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تسجيل مستخدم جديدThe 2.4 $mu$m Galaxy Luminosity Function as Measured Using WISE. II. Sample Selection
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The WISE satellite surveyed the entire sky multiple times in four infrared (IR) wavelengths ($3.4, 4.6, 12,$ and $22, mu$m, Wright et al. 2010). This all-sky IR photometric survey makes it possible to leverage many of the large publicly available spectroscopic redshift surveys to measure galaxy properties in the IR. While characterizing the cross-matching of WISE data to a single survey is a straightforward process, doing it with six different redshift surveys takes a fair amount of space to characterize adequately, because each survey has unique caveats and characteristics that need addressing. This work describes a data set that results from matching five public redshift surveys with the AllWISE data release, along with a reanalysis of the data described in Lake et al. 2012. The combined data set has an additional flux limit of $80,mu$Jy ($19.14$ AB mag) in WISEs W1 filter imposed in order to limit it to targets with high completeness and reliable photometry in the AllWISE data set. Consistent analysis of all of the data is only possible if the color bias discussed in Ilbert et al. (2004) is addressed (for example: the techniques explored in the first paper in this series Lake et al. 2017b). The sample defined herein is used in this papers sequel paper, Lake et al. 2017a), to measure the luminosity function of galaxies at $2.4, mu$m rest frame wavelength, and the selection process of the sample is optimized for this purpose.
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The WISE satellite surveyed the entire sky multiple times in four infrared wavelengths (3.4, 4.6, 12, and $22,mu$m; Wright et al. 2010). The unprecedented combination of coverage area and depth gives us the opportunity to measure the luminosity funct
ion of galaxies, one of the fundamental quantities in the study of them, at $2.4 mu$m to an unparalleled level of formal statistical accuracy in the near infrared. The big advantage of measuring luminosity functions at wavelengths in the window $approx 2$ to $3.5,mu$m is that it correlates more closely to the total stellar mass in galaxies than others. In this paper we report on the parameters for the $2.4,mu$m luminosity function of galaxies obtained from applying the spectroluminosity functional based methods defined in Lake et al. (2017b) to the data sets described in Lake et al. (2017a) using the mean and covariance of $2.4,mu$m normalized SEDs from Lake & Wright (2016). In terms of single Schechter function parameters evaluated at the present epoch, the combined result is: $phi_star = 5.8 pm [0.3_{mathrm{stat}},, 0.3_{mathrm{sys}}] times 10^{-3} operatorname{Mpc}^{-3}$, $L_star = 6.4 pm [0.1_{mathrm{stat}},, 0.3_{mathrm{sys}}] times 10^{10}, L_{2.4,mumathrm{m},odot}$ ($M_star = -21.67 pm [0.02_{mathrm{stat}},, 0.05_{mathrm{sys}}]operatorname{AB mag}$), and $alpha = -1.050 pm [0.004_{mathrm{stat}},, 0.03_{mathrm{sys}}]$, corresponding to a galaxy number density of $0.08operatorname{Mpc}^{-3}$ brighter than $10^6, L_{2.4,mumathrm{m},odot}$ ($10^{-3} operatorname{Mpc}^{-3}$ brighter than $L_star$) and a $2.4,mu$m luminosity density equivalent to $3.8times10^{8},L_{2.4,mumathrm{m},odot}operatorname{Mpc}^{-3}$. $ldots$
Local infrared (IR) luminosity functions (LFs) are necessary benchmarks for high-redshift IR galaxy evolution studies. Any accurate IR LF evolution studies require accordingly accurate local IR LFs. We present infrared galaxy LFs at redshifts redshif
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