What is the Origin of the Elements? 

The universe was born with just hydrogen, helium, and traces of lithium. The question of how the remaining elements were created by nuclear reactions in stars, stellar explosions, and stellar collisions is the focus of IReNA. To learn more we encourage you to visit the science pages of the various participating networks. 

JINA-CEE Science

EMMI Science (PDF)

SFB 881 SCIENCE

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IReNA Focus Areas 

IReNA is organized into eight focus areas (FA) that address critical aspects of this problem at the forefront of science. In all eight areas there is a particularly strong benefit of connecting the complementary expertise and capabilities of the various international networks and coordinate research internationally. ​

FA1: Nuclear Reaction Rates

Determination of nuclear reaction rates of critical astrophysical importance in the laboratory using a broad range of experimental approaches, including heavy ion storage rings, deep underground laboratories, intense photon beams, neutron  beams, and recoil separators at stable and rare isotope accelerator facilities,. 

Coordinators:

• Marialuisa Aliotta (Edinburgh, UK)
• Gianluca Imbriani (Naples, Italy)
• Hye Young Lee (LANL, USA)
  
• Rene Reifarth (Frankfurt, Germany)
• Michael Wiescher  (Notre Dame, USA)

FA2: Stellar Abundances

Stellar spectroscopy and the derived elemental-abundances in stars sample the composition of the Milky Way over space and time. The goal is to greatly expand these data, often referred to as the “fossil record” of chemical evolution, to form the backbone of data to which theories of element synthesis must be compared. 

Coordinators:

• Carlos Allende Prieto (Canary Islands, Spain)
• Wako Aoki (NAOJ, Japan)
• Timothy Beers (Notre Dame, USA)
• Norbert Christlieb (Heidelberg, Germany)
• Anna Frebel  (MIT, USA)

FA3: Dense Matter in Supernovae and Neutron Star Mergers

A coordinated effort to calculate the equation of state and weak interactions in extremely dense and hot nuclear matter. The results are needed in simulations of exploding stars (supernovae) and neutron star mergers to interpret multi-messenger observations. 

Coordinators:

• Kai Hebeler (TU Darmstadt, Germany)
  
• Andrew Steiner (Tennessee, USA)
  
• Ingo Tews (LANL, USA)

FA4: r-process Experiments

The rapid neutron capture process (r-process) is thought to be responsible for creating about half of all elements heavier than iron. This FA addresses the long standing challenges related to the experimental determination of the relevant nuclear reactions rates involving extremely unstable nuclei. These data are crucial for improving r-process calculations so that we can better understand observations. 

Coordinators:

• Ani Aprahamian (University of Notre Dame, USA)
• Alfredo Estrade (Central Michigan University, USA)
• Ann-Cecilie Larsen (University of Oslo, Norway)
• Shunji Nishimura (RIKEN Nishina Center, Japan)

FA5: Computer Models

Astrophysical computer models play a central role in connecting nuclear processes with observations. We address the current challenge to create models with sufficient physical fidelity for meaningful interpretation of astronomical data, pushing the boundaries of computational capabilities and requiring a multitude of explorations with different techniques and approaches. 

Coordinators:

• Carla Fröhlich (North Carolina State University, USA)
• Falk Herwig (University of Victoria, Canada)
• Frank Timmes (Arizona State University, USA)​
• Claudia Travaglio (INAF Torino, Italy)

FA6: Nuclear Data for Astrophysics

In the multi-messenger era of nuclear astrophysics an unprecedented range of nuclear data is needed to transform observations into new Windows on the Universe. The goal is to create data formats, and data infrastructure that enables the rapid exchange of nuclear data for astrophysics across disciplines and world wide research communities. 

Coordinators:

• Matt Mumpower (Los Alamos National Laboratory, USA)
• Marco Pignatari (University of Hull, UK)
• Hendrik Schatz (Michigan State University, USA)​

FA7: Weak Interactions

Reactions driven by the weak nuclear force (electron captures, beta decays, neutrino-induced reactions) play important roles in many astrophysical phenomena, such as neutron-star mergers and core-collapse supernovae. The goal is to develop new methods and techniques to better constrain weak reaction rates that are presently poorly known, or known only for stable or near stable nuclei.

Coordinators:

• Gabriel Martinez-Pinedo (TU Darmstadt, Germany)
• Toshio Suzuki (Nihon University, Japan)
• Remco Zegers (Michigan State University, USA)​

FA8:​ Professional Development and Broadening Participation 

Professional development and broadening participation are important goals, and activities designed to advance these goals are weaved into all research activity

Coordinators:

• Ana Becerril (Michigan State University, USA)
• Chikako Ishizuka (Tokyo Institute of Technology, Japan)
• Maria Lugaro (Konkoly Observatory Budapest, Hungary)
• Hendrik Schatz (Michigan State University, USA)​
• Clare Worley (University of Cambridge, UK)