Compton Scattering of Laser photons (LCS) off circulating electrons in a storage ring produce photon beams of high energies and high degree of polarization. First proposed in early 1960s, the LCS are proving to be powerful sources thanks to the development of 3rd Generation rings and high power laser systems. They can provide intense gamma ray beams to be useful in basic science and industrial research of importance to nuclear medicine, non-destructive testing and nuclear waste management. This facility will be of interest to material testing and nuclear science and energy related research.

I will present the principles of such systems, our plans to build one at the Canadian Light Source located on our university campus. The audience will appreciate its capacity and potential uses. This is also an open invitation to join collaboration in developing the facility and its subsequent use.

Under the assumption of charge symmetry of the nuclear force, nuclei form mirror pairs that have similar spectral properties. This mirror symmetry, in which the mirror pair is obtained by exchanging protons with neutrons, has been useful in obtaining information on nuclei not well studied experimentally. In 2006, we predicted narrow resonances in the nucleus 15F, which is beyond the proton drip line. These predictions were verified by new experimental results published in 2009. Work is now in progress on other such mirror systems. In particular, the structure of 17C has been used to define a nuclear interaction which, when used in a multichannel algebraic scattering theory for the n+16C system, gives a credible definition of the excitation spectra of the compound nucleus. That interaction is then used for the mirror system p+16Ne, on adding a Coulomb field, to specify the low excitation spectrum of the particle-unstable 17Na. We estimate the, as yet unknown, ground state of 17Na by surveying the set of known threshold excitations of mirror systems. The same procedure is being considered for other mirror systems, such as using n+18O to obtain information on the nucleon-core interaction that would be used to study 19Na as a p+18Ne compound system.

Type Ia supernovae are known as the precise distance indicators that allowed the remarkable discovery of the accelerated expansion of the universe. Despite this astounding feat, there still remain large uncertainties in many of the key issues surrounding these extremely energetic events. These uncertainties, while not being horribly detrimental to their use as distance indicators, hamper the understanding of the far reaching consequences these cosmic factories of heavy elements have on the chemical evolution of the Universe.

Type Ia Supernovae can be divided into three distinct phases. The pre-supernova evolution, the explosion itself and the expansion phase, which results in spectra and light-curves.

In this talk I will first present our findings on the progenitor question (pre-supernova phase): Are these objects the result of the merger of two white dwarves or one white dwarf accreting from a non-degenerate companion. In the second case, the companion will most likely survive the event and should be seen, post-explosion, in remnants. We have scrutinized two ancient remnants for such a companion star, namely those of SN1572 and SN1006. I will show the findings in the context of other research in that area.

In a second part of the the talk, I will outline how to extract information like energies and yields from optical spectra of Type Ia Supernovae fitting them with synthetic spectra. In particular, my work pertains to the automation of this complex fitting processes. I will discuss the merits of the automated fitting many Type Ia supernovae and will outline our progress using artificial intelligence algorithms.

Cosmic strings are topological defects which are predicted to arise in many fundamental theories of microphysics. If stable, they will form in the very early universe and persist to the present time. Searching for the gravitational effects of strings in observational cosmology is therefore a way to constrain particle physics beyond the "Standard Model". I will present new ways of searching for cosmic strings in cosmic microwave temperature and polarization maps as well as in 21cm redshift surveys.

X-ray observations of active galactic nuclei (AGNs) reveal the physics at work in the region closest to the black hole event horizon . I will discuss some recent X-ray observations of AGNs and describe the processes responsible for the complex spectral appearance and the extreme variability in the light curves. I will discuss what this tells us about the black hole environment and even about the black hole itself. I will discuss the future of black hole studies, in particular focussing on the tremendous advances that the Astro-H X-ray observatory will provide for us in this field.

How were all the elements in the universe created? Scientists across many disciplines have been trying to answer this question for decades. Much progress in our understanding of nucleosynthesis has been made, but the origin of half the elements heavier than iron is still unknown. Supernovae are possible sources of heavy-element production, whereby elements are produced through a rapid series of nuclear reactions on neutron-rich nuclei in a process termed the astrophysical ‘r’ process. In an attempt to reproduce the observed distribution of element abundances in the universe, models are generated which inherently rely upon many nuclear physics inputs, including the masses of the nuclides involved and their beta-decay properties. However, the uncertainties in these nuclide properties are often too large and limit our understanding of heavy-element nucleosynthesis.

