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The Gemini Planet Imager (GPI) is a complex optical system designed to directly detect the self-emission of young planets within two arcseconds of their host stars. After suppressing the starlight with an advanced AO system and apodized coronagraph, the dominant residual contamination in the focal plane are speckles from the atmosphere and optical surfaces. Since speckles are diffractive in nature their positions in the field are strongly wavelength dependent, while an actual companion planet will remain at fixed separation. By comparing multiple images at different wavelengths taken simultaneously, we can freeze the speckle pattern and extract the planet light adding an order of magnitude of contrast. To achieve a bandpass of 20%, sufficient to perform speckle suppression, and to observe the entire two arcsecond field of view at diffraction limited sampling, we designed and built an integral field spectrograph with extremely low wavefront error and almost no chromatic aberration. The spectrograph is fully cryogenic and operates in the wavelength range 1 to 2.4 microns with five selectable filters. A prism is used to produce a spectral resolution of 45 in the primary detection band and maintain high throughput. Based on the OSIRIS spectrograph at Keck, we selected to use a lenslet-based spectrograph to achieve an rms wavefront error of approximately 25 nm. Over 36,000 spectra are taken simultaneously and reassembled into image cubes that have roughly 192x192 spatial elements and contain between 11 and 20 spectral channels. The primary dispersion prism can be replaced with a Wollaston prism for dual polarization measurements. The spectrograph also has a pupil-viewing mode for alignment and calibration., Comment: 13 pages, 10 figures. Proceedings of the SPIE, 9147-55

The Census Bureau has historically grouped high school diploma holders along with those who hold "high school equivalent" credentials. Among these is the credential earned through successfully passing the General Education Development (GED) test. Interest in identifying those with GEDs has recently increased, in part from debate within the academic and federal statistical communities about the inclusion of high school equivalency degrees in the calculations of high school graduation, and because of the increasing concern that equivalency degrees are not truly equivalent in terms of labor market value and as a basis for future educational attainment (Heckman and LaFontaine, 2010; Murnane, Willett, and Tyler, 2000; Clark and Jaeger, 2006; Michel and Roy, 2006; Boesel, Alsalam, and Smith, 1998; Cameron and Heckman, 1993). This paper outlines the ways that the Census Bureau captures persons with alternative high school credentials, provides estimates of prevalence based on these different methods, compares these estimates to administrative records, and reviews the Census Bureau studies on the relative reliability of survey items on high school credentials. Appended are: (1) Question Wording for Surveys; and (2) Memo on GED Data Collection in Basic CPS 2007 to Present. (Contains 2 tables, 1 figure and 7 footnotes.)

This report discusses school enrollment levels and trends in the population aged 3 and older based on data collected in 2006 by the U.S. Census Bureau in the American Community Survey (ACS) and the Current Population Survey (CPS). Historically, the CPS has been the only data source used to produce school enrollment reports. This is the first report to show data from the ACS, supplemented with CPS data where they provide better information. The ACS has a larger sample size and will provide statistics for small levels of geography, which are reasons why it is used as a main source of enrollment data. Highlights of the report are: (1) In 2006, compared with the enrollment distribution of 2000, there were more students in college and high school and fewer in nursery, kindergarten, and elementary school; (2) High school dropouts constituted 11 percent of the population aged 18 to 24 years old; (3) More women than men are enrolled in college, and this has been true since 1979. Women have also become the majority of graduate students; (4) Diversity plays a prominent role among the school population, with differences apparent by geography. In the Western region of the United States, native non-Hispanic Whites were the minority among students enrolled in kindergarten through twelfth grade; and (5) Also in the Western region of the United States, over one-third of students enrolled in kindergarten through twelfth grade spoke a language other than English at home. Comparison of Census Bureau Data Sources on School Enrollment is appended. (Contains 6 figures, 2 tables and 18 footnotes.)

The Infra-Red Imaging Spectrograph (IRIS) is one of the three first light instruments for the Thirty Meter Telescope (TMT) and is the only one to directly sample the diffraction limit. The instrument consists of a parallel imager and off-axis Integral Field Spectrograph (IFS) for optimum use of the near infrared (0.84um-2.4um) Adaptive Optics corrected focal surface. We present an overview of the IRIS spectrograph that is designed to probe a range of scientific targets from the dynamics and morphology of high-z galaxies to studying the atmospheres and surfaces of solar system objects, the latter requiring a narrow field and high Strehl performance. The IRIS spectrograph is a hybrid system consisting of two state of the art IFS technologies providing four plate scales (4mas, 9mas, 25mas, 50mas spaxel sizes). We present the design of the unique hybrid system that combines the power of a lenslet spectrograph and image slicer spectrograph in a configuration where major hardware is shared. The result is a powerful yet economical solution to what would otherwise require two separate 30m-class instruments., Comment: 15 pages, 11 figures

