A5053457046- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Spectroscopy and Laser Applications
- Adaptive optics and wavefront sensing
- Superconducting and THz Device Technology
- Atmospheric Ozone and Climate
- History and Developments in Astronomy
- Semiconductor Lasers and Optical Devices
- Geophysics and Gravity Measurements
- Atmospheric and Environmental Gas Dynamics
- Advanced Thermodynamic Systems and Engines
- Scientific Computing and Data Management
- Neutrino Physics Research
- Calibration and Measurement Techniques
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
European Southern Observatory
2016-2025
University of Oxford
2018
Rutgers, The State University of New Jersey
2018
University of Louisville
2018
Leiden University
2018
International Centre for Radio Astronomy Research
2018
The University of Western Australia
2018
Australian National University
2015-2018
Netherlands Institute for Radio Astronomy
2018
University of Groningen
1995-2018
The HI Parkes All-Sky Survey (HIPASS) Catalogue forms the largest uniform catalogue of sources compiled to date, with 4,315 identified purely by their content. data comprise southern region declination <+2 deg HIPASS, first blind survey cover entire sky. RMS noise for this is 13 mJy/beam and velocity range -1,280 12,700 km/s. Data search, verification parametrization methods are discussed along a description measured quantities. Full made available astronomical community including positions,...
We present the HIPASS Bright Galaxy Catalog (BGC), which contains 1000 H I brightest galaxies in southern sky as obtained from Parkes All-Sky Survey (HIPASS). The selection of sources is based on their peak flux density (Speak ≳ 116 mJy) measured spatially integrated spectrum. derived masses range ∼107 to 4 × 1010 M⊙. While BGC (z < 0.03) complete Speak, only a subset ∼500 can be considered (F 25 Jy km s-1). total 158 new redshifts. These belong 91 for no optical or infrared counterparts...
Abstract We use the catalogue of 4315 extragalactic H i 21-cm emission-line detections from Parkes All Sky Survey (HIPASS) to calculate most accurate measurement mass function (HIMF) galaxies date. The completeness HIPASS sample is well characterized, which enables an calculation space densities. HIMF fitted with a Schechter parameters α = −1.37 ± 0.03 0.05, log (M*Hi/M⊙) 9.80 h−275, and θ* (6.0 0.8 0.6) × 10−3h375 Mpc−3 dex−1 (random systematic uncertainties at 68 per cent confidence...
Many results in modern astrophysics rest on the notion that Initial Mass Function (IMF) is universal. Our observations of HI selected galaxies light H-alpha and far-ultraviolet (FUV) challenge this notion. The flux ratio H-alpha/FUV from these two star formation tracers shows strong correlations with surface-brightness R band: Low Surface Brightness (LSB) have lower ratios compared to High expectations equilibrium models using commonly favored IMF parameters. Weaker but significant...
The H I mass function (HIMF) for galaxies in the local universe is constructed from results of Arecibo Strip Survey, a blind extragalactic survey 21 cm line. survey, consisting two strips covering total ~65 deg2 sky, with depth cz = 7400 km s-1, was optimized to detect column densities neutral gas NH > 1018 cm-2 (5 σ). yielded 66 significant signals, which approximately 50% are cataloged galaxies. No free-floating clouds without stars found. VLA follow-up observations all signals have been...
We introduce the Survey for Ionization in Neutral Gas Galaxies (SINGG), a census of star formation HI-selected galaxies. The survey consists H-alpha and R-band imaging sample 468 galaxies selected from HI Parkes All Sky (HIPASS). spans three decades mass is free many biases that affect other forming galaxy samples. present criteria selection, list entire sample, discuss our observational techniques, describe data reduction calibration methods. This paper focuses on 93 SINGG targets whose...
We present the largest catalogue to date of optical counterparts for HI radio-selected galaxies, Hopcat. Of 4315 radio-detected sources from Parkes All Sky Survey (Hipass) catalogue, we find 3618 (84%) galaxies. these, 1798 (42%) have confirmed velocities and 848 (20%) are single matches without velocities. Some galaxy members groups. From these multiple matches, 714 (16%) a further 258 (6%) galaxies For 481 (11%), but no counterpart can be chosen 216 (5%) obvious present. Most 'blank...
A comprehensive analysis of 355 high-quality Westerbork Synthesis Radio Telescope (WSRT) H i 21-cm line maps nearby galaxies shows that the properties and incident rate damped Lyman α absorption systems (DLAs) observed in spectra high-redshift QSOs are good agreement with DLAs originating gas discs like those z≈ 0 population. Comparison low-z DLA statistics incidence column density distribution f(NH i) for local galaxy sample no evidence evolution integral 'cross-section density'〈nσ〉=l−1 (l=...
We use the first data release from SINGG H-alpha survey of HI-selected galaxies to study quantitative behavior diffuse, warm ionized medium (WIM) across range properties represented by these 109 galaxies. The mean fraction f_WIM diffuse gas in this sample is 0.59+/- 0.19, slightly higher than found previous samples. Since lower surface-brightness tend have f_WIM, we believe that most difference due selection effects favoring large, optically-bright, nearby with high star-formation rates. As...
