We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). 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 large, wide-field ground-based system designed to obtain repeated images covering the sky visible from Cerro Pachón 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, a 3.2-gigapixel camera, and six filters (ugrizy) covering the wavelength range 320-1050 nm. The project is in the construction phase and will begin regular survey operations by 2022. About 90% of the observing time will be devoted to a deep-wide-fast survey mode that will uniformly observe a 18,000 deg 2 region about 800 times (summed over all six bands) during the anticipated 10 yr of operations and will yield a co-added map to r∼27.5. These data will result in databases including about 32 trillion observations of 20 billion galaxies and a similar number of stars, and they will serve the majority of the primary science programs. The remaining 10% of the observing time will be allocated to special projects such as Very Deep and Very Fast time domain surveys, whose details are currently under discussion. We illustrate how the LSST science drivers led to these choices of system parameters, and we describe the expected data products and their characteristics.

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Prepared by the LSST Science Collaborations, with contributions from the LSST Project. PrefaceMajor advances in our understanding of the Universe over the history of astronomy have often arisen from dramatic improvements in our ability to observe the sky to greater depth, in previously unexplored wavebands, with higher precision, or with improved spatial, spectral, or temporal resolution. Aided by rapid progress in information technology, current sky surveys are again changing the way we view and study the Universe, and the next-generation instruments, and the surveys that will be made with them, will maintain this revolutionary progress. Substantial progress in the important scientific problems of the next decade (determining the nature of dark energy and dark matter, studying the evolution of galaxies and the structure of our own Milky Way, opening up the time domain to discover faint variable objects, and mapping both the inner and outer Solar System) all require wide-field repeated deep imaging of the sky in optical bands.The wide-fast-deep science requirement leads to a single wide-field telescope and camera which can repeatedly survey the sky with deep short exposures. The Large Synoptic Survey Telescope (LSST), a dedicated telecope with an effective aperture of 6.7 meters and a field of view of 9.6 deg 2 , will make major contributions to all these scientific areas and more. It will carry out a survey of 20,000 deg 2 of the sky in six broad photometric bands, imaging each region of sky roughly 2000 times (1000 pairs of back-to-back 15-sec exposures) over a ten-year survey lifetime.The LSST project will deliver fully calibrated survey data to the United States scientific community and the public with no proprietary period. Near real-time alerts for transients will also be provided worldwide. A goal is worldwide participation in all data products. The survey will enable comprehensive exploration of the Solar System beyond the Kuiper Belt, new understanding of the structure of our Galaxy and that of the Local Group, and vast opportunities in cosmology and galaxy evolution using data for billions of distant galaxies. Since many of these science programs will involve the use of the world's largest non-proprietary database, a key goal is maximizing the usability of the data. Experience with previous surveys is that often their most exciting scientific results were unanticipated at the time that the survey was designed; we fully expect this to be the case for the LSST as well.The purpose of this Science Book is to examine and document in detail science goals, opportunities, and capabilities that will be provided by the LSST. The book addresses key questions that will be confronted by the LSST survey, and it poses new questions to be addressed by future study. It contains previously available material (including a number of White Papers submitted to the ASTRO2010 Decadal Survey) as well as new results from a year-long campaign of study and evaluation. This book does not attempt to be complete; there are many ...

We generate theoretical albedo and reflection spectra for a full range of extrasolar giant planet (EGP) models, from Jovian to 51-Pegasi class objects. Our albedo modeling utilizes the latest atomic and molecular cross sections, a Mie theory treatment of extinction by condensates, a variety of particle size distributions, and an extension of the Feautrier radiative transfer method which allows for a general treatment of the scattering phase function. We find that due to qualitative similarities in the compositions and spectra of objects within each of five broad effective temperature ranges, it is natural to establish five representative EGP albedo classes: a ``Jovian'' class (T$_{\rm eff} \lesssim 150$ K; Class I) with tropospheric ammonia clouds, a ``water cloud'' class (T$_{\rm eff} \sim 250$ K; Class II) primarily affected by condensed H$_2$O, a ``clear'' class (T$_{\rm eff} \gtrsim 350$ K; Class III) which lacks clouds, and two high-temperature classes: Class IV (900 K $\lesssim$ T$_{\rm{eff}}$ $\lesssim$ 1500 K) for which alkali metal absorption predominates, and Class V (T$_{\rm{eff}}$ $\gtrsim$ 1500 K and/or low surface gravity ($\lesssim$ 10$^3$ cm s$^{-2}$)) for which a high silicate layer shields a significant fraction of the incident radiation from alkali metal and molecular absorption. The resonance lines of sodium and potassium are expected to be salient features in the reflection spectra of Class III, IV, and V objects. We derive Bond albedos and effective temperatures for the full set of known EGPs and explore the possible effects of non-equilibrium condensed products of photolysis above or within principal cloud decks. As in Jupiter, such species can lower the UV/blue albedo substantially, even if present in relatively small mixing ratios.Comment: revised LaTeX manuscript accepted to Ap.J.; also available at http://jupiter.as.arizona.edu/~burrows/paper

