- Keplerian periodogram for Doppler exoplanet detection: optimized computation and analytic significance thresholds
- Baluev, Roman V.
We consider the so-called Keplerian periodogram, in which the putative detectable signal is modelled by a highly non-linear Keplerian radial velocity function, appearing in Doppler exoplanetary surveys. We demonstrate that for planets on high-eccent …
- Generalized Fisher matrices
- Heavens, A. F.; Seikel, M.; Nord, B. D.; Aich, M.; Bouffanais, Y.; Bassett, B. A.; Hobson, M. P.
The Fisher Information Matrix formalism (Fisher 1935) is extended to cases where the data are divided into two parts (X, Y), where the expectation value of Y depends on X according to some theoretical model, and X and Y both have errors with arbitra …
- Visualizing Astronomical Data with Blender
- Kent, Brian R.
Astronomical data take on a multitude of forms – catalogs, data cubes, images, and simulations. The availability of software for rendering high-quality three-dimensional graphics lends itself to the paradigm of exploring the incredible parameter spa …
- DeBaCl: A Python Package for Interactive DEnsity-BAsed CLustering
- Kent, Brian P.; Rinaldo, Alessandro; Verstynen, Timothy
The level set tree approach of Hartigan (1975) provides a probabilistically based and highly interpretable encoding of the clustering behavior of a dataset. By representing the hierarchy of data modes as a dendrogram of the level sets of a density e …
- On the estimation of intensity for low S/N ratio narrow emission lines
- Rola, C.; Pelat, D.
The aim of this paper is to investigate the errors involved by the intensity measure of low signal-to-noise ratio narrow emission lines. We also studied the errors associated with line intensity ratios. The spectral data acquisition was simulated by …
- Sparse and Non-Negative BSS for Noisy Data
- Jérémy Rapin, Jérôme Bobin, Anthony Larue, Jean-Luc Starck
Non-negative blind source separation (BSS) has raised interest in various fields of research, as testified by the wide literature on the topic of non-negative matrix factorization (NMF). In this context, it is fundamental that the sources to be esti …
- Joint Planck and WMAP CMB Map Reconstruction
- J. Bobin, F. Sureau, J.-L. Starck, A. Rassat, P. Paykari
We present a novel estimate of the cosmological microwave background (CMB) map by combining the two latest full-sky microwave surveys: WMAP nine-year and Planck PR1. The joint processing benefits from a recently introduced component separation metho …
- GLIMPSE: Accurate 3D weak lensing reconstructions using sparsity
- Adrienne Leonard, François Lanusse, Jean-Luc Starck
We present GLIMPSE – Gravitational Lensing Inversion and MaPping with Sparse Estimators – a new algorithm to generate density reconstructions in three dimensions from photometric weak lensing measurements. This is an extension of earlier work in one …
- Dark signal correction for a lukecold frame-transfer CCD. New method and application to the solar imager of the PICARD space mission
- Hochedez, J.-F.; Timmermans, C.; Hauchecorne, A.; Meftah, M.
Context. Astrophysical observations must be corrected for their imperfections of instrumental origin. When charge-coupled devices (CCDs) are used, their dark signal is one such hindrance. In their pristine state, most CCD pixels are cool, that is, t …
- Flat-relative optimal extraction. A quick and efficient algorithm for stabilised spectrographs
- Zechmeister, M.; Anglada-Escudé, G.; Reiners, A.
Context. Optimal extraction is a key step in processing the raw images of spectra as registered by two-dimensional detector arrays to a one-dimensional format. Previously reported algorithms reconstruct models for a mean one-dimensional spatial prof …
- Optimizing the search for transiting planets in long time series
- Ofir, Aviv
Context. Transit surveys, both ground- and space-based, have already accumulated a large number of light curves that span several years. Aims: The search for transiting planets in these long time series is computationally intensive. We wish to opt …
- Optimized Principal Component Analysis on Coronagraphic Images of the Fomalhaut System
- Meshkat, Tiffany; Kenworthy, Matthew A.; Quanz, Sascha P.; Amara, Adam
We present the results of a study to optimize the principal component analysis (PCA) algorithm for planet detection, a new algorithm complementing angular differential imaging and locally optimized combination of images (LOCI) for increasing the con …
- 1SXPS: A Deep Swift X-Ray Telescope Point Source Catalog with Light Curves and Spectra
- Evans, P. A.; Osborne, J. P.; Beardmore, A. P.; Page, K. L.; Willingale, R.; Mountford, C. J.; Pagani, C.; Burrows, D. N.; Kennea, J. A.; Perri, M.; Tagliaferri, G.; Gehrels, N.
We present the 1SXPS (Swift-XRT point source) catalog of 151,524 X-ray point sources detected by the Swift-XRT in 8 yr of operation. The catalog covers 1905 deg2 distributed approximately uniformly on the sky. We analyze the data in two ways. First …
- Photometric classification of emission line galaxies with machine-learning methods
- Cavuoti, Stefano; Brescia, Massimo; D’Abrusco, Raffaele; Longo, Giuseppe; Paolillo, Maurizio
In this paper, we discuss an application of machine-learning-based methods to the identification of candidate active galactic nucleus (AGN) from optical survey data and to the automatic classification of AGNs in broad classes. We applied four differ …
- Bayes versus the virial theorem: inferring the potential of a galaxy from a kinematical snapshot
- Magorrian, John
We present a new framework for estimating a galaxy’s gravitational potential, Φ, from its stellar kinematics by adopting a fully non-parametric model for the galaxy’s unknown action-space distribution function, f(J). Having an expression for the jo …
- Beyond stacking: a maximum-likelihood method to constrain radio source counts below the detection threshold
- Mitchell-Wynne, Ketron; Santos, Mário G.; Afonso, José; Jarvis, Matt J.
We present a statistical method based on a maximum-likelihood approach to constrain the number counts of extragalactic sources below the nominal flux-density limit of continuum imaging surveys. We extract flux densities from a radio map using positi …
- Enabling non-parametric strong lensing models to derive reliable cluster mass distributions – WSLAP+
- Sendra, Irene; Diego, Jose M.; Broadhurst, Tom; Lazkoz, Ruth
In the strong lensing regime, non-parametric models struggle to achieve sufficient angular resolution for a meaningful derivation of the central cluster mass distribution. Cluster members perturb lensed images and generate additional images, requiri …
- TEMPONEST: a Bayesian approach to pulsar timing analysis
- Lentati, L.; Alexander, P.; Hobson, M. P.; Feroz, F.; van Haasteren, R.; Lee, K. J.; Shannon, R. M.
A new Bayesian software package for the analysis of pulsar timing data is presented in the form of TEMPONEST which allows for the robust determination of the non-linear pulsar timing solution simultaneously with a range of additional stochastic para …
- Bayesian lensing shear measurement
- Bernstein, Gary M.; Armstrong, Robert
We derive an estimator of weak gravitational lensing shear from background galaxy images that avoids noise-induced biases through a rigorous Bayesian treatment of the measurement. The derived shear estimator disposes with the assignment of elliptici …
- Hierarchical reverberation mapping
- Brewer, Brendon J.; Elliott, Tom M.
Reverberation mapping (RM) is an important technique in studies of active galactic nuclei (AGN). The key idea of RM is to measure the time lag τ between variations in the continuum emission from the accretion disc and subsequent response of the bro …