- Improving the precision matrix for precision cosmology
- Paz, Dante J.; Sánchez, Ariel G.
The estimation of cosmological constraints from observations of the large-scale structure of the Universe, such as the power spectrum or the correlation function, requires the knowledge of the inverse of the associated covariance matrix, namely the …
- A demonstration of position angle-only weak lensing shear estimators on the GREAT3 simulations
- Whittaker, Lee; Brown, Michael L.; Battye, Richard A.
We develop and apply the position angle-only shear estimator of Whittaker, Brown & Battye to realistic galaxy images. This is done by demonstrating the method on the simulations of the third GRavitational lEnsing Accuracy Testing (GREAT3) challenge, …
- On weak lensing shape noise
- Niemi, Sami-Matias; Kitching, Thomas D.; Cropper, Mark
One of the most powerful techniques to study the dark sector of the Universe is weak gravitational lensing. In practice, to infer the reduced shear, weak lensing measures galaxy shapes, which are the consequence of both the intrinsic ellipticity of …
- Mapping stellar content to dark matter haloes using galaxy clustering and galaxy-galaxy lensing in the SDSS DR7
- Zu, Ying; Mandelbaum, Rachel
The mapping between the distributions of the observed galaxy stellar mass and the underlying dark matter haloes provides the crucial link from theories of large-scale structure formation to interpreting the complex phenomena of galaxy formation and …
- Non-Gaussian Error Distributions of LMC Distance Moduli Measurements
- Crandall, Sara; Ratra, Bharat
We construct error distributions for a compilation of 232 Large Magellanic Cloud (LMC) distance moduli values from de Grijs et al. that give an LMC distance modulus of (m – M)0 = 18.49 ± 0.13 mag (median and 1σ symmetrized error). Central estimate …
- Precise astronomical flux calibration and its impact on studying the nature of the dark energy
- Stubbs, Christopher W.; Brown, Yorke J.
Measurements of the luminosity of Type Ia supernovae versus redshift provided the original evidence for the accelerating expansion of the Universe and the existence of dark energy. Despite substantial improvements in survey methodology, systematic u …
- Temperature as a third dimension in column-density mapping of dusty astrophysical structures associated with star formation
- Marsh, K. A.; Whitworth, A. P.; Lomax, O.
We present point process mapping (<monospace>PPMAP</monospace>), a Bayesian procedure that uses images of dust continuum emission at multiple wavelengths to produce resolution-enhanced image cubes of differential column density as a function of dust …
- The JCMT Gould Belt Survey: a quantitative comparison between SCUBA-2 data reduction methods
- Mairs, S.; Johnstone, D.; Kirk, H.; Graves, S.; Buckle, J.; Beaulieu, S. F.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Hatchell, J.; Jenness, T.; Mottram, J. C.; Nutter, D.; Pattle, K.; Pineda, J. E.; Salji, C.; Francesco, J. Di; Hogerheijde, M. R.; Ward-Thompson, D.; JCMT Gould Belt survey Team
Performing ground-based submillimetre observations is a difficult task as the measurements are subject to absorption and emission from water vapour in the Earth’s atmosphere and time variation in weather and instrument stability. Removing these feat …
- Graph-based interpretation of the molecular interstellar medium segmentation
- Colombo, D.; Rosolowsky, E.; Ginsburg, A.; Duarte-Cabral, A.; Hughes, A.
We present a generalization of the giant molecular cloud identification problem based on cluster analysis. The method we designed, SCIMES (Spectral Clustering for Interstellar Molecular Emission Segmentation) considers the dendrogram of emission in …
- Automated detection of solar eruptions
- Hurlburt, N.
Observation of the solar atmosphere reveals a wide range of motions, from small scale jets and spicules to global-scale coronal mass ejections (CMEs). Identifying and characterizing these motions are essential to advancing our understanding of the d …
- The Data Reduction Pipeline for the Apache Point Observatory Galactic Evolution Experiment
- Nidever, David L.; Holtzman, Jon A.; Allende Prieto, Carlos; Beland, Stephane; Bender, Chad; Bizyaev, Dmitry; Burton, Adam; Desphande, Rohit; Fleming, Scott W.; García Pérez, Ana E.; Hearty, Fred R.; Majewski, Steven R.; Mészáros, Szabolcs; Muna, Demitri; Nguyen, Duy; Schiavon, Ricardo P.; Shetrone, Matthew; Skrutskie, Michael F.; Sobeck, Jennifer S.; Wilson, John C.
