Barry Davids
Group Member
Research Scientist - TRIUMF

Barry Davids graduated with a B.Sc. in Mathematics from the University of Chicago in 1993 and went on to complete a Ph.D. in Physics at Michigan State University. As a Ph.D. candidate, he studied the 7Be(p, γ)8B process that gives rise to most of the high-energy neutrinos emitted by the Sun. Knowledge of this process is crucial to our understanding of the solar neutrino problem. Barry performed studies to infer the astrophysical S factor of this reaction. Barry did post-doctoral work at the Kernfysisch Versneller Instituut, before coming to TRIUMF in 2003.

Barry is the project leader for EMMA (ElectroMagnetic Mass Analyser), a recoil mass spectrometer currently being developed for TRIUMF’s ISAC-II facility. When ISAC-II’s intense beams of exotic nuclei react with a target, EMMA will detect and analyze the reaction products. By studying nuclei at the edge of stability, researchers advance our knowledge of the structure of matter and of the force that holds the nucleus together. Barry is responsible for the conception, design, and funding of EMMA; commissioning of the detector is projected for 2011.

Barry also works on DSL (TRIUMF’s Doppler Shift Lifetimes facility), studying the 15O(α, γ)19Ne reaction. This reaction contributes to the ignition of x-ray bursts on accreting neutron stars. Using the Doppler shift attenuation method, Barry and his colleagues infer reaction rates of astrophysical processes like 15O(α, γ)19Ne by measuring the lifetimes of excited compound nuclei. Barry is the Chair of the TRIUMF Seminar Committee and the Nuclear Astrophysics Scientific Working Group at the Canadian Institute for Nuclear Physics. He sings bass in the Gallery Singers, an early music chamber choir.

Chris Ruiz
Group Member
Scientist - TRIUMF

Chris Ruiz is a Scientist in the Physical Sciences Division, TRIUMF, and the group leader for the DRAGON facility. He is also an Adjunct Associate Professor at the University of Victoria. 

He started out life as a 'wannabe' astronomer, studying a Bachelor's of Science degree in Astronomy and Astrophysics at the University of Edinburgh. At the end of his undergraduate degree, Chris got his first taste of experimental nuclear physics through a laboratory project studying Bell's inequality and its ramifications for quantum physics, via a really neat experiment using radioactive sodium-22. From then on he was hooked, taking a PhD with the Edinburgh Nuclear Physics Group, studying prospective indirect methods of obtaining the important 15O(a,g)19Ne stellar reaction rate at the Louvain-la-Neuve Cyclotron Research Centre in Belgium, and also the first post-accelerated radioactive beam experiment at ISAC: the resonant elastic scattering of sodium-21 on protons - requiring development of a multi-channel R-matrix code.

Chris then joined the DRAGON group as a Research Associate in 2003, eventually leading the 26Al(p,g)27Si measurement. After a short stint as a Research Associate with the University of York Nuclear Physics Group, heading the TRIUMF side of the development of the SHARC silicon barrel array, Chris was hired as a TRIUMF Board-Appointed Research Scientist in order to head the DRAGON Group in 2007. Since then, Chris has been actively involved in shaping nuclear astrophysics research at the lab along with his colleagues. In addition to the DRAGON project, Chris currently spends time working with the TUDA facility. Chris was the project leader for the ISAC Implantation Station, a facility that allows the preparation of high-quality long-lived radioactive targets for use in charged-particle induced and neutron induced reaction experiments.

Chris is a past Chair of the TRIUMF Users Group Executive Committee and former member of the Subatomic Physics Experimental Evaluation Committee. He is current Chair of the TRIUMF Undergraduate Student Scholarship Selection Committee.

Chris enjoys sailing, snowboarding, playing classical, folk and rock guitar, rock climbing, scuba diving, shooting, and attempting to cultivate an organic garden. He is also a motorcycle enthusiast. 

Falk Herwig
Group Member
University of Victoria

Falk Herwig is a professor in the Dept. of Physics of Astronomy at the University of Victoria, BC. He obtained is PhD at the Astrophysikalisches Institut Potsdam and University Kiel in Germany and held post-doctoral positions in Potsdam (Universtiy), Victoria, and Los Alamos National Laboratory, Los Alamos, NM. Before coming back to BC in 2008 he held a Lecturer faculty position at Keele University, England.

