Expected Large Synoptic Survey Telescope (LSST) Yield of Eclipsing Binary Stars

In this paper we estimate the Large Synoptic Survey Telescope (LSST) yield of eclipsing binary stars, which will survey ~20,000 square degrees of the southern sky during the period of 10 years in 6 photometric passbands to r ~ 24.5. We generate a set of 10,000 eclipsing binary light curves sampled to the LSST time cadence across the whole sky, with added noise as a function of apparent magnitude. This set is passed to the Analysis of Variance (AoV) period finder to assess the recoverability rate for the periods, and the successfully phased light curves are passed to the artificial intelligence-based pipeline EBAI to assess the recoverability rate in terms of the eclipsing binaries' physical and geometric parameters. We find that, out of ~24 million eclipsing binaries observed by LSST with S/N>10 in mission life-time, ~28% or 6.7 million can be fully characterized by the pipeline. Of those, ~25% or 1.7 million will be double-lined binaries, a true treasure trove for stellar astrophysics.Comment: 19 pages, 7 figures. Accepted to AJ, to appear in issue 142:2 (Aug 2011

Pipeline Reduction of Binary Light Curves from Large-Scale Surveys

One 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.Comment: 14 pages, 8 figures, S240 IAU symposium proceeding

The impact of working capital management on the profitability of Croatian manufacturing SMEs

Working capital management is important because of its impact on the owner’s wealth, shown as the economic value of the enterprise, which is the result of interdependence of profitability and risk. Enterprises that invest more in working capital can expect lower levels of business risk, but unfavorable influences on profitability levels, and vice versa. Considering the importance of efficient working capital management, the main objective of this paper is to examine the relationship between working capital management and the profitability of Croatian small and medium-sized manufacturing enterprises (SMEs) and to provide empirical evidence on the effects of working capital management on the level of profitability of such enterprises. The panel analysis was used to examine the impact of accounts receivable, inventories, accounts payable, company size, sales growth, GDP growth and inflation rate on the profitability of Croatian manufacturing SMEs over a six-year period (2010-2015). The model confirmed the impact of inventories, accounts payable, and sales growth on the firm’s profitability level, while the effect of accounts receivable and company size on the company’s profitability was not confirmed, partially confirming the underlying working hypothesis. The control variables GDP and inflation were not statistically significant. It was found that manufacturing companies can increase their profitability by avoiding late payments to suppliers and by increasing inventory turnover, i.e., by holding inventory for as little time as possible. Moreover, businesses can increase their profitability by boosting sales growth

The data mining: An analysis of 20 eclipsing binary light-curves observed by the INTEGRAL/OMC

Twenty eclipsing binaries were selected for an analysis from a huge database of observations made by the INTEGRAL/OMC camera. The photometric data were processed and analyzed, resulting in a first light-curve study of these neglected eclipsing binaries. Most of the selected systems are the detached ones. The system ET Vel was discovered to be an eccentric one. Due to missing spectroscopic study of these stars, further detailed analyses are still needed.Comment: 4 pages, published in 2009 New Astronomy 14, 12

New Observations and Analysis of the Bright Semi-Detached Eclipsing Binary mu1 Sco

Using new and published photometric observations of mu1 Sco (HR 6247), spanning 70 years, a period of 1.4462700(5) days was determined. It was found that the epoch of primary minimum suggested by Shobbrook at HJD 2449534.178 requires an adjustment to HJD 2449534.17700(9) to align all the available photometric datasets. Using the resulting combined-data light-curve, radial velocities derived from IUE data and the modelling software PHOEBE, a new system solution for this binary was obtained. It appears that the secondary is close to, or just filling, its Roche-lobe.Comment: 4 figures, 6 tables, 9 pages, uses mn2e.sty, to be published in MNRA

Doživljaj ekspresivnosti autentičnih modusa u gregorijanskom koralu kod učenika primarnog odgoja i obrazovanja

