相关论文: A robust method for fitting peculiar velocity fiel…
We review the quantitative science that can be and has been done with redshift and peculiar velocity surveys of galaxies in the nearby universe. After a brief background setting the cosmological context for this work, the first part of this…
Robustness to outliers is a central issue in real-world machine learning applications. While replacing a model to a heavy-tailed one (e.g., from Gaussian to Student-t) is a standard approach for robustification, it can only be applied to…
IRAS flux densities, redshifts, and infrared luminosities are reported for all sources identified in the IRAS Revised Bright Galaxy Sample (RBGS), a complete flux-limited survey of all extragalactic objects with total 60 micron flux density…
We demonstrate here using both single-dish and interferometric observations that CO molecules are an excellent kinematic tracer, even in high-mass galaxies, allowing us to investigate for the first time the CO Tully-Fisher relation of…
The cosmological peculiar velocity field (deviations from the pure Hubble flow) of matter carries significant information on dark energy, dark matter and the underlying theory of gravity on large scales. Peculiar motions of galaxies…
We utilise the method of Wiener reconstruction with spherical harmonics and Bessel functions to recover the density and velocity fields from the IRAS 1.2Jy redshift survey. The results are robust to changes in prior parameters and the…
We describe a new method of overcoming problems inherent in peculiar velocity surveys by using data compression as a filter with which to separate large-scale, linear flows from small-scale noise that biases the results systematically. We…
This study is a part of the Cosmicflows-4 project with the aim of measuring the distances of more than ~10,000 spiral galaxies in the local universe up to ~15,000 km/s. New HI linewidth information has come primarily from the Arecibo Legacy…
We model the evolution of IR galaxies using a phenomenological approach to match the observed source counts at different IR wavelengths. We introduce a new algorithm for reproducing source counts based on direct integration of probability…
We analyse the Tully-Fisher relation at moderate redshift from the point of view of the underlying stellar populations, by comparing optical and NIR photometry with a phenomenological model that combines population synthesis with a simple…
All direct measurements of peculiar velocities of glaxies assume the Hubble law at low redshifts. However, it has been suggested by Segal et al (1993) that the correlation of redshifts and fluxes in a complete sample of IRAS galaxies is…
Our statistical studies comprise the mean relative velocity and velocity correlation for pairs of galaxies as a function of separation, and a bulk flow analysis determined on spheres of $10 h^{-1}$ $Mpc$ radius. In order to test the…
We introduce a simple linear equation relating the line-of-sight peculiar velocity and density contrast correlation functions. The relation, which we call the "Gaussian cell two-point energy-like equation", is valid in the…
Using the near infrared fluxes of local galaxies derived from COBE/DIRBE J(1.25 $\mu$m) K (2.2 $\mu$m) \& L (3.5 $\mu$m) band maps and published Cepheid distances, we construct Tully-Fisher (TF) diagrams for the nearby galaxies. The…
Weak gravitational lensing measurements based on photometry are limited by shape noise, the variance in the unknown unlensed orientations of the source galaxies. If the source is a disk galaxy with a well-ordered velocity field, however,…
Peculiar velocities introduce correlations between supernova magnitudes, which implies that the supernova Hubble diagram residual carries information on both the matter power spectrum at the present time and its growth rate. By a…
The Dark Energy Spectroscopic Instrument (DESI) Peculiar Velocity Survey aims to measure the peculiar velocities of early and late type galaxies within the DESI footprint using both the Fundamental Plane and optical Tully-Fisher relations.…
We present an I-band Tully-Fisher relation (TFR) for 18 nearby S0 galaxies using kinematics derived from long slit spectroscopy of stellar absorption lines. Our estimates of the circular velocity, V_c, at 2-3 exponential disk scale lengths…
The validity of estimation and smoothing parameter selection for the wide class of generalized additive models for location, scale and shape (GAMLSS) relies on the correct specification of a likelihood function. Deviations from such…
Accurate photometric redshift estimation is critical for observational cosmology, especially in large-scale surveys where spectroscopic measurements are impractical. Traditional approaches include template fitting and machine learning, each…