R. C. Nichol
A5091770862- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Cosmology and Gravitation Theories
- Astrophysical Phenomena and Observations
- Scientific Research and Discoveries
- Remote Sensing in Agriculture
- Pulsars and Gravitational Waves Research
- Adaptive optics and wavefront sensing
- Astrophysics and Star Formation Studies
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- CCD and CMOS Imaging Sensors
- Spectroscopy and Chemometric Analyses
- Plant Water Relations and Carbon Dynamics
- Advanced Vision and Imaging
- Geophysics and Gravity Measurements
- Gaussian Processes and Bayesian Inference
- History and Developments in Astronomy
- Computational Physics and Python Applications
- Calibration and Measurement Techniques
- Astro and Planetary Science
University of Surrey
2022-2025
Ludwig-Maximilians-Universität München
2024
Lancaster University
2024
American Public University System
2024
Stanford University
2024
Oak Ridge National Laboratory
2024
University of Portsmouth
2015-2024
University College London
2020-2024
Centre National de la Recherche Scientifique
2024
Aix-Marseille Université
2024
The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed investigations of distribution luminous and nonluminous matter in universe: a photometrically astrometrically calibrated digital imaging survey π sr above about Galactic latitude 30° five broad optical bands depth g' ∼ 23 mag, spectroscopic approximately 106 brightest galaxies 105 quasars found photometric object catalog produced by survey. This paper summarizes observational parameters products SDSS serves as an...
We measure cosmological parameters using the three-dimensional power spectrum $P(k)$ from over 200 000 galaxies in Sloan Digital Sky Survey (SDSS) combination with Wilkinson Microwave Anisotropy Probe (WMAP) and other data. Our results are consistent a ``vanilla'' flat adiabatic cold dark matter model constant without tilt ${(n}_{s}=1),$ running tilt, tensor modes, or massive neutrinos. Adding SDSS information more than halves WMAP-only error bars on some parameters, tightening...
The Sloan Digital Sky Survey (SDSS) is an imaging and spectroscopic survey that will eventually cover approximately one-quarter of the celestial sphere collect spectra ≈106 galaxies, 100,000 quasars, 30,000 stars, serendipity targets. In 2001 June, SDSS released to general astronomical community its early data release, roughly 462 deg2 including almost 14 million detected objects 54,008 follow-up spectra. were collected in drift-scan mode five bandpasses (u, g, r, i, z); our 95% completeness...
We develop a new method to constrain the star formation histories, dust attenuation and stellar masses of galaxies. It is based on two absorption-line indices, 4000-Å break strength Balmer index HδA. Together, these indices allow us mean ages galaxies fractional mass formed in bursts over past few Gyr. A comparison with broad-band photometry then yields estimates mass. generate large library Monte Carlo realizations different including starbursts varying range metallicities. use this median...
Aims. We present cosmological constraints from a joint analysis of type Ia supernova (SN Ia) observations obtained by the SDSS-II and SNLS collaborations. The dataset includes several low-redshift samples (z< 0.1), all three seasons (0.05 <z< 0.4), years (0.2 1), it totals 740 spectroscopically confirmed supernovae with high-quality light curves.
We analyze the bivariate distribution, in color versus absolute magnitude (u-r vs. Mr), of a low-redshift sample galaxies from Sloan Digital Sky Survey (2400 deg2, 0.004 < z 0.08, -23.5 Mr -15.5). trace bimodality distribution luminous to faint by fitting double Gaussians functions separated bins. Color-magnitude (CM) relations are obtained for red and blue distributions (early- late-type, predominantly field, galaxies) without using any cut morphology. Instead, analysis is based on...
In order to understand the formation and subsequent evolution of galaxies one must first distinguish between two main morphological classes massive systems: spirals early-type systems. This paper introduces a project, Galaxy Zoo, which provides visual classifications for nearly million galaxies, extracted from Sloan Digital Sky Survey (SDSS). achievement was made possible by inviting general public visually inspect classify these via internet. The project has obtained more than 4 × 107...
We study the relations between stellar mass, star formation history, size and internal structure for a complete sample of 122 808 galaxies drawn from Sloan Digital Sky Survey. show that low-redshift divide into two distinct families at mass 3 × 1010 M⊙. Lower-mass have young populations, low surface densities concentrations typical discs. Their histories are more strongly correlated with density than mass. A significant fraction lowest-mass in our experienced recent starbursts. At given...
The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its Second Data Release. This data release consists of 3324 deg2 five-band (ugriz) imaging with photometry for over 88 million unique objects, 367,360 spectra galaxies, quasars, stars, calibrating blank sky patches selected 2627 this area, tables measured parameters from these data. reach a depth r ≈ 22.2 (95% completeness limit point sources) are photometrically astrometrically calibrated to 2% rms 100 mas per...
This paper describes the Fourth Data Release of Sloan Digital Sky Survey (SDSS), including all survey-quality data taken through 2004 June. The release includes five-band photometric for 180 million objects selected over 6670 deg2 and 673,280 spectra galaxies, quasars, stars from 4783 those imaging using standard SDSS target selection algorithms. These numbers represent a roughly 27% increment Third Release; previous releases are included in present release. also an additional 131,840...
