scholarly journals Spectroscopic Target Selection for the Sloan Digital Sky Survey: The Luminous Red Galaxy Sample

2001 ◽  
Vol 122 (5) ◽  
pp. 2267-2280 ◽  
Author(s):  
Daniel J. Eisenstein ◽  
James Annis ◽  
James E. Gunn ◽  
Alexander S. Szalay ◽  
Andrew J. Connolly ◽  
...  
Keyword(s):  
Target Selection ◽  
Sloan Digital Sky Survey ◽  
Sky Survey ◽  
Galaxy Sample ◽  
Selection For

scholarly journals Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Main Galaxy Sample

2002 ◽  
Vol 124 (3) ◽  
pp. 1810-1824 ◽  
Author(s):  
Michael A. Strauss ◽  
David H. Weinberg ◽  
Robert H. Lupton ◽  
Vijay K. Narayanan ◽  
James Annis ◽  
...  
Keyword(s):  
Target Selection ◽  
Sloan Digital Sky Survey ◽  
Main Galaxy ◽  
Sky Survey ◽  
Galaxy Sample

scholarly journals Producing a BOSS CMASS sample with DES imaging

2019 ◽  
Vol 489 (2) ◽  
pp. 2887-2906 ◽  
Author(s):  
S Lee ◽  
E M Huff ◽  
A J Ross ◽  
A Choi ◽  
C Hirata ◽  
...  
Keyword(s):  
Sloan Digital Sky Survey ◽  
Joint Analysis ◽  
Dark Energy Survey ◽  
Sky Survey ◽  
Angular Correlation Function ◽  
Galaxy Sample ◽  
Celestial Equator ◽  
The Difference ◽  
Galaxy Bias ◽  
Validation Tests

ABSTRACT We present a sample of galaxies with the Dark Energy Survey (DES) photometry that replicates the properties of the BOSS CMASS sample. The CMASS galaxy sample has been well characterized by the Sloan Digital Sky Survey (SDSS) collaboration and was used to obtain the most powerful redshift-space galaxy clustering measurements to date. A joint analysis of redshift-space distortions (such as those probed by CMASS from SDSS) and a galaxy–galaxy lensing measurement for an equivalent sample from DES can provide powerful cosmological constraints. Unfortunately, the DES and SDSS-BOSS footprints have only minimal overlap, primarily on the celestial equator near the SDSS Stripe 82 region. Using this overlap, we build a robust Bayesian model to select CMASS-like galaxies in the remainder of the DES footprint. The newly defined DES-CMASS (DMASS) sample consists of 117 293 effective galaxies covering $1244\,\deg ^2$. Through various validation tests, we show that the DMASS sample selected by this model matches well with the BOSS CMASS sample, specifically in the South Galactic cap (SGC) region that includes Stripe 82. Combining measurements of the angular correlation function and the clustering-z distribution of DMASS, we constrain the difference in mean galaxy bias and mean redshift between the BOSS CMASS and DMASS samples to be $\Delta b = 0.010^{+0.045}_{-0.052}$ and $\Delta z = \left(3.46^{+5.48}_{-5.55} \right) \times 10^{-3}$ for the SGC portion of CMASS, and $\Delta b = 0.044^{+0.044}_{-0.043}$ and $\Delta z= (3.51^{+4.93}_{-5.91}) \times 10^{-3}$ for the full CMASS sample. These values indicate that the mean bias of galaxies and mean redshift in the DMASS sample are consistent with both CMASS samples within 1σ.

scholarly journals Distribution of Maximal Luminosity of Galaxies in the Sloan Digital Sky Survey

2014 ◽  
Vol 10 (S306) ◽  
pp. 351-354
Author(s):  
E. Regős ◽  
A. Szalay ◽  
Z. Rácz ◽  
M. Taghizadeh ◽  
K. Ozogany
Keyword(s):  
Limit Distribution ◽  
Finite Size ◽  
Gumbel Distribution ◽  
Sloan Digital Sky Survey ◽  
Extreme Value Statistics ◽  
Independent Variables ◽  
Sky Survey ◽  
The Press ◽  
Galaxy Sample ◽  
Good Agreement

AbstractExtreme value statistics (EVS) is applied to the pixelized distribution of galaxy luminosities in the Sloan Digital Sky Survey (SDSS). We analyze the DR8 Main Galaxy Sample (MGS) as well as the Luminous Red Galaxy Sample (LRGS). A non-parametric comparison of the EVS of the luminosities with the Fisher-Tippett-Gumbel distribution (limit distribution for independent variables distributed by the Press-Schechter law) indicates a good agreement provided uncertainties arising both from the finite size of the samples and from the sample size distribution are accounted for. This effectively rules out the possibility of having a finite maximum cutoff luminosity.

