scholarly journals An Extensive Photometric Investigation of the W UMa System DK Cyg

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
M. M. Elkhateeb ◽  
M. I. Nouh ◽  
E. Elkholy ◽  
B. Korany
Keyword(s):  
Binary System ◽  
Evolutionary Status ◽  
Evolutionary Models ◽  
Period Increase ◽  
System A ◽  
New Period ◽  
Contact Binary ◽  
Photometric Investigation ◽  
Photometric Solution

DK Cyg (P=0.4707) is a contact binary system that undergoes complete eclipses. All the published photoelectric data have been collected and utilized to reexamine and update the period behavior of the system. A significant period increase with rate of 12.590 × 10−11 days/cycle was calculated. New period and ephemeris have been calculated for the system. A long term photometric solution study was performed and a light curve elements were calculated. We investigated the evolutionary status of the system using theoretical evolutionary models.

scholarly journals A Model for Contact Binary EP Andromedae

2012 ◽  
Vol 29 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Davood Manzoori
Keyword(s):  
Activity Cycle ◽  
Magnetic Activity ◽  
Close Binary ◽  
Evolutionary Status ◽  
Period Increase ◽  
System A ◽  
Contact Binary ◽  
The Times ◽  
Absolute Parameters ◽  
Program Version

AbstractThis paper presents the first comprehensive study of the EP And system, a contact binary. In this work the solution of the standard V light curve was obtained using the phoebe program (version 0.3c). Absolute parameters of the stellar components were then determined, enabling us to discuss the structure and evolutionary status of the close binary EP And. The times of minima data (‘O–C curve’) were analyzed. It was found that a third body with a period of 41.20 yr and mass 0.15 M⊙ is orbiting around the system. Also a modulating period of an 11.72-yr cycle along with a relative period increase of = 1.79 × 10−7 were obtained, which were attributed to the magnetic activity cycle and mass transfer with rate = 9.98 × 10−8 yr−1 between the components, respectively.

scholarly journals The Photometric Investigation of V921 Her Using the Lunar-Based Ultraviolet Telescope of Chang’e-3 Mission

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Xiao Zhou ◽  
Sheng-Bang Qian ◽  
Jia Zhang ◽  
Lin-Jia Li ◽  
Qi-Shan Wang
Keyword(s):  
Binary System ◽  
Thermal Contact ◽  
Primary Star ◽  
Light Minimum ◽  
Evolutionary Scenario ◽  
Total Luminosity ◽  
Massive Component ◽  
Contact Binary ◽  
Photometric Investigation ◽  
First Time

The light curve of V921 Her in ultraviolet band observed by the Lunar-based Ultraviolet Telescope (LUT) is analyzed by the Wilson-Devinney code. Our solutions conclude that V921 Her is an early type marginal contact binary system with an additional close-in component. The binary system is under poor thermal contact with a temperature difference of nearly 700 K between the two components. The close-in component contributes about 19% of the total luminosity in the triple system. Combining the radial velocity study together with our photometric solutions, the mass of the primary star and secondary one is calculated to beM1=1.784  (±0.055)M⊙,M2=0.403  (±0.012)M⊙. The evolutionary scenario of V921 Her is discussed. All times of light minimum of V921 Her available in the bibliography are taken into account and theO-Ccurve is analyzed for the first time. The most probable fitting results are discussed in the paper, which also confirm the existence of a third component (P3=10.2year) around the binary system. The period of V921 Her is also undergoing a continuously rapid increase at a rate ofdP/dt=+2.79×10-7  day·year-1, which may be due to mass transfer from the less massive component to the more massive one.

Photometric investigation of the evolved contact binary system DN Aur

1996 ◽  
Vol 246 (2) ◽  
pp. 291-298 ◽  
Author(s):  
S. N. Goderya ◽  
K. C. Leung ◽  
E. G. Schmidt
Keyword(s):  
Binary System ◽  
Contact Binary ◽  
Photometric Investigation

Photometric solution and period analysis of the contact binary system AH Cnc

2016 ◽  
Vol 16 (10) ◽  
pp. 157 ◽  
Author(s):  
Ying-Jiang Peng ◽  
Zhi-Quan Luo ◽  
Xiao-Bin Zhang ◽  
Li-Cai Deng ◽  
Kun Wang ◽  
...  
Keyword(s):  
Binary System ◽  
Period Analysis ◽  
Contact Binary ◽  
Photometric Solution

scholarly journals Complex Period Variations of the Neglected W UMa-type Binary System NY Lyrae

