HETDEX pilot survey for emission-line galaxies - I. Survey design, performance, and catalog

Source: arXiv

ABSTRACT We present a catalog of emission-line galaxies selected solely by their emission-line fluxes using a wide-field integral field spectrograph. This work is partially motivated as a pilot survey for the upcoming Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). We describe the observations, reductions, detections, redshift classifications, line fluxes, and counterpart information for 397 emission-line galaxies detected over 169 sq.arcmin with a 3500-5800 Ang. bandpass under 5 Ang. full-width-half-maximum (FWHM) spectral resolution. The survey's best sensitivity for unresolved objects under photometric conditions is between 4-20 E-17 erg/s/ depending on the wavelength, and Ly-alpha luminosities between 3-6 E42 erg/s are detectable. This survey method complements narrowband and color-selection techniques in the search for high redshift galaxies with its different selection properties and large volume probed. The four survey fields within the COSMOS, GOODS-N, MUNICS, and XMM-LSS areas are rich with existing, complementary data. We find 104 galaxies via their high redshift Ly-alpha emission at 1.9<z<3.8, and the majority of the remainder objects are low redshift [OII]3727 emitters at z<0.56. The classification between low and high redshift objects depends on rest frame equivalent width, as well as other indicators, where available. Based on matches to X-ray catalogs, the active galactic nuclei (AGN) fraction amongst the Ly-alpha emitters (LAEs) is 6%. We also analyze the survey's completeness and contamination properties through simulations. We find five high-z, highly-significant, resolved objects with full-width-half-maximum sizes >44 sq.arcsec which appear to be extended Ly-alpha nebulae. We also find three high-z objects with rest frame Ly-alpha equivalent widths above the level believed to be achievable with normal star formation, EW(rest)>240 Ang. Comment: 45 pages, 36 figures, 5 tables, submitted to ApJS


Available from: Eiichiro Komatsu, Jun 02, 2015
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    ABSTRACT: The tremendous success of the first edition of “Numerical recipes in FORTRAN. The art of scientific computing” (Cambridge University Press, 1986, Zbl 0587.65003) encouraged the authors to elaborate a second edition in the same spirit of readability and usefulness, having both the benefit of an increased experience and also a feedback from the readers. The new edition keeps the same accessible level of presentation and much more, this time, some of the topics are separated and labeled as “advanced” so that a very diverse category of readers can be addressed. It also provides over 300 FORTRAN routines (over 100 new ones and many upgraded versions of the original ones). Beside the chapters of the earlier edition (covering topics of a numerical analysis course – solution of linear algebraic equations, interpolation and extrapolation, evaluation and integration of functions, special functions, random numbers, sorting, root findings and nonlinear sets of equations, minimization or maximization of functions, eigensystems, integration of ordinary differential equations) a new chapter on integral equations and inverse methods and one on “less- numerical” algorithms are introduced, including Huffman and arithmetic coding and arbitrary precision arithmetic. The old chapters are enriched with new material such as the fast Fourier transform for real data in two and three dimensions, routines for banded diagonal linear systems, improved routines for linear algebra on sparse matrices and many others. Suitable for both an advanced undergraduate or a graduate course on numerical analysis for science or engineering majors and as professional reference, “Numerical recipes” represents a complete text and reference book on scientific computing. The Example book published by the same authors (Zbl 0587.65004) to accompany this book contains FORTRAN test- drivers for the presented programs. All the procedures listed in “Numerical recipes” are available from Cambridge University Press on diskettes for IBM compatible machines.Reviewer: O.Pastravanu (South Fort Worth)
    Mathematics of Computation 01/1992; DOI:10.2307/2153422 · 1.41 Impact Factor