scholarly journals Orbital and physical parameters of eclipsing binaries from the ASAS catalogue – XI. CHIRON investigation of long-period binaries

2020 ◽  
Vol 500 (4) ◽  
pp. 4972-4988
Author(s):  
M Ratajczak ◽  
R K Pawłaszek ◽  
K G Hełminiak ◽  
M Konacki ◽  
P Sybilski ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Eclipsing Binaries ◽  
Physical Parameters ◽  
Correlation Technique ◽  
Red Giants ◽  
Evolved Stars ◽  
V Band ◽  
The Masses ◽  
Cross Correlation Technique ◽  
Better Than

ABSTRACT We present the results of a spectroscopic campaign on eclipsing binaries with long orbital period (P = 20–75 d) carried out with the CHIRON spectrograph. Physical and orbital solutions for seven systems were derived from the V band, and I band ASAS, WASP, and TESS photometry, while radial velocities were calculated from high-quality optical spectra using a two-dimensional cross-correlation technique. The atmospheric parameters of the stars have been determined from the separated spectra. Most of our targets are composed of evolved stars (subgiants or red giants) but two systems show components in different phases of evolution and one possible merger. For four binaries, the masses and radii of the components were obtained with precision better than $3{{\ \rm per\ cent}}$. These objects provide very valuable information on stellar evolution.

scholarly journals The Mass-Luminosity Relation From Binaries

1998 ◽  
Vol 11 (1) ◽  
pp. 419-420
Author(s):  
David W. Latham
Keyword(s):  
Eclipsing Binaries ◽  
M Dwarfs ◽  
Direct Measurements ◽  
Nearby Stars ◽  
The Masses ◽  
Stellar Masses ◽  
M Dwarf ◽  
Magnitude Difference ◽  
Astrometric Binaries ◽  
Better Than

What is known about the masses of main-sequence stars from the analysis of binary orbits? Double-lined eclipsing binaries are the main source of very precise stellar masses and radii (e.g. Andersen 1997), contributing more than 100 determinations with better than 2% precision over the range 0.6 to 20 Mʘ. For lower-mass stars we are forced to turn to nearby systems with astrometric orbits (e.g. Henry et al. 1993). Not only is the number of good mass determinations from such systems smaller, but also the precision is generally poorer. We are approaching an era when interferometers should have a major impact by supplying good astrometric orbits for dozens of double-lined systems. Already we are beginning to see the sorts of results to expect from this (e.g. Torres et al. 1997). Figure 1. Mass vs. absolute V magnitude for eclipsing binaries (circles) and nearby astrometric binaries (squares) Figure 1 is an updated version of a diagram presented by Henry et al. (1993, their Figure 2). It shows the general run of mass determinations from about 10 Mʘ down to the substellar limit near 0.075 Mʘ. Ninety of the points in Figure 1 are for eclipsing binary masses from Andersen’s review (1991) and are plotted as open circles. The results for eclipsing binaries published since 1991 are plotted as 30 filled circles, adopting the same limit of 2% for the mass precision. In most cases the uncertainties are similar to the size of the symbols. Especially noteworthy is the pair of new points for CM Draconis (Metcalfe et al. 1996) with masses near 0.25 Mʘ. Together with the points for YY Geminorum near 0.6 Mʘ, these are the only M dwarfs that have precise mass determinations. For the most part we are forced to rely on nearby stars with astrometric orbits, to fill in the M dwarf region of the diagram. We have used filled squares in Figure 1 for 29 such systems from Henry et al. (1993), updated using 14 new parallaxes from Hipparcos and 4 from the new Yale Parallax Catalog (1995). Gliese 508 is not included, because it is now known to be a triple, while Gliese 67AB, 570BC, and 623AB are not included because there are not yet any direct measurements of the V magnitude difference for these systems.

scholarly journals The emergence of the red sequence at z~2 seen through galaxy clustering in the UKIDSS UDS

2012 ◽  
Vol 8 (S295) ◽  
pp. 105-108
Author(s):  
William G. Hartley ◽  
Omar Almaini ◽  
Alice Mortlock ◽  
Chris Conselice ◽  
Keyword(s):  
Dark Matter ◽  
Cross Correlation ◽  
Near Infrared ◽  
Correlation Technique ◽  
Dark Matter Halos ◽  
Star Forming ◽  
Deep Survey ◽  
Cross Correlation Technique ◽  
Infrared Survey

AbstractWe use the UKIDSS Ultra-Deep Survey, the deepest degree-scale near-infrared survey to date, to investigate the clustering of star-forming and passive galaxies to z ~ 3.5. Our new measurements include the first determination of the clustering for passive galaxies at z > 2, which we achieve using a cross-correlation technique. We find that passive galaxies are the most strongly clustered, typically hosted by massive dark matter halos with Mhalo > 1013 M⊙ irrespective of redshift or stellar mass. Our findings are consistent with models in which a critical halo mass determines the transition from star-forming to passive galaxies.

