The Photometric Analysis and Classification of High Amplitude δ Scuti: AE Ursae Majoris

Authors

  • Yash Kheni Ahmedabad International School
  • Vedang Pandit

DOI:

https://doi.org/10.47611/jsrhs.v11i4.3070

Keywords:

Time series analysis, Fourier transforms, Delta Scuti, Variable stars, Astronomy, Astrophysics, Stellar Evolution

Abstract

AE UMa, a Population I high amplitude Delta Scuti (HADS), was observed for 4 nights through 14-21 March 2022. 454 Visual CMOS observations and 11 new times of maxima were obtained over a period of ~19.4 hours in total. Using python coding and Fourier analysis, a fundamental frequency ƒ0 = 11.6251 cd-1 was established and further observation of amplitudes of light maxima led to beat phenomenon period Pb = 0.29360 d. Subsequently, the first overtone frequency ƒ1 = 15.0316 cd-1 was calculated and the period ratio = 0.7734 was found to be relatively unchanged from Szeidl (1974). Thereafter, the period ratio-metallicity correlation determined by Hintz et al. (1997b) was used to estimate the metallicity [Fe/H] of AE UMa. I concluded that AE UMa is incorrectly classified as a Pop. II HADS (SX Phoenicis) and should be grouped with Pop. I HADS.    

Downloads

Download data is not yet available.

References or Bibliography

Szeidl, B. (1974). The Secondary Period of AE UMa. Information Bulletin on Variable Stars, 903.

Hintz, E. G., Joner, M. D., McNamara, D. H., Nelson, K. A., Moody, J. W., & Kim, C. (1997b). Time-Series Ensemble Photometry of SX Phoenicis Stars. I. BL Camelopardalis. Publications of the Astronomical Society of the Pacific, 109(731), 15. https://iopscience.iop.org/article/10.1086/133977

Campbell, W. W., & Wright, W. H. (1900). Stars with variable velocities. ApJ, 12, 254-257. https://ui.adsabs.harvard.edu/link_gateway/1900ApJ....12..254C/doi:10.1086/140765

Colacevich, A. (1935). The variable radial velocity of [delta] Scuti. Lick Observatory Bulletin, 17, 171-174. https://ui.adsabs.harvard.edu/link_gateway/1935PASP...47..231C/doi:10.1086/124599

Fath, E. A. (1935). A photometric study of Delta Scuti. Lick Observatory Bulletin, 479, 175-177. https://ui.adsabs.harvard.edu/link_gateway/1935LicOB..17..175F/doi:10.5479/ADS/bib/1935LicOB.17.175F

Baglin, A., Breger, M., Chevalier, C., Hauck, B., Le Contel, J. M., Sareyan, J. P., & Valtier, J. C. (1973). Delta Scuti stars. Astronomy and Astrophysics, 23, 221-240.

Breger, M. (2000). delta Scuti stars. In Delta Scuti and Related Stars (Vol. 210, p. 3).

Aerts, C., Christensen-Dalsgaard, J., & Kurtz, D. W. (2010). Asteroseismology. Springer Science & Business Media.

Geyer, E., Kippenhahn, R., & Strohmeier, W. (1955). Kleine Veröff. Remeis-Sternwarte Bamberg, (11).

Tsesevich, V. P. (1956). Var. Stars, 11, 125.

Filatov, G. S. (1960). On the unstudied variables stars in the BV-Lists. Astronomicheskij Tsirkulyar, 215, 20-22.

Götz, W., & Wenzel, W. (1961). Mitteilungen über Veränderliche Sterne.

Tsesevich, V. P. (1973). On the dwarf cepheid AE UMa. Astronomicheskij Tsirkulyar, 775, 2-4.

Broglia, P., & Conconi, P. (1975). Beat phenomena in the dwarf cepheid AE UMa. Astronomy and Astrophysics Supplement Series, 22, 243-261.

Garcia, J. R., Cebral, J. R., Scoccimarro, E. R., Wahnon, P., Arena, R., Bazterra, V., ... & Zimmermann, M. (1995). A catalogue of variable stars in the lower instability strip. Astronomy and Astrophysics Supplement Series, 109, 201-262.

Collins, K. A., Kielkopf, J. F., Stassun, K. G., & Hessman, F. V. (2017). AstroImageJ: image processing and photometric extraction for ultra-precise astronomical light curves. The Astronomical Journal, 153(2), 77. https://iopscience.iop.org/article/10.3847/1538-3881/153/2/77

Lomb, N. R. (1976). Least-squares frequency analysis of unequally spaced data. Astrophysics and space science, 39(2), 447-462. https://ui.adsabs.harvard.edu/link_gateway/1976Ap&SS..39..447L/doi:10.1007/BF00648343

Scargle, J. D. (1982). Studies in astronomical time series analysis. II-Statistical aspects of spectral analysis of unevenly spaced data. The Astrophysical Journal, 263, 835-853. https://ui.adsabs.harvard.edu/link_gateway/1982ApJ...263..835S/doi:10.1086/160554

Robitaille, T. P., Tollerud, E. J., Greenfield, P., Droettboom, M., Bray, E., Aldcroft, T., ... & Streicher, O. (2013). Astropy: A community Python package for astronomy. Astronomy & Astrophysics, 558, A33. https://doi.org/10.1051/0004-6361/201322068

Price-Whelan, A. M., Sipőcz, B. M., Günther, H. M., Lim, P. L., Crawford, S. M., Conseil, S., ... & Astropy Coordination Committee. (2018). The astropy project: building an open-science project and status of the v2. 0 core package. The Astronomical Journal, 156(3), 123. https://iopscience.iop.org/article/10.3847/1538-3881/aabc4f/meta

Niu, J. S., Fu, J. N., Li, Y., Yang, X. H., Zong, W., Xue, H. F., ... & Zuo, F. (2017). AE Ursae Majoris–a δ Scuti star in the Hertzsprung Gap. Monthly Notices of the Royal Astronomical Society, 467(3), 3122-3139. https://doi.org/10.1093/mnras/stx125

Coates, D. W., & Landes, H. (2008). The beat-curve approach applied to AE UMa. Communications in Asteroseismology, 153, 8-16.

Zhou, A. Y. (2001). Period and amplitude variations in the high-amplitude δ Scuti star AE Ursae Majoris. Astronomy & Astrophysics, 374(1), 235-242.

Niu, J. S., Fu, J. N., Yang, X. H., & Zong, W. K. (2013). Pulsations and Period Changes in the double-mode SX Phoenicis Star AE Ursae Majoris. arXiv preprint arXiv:1304.3772.

Cox, J. P. (2017). Theory of Stellar Pulsation. (PSA-2), Volume 2 (Vol. 31). Princeton University Press.

Hintz, E., Hintz, M. L., & Joner, M. D. (1997a). Time-Series Ensemble Photometry of SX Phoenicis Stars. II. AE Ursae Majoris. Publications of the Astronomical Society of the Pacific, 109(740), 1073. https://ui.adsabs.harvard.edu/link_gateway/1997PASP..109.1073H/doi:10.1086/133977

Published

11-30-2022

How to Cite

Kheni, Y., & Pandit, V. (2022). The Photometric Analysis and Classification of High Amplitude δ Scuti: AE Ursae Majoris. Journal of Student Research, 11(4). https://doi.org/10.47611/jsrhs.v11i4.3070

Issue

Section

HS Research Projects