Radial and nonradial oscillations of 44 Tauri

Download

index.pdf

Date

2001-10-01

Author

Civelek, R
Kiziloglu, N
Kirbiyik, H

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

146
views

0
downloads

Evolutionary stellar models of 44 Tauri, a multiperiodic delta Scuti star, have been developed theoretically and compared with earlier observational reports. The models depict 44 Tau at the hydrogen-shell-burning stage, when it is in radiative equilibrium with a very thin surface convective layer. Using the models, we performed calculations to obtain radial and nonradial adiabatic oscillation frequencies, and the equations were treated linearly. The results showed that the radial fundamental (6.899 cycles day(-1)) and first-overtone (8.961 cycles day(-1)) frequencies and the five nonradial modes of low harmonic degree that had been determined theoretically were in agreement with the observed values of previous authors to an accuracy of a few parts in 10(3). However, a difference emerged in the nonradial frequencies, which we classified as g-modes of low harmonic degree, whereas the observational reports had classified them as p-modes. In addition, even though 44 Tau has a rotation v sin i = 6.8 km s(-1) (according to Solano and Fernley), which we considered negligible, we analyzed the effect of rotation. Our findings revealed that rotation modulated the oscillation frequencies of the nonrotating model on the order of 10(-2).

Subject Keywords

Space and Planetary Science, Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/66296

Journal

ASTRONOMICAL JOURNAL

DOI

https://doi.org/10.1086/323078

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Pregalactic-primordial low-mass stars Kızıloğlu, Nilgün Gülşan; Eryurt, Dilhan Ezer (Springer Science and Business Media LLC, 1987-8) The Main-Sequence positions as well as the evolutionary behavior of Population III stars up to an evolution age of 2×1010 yr, taking this time as the age of the Universe, have been investigated in the mass range 0.2 and 0.8M ⊙. While Population III stars with masses greater than 0.3M ⊙ develop a radiative core during the approach to the Main Sequence, stars with masses smaller than 0.3M ⊙ reach the Main Sequence as a wholly convective stars. Population III stars with masses greater than 0.5M ⊙ show a bright...
Optical imaging and spectroscopic observation of the galactic supernova remnant G85.9-0.6 GÖK, FATMA; Sezer, A.; Aktekin, E.; Guever, T.; Ercan, N. (Springer Science and Business Media LLC, 2009-11-01) Optical CCD imaging with H alpha and [SII] filters and spectroscopic observations of the galactic supernova remnant G85.9-0.6 have been performed for the first time. The CCD image data are taken with the 1.5 m Russian-Turkish Telescope (RTT150) at TBA degrees TAK National Observatory (TUG) and spectral data are taken with the Bok 2.3 m telescope on Kitt Peak, AZ.
Modelling the oscillating star V1162 Ori Civelek, R; Kiziloglu, N; Kirbiyik, H (EDP Sciences, 2003-12-01) Evolutionary stellar models of V1162 Ori, with the latest observations of a multiperiodic delta Scuti star, have been calculated theoretically and compared with the observations. Theoretical models representative of the star indicate that it is at an advanced stage of its main-sequence evolution. Calculations have been made for two different masses, 1.80 and 1.82 M-., at different rotational speeds. Rotation was treated as a perturbation and only the first-order effect was considered. The evolutionary model...
Global Site Selection for Astronomy AKSAKER, NAZIM; Yerli, Sinan Kaan; Erdogan, M. A.; Kurt, Z.; Kaba, K.; Bayazit, M.; YEŞİLYAPRAK, Cahit (Oxford University Press (OUP), 2020-03-01) A global site selection for astronomy was performed with 1 km spatial resolution (similar to 1 gigapixel in size) using long-term and up-to-date datasets to classify the entire terrestrial surface of the Earth. Satellite instruments are used to get the following datasets of geographical information system (GIS) layers: cloud coverage, digital elevation model, artificial light, precipitable water vapour, aerosol optical depth, wind speed, and land use and land cover. A multi-criteria decision analysis (MCDA)...
Frequency-resolved spectroscopy of XB1323-619 using XMM-Newton data: detection of a reflection region in the disc Balman, Şölen (Oxford University Press (OUP), 2010-09-21) We present the frequency-resolved energy spectra (FRS) of the low-mass X-ray binary dipper XB1323-619 during persistent emission in four different frequency bands using an archival XMM-Newton observation. FRS method helps to probe the inner zones of an accretion disc. XB1323-619 is an Atoll source and a type-I burster. We find that the FRS is well described by a single blackbody component with kT in a range 1.0-1.4 keV responsible for the source variability in the frequency ranges of 0.002-0.04 and 0.07-0.3...

Citation Formats

R. Civelek, N. Kiziloglu, and H. Kirbiyik, “Radial and nonradial oscillations of 44 Tauri,” ASTRONOMICAL JOURNAL, pp. 2042–2046, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66296.