Expressiveness of the church modes is reflected in their character and association of certain states with a specific mode or single Gregorian composition which possesses unique expressiveness. An important characteristic of Gregorian chant on the tonality level is diatonic singing based on scales without chromatics, using only one semitone in the tetrachord whose musical structure reflects the expressiveness of Gregorian chant. Such expressiveness achieves character specificities which each mode respectively reflects. Various modal material in the form of typical melodic shifts in a certain composition conditions the expressiveness of Gregorian music and influences the listening impression and assessment of individual Gregorian tunes. The goal of this work is to examine primary education students\u27 experiences of the expressiveness of Gregorian modes and explore if today\u27s auditory sense accustomed to two tonality genres, major and minor, recognises what has been stored in the heritage of Gregorian chant repertoire for centuries. The research was conducted in the school year 2018/2019 with students of first, second, third and fourth grade of primary school (N=100). The results have shown that first and second grade students express higher auditory sensibility in recognizing specific characteristic of authentic Gregorian modes. Third and fourth grade students are audibly less open and perceptive considering tonal character differences in the authentic Gregorian modes.Ekspresivnost starocrkvenih ljestvica odražava se kroz karakternost i pripisivanje izvjesnih stanja određenom modusu ili pojedinoj gregorijanskoj skladbi koja pokazuje specifičnu ekspresivnost. Važna karakteristika gregorijanskog pjevanja na tonskom planu je dijatonsko pjevanje temeljeno na ljestvicama bez kromatike koje koriste samo jedan polustupanj u tetrakordu čija glazbena struktura odražava ekspresivnost gregorijanskog pjevanja. U takvoj ekspresivnosti postižu se karakterne specifičnosti koje modus, svaki za sebe, odražava. Izražajnost gregorijanske glazbe uvelike je uvjetovana raznolikim modalnim materijalom koji se upotrebljava u pojedinoj skladbi pa će na slušni dojam i procjenu utjecati modalna struktura pojedinog gregorijanskog napjeva. Cilj rada je ispitati viđenje ekspresivnosti gregorijanskih modusa kod učenika primarnog odgoja i obrazovanja te istražiti može li današnja auditivnost koje ja navikla na dva tonska roda, dur i mol, prepoznati ono što se stoljećima baštini u repertoaru gregorijanskih napjeva. Istraživanje je provedeno u školskoj godini 2018./2019. s učenicima prvih, drugih, trećih i četvrtih razreda osnovne škole (N=100). Rezultati istraživanja pokazali su kako učenici prvih i drugih razreda iskazuju veću slušnu senzibilnost pri prepoznavanju određenih karakteristika autentičnih gregorijanskih modusa. Učenici trećih i četvrtih razreda manje su auditivno otvoreni i perceptivni s obzirom na karakterne razlike autentičnih gregorijanskih modusa

Precision timing of eclipsing binaries from TESS full frame images. Method and performance

Several hundreds of thousands of eclipsing binaries (EBs) are expected to be detected in the Transiting Exoplanet Survey Satellite (TESS) full frame images (FFIs). This represents a significant increase in the number of EBs available for eclipse timing variation studies. In this paper, we investigate the feasibility of performing precise eclipse timing of TESS EBs using the FFIs. To this end, we developed a fast, automated method and applied it to a sample of $\sim$100 EBs selected from the Villanova TESS EB catalog. Our timing analysis resulted in the detection of ten new triple candidates with outer periods shorter than $\sim$1300$\,$d. For five of them, we were able to constrain the outer orbit by analyzing independently the short-cadence (SC) and FFI data and to derive the minimum mass of the third body with a precision better than 4 per cent for SC and 12 per cent for FFI data. We then compared the results obtained from the two datasets and found that using the FFI data leads to (1) a degradation of both the accuracy and precision of the tertiary mass determination for the tightest EBs and (2) an overall underestimation of the third component's mass. However, we stress that our main conclusions on the nature of the detected signals do not depend on which dataset is used. This confirms the great potential of TESS FFIs, which will allow us to search for rare objects such as substellar circumbinary companions and compact triple stellar systems.Comment: Submitted to Ap