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Applying Information Theory to Design Optimal Filters for Photometric Redshifts [article]

J. Bryce Kalmbach, Jacob T. VanderPlas, Andrew J. Connolly
2020 arXiv   pre-print
In this paper we apply ideas from information theory to create a method for the design of optimal filters for photometric redshift estimation.  ...  Finally, we describe how information theory can be applied to a range of optimization problems in astronomy.  ...  CONCLUSION We have introduced a new technique to apply information theory to the design of filters in order to optimize photometric redshifts.  ... 
arXiv:2001.01372v1 fatcat:agrv6bpifzajvlzu4l5bizab2a

An information-based metric for observing strategy optimization, demonstrated in the context of photometric redshifts with applications to cosmology [article]

Alex I. Malz, François Lanusse, John Franklin Crenshaw, Melissa L. Graham
2021 arXiv   pre-print
We propose a metric for observing strategy optimization based on the potentially recoverable mutual information about redshift from a photometric sample under the constraints of a realistic observing strategy  ...  We recommend the use of this versatile metric to observing strategy optimization for redshift-dependent extragalactic use cases, including but not limited to cosmology, as well as any other science applications  ...  It also demonstrates consistency with the results of Kalmbach et al. (2020) , who found that using information theory to optimize filters for photo-s corresponds to designing filters that can optimally  ... 
arXiv:2104.08229v1 fatcat:asvt27x7t5eevj4hvb4umtny2a

Large Synoptic Survey Telescope Galaxies Science Roadmap [article]

Brant E. Robertson, Manda Banerji, Michael C. Cooper, Roger Davies, Simon P. Driver, Annette M. N. Ferguson, Henry C. Ferguson, Eric Gawiser, Sugata Kaviraj, Johan H. Knapen, Chris Lintott, Jennifer Lotz, Jeffrey A. Newman, Dara J. Norman (+31 others)
2017 arXiv   pre-print
The LSST Galaxies Science Collaboration has identified a host of preparatory research tasks required to leverage fully the LSST dataset for extragalactic science beyond the study of dark energy.  ...  This Galaxies Science Roadmap provides a brief introduction to critical extragalactic science to be conducted ahead of LSST operations, and a detailed list of preparatory science tasks including the motivation  ...  In addition to providing useful information about main-survey photometric redshift quality, the Deep Drilling Fields will pose particular challenges for photometric redshift determination, as spectroscopy  ... 
arXiv:1708.01617v1 fatcat:ifuatq7vkzbnljp7uggfbc2k5i

Calibrating Photometric Redshifts of Luminous Red Galaxies [article]

Nikhil Padmanabhan, Tamas Budavari, David J. Schlegel, Terry Bridges, Jonathan Brinkmann, Russell Cannon, Andrew J. Connolly, Scott M. Croom, Istvan Csabai, Michael Drinkwater, Daniel J. Eisenstein, Paul C. Hewett, Jon Loveday, Robert C. Nichol (+9 others)
2004 arXiv   pre-print
The methods we develop are applicable to general photometric redshift surveys.  ...  We also parametrize the photometric redshift error distribution with a sum of Gaussians, and use this model to deconvolve the errors from the measured photometric redshift distribution to estimate the  ...  For the LRGs, we start with an elliptical template from Coleman et al. (1980) and apply the above algorithm to optimize it.  ... 
arXiv:astro-ph/0407594v1 fatcat:ptbolkv37vetdact7ovhbgq4du

Calibrating photometric redshifts of luminous red galaxies

N. Padmanabhan, T. Budavari, D. J. Schlegel, T. Bridges, J. Brinkmann, R. Cannon, A. J. Connolly, S. M. Croom, I. Csabai, M. Drinkwater, D. J. Eisenstein, P. C. Hewett (+11 others)
2005 Monthly notices of the Royal Astronomical Society  
For the LRGs, we start with an elliptical template from Coleman et al. (1980) and apply the above algorithm to optimize it.  ...  This single optimized template is used for an initial redshift estimate for all LRGs.  ... 
doi:10.1111/j.1365-2966.2005.08915.x fatcat:5u2ohpna4jd4dhz4juw5dvmtwm

