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

# 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 (February 23rd 2017)

### Neutron-capture rates for explosive nucleosynthesis: the case of $^{68}$Ni$(n,\gamma)^{69}$Ni

Neutron-capture reactions play an important role in heavy element nucleosynthesis, since they are the driving force for the two processes that create the vast majority of the heavy elements. When a neutron capture occurs on a short-lived nucleus, it is extremely challenging to study the reaction directly and therefore the use of indirect techniques is essential. The present...

# 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...

#### Sensitivity studies for a main $r$ process: nuclear masses

A. Aprahamian, I. Bentley, M. Mumpower, R. Surman
AIP Advances 4, 041101 - Published February 16th 2014
The site of the rapid neutron capture process ($r$ process) is one of the open challenges in all of physics today. The $r$ process is thought to be responsible for the creation of more than half of all elements beyond iron. The scientific challenges to understanding the origin of the heavy elements beyond iron lie in both the uncertainties associated with astrophysical conditions that are needed to allow an $r$ process to occur and a vast lack of knowledge about the properties of nuclei far from stability. One way is to disentangle the nuclear and astrophysical components of the question. On the nuclear physics side, there is great global competition to access and measure the most exotic nuclei that existing facilities can reach, while simultaneously building new, more powerful accelerators to make even more exotic nuclei. On the astrophysics side, various astrophysical scenarios for the production of the heaviest elements have been proposed but open questions remain. This paper reports on a sensitivity study of the $r$ process to determine the most crucial nuclear masses to measure using an $r$-process simulation code, several mass models (FRDM, Duflo-Zuker, and HFB-21), and three potential astrophysical...

## 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.