

Sol Gel ◽

Industrial Applications ◽

Hard Coatings ◽

Nanometer Scale ◽

Ion Beam Sputtering ◽

Process Technology ◽

Refractive Index Measurement ◽

Organically Modified ◽

Pet Films

Sol-gel processing has been used to control the structure of a material on a nanometer scale in preparing advanced ceramics and glasses. Film coating using the sol-gel process was also found to be a viable process technology in applications such as optical, porous, antireflection and hard coatings. In this study, organically modified silicate (Ormosil) coatings are applied to PET films for various industrial applications. Sol-gel materials are known to exhibit nanometer scale structures which havepreviously been characterized by small-angle X-ray scattering (SAXS), neutron scattering and light scattering. Imaging of the ultrafine sol-gel structures has also been performed using an ultrahigh resolution replica/TEM technique. The objective of this study was to evaluate the ultrafine structures inthe sol gel coatings using a direct imaging technique: atomic force microscopy (AFM). In addition, correlation of microstructures with processing parameters, coating density and other physical properties will be discussed.The materials evaluated are organically modified silicate coatings on PET film substrates. Refractive index measurement by the prism coupling method was used to assess density of the sol-gel coating.AFM imaging was performed on a Nanoscope III AFM (by Digital Instruments) using constant force mode. Solgel coating samples coated with a thin layer of Ft (by ion beam sputtering) were also examined by STM in order to confirm the structures observed in the contact type AFM. In addition, to compare the previous results, sol-gel powder samples were also prepared by ultrasonication followed by Pt/Au shadowing and examined using a JEOL 100CX TEM.

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