First (n, p) measurements with the Indiana University Cyclotron Facility

1987 ◽  
Vol 65 (6) ◽  
pp. 687-690 ◽  
Author(s):  
D. Počanić ◽  
K. Wang ◽  
C. J. Martoff ◽  
S. S. Hanna ◽  
R. C. Byrd ◽  
...  
Keyword(s):  
Cross Section ◽  
Neutron Beam ◽  
Cross Sections ◽  
Distorted Wave ◽  
Indiana University ◽  
Preliminary Results ◽  
Intermediate Energies ◽  
Set Up ◽  
Wave Calculation ◽  
Good Agreement

A new monochromatic neutron-beam facility has been set up at the Indiana University Cyclotron Facility, primarily for (n, p) reaction measurements at intermediate energies (100–200 MeV). Reported are the experimental layout of the facility and preliminary results of the first measurements: 6Li(n,p)6He cross sections at six angles ranging from Θcm = 0–22°, with En = 118 MeV (laboratory). Good agreement is found between the measured σ(0°) and the cross sections measured for the mirror reaction 6Li(p, n) at 120 and 144 MeV. Results of a distorted wave calculation, while slightly lower, are consistent with the preliminary experimental 0° cross section.

scholarly journals Neutron-induced fission cross-section measurement of 234U with monoenergetic beams in the keV and MeV range using MicroMegas detectors

2019 ◽  
Vol 24 ◽  
pp. 250
Author(s):  
A. Kanellakopoulos ◽  
A. Stamatopoulos ◽  
A. Tsinganis ◽  
M. Kokkoris ◽  
R. Vlastou ◽  
...  
Keyword(s):  
Cross Section ◽  
Neutron Beam ◽  
Cross Sections ◽  
Fission Cross Section ◽  
Incident Neutron ◽  
Tandem Accelerator ◽  
Cross Section Measurement ◽  
Preliminary Results ◽  
Section Measurement ◽  
Induced Fission

The fission cross-section of 234U was measured at incident neutron energies between 300 and 500 keV and 4 and 5 MeV with a setup based on “microbulk” MicroMegas detectors. The standard 235,238U fission cross-sections were used as reference. The neutron beams were produced via the 7Li(p,n) and the 2H(d,n) reactions at the neutron beam facility of the 5.5 MeV Tandem accelerator laboratory at NCSR “Demokritos”. The mass of the actinide content of the targets used and of their impurities was quantitatively determined via α – spectroscopy. The developed methodology and preliminary results are presented.

scholarly journals Measurement of the 241Am(n,2n)240Am cross section at 17.5 MeV

2019 ◽  
Vol 21 ◽  
pp. 160
Author(s):  
A. Kalamara ◽  
R. Vlastou ◽  
M. Diakaki ◽  
M. Kokkoris ◽  
M. Anastasiou ◽  
...  
Keyword(s):  
Cross Section ◽  
Neutron Beam ◽  
Cross Sections ◽  
Reaction Cross ◽  
Activation Technique ◽  
Tandem Accelerator ◽  
Hpge Detectors ◽  
Reaction Cross Sections ◽  
Reference Reaction ◽  
High Radioactivity

The 241Am(n,2n)240Am reaction cross section has been measured at neutron beam energy 17.5 MeV, relative to the 27Al(n,α)24Na, 197Au(n,2n)196Au and 93Nb(n,2n)92mNb reference reaction cross sections, using the activation technique. The irradiation was carried out at the Van der Graaff 5.5 MV Tandem accelerator laboratory of NCSR “Demokritos” with monoenergetic neutron beam provided by means of the 3H(d,n)4He reaction, implementing a new Ti-tritiated target. The high purity Am target has been constructed at IRMM, Geel, Belgium and consisted of 40 mg 241Am in the form of AmO2 pressed into pellet with Al2O3 and encapsulated into Al container. Due to this high radioactivity (5 GBq), the Am target was enclosed in a Pb container for safety reasons. After the end of the irradiation, the activity induced by the neutron beam at the target and reference foils, was measured off-line by two 100%, a 50% and a 16% relative efficiency, HPGe detectors.

