A5033785965- Nuclear physics research studies
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Advanced Chemical Physics Studies
- Radiation Detection and Scintillator Technologies
- Radiation Therapy and Dosimetry
- Neutrino Physics Research
- Particle Detector Development and Performance
- Medical Imaging Techniques and Applications
- Photocathodes and Microchannel Plates
- Radioactive Decay and Measurement Techniques
- Optical Coherence Tomography Applications
- Scientific Research and Discoveries
- Quantum, superfluid, helium dynamics
- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Radiation Dose and Imaging
- Vibration and Dynamic Analysis
- Atmospheric Ozone and Climate
- Molecular Spectroscopy and Structure
- Particle accelerators and beam dynamics
- Control Systems in Engineering
Vanderbilt-Ingram Cancer Center
2016
Vanderbilt University
2016
Texas A&M University
2006-2014
The University of Texas Health Science Center at San Antonio
2009
Queen's University
2006
We present the first study of \ensuremath{\beta} decay $^{23}\mathrm{Al}$ undertaken with pure samples. The was motivated by nuclear astrophysics questions. Pure samples were obtained from momentum achromat recoil separator (MARS) Texas A University, collected on a fast tape-transport system, and moved to shielded location where \ensuremath{\beta}-\ensuremath{\gamma} coincidence measurements made. deduced branching ratios log $\mathit{ft}$ values for transitions states in $^{23}\mathrm{Mg}$,...
A precision measurement of the gamma yields following beta decay 32Cl has determined its isobaric analogue branch to be (22.47^{+0.21}_{-0.19})%. Since it is an almost pure Fermi decay, we can also determine amount isospin-symmetry breaking in this superallowed transition. We find a very large value, delta_C=5.3(9)%, agreement with shell-model calculation. This result sets benchmark for isospin-symmetry-breaking calculations and lends support similarly-calculated, yet smaller, corrections...
We measured ${}^{14}\mathrm{O}+{}^{4}\mathrm{He}$ excitation functions for elastic scattering which demonstrate, the first time, a well developed $\ensuremath{\alpha}$-cluster structure in proton rich nucleus, ${}^{18}\mathrm{Ne}$. present energies and estimates of spins dominant resonances using an R-matrix approach. A resonance at 9.2 MeV energy ${}^{18}\mathrm{Ne}$ is particularly interesting. The spin-parity state found to be ${3}^{\ensuremath{-}}$ $\ensuremath{\alpha}$ particle reduced...
The cross section of the radiative proton capture reaction on drip line nucleus $^{12}\mathrm{N}$ was investigated using asymptotic normalization coefficient (ANC) method. We have used $^{14}\mathrm{N}(^{12}\mathrm{N},^{13}\mathrm{O})^{13}\mathrm{C}$ transfer at 12 MeV/nucleon to extract ANC for $^{13}\mathrm{O}\ensuremath{\rightarrow}^{12}\mathrm{N}+p$ and calculate from it direct component astrophysical $S$ factor $^{12}\mathrm{N}(p,\ensuremath{\gamma})^{13}\mathrm{O}$ reaction. optical...
A preliminary indirect investigation of the 18O(p, α)15N reaction via THM is discussed, focusing on extraction resonance parameters 656 keV (corresponding to state at Ex = 8.65 MeV in 19F), which gives strong contribution both low and high temperatures, being quite broad. Even though a non-negligible discrepancy found, as regards strength energy resonance, no change rate apparent astrophysically relevant temperature range.
Background: Models to calculate small isospin-symmetry-breaking effects in superallowed Fermi decays have been placed under scrutiny recent years. A stringent test of these models is measure transitions for which the correction predicted be large. The decay 32Cl provides such a case. Purpose: To improve gamma yields following beta and determine ft values branches, particularly one isobaric-analogue state 32S. Method: Reaction-produced recoil-spectrometer-separated collected tape transported...
The asymptotic normalization coefficients of the bound states ${J}^{\ensuremath{\pi}}=({0}_{1}^{+},{2}_{1}^{+},{4}_{1}^{+},{2}_{2}^{+})$ in $^{18}\text{O}$ are extracted from peripheral neutron transfer reaction $^{13}\text{C}$$(^{17}\text{O}$$,^{18}\text{O}$$)^{12}\text{C}$. They then converted to their mirror $^{18}\text{Ne}$, which further used evaluate astrophysical $S$ factor for proton capture $^{17}\text{F}$($p$,$\ensuremath{\gamma}$)$^{18}\text{Ne}$. elastic-scattering cross sections...
