P. W. Draper
A5009924157- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Mycobacterium research and diagnosis
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Leprosy Research and Treatment
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Pharmacological Effects of Natural Compounds
- Tuberculosis Research and Epidemiology
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Cosmology and Gravitation Theories
- Distributed and Parallel Computing Systems
- Advanced Data Storage Technologies
- Planetary Science and Exploration
- Satellite Communication Systems
- Solar and Space Plasma Dynamics
- Computational Physics and Python Applications
- Parallel Computing and Optimization Techniques
- Infrared Target Detection Methodologies
- Advanced Computational Techniques and Applications
Durham University
2004-2024
Space Telescope Science Institute
2020
Princeton University
2013
Centre for the Study of Developing Societies
2011
TD Bank
2002
Kensington Health
2002
Farnham Road Hospital
2002
Transnational Press London
1995
National Institute for Health Research
1993
Jet Propulsion Laboratory
1970-1991
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 ($...
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,...
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...
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...
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...
ABSTRACT Numerical simulations have become one of the key tools used by theorists in all fields astrophysics and cosmology. The development modern that target largest existing computing systems exploit state-of-the-art numerical methods algorithms is thus crucial. In this paper, we introduce fully open-source highly-parallel, versatile, modular coupled hydrodynamics, gravity, cosmology, galaxy-formation code Swift. software package exploits hybrid shared- distributed-memory task-based...
Mycobacterium lepraemurium and M. microti (causal agent of vole tuberculosis) were isolated from tissues experimentally infected mice used to infect normal mouse peritoneal macrophage cultures. The cellular response these bacteria up 4 days after infection was studied quantitatively by electron microscopy. Prelabeling with ferritin facilitate observation fusion between secondary lysosomes in the cells phagosomes containing bacteria. All intraphagosomal, a high proportion them morphologically...
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....
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...
Current cosmological analyses, which use Type Ia supernova observations, combine (SN) samples to expand the redshift range beyond that of a single sample and increase overall size. The inhomogeneous photometric calibration between different SN is one largest systematic uncertainties parameter estimation. To place these on system, analyses currently observations small very bright flux standards Hubble Space Telescope system. We propose complementary method, called "Supercal," in we...
The Pan-STARRS1 Science Consortium have carried out a set of imaging surveys using the 1.4 giga-pixel GPC1 camera on PS1 telescope. As this is composed many individual electronic readouts, and covers very large field view, great care was taken to ensure that instrumental effects were corrected produce most uniform detector response possible. We present image detrending steps used as part processing data contained within public release Data Release 1 (DR1). In addition single processing,...
The Pan-STARRS Data Processing System is responsible for the steps needed to downloaded, archive, and process all images obtained by telescopes, including real-time detection of transient sources such as supernovae moving objects potentially hazardous asteroids. With a nightly data volume up 4 terabytes an archive over petabytes raw imagery, solidly in realm Big astronomy. full processing system consists several subsystems covering wide range necessary capabilities. This article describes...
In recent years, wide-field sky surveys providing deep multi-band imaging have presented a new path for indirectly characterizing the progenitor populations of core-collapse supernovae (SN): systematic light curve studies. We assemble set 76 grizy-band Type IIP SN curves from Pan-STARRS1, obtained over constant survey program 4 years and classified using both spectroscopy machine learning-based photometric techniques. develop apply Bayesian model full evolution each in sample. find no...
We probe the systematic uncertainties from 113 Type Ia supernovae (SNIa) in Pan-STARRS1 (PS1) sample along with 197 SN a combination of low-redshift surveys. The companion paper by Rest et al. (2013) describes photometric measurements and cosmological inferences PS1 sample. largest uncertainty stems calibration low-z samples. increase observed Calspec standards 7 to 10 used define system. SDSS-II systems are compared discrepancies up ~0.02 mag recovered. find proper way treat intrinsic...
We present a catalog of 9888 M, L and T dwarfs detected in the Pan-STARRS1 3$\pi$ Survey (PS1), covering three-quarters sky. Our contains nearly all known objects spectral types L0-T2 PS1 field, with as early M0 late T9, includes PS1, 2MASS, AllWISE, Gaia DR1 photometry. analyze different photometry reported by use two our to maximize both depth accuracy. Using parallaxes from literature, we construct empirical SEDs for field ultracool spanning 0.5-12 $\mu$m. determine typical colors M0-T9...