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This material is based upon work supported by the National Science Foundation under Grant No. PHY-1430152 (JINA Center for the Evolution of the Elements).
ArPANdo’s Week at PANArmando Castillo, Stephanie Manasterski, Victoria Zhang
Exploring the USC20 Software
Marble models helped us better understand isotopes and how particle accelerators smash nuclei.
Sometimes, we “created” new isotopes that do not exist or have not been found, and other times, the
atoms missed one another completely!
Dr. Marco Cortesi (left) introduced us to the impressive history of radiation detectors.
Such as cloud chambers, solid state detectors and others.
Afterwards, we use this knowledge to conduct our first
experiment with radioactive samples.
We learned about �⁻ decay and graphed the r and s
neutron capture processes.
Dr. Luke Roberts (right) explained his work in nuclear astrophysics,
specifically modeling the deaths of massive stars.
Our first attempt, with over 300% error! We found the half-life of the
Silver-108 to be 630.13s, which was approximately 343% off of the actual
value of 142s.
On our second attempt, we removed outliers from our data, calculating
the half-life to be 256.72s, or within 80% error of the actual value.
With the half-life of 142 seconds, it is plausible that our hypothesis is
correct.
Monday
Tuesday
Wednesday
Thursday
Dr. Stephanie Lyons (right) spoke on nuclear experimentation. Afterwards, we calculated the atomic masses and binding energies of isotopes, such as
Oxygen-15.
We conducted an experiment to understand the elemental composition of a strange rock. This rock had two
isotopes of silver and only two isotopes of cadmium. Thus, it lacked several
naturally occurring isotopes of cadmium. This discrepancy led us to
hypothesize that the rock was originally composed completely of silver, that it was irradiated, and that the irradiated silver beta-decayed over time into the
cesium isotopes. To test this hypothesis, we determined the half-life of the isotope Silver-108. This would
allow us to estimate the rock’s chemical makeup, which we would compare to its
actual composition.
Dr. Brian O’Shea (right) taught us about galaxies, telescopes, and the makeup of the Milky
Way. He showed us simulations of entire galaxies that were
generated with supercomputers.
Our lego model representing the energy levels and decay modes of
the first ten nuclide isotopes.
Dr. Alex Brown gave us a tool to theoretically predict nuclear energy and densities. These are such generated diagrams of Calcium-60, a stable (non-radioactive) isotope. Calcium-60 has 20 protons and 40 neutrons,
which are “magic numbers.” Thus, the isotope is stable.
The diagrams tell us the isotope’s quantum numbers and parity as well as the dispersion of protons and neutrons in the nucleus.
Our goal was to determine an unknown substance by analyzing its gamma ray emission decay scheme. We would be able to determine the substance by matching its peak(s) in energy to
data from the LBNL Radiation Database.
We used USC20 software to collect data, which we calibrated using the decay schemes for Cobalt-60 and Cesium-137.
Our data gave a peak of 808 KeV +/- 19.05 KeV, as illustrated in the graph. By searching in the database, we determined that the
substance was Manganese-54.