The Apache Point Observatory Galactic Evolution Experiment (APOGEE), part of the Sloan Digital Sky Survey III, explores the stellar populations of the Milky Way using the Sloan 2.5-m telescope linked to a high resolution (R ˜ 22,500), near-infrared …
- The Difference Imaging Pipeline for the Transient Search in the Dark Energy Survey
- Kessler, R.; Marriner, J.; Childress, M.; Covarrubias, R.; D’Andrea, C. B.; Finley, D. A.; Fischer, J.; Foley, R. J.; Goldstein, D.; Gupta, R. R.; Kuehn, K.; Marcha, M.; Nichol, R. C.; Papadopoulos, A.; Sako, M.; Scolnic, D.; Smith, M.; Sullivan, M.; Wester, W.; Yuan, F.; Abbott, T.; Abdalla, F. B.; Allam, S.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Carnero Rosell, A.; Carrasco Kind, M.; Castander, F. J.; Crocce, M.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Eifler, T. F.; Fausti Neto, A.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D. J.; Kuropatkin, N.; Li, T. S.; Maia, M. A. G.; Marshall, J. L.; Martini, P.; Miller, C. J.; Miquel, R.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sanchez, E.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Tarle, G.; Thaler, J.; Thomas, R. C.; Tucker, D.; Walker, A. R.; DES Collaboration
We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 Februa …
- Generating Optimal Initial Conditions for Smoothed Particle Hydrodynamics Simulations
- Diehl, S.; Rockefeller, G.; Fryer, C. L.; Riethmiller, D.; Statler, T. S.
We review existing smoothed particle hydrodynamics setup methods and outline their advantages, limitations, and drawbacks. We present a new method for constructing initial conditions for smoothed particle hydrodynamics simulations, which may also be …
- TORUS-3DPDR: a self-consistent code treating three-dimensional photoionization and photodissociation regions
- Bisbas, T. G.; Haworth, T. J.; Barlow, M. J.; Viti, S.; Harries, T. J.; Bell, T.; Yates, J. A.
The interaction of ionizing and far-ultraviolet radiation with the interstellar medium is of great importance. It results in the formation of regions in which the gas is ionized, beyond which are photodissociation regions (PDRs) in which the gas tra …
- The EAGLE simulations of galaxy formation: the importance of the hydrodynamics scheme
- Schaller, Matthieu; Dalla Vecchia, Claudio; Schaye, Joop; Bower, Richard G.; Theuns, Tom; Crain, Robert A.; Furlong, Michelle; McCarthy, Ian G.
We present results from a subset of simulations from the `Evolution and Assembly of GaLaxies and their Environments’ (EAGLE) suite in which the formulation of the hydrodynamics scheme is varied. We compare simulations that use the same subgrid model …
- Newtonian CAFE: a new ideal MHD code to study the solar atmosphere
- González-Avilés, J. J.; Cruz-Osorio, A.; Lora-Clavijo, F. D.; Guzmán, F. S.
We present a new code designed to solve the equations of classical ideal magnetohydrodynamics (MHD) in three dimensions, submitted to a constant gravitational field. The purpose of the code centres on the analysis of solar phenomena within the photo …
- A catalog of visual-like morphologies in the 5 CANDELS fields using deep-learning
- M. Huertas-Company, R. Gravet, G. Cabrera-Vives, P.G. Pérez-González, J.S. Kartaltepe, G. Barro, M. Bernardi, S. Mei, F. Shankar, P. Dimauro, E.F. Bell, D. Kocevski, D.C. Koo, S.M. Faber, D.H. Mcintosh
We present a catalog of visual like H-band morphologies of ∼50.000 galaxies (Hf160w<24.5) in the 5 CANDELS fields (GOODS-N, GOODS-S, UDS, EGS and COSMOS). Morphologies are estimated with Convolutional Neural Networks (ConvNets). The median redshif …
- A Flight through the Universe
- Aragon-Calvo, M.A., SubbaRao, M.
The authors describe the creation of a tridimensional fly-through animation across the largest map of galaxies to date. This project represented a challenge: creating a scientifically accurate representation of the galaxy distribution that was aesth …
- Streaming Algorithms for Halo Finders
- Zaoxing Liu ; Ivkin, N. ; Lin Yang ; Neyrinck, M
Cosmological N-body simulations are essential for studies of the large-scale distribution of matter and galaxies in the Universe. This analysis often involves finding clusters of particles and retrieving their properties. Detecting such “halos” amon …
- Enhanced flyby science with onboard computer vision: Tracking and surface feature detection at small bodies
- Fuchs, Thomas J.; Thompson, David R.; Bue, Brian D.; Castillo-Rogez, Julie; Chien, Steve A.; Gharibian, Dero; Wagstaff, Kiri L.
Spacecraft autonomy is crucial to increase the science return of optical remote sensing observations at distant primitive bodies. To date, most small bodies exploration has involved short timescale flybys that execute prescripted data collection seq …