We present a conceptual design for the atmospheric dispersion corrector (ADC) for TMT's Infrared Imaging Spectrograph (IRIS). The severe requirements of this ADC are reviewed, as are limitations to observing caused by uncorrectable atmospheric effects. The requirement of residual dispersion less than 1 milliarcsecond can be met with certain glass combinations. The design decisions are discussed and the performance of the design ADC is described. Alternative options and their performance tradeoffs are also presented., Comment: SPIE Astronomical Instrumentation 2010

One important frontier for astronomical adaptive optics (AO) involves methods such as Multi-Object AO and Multi-Conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key emphasis over the next decade will be to push astronomical AO to visible wavelengths. We have conducted the first laboratory simulations of wide-field, laser guide star adaptive optics at visible wavelengths on a 10-meter-class telescope. These experiments, utilizing the UCO/Lick Observatory's Multi-Object / Laser Tomography Adaptive Optics (MOAO/LTAO) testbed, demonstrate new techniques in wavefront sensing and control that are crucial to future on-sky MOAO systems. We (1) test and confirm the feasibility of highly accurate atmospheric tomography with laser guide stars, (2) demonstrate key innovations allowing open-loop operation of Shack-Hartmann wavefront sensors (with errors of ~30 nm) as will be needed for MOAO, and (3) build a complete error budget model describing system performance. The AO system maintains a performance of 32.4% Strehl on-axis, with 24.5% and 22.6% at 10" and 15", respectively, at a science wavelength of 710 nm (R-band) over the equivalent of 0.8 seconds of simulation. The MOAO-corrected field of view is ~25 times larger in area than that limited by anisoplanatism at R-band. Our error budget is composed of terms verified through independent, empirical experiments. Error terms arising from calibration inaccuracies and optical drift are comparable in magnitude to traditional terms like fitting error and tomographic error. This makes a strong case for implementing additional calibration facilities in future AO systems, including accelerometers on powered optics, 3D turbulators, telescope and LGS simulators, and external calibration ports for deformable mirrors., Comment: 29 pages, 11 figures, submitted to PASP

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world., Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overview

Home schooling has the potential to greatly impact the education system but has received little attention compared to other educational trends. This report draws on the 1994 October Current Population Survey and the 1996 and 1999 National Household Education Surveys (NHES) to determine the extent of home schooling and the social, demographic, and geographic characteristics of households that engage in home schooling. Analyses indicate that home schooling is less prevalent than shown in earlier estimates but has large potential for growth. In 1999, an estimated 790,000 children aged 6-17 were schooled at home, and the number was apparently growing. Home schoolers were likely to be non-Hispanic whites, but racial differences may be fading. Households with home-schooled children tended to include two adults with moderate to high education, with one either not in the labor force or working part-time. Home schoolers were more likely to be located in places that have been destinations for internal migration. Using a division of the country based on migration patterns, home schoolers were most prevalent in rural and suburban areas of the West that have received migration streams from California and other immigration gateway states, and in rural areas of "immigrant melting pot" states. About half of parents felt that they could provide a better education at home, while 30-33 percent were motivated by religious reasons or a poor learning environment at school. (Contains 29 references and 6 tables.) (SV)

A combination of high-resolution and wide-field imaging reveals two binary stars and one triple star system among the sample of the first 11 stars with planets detected by radial velocity variations. High resolution speckle or adaptive optics (AO) data probe subarcsecond scales down to the diffraction limit of the Keck 10-m or Lick 3-m, and direct images or AO images are sensitive to a wider field, extending to 10" or 38", depending upon the camera. One of the binary systems -- HD 114762 -- was not previously known to be a spatially resolved multiple system; additional data taken with the combination of Keck adaptive optics and NIRSPEC are used to characterize the new companion. The second binary system -- Tau Boo -- was a known multiple with two conflicting orbital solutions; the current data will help constrain the discrepant estimates of periastron time and separation. Another target -- 16 Cyg B -- was a known common proper motion binary, but the current data resolve a new third component, close to the wide companion 16 Cyg A. Both the HD 114762 and 16 Cyg B systems harbor planets in eccentric orbits, while the Tau Boo binary contains an extremely close planet in a tidally-circularized orbit. Although the sample is currently small, the proportion of binary systems is comparable to that measured in the field over a similar separation range. Incorporating the null result from another companion search project lowers the overall fraction of planets in binary systems, but the detections in our survey reveal that planets can form in binaries separated by less than 50 AU., Comment: 5 Tables, 16 Figures. ApJ, accepted