Near-Infrared Camera and Multi-Object Spectrometer Observations of the Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry

This paper presents data obtained during the NICMOS Guaranteed Time Observations of a portion of the Hubble Deep Field. The data are in a catalog format similar to the publication of the original WFPC2 Hubble Deep Field program (Williams et al.). The catalog contains 342 objects in a 49farcs1 × 48farcs4 subfield of the total observed field, 235 of which are considered coincident with objects in the WFPC2 catalog. The 3 σ signal-to-noise ratio level is at an aperture AB magnitude of approximately 28.8 at 1.6 μm. The catalog sources, listed in order of right ascension, are selected to satisfy a limiting signal-to-noise ratio criterion of greater than or equal to 2.5. This introduces a few false detections into the catalog, and users should take careful note of the completeness and reliability levels for the catalog discussed in §§ 9 and 10. The catalog also contains a test parameter indicating the results of half-catalog tests and the degree of coincidence with the original WFPC2 catalog

The NOAO Data Lab virtual storage system

Collaborative research/computing environments are essential for working with the next generations of large astronomical data sets. A key component of them is a distributed storage system to enable data hosting, sharing, and publication. VOSpace is a lightweight interface providing network access to arbitrary backend storage solutions and endorsed by the International Virtual Observatory Alliance (IVOA). Although similar APIs exist, such as Amazon S3, WebDav, and Dropbox, VOSpace is designed to be protocol agnostic, focusing on data control operations, and supports asynchronous and third-party data transfers, thereby minimizing unnecessary data transfers. It also allows arbitrary computations to be triggered as a result of a transfer operation: for example, a file can be automatically ingested into a database when put into an active directory or a data reduction task, such as Sextractor, can be run on it. In this paper, we shall describe the VOSpace implementations that we have developed for the NOAO Data Lab. These offer both dedicated remote storage, accessible as a local file system via FUSE, and a local VOSpace service to easily enable data synchronization

The NOAO Data Lab: Science-Driven Development

The NOAO Data Lab aims to provide infrastructure to maximize community use of the high-value survey datasets now being collected with NOAO telescopes and instruments. As a science exploration framework, the Data Lab allow users to access and search databases containing large (i.e. terabyte-scale) catalogs, visualize, analyze, and store the results of these searches, combine search results with data from other archives or facilities, and share these results with collaborators using a shared workspace and/or data publication service. In the process of implementing the needed tools and services, specific science cases are used to guide development of the system framework and tools. The result is a Year-1 capability demonstration that (fully or partially) implements each of the major architecture components in the context of a real-world science use-case. In this paper, we discuss how this model of science-driven development helped us to build a fully functional system capable of executing the chosen science case, and how we plan to scale this system to support general use in the next phase of the project

The NICMOS Ultra Deep Field: Observations, Data Reduction, and Galaxy Photometry

This paper describes the observations and data reduction techniques for the version 2.0 images and catalog of the NICMOS Ultra Deep Field Treasury program. All sources discussed in this paper are based on detections in the combined NICMOS F110W and F160W bands only. The NICMOS images are drizzled to 0.09 arc second pixels and aligned to the ACS UDF F850LP image which was rebinned to the same pixel scale. These form the NICMOS version 2.0 UDF images. The catalog sources are chosen with a conservative detection limit to avoid the inclusion of numerous spurious sources. The catalog contains 1293 objects in the 144 x 144 arc sececonds NICMOS subfield of the UDF. The 5 sigma signal to noise level is an average 0.6 arc second diameter aperture AB magnitude of ~27.7 at 1.1 and 1.6 microns. The catalog sources, listed in order of right ascension, satisfy a minimum signal to noise criterion of 1.4 sigma in at least 7 contiguous pixels of the combined F110W and F160W imageComment: Accepted for publication in the Astronomical Journal. 33 Pages, 6 Figure

Formation and Evolution of Planetary Systems: Cold Outer Disks Associated with Sun-like stars

We present the discovery of debris systems around three solar mass stars based upon observations performed with the Spitzer Space Telescope as part of a Legacy Science Program, ``the Formation and Evolution of Planetary Systems'' (FEPS). We also confirm the presence of debris around two other stars. All the stars exhibit infrared emission in excess of the expected photospheres in the 70 micron band, but are consistent with photospheric emission at <= 33 micron. This restricts the maximum temperature of debris in equilibrium with the stellar radiation to T < 70 K. We find that these sources are relatively old in the FEPS sample, in the age range 0.7 - 3 Gyr. Based on models of the spectral energy distributions, we suggest that these debris systems represent materials generated by collisions of planetesimal belts. We speculate on the nature of these systems through comparisons to our own Kuiper Belt, and on the likely planet(s) responsible for stirring the system and ultimately releasing dust through collisions. We further report observations of a nearby star HD 13974 (d =11 pc) that is indistinguishable from a bare photosphere at both 24 micron and 70 micron. The observations place strong upper limits on the presence of any cold dust in this nearby system (L_IR/L_* < 10^{-5.2}).Comment: 31 pages, 9 figures, accepted for publication in Ap

Formation and Evolution of Planetary Systems: Placing Our Solar System in Context with Spitzer

We summarize the progress to date of our Legacy Science Program entitled "The Formation and Evolution of Planetary Systems" (FEPS) based on observations obtained with the Spitzer Space Telescope during its first year of operation. In addition to results obtained from our ground-based preparatory program and our early validation program, we describe new results from a survey for near-infrared excess emission from the youngest stars in our sample as well as a search for cold debris disks around sun-like stars. We discuss the implications of our findings with respect to current understanding of the formation and evolution of our own solar system.Comment: 8 postscript pages including 3 figures. To appear in "Spitzer New Views of the Cosmos" ASP Conference Series, eds. L. Armus et al. FEPS website at http://feps.as.arizona.ed

Pushing the Envelope: Unleashing the Potential of High Contrast Imaging with HST

The complement of HST instruments provides a unique avenue for obtaining diraction limited optical/near-IR images with Strehl ratios unachievable with ground-based systems. Coupled with the much greater space-based stability of the telescope+instrument Point Spread Function, dierential imaging by PSF subtraction enables very high contrast imaging. This is further enhanced, signi cantly, by the coronagraphic systems in the second generation instruments NICMOS and STIS. The high dynamic range of the non-destructive multiple-readout data formats provided by the NICMOS detectors and read-out electronics are complementary in allowing observers to take advantage of these imaging capabilities. Exploiting the very high levels of background rejection achievable with these instrumental systems, while preserving their intrinsic photometric and astrometric ecacy, required the development of a new suite of integrated analysis tools (the NICMOS/IDT&apos;s IDP3 software) . Here we discuss some of the signi cant scienti c results obtained in the arena of extrasolar planet and disk imaging which has been advanced by the synthesis of these observing modes and analysis tools