$U(r)=-\frac{W_0r_0}{r}\exp\left(-\frac{r}{r_0}\right)$
$\frac{E_{bind}}{c^2}=a_1A-a_2A^{2/3}-a_3\frac{Z(Z-1)}{A^{1/3}}-a_4\frac{(N-Z)^2}{A}+\epsilon a_5A^{-3/4}$
$R=R_0\left[1+\sum_{lm}a_{lm}Y_l^m(\theta,\varphi)\right]$

# Matthew Mumpower

Staff Scientist @ Los Alamos National Lab

I'm a theoretical physicist working at Los Alamos National Lab. I received my PhD at North Carolina State University under the direction of Gail McLaughlin. At the University of Notre Dame I worked under the direction of Ani Aprahamian and Rebecca Surman. My research interests are in nuclear structure and reaction mechanisms. The study of these models has a wide range of applicability from nuclear medicine, to stockpile stewardship and even the cosmos.

At Los Alamos we seek to solve national security challenges through scientific excellence. This means we not only apply our models to the task at hand, but we seek to push them to the limits by probing the edges of our knowledge with basic science research. One way I contribute to basic science research at the lab is to study the applicability of LANL nuclear models to nucleosynthesis. Nucleosynthesis is the study of the processes by which chemical elements are synthesized in cosmic environments. In other words, this part of my research focuses on how the elements on the periodic table were created. This field is extremely challenging and also very rewarding with many real world applications. Check out the research section of this website for more information.

I firmly believe that practicing in scientific inquiry is both empowering and a necessary requirement for success in today's world. You can learn more about my teaching efforts in the teach section of this website.

Outside of Physics I enjoy keeping up with latest technology trends and coming up with unique solutions to challenging problems. For more about my entrepreneurial endeavours check out Solace Development Group. In my free time I try to stay in shape by playing racquetball. If you are interested in a game, shoot me an e-mail.

## Latest Paper (June 30th 2018)

### Californium-254 and kilonova light curves

Neutron star mergers offer unique conditions for the creation of the heavy elements and additionally provide a testbed for our understanding of this synthesis known as the $r$-process. We have performed dynamical nucleosynthesis calculations and identified a single isotope, $^{254}$Cf, which has a particularly high impact on the brightness of electromagnetic transients associated with mergers on the order...

# Select Papers

#### The impact of uncertain nuclear masses near closed shells on the $r$-process abundance pattern

M. Mumpower, R. Surman, D.-L. Fang, M. Beard, A. Aprahamian
J. Phys. G 42 034027 - Published February 5th 2015
Calculations of rapid neutron capture nucleosynthesis involve thousands of pieces of nuclear data for which no experimental information is available. Of the nuclear data sets needed for $r$-process simulations---masses, $\beta$-decay rates, $\beta$-delayed neutron emission probabilities, neutron capture rates, fission probabilities and daughter product distributions, neutrino interaction rates---masses are arguably the most important, since they are a key ingredient in the calculations of all of the other theoretical quantities. Here we investigate how uncertainties in nuclear masses translate into uncertainties in the final abundance pattern produced in $r$-process simulations. We examine the influence of individual mass variations on three types of $r$-process simulations---a hot wind, cold wind, and neutron star merger $r$ process---with markedly different $r$-process paths and resulting final abundance patterns. We find the uncertainties in the abundance patterns due to the mass variations exceed the differences due to the astrophysics. This situation can be improved, however, by even modest reductions in mass...

#### Formation of the rare earth peak: gaining insight into late-time $r$-process dynamics

M. Mumpower, G. C. McLaughlin, R. Surman
Phys. Rev. C, 85 045801 - Published April 2nd 2012
We study the formation and final structure of the rare earth peak ($A\sim160$) of the $r$-process nucleosynthesis. The rare earth peak forms at late times in the $r$-process after neutron exhaustion (neutron-to-seed ratio unity or $R=1$) as matter decays back to stability. Since rare earth peak formation does not occur during equilibrium it is sensitive to the strong interplay between late time thermodynamic evolution and nuclear physics input. Depending on the conditions the peak forms either because of the pattern of the neutron capture rates or because of the pattern of the separation energies. We analyze three nuclear data sets under different thermodynamic conditions. We find that the subtleties of each nuclear data set, including separation energies and neutron capture rates, influence not only the final shape of the peak but also when it forms. We identify the range of nuclei which are influential in rare earth peak...

## Racquetball

In my free time I play competitive racquetball. I was one of the top ranked players of the North Carolina State University Racquetball Club from 2008 to 2012. I designed their website which you can find an image of right here.