Raman Chemical Imaging of Explosive-Contaminated Fingerprints

2009 ◽  
Vol 63 (11) ◽  
pp. 1197-1203 ◽  
Author(s):  
E. D. Emmons ◽  
A. Tripathi ◽  
J. A. Guicheteau ◽  
S. D. Christesen ◽  
A. W. Fountain
Keyword(s):  
Cross Correlation ◽  
Chemical Imaging ◽  
Correlation Technique ◽  
Bright Field ◽  
Characteristic Region ◽  
Biometric Analysis ◽  
Imaging Results ◽  
Raman Chemical Imaging ◽  
Cross Correlation Technique ◽  
Field Imaging

Raman chemical imaging (RCI) has been used to detect and identify explosives in contaminated fingerprints. Bright-field imaging is used to identify regions of interest within a fingerprint, which can then be examined to determine their chemical composition using RCI and fluorescence imaging. Results are presented where explosives in contaminated fingerprints are identified and their spatial distributions are obtained. Identification of explosives is obtained using Pearson's cosine cross-correlation technique using the characteristic region (500–1850 cm−1) of the spectrum. This study shows the ability to identify explosives nondestructively so that the fingerprint remains intact for further biometric analysis. Prospects for forensic examination of contaminated fingerprints are discussed.

Optoelectronic sensor applied to airflow velocity measurements through cross-correlation technique

2021 ◽  
Author(s):  
Alexandre Allil ◽  
Fábio Dutra ◽  
Cesar Cosenza Carvalho ◽  
Alex Dante ◽  
Regina Allil ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Correlation Technique ◽  
Velocity Measurements ◽  
Airflow Velocity ◽  
Optoelectronic Sensor ◽  
Cross Correlation Technique

scholarly journals SuperCLASS – I. The super cluster assisted shear survey: Project overview and data release 1

2020 ◽  
Vol 495 (2) ◽  
pp. 1706-1723 ◽  
Author(s):  
Richard A Battye ◽  
Michael L Brown ◽  
Caitlin M Casey ◽  
Ian Harrison ◽  
Neal J Jackson ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Near Infrared ◽  
Correlation Technique ◽  
Large Array ◽  
Photometric Redshifts ◽  
Very Large Array ◽  
Infrared Observations ◽  
Data Release ◽  
L Band ◽  
Cross Correlation Technique

ABSTRACT The SuperCLuster Assisted Shear Survey (SuperCLASS) is a legacy programme using the e-MERLIN interferometric array. The aim is to observe the sky at L-band (1.4 GHz) to a r.m.s. of $7\, \mu {\rm Jy}\,$beam−1 over an area of $\sim 1\, {\rm deg}^2$ centred on the Abell 981 supercluster. The main scientific objectives of the project are: (i) to detect the effects of weak lensing in the radio in preparation for similar measurements with the Square Kilometre Array (SKA); (ii) an extinction free census of star formation and AGN activity out to z ∼ 1. In this paper we give an overview of the project including the science goals and multiwavelength coverage before presenting the first data release. We have analysed around 400 h of e-MERLIN data allowing us to create a Data Release 1 (DR1) mosaic of $\sim 0.26\, {\rm deg}^2$ to the full depth. These observations have been supplemented with complementary radio observations from the Karl G. Jansky Very Large Array (VLA) and optical/near infrared observations taken with the Subaru, Canada-France-Hawaii, and Spitzer Telescopes. The main data product is a catalogue of 887 sources detected by the VLA, of which 395 are detected by e-MERLIN and 197 of these are resolved. We have investigated the size, flux, and spectral index properties of these sources finding them compatible with previous studies. Preliminary photometric redshifts, and an assessment of galaxy shapes measured in the radio data, combined with a radio-optical cross-correlation technique probing cosmic shear in a supercluster environment, are presented in companion papers.

scholarly journals Spectroscopy of southern δ Scuti stars

2004 ◽  
Vol 193 ◽  
pp. 275-278
Author(s):  
Malcolm Cropp ◽  
Karen R. Pollard ◽  
Jovan Skuljan
Keyword(s):  
New Zealand ◽  
Spectral Line ◽  
Radial Velocity ◽  
Spectroscopic Data ◽  
Cross Correlation ◽  
Correlation Technique ◽  
Echelle Spectrograph ◽  
Cross Correlation Technique ◽  
Scuti Stars ◽  
Δ Scuti Stars

AbstractFour δ Scuti stars were observed with the HERCULES fibrefed échelle spectrograph at Mount John University Observatory, New Zealand. These observations were analysed by looking at the radial velocity variations as given by a cross-correlation technique as well as spectral line moment variations. These results were compared to published photometric studies of these stars to see if the modes identified in the photometry were also present in the spectroscopic data obtained.

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