Herwig's research interests are in the simulation of the origin of the elements in stars and stellar explosions. He has worked extensively on the evolution of stars, in particular of low- and intermediate mass, white dwarfs, binary stars and their interactions, as well as the nucleosynthesis in all of these. Herwig is enthusiastic supporter of the MESA stellar evolution code and presently helps with its stewardship. He is a founding member of the NuGrid collaboration.

Another focus of his research are large-scale simulations of the hydrodynamical mixing processes in the interior of stars, that relate to the nuclear production site of the elements. In this work he combines his experience stellar research with the powerful computational tools of Paul Woodward from the University of Minnesota.

In order to analyse the nucleosynthetic signatures of various types of stars Herwig has helped to create the NuGrid collaboration (http://www.nugridstars.org) which produces codes and data sets relating to simulations of the origin of the elements. These codes allow a comprehensive analysis of the effect of individual nuclear reaction rates in a realistic simulation framework of real stars and stellar explosions. For example the inset figure shows the abundances of some key heavy elements that belong to the slow neutron capture process nucleosynthesis according to a NuGrid simulation of the interior of a 2 solar mass star.




Iris Dillmann
Group Member
Research Scientist - TRIUMF

Iris is a "lunar-tic": she always wanted to become an astronaut and be the first woman on the moon since she observed it with a telescope built by her father and watched "For all mankind" in 1989. Her dream almost came true when she joined the European Space Agency's (ESA) Astronaut Selection Programm in 2008. Unfortunately she had to stay in a lower earth orbit - but she is willing to spend her weekends hopping around on the Moon as soon as Star Trek's transporter is working properly...

She has a Master (Diplom) in chemistry from the University of Mainz/ Germany and graduated at the University of Basel/ Switzerland as "Dr. phil. nat" in astrophysics. During her PhD thesis she spent 2 years at the Research Center (KIT) in Karlsruhe/ Germany torturing the old 3.7 MV Van-de-Graaff accelerator named "Lolita" on a daily basis while measuring capture cross sections of dozens of isotopes and developing the KADoNiS database (www.kadonis.org).
After postdoc stays in Karlsruhe and the TU Munich she got a prestigeous 5-year grant from the German Helmholtz association for a Young Investigators Group ("LISA- Lifetime Spectroscopy for Astrophysics") which she led at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt/ Germany until June 2015. Since September 2013 she is working at TRIUMF and is in charge of the beta-delayed neutron program - craving for more and more neutron-rich isotopes! For this program she got awarded a NSERC Discovery Grant and a Discovery Accelerator Supplement in 2014:

Since 2015 she is Adjunct Professor at the Department of Physics and Astronomy at the University of Victoria and the Scientific Coordinator of the NSERC CREATE program IsoSiM (Isotopes for Science and Medicine, isosim.ubc.ca).

Her field of expertise is experimental nuclear astrophysics (heavy element nucleosynthesis) and nuclear physics (decay properties of exotic nuclei). Iris is the group leader of the Exotic Decay Spectroscopy Group (https://www.triumf.ca/node/39190) which investigates decay modes that occur only in very neutron-rich nuclei and in highly-charged ions with no or only a few electrons. The two experimental setups that are presently used for our research are located at RIKEN Nishina Center in Wako, Japan and at the Experimental Storage Ring at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany.During her time at GSI in Darmstadt her research group developed the particle detector CsISiPHOS for the future storage ring CR and radiation-hard diamond detectors for the Super-FRS at FAIR. Her main field of research is the investigation of half-lives and beta-delayed neutron emission probabilities of very neutron-rich isotopes with the Spanish-German neutron detector BELEN and the University of Guelph-born Canadian "poster boy" neutron detector DESCANT (as featured in Maclean's Magazine: https://twitter.com/macleansmag/status/684190168929169408 ).

When Iris is not trying to unravel the origin of the elements, she is a passionate team handball, volleyball, and soccer player and a veteran of the famous "Unified Field Heroes" which tragically lost the GSI soccer cup final 2013 after penalties. But she could prove that female scientists use their head not only for hair styling and thinking... As new resident of the we(s)t coast she tries to understand why one needs ice to play hockey (too slippery) and why no one here knows what team handball is (no, no walls!).

In her sparse free time left by travelling and science, she likes to
- relax with a good crime thriller at Kits beach,
- find out who makes the best sushi in Vancouver (Ajisai or Hitoe?),
- play (beach) volleyball and badminton. Or whatever ball or birdie she can catch/throw/hit.

