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Extracting Stellar Population Parameters of Galaxies from Photometric Data Using Evolution Strategies and Locally Weighted Linear Regression [chapter]

Luis Alvarez, Olac Fuentes, Roberto Terlevich
2004 Lecture Notes in Computer Science  
We also test a hybrid algorithm combining Evolution Strategies and Locally Weighted Linear Regression (LWLR).  ...  Here we focus on the optimization of methods to obtain stellar population parameters (ages, proportions, redshift and reddening) from photometric data using evolutionary synthesis models.  ...  Conclusions We approached the problem of extracting stellar population parameters from photometric data as an optimization problem and we demonstrated that it can be solved with Evolution Strategies.  ... 
doi:10.1007/978-3-540-30134-9_53 fatcat:vhzjgrcvanfp3fyrszgyk565ga

CLEAR. I. Ages and Metallicities of Quiescent Galaxies at 1.0 < z < 1.8 Derived from Deep Hubble Space Telescope Grism Data

Vicente Estrada-Carpenter, Casey Papovich, Ivelina Momcheva, Gabriel Brammer, James Long, Ryan F. Quadri, Joanna Bridge, Mark Dickinson, Henry Ferguson, Steven Finkelstein, Mauro Giavalisco, Catherine M. Gosmeyer (+5 others)
2019 Astrophysical Journal  
We use deep Hubble Space Telescope spectroscopy to constrain the metallicities and (light-weighted) ages of massive ( M_∗/M_≳10) galaxies selected to have quiescent stellar populations at 1.068% of their  ...  stellar mass by a redshift of z>2.  ...  We apply this method to all of the galaxies in each of our redshift groups (z∼1.1, z∼1.2, z∼1.3, z∼1.6) to derive the probability density function parameters for each population. ORCID iDs  ... 
doi:10.3847/1538-4357/aaf22e fatcat:uj4slekrazchtizz4ggbyako6q

REQUIEM-2D: Spatially Resolved Stellar Populations from HST 2D Grism Spectroscopy [article]

Mohammad Akhshik, Katherine E. Whitaker, Gabriel Brammer, Guillaume Mahler, Keren Sharon, Joel Leja, Matthew B. Bayliss, Rachel Bezanson, Michael D. Gladders, Allison Man, Erica J. Nelson, Jane R. Rigby (+4 others)
2020 arXiv   pre-print
We test the accuracy of requiem2d using a simulated sample of massive galaxies at z 2 from the Illustris cosmological simulation and find we recover the general trends in SFH and median stellar ages.  ...  Our requiem2d code measures both unresolved and resolved stellar populations, ages, and star-formation histories (SFHs) for the ongoing REQIUEM (REsolving QUIEscent Magnified) Galaxies Survey, which targets  ...  ACKNOWLEDGEMENTS We would like to thank the anonymous referee for sharing valuable comments and questions that helped us improve the draft significantly.  ... 
arXiv:2008.02276v1 fatcat:u6zvlbqgirftvlzcwiaaroljuy

Computational Intelligence in Astronomy: A Survey

Ke Wang, Ping Guo, Fusheng Yu, Lingzi Duan, Yuping Wang, Hui Du
2018 International Journal of Computational Intelligence Systems  
knowledge from the data.  ...  With explosive growth of the astronomical data, astronomy has become a representative data-rich discipline so as to defy traditional research methodologies and paradigm to analyze data and discover new  ...  Acknowledgements This work was fully supported by grants from the National Natural Science Foundation of China  ... 
doi:10.2991/ijcis.11.1.43 fatcat:l6oo3e37tvdqjms5jmuoe2lrju

Galaxy populations in the 26 most massive galaxy clusters in the South Pole Telescope SPT-SZ survey

A. Zenteno, J. J. Mohr, S. Desai, B. Stalder, A. Saro, J. P. Dietrich, M. Bayliss, S. Bocquet, I. Chiu, A. H. Gonzalez, C. Gangkofner, N. Gupta (+4 others)
2016 Monthly notices of the Royal Astronomical Society  
Stacking the data in multiple redshift bins shows a hint of redshift evolution in the concentration when both the total population is used, and when only RS galaxies are used (at 2.1σ and 2.8σ, respectively  ...  We measure the galaxy radial profile, the luminosity function (LF), and the halo occupation number (HON) using optical data with a typical depth of m^* + 2.  ...  Other data come from the European Southern Observatory telescopes on La Silla and Paranal.  ... 
doi:10.1093/mnras/stw1649 fatcat:itrlokkbyvcxlomcwor5d6p6mq

Dependence of Type Ia supernova luminosities on their local environment

M. Roman, D. Hardin, M. Betoule, P. Astier, C. Balland, R. S. Ellis, S. Fabbro, J. Guy, I. Hook, D. A. Howell, C. Lidman, A. Mitra (+9 others)
2018 Astronomy and Astrophysics  
rest-frame colors; the latter are an indicator of the luminosity-weighted age of the stellar population in a galaxy.  ...  We measured low- and moderate-redshift host galaxy photometry in SNLS and SDSS images and used spectral energy distribution (SED) fitting techniques to derive host properties such as stellar mass and U-V  ...  This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute  ... 
doi:10.1051/0004-6361/201731425 fatcat:dkzxrnheajbjncj5wtzbaxqray

Mass-metallicity relation explored with CALIFA

S. F. Sánchez, F. F. Rosales-Ortega, B. Jungwiert, J. Iglesias-Páramo, J. M. Vílchez, R. A. Marino, C. J. Walcher, B. Husemann, D. Mast, A. Monreal-Ibero, R. Cid Fernandes, E. Pérez (+30 others)
2013 Astronomy and Astrophysics  
We present the results on the study of the global and local M-Z relation based on the first data available from the CALIFA survey (150 galaxies).  ...  In addition, we have computed the integrated and spatially resolved stellar masses (and surface densities), based on SDSS photometric data.  ...  This study makes uses of the data provided by the Calar Alto Legacy Integral Field Area (CALIFA) survey (http://califa. caha.es/). CALIFA is the first legacy survey being performed at Calar Alto.  ... 
doi:10.1051/0004-6361/201220669 fatcat:4jd6xsbrkfctzlevsk5bumleye

Fitting the integrated spectral energy distributions of galaxies

Jakob Walcher, Brent Groves, Tamás Budavári, Daniel Dale
2010 Astrophysics and Space Science  
We review here the field of SED fitting, describing the modelling of ultraviolet to infrared galaxy SEDs, the creation of multiwavelength data sets, and the methods used to fit model SEDs to observed galaxy  ...  We conclude that SED fitting can be used effectively to derive a range of physical properties of galaxies, such as redshift, stellar masses, star formation rates, dust masses, and metallicities, with care  ...  Spezzi for a careful reading of an early version of the manuscript. This research has made use of NASA's Astrophysics Data System Bibliographic Services.  ... 
doi:10.1007/s10509-010-0458-z fatcat:h7go2rphlrejfns74seur3hd3a

Stellar mass as a galaxy cluster mass proxy: application to the Dark Energy Survey redMaPPer clusters [article]

A. Palmese, J. Annis, J. Burgad, A. Farahi, M. Soares-Santos, B. Welch, M. da Silva Pereira, H. Lin, S. Bhargava, D. L. Hollowood, R. Wilkinson, P. Giles (+69 others)
2019 arXiv   pre-print
Stellar masses are computed using a Bayesian Model Averaging method, and are validated for DES data using simulations and COSMOS data.  ...  We introduce a galaxy cluster mass observable, μ_, based on the stellar masses of cluster members, and we present results for the Dark Energy Survey (DES) Year 1 observations.  ...  In our case, the set of parametersθ k define the stellar population properties (e.g. stellar mass, SFH parameters, metallicity) of model M k , and the data D are the galaxy's observed magnitudes.  ... 
arXiv:1903.08813v2 fatcat:qrflnhqpbfat7b6c3z7byzhgki

OUP accepted manuscript

2019 Monthly notices of the Royal Astronomical Society  
Secondly, we consider the connections between green-valley, post-starburst, and quiescent galaxies, using our inferred SFH shapes and the distributions of galaxy physical properties on the UVJ diagram.  ...  We present a Bayesian full-spectral-fitting analysis of 75 massive (M * > 10 10.3 M ) UVJselected galaxies at redshifts of 1.0 < z < 1.3, combining extremely deep rest-frame ultraviolet spectroscopy from  ...  evolution of its stellar population.  ... 
doi:10.1093/mnras/stz2544 fatcat:3gqedg4445he7ohn2irkyldal4