The first and second data releases of the Kilo-Degree Survey

Jelte T. A. de Jong, Gijs A. Verdoes Kleijn, Danny R. Boxhoorn, Hugo Buddelmeijer, Massimo Capaccioli, Fedor Getman, Aniello Grado, Ewout Helmich, Zhuoyi Huang, Nancy Irisarri, Konrad Kuijken, Francesco La Barbera (+37 others)
2015 Astronomy and Astrophysics  
Designed for weak lensing shape and photometric redshift measurements, the core science driver of the survey is mapping the large-scale matter distribution in the Universe back to a redshift of ~0.5.  ...  Early scientific results include the detection of nine high-z QSOs, fifteen candidate strong gravitational lenses, high-quality photometric redshifts and galaxy structural parameters for hundreds of thousands  ...  Exposure times and observing constraints for the four filters are designed to match the atmospheric conditions on Paranal and optimized for the survey's main scientific goal of weak gravitational lensing  ... 
doi:10.1051/0004-6361/201526601 fatcat:zp2zeb3senc47f3nvbkxzpynu4

How Future Space-Based Weak-Lensing Surveys Might Obtain Photometric Redshifts Independently

R. Sorba, M. Sawicki
2011 Publications of the Astronomical Society of the Pacific  
We study how the addition of on-board optical photometric bands to future space-based weak lensing instruments could affect the photometric redshift estimation of galaxies, and hence improve estimations  ...  We find that adding two (U and G) or even one (U) on-board optical band-passes to the space-based infrared instrument greatly improves its photometric redshift performance, bringing it close to the level  ...  High-performance computing resources for this work were supplied by the Atlantic Computational Excellence Network (ACEnet).  ... 
doi:10.1086/660843 fatcat:vdm7s4tpevc3vigig3dlcrrehi

A Composite Likelihood Approach for Inference under Photometric Redshift Uncertainty [article]

M. M. Rau, C. B. Morrison, S. J. Schmidt, S. Wilson, R. Mandelbaum, Y. Y. Mao
2021 arXiv   pre-print
We evaluate and forecast photometric redshift performance using data from the CosmoDC2 simulations, within which we mimic a DESI-like spectroscopic calibration sample for cross-correlations.  ...  Obtaining accurately calibrated redshift distributions of photometric samples is one of the great challenges in photometric surveys like LSST, Euclid, HSC, KiDS, and DES.  ...  We would like to thank the internal reviewers David Alonso, Will Hartley and David Kirkby for their insightful  ... 
arXiv:2101.01184v1 fatcat:aezw4zhhnbeajmagmrbf4awi4e

The Whole is Greater than the Sum of the Parts: Optimizing the Joint Science Return from LSST, Euclid and WFIRST [article]

B. Jain, D. Spergel, R. Bean, A. Connolly, I. Dell'antonio, J. Frieman, E. Gawiser, N. Gehrels, L. Gladney, K. Heitmann, G. Helou, C. Hirata (+16 others)
2015 arXiv   pre-print
However, enabling the astronomy community to fully exploit this multi-instrument data set is a challenging technical task: for much of the science, we will need to combine the photometry across multiple  ...  The sum of these surveys has the potential to be significantly greater than the contributions of the individual parts.  ...  An ideal training set would span the full range of properties (including redshifts) of the galaxies to which photometric redshifts will be applied.  ... 
arXiv:1501.07897v2 fatcat:f6ftnvua2rdc3o5bx3ipoowake

J-PLUS: On the identification of new cluster members in the double galaxy cluster A2589 and A2593 using PDFs

A. Molino, M. V. Costa-Duarte, C. Mendes de Oliveira, A. J. Cenarro, G. B. Lima Neto, E. S. Cypriano
2018 Astronomy and Astrophysics  
We aim to use multi-band imaging from the Phase-3 Verification Data of the J-PLUS survey to derive accurate photometric redshifts (photo-z) and look for potential new members in the surroundings of the  ...  We present an optimized pipeline for the estimation of photo-z in clusters of galaxies.  ...  Paladini at IAG/USP for helping with software installation. We thanks the anonymous referee for the careful reading of this manuscript and for her/his constructive comments and suggestions.  ... 
doi:10.1051/0004-6361/201731348 fatcat:hbmhaw5wtja2tm4qishplfjah4