scholarly journals Coherent and incoherent channels of neutrino-nucleus reactions

2020 ◽  
Vol 16 ◽  
pp. 75
Author(s):  
P. C. Divari ◽  
T. S. Kosmas
Keyword(s):  
Cross Sections ◽  
Neutral Current ◽  
Charged Current ◽  
Preliminary Results ◽  
Scattering Cross ◽  
Neutrino Detection ◽  
Intermediate Energies ◽  
Nucleus Scattering ◽  
Scattering Cross Sections

Inelastic neutrino-nucleus scattering cross sections at low and intermediate energies are investigated for currently interesting nuclei employed in neutrino-detection experiments. This is an extension to charged current processes of our previous QRPA calculations referred to neutral current neutrino/antineutrino-nucleus reactions. Our preliminary results for the reactions 56Fe(νe, e−)56Co and 40Ar(νe, e−)40K compare rather well with similar calculations obtained in the context of continuum RPA.

Particle–Nucleus Scattering at Intermediate Energies

1972 ◽  
Vol 50 (14) ◽  
pp. 1609-1613 ◽  
Author(s):  
Melvyn E. Best
Keyword(s):  
Cross Sections ◽  
Incident Neutron ◽  
Total Neutron ◽  
Intermediate Energies ◽  
Incident Pion ◽  
Glauber Theory ◽  
Nucleus Scattering ◽  
Theory And Experiment ◽  
Good Agreement

For incident neutron energies between 20 MeV and 10 GeV the total neutron–nucleus [Formula: see text] cross sections were calculated using Glauber theory. Remarkably good agreement between experiment and theory was found at energies above 250 MeV. Using the same formalism with identical nuclear parameters, the π−–C cross sections were calculated for incident pion energies near the (3, 3) resonance. In this case, however, good agreement between theory and experiment was found for pion energies above 150 MeV.

A Variational Method for Fully Developed Laminar Heat Transfer in Ducts

1959 ◽  
Vol 81 (2) ◽  
pp. 157-164 ◽  
Author(s):  
E. M. Sparrow ◽  
R. Siegel
Keyword(s):  
Heat Transfer ◽  
Laminar Flow ◽  
Variational Method ◽  
Cross Section ◽  
Cross Sections ◽  
Axial Direction ◽  
Circular Sector ◽  
Thermal Boundary Conditions ◽  
Temperature Distributions ◽  
Good Agreement

A variational method is presented for determining fully developed velocity and temperature distributions for laminar flow in noncircular ducts. The heat addition to the fluid is taken to be uniform in the axial direction, but a variety of thermal boundary conditions are considered around the periphery of the duct cross section. Several illustrative examples are given, and comparisons are made which show good agreement with available exact solutions. These examples include ducts of rectangular and circular-sector cross sections.

Total-to-K-shell photoelectric cross-section ratios in some rare-earth and high-Z elements

1989 ◽  
Vol 67 (2-3) ◽  
pp. 139-142 ◽  
Author(s):  
S. Chandra Lingam ◽  
K. Suresh Babu ◽  
V. Prakash Kumar ◽  
D. V. Krishna Reddy
Keyword(s):  
Rare Earth ◽  
Cross Section ◽  
Atomic Number ◽  
Cross Sections ◽  
Cross Section Ratio ◽  
Section Ratio ◽  
Photoelectric Cross Section ◽  
Normal Transmission ◽  
Experimental Values ◽  
Good Agreement

The total photoelectric cross-sections in the elements gadolinium, dysprosium, erbium, lutetium, tantalum, tungsten, gold, and lead have been obtained by using the normal transmission experiments, and the results are reported. Using these total photoelectric cross sections, we have found the K-shell photoelectric cross sections, the K-jump ratios, and the total-to-K-shell photoelectric cross-section ratios at the K edges for the above elements. These values are compared with the available theoretical and experimental values. The results are in good agreement with the Storm and Israel results and the Scofield theoretical values, within the limits of experimental uncertainties. Furthermore, the variation of the total-to-K-shell photoelectric cross-section ratio with energy and atomic number is discussed.

