Modelling the oscillating star V1162 Ori

Download
2003-12-01
Civelek, R
Kiziloglu, N
Kirbiyik, H
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 models were used to obtain the radial and non-radial adiabatic oscillation frequencies and the oscillation equations were treated linearly. The radial fundamental frequency (12.7082 d(-1)) named so by the observers and the other observed frequencies were theoretically found from the model ( model 4) that is claimed to represent the observed star the best. The agreement with the observations is within a few hundredths of a cycle or better. Since an observational rotational value of v sin i = 46 +/- 4 km s(-1) is published in the literature, rotational effects on the oscillation modes were also considered. It is shown that the oscillation frequencies increase with rotational speed for rotational velocities larger than about 50 km s(-1).
ASTRONOMY & ASTROPHYSICS

Suggestions

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...
OBSERVATIONS OF THE SHELL-TYPE SUPERNOVA REMNANT CASSIOPEIA A AT TeV ENERGIES WITH VERITAS
Acciari, V. A.; et. al. (IOP Publishing, 2010-05-01)
We report on observations of very high energy gamma rays from the shell-type supernova remnant (SNR) Cassiopeia A with the Very Energetic Radiation Imaging Telescope Array System stereoscopic array of four imaging atmospheric Cherenkov telescopes in Arizona. The total exposure time for these observations is 22 hr, accumulated between September and November of 2007. The gamma-ray source associated with the SNR Cassiopeia A was detected above 200 GeV with a statistical significance of 8.3 sigma. The estimated...
Upper limits to the SN1006 multi-TeV gamma-ray flux from HESS observations
Aharonian, F; et. al. (EDP Sciences, 2005-07-01)
Observations of the shell-type supernova remnant SN1006 have been carried out with the HESS system of Cherenkov telescopes during 2003 (18.2 h with two operating telescopes) and 2004 (6.3 h with all four telescopes). No evidence for TeV gamma-ray emission from any compact or extended region associated with the remnant is seen and resulting upper limits at the 99.9% confidence level are up to a factor 10 lower than previously-published fluxes from CANGAROO. For SN1006 at its current epoch of evolution we def...
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 ...
Early phases of different types of isolated neutron star
Ankay, A; Sahin, S; Karanfil, G; Yazgan, E (World Scientific Pub Co Pte Lt, 2005-06-01)
Two Galactic isolated strong X-ray pulsars seem to be in the densest environments compared to other types of Galactic pulsar. X-ray pulsar J1846-0258 can be in an early phase of anomalous X-ray pulsars and soft gamma repeaters if its average braking index is similar to 1.8-2.0. X-ray pulsar J1811-1925 must have a very large average braking index (similar to 11) if this pulsar was formed by SN 386AD. This X-ray pulsar can be in an early phase of the evolution of the radio pulsars located in the region P simi...
Citation Formats
R. Civelek, N. Kiziloglu, and H. Kirbiyik, “Modelling the oscillating star V1162 Ori,” ASTRONOMY & ASTROPHYSICS, pp. 503–507, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66454.