N. Metcalfe
A5054115522- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astrophysics and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Adaptive optics and wavefront sensing
- Pulsars and Gravitational Waves Research
- Scientific Research and Discoveries
- Radio Astronomy Observations and Technology
- Advanced Semiconductor Detectors and Materials
- CCD and CMOS Imaging Sensors
- Chalcogenide Semiconductor Thin Films
- History and Developments in Astronomy
- Impact of Light on Environment and Health
- Semiconductor Quantum Structures and Devices
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Distributed and Parallel Computing Systems
- Statistical and numerical algorithms
- Particle physics theoretical and experimental studies
Durham University
2015-2024
Space Telescope Science Institute
2015-2020
Centre National de la Recherche Scientifique
2019
Aix-Marseille Université
2019
Johns Hopkins University
2016
University of Hawaiʻi at Mānoa
2015
University of Hawaii System
2014
University of Hawaii at Hilo
2014
Trinity House
2013
IriSys (United States)
1999
We present optical light curves, redshifts, and classifications for 365 spectroscopically confirmed Type Ia supernovae (SNe Ia) discovered by the Pan-STARRS1 (PS1) Medium Deep Survey. detail improvements to PS1 SN photometry, astrometry calibration that reduce systematic uncertainties in distances. combine subset of 279 ($0.03 < z 0.68$) with useful distance estimates from SDSS, SNLS, various low-z HST samples form largest combined sample consisting a total 1048 ranging $0.01 2.3$, which we...
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 ($...
Results of the commissioning first Gemini Multi‐Object Spectrograph (GMOS) are described. GMOS and Gemini–North telescope act as a complete system to exploit large 8 m aperture with improved image quality. Key design features such on‐instrument wave‐front sensor (OIWFS) active flexure compensation maintain very high quality stability, allowing precision observations many targets simultaneously while reducing need for frequent recalibration reacquisition targets. In this paper, example in...
We present a three-dimensional map of interstellar dust reddening, covering three-quarters the sky out to distance several kiloparsecs, based on Pan-STARRS 1 (PS1) and 2MASS photometry. The reveals wealth detailed structure, from filaments large cloud complexes. has hybrid angular resolution, with most at an resolution –, maximum . distribution is determined in fully probabilistic framework, yielding uncertainty reddening along each line sight, as well stellar distances, reddenings,...
The SAMI Galaxy Survey will observe 3400 galaxies with the Sydney-AAO Multi-object Integral-field spectrograph (SAMI) on Anglo-Australian Telescope (AAT) in a 3-year survey which began 2013. We present throughput of system, science basis and specifications for target selection, observation plan combined properties selected galaxies. includes four volume limited galaxy samples based cuts proxy stellar mass, along low-stellar mass dwarf all from And Mass Assembly (GAMA) survey. GAMA regions...
We present a new 3D map of interstellar dust reddening, covering three quarters the sky (declinations δ ≳ −30°) out to distance several kiloparsecs. The is based on high-quality stellar photometry 800 million stars from Pan-STARRS 1 and 2MASS. divide into sightlines containing few hundred each, then infer distances types, along with line-of-sight distribution. Our incorporates more accurate average extinction law an additional 1.5 yr data, tracing greater extinctions at higher angular...
We report extensive observational data for five of the lowest redshift Super-Luminous Type Ic Supernovae (SL-SNe Ic) discovered to date, namely PTF10hgi, SN2011ke, PTF11rks, SN2011kf and SN2012il. Photometric imaging transients at +50 +230 days after peak combined with host galaxy subtraction reveals a luminous tail phase four these SL-SNe. A high resolution, optical near infrared spectrum from xshooter provides detection broad He I $\lambda$10830 emission line in (+50d) SN2012il, revealing...
In the past decade, several rapidly evolving transients have been discovered whose timescales and luminosities are not easily explained by traditional supernovae (SNe) models. The sample size of these objects has remained small due, at least in part, to challenges detecting short timescale with survey cadences. Here we present results from a search within Pan-STARRS1 Medium Deep Survey (PS1-MDS) for luminous transients. We identify 10 new time above half-maximum (t1/2) less than 12 days...
This paper describes the organization of database and catalog data products from Pan-STARRS1 $3\pi$ Steradian Survey. The are available in form an SQL-based relational MAST, Mikulski Archive for Space Telescopes at STScI. is described detail, including construction database, provenance data, schema, how tables related. Examples queries a range science goals included.
Abstract Quasars are galaxies hosting accreting supermassive black holes; due to their brightness, they unique probes of the early universe. To date, only a few quasars have been reported at <?CDATA $z\gt 6.5$?> (<800 Myr after big bang). In this work, we present six additional $z\gtrsim discovered using Pan-STARRS1 survey. We use sample 15 perform homogeneous and comprehensive analysis highest-redshift quasar population. report four main results: (1) majority show large blueshifts broad...
We present the details of photometric and astrometric calibration Pan-STARRS1 $3\pi$ Survey. The goals were to reduce systematic effects introduced by camera detectors, place all observations onto a system with consistent zero points over entire area surveyed, ~30,000 square degrees north $\delta$ = -30 degrees. compensates for similar so that positions, proper motions, parallaxes are reliable as well. Pan-STARRS Data Release 2 (DR2) astrometry is tied Gaia DR1 release.
