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Register a new userNICMOS Observations of the Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry
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This paper contains a catlog of sources observed in a portion of the Hubble Deep Field by the NICMOS instrument. Methods of observation and data analysis are discussed. The catalog has two parts. The first is a listing of all sources with signal to noise ratios greater than or equal to 2.5. The second part contains sources with signal to noise ratios less than 2.5. The second part is intended for researchers who wish to know the limits to which sources may appear at a location.
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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 image
The Hubble Deep Field-South observations targeted a high-galactic-latitude field near QSO J2233-606. We present WFPC2 observations of the field in four wide bandpasses centered at roughly 300, 450, 606, and 814 nm. Observations, data reduction procedures, and noise properties of the final images are discussed in detail. A catalog of sources is presented, and the number counts and color distributions of the galaxies are compared to a new catalog of the HDF-N that has been constructed in an identical manner. The two fields are qualitatively similar, with the galaxy number counts for the two fields agreeing to within 20%. The HDF-S has more candidate Lyman-break galaxies at z > 2 than the HDF-N. The star-formation rate per unit volume computed from the HDF-S, based on the UV luminosity of high-redshift candidates, is a factor of 1.9 higher than from the HDF-N at z ~ 2.7, and a factor of 1.3 higher at z ~ 4.
We describe the design and data sample from the DEEP2 Galaxy Redshift Survey, the densest and largest precision-redshift survey of galaxies at z ~ 1 completed to date. The survey has conducted a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude M_B = -20 at z ~ 1 via ~90 nights of observation on the DEIMOS spectrograph at Keck Observatory. DEEP2 covers an area of 2.8 deg^2 divided into four separate fields, observed to a limiting apparent magnitude of R_AB=24.1. Objects with z < 0.7 are rejected based on BRI photometry in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ~2.5 times more efficiently than in a purely magnitude-limited sample. Approximately sixty percent of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets which fail to yield secure redshifts are blue objects that lie beyond z ~ 1.45. The DEIMOS 1200-line/mm grating used for the survey delivers high spectral resolution (R~6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. DEEP2 surpasses other deep precision-redshift surveys at z ~ 1 in terms of galaxy numbers, redshift accuracy, sample number density, and amount of spectral information. We also provide an overview of the scientific highlights of the DEEP2 survey thus far. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the publicly-available DEEP2 DEIMOS data reduction pipelines. [Abridged]
In this article we present deep, high-resolution radio interferometric observations at 153 MHz to complement the extensively studied NOAO Bootes field. We provide a description of the observations, data reduction and source catalog construction. From our single pointing GMRT observation of ~12 hours we obtain a high-resolution (26 x 22) image of ~11.3 square degrees, fully covering the Bootes field region and beyond. The image has a central noise level of ~1.0 mJy/beam, which rises to 2.0-2.5 mJy/beam at the field edge, placing it amongst the deepest ~150 MHz surveys to date. The catalog of 598 extracted sources is estimated to be ~92 percent complete for >10 mJy sources, while the estimated contamination with false detections is <1 percent. The low RMS position uncertainty of 1.24 facilitates accurate matching against catalogs at optical, infrared and other wavelengths. Differential source counts are determined down to <~10 mJy. There is no evidence for flattening of the counts towards lower flux densities as observed in deep radio surveys at higher frequencies, suggesting that our catalog is dominated by the classical radio-loud AGN population that explains the counts at higher flux densities. Combination with available deep 1.4 GHz observations yields an accurate determination of spectral indices for 417 sources down to the lowest 153 MHz flux densities, of which 16 have ultra-steep spectra with spectral indices below -1.3. We confirm that flattening of the median spectral index towards low flux densities also occurs at this frequency. The detection fraction of the radio sources in NIR Ks-band is found to drop with radio spectral index, which is in agreement with the known correlation between spectral index and redshift for brighter radio sources.
This paper presents the star formation history in the NICMOS Northern Deep HDF. It uses the techniques of photometric redshifts and extinctions to correct for extinction of the ultra-violet flux. It presents a new method for correcting for surface brightness diming. It also predicts the 850 micron fluxes of the objects for comparison with SCUBA measurements
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