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Öğe High Resolution Coude Echelle Spectroscopy of IX Per(Amer Inst Physics, 2009) Ak, N. Filiz; Eker, Z.; Ak, H.; Kuecuek, I.High resolution (R=45033) Coude - Echelle spectra of IX Per has been obtained at TUBITAK National Observatory (TUG) of Turkey. IX Per has been known to be a single lined (SBI) spectroscopic binary having chromospheric activity. However, analyzed spectra of IX Per by KOREL disentangling method indicated that the system is a double lined (SB2) spectroscopic binary. Weaker lines from the secondary arc discovered on the decomposed spectra. A preliminary orbit indicates that the mass ratio of the system is 0.64. The light contribution of the secondary is tip to 10% in investigated spectral region. Circular orbit is sufficient to explain radial velocity variations.Öğe New findings supporting the presence of a thick disc and bipolar jets in the ? Lyrae system(Edp Sciences S A, 2007) Ak, H.; Chadima, P.; Harmanec, P.; Demircan, O.; Yang, S.; Koubsky, P.; Skoda, P.Context. Understanding large-scale mass exchange in binaries also requires studies of complicated objects in the rapid phases of the process. beta Lyr is one such object. Aims. Our goals were to analyse 52 photographic and 651 electronic spectra of beta Lyr to obtain additional information about circumstellar matter and to investigate spectrophotometric information for the first time. Methods. Improved quadratic ephemeris was derived via orbital solution with the FOTEL program. The spectra were disentangled using the KOREL program. Spectrophotometric quantities of 15 stronger absorption lines of the primary were measured and corrected for the orbital continuum variations using the fluxes calculated from a fit of the light curves with the BINSYN program. Central intensities of the V and R peaks of the Ha emission line were measured and corrected for the orbital light changes using the R-band light curve numerically modelled with the program PERIOD04. Results. Disentangling of photographic and electronic spectra led to the detection of weak