THE BLANCO COSMOLOGY SURVEY: DATA ACQUISITION, PROCESSING, CALIBRATION, QUALITY DIAGNOSTICS, AND DATA RELEASE

S. Desai, R. Armstrong, J. J. Mohr, D. R. Semler, J. Liu, E. Bertin, S. S. Allam, W. A. Barkhouse, G. Bazin, E. J. Buckley-Geer, M. C. Cooper, S. M. Hansen (+8 others)
2012 Astrophysical Journal  
The primary aim of the BCS survey is to provide the data required to optically confirm and measure photometric redshifts for Sunyaev-Zel'dovich effect selected galaxy clusters from the South Pole Telescope  ...  We calibrate our absolute photometry using the stellar locus in grizJ bands, and thus our absolute photometric scale derives from 2MASS which has ∼2 indicates a systematics floor in the relative stellar  ...  Third, there are morphological parameters that can be extracted after directly accounting for the local PSF, which allows for improvements in star-galaxy classification and the extraction of PSF corrected  ... 
doi:10.1088/0004-637x/757/1/83 fatcat:pyphsql6ifh45g3cwbdoycdtqa

The Grism Lens-amplified Survey from Space (Glass). IX. The Dual Origin of Low-mass Cluster Galaxies as Revealed by New Structural Analyses

Takahiro Morishita, Louis E. Abramson, Tommaso Treu, Benedetta Vulcani, Kasper B. Schmidt, Alan Dressler, Bianca M. Poggianti, Matthew A. Malkan, Xin Wang, Kuang-Han Huang, Michele Trenti, Maruša Bradač (+1 others)
2017 Astrophysical Journal  
Using deep Hubble Frontier Fields imaging and slitless spectroscopy from the Grism Lens-Amplified Survey from Space, we analyze 2200 cluster and 1748 field galaxies at 0.2≤ z≤0.7 to determine the impact  ...  Given the consistency of the small-r_e galaxies' stellar surface densities (and even colors) with those of systems more than ten times as massive, our findings suggest that clusters mark places where galaxy  ...  We do so by extrapolating a simple linear regression and show the results in Figure 11 .  ... 
doi:10.3847/1538-4357/835/2/254 fatcat:pm3b43lwtbf3vetfhy2swixlae

STELLAR LOCUS REGRESSION: ACCURATE COLOR CALIBRATION AND THE REAL-TIME DETERMINATION OF GALAXY CLUSTER PHOTOMETRIC REDSHIFTS

F. William High, Christopher W. Stubbs, Armin Rest, Brian Stalder, Peter Challis
2009 Astronomical Journal  
We present Stellar Locus Regression (SLR), a method of directly adjusting the instrumental broadband optical colors of stars to bring them into accord with a universal stellar color-color locus, producing  ...  We demonstrate that SLR-corrected colors are sufficiently accurate to allow photometric redshift estimates for galaxy clusters (using red sequence galaxies) with an uncertainty sigma_z/(1+z) = 0.6% per  ...  This publication has made use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California  ... 
doi:10.1088/0004-6256/138/1/110 fatcat:wu2xfxyhrbesfaryutfgakluzi

Clustering of red-sequence galaxies in the fourth data release ofthe Kilo-Degree Survey [article]

Mohammadjavad Vakili, Henk Hoekstra, Maciej Bilicki, Maria-Cristina Fortuna, Konrad Kuijken, Angus H. Wright, Marika Asgari, Michael Brown, Elisabeth Dombrovskij, Thomas Erben, Benjamin Giblin, Catherine Heymans (+4 others)
2020 arXiv   pre-print
After performing the selection, we mitigate the impact of survey properties on the observed number density of galaxies by assigning photometric weights to the galaxies.  ...  In this work, the red-sequence template is built using the broad-band optical+near infrared photometry of KiDS-VIKING and the overlapping spectroscopic data sets.  ...  This work has made use of python, including the packages numpy, scipy, pandas, and scikit-learn. Plots have been produced with matplotlib and seaborn.  ... 
arXiv:2008.13154v1 fatcat:saakyygdpzcgdhedjwyh5fkaiy

Determining the Dark Matter distribution in galaxies with Deep Learning [article]

Martín Emilio de los Rios, Mihael Petač, Bryan Zaldivar, Nina R. Bonaventura, Francesca Calore, Fabio Iocco
2021 arXiv   pre-print
The framework we have developed is capable of inferring the DM mass distribution within galaxies of mass 10^11-10^13M_⊙ with very high performance from the gravitationally baryon dominated internal regions  ...  We present a novel method to infer the Dark Matter (DM) content and spatial distribution within galaxies, based on convolutional neural networks trained within state-of-the-art hydrodynamical simulations  ...  Ricerca (MIUR), and Iniziativa Specifica TAsP of INFN.  ... 
arXiv:2111.08725v1 fatcat:rjft5sb37vgpbbpayb4gl57btm
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