Electron loss cross sections from rare gas atoms to Ar+

1982 ◽  
Vol 60 (7) ◽  
pp. 977-980
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Energy Region ◽  
Rare Gas ◽  
Electron Loss ◽  
Rare Gases ◽  
Thin Target ◽  
Rare Gas Atoms ◽  
Good Agreement

Measurements of the σ10 cross section for a beam of Ar+ ions of energies between 30 and 120 keV passing through a thin target of the rare gases show good agreement with the few previous measurements in this energy region.

A study of open thick microstrip: the hybrid quasistatic approximation

1989 ◽  
Vol 67 (8) ◽  
pp. 747-752
Author(s):  
M. Chryssomallis ◽  
K. Siakavara ◽  
J. N. Sahalos
Keyword(s):  
Dielectric Constant ◽  
Cross Section ◽  
Cross Sections ◽  
Effective Permittivity ◽  
Appreciable Effect ◽  
Attenuation Constant ◽  
Quasistatic Approximation ◽  
Ohmic Losses ◽  
Good Agreement

In this paper we study microstrips with rectangular and rounded edge cross sections. A hybrid quasistatic method is applied and the effective permittivity and the attenuation constant of the microstrip are found. Instead of the dielectric constant of the substrate an ideational one is used that depends on the geometry and the frequency. The attenuation constant for the rectangular microstrip was found to be in good agreement with values given in the literature. A microstrip with a rounded edge cross section has a smaller attenuation constant due to the conductor than that of a microstrip with a rectangular crosssection. Thus, a rounded edge microstrip is preferred because it will give an appreciable effect in reducing the ohmic losses of the line.

In-Plane Vibrations of Thick Circular Rings With T or I Cross Sections

1979 ◽  
Vol 46 (2) ◽  
pp. 470-472
Author(s):  
H. Lecoanet ◽  
J. Piranda
Keyword(s):  
Experimental Data ◽  
Eigenvalue Problem ◽  
Cross Section ◽  
Cross Sections ◽  
Rectangular Cross Section ◽  
Circular Rings ◽  
Theoretical Results ◽  
Good Agreement

This paper deals with the problem of eigenfrequencies and eigenvectors for rings whose cross section may be decomposed in basic rectangular cross sections. The solution is derived from a solution of the in-plane eigenvalue problem for rectangular cross-section thick rings. A good agreement between theoretical results and experimental data is obtained.

scholarly journals Near-UV photolysis cross sections of CH<sub>3</sub>OOH and HOCH<sub>2</sub>OOH determined via action spectroscopy

2007 ◽  
Vol 7 (3) ◽  
pp. 713-720 ◽  
Author(s):  
C. M. Roehl ◽  
Z. Marka ◽  
J. L. Fry ◽  
P. O. Wennberg
Keyword(s):  
Excitation Energy ◽  
Cross Section ◽  
Cross Sections ◽  
Absorption Cross ◽  
Action Spectroscopy ◽  
Near Ultraviolet ◽  
Abstract Knowledge ◽  
Methyl Hydroperoxide ◽  
Laser Apparatus ◽  
Good Agreement

Abstract. Knowledge of molecular photolysis cross sections is important for determining atmospheric lifetimes and fates of many species. A method and laser apparatus for measurement of these cross sections in the near-ultraviolet (UV) region is described. The technique is based on action spectroscopy, where the yield of a photodissociation product (in this case OH) is measured as a function of excitation energy. For compounds yielding OH, this method can be used to measure near-UV photodissociation cross section as low as 10−23 cm2 molecule−1. The method is applied to determine the photodissociation cross sections for methyl hydroperoxide (CH3OOH; MHP) and hydroxymethyl hydroperoxide (HOCH2OOH; HMHP) in the 305–365 nm wavelength range. The measured cross sections are in good agreement with previous measurements of absorption cross sections.

Sign in / Sign up

Export Citation Format

Share Document