D. N. A. Murphy
A5082019015- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Nuclear Physics and Applications
- Scientific Research and Discoveries
- Astrophysical Phenomena and Observations
- Remote Sensing in Agriculture
- Astro and Planetary Science
- Particle Detector Development and Performance
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Carbon Dioxide Capture Technologies
- Medical Imaging Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Solar and Space Plasma Dynamics
- Hydrocarbon exploration and reservoir analysis
- Atmospheric and Environmental Gas Dynamics
- SAS software applications and methods
University of Cambridge
2016-2024
Pontificia Universidad Católica de Chile
2014-2024
University of Central Lancashire
2023
Rutherford Appleton Laboratory
2018-2020
Isaac Newton Group
2020
University of the Free State
2017
South African Radio Astronomy Observatory
2017
University College Dublin
2017
National College of Ireland
2015
Istituto Nazionale di Fisica Nucleare, Sezione di Milano
2015
Pan-STARRS1 has carried out a set of distinct synoptic imaging sky surveys including the $3π$ Steradian Survey and Medium Deep in 5 bands ($grizy_{P1}$). The mean 5$σ$ point source limiting sensitivities stacked 3$π$ $grizy_{P1}$ are (23.3, 23.2, 23.1, 22.3, 21.4) respectively. upper bound on systematic uncertainty photometric calibration across is 7-12 millimag depending bandpass. astrometric using Gaia frame comes from comparison results with Gaia: standard deviation median residuals ($...
WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for William Herschel Telescope, will see first light in late 2022. WEAVE comprises a 2-degree field-of-view prime-focus corrector system, nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and single large IFU. These systems feed dual-beam spectrograph covering wavelength range 366$-$959\,nm at $R\sim5000$, or two shorter ranges $R\sim20\,000$. After summarising...
We present the spectroscopic confirmation of a z = 2.45 protocluster. Its member galaxies lie within radius 1.4 Mpc (physical) on sky and along line sight. estimate an overdensity 10, suggesting that structure has made turnaround but is not assembled yet. A comparison to Millennium simulation suggests analogous structures evolve into 1014–1015 M⊙ h−1 type dark matter halos by 0, qualifying notion "protocluster." The search for complete census mock progenitor at these massive 0 clusters...
We present the Final Design of WEAVE next-generation spectroscopy facility for William Herschel Telescope (WHT), together with a status update on details manufacturing, integration and overall project schedule now that all major fabrication contracts are in place. also summary current planning behind 5-year initial phase survey operations. will provide optical ground-based follow up (LOFAR) space-based (Gaia) surveys. is multi-object multi-IFU utilizing new 2-degree prime focus field view at...
The Gaia -ESO Survey is a public spectroscopic survey that targeted ≳10 5 stars covering all major components of the Milky Way from end 2011 to 2018, delivering its final release in May 2022. Unlike other surveys, only observed across spectral types with dedicated, specialised analyses: O ( T eff ~ 30 000–52 000 K) way K-M (≳3500 K). physics throughout these stellar regimes varies significantly, which has previously prohibited any detailed comparisons between significantly different types....
Recently, Carnall et al. discovered two bright high redshift quasars using the combination of VST ATLAS and WISE surveys. The technique involved 3-D colour plane i-z:z-W1:W1-W2 with W1 (3.4 micron) W2 (4.5 bands taking place usual NIR J band to help decrease stellar dwarf contamination. Here we report on our continued search for 5.7<z<6.4 over an ~2x larger area ~3577 sq. deg. Southern Hemisphere. We have found further z>6 quasars, VST-ATLAS J158.6938-14.4211 at z=6.07 J332.8017-32.1036...
The INT Galactic Plane Survey (IGAPS) is the merger of optical photometric surveys, IPHAS and UVEX, based on data from Isaac Newton Telescope (INT) obtained between 2003 2018. Here, we present IGAPS point source catalogue. It contains 295.4 million rows providing photometry in filters, i, r, narrow-band Halpha, g U_RGO. footprint fills coordinate range, |b| < 5deg 30deg l 215deg. A uniform calibration, referred to Pan-STARRS system, applied g, r while Halpha calibration linked then...
We present a catalogue of 4098 photometrically selected galaxy clusters with median redshift <z> = 0.32 in the 270 square degree 'Stripe 82' region Sloan Digital Sky Survey (SDSS), covering celestial equator Southern Galactic Cap (-50 < RA 59 deg, |Dec| 1.25 deg). Owing to multi-epoch SDSS coverage this region, ugriz photometry is ~2 magnitudes deeper than single scans within main footprint. exploit detect galaxies using an algorithm that searches for statistically significant overdensities...
Aims. Construction of a new quasar candidate catalog from the Red-Sequence Cluster Survey 2 (RCS-2), identified solely photometric information using an automated algorithm suitable for large surveys. The performance is tested well-defined SDSS spectroscopic sample quasars and stars. Methods. Random Forest constructs RCS-2 point sources spectroscopically-confirmed stars quasars. identifies putative broadband magnitudes (g, r, i, z) colours. Exploiting NUV GALEX measurements subset objects, we...
We present an update on the overall construction progress of WEAVE next-generation spectroscopy facility for William Herschel Telescope (WHT), now that all major fabrication contracts are in place. also a summary current planning behind 5-year initial phase survey operations, and some detailed end-to-end science simulations have been effected to evaluate final on-sky performance after data processing. will provide optical ground-based follow up (LOFAR) space-based (Gaia) surveys. is...
