D. J. B. Smith
A5058337612- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Global Peace and Security Dynamics
- Superconducting and THz Device Technology
- Remote Sensing in Agriculture
- Military and Defense Studies
- CCD and CMOS Imaging Sensors
- International Development and Aid
- Defense, Military, and Policy Studies
- Scientific Research and Discoveries
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Remote Sensing and LiDAR Applications
- History and Developments in Astronomy
- Cosmology and Gravitation Theories
- Peacebuilding and International Security
University of Hertfordshire
2016-2025
University College of the North
2022-2024
Agriculture and Food
2023
University of Arizona
2023
The University of Queensland
2023
Open Targets
2022
Action Network
2022
Deutsche Gesellschaft für Internationale Zusammenarbeit
2022
Global Environment Facility
2022
RTX (United States)
2022
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...
The LOFAR Two-metre Sky Survey (LoTSS) is a deep 120-168 MHz imaging survey that will eventually cover the entire Northern sky. Each of 3170 pointings be observed for 8 hrs, which, at most declinations, sufficient to produce ~5arcsec resolution images with sensitivity ~0.1mJy/beam and accomplish main scientific aims which are explore formation evolution massive black holes, galaxies, clusters galaxies large-scale structure. Due compact core long baselines LOFAR, provide excellent both highly...
The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168MHz survey of the entire northern sky for which observations are now 20% complete. We present our first full-quality public data release. For this release 424 square degrees, or 2% eventual coverage, in region HETDEX Spring Field (right ascension 10h45m00s to 15h30m00s and declination 45$^\circ$00$'$00$''$ 57$^\circ$00$'$00$''$) were mapped using a fully automated direction-dependent calibration imaging...
The Herschel ATLAS is the largest open-time key project that will be carried out on Space Observatory. It survey 510 square degrees of extragalactic sky, four times larger than all other surveys combined, in five far-infrared and submillimetre bands. We describe survey, complementary multi-wavelength datasets combined with data, six major science programmes we are undertaking. Using new models based a previous galaxies, present predictions properties sources wavebands.
Gravitational lensing is a powerful astrophysical and cosmological probe particularly valuable at submillimeter wavelengths for the study of statistical individual properties dusty starforming galaxies. However identification gravitational lenses often time-intensive, involving sifting large volumes imaging or spectroscopic data to find few candidates. We used early from Herschel Astrophysical Terahertz Large Area Survey demonstrate that wide-area surveys can simply easily detect strong...
In this paper we describe the first data release of Visible and Infrared Survey Telescope for Astronomy (VISTA) Deep Extragalactic Observations (VIDEO) survey. VIDEO is a ~12degree^2 survey in near-infrared Z,Y,J,H K_s bands, specifically designed to enable evolution galaxies large structures be traced as function both epoch environment from present day out z=4, active galactic nuclei (AGN) most massive up into reionization. With its depth area, will able fully explore period Universe where...
In this data release from the LOFAR Two-metre Sky Survey (LoTSS) we present 120-168MHz images covering 27% of northern sky. Our coverage is split into two regions centred at approximately 12h45m +44$^\circ$30' and 1h00m +28$^\circ$00' spanning 4178 1457 square degrees respectively. The were derived 3,451hrs (7.6PB) High Band Antenna which corrected for direction-independent instrumental properties as well direction-dependent ionospheric distortions during extensive, but fully automated,...
We present a catalogue of nearly 3,000 submillimetre sources detected at 850um over ~5 square degrees surveyed as part the James Clerk Maxwell Telescope (JCMT) SCUBA-2 Cosmology Legacy Survey (S2CLS). This is largest survey its kind 850um, probing meaningful cosmic volume peak star formation activity and increasing sample size galaxies selected by an order magnitude. describe wide component S2CLS, which covers key extragalactic fields: UKIDSS-UDS, COSMOS, Akari-NEP, Extended Groth Strip,...
WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for William Herschel Telescope, will see first light in late 2022. WEAVE comprises a 2-degree field-of-view prime-focus corrector system, nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and single large IFU. These systems feed dual-beam spectrograph covering wavelength range 366$-$959\,nm at $R\sim5000$, or two shorter ranges $R\sim20\,000$. After summarising...
ABSTRACT Source classifications, stellar masses, and star-formation rates are presented for ≈80 000 radio sources from the first data release of Low Frequency Array Two-metre Sky Survey (LoTSS) Deep Fields, which represents widest deep survey ever undertaken. Using multi-wavelength spanning ultraviolet to far-infrared, spectral energy distribution (SED) fitting is carried out all LoTSS host galaxies using four different SED codes, two include modelling contributions an active galactic...
We report the discovery of an unusual object near spiral galaxy IC 2497, discovered by visual inspection Sloan Digital Sky Survey (SDSS) as part Galaxy Zoo project. The object, known Hanny's Voorwerp, is bright in SDSS g band due to unusually strong OIII 4959-5007 emission lines. present results first targeted observations optical, UV and X-ray, which show that contains highly ionized gas. Although line ratios are similar extended emission-line regions luminous AGN, source this ionization...
