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A report providing an update on the state of the research on testing accommodations as well as to identify promising future areas of research. Previous reports by NCEO have covered research published since 1999. NCEO summarizes the research to review current research trends and enhance understanding of the implications of accommodations use in the development of future policy directions, implementation of current and new accommodations, and valid and reliable interpretations when accommodations are used in testing situations. For 2011 and 2012, 49 published research studies on the topic of testing accommodations were found. The studies in 2011-2012 demonstrated several similarities when viewing them in comparison with previous research, especially in relation to the 2009-2010 studies examined in NCEO's previous accommodations research review.

To date, asteroseismology has provided core to surface differential rotation measurements in eight main-sequence stars. These stars, ranging in mass from $\sim$1.5-9$M_\odot$, show rotation profiles ranging from uniform to counter-rotation. Although they have a variety of masses, these stars all have convective cores and overlying radiative regions, conducive to angular momentum transport by internal gravity waves (IGW). Using two-dimensional (2D) numerical simulations we show that angular momentum transport by IGW can explain all of these rotation profiles. We further predict that should high mass, faster rotating stars be observed, the core to envelope differential rotation will be positive, but less than one., Comment: 5 pages, Accepted at ApJL

We present a C-language implementation of the lambda-pi calculus by extending the (call-by-need) stack machine of Ariola, Chang and Felleisen to hold types, using a typeless- tagless- final interpreter strategy. It has the advantage of expressing all operations as folds over terms, including by-need evaluation, recovery of the initial syntax-tree encoding for any term, and eliminating most garbage-collection tasks. These are made possible by a disciplined approach to handling the spine of each term, along with a robust stack-based API. Type inference is not covered in this work, but also derives several advantages from the present stack transformation. Timing and maximum stack space usage results for executing benchmark problems are presented. We discuss how the design choices for this interpreter allow the language to be used as a high-level scripting language for automatic distributed parallel execution of common scientific computing workflows., Comment: Submitted Version, 8 pages, 5 figures

We demonstrate observational evidence for the occurrence of convectively driven internal gravity waves (IGW) in young massive O-type stars observed with high-precision CoRoT space photometry. This evidence results from a comparison between velocity spectra based on 2D hydrodynamical simulations of IGW in a differentially-rotating massive star and the observed spectra.We also show that the velocity spectra caused by IGW may lead to detectable line-profile variability and explain the occurrence of macroturbulence in the observed line profiles of OB stars. Our findings provide predictions that can readily be tested by including a sample of bright slowly and rapidly rotating OB-type stars in the scientific programme of the K2 mission accompanied by high-precision spectroscopy and their confrontation with multi-dimensional hydrodynamic simulations of IGW for various masses and ages., Comment: 4 pages, 3 figures, accepted for publication in The Astrophysical Journal Letters

An extensive study of the level structure of 61Co has been performed following the complex 26Mg(48Ca, 2a4npg)61Co reaction at beam energies of 275, 290 and 320 MeV using Gammasphere and the Fragment Mass Analyzer (FMA). The low-spin structure is discussed within the framework of shell-model calculations using the GXPF1A effective interaction. Two quasi-rotational bands consisting of stretched-E2 transitions have been established up to spins I = 41/2 and (43/2), and excitation energies of 17 and 20 MeV, respectively. These are interpreted as signature partners built on a neutron {\nu}(g9/2)2 configuration coupled to a proton {\pi}p3/2 state, based on Cranked Shell Model (CSM) calculations and comparisons with observations in neighboring nuclei. In addition, four I = 1 bands were populated to high spin, with the yrast dipole band interpreted as a possible candidate for the shears mechanism, a process seldom observed thus far in this mass region.

