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

# Matthew Mumpower

Postdoctoral Research Fellow @ 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. My research interests are in nuclear and particle astrophysics. I currently study the interplay between nuclear physics and astrophysical environments in the rapid neutron capture or $r$-process nucleosynthesis.

Nucleosynthesis is the study of the processes by which chemical elements are synthesized in cosmic environments. Another way to say this is that I focus 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 (September 29th 2016)

### Large fragmentation observed in the $\beta$-decay intensity of $^{70}Co$

The $\beta$-decay intensity of $^{70}$Co was measured for the first time using the technique of total absorption spectroscopy. The large $\beta$-decay Q value [12.3(3) MeV] offers a rare opportunity to study $\beta$-decay properties in a broad energy range. Two surprising features were observed in the experimental results, namely, the large fragmentation of the $\beta$...

# Select Papers

#### The impact of individual nuclear properties on $r$-process nucleosynthesis

M. Mumpower, R. Surman, G. C. McLaughlin, A. Aprahamian
PPNP 86 86-126 - Published February 21st 2016
The astrophysical rapid neutron capture process or '$r$ process' of nucleosynthesis is believed to be responsible for the production of approximately half the heavy element abundances found in nature. This multifaceted problem remains one of the greatest open challenges in all of physics. Knowledge of nuclear physics properties such as masses, $\beta$-decay and neutron capture rates, as well as $\beta$-delayed neutron emission probabilities are critical inputs that go into calculations of $r$-process nucleosynthesis. While properties of nuclei near stability have been established, much still remains unknown regarding neutron-rich nuclei far from stability that may participate in the $r$ process. Sensitivity studies gauge the astrophysical response of a change in nuclear physics input(s) which allows for the isolation of the most important nuclear properties that shape the final abundances observed in nature. This review summarizes the extent of recent sensitivity studies and highlights how these studies play a key role in facilitating new insight into the $r$ process. The development of these tools promotes a focused effort for state-of-the-art measurements, motivates construction of new facilities and will ultimately move the community towards addressing the grand challenge of 'How were the elements from iron...

#### Fission Barriers at the End of the Chart of Nuclides

P. Möller, A. J. Sierk, T. Ichikawa, A. Iwamoto, M. Mumpower
Phys. Rev C 91 024310 - Published February 12th 2015
We present calculated fission-barrier heights for 5239 nuclides, for all nuclei between the proton and neutron drip lines with $171 \le A \le 330$. The barriers are calculated in the macroscopic-microscopic finite-range liquid-drop model with a 2002 set of macroscopic-model parameters. The saddle-point energies are determined from potential-energy surfaces based on more than five million different shapes, defined by five deformation parameters in the three-quadratic-surface shape parameterization: elongation, neck diameter, left-fragment spheroidal deformation, right-fragment spheroidal deformation, and nascent-fragment mass asymmetry. The energy of the ground state is determined by calculating the lowest-energy configuration in both the Nilsson perturbed-spheroid ($\epsilon$) and in the spherical-harmonic ($\beta$) parameterizations. The lower of the two results (correcting for zero-point motion) is defined as the ground-state energy. The effect of axial asymmetry on the inner barrier peak is calculated in the $\epsilon-\gamma$ parameterization. We have earlier benchmarked our calculated barrier heights to experimentally extracted barrier parameters and found average agreement to about one MeV for known data across the nuclear chart. Here we do additional benchmarks and investigate the qualitative, and when possible, quantitative agreement and/or consistency...

## 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.