We present results from dynamical models of core-collapse supernovae in one spatial dimension, employing a newly-developed Boltzmann neutrino radiation transport algorithm, coupled to Newtonian Lagrangean hydrodynamics and a consistent high-density nuclear equation of state. The transport method is multi-group, employs the Feautrier technique, uses the tangent-ray approach to resolve angles, is implicit in time, and is second-order accurate in space. We focus on shock breakout and follow the dynamical evolution of the cores of 11 M ⊙ , 15 M ⊙ , and 20 M ⊙ progenitors through collapse and the first 250 milliseconds after bounce. The shock breakout burst is the signal event in core-collapse evolution, is the brightest phenomenon in astrophysics, and is largely responsible for the initial debilitation and stagnation of the bounce shock. As such, its detection and characterization could test fundamental aspects of the current collapse/supernova paradigm. We examine the effects on the emergent neutrino spectra, light curves, and mix of species (particularly in the early post-bounce epoch) of artificial opacity changes, the number of energy groups, the weak magnetism/recoil corrections, nucleon-nucleon bremsstrahlung, neutrino-electron scattering, and the compressibility of nuclear matter. Furthermore, we present the first highresolution look at the angular distribution of the neutrino radiation field both in the semi-transparent regime and at large radii and explore the accuracy with which our tangent-ray method tracks the free propagation of a pulse of radiation in a near vacuum. Finally, we fold the emergent neutrino spectra with the efficiencies and detection processes for a selection of modern underground neutrino observatories and argue that the prompt electron-neutrino breakout burst from the next galactic supernova is in principle observable and usefully diagnostic of fundamental collapse/supernova behavior. Though we are not in this study focusing on the supernova mechanism per se, our simulations support the theoretical conclusion (already reached by others) that spherical (1D) supernovae do not explode when good physics and transport methods are employed.

We present optical and infrared spectroscopy of the Ðrst 2 months of evolution of the Type II supernova SN 1999em. We combine these data with high-quality optical/infrared photometry beginning only 3 days after shock breakout, in order to study the performance of the "" expanding photosphere method ÏÏ (EPM) in the determination of distances. With this purpose, we develop a technique to measure accurate photospheric velocities by cross-correlating observed and model spectra. The application of this technique to SN 1999em shows that we can reach an average uncertainty of 11% in velocity from an individual spectrum. Our analysis shows that EPM is quite robust to the e †ects of dust. In particular, the distances derived from the V I Ðlters change by only 7% when the adopted visual extinction in the host galaxy is varied by 0.45 mag. The superb time sampling of the BV IZJHK light curves of SN 1999em permits us to study the internal consistency of EPM and test the dilution factors computed from atmosphere models for Type II plateau supernovae. We Ðnd that, in the Ðrst week since explosion, the EPM distances are up to 50% lower than the average, possibly because of the presence of circumstellar material. Over the following 65 days, on the other hand, our tests lend strong credence to the atmosphere models, and conÐrm previous claims that EPM can produce consistent distances without having to craft speciÐc models to each supernova. This is particularly true for the V I Ðlters, which yield dis- tances with an internal consistency of 4%. From the whole set of BV IZJHK photometry, we obtain an average distance of 7.5^0.5 Mpc, where the quoted uncertainty (7%) is a conservative estimate of the internal precision of the method obtained from the analysis of the Ðrst 70 days of the supernova evolution.

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We present evidence for a correlation between expansion velocities of the ejecta of Type II plateau supernovae and their bolometric luminosities during the plateau phase. This correlation permits one to standardize the candles and decrease the scatter in the Hubble diagram from ∼1 mag to levels of 0.4 and 0.3 mag in the V and I bands, respectively. When we restrict the sample to the eight objects that are well in the Hubble flow ( km s Ϫ1), cz 1 3000 the scatter drops even further, to only 0.2 mag (or 9% in distance), which is comparable to the precision yielded by Type Ia supernovae and is far better than the "expanding photosphere method" applied to Type II supernovae. Using SN 1987A to calibrate the Hubble diagrams, we get . H p 55 ‫ע‬ 12 0