This work presents a general unifying theoretical framework for quantum non-equilibrium systems. It is based on a re-statement of the dynamical problem as one of inferring the distribution of collision events that move a system toward thermal equilibrium from an arbitrary starting distribution. Using a form based on maximum entropy for this transition distribution leads to a statistical description of open quantum systems with strong parallels to the conventional, maximum-entropy, equilibrium thermostatics. A precise form of the second law of thermodynamics can be stated for this dynamics at every time-point in a trajectory. Numerical results are presented for low-dimensional systems interacting with cavity fields. The dynamics and stationary state are compared to a reference model of a weakly coupled oscillator plus cavity supersystem thermostatted by periodic partial measurements. Despite the absence of an explicit cavity in the present model of open quantum dynamics, both the relaxation rates and stationary state properties closely match the reference. Additionally, the time-course of energy exchange and entropy increase is given throughout an entire measurement process for a single spin system. The results show the process to be capable of initially absorbing heat when starting from a superposition state, but not from an isotropic distribution. Based on these results, it is argued that logical inference in the presence of environmental noise is sufficient to resolve the paradox of wavefunction collapse., Comment: 17 pages, 7 figures, 4 sleepless nights - presented at the APS March Meeting, 2015

A very exotic decay mode at the proton drip-line, $\beta$-delayed $\gamma$-proton decay, has been observed in the $\beta$ decay of the $T_z$ = -2 nucleus $^{56}$Zn. Three $\gamma$-proton sequences have been observed following the $\beta$ decay. The fragmentation of the IAS in $^{56}$Cu has also been observed for the first time. The results were reported in a recent publication. At the time of publication the authors were puzzled by the competition between proton and $\gamma$ decays from the main component of the IAS. Here we outline a possible explanation based on the nuclear structure properties of the three nuclei involved, namely $^{56}$Zn, $^{56}$Cu and $^{55}$Ni, close to the doubly magic nucleus $^{56}$Ni. From the fragmentation of the Fermi strength and the excitation energy of the two populated 0$^{+}$ states we could deduce the off-diagonal matrix element of the charge-dependent part of the Hamiltonian responsible for the mixing. These results are compared with the decay of $^{55}$Cu with one proton less than $^{56}$Zn. For completeness we summarise the results already published., Comment: Proceedings of the 2nd Conference on Advances in Radioactive Isotope Science ARIS2014. 6 pages, 4 figures

A study of the $\beta$ decay of the proton-rich $T_{z}$ = -2 nucleus $^{56}$Zn has been reported in a recent publication. A rare and exotic decay mode, $\beta$-delayed $\gamma$-proton decay, has been observed there for the first time in the $fp$ shell. Here we expand on some of the details of the data analysis, focussing on the charged particle spectrum., Comment: Proceedings of the Zakopane Conference on Nuclear Physics 2014 "Extremes of the Nuclear Landscape". 4 pages, 4 figures

Multipolar expansions are a foundational tool for describing basis functions in quantum mechanics, many-body polarization, and other distributions on the unit sphere. Progress on these topics is often held back by complicated and competing formulas for calculating and using spherical harmonics. We present a complete representation for supersymmetric 3D tensors that replaces spherical harmonic basis functions by a dramatically simpler set of weights associated to discrete points in 3D space. This representation is shown to be space optimal. It reduces tensor contraction and the spherical harmonic decomposition of Poisson's operator to pairwise summations over the point set. Moreover, multiplication of spherical harmonic basis functions translates to a direct product in this representation., Comment: 12 pages, 4 figures, presented at Southeast Regional Meeting of the Amer. Chem. Soc., October 2014

We present magnetohydrodynamic (MHD) simulations of the atmospheres of hot Jupiters ranging in temperature from 1100-1800K. Magnetic effects are negligible in atmospheres with temperatures $\lesssim$ 1400K. At higher temperatures winds are variable and in many cases, mean equatorial flows can become westward, opposite to their hydrodynamic counterparts. Ohmic dissipation peaks at temperatures $\sim$1500-1600K, depending on field strength, with maximum values $\sim 10^{18}$W at 10bar, substantially lower than previous estimates. Based on the limited parameter study done, this value can not be increased substantially with increasing winds, higher temperatures, higher field strengths, different boundary conditions or lower diffusivities. Although not resolved in these simulations there is modest evidence that a magnetic buoyancy instability may proceed in hot atmospheres., Comment: 13 pages, 13 figures, Accepted to ApJ

