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Related papers: Improving NASA/IPAC Extragalactic Database Redshif…

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Stereo estimation has made many advancements in recent years with the introduction of deep-learning. However the traditional supervised approach to deep-learning requires the creation of accurate and plentiful ground-truth data, which is…

Computer Vision and Pattern Recognition · Computer Science 2024-10-18 Dominik Hirner , Friedrich Fraundorfer

Photometric Redshift is critical for analyzing astronomical objects, but existing ML methods often overlook the aleatoric uncertainties inherent in observed data. We introduce Starkindler, a novel training objective that explicitly…

Instrumentation and Methods for Astrophysics · Physics 2025-12-30 Raahul Singh , Ashutosh Pandey

This paper summarizes the introductory presentation for a workshop that explored the challenges of making precision astronomical measurements using deeply depleted (thick) CCDs. While thick CCDs provide definite advantages in terms of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Christopher W. Stubbs

In this paper, we explore how the forthcoming generation of large-scale radio continuum surveys, with the inclusion of some degree of redshift information, can constrain cosmological parameters. By cross-matching these radio surveys with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Stefano Camera , Mário G. Santos , David J. Bacon , Matt J. Jarvis , Kim McAlpine , Ray P. Norris , Alvise Raccanelli , Huub Röttgering

We describe a new program for determining photometric redshifts, dubbed EAZY. The program is optimized for cases where spectroscopic redshifts are not available, or only available for a biased subset of the galaxies. The code combines…

Astrophysics · Physics 2009-11-13 Gabriel B. Brammer , Pieter G. van Dokkum , Paolo Coppi

The relation between redshift and the CMB temperature, $T_{CMB}(z)=T_0(1+z)$ is a key prediction of standard cosmology, but is violated in many non-standard models. Constraining possible deviations to this law is an effective way to test…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Avgoustidis , G. Luzzi , C. J. A. P. Martins , A. M. R. V. L. Monteiro

We calculate the systematic inhomogeneity-induced correction to the cosmological constant that one would infer from an analysis of the luminosities and redshifts of Type Ia supernovae, assuming a homogeneous universe. The calculation…

Astrophysics · Physics 2008-12-18 R. Ali Vanderveld , Eanna E. Flanagan , Ira Wasserman

When combining cosmological and oscillations results to constrain the neutrino sector, the question of the propagation of systematic uncertainties is often raised. We address this issue in the context of the derivation of an upper bound on…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-25 F. Couchot , S. Henrot-Versillé , O. Perdereau , S. Plaszczynski , B. Rouillé d'Orfeuil , M. Spinelli , M. Tristram

Hubble constant $H_0$ and weighted amplitude of matter fluctuations $S_8$ determinations are biased to higher and lower values, respectively, in the late Universe with respect to early Universe values inferred by the Planck collaboration…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-06 Shahnawaz A. Adil , Özgür Akarsu , Mohammad Malekjani , Eoin Ó Colgáin , Saeed Pourojaghi , Anjan A. Sen , M. M. Sheikh-Jabbari

Some functions entering cosmological analysis, such as the dark energy equation of state or systematic uncertainties, are unknown functions of redshift. To include them without assuming a particular form we derive an efficient method for…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Johan Samsing , Eric V. Linder

The low redshift structures of the Universe act as lenses in a similar way on the Cosmic Microwave Background light and on the distant galaxies (say at redshift about unity). As a consequence, the CMB temperature distortions are expected to…

Astrophysics · Physics 2009-10-31 L. Van Waerbeke , F. Bernardeau , K. Benabed

In the next years, several cosmological surveys will rely on imaging data to estimate the redshift of galaxies, using traditional filter systems with 4-5 optical broad bands; narrower filters improve the spectral resolution, but strongly…

We use measurements of luminosity-dependent galaxy bias at several different redshifts, SDSS at $z=0.05$, DEEP2 at $z=1$ and LBGs at $z=3.8$, combined with WMAP five-year cosmic microwave background anisotropy data and SDSS Red Luminous…

Astrophysics · Physics 2008-11-26 Francesco De Bernardis , Paolo Serra , Asantha Cooray , Alessandro Melchiorri

The Red-Sequence Cluster Survey (RCS) provides a large and deep photometric catalog of galaxies in the $z'$ and $R_c$ bands for ~90 square degrees of sky, and supplemental $V$ and $B$ data have been obtained for 33.6 deg$^{2}$. We compile a…

Astrophysics · Physics 2009-11-10 B. C. Hsieh , H. K. C. Yee , H. Lin , M. D. Gladders

Accurate photometric redshifts are calculated for nearly 200,000 galaxies to a 4.5 micron flux limit of ~13 uJy in the 8.5 deg^2 Spitzer/IRAC Shallow survey. Using a hybrid photometric redshift algorithm incorporating both neural-net and…

Cosmology and galaxy evolution studies with LSST, \Euclid, and {\it Roman}, will require accurate redshifts for the detected galaxies. In this study, we present improved photometric redshift estimates for galaxies using a template library…

Astrophysics of Galaxies · Physics 2020-08-06 Bomee Lee , Ranga-Ram Chary

The increasing precision of Cosmic Microwave Background (CMB) observations has unveiled significant tensions between different datasets, notably between Planck and the Atacama Cosmology Telescope (ACT), as well as with the late-Universe…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-02 Matteo Forconi , Eleonora DI Valentino

The CMB temperature-redshift relation, T_CMB(z)=T_0(1+z), is a key prediction of the standard cosmology, but is violated in many non standard models. Constraining possible deviations to this law is an effective way to test the LambdaCDM…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 G. Luzzi , R. T. Génova-Santos , C. J. A. P. Martins , M. De Petris , L. Lamagna

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

We present a novel approach to analyzing astronomical spectral survey data using our non-linear extension of an online dictionary learning algorithm. Current and upcoming surveys such as SPHEREx will use spectral data to build a 3D map of…

Instrumentation and Methods for Astrophysics · Physics 2023-11-28 Sean Bryan , Ayan Barekzai , Delondrae Carter , Philip Mauskopf , Julian Mena , Danielle Rivera , Abel S. Uriarte , Pao-Yu Wang
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