We combine the constraints from recent Ly$\ensuremath{\alpha}$ forest analysis of Sloan Digital Sky Survey (SDSS) and SDSS galaxy bias with previous clustering, latest supernovae, 1st year WMAP cosmic microwave background anisotropies. find significant improvements on all cosmological parameters compared to constraints, which highlights importance combining other probes. Combining we for primordial slope ${n}_{s}=0.98\ifmmode\pm\else\textpm\fi{}0.02$. see no evidence running,...
The Galaxy And Mass Assembly (GAMA) survey has been operating since February 2008 on the 3.9-m Anglo-Australian Telescope using AAOmega fibre-fed spectrograph facility to acquire spectra with a resolution of R~1300 for 120,862 SDSS selected galaxies. target catalogue constitutes three contiguous equatorial regions centred at 9h (G09), 12h (G12) and 14.5h (G15) each 12 x 4 sq.deg limiting fluxes r < 19.4, 19.8, 19.4 mag respectively (and additional limits other wavelengths). Spectra reliable...
This overview paper describes the legacy prospect and discovery potential of Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from DES early data.DES is using a wide-field camera (DECam) on 4 m Blanco Telescope in Chile to image 5000 sq deg sky five filters (grizY).
We present an overview of a new integral field spectroscopic survey called MaNGA (Mapping Nearby Galaxies at Apache Point Observatory), one three core programs in the fourth-generation Sloan Digital Sky Survey (SDSS-IV) that began on 2014 July 1. will investigate internal kinematic structure and composition gas stars unprecedented sample 10,000 nearby galaxies. summarize essential characteristics instrument design context MaNGA's key science goals prototype observations to demonstrate...
We analyse a z < 0.1 galaxy sample from the Sloan Digital Sky Survey focusing on variation in colour bimodality with stellar mass and projected neighbour density Σ, measurements of functions. The characteristic increases environmental about 1010.6 to (Kroupa initial function, H0= 70) for Σ range 0.1–10 Mpc−2. population naturally divides into red blue sequence locus sequences colour–mass colour–concentration indices not varying strongly environment. fraction galaxies is determined bins 0.2...
We introduce a method to constrain general cosmological models using Baryon Acoustic Oscillation (BAO) distance measurements from galaxy samples covering different redshift ranges, and apply this analyse drawn the Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift (2dFGRS). BAOs are detected in clustering of combined 2dFGRS SDSS main samples, measure distance–redshift relation at z= 0.2. luminous red galaxies 0.35. The observed scales calculated these sample jointly analysed estimates...
We present in this paper a detailed analysis of the effect environment on star formation activity galaxies within Early Data Release (EDR) Sloan Digital Sky Survey (SDSS). have used Hα emission line to derive rate (SFR) for each galaxy volume-limited sample 8598 with 0.05 ≤ z 0.095 and M(r*) -20.45. find that SFR is strongly correlated local (projected) density, thus we here density-SFR relation analogous density-morphology relation. The density seen three ways. First, overall distribution...
This paper describes the Third Data Release of Sloan Digital Sky Survey (SDSS). release, containing data taken up through 2003 June, includes imaging in five bands over 5282 deg2, photometric and astrometric catalogs 141 million objects detected these data, spectra 528,640 selected 4188 deg2. The pipelines analyzing both images spectroscopy are unchanged from those used our Second Release.
This paper describes the Fifth Data Release (DR5) of Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and represents completion SDSS-I project (whose successor, SDSS-II will continue mid-2008). It five-band photometric for 217 million objects selected over 8000 square degrees, 1,048,960 spectra galaxies, quasars, stars from 5713 degrees that imaging data. These numbers represent a roughly 20% increment those Fourth Release; previous releases are...
Morphology is a powerful indicator of galaxy’s dynamical and merger history. It strongly correlated with many physical parameters, including mass, star formation history the distribution mass. The Galaxy Zoo project collected simple morphological classifications nearly 900 000 galaxies drawn from Sloan Digital Sky Survey, contributed by hundreds thousands volunteers. This large number allows us to exclude classifier error, measure influence subtle biases inherent in classification. paper...
We present measurements of the Hubble diagram for 103 Type Ia supernovae (SNe) with redshifts 0.04 < z 0.42, discovered during first season (Fall 2005) Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. These data fill in redshift "desert" between low- and high-redshift SN surveys. combine SDSS-II new distance estimates published from ESSENCE survey, Legacy Survey, Space Telescope, a compilation nearby measurements. Combining Baryon Acoustic Oscillations SDSS Luminous Red Galaxy sample...
We analyze the u - r color distribution of 24,346 galaxies with Mr ≤ -18 and z < 0.08, drawn from Sloan Digital Sky Survey first data release, as a function luminosity environment. The is well fitted two Gaussian distributions, which we use to divide sample into blue red population. At fixed luminosity, mean (red) nearly independent environment, weakly significant (~3 σ) detection trend for colors become redder by 0.1-0.14 (0.03-0.06) mag factor ~100 increase in local density, characterized...