Nuclear Physics
Beta-Decay & Gamma Spectroscopy
I am studying nuclear spectroscopy of neutron-rich nuclides in the mid-range of the Chart of Nuclides under Dr. Jeffry Winger (Miss. State Univ).
Analysis of the decay chain Cu74 - Zn74 - Ga74 - Ge74 from the decay of a Uranium parent nuclide, performed with a four-clover set of high-purity germanium gamma detectors, is being completed. This data was collected using a moving tape collector and beta-gated during data acquisition. As part of this analysis, which expands on previous analyses of this decay chain by identification of multiple new lines and energy levels, we are doing statistical verifications of the intensities to further define multiply-placed lines that overlap.
A problem in post-fission decay is the profile of radiation from the radioactive daughters and granddaughters of the fission nuclides. This is called pandemonium; there are several nuclides which contribute heavily to this issue. While 74Cu is not one of those primary contributors, its large Q-beta window and structural similarity to those contributors makes 74Cu a tantalizing example to study high-lying states that are currently unknown in these decays.
Presentations on progress on this work have been performed at the 2014 Mississippi Academy of Sciences conference and at the Exotic Beam Summer School (EBSS) 2014. A paper is near completion for submission for peer review.
Analysis of the decay chain Cu74 - Zn74 - Ga74 - Ge74 from the decay of a Uranium parent nuclide, performed with a four-clover set of high-purity germanium gamma detectors, is being completed. This data was collected using a moving tape collector and beta-gated during data acquisition. As part of this analysis, which expands on previous analyses of this decay chain by identification of multiple new lines and energy levels, we are doing statistical verifications of the intensities to further define multiply-placed lines that overlap.
A problem in post-fission decay is the profile of radiation from the radioactive daughters and granddaughters of the fission nuclides. This is called pandemonium; there are several nuclides which contribute heavily to this issue. While 74Cu is not one of those primary contributors, its large Q-beta window and structural similarity to those contributors makes 74Cu a tantalizing example to study high-lying states that are currently unknown in these decays.
Presentations on progress on this work have been performed at the 2014 Mississippi Academy of Sciences conference and at the Exotic Beam Summer School (EBSS) 2014. A paper is near completion for submission for peer review.
Binding Energy & Ground State Nuclear Structure
rms variance from AME2012: 450 keV!
Nucleosynthesis models require good accuracies of nuclear mass predictive models, particularly in the so-called "terra incognita" region of the Chart of Nuclides. I am pursuing an separate investigation of the Atomic Mass Evaluation 2012 (AME2012) to develop a new systematic method to predict masses of nuclei in a new model called "ADN" (alpha-deuteron-neutron). This model assumes a simple quadratic fit of isotopic trends of binding energies, and then identifies subsequent trends in each fit coefficient as a function of core size.
By deconstructing these trends and subtrends, it is expected that the global trends can lead to descriptions of microscopic qualities. Additionally, by fitting directly the binding energies as opposed to the mass surfaces, the ability to extend with good confidence the predictive power of the ADN model beyond the known Chart of Nuclides. Currently, the root-mean-square variance of the ADN for Even Z is 450 keV, well on the way to the 100-keV goal and quite competitive with the results for leading mass prediction models.
The image at the top of this page is the set of linear coefficients from all quadratic fit functions for nuclei with a common N=Z core size. You can read more about this by clicking on this link to my ResearchGate profile, where the latest version of this paper can be downloaded. An experiment has been submitted requesting investigation of certain N=Z mass data for comparison among the current models, including the ADN, at the National Superconducting Cyclotron Laboratory (NSCL).
Nucleosynthesis models require good accuracies of nuclear mass predictive models, particularly in the so-called "terra incognita" region of the Chart of Nuclides. I am pursuing an separate investigation of the Atomic Mass Evaluation 2012 (AME2012) to develop a new systematic method to predict masses of nuclei in a new model called "ADN" (alpha-deuteron-neutron). This model assumes a simple quadratic fit of isotopic trends of binding energies, and then identifies subsequent trends in each fit coefficient as a function of core size.
By deconstructing these trends and subtrends, it is expected that the global trends can lead to descriptions of microscopic qualities. Additionally, by fitting directly the binding energies as opposed to the mass surfaces, the ability to extend with good confidence the predictive power of the ADN model beyond the known Chart of Nuclides. Currently, the root-mean-square variance of the ADN for Even Z is 450 keV, well on the way to the 100-keV goal and quite competitive with the results for leading mass prediction models.
The image at the top of this page is the set of linear coefficients from all quadratic fit functions for nuclei with a common N=Z core size. You can read more about this by clicking on this link to my ResearchGate profile, where the latest version of this paper can be downloaded. An experiment has been submitted requesting investigation of certain N=Z mass data for comparison among the current models, including the ADN, at the National Superconducting Cyclotron Laboratory (NSCL).