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.

Multiperiodicity in the Orbital Period Variations of the Eclipsing Binary System Z Per

2020 ◽  
Vol 64 (7) ◽  
pp. 619-627
Author(s):  
A. I. Khaliullina
Keyword(s):  
Binary System ◽  
Orbital Period ◽  
Eclipsing Binary ◽  
Period Variations

scholarly journals Multiwavelength Variability in the Symbiotic Nova V1016 CYG

2004 ◽  
Vol 194 ◽  
pp. 224-224
Author(s):  
Š. Parimucha ◽  
M. Vańko
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Orbital Period ◽  
Uv Spectroscopy ◽  
Infrared Photometry ◽  
Symbiotic System ◽  
Photoelectric Photometry ◽  
Mira Variable ◽  
Multiwavelength Variability

Analysis of the optical and infrared photometry together with UV spectroscopy led to discovery of the 15-years periodicity in the symbiotic system V1016 Cyg. This period could be interpreted as a orbital period in the binary system consisting of the Mira variable and the hot white dwarf.We have analyzed long-term optical photographic and UBV photoelectric photometry of V1016 Cyg. Collected observations cover pre- and post-outburst stages of the system. The light, curve suggests four stages of activity: the pre-out burst flare in 1949, the main nova-like outburst in 1904, and two post-outbursts, decreasing-amplitude flares in 1980 and 1994, respectively. Activity episodes affecting the system repeat with an interval of ~ 15 years. The ephemeris for the activity maxima is (see Parimucha et al., 2000).

scholarly journals Long-Term Orbital Period Variations for EU Hydrae

2003 ◽  
Vol 55 (2) ◽  
pp. 499-502 ◽  
Author(s):  
Sheng-Bang Qian ◽  
Soonthornthum Boonrucksar
Keyword(s):  
Orbital Period ◽  
Period Variations

Long-term optical variability of Her X-1

2018 ◽  
Vol 14 (S346) ◽  
pp. 239-241
Author(s):  
T. İçli ◽  
D. Koçak ◽  
K. Yakut
Keyword(s):  
Neutron Star ◽  
Binary System ◽  
Orbital Period ◽  
Optical Variability ◽  
National Observatory ◽  
Short Term ◽  
X Ray ◽  
Robotic Telescope

AbstractLong-term and short-term multicolor photometric variations of the X-ray binary system Her X-1 (HZ Her) has been studied. We obtained new VRI observations of the system by using the 60cm Robotic telescope at the TÜBİTAK National Observatory (TUG) in 2018. Using newly obtained data, we modified the orbital period of the binary system with a neutron star component.

scholarly journals The Light Curve and the Orbital Period Variations of Binary System TT Andromedae

2017 ◽  
Vol 07 (02) ◽  
pp. 112-123
Author(s):  
Davood Manzoori ◽  
Salar Abbasvand ◽  
Vahid Abbasvand
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Orbital Period ◽  
Period Variations

scholarly journals Mid-Cycle Observations of CR Boo and Estimation of the System’s Parameters

Data ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 113
Author(s):  
Daniela Boneva ◽  
Svetlana Boeva ◽  
Yanko Nikolov ◽  
Zorica Cvetković ◽  
Radoslav Zamanov
Keyword(s):  
Binary System ◽  
Observational Data ◽  
Orbital Period ◽  
Binary Star ◽  
Contact Point ◽  
Bright Spot ◽  
V Band ◽  
Phase Rotation

We present observations (with NAO Rozhen and AS Vidojevica telescopes) of the AM Canum Venaticorum (AM CVn) binary star CR Bootis (CR Boo) in the UBV bands. The data were obtained in two nights in July 2019, when the V band brightness was in the range of 16.1–17.0 mag. In both nights, a variability for a period of 25 ± 1 min and amplitude of about 0.2 magnitudes was visible. These brightness variations are most likely indications of “humps”. During our observational time, they appear for a period similar to the CR Boo orbital period. A possible reason of their origin is the phase rotation of the bright spot, placed in the contact point of the infalling matter and the outer disc edge. We estimated some of the parameters of the binary system, on the base of the observational data.

scholarly journals Orbital Period Variations in the NY Vir System, Revisited in the Light of New Data

2018 ◽  
Vol 27 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Özgür Baştürk ◽  
Ekrem Murat Esmer
Keyword(s):  
Binary System ◽  
Orbital Period ◽  
Variation Analysis ◽  
Eclipsing Binary ◽  
Period Variations ◽  
Observational Report ◽  
Best Fit ◽  
Circumbinary Planets

Abstract NY Virginis is an eclipsing binary system with a subdwarf B primary and an M type dwarf secondary. Recent studies (Qian et al. 2012; Lee et al. 2014) suggested the presence of two circumbinary planets with a few Jovian masses within the system. Lee et al. (2014) examined the orbital stabilities of the suggested planets, using the best-fit parameters derived from their eclipse timing variation analysis. They found that the outer companion should be ejected from the system in about 800 000 years. An observational report from Pulley et al. (2016) pointed out that the recent mideclipse times of the binary deviate significantly from the models suggested by Lee et al. (2014). In fact, variations in the orbital period of the system had already been recognized by many authors, but the parameters of these variations vary significantly as new data accumulate. Here, we analyze the eclipse timing variations of the NY Vir system, using new mid-eclipse times that we have obtained together with earlier published measurements in order to understand the nature of the system and constrain its parameters.

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.

Analysis of the photoelectric light curve and the orbital period variations of the binary system UU Andromedae

2015 ◽  
Vol 336 (6) ◽  
pp. 570-576 ◽  
Author(s):  
D. Manzoori ◽  
S. Abbasvand ◽  
F. Najafinezhad
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Orbital Period ◽  
Period Variations

Acquired tracheo-oesophageal fistula in a child with unrecognised tracheal foreign body

2021 ◽  
Vol 14 (4) ◽  
pp. e240947
Author(s):  
Kanokpan Ruangnapa ◽  
Wanaporn Anuntaseree ◽  
Kantara Saelim ◽  
Pharsai Prasertsan
Keyword(s):  
Foreign Body ◽  
Young Children ◽  
Respiratory Symptoms ◽  
Growth Failure ◽  
Late Diagnosis ◽  
Feeding Intolerance ◽  
Recurrent Pneumonia ◽  
High Index Of Suspicion ◽  
Careful Investigation

We report the case of a 6-month-old girl who presented with recurrent pneumonia and growth failure. After full examination, she was diagnosed with long-standing, unrecognised tracheal foreign body, which was then successfully removed. However, her chronic respiratory symptoms did not improve, and she also had feeding intolerance. The persistence of symptoms indicated a second bronchoscopy and finally an acquired tracheo-oesophageal fistula was diagnosed. This case emphasises the challenges in diagnosis of an inhaled foreign body in young children. Late diagnosis of this condition can cause significant morbidities. A high index of suspicion and careful investigation are very important to prevent long-term complications.

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