Further Investigation of the Effect of Galaxy Interactions on Star Formation

2013 ◽  
Vol 22 (2) ◽  
Author(s):  
Xin-Fa Deng ◽  
Fuyang Zhang
Keyword(s):  
Star Formation ◽  
Survey Data ◽  
Control Sample ◽  
Sloan Digital Sky Survey ◽  
Apparent Magnitude ◽  
Galaxy Interactions ◽  
Main Galaxy ◽  
Sky Survey ◽  
Data Release ◽  
Galaxy Sample

AbstractFrom the apparent magnitude-limited the Main galaxy sample of the Sloan Digital Sky Survey Data Release 7, we construct a paired galaxy sample and a control sample without close companions with the projected separations

scholarly journals GALAXY CLUSTERING TOPOLOGY IN THE SLOAN DIGITAL SKY SURVEY MAIN GALAXY SAMPLE: A TEST FOR GALAXY FORMATION MODELS

2010 ◽  
Vol 190 (1) ◽  
pp. 181-202 ◽  
Author(s):  
Yun-Young Choi ◽  
Changbom Park ◽  
Juhan Kim ◽  
J. Richard Gott ◽  
David H. Weinberg ◽  
...  
Keyword(s):  
Galaxy Formation ◽  
Sloan Digital Sky Survey ◽  
Galaxy Clustering ◽  
Main Galaxy ◽  
Sky Survey ◽  
Galaxy Sample

scholarly journals Revealing galactic scale bars with the help of Galaxy Zoo

2012 ◽  
Vol 10 (H16) ◽  
pp. 324-324
Author(s):  
Karen L. Masters ◽  
Keyword(s):  
Stellar Mass ◽  
Sloan Digital Sky Survey ◽  
Gas Content ◽  
Barred Galaxies ◽  
Sky Survey ◽  
The Galaxy ◽  
Galaxy Sample ◽  
External Sources ◽  
Disc Galaxies ◽  
Environmental Dependence

AbstractWe use visual classifications of the brightest 250,000 galaxies in the Sloan Digital Sky Survey Main Galaxy Sample provided by citizen scientists via the Galaxy Zoo project (www.galaxyzoo.org, Lintott et al. 2008) to identify a sample of local disc galaxies with reliable bar identifications.These data, combined with information on the atomic gas content from the ALFALFA survey (Haynes et al. 2011) show that disc galaxies with higher gas content have lower bar fractions.We use a gas deficiency parameter to show that disc galaxies with more/less gas than expected for their stellar mass are less/more likely to host bars. Furthermore, we see that at a fixed gas content there is no residual correlation between bar fraction and stellar mass. We argue that this suggests previously observed correlations between galaxy colour/stellar mass and (strong) bar fraction (e.g. from the sample in Masters et al. 2011, and also see Nair & Abraham 2010) could be driven by the interaction between bars and the gas content of the disc, since more massive, optically redder disc galaxies are observed to have lower gas contents.Furthermore we see evidence that at a fixed gas content the global colours of barred galaxies are redder than those of unbarred galaxies. We suggest that this could be due to the exchange of angular momentum beyond co-rotation which might stop a replenishment of gas from external sources, and act as a source of feedback to temporarily halt or reduce the star formation in the outer parts of barred discs.These results (published as Masters et al. 2012) combined with those of Skibba et al. (2012), who use the same sample to show a clear (but subtle and complicated) environmental dependence of the bar fraction in disc galaxies, suggest that bars are intimately linked to the evolution of disc galaxies.

scholarly journals Compact galaxies and the size–mass galaxy distribution from a colour-selected sample at 0.04 < z < 0.15 supplemented by ugrizYJHK photometric redshifts

2020 ◽  
Vol 500 (2) ◽  
pp. 1557-1574
Author(s):  
Ivan K Baldry ◽  
Tricia Sullivan ◽  
Raffaele Rani ◽  
Sebastian Turner
Keyword(s):  
Galaxy Evolution ◽  
High Redshift ◽  
Sample Selection ◽  
Distribution Functions ◽  
Sloan Digital Sky Survey ◽  
Photometric Redshifts ◽  
Galaxy Distribution ◽  
Sky Survey ◽  
Galaxy Sample ◽  
Compact Galaxies

