California's Most Vulnerable Parents: When Maltreated Children Have Children

This report takes an in-depth look at the intersection between teen births, child maltreatment, and involvement with the child protection system. Putnam-Hornstein, along with other researchers at USC and the University of California, Berkeley, linked and then analyzed roughly 1.5 million California birth records and 1 million CPS records, with a second phase of research focusing on the maltreatment risk of children born to adolescent mothers.In 2012, California became one of the first states in the nation to extend foster youth status until age 21. Different programs and services will likely be required to adequately respond to the needs and circumstances of non-minor youth who remain in the foster care system, particularly in the area of parenting supports. This report finds that as many as one in three female youth in California may be parenting by the time they exit the foster care system on their 21st birthday

Radiation Generated by Charge Migration Following Ionization

Electronic many-body effects alone can be the driving force for an ultrafast migration of a positive charge created upon ionization of molecular systems. Here we show that this purely electronic phenomenon generates a characteristic IR radiation. The situation when the initial ionic wave packet is produced by a sudden removal of an electron is also studied. It is shown that in this case a much stronger UV emission is generated. This emission appears as an ultrafast response of the remaining electrons to the perturbation caused by the sudden ionization and as such is a universal phenomenon to be expected in every multielectron system.Comment: 5 pages, 4 figure

On the Cholesky Decomposition for electron propagator methods: General aspects and application on C60

To treat the electronic structure of large molecules by electron propagator methods we developed a parallel computer program called P-RICD$\Sigma$. The program exploits the sparsity of the two-electron integral matrix by using Cholesky decomposition techniques. The advantage of these techniques is that the error introduced is controlled only by one parameter which can be chosen as small as needed. We verify the tolerance of electron propagator methods to the Cholesky decomposition threshold and demonstrate the power of the P-RICD$\Sigma$ program for a representative example (C60). All decomposition schemes addressed in the literature are investigated. Even with moderate thresholds the maximal error encountered in the calculated electron affinities and ionization potentials amount to a few meV only, and the error becomes negligible for small thresholds.Comment: 30 pages, 6 figures submitted to J.Chem. Phy

On interacting fermions and bosons with definite total momentum

Any {\it exact} eigenstate with a definite momentum of a many-body Hamiltonian can be written as an integral over a {\it symmetry-broken} function $\Phi$. For two particles, we solve the problem {\it exactly} for all energy levels and any inter-particle interaction. Especially for the ground-state, $\Phi$ is given by the simple Hartree-Fock/Hartree ansatz for fermions/bosons. Implications for several and many particles as well as a numerical example are provided

Cold atoms in real-space optical lattices

Cold atoms in optical lattices are described in {\it real space} by multi-orbital mean-field Ans\"atze. In this work we consider four typical systems: (i) spinless identical bosons, (ii) spinor identical bosons (iii), Bose-Bose mixtures, and (iv) Bose-Fermi mixtures and derive in each case the corresponding multi-orbital mean-field energy-functional and working equations. The notions of {\it dressed} Wannier functions and Wannier spinors are introduced and the equations defining them are presented and discussed. The dressed Wannier functions are the set of orthogonal, translationally-equivalent orbitals which minimizes the energy of the Hamiltonian including boson-boson (particle-particle) interactions. Illustrative examples of dressed Wannier functions are provided for spinless bosonic atoms and mixtures in one-dimensional optical lattices.Comment: 27 pages, 4 figures; [version minus figures published