A Multi-Epoch HST Study of the Herbig-Haro Flow from XZ Tauri

We present nine epochs of Hubble Space Telescope optical imaging of the bipolar outflow from the pre-main sequence binary XZ Tauri. Our data monitors the system from 1995-2005 and includes emission line images of the flow. The northern lobe appears to be a succession of bubbles, the outermost of which expanded ballistically from 1995-1999 but in 2000 began to deform and decelerate along its forward edge. It reached an extent of 6" from the binary in 2005. A larger and fainter southern counterbubble was detected for the first time in deep ACS images from 2004. Traces of shocked emission are seen as far as 20" south of the binary. The bubble emission nebulosity has a low excitation overall, as traced by the [S II]/H-alpha line ratio, requiring a nearly comoving surrounding medium that has been accelerated by previous ejections or stellar winds. Within the broad bubbles there are compact emission knots whose alignments and proper motions indicate that collimated jets are ejected from each binary component. The jet from the southern component, XZ Tau A, is aligned with the outflow axis of the bubbles and has tangential knot velocities of 70-200 km/s. Knots in the northern flow are seen to slow and brighten as they approach the forward edge of the outermost bubble. The knots in the jet from the other star, XZ Tau B, have lower velocities of ~100 km/s

End-to-end simulation of high-contrast imaging systems: methods and results for the PICTURE mission family

We describe a set of numerical approaches to modeling the performance of spaceflight high-contrast imaging payloads. Mission design for high-contrast imaging requires numerical wavefront error propagation to ensure accurate component specifications. For constructed instruments, wavelength and angle-dependent throughput and contrast models allow detailed simulations of science observations, allowing mission planners to select the most productive science targets. The PICTURE family of missions seek to quantify the optical brightness of scattered light from extrasolar debris disks via several high-contrast imaging techniques: sounding rocket (the Planet Imaging Concept Testbed Using a Rocket Experiment) and balloon flights of a visible nulling coronagraph, as well as a balloon flight of a vector vortex coronagraph (the Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph, PICTURE-C). The rocket mission employs an on-axis 0.5m Gregorian telescope, while the balloon flights will share an unobstructed off-axis 0.6m Gregorian. This work details the flexible approach to polychromatic, end-to-end physical optics simulations used for both the balloon vector vortex coronagraph and rocket visible nulling coronagraph missions. We show the preliminary PICTURE-C telescope and vector vortex coronagraph design will achieve 10−8 contrast without post-processing as limited by realistic optics, but not considering polarization or low-order errors. Simulated science observations of the predicted warm ring around Epsilon Eridani illustrate the performance of both missions.NNG05WC17G, NNX11AD53G, and NNX15AG23

Algorithm implementation on the Navier-Stokes computer

The Navier-Stokes Computer is a multi-purpose parallel-processing supercomputer which is currently under development at Princeton University. It consists of multiple local memory parallel processors, called Nodes, which are interconnected in a hypercube network. Details of the procedures involved in implementing an algorithm on the Navier-Stokes computer are presented. The particular finite difference algorithm considered in this analysis was developed for simulation of laminar-turbulent transition in wall bounded shear flows. Projected timing results for implementing this algorithm indicate that operation rates in excess of 42 GFLOPS are feasible on a 128 Node machine

Numerical simulation of channel flow transition, resolution requirements and structure of the hairpin vortex

Three-dimensional, nonlinear numerical simulations are presented for the K-type and H-type transitions for channel flow. There are two objectives. The first is to establish firmly the resolution requirements for the various stages in the transition process. Comparisons between calculations on various grids suggest a set of guidelines for maintaining a physically meaningful calculation. The second objective is to map out the structure of the hairpin vortices which arise in K-type and H-type transitions in channel flow, to the latest stage currently feasible. Flow field details are presented for both a subcritical Reynolds number of 1500 and a supercritical Reynolds number of 8000. The diagnostics include illustrations of the vertical shear, streamwise and spanwise vorticity, helicity, vortex stretching, and vortex diffusion fields

タイの金融政策の分析 : ニューケインジアン確率的動学一般均衡モデルのベイジアン推定

政策分析プログラム / Policy Analysis Program政策研究大学院大学 / National Graduate Institute for Policy Studies論文審査委員: Roberto Leon-Gonzalez (主査), Minchung Hsu, Ponpoje Porapakkarm, Tetsushi Sonobe, Ippei Fujiwara (Keio University

Standard FITS template for simulated astrophysical scenes with the WFIRST coronagraph

The science investigation teams (SITs) for the WFIRST coronagraphic instrument have begun studying the capabilities of the instrument to directly image reflected light off from exoplanets at contrasts down to contrasts of ~10^-9 with respect to the stellar flux. Detection of point sources at these high contrasts requires yield estimates and detailed modeling of the image of the planetary system as it propagates through the telescope optics. While the SITs might generate custom astrophysical scenes, the integrated model, propagated through the internal speckle field, is typically done at JPL. In this white paper, we present a standard file format to ensure a single distribution system between those who produce the raw astrophysical scenes, and JPL modelers who incorporate those scenes into their optical modeling. At its core, our custom file format uses FITS files, and incorporates standards on packaging astrophysical scenes. This includes spectral and astrometric information for planetary and stellar point sources, zodiacal light and extragalactic sources that may appear as contaminants. Adhering to such a uniform data distribution format is necessary, as it ensures seamless work flow between the SITs and modelers at JPL for the goals of understanding limits of the WFIRST coronagraphic instrument.Comment: 8 pages, white pape

Community Input on an Enhanced Care Planning Tool Addressing Health Behaviors, Mental Health Needs, and Social Risks

Background: Many patients with multiple chronic conditions (MCC) have social risks, mental health needs, and/or unhealthy behaviors. These interfere with their ability to manage their MCC. A care planning tool was created to help address these needs; this study solicited feedback from stakeholder groups and incorporated it into improving the tool. Methods: Instrument: The Enhanced Care Planning (ECP) tool screens patients for social risks, mental health needs, and unhealthy behaviors. They are shown where their responses revealed risk, then select 1-2 to improve upon. Next, patients set personal goals and select strategies to support them. Patients are supported by the clinical care team and a community health worker to connect them to community resources. Procedures: Four stakeholder groups provided feedback on the ECP tool: community members, community service professionals (CSPs), researchers, and patients. A community review board of community members reviewed the ECP process. Researchers and CSPs then reviewed ECP content. Feedback was incorporated into revisions of the ECP content and process, then patients provided final feedback. Results: All stakeholder groups provided unique feedback. Community members desired visuals, the ability to individualize and receive support throughout the process. Researchers and CSPs recommended removing jargon. While researchers were interested in specific evidence-based strategies, CSPs suggested strategies with anecdotal support. Patients expressed positive overall impressions of the tool, interest in using it, and increased awareness of domains that influence their health. Conclusion: Feedback from all groups significantly altered the ECP tool’s design, and is likely to improve its usability and impact.https://scholarscompass.vcu.edu/gradposters/1109/thumbnail.jp