Modeling the anomaly of surface number densities of galaxies on the Galactic extinction map due to their FIR emission contamination

Abstract

The most widely used Galactic extinction map (Schlegel, Finkbeiner, & Davis 1998, SFD) is constructed assuming that the observed FIR fluxes entirely come from the Galactic dust. According to the earlier suggestion by Yahata et al. (2007), we consider how far-infrared (FIR) emission of galaxies affects the SFD map. We first compute the surface number density of SDSS DR7 galaxies as a function of the $r$-band extinction, $A_{r,\mathrm{SFD}}$. We confirm that the surface densities of those galaxies positively correlate with $A_{r,\mathrm{SFD}}$ for $A_{r,\mathrm{SFD}}<0.1$, as first discovered by Yahata et al. (2007) for SDSS DR4 galaxies. Next we construct an analytic model to compute the surface density of galaxies taking account of the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of $100\mu \mathrm{m}$ and $r$-band luminosities of each galaxy, $y\equiv (\nu L{)}_{100\mu \mathrm{m}}/(\nu L{)}_r$. Then we search for the mean and r.m.s values of $y$ that fit the observed anomaly using the analytic model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies (Kashiwagi, Yahata, & Suto 2013). Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. While the corresponding systematic error in the Galactic extinction map is 0.1 to 1mmag, it is directly correlated with galaxy clustering, and thus needs to be carefully examined in precision cosmology.

arXiv comment20 pages, 12 figures, accepted for publication in ApJ

References in corpus (35)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The Sloan Digital Sky Survey: Technical Summary
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Seventh Data Release of the Sloan Digital Sky Survey
• Correcting for the Effects of Interstellar Extinction
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• The Sloan Digital Sky Survey Photometric Camera
• The u'g'r'i'z' Standard Star Network
• The Fourth Data Release of the Sloan Digital Sky Survey
• The First Data Release of the Sloan Digital Sky Survey
• Astrometric Calibration of the Sloan Digital Sky Survey
• The Infrared Astronomical Mission AKARI
• A photometricity and extinction monitor at the Apache Point Observatory
• The PSCz Catalogue
• SDSS Data Management and Photometric Quality Assessment
• The properties and luminosity function of extremely low luminosity galaxies
• The Sloan Digital Sky Survey Monitor Telescope Pipeline
• Analysis of Systematic Effects and Statistical Uncertainties in Angular Clustering of Galaxies from Early SDSS Data
• Galaxy Number Counts from the Sloan Digital Sky Survey Commissioning Data
• SDSSJ150634.27+013331.6: the second compact elliptical galaxy in the NGC5846 group
• The Blue Tip of the Stellar Locus: Measuring Reddening with the SDSS
• Measuring Galactic Extinction: A Test
• Modeling Nonlinear Evolution of Baryon Acoustic Oscillations: Convergence Regime of N-body Simulations and Analytic Models
• The Luminosity Function of IRAS PSCz Galaxies
• The Structure of Molecular Clouds: I - All Sky Near Infrared Extinction Maps
• Far-infrared dust opacity and visible extinction in the Polaris Flare
• A Correction to the Standard Galactic Reddening Map: Passive Galaxies as Standard Crayons
• An Extinction Study of the Taurus Dark Cloud Complex
• Large-scale variations of the dust optical properties in the Galaxy
• The local sub-mm luminosity functions and predictions from Spitzer to Herschel
• The effect of FIR emission from SDSS galaxies on the SFD Galactic extinction map
• Spatial Variations of Galaxy Number Counts in the Sloan Digital Sky Survey. II. Test of Galactic Extinction in High Extinction Regions
• Spatial Variations of Galaxy Number Counts in the SDSS I.: Extinction, Large-Scale Structure and Photometric Homogeneity
• Detection of Far Infrared Emission from Galaxies and Quasars in the Galactic Extinction Map by Stacking Analysis

Cited by in corpus (2)

• Imaging Systematics and Clustering of DESI Main Targets
• Image Stacking Analysis of SDSS Galaxies with AKARI Far-Infrared Surveyor Maps at 65μm, 90μm, and 140μm