A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions tens milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up ~15 km. To develop and test this capability, a Long Baseline Campaign (LBC) was carried out from September late November 2014, culminating in end-to-end observations, calibrations, imaging selected Science Verification (SV) targets. This paper presents an overview campaign its main results,...
We present spatially resolved (∼50 pc) imaging of molecular gas species in the central kiloparsec nearby starburst galaxy NGC 253, based on observations taken with Atacama Large Millimeter/submillimeter Array. A total 50 lines are detected over a 13 GHz bandwidth imaged 3 mm band. Unambiguous identifications assigned for 27 lines. Based measured high CO/C17O isotopic line ratio (≳350), we show that 12CO(1–0) has moderate optical depths. comparison HCN and HCO+ their 13C-substituted...
We use ALMA to derive the mass, length, and time scales associated with nuclear starburst in NGC 253. This region forms ~2 M_sun/yr of stars resembles other starbursts scaling relations, star formation consuming gas reservoir 10 times faster than galaxy disks. present observations CO, high effective density transitions HCN(1-0), HCO+(1-0), CS(2-1), their isotopologues. identify ten clouds that appear as peaks line emission enhancements HCN-to-CO ratio. These are massive (~10^7 M_sun)...
We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) [CII] observations of the z=4.7555 submillimetre galaxy, ALESS 73.1. Our 0.5" FWHM map resolves emitting gas which is centred close to active galactic nucleus (AGN). The kinematics are dominated by rotation but with high turbulence, v_rot/sigma_int~3.1, and a Toomre Q parameter <1 throughout disk. By fitting three independent thin rotating disk models our data, we derive total dynamical mass 3+-2x10^10 M_sol....
We present initial results of very high resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations the z = 3.042 gravitationally lensed submillimeter galaxy HATLAS J090311.6+003906 (SDP.81). These were carried out using a extended configuration as part Science Verification for 2014 ALMA Long Baseline Campaign, with baselines up to ∼15 km. continuum imaging at 151, 236, and 290 GHz unprecedented angular resolutions fine 23 mas, corresponding an unmagnified spatial scale ∼180...
We present a new accurate measurement of the HI mass function galaxies from HIPASS Bright Galaxy Catalog, sample 1000 with highest peak flux densities in southern hemisphere (Koribalski et al. 2003). This spans nearly four orders magnitude (from log M_HI/M_sun=6.8 to 10.6, H0=75) and is largest selected date. develop bivariate maximum likelihood technique measure space density galaxies, show that this robust method, insensitive effects large scale structure. The resulting can be fitted...
PLANET (the Probing Lensing Anomalies NETwork) is a worldwide collaboration of astronomers whose primary goal to monitor microlensing events densely and precisely in order detect study anomalies that contain information about Galactic lenses sources would otherwise be unobtainable. The results PLANET's highly successful first year operation are presented here. Details the observational setup, observing procedures, data-reduction procedures used track progress real time at three participating...
We present the B-band Tully-Fisher relation for low surface brightness (LSB) galaxies. These LSB galaxies follow same as normal spiral This implies that mass-to-light ratio (M/L) of is typically a factor 2 larger than total luminosity and morphological type. Since dynamical mass galaxy related to rotational velocity scalelength via M∼V2h, at fixed linewidth must be twice large confirmed by examining between The universal nature can understood if are with density, sigma. density apparently...
The Northern HIPASS catalogue (NHICAT) is the northern extension of catalogue, HICAT (Meyer et al. 2004). This adds sky area between declination range +2 deg < dec. +25.5 to HICAT's -90 deg. a blind HI survey using Parkes Radio Telescope covering 71% (including this extension) and heliocentric velocity -1,280 km/s 12,700 . entire Virgo Cluster region has been observed in HIPASS. galaxy NHICAT, contains 1002 sources with v_hel > 300 Sources -300 were excluded avoid contamination by...
We measure the neutral atomic hydrogen (H i) gas content of field galaxies at intermediate redshifts z ∼ 0.1 and ∼0.2 using 21-cm emission lines observed with Westerbork Synthesis Radio Telescope. In order to make high signal-to-noise ratio detections, an H i signal stacking technique is applied: spectra from multiple galaxies, optically selected by second Canadian Network for Observational Cosmology redshift survey project, are co-added average mass in two bins. calculate cosmic densities...
We study the contribution of galaxies with different properties to global densities star formation rate (SFR), atomic (HI) and molecular hydrogen (H2) as a function redshift. use GALFORM model galaxy formation, which is set in LCDM framework. This includes self-consistent calculation SFR, depends on H2 content galaxies. The predicted SFR density how much this contributed by stellar masses infrared luminosities are agreement observations. predicts modest evolution HI at z<3, also be always...
We study the atomic (HI) and molecular hydrogen (H2) contents of early-type galaxies (ETGs) their gas sources using GALFORM model galaxy formation. This uses a self-consistent calculation star formation rate (SFR), which depends on H2 content galaxies. first present new analysis HIPASS ATLAS3D surveys, with special emphasis ETGs. The predicts HI ETGs in agreement observations from these surveys only if partial ram pressure stripping hot is included, showing that neutral `quenched' place...