The Gaia -ESO Survey is an European Southern Observatory (ESO) public spectroscopic survey that targeted 10 5 stars in the Milky Way covering major populations of disk, bulge and halo. observations were made using FLAMES on VLT obtaining both UVES high ( R ~ 47 000) GIRAFFE medium 20 resolution spectra. analysis spectra was work multiple teams (nodes) within five working groups (WG). homogenisation stellar parameters WG11 (high FGK stars) WG10 (medium described here. In cases, carried out a...
We present a new cluster detection algorithm designed for the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) survey but with generic application to any multiband data. The method makes no prior assumptions about properties of clusters other than (a) similarity in colour galaxies (the "red sequence") (b) an enhanced projected surface density. detector has three main steps: (i) it identifies members by photometrically filtering input catalogue isolate colour-magnitude space,...
We describe and apply a simple prescription for defining connected structures in galaxy redshift surveys. The method is based upon two passes with friends-of-friends groupfinder. first pass uses cylindrical linking volume to find groups clusters, order suppress the line-of-sight smearing introduced by large random velocities of galaxies within these deep potential wells. second pass, performed spherical volume, identifies components. This algorithm has been applied 2dFGRS, which it picks out...
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...
We report the detection of a significant excess in surface density far-infrared sources from Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) within ~1 Mpc centres 66 optically-selected clusters galaxies SDSS with <z>~0.25. From analysis multiwavelength properties their counterparts we conclude that emission is associated dust-obscured star formation and/or active galactic nuclei themselves. The reaches maximum at radius ~0.8 Mpc, where find 1.0\pm0.3 S_250um>34 mJy on average...
(Abridged) In tandem with observational datasets, we utilize realistic mock catalogs, based on a semi-analytic galaxy formation model, constructed specifically for Pan-STARRS1 Medium Deep Surveys in order to assess the performance of Probability Friends-of-Friends (PFOF, Liu et al.) group finder, and aim develop grouping optimization method applicable surveys like Pan-STARRS1. Producing PFOF catalogs under variety photometric redshift accuracies ({\sigma}{\Delta}z/(1+zs)), find that catalog...
We present an update on the overall integration progress of WEAVE next-generation spectroscopy facility for William Herschel Telescope (WHT), now scheduled first light in early-2021, with almost all components arrived at observatory. also a summary current planning behind 5-year initial phase survey operations, and some detailed end-to-end science simulations that have been implemented to evaluate final on-sky performance after data processing. will provide optical ground-based follow up...
ABSTRACT We exploit the VST ATLAS quasar (QSO) catalogue to perform three measurements of halo mass profile. First, we make a new estimate angular autocorrelation function ≈230 000 quasars with $z_{\rm photo}\lesssim 2.5$ and $17 &lt; g 22$. By comparing $\Lambda$CDM clustering correlation function, measure bias be $b_{\rm Q}\approx 2.1$, implying $M_{\rm halo} \approx 8.5\times 10^{11}\,h^{-1}\,{\rm M}_\odot$. Second, cross-correlate these $z\approx 1.7$ Planck cosmic microwave...
ABSTRACT We cross-correlate a low-contamination subset of the VST ATLAS $g\lt 22.5$ quasar catalogue with 21.5$ galaxy clusters, $r\lt 21$ galaxies and 19.5$ luminous red (LRGs) to probe their halo mass profiles via magnification bias caused by weak lensing. In case we find that at small scales are well fitted Navarro, Frenk, White models masses within expected range. For galaxies, consistency previous Sloan Digital Sky Survey-based results for galaxy–quasar cross-correlation...
The extensive stellar spectroscopic datasets that are available for studies in Galactic Archeaology thanks to, example, the Gaia-ESO Survey, now benefit from having a significant number of targets overlap with asteroseismology projects such as Kepler, K2 and CoRoT. Combining measurements spectroscopy allows us to attain greater accuracy regard parameters needed characterise populations Milky Way. aim this Survey special project is produce catalogue self-consistent by combining...
We present the VST ATLAS Quasar Survey, consisting of $\sim1,229,000$ quasar (QSO) candidates with $16<g<22.5$ over $\sim4700$ deg$^2$. The catalogue is based on ATLAS$+$NEOWISE imaging surveys and aims to reach a QSO sky density $130$ deg$^{-2}$ for $z<2.2$ $\sim30$ $z>2.2$. One this select targets 4MOST Cosmology Redshift Survey. To guide our selection, we use X-ray/UV/optical/MIR data in extended William Herschel Deep Field (WHDF) where find $g<22.5$ broad-line $269\pm67$ deg$^{-2}$,...
Radio galaxies are among the most massive in high redshift universe and known to often lie protocluster environments. We have studied fields of seven z = 2.2 radio with HAWK-I narrow-band broad-band imaging order map out their environment using Halpha emitters (HAEs). The results compared blank field HAE survey HiZELS. All galaxy overdense HAEs relative a typical HiZELS same area four richer than all except one 65 essentially random subfields size. star formation rates lower those necessary...
Context. The upcoming new generation of optical spectrographs on four-meter-class telescopes, with their huge multiplexing capabilities, excellent spectral resolution, and unprecedented wavelength coverage, will provide invaluable information for reconstructing the history star formation in individual galaxies up to redshifts about 0.7. Aims. We aim at defining simple but robust meaningful physical parameters that can be used trace coexistence widely diverse stellar components: younger...