scholarly journals Pipeline Reduction of Binary Light Curves from Large–Scale Surveys

2006 ◽  
Vol 2 (S240) ◽  
pp. 217-229
Author(s):  
Andrej Prša ◽  
Tomaž Zwitter

AbstractOne of the most important changes in observational astronomy of the 21st Century is a rapid shift from classical object-by-object observations to extensive automatic surveys. As CCD detectors are getting better and their prices are getting lower, more and more small and medium-size observatories are refocusing their attention to detection of stellar variability through systematic sky-scanning missions. This trend is aditionally powered by the success of pioneering surveys such as ASAS, DENIS, OGLE, TASS, their space counterpart Hipparcos and others. Such surveys produce massive amounts of data and it is not at all clear how these data are to be reduced and analysed. This is especially striking in the eclipsing binary (EB) field, where most frequently used tools are optimized for object-by-object analysis. A clear need for thorough, reliable and fully automated approaches to modeling and analysis of EB data is thus obvious. This task is very difficult because of limited data quality, non-uniform phase coverage and solution degeneracy. This paper reviews recent advancements in putting together semi-automatic and fully automatic pipelines for EB data processing. Automatic procedures have already been used to process Hipparcos data, LMC/SMC observations, OGLE and ASAS catalogs etc. We discuss the advantages and shortcomings of these procedures.

2020 ◽  
Vol 492 (3) ◽  
pp. 4019-4032 ◽  
Author(s):  
Collin A Politsch ◽  
Jessi Cisewski-Kehe ◽  
Rupert A C Croft ◽  
Larry Wasserman

ABSTRACT Trend filtering – first introduced into the astronomical literature in Paper I of this series – is a state-of-the-art statistical tool for denoising 1D signals that possess varying degrees of smoothness. In this work, we demonstrate the broad utility of trend filtering to observational astronomy by discussing how it can contribute to a variety of spectroscopic and time-domain studies. The observations we discuss are (1) the Lyman-α (Lyα) forest of quasar spectra; (2) more general spectroscopy of quasars, galaxies, and stars; (3) stellar light curves with planetary transits; (4) eclipsing binary light curves; and (5) supernova light curves. We study the Lyα forest in the greatest detail – using trend filtering to map the large-scale structure of the intergalactic medium along quasar-observer lines of sight. The remaining studies share broad themes of: (1) estimating observable parameters of light curves and spectra; and (2) constructing observational spectral/light-curve templates. We also briefly discuss the utility of trend filtering as a tool for 1D data reduction and compression.


2008 ◽  
Author(s):  
Douglas L. Westphal ◽  
Cynthia A. Curtis ◽  
Annette L. Walker

2007 ◽  
Author(s):  
Douglas L. Westphal ◽  
Cynthia A. Curtis ◽  
Annette L. Walker

2019 ◽  
Vol 15 (1) ◽  
pp. 54-56
Author(s):  
Stelina Alkagiet ◽  
Konstantinos Tziomalos

Primary aldosteronism (PA) is not only a leading cause of secondary and resistant hypertension, but is also quite frequent in unselected hypertensive patients. Moreover, PA is associated with increased cardiovascular risk, which is disproportionate to BP levels. In addition, timely diagnosis of PA and prompt initiation of treatment attenuate this increased risk. On the other hand, there are limited data regarding the usefulness of screening for PA in all asymptomatic or normokalemic hypertensive patients. More importantly, until now, no well-organized, large-scale, prospective, randomized controlled trial has proved the effectiveness of screening for PA for improving clinical outcome. Accordingly, until more relevant data are available, screening for PA should be considered in hypertensive patients with spontaneous or diuretic-induced hypokalemia as well as in those with resistant hypertension. However, screening for PA in all hypertensive patients cannot be currently recommended.


2008 ◽  
Vol 25 (5) ◽  
pp. 287-300 ◽  
Author(s):  
B. Martin ◽  
A. Al‐Shabibi ◽  
S.M. Batraneanu ◽  
Ciobotaru ◽  
G.L. Darlea ◽  
...  

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