We show that ratios of light-particle energy spectra display scaling properties that can be accu- rately described by effective local chemical potentials. This demonstrates the equivalence of t/3He and n/p spectral ratios and provides an essential test of theoretical predictions of isotopically resolved light-particle spectra. In addition, this approach allows direct comparisons of many theoretical n/p spectral ratios to experiments where charged-particle spectra but not neutron spectra are accurately measured. Such experiments may provide much more quantitative constraints on the density and momentum dependence of the symmetry energy.

Spectroscopic information has been extracted on the hole-states of $^{55}$Ni, the least known of the quartet of nuclei ($^{55}$Ni, $^{57}$Ni, $^{55}$Co and $^{57}$Co), one neutron away from $^{56}$Ni, the N=Z=28 double magic nucleus. Using the $^{1}$H($^{56}$Ni,d)$^{55}$Ni transfer reaction in inverse kinematics, neutron spectroscopic factors, spins and parities have been extracted for the f$_{7/2}$, p$_{3/2}$ and the s$_{1/2}$ hole-states of $^{55}$Ni. This new data provides a benchmark for large basis calculations that include nucleonic orbits in both the sd and pf shells. State of the art calculations have been performed to describe the excitation energies and spectroscopic factors of the s$_{1/2}$ hole-state below Fermi energy., Comment: Submitted to PLB

We report the observation of a very exotic decay mode at the proton drip-line, the $\beta$-delayed $\gamma$-proton decay, clearly seen in the $\beta$ decay of the $T_z$ = -2 nucleus $^{56}$Zn. Three $\gamma$-proton sequences have been observed after the $\beta$ decay. Here this decay mode, already observed in the $sd$-shell, is seen for the first time in the $fp$-shell. Both $\gamma$ and proton decays have been taken into account in the estimation of the Fermi (F) and Gamow Teller (GT) strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found., Comment: Accepted for publication in PRL. (5 pages, 4 figures)

We present the first three-dimensional magnetohydrodynamic (MHD) simulations of the atmosphere of HD 209458b which self-consistently include reduction of winds due to the Lorentz force and Ohmic heating. We find overall wind structures similar to that seen in previous models of hot Jupiter atmospheres, with strong equatorial jets and meridional flows poleward near the day side and equatorward near the night side. Inclusion of magnetic fields slows those winds and leads to Ohmic dissipation. We find wind slowing ranging from 10%-40% for reasonable field strengths. We find Ohmic dissipation rates ~10^17 W at 100 bar, orders of magnitude too small to explain the inflated radius of this planet. Faster wind speeds, not achievable in these anelastic calculations, may be able to increase this value somewhat, but likely will not be able to close the gap necessary to explain the inflated radius. We demonstrate that the discrepancy between the simulations presented here and previous models is due to inadequate treatment of magnetic field geometry and evolution. Induced poloidal fields become much larger than those imposed, highlighting the need for a self-consistent MHD treatment of these hot atmospheres., Comment: 6 pages, 4 figures, accepted at ApJL

A system of two microchannel-plate detectors has been successfully implemented for tracking projectile-fragmentation beams. The detectors provide interaction positions, angles, and arrival times of ions at the reaction target. The current design is an adaptation of an assembly used for low-energy beams ($\sim$1.4 MeV/nucleon). In order to improve resolution in tracking high-energy heavy-ion beams, the magnetic field strength between the secondary-electron accelerating foil and the microchannel plate had to be increased substantially. Results from an experiment using a 37-MeV/nucleon ${}^{56}$Ni beam show that the tracking system can achieve sub-nanosecond timing resolution and a position resolution of $\sim$1 mm for beam intensities up to $5\times10^{5}$ pps.