Photometric Redshifts for Cosmology: Improving Accuracy and Uncertainty Estimates Using Bayesian Neural Networks [article]

Evan Jones, Tuan Do, Bernie Boscoe, Yujie Wan, Zooey Nguyen, Jack Singal
2022 arXiv   pre-print
We turn to Bayesian neural networks (BNNs) as a promising way to provide accurate predictions of redshift values.  ...  We evaluate the performance and accuracy of photometric redshift (photo-z) predictions from photometry using machine learning, astronomical and probabilistic metrics.  ...  In a future work we will apply galaxy photometric images to a Bayesian convolutional neural network, which we believe will enhance the information present in the band fluxes.  ... 
arXiv:2202.07121v1 fatcat:b2ve2jq6ffb6ta3auwcc6hmici

Estimating Spectra from Photometry

J. Bryce Kalmbach, Andrew J. Connolly
2017 Astronomical Journal  
We are able to reduce the photometric redshifts standard deviation by at least 22.0 compared to original set for z ≤ 3.  ...  Finally, we demonstrate the usefulness of our technique by generating 50 additional SED templates from an original set of 10 and applying the new set to photometric redshift estimation.  ...  The authors would like to thank Chris Morrison and Scott Daniel for reading and providing comments on early drafts of this manuscript. This work was supported by the U.S.  ... 
doi:10.3847/1538-3881/aa9933 fatcat:wdpjlbc3k5dwng2kor56zvgjnm

SuperCLASS – II: Photometric Redshifts and Characteristics of Spatially-Resolved μJy Radio Sources [article]

Sinclaire M. Manning, Caitlin M. Casey, Chao-Ling Hung, Richard Battye, Michael L. Brown, Neal Jackson, Filipe Abdalla, Scott Chapman, Constantinos Demetroullas, Patrick Drew, Christopher A. Hales, Ian Harrison, Christopher J. Riseley, David B. Sanders (+1 others)
2020 arXiv   pre-print
We derive photometric redshifts for ≈176,000 sources down to i^'_ AB∼24 and present photometric redshifts for 1.4 GHz e-MERLIN and VLA detected radio sources found in the central 0.26 deg^2.  ...  We compile an initial catalog of 149 radio sources brighter than S_1.4>75μJy and find their photometric redshifts span 07 σ in the density map and we confirm the photometric redshifts are consistent with  ...  ACKNOWLEDGEMENTS The authors thank the reviewer, Kenneth Duncan, for his helpful comments and suggestions.  ... 
arXiv:2003.01735v1 fatcat:xigthg2mrzhbba7eru3c6xuly4

Data-driven, Interpretable Photometric Redshifts Trained on Heterogeneous and Unrepresentative Data

Boris Leistedt, David W. Hogg
2017 Astrophysical Journal  
Our model can also be used to predict missing photometric fluxes, or to simulate populations of galaxies with realistic fluxes and redshifts, for example.  ...  We present a new method for inferring photometric redshifts in deep galaxy and quasar surveys, based on a data driven model of latent spectral energy distributions (SEDs) and a physical model of photometric  ...  Figure 1 . 1 Photometric filters used for the data demonstration.  ... 
doi:10.3847/1538-4357/aa6332 fatcat:65qvfqhbkvgs5f5i55ucdp3urm

OUP accepted manuscript

2020 Monthly notices of the Royal Astronomical Society  
We derive photometric redshifts for ≈176,000 sources down to i AB ∼ 24 and present photometric redshifts for 1.4 GHz e-MERLIN and VLA detected radio sources found in the central 0.26 deg 2 .  ...  Using the full photometric redshift catalog we construct a density map at the redshift of the known galaxy clusters, z = 0.20 ± 0.08.  ...  ACKNOWLEDGEMENTS The authors thank the reviewer, Kenneth Duncan, for his helpful comments and suggestions.  ... 
doi:10.1093/mnras/staa657 fatcat:xts4ni3z7bhzhccxddy2ri6cae
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