Periods of Outbursts and Standstills and Variations in Parameters of Two Z Cam Stars: Z Cam and AT Cnc
Abstract
1. Introduction
2. Observational Data and Observational Effects
3. Color Indices and Color Temperatures
4. System Parameters, Calculation and Comparison
4.1. Radii and Orbital Separations
Object/ Parameter | Porb [days] | Mwd [M⊙] | M2 [M⊙] | q | Teff [K] (of WD) | R1 [R⊙] | A [R⊙] | R2 [R⊙] |
---|---|---|---|---|---|---|---|---|
Z Cam | 0.289 [11] | 0.99 ± 0.15 [12] | 0.70 ± 0.02 [8] | 0.71 ± 0.10 [12] | 57,000 [38] 150,000 [12] | 0.004 ± 0.002 tp | 2.18 ± 0.021 tp | 0.762 ± 0.002 tp |
AT Cnc | 0.201 ± 0.0006 [26] | 0.9 ± 0.5 [26,29] | 0.47 ± 0.05 [29] | 0.52 ± 0.08 [29] | 13,500 ± 100 [39] 40,000 ± 170 [40] | 0.005 ± 0.003 tp | 1.58 ± 0.031 tp | 0.451 ± 0.001 tp |
4.2. Effective Temperature Profiles of the Accretion Discs
5. Discussion
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Object/ Values | Outbursts (Pre-Standstill) | Standstill | ||||
---|---|---|---|---|---|---|
B − V_max | (B − V)0_max | (Tcol)0_max | B − V_max | (B − V)0_max | (Tcol)0_max | |
JD 2458215.62803 | JD 2458975.6455–2458975.64692 | |||||
Z Cam | −0.09 ± 0.03 | −0.113 ± 0.04 | 11,800 ± 900 | 0.04 ± 0.02 | 0.024 ± 0.02 | 9800 ± 700 K |
JD 2458117.06694 | JD 2458209.66426–2458209.66597 | |||||
AT Cnc | 0.04 ± 0.03 | 0.037 ± 0.03 | 9700 ± 500 K | 0.13 ± 0.03 | 0.126 ± 0.03 | 8800 ± 400 K |
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Boneva, D.; Yankova, K.; Rusev, D. Periods of Outbursts and Standstills and Variations in Parameters of Two Z Cam Stars: Z Cam and AT Cnc. Astronomy 2024, 3, 208-219. https://doi.org/10.3390/astronomy3030013
Boneva D, Yankova K, Rusev D. Periods of Outbursts and Standstills and Variations in Parameters of Two Z Cam Stars: Z Cam and AT Cnc. Astronomy. 2024; 3(3):208-219. https://doi.org/10.3390/astronomy3030013
Chicago/Turabian StyleBoneva, Daniela, Krasimira Yankova, and Denislav Rusev. 2024. "Periods of Outbursts and Standstills and Variations in Parameters of Two Z Cam Stars: Z Cam and AT Cnc" Astronomy 3, no. 3: 208-219. https://doi.org/10.3390/astronomy3030013
APA StyleBoneva, D., Yankova, K., & Rusev, D. (2024). Periods of Outbursts and Standstills and Variations in Parameters of Two Z Cam Stars: Z Cam and AT Cnc. Astronomy, 3(3), 208-219. https://doi.org/10.3390/astronomy3030013