Ion traps have revolutionized mass spectroscopy and have the potential to do the same for beta-decay spectroscopy as well. Precise mass measurements of radioactive nuclides are now routinely performed around the world, but nuclides involved in the astrophysical ‘r’ process are often too challenging to produce for study at accelerator facilities. The newly commissioned CARIBU facility, an upgrade to Argonne National Laboratory's ATLAS facility, provides copious amounts of these previously elusive neutron-rich nuclei. A program of mass measurements at CARIBU is underway, where the Canadian Penning trap mass spectrometer will be used to determine the masses of more than 150 nuclides. In addition, a specially designed ion trap is currently being developed to facilitate a new program of beta-decay spectroscopy using nuclides produced by CARIBU. Results from a feasibility study conducted within the past year have indicated this new technique of using ion traps to perform beta-decay studies could significantly advance the field. Indeed, ion traps for astrophysics are going where no trap has gone before.

The Standard Model of Particles and Interactions describes our current understanding of the fundamental particles that make up matter and their interactions. However, there are still many unanswered questions, such as the origin of dark matter and dark energy, which together make up 95% of the energy in the universe, but are not yet included in the Standard Model. Various extensions to the Standard Model predict the existence of new particles, some of which could be dark matter candidates. The Standard Model can be tested with direct searches for as-yet-undiscovered particles, such as the Higgs boson, at colliders which explore the energy frontier such as the Large Hadron Collider. An alternative, yet complementary, approach is to search for physics beyond the Standard Model by making extremely precise measurements of Standard Model quantities, where deviations from predicted values would indicate the presence of new physics. Qweak and MOLLER comprise a program of measurements at Jefferson Lab which will test the Standard Model by exploiting the property of parity-violation in the weak interaction. They will measure the parity-violating asymmetry in elastic electron-proton or electron-electron (Møller) scattering, respectively, anticipated as the world’s most precise measurements of the weak mixing angle, sin2θW, away from the Z resonance. I will describe the experiments and their potential impact on the development of the New Standard Model.

One of the major successes in the description of the properties of atomic nuclei was the introduction of the nuclear shell model. The magic numbers associated with closed shells have long been assumed to be valid over the whole nuclear chart. In the last decades it was found that the well-known magic numbers for atomic nuclei can change locally when going from the valley of stability to nuclei with extreme N/Z ratios, leading to the disappearance of classic shell gaps and the appearance of new magic numbers. This evolution of the magic numbers is one of the major topics in both experimental and theoretical nuclear structure research. Changes in nuclear structure have a vast impact on the binding energies of nuclei, their decay properties, as well as on their excitation-energy spectra. Understanding the underlying phenomena causing these changes is of great importance to be able to reliably extrapolate nuclear structure properties towards the drip-lines. Direct reactions are a very successful method to study the structure of nuclei. Nucleon transfer and knockout reactions are used to extract the most detailed information on the position and occupation of energy levels, and thus to study the evolution of shell structure in exotic nuclei. In this talk I will present recent results from transfer and knockout reaction experiments performed at ISOLDE/CERN and NSCL.

Atomic nuclei are the core of matter and the fuel of stars. The dynamics of this many-body system made of protons and neutrons are governed by the strong force. Short lived nuclei, so-called rare isotopes or exotic nuclei, hold the key to our understanding of the workings of the strong force in nuclei and nuclear matter as well as of the origin of the heavy chemical elements that are created in explosions of massive stars. TRIUMF, Canada's national laboratory for nuclear and particle physics, operates one of the world's leading facilities for rare isotope beams, ISAC, and is currently constructing the new Advanced Rare IsotopE Laboratory (ARIEL). In this talk I will present how experiments with rare isotopes at TRIUMF are recreating in the laboratory the nuclear reactions inside supernova explosions and how these studies can reveal important aspects of workings of the strong force in nuclei and neutron stars.

BIOGRAPHICAL NOTES

Reiner Kruecken is Head of the Science Division at TRIUMF, Canada’s National Laboratory for Particle and Nuclear Physics. He joined TRIUMF in February 2011 after 8 1/2 years at the Technical University Munich, Germany, where he holds the chair (C4) for Experimental Physics of Hadrons and Nuclei. Kruecken received his Ph.D. in nuclear physics from the University of Cologne in 1995. After a postdoctoral fellowship at Lawrence Berkeley National Laboratory he moved to Yale University in 1997 where he was an Assistant Professor at the Physics Department and the A.W. Wright Nuclear Structure Laboratory until he moved to Munich in 2002. His current research interests are in the area of the structure of exotic nuclei and nuclear matter, nuclear astrophysics, as well as applications of nuclear physics methods to radiation biology and medicine.