Here are the links to two recent interviews she gave:

Pavel Denisenkov
Group Member
University of Victoria

Pavel Denisenkov is a senior research associate at the Department of Physics and Astronomy of the University of Victoria. He obtained his PhD degree at the Leningrad State University in 1990 and his Doctor of Science degree at the same university in 2002. He has a strong expertise in the theory of stellar evolution and numerical modeling of mixing processes coupled to nucleosynthesis in stars. 

He worked as a research associate, Humboldt Fellow and postdoctoral fellow at the Sobolev Astronomical Institute of the Saint Petersburg University (Russia), Max-Planck Institute for Astrophysics (Germany), University of Victoria (Canada), Dartmouth College (USA) and Ohio State University (USA) before coming back to the University of Victoria in 2009 to work with professors Don VandenBerg and Falk Herwig. 

Pavel was the first to include the reaction 22Ne(p,gamma)23Na in computations of H-burning phases of stellar evolution and to show that it could be responsible for Na overabundances in giant stars. He also proposed that the anomalously high Li abundances in a small fraction of red giants could be produced via the Cameron-Fowler mechanism, provided that those stars were spun up by the tidal force in a close binary system or as a result of swallowing an orbiting giant planet. 

His most recent works are related to the physics of nova stars, SNIa progenitors, and to the chemical evolution of globular clusters. In a collaboration with the TRIUMF, NuGrid and MESA teams,  Pavel has been developing and maintaining the Nova Framework that allows to simulate CO and ONe nova outbursts and post-process in detail their nucleosynthesis. With his UVic colleagues, Falk Herwig, Sam Jones and Mike Chen, Pavel has proposed a new class of hybrid white-dwarf models that consist of a small CO core surrounded by a thick ONe shell and that may lead to unusually weak SNIa explosions.

Petr Navratil
Group Member
Research Scientist (Theory) - TRIUMF

Petr Navratil graduated with a M.Sc. in Physics from the Charles University in Prague and continued with his Ph.D. studies in Nuclear Physics at the Academy of Sciences of the Czech Republic. Petr gained research experience as a postdoc at the University of Stellenbosch in South Africa and later at the University of Arizona in Tucson, where he started his work on ab initio calculation for light nuclei. Petr then spent 10 years as a staff physicist at the Lawrence Livermore National Laboratory where he continued to develop the ab initio approaches to light nuclei focusing in particular on nuclear reaction applications. Petr then join TRIUMF in October 2010 as a Research Scientist in the Theory Group.


Reactions important for astrophysics, such as 7Be(p,γ)8B, 3He(α,γ)7Be or the famous 12C(α,γ)16O are hard or impossible to measure at energies at which they occur in the stellar environment. The measurements are typically performed at higher energies and then extrapolated to the energy of interest. Predictive first-principles nuclear theory of these reactions is then essential. Even if low energy measurements are achievable in underground laboratories such as LUNA, the beam-target experiments suffer from electron screening absent in stellar environment. Again, the predictive nuclear theory becomes indispensable to extract the correct physics. The ab initio approach Petr has been developing, No-Core Shell Model/Resonating Group Method (NCSM/RGM), reached the precision to address these issues. An example of recent (and first ever ab initio) investigations within the NCSM/RGM include the 3He(d,p)4He fusion calculations relevant to the primordial nucleosynthesis and the calculations of the 7Be(p,γ)8B capture reaction important for the solar neutrino physics and the Solar Model. Ab initio calculations of the 3He(α,γ)7Be reaction are ongoing.

Reiner Kr├╝cken
Group Member
TRIUMF - Science Division

Reiner Kruecken joined TRIUMF in Feb. 2011 coming from TU Munich, Germany, where he holds the chair for Experimental Physics of Hadrons and Nuclei. Kruecken received his Ph.D. in nuclear physics from Univ. of Cologne in 1995. After being a postdoc at LBNL he moved to Yale Univ. in 1997 as Assist. Prof. at the Physics Department and WNSL until moving to Munich in 2002. His research interests are the structure of exotic nuclei and nuclear matter, nuclear astrophysics, nuclear physics applications. 2007-10 he chaired the Hadrons and Nuclei chapter of the DPG. 2003-9 he was on the German Advisory Committee for Hadrons and Nuclei (KHuK). 2006-10 he was a research area coordinator of the DFG Cluster of Excellence Origin and Structure of the Universe in Munich. He was the German science representative on the Nuclear Physics Working Group of the OECD Global Science Forum 2006-8. He is a member of various funding and advisory committees and editorial boards of Prog. Nucl. Part. Phys. and European Physical Journal A.


Reiner is the Head of TRIUMF's Science Division.