2009 ◽  
Vol 26 (1) ◽  
pp. 7-10 ◽  
Author(s):  
S.-B. Qian ◽  
L. Liu ◽  
L.-Y. Zhu
Keyword(s):  
Binary System ◽  
Orbital Period ◽  
Binary Star ◽  
Period Increase ◽  
Photometric And Spectroscopic Observations ◽  
Period Variations ◽  
Cyclic Oscillation ◽  
Careful Investigation ◽  
Interesting System

AbstractOrbital-period variations of the neglected W UMa-type binary star, NY Lyr, were analyzed based on two newly determined eclipse times together with the others compiled from the literature. A cyclic oscillation with a period of 82.1 yr and an amplitude of 0.0247 d was discovered to be superimposed on a continuous period increase (dP/dt = +1.33 × 10−7 d yr−1). After the long-term period increase and the large-amplitude cyclic oscillation were removed from the O–C diagram, the residuals suggest that there is another small-amplitude period oscillation (A4 = 0.0053 d, P4 = 19.4 years) in the orbital period changes. As in the cases of AH Cnc and AD Cnc, both the continuous period increase and the two cyclic period oscillations make NY Lyr an interesting system to study in the future. In order to understand the evolutionary state of the binary system, new photometric and spectroscopic observations and a careful investigation on those data are needed.

scholarly journals The eclipsing binary IU Per and its intrinsic oscillations

2008 ◽  
Vol 4 (S252) ◽  
pp. 429-430
Author(s):  
X. B. Zhang
Keyword(s):  
Time Series ◽  
Binary System ◽  
Fourier Analysis ◽  
Primary Component ◽  
Eclipsing Binary ◽  
Mode Identification ◽  
Short Period ◽  
Photometric Solution

AbstractThe results of a long-term time-series photometry of the short-period eclipsing binary IU Per are reported. The observation confirms the intrinsic δ Scuti-like pulsation of the star as discovered by previous authors. A photometric solution for the binary system was carried out with the new data. Based on which, the pure oscillation light variations from the mass-accreting primary component were extracted. A Fourier analysis reveals four pulsation modes. Combining with the photometric solution, a preliminary mode identification was given.

293 Enhancing Your Recovery: A Mobile Application for Patients Undergoing Vascular Surgery

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
S Hodge ◽  
K Pattabathula ◽  
J Jenkins ◽  
M Ogg
Keyword(s):  
Vascular Surgery ◽  
Mobile Application ◽  
Outpatient Appointment ◽  
Healthcare Settings ◽  
System A ◽  
University Of Technology ◽  
Operative Complications ◽  
Remote Consultations ◽  
Healthcare Assessment

Abstract Aim: With increasing demands on the healthcare system, a central (and currently essential) push for remote consultations, and an increasing number of co morbidities in the surgical population, the aim was to create an application that placed the focus on pre-hospital optimisation, education and autonomy – addressing these sector trends to enhance outcomes for patients and ease the burden on healthcare settings. Method After obtaining baseline data, I worked alongside students from the Queensland University of Technology to produce an application suitable for both iOS and android platforms. Results The application has four facets which mirror a patient’s journey from their initial outpatient appointment through to recovery. The application is easy to use, free to download and readily accessible. On opening the application, the user can select their planned operation and navigate along a personalised decision tree. Conclusions The application has been designed to educate and empower a patient to become an active participant in their care, leading to long-term changes in healthcare. Assessment is ongoing but early indications suggest that this will be a valuable tool in optimising outcomes for patients undergoing vascular surgery – leading to fewer post-operative complications and earlier restoration of functional status.

scholarly journals Light curve analysis of the late type binary V523 Cassiopeiae

2009 ◽  
pp. 45-48 ◽  
Author(s):  
O. Latkovic ◽  
M. Zboril ◽  
G. Djurasevic
Keyword(s):  
Light Curve ◽  
Monitoring Program ◽  
Neck Region ◽  
Bright Spot ◽  
Late Type ◽  
Light Curve Analysis ◽  
Type Contact ◽  
Contact Binary ◽  
Previous Solution

We present the analysis of V and R light curves of the late type contact binary V523 Cas for the season of 2006. These observations make part of the monitoring program aimed at studying the long-term light curve variability in this system. Our results confirm that the system is in an over contact configuration, and include a bright spot in the neck region of the cooler and larger primary. We compare these results with the previous solution, obtained for the season 2005 dataset and discuss the differences.

Sign in / Sign up

Export Citation Format

Share Document