The stratosphere is a region of the atmosphere that has been famously known for decades for the depletion of the ozone layer. However, it has recently been recognized that the stratosphere is coupled in important ways to the temperature of the Earth's surface, for understanding both short term weather and long term climate. One of the key parameters of stratospheric composition is aerosol, which, by scattering incoming solar radiation, has an overall global cooling impact. Over time, this has a large natural variability due to the impact of energetic volcanic eruptions that can inject aerosol directly to the stratosphere. The Canadian OSIRIS satellite instrument is one of the few operational satellites that can measure aerosol in the stratosphere through a remote sensing technique known as limb scattering. This talk will review the physics involved in making these measurements and highlight several results from the study of recent volcanic eruptions.

The study of the atomic nucleus, a field that started over a century ago, still continues to fascinate. A wide variety of different theoretical approaches currently aim at tackling this many-body problem. Improved experimental data are crucial for testing modern theoretical approaches at the extreme limit of nuclear existence, where they are the most sensitive. One of the most extreme systems observed in nature is the occurrence of a neutron halo structure in very exotic nuclei. In these neutron-rich systems, some of the neutrons are extremely weakly bound resulting in their wavefunction extending far outside the nuclear core forming a so-called halo. These nuclei are described by two observables: their charge radius and the neutron separation energy of their valence neutrons. The first quantity describes the motion, size and deformation of the core, while the extent of the diffuse region, is linked to the second quantity. Recent advances in laser spectroscopy and high-precision atomic physics calculations have led to charge radii determinations precision that requires accurate mass measurements with precisions of δm/m ~ 10-7. However, being very short-lived and produced at low yields, direct mass measurements of neutron halo nuclei at this level of precision could not be achieved until recently. Using the uniquely high yields available at the ISAC facility, the TRIUMF Ion Trap for Nuclear and Atomic science (TITAN) Penning trap performed mass measurements of the halo nuclei 6,8He, 11Li and 11Be. The resulting improved mass values led to more precise and accurate determination of the associated charge radii. Using the charge radii and the binding energies of halo nuclei, we show that one can test the limitations of various ab-initio nuclear theories, which leads to a better comprehension of the interactions at play in the nucleus.

Phononic crystals - periodic composite materials with lattice spacings comparable to the wavelength of acoustic or elastic waves – may be considered ideal systems for investigating a variety of unusual wave phenomena. One of these is focusing of waves by negative refraction. Since this phenomenon was first demonstrated several years ago by our group, there has been increasing interest in the possibility that focusing with resolution better than the diffraction limit may be achievable. In this talk, I will discuss how super-resolution can be realized with two-dimensional phononic crystals that are made of stainless steel rods assembled in a triangular crystal lattice and immersed in a liquid. Our experimental results are compared with theoretical predictions by the Finite Difference Time Domain (FDTD) method, thereby elucidating the mechanism that enables super resolution to be observed. I will examine the factors influencing the resolution limit of our flat phononic crystal lens, and comment on how this work may serve as a guide for the design of new phononic crystal lenses with improved resolution capabilities.

The traditional notion of a "particle" in Minkowski space quantum field theory is tied mathematically to Poincare invariance and physically to families of inertial observers. The notion does however not have a straightforward generalisation to curved spacetimes or to non-inertial observers: a celebrated consequence is Hawking's prediction of black hole radiation. This talk discusses point like model particle detectors as a tool for probing a quantum field in situations where the spacetime, the quantum state or the detector's motion has nontrivial kinematics. We shall in particular address how nonstationarity in the detector's trajectory or in the quantum state can be isolated from transient switch-on and switch-off effects. Applications include a particle detector falling into a (2+1)-dimensional black hole.

It is well known that the micromation of inductors is a bottleneck problem for the integration of electronic systems. Developing magnetic materials with high permeability in GHz can be one effective way to solve the problem. However, Snoek’s limit shows that it is difficult to search for such materials. In this talk we develop a model which indicates the high permeability in GHz can be achieved in magnetic nanomaterials. Then, the adjusting methods of the high frequency characteristics for the magnetic nanomaterials are described and realized experimentally. The measurement technology of the high frequency characteristics will also be discussed.