ABSTRACT The size–mass galaxy distribution is a key diagnostic for galaxy evolution. Massive compact galaxies are potential surviving relics of a high-redshift phase of star formation. Some of these could be nearly unresolved in Sloan Digital Sky Survey (SDSS) imaging and thus not included in galaxy samples. To overcome this, a sample was selected from the combination of SDSS and UKIRT Infrared Deep Sky Survey (UKIDSS) photometry to r &lt; 17.8. This was done using colour–colour selection, and then by obtaining accurate photometric redshifts (photo-z) using scaled flux matching (SFM). Compared to spectroscopic redshifts (spec-z), SFM obtained a 1σ scatter of 0.0125 with only 0.3 per cent outliers (|Δln (1 + z)| &gt; 0.06). A sample of 163 186 galaxies was obtained with 0.04 &lt; z &lt; 0.15 over $2300\, {\rm deg}^2$ using a combination of spec-z and photo-z. Following Barro et al. log Σ1.5 = log M* − 1.5log r50, maj was used to define compactness. The spectroscopic completeness was 76 per cent for compact galaxies (log Σ1.5 &gt; 10.5) compared to 92 per cent for normal-sized galaxies. This difference is primarily attributed to SDSS ‘fibre collisions’ and not the completeness of the main galaxy sample selection. Using environmental overdensities, this confirms that compact quiescent galaxies are significantly more likely to be found in high-density environments compared to normal-sized galaxies. By comparison with a high-redshift sample from 3D-HST, log Σ1.5 distribution functions show significant evolution, with this being a compelling way to compare with simulations such as EAGLE. The number density of compact quiescent galaxies drops by a factor of about 30 from z ∼ 2 to log (n/Mpc−3) = − 5.3 ± 0.4 in the SDSS–UKIDSS sample. The uncertainty is dominated by the steep cut off in log Σ1.5, which is demonstrated conclusively using this complete sample.

scholarly journals Galaxy bias and σ8 from counts in cells from the SDSS main sample

2020 ◽  
Vol 498 (1) ◽  
pp. L125-L129 ◽  
Author(s):  
Andrew Repp ◽  
István Szapudi
Keyword(s):  
Dark Matter ◽  
Sloan Digital Sky Survey ◽  
Matter Distribution ◽  
Sky Survey ◽  
The Galaxy ◽  
Galaxy Sample ◽  
Dark Matter Distribution ◽  
Galaxy Bias ◽  
Previous Prescription ◽  
In Cells

ABSTRACT The counts-in-cells (CIC) galaxy probability distribution depends on both the dark matter clustering amplitude σ8 and the galaxy bias b. We present a theory for the CIC distribution based on a previous prescription of the underlying dark matter distribution and a linear volume transformation to redshift space. We show that, unlike the power spectrum, the CIC distribution breaks the degeneracy between σ8 and b on scales large enough that both bias and redshift distortions are still linear; thus, we obtain a simultaneous fit for both parameters. We first validate the technique on the Millennium Simulation and then apply it to the Sloan Digital Sky Survey main galaxy sample. We find σ8 = 0.92 ± .08 and $b = 1.39^{+.11}_{-.09}$ consistent with previous complementary results from redshift distortions and from Planck.

scholarly journals Baryon acoustic oscillations in the Sloan Digital Sky Survey Data Release 7 galaxy sample

2010 ◽  
Vol 401 (4) ◽  
pp. 2148-2168 ◽  
Author(s):  
Will J. Percival ◽  
Beth A. Reid ◽  
Daniel J. Eisenstein ◽  
Neta A. Bahcall ◽  
Tamas Budavari ◽  
...  
Keyword(s):  
Survey Data ◽  
Sloan Digital Sky Survey ◽  
Acoustic Oscillations ◽  
Sky Survey ◽  
Data Release ◽  
Galaxy Sample ◽  
Baryon Acoustic Oscillations

scholarly journals Photometric redshifts from SDSS images using a convolutional neural network

2018 ◽  
Vol 621 ◽  
pp. A26 ◽  
Author(s):  
Johanna Pasquet ◽  
E. Bertin ◽  
M. Treyer ◽  
S. Arnouts ◽  
D. Fouchez
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Signal To Noise Ratio ◽  
Distribution Functions ◽  
Sloan Digital Sky Survey ◽  
Photometric Redshifts ◽  
Photometric Redshift ◽  
Probability Distribution Functions ◽  
Sky Survey ◽  
Galaxy Sample

We developed a deep convolutional neural network (CNN), used as a classifier, to estimate photometric redshifts and associated probability distribution functions (PDF) for galaxies in the Main Galaxy Sample of the Sloan Digital Sky Survey at z <  0.4. Our method exploits all the information present in the images without any feature extraction. The input data consist of 64 × 64 pixel ugriz images centered on the spectroscopic targets, plus the galactic reddening value on the line-of-sight. For training sets of 100k objects or more (≥20% of the database), we reach a dispersion σMAD <  0.01, significantly lower than the current best one obtained from another machine learning technique on the same sample. The bias is lower than 10−4, independent of photometric redshift. The PDFs are shown to have very good predictive power. We also find that the CNN redshifts are unbiased with respect to galaxy inclination, and that σMAD decreases with the signal-to-noise ratio (S/N), achieving values below 0.007 for S/N >  100, as in the deep stacked region of Stripe 82. We argue that for most galaxies the precision is limited by the S/N of SDSS images rather than by the method. The success of this experiment at low redshift opens promising perspectives for upcoming surveys.

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