We present griz light curves of 146 spectroscopically confirmed Type Ia Supernovae ($0.03 < z <0.65$) discovered during the first 1.5 years Pan-STARRS1 Medium Deep Survey. The natural photometric system is determined by a combination on-site measurements instrument response function and observations spectrophotometric standard stars. find that systematic uncertainties in are currently 1.2\% without accounting for uncertainty HST Calspec definition AB system. A Hubble diagram constructed with...
ABSTRACT The dust extinction curve is a critical component of many observational programs and an important diagnostic the physics interstellar medium. Here we present new measurements its variation toward tens thousands stars, hundred-fold larger sample than in existing detailed studies. We use data from APOGEE spectroscopic survey combination with ten-band photometry Pan-STARRS1, Two Micron All-Sky Survey, Wide-field Infrared Survey Explorer . find that optical through infrared well...
We have used Pan-STARRS1 to discover an extremely red late-L dwarf, which has (J-K)_MKO = 2.84 and (J-K)_2MASS 2.78, making it the reddest known field dwarf second only 2MASS J1207-39b among substellar companions. Near-IR spectroscopy shows a spectral type of L7 reveals triangular H-band continuum weak alkali (K I Na I) lines, hallmarks low surface gravity. astrometry from Hawaii Infrared Parallax Program gives distance 24.6+/-1.4 pc indicates much fainter J-band absolute magnitude than L...
We present the discovery of three new Milky Way satellites from our search for compact stellar overdensities in photometric catalog Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS 1, or PS1) 3pi survey. The first satellite, Laevens 3, is located at a heliocentric distance d=67+/-3 kpc. With total magnitude Mv=-4.4+/-0.3 half-light radius rh=7+/-2 pc, its properties resemble those outer halo globular clusters. second system, Draco II/Laevens 4 (Dra II), closer fainter...
Distance measurements to molecular clouds are important but often made separately for each cloud of interest, employing very different data and techniques. We present a large, homogeneous catalog distances clouds, most which unprecedented accuracy. determine using optical photometry stars along lines sight toward these obtained from PanSTARRS-1. simultaneously infer the reddenings stars, tracking full probability distribution function technique presented in Green et al. fit star-by-star...
The VLT Survey Telescope (VST) ATLAS is an optical ugriz survey aiming to cover ~4700deg^2 of the Southern sky similar depths as Sloan Digital Sky (SDSS). From reduced images and object catalogues provided by Cambridge Astronomical Surveys Unit we first find that median seeing ranges from 0.8 arcsec FWHM in i 1.0 u, significantly better than 1.2-1.5 for SDSS. 5 sigma magnitude limit stellar sources r_AB=22.7 all bands these limits are at least faint SDSS more equivalent galaxy photometry...
ABSTRACT Luminous quasars at <?CDATA $z\gt 5.6$?> can be studied in detail with the current generation of telescopes and provide us unique information on first gigayear universe. Thus far, these studies have been statistically limited by number known redshifts. Such are rare, therefore, wide-field surveys required to identify them, multiwavelength data separate them efficiently from their main contaminants, far more numerous cool dwarfs. In this paper, we update extend selection for $z\sim...
Recent searches by unbiased, wide-field surveys have uncovered a group of extremely luminous optical transients. The initial discoveries SN 2005ap the Texas Supernova Search and SCP-06F6 in deep Hubble pencil beam survey were followed Palomar Transient Factory confirmation host redshifts for other similar transients share common properties high luminosities (peak magnitudes ∼−21 to −23), blue colors, lack H or He spectral features. physical mechanism that produces luminosity is uncertain,...
Luminous distant quasars are unique probes of the high-redshift intergalactic medium (IGM) and growth massive galaxies black holes in early universe. Absorption due to neutral hydrogen IGM makes beyond a redshift very faint optical z band, thus locating at higher redshifts requires large surveys that sensitive above 1 micron. We report discovery three new quasars, corresponding an age universe Myr, selected as z-band dropouts Pan-STARRS1 survey. This increases number known from four seven....
Available deep samples of positional and photometric data on clusters galaxies are analysed to give estimates ellipticity position angle at various limiting magnitudes effective radii. Comparison the with those for elliptical shows that apparently more elongated than galaxies. angles cD in significant evidence alignment. Both these consistent an adiabatic perturbation theory cluster galaxy formation.
We present the discovery of a faint Milky Way satellite, Laevens 2/Triangulum II, found in Panoramic Survey Telescope And Rapid Response System 3π imaging data and confirmed with follow-up wide-field photometry from Large Binocular Cameras. The stellar system, an absolute magnitude MV = −1.8 ± 0.5, heliocentric distance , half-mass–radius shows remarkable similarity to faint, nearby, small satellites such as Willman 1, Segue 2, Boötes II. II further populates region parameter space for which...
RR Lyrae stars may be the best practical tracers of Galactic halo (sub-)structure and kinematics. The PanSTARRS1 (PS1) $3\pi$ survey offers multi-band, multi-epoch, precise photometry across much sky, but a robust identification in this data set poses challenge, given PS1's sparse, asynchronous multi-band light curves ($\lesssim 12$ epochs each five bands, taken over 4.5-year period). We present novel template fitting technique that uses well-defined physically motivated stars, demonstrate...