Double, triple and quadruple-line spectroscopic binary candidates within the Gaia-ESO Survey

2017 ◽  
Vol 12 (S330) ◽  
pp. 329-330
Author(s):  
Thibault Merle ◽  
Sophie Van Eck ◽  
Alain Jorissen ◽  
Mathieu Van der Swaelmen ◽  
Gregor Traven ◽  
...  

AbstractThe Gaia-ESO Survey (GES, Gilmore et al. 2012) provides a unique opportunity to detect spectroscopically multiplicity among different populations of the Galaxy using the cross-correlation functions (CCFs). We present here the GES internal Data Release 4 (iDR4) results of the detection of double, triple and quadruple-line spectroscopic binary candidates (SBs) and discuss some peculiar systems.

1987 ◽  
Vol 35 (3) ◽  
pp. 305-312 ◽  
Author(s):  
A. Shaar ◽  
C. Woodcock ◽  
P. Davies

1988 ◽  
Vol 129 ◽  
pp. 233-234
Author(s):  
Aubrey D. Haschick ◽  
Willem A. Baan ◽  
Matthew H. Schneps ◽  
Mark J. Reid ◽  
James M. Moran

On 1984 October 6 we conducted a 3-station intercontinental Mark II VLBI experiment in order to study the very luminous water vapor maser source in the nucleus of the galaxy NGC 3079, which was detected first by Haschick and Baan (1985) using the Haystack Observatory 36.6 m antenna. The cross correlation spectrum for the longest Owens Valley to MPI baseline is presented in Figure 1 and shows the phase variation across the width of the brightest feature at 955.7 km s−1 to be less than 10 degrees of phase.


2018 ◽  
Vol 9 (2) ◽  
pp. 216-222
Author(s):  
G. V. Galyk ◽  
Z. Y. Fedorovych ◽  
E. I. Lychkovsky ◽  
D. I. Sanagursky

Germ cells of aquatic organisms are complex systems whose growth and development depends on many factors, one of which is the composition of the aquatic environment. We used parameters in our analysis from aggregate data available from published literature. They are data of the transmembrane potential of the germinal cells of Misgurnus fossilis (Linnaeus, 1758) at the development stage from 180th to 360th minutes. Embryos were incubated in an environment with nickel, cobalt, tin, and zinc ions and without them. Plotted lines of the transmembrane potential were digitized and calibrated at intervals of 10 minutes. Rows of numerical values of the transmembrane potentials were obtained. These rows were used for calculation of autocorrelation and cross-cross-correlation functions. It was established that the transmembrane potential describes nonperiodic and quasi-periodic oscillations. The higher statistically significant values of the autocorrelation coefficients were observed in the first lags. Autocorrelation analysis indicates that the periods of oscillations of the transmembrane potential increase with the action of nickel, cobalt, tin and zinc on the germ. The phenomena and processes that occur in the germ cell are well reflected at the initial stages of the auto-correction and are lost when the magnitude of the lag increases. The degree of similarity of transmembrane potentials with the help of cross-correlation analysis is quantitatively characterized. The distribution of fluctuations of cross-correlation functions with complex dynamics, which arise with time shifts both in the forward and reverse directions, were established. It is established that for large values of time shifts, the cross-correlation coefficient is a low-informative indicator, since information about the influence of the factor on the living system is lost. A graph for a given time shift was constructed. The connection between the nodes is the magnitude of the cross-correlation coefficients between the vapor of the transmembrane potentials, which indicate the degree of similarity of the bioelectric processes. Graphs will be used for qualitative and quantitative study of system dynamics. The obtained results confirm the existence of a close relationship between environmental nickel, cobalt, tin, and zinc and the oscillation of transmembrane potential during early embryogenesis.