We observed single and double proton emissions in the $^{14}\mathrm{O}+^{4}\mathrm{He}$ interaction by thick target inverse kinematic (TTIK) method at initial energy for $^{14}\mathrm{O}$ 32.7 MeV. found that protons mainly originate from resonance excitation of states $^{18}\mathrm{Ne}$. The $^{18}\mathrm{Ne}$ decay to unstable $^{17}\mathrm{F}$. It was a state ${E}_{\mathrm{ex}}=8.45$ MeV demonstrates features correlated pair. properties make previous interpretation rate...
We have measured the beta-decay branching ratio for transition from $^{21}\mathrm{Na}$ to first excited state of $^{21}\mathrm{Ne}$. A recently published test standard model, which was based on a measurement $\ensuremath{\beta}\text{\ensuremath{-}}\ensuremath{\nu}$ correlation in decay $^{21}\mathrm{Na}$, depended this ratio. However, until now only relatively imprecise (and, some cases, contradictory) values existed it. Our new result, $4.74(4)%$, reduces but does not remove reported...
Abstract Precise absolute distance measurements are crucial in both scientific and industrial fields. Among various techniques, dual-comb ranging stands out due to its high precision fast acquisition rate. However, the inherent periodicity of comb pulse train leads limited non-ambiguity range (NAR) periodic measurement dead zones, thereby impeding practical applications. Here, we propose demonstrate an arbitrary system utilizing dual repetition rate parallel linear asynchronous optical...
Purpose: Developing a method of an HPGe detector precise γ efficiency calibration which is very important for accurate radiation detection during cancer radiotherapy practices. Method and Materials: radioactive nucleus produced separated with Momentum Achromat Recoil Spectrometer (MARS) at the K500 superconducting cyclotron Texas A&M University has positron decays followed by transitions up to 8 MeV from excited states, used β-γ coincidence measurement 1-mm-thick BC404 plastic scintillator,...
Purpose: To obtain an improved precise gamma efficiency calibration curve of HPGe (High Purity Germanium) detector with a new comprehensive approach. Methods: Both radioactive sources and Monte Carlo simulation (CYLTRAN) are used to determine for energy range 0–8 MeV. The is GMX coaxial 280 cm3 N-type 70% detector. Using Momentum Achromat Recoil Spectrometer (MARS) at the K500 superconducting cyclotron Texas A&M University, nucleus 24 Al was produced separated. This has positron decays...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation R. E. Tribble, T. Al‐Abdullah, A. Alharbi, J. Äystö, Banu, V. Burjan, F. Carstoiu, X. Chen, H. L. Clark, Davidson, C. Fu, Gagliardi, Hardy, Iacob, Jokinen, Kroha, Y.‐W. Lui, M. McCleskey, Mukhamedzhanov, N. Nica, I. Park, B. Roeder, Saastamoinen, Simmons, G. Tabacaru, Y. Tokimoto, Trache, P. Woods, Zhai;...
Purpose: A Monte Carlo study for characterization of solid brass compensators used IMRT is performed, to investigate their dosimetric properties. Method and Materials: group various with different shapes were constructed simulated by code EGSnrc (BEAMnrc/DOSXYZnrc). Varian 2100Ex linear accelerator was commissioned prior the simulation compensators. The included five slab thicknesses ranging from 1 7cm varying thickness within field. same fluences as ones produced created using Millennium...
The THM has been applied to the study of reactions involved in fluorine production AGB stars with aim extending these measurements down Gamow peak. Fluorine abundance is important since it allows constrain mixing models from comparison observed abundances ones predicted by models. In particular focuses on 15N(p,α)12C and 18O(p,α)15N which can influence yield as they are part 19F (and destruction) network.
The Trojan Horse Method (THM) is an unique indirect technique allowing to measure astrophysical rearrangement reactions down relevant energies. basic principle and a review of the recent applications are presented. aiming extraction bare Sb(E) for some two‐body processes discussed.
It was expected that γ rays from 18F and 22Na would be observed in massive One novae, but neither has been to date. The 17F(p,γ)18Ne 22Mg(p,γ)23Al reactions may play important roles the production destruction of 22Na. We have determined asymptotic normalization coefficients for 18Ne 23Al through measurements peripheral neutron transfer mirror nuclear systems. use ANCs calculate astrophysical S‐factors reaction rates these two reactions.
The Trojan Horse Method has been recently applied to the study of reactions involved in fluorine nucleosynthesis inside AGB stars. Fluorine abundance is important since it allows constrain mixing models from comparison observed abundances with ones predicted by models. Anyway direct measurements cross section do not extend down Gamow peak, which astrophysically relevant energy region. In particular focuses on 15N(p,α)12C and 18O(p,α)15N can influence yield as they are part 19F...