We present the first direct and unbiased measurement of evolution dust mass function galaxies over past 5 billion years cosmic history using data from Science Demonstration Phase Herschel-ATLAS. The sample consists selected at 250{\mu}m which have reliable counterparts SDSS z < 0.5, contains 1867 sources. Dust masses are calculated both a single temperature grey-body model for spectral energy distribution also with multiple components. either shows no trend redshift. Splitting into bins...
Exploiting the Herschel Astrophysical Terahertz Large Area Survey Science Demonstration Phase survey data, we have determined luminosity functions (LFs) at rest-frame wavelengths of 100 and 250 μm several redshifts z ≳ 1, for bright submillimeter galaxies with star formation rates (SFRs) M☉ yr−1. We find that evolution comoving LF is strong up to ≈ 2.5, slows down higher redshifts. From LFs information on halo masses inferred from clustering analysis, derived an average relation between SFR...
The First Data Release (DR1) of the UKIRT Infrared Deep Sky Survey (UKIDSS) took place on 2006 July 21. UKIDSS is a set five large near-infrared surveys, covering complementary range areas, depths, and Galactic latitudes. DR1 first release survey-quality data from includes 320 sq degs multicolour to (Vega) K=18, complete (depending survey) in three bands ZYJHK, together with 4 deep JK an average depth K=21. In addition similar quantity incomplete filter coverage. JHK, regions low extinction,...
We report ground-based follow-up observations of the exceptional source, ID141, one brightest sources detected so far in H-ATLAS cosmological survey. ID141 was observed using IRAM 30-meter telescope and Plateau de Bure interferometer (PdBI), Submillimeter Array (SMA) Atacama Pathfinder Experiment (APEX) submillimeter to measure dust continuum emission lines main isotope carbon monoxide ([C I] [C II]). The detection strong CO with PdBI confirms that is at high redshift (z=4.243 +/- 0.001)....
We present a pan-chromatic analysis of an unprecedented sample 1402 250 micron-selected galaxies at z < 0.5 (mean = 0.24) from the Herschel-ATLAS survey. complement our Herschel 100-500 micron data with UV-K-band photometry Galaxy And Mass Assembly (GAMA) survey and apply MAGPHYS energy-balance technique to produce SEDs for representative selected spanning most recent 5 Gyr cosmic history. derive estimates physical parameters, including star formation rates, stellar masses, dust masses...
This paper presents a study of the local radio source population, by cross-comparing data from first release (DR1) LOFAR Two-Metre Sky Survey (LoTSS) with Sloan Digital (SDSS) DR7 main galaxy spectroscopic sample. The LoTSS DR1 provides deep (median rms noise 71 $\mathrm{\mu}$Jy at 150 MHz) over 424 square degrees sky, which is sufficient to detect 10615 (32 per cent) SDSS galaxies this sky area. An improved method separate active galactic nuclei (AGN) accurately sources emission powered...
We present Low-Frequency Array (LOFAR) High-Band observations of the Herschel-ATLAS North Galactic Pole survey area. The we have carried out, consisting four pointings covering around 142 deg2 sky in frequency range 126–173 MHz, does not provide uniform noise coverage but otherwise is representative quality data to be expected planned LOFAR wide-area surveys, and has been reduced using recently developed 'facet calibration' methods at a resolution approaching full sets (∼10 × 6 arcsec) an...
Radio emission is a key indicator of star formation activity in galaxies, but the radio luminosity–star relation has to date been studied almost exclusively at frequencies 1.4 GHz or above. At lower frequencies, effects thermal are greatly reduced, and so we would expect observed be completely dominated by synchrotron radiation from supernova-generated cosmic rays. As part LOFAR Surveys Key Science project, Herschel-ATLAS NGP field surveyed with an effective frequency 150 MHz. We select...
We report measurements of the carbon monoxide ground state rotational transition (12C16O J = 1--0) with Zpectrometer ultra-wideband spectrometer on 100-m diameter Green Bank Telescope. The sample comprises 11 galaxies redshifts between z 2.1 and 3.5 from a total 24 targets identified by Herschel-ATLAS photometric colors SPIRE instrument. Nine CO are new redshift determinations, substantially adding to number detections rest-frame peak submillimeter emission near 100um. confirm existence...
We constructed a sample of 23,344 radio-loud active galactic nuclei (RLAGN) from the catalogue derived LOFAR Two-Metre Sky Survey (LoTSS) survey HETDEX Spring field. Although separating AGN star-forming galaxies remains challenging, combination spectroscopic and photometric techniques we used gives us one largest available samples candidate RLAGN. sample, combined with recently developed analytical models, to investigate lifetime distribution show that large or giant powerful RLAGN are...
We present a study of the low-frequency radio properties star forming (SF) galaxies and active galactic nuclei (AGN) up to redshift $z=2.5$. The new spectral window probed by Low Frequency Array (LOFAR) allows us reconstruct continuum emission from 150 MHz 1.4 GHz an unprecedented depth for radio-selected sample $1542$ in $\sim 7~ \rm{deg}^2$ LOFAR Bo\"otes field. Using extensive multi-wavelength dataset available detailed modelling FIR UV energy distribution (SED), we are able separate...