2020 ◽  
Vol 494 (4) ◽  
pp. 5603-5618 ◽  
Author(s):  
C Gheller ◽  
F Vazza

ABSTRACT We used magnetohydrodynamical cosmological simulations to investigate the cross-correlation between different observables (i.e. X-ray emission, Sunyaev–Zeldovich (SZ) signal at 21 cm, H i temperature decrement, diffuse synchrotron emission, and Faraday Rotation) as a probe of the diffuse matter distribution in the cosmic web. We adopt a uniform and simplistic approach to produce synthetic observations at various wavelengths, and we compare the detection chances of different combinations of observables correlated with each other and with the underlying galaxy distribution in the volume. With presently available surveys of galaxies and existing instruments, the best chances to detect the diffuse gas in the cosmic web outside of haloes is by cross-correlating the distribution of galaxies with SZ observations. We also find that the cross-correlation between the galaxy network and the radio emission or the Faraday Rotation can already be used to limit the amplitude of extragalactic magnetic fields, well outside of the cluster volume usually explored by existing radio observations, and to probe the origin of cosmic magnetism with the future generation of radio surveys.


2020 ◽  
pp. 9-16
Author(s):  
Telman A. Aliev ◽  
Naila F. Musaeva ◽  
Narmin E. Rzayeva ◽  
Ana I. Mammadova

The authors analyze the factors affecting the errors in the estimates of the correlation functions of the noisy signals when using traditional calculation algorithms. It is shown that the sum noise of the noisy signal in many cases consists of the noise caused by external factors and the noise caused by the initiation of various defects during the operation of control objects. For this reason, in order to eliminate the error in the results of the correlation analysis of noisy signals, it is necessary to create algorithms and technologies for determining the estimate of the noise variance and the cross-correlation functions between the useful signal and the noise. For this purpose, appropriate algorithms and technologies are proposed that open up the possibility of reducing the error of traditional technologies for determining the estimates of correlation functions. With the purpose of reducing the error of the results of correlation analysis, a technology is proposed for determining the approximate equivalent samples of the noise of the noisy signals. It is shown that using the equivalent noise samples, it is possible to obtain results that are identical to the results of using real samples of the noise in the correlation analysis of the same signals. Moreover, by extracting the equivalent noise samples from the noisy signal, the equivalent samples of the useful signal are also determined, which allow determining the estimates equivalent to the estimates of the correlation functions of the useful signal. At the same time, having equivalent noise samples and useful signal samples, the estimates of the cross-correlation function between the useful signal and the noise are determined. The study have shown that despite certain errors in the equivalent samples compared to the true samples, with a sufficient observation time using equivalent samples, the error of traditional technologies for the correlation analysis of noisy signals can be significantly reduced. These technologies can also be used to correct errors in the results of the analysis of experimental data in information-measuring and other measuring complexes and systems, which will significantly improve their metrological characteristics.


2005 ◽  
Vol 362 (2) ◽  
pp. 711-726 ◽  
Author(s):  
Xiaohu Yang ◽  
H. J. Mo ◽  
Frank C. van den Bosch ◽  
Simone M. Weinmann ◽  
Cheng Li ◽  
...  

2014 ◽  
Vol 10 (S306) ◽  
pp. 202-205 ◽  
Author(s):  
Federico Bianchini ◽  
Andrea Lapi

AbstractWe present the first measurement of the correlation between the map of the CMB lensing potential derived from the Planck nominal mission data and z ≳ 1.5 galaxies detected by Herschel-ATLAS (H-ATLAS) survey covering about 550 deg2. We detect the cross-power spectrum with a significance of ∼ 8.5σ, ruling out the absence of correlation at 9σ. We check detection with a number of null tests. The amplitude of cross-correlation and the galaxy bias are estimated using joint analysis of the cross-power spectrum and the galaxy survey auto-spectrum, which allows to break degeneracy between these parameters. The estimated galaxy bias is consistent with previous estimates of the bias for the H-ATLAS data, while the cross-correlation amplitude is higher than expected for a ΛCDM model. The content of this work is to appear in a forthcoming paper Bianchini, et al. (2014).


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