Rotational evolution of the Sun

Kızıloğlu, N.
The evolutionary behaviour of rotating solar models with different initial angular-momentum distributions has been investigated through the pre-Main-Sequence and Main-Sequence phases. The angular momentum was removed from the convective envelope of the solar models according to the Kawaler's model of magnetic stellar wind (Kawaler, 1988). The models show that (i) the surface rotational velocities of the solar mass stars are independent of initial angular momentum for ages greater than 10(8) years and (ii) it is not possible to explain the neutrino problem and the sufficient depletion of lithium in the Sun.
Astrophysics and Space Science


Rotational evolution of intermediate mass stars with OPAL opacities: Mass of the convective core
Kiziloglu, N; Civelek, R (1996-03-01)
Theoretical evolutionary models for intermediate mass rotating stars were obtained by the use of OPAL opacities to see the effect on the internal structure and primarily on the mass of the convective core. The new ZAMS positions of rotating intermediate mass stars in the HR diagram were found to be above those of rotating stars obtained by using Cox & Stewart opacities. Rotation led to a reduction in the central value of the radiative temperature gradient and hence the masses of convective cores on the ZAMS...
Pre-Main-Sequence evolution of rotating low-mass stars
Kızıloğlu, Nilgün (Springer Science and Business Media LLC, 1989-4)
The evolutionary behaviour of rotating low-mass stars in the mass range 0.2 and 0.9M ⊙ has been investigated during the pre-Main-Sequence phase. The angular momentum is conserved locally in radiative regions and totally in convective regions, according to a predetermined angular velocity distribution depending on the structure of the star. As the stars contract toward the zero-age Main Sequence, they spin up under the assumption that the angular momentum is conserved during the evolution of the stars. When ...
Radial and nonradial oscillations of 44 Tauri
Civelek, R; Kiziloglu, N; Kirbiyik, H (American Astronomical Society, 2001-10-01)
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 d...
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...
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.
Citation Formats
N. Kızıloğlu, “Rotational evolution of the Sun,” Astrophysics and Space Science, pp. 83–89, 1992, Accessed: 00, 2020. [Online]. Available: