We would like to invite you to participate in an online IReNA sponsored workshop on all things R-matrix that will be held from June 21 - 24, 2021. This meeting will have an abbreviated format and will focus on presentations by young and early career researchers.

The aim of this meeting is to bring together a diverse group of researchers with representatives from experiment and theory who utilize the R-matrix formalism for a variety of purposes.

Talks will span a wide range of topics covering experimental, theoretical, evaluation developments using R-matrix.

Embracing the virtual nature of the workshop, the meeting will be broken into three half-day sessions. No parallel sessions are planned. Zoom will be used for the primary presentation of technical content, while substantial breaks are planned where critical informal discussion can take place in Gather.Town. Gather.Town allows us to invite you for a virtual coffee and exciting discussions.

Planned topics of discussion include:

(α,n) reactions play a pivotal role in a variety of astrophysical sites and mass regions, and they can help us understand the origin of the elements. Their astrophysical rates are the main nuclear physics uncertainty in the weak r-process (also known as the α-process), which occurs in the neutrino driven ejecta of core-collapse supernovae and can explain the production of the lighter heavy elements, that are observed in metal poor stars. The 22Ne(α,n)25Mg and 13C(α,n)16O reactions are the main neutron sources for the s- and the i-processes.

Nuclei in the Cosmos is the most important international meeting in the field of nuclear astrophysics. It brings together nuclear experimentalists, nuclear theorists, astronomers, theoretical astrophysicists, cosmo-chemists, and others interested in the scientific questions at the interface of nuclear physics and astrophysics. These questions concern, for example, the origin of the elements in the cosmos and the nuclear reactions that occur in the big bang, in stars, and in stellar explosions.

Radioactive nuclei play a significant role in many current astrophysical pursuits, from the origin of the elements to the driving of emissions from supernovae ($^5$$^6$Ni) and kilonovae (r-process radioactivity). Radioactive nuclei are crucial for direct studies of galactic enrichment ($^7$Be, $^2$$^6$Al, $^4$$^4$Ti, $^6$$^0$Fe, $^9$$^9$Tc, $^2$$^4$$^4$Pu) and stellar explosions ($^5$$^6$Ni, $^4$$^4$Ti). Stars and their explosions, galaxies and their evolving interstellar medium, and the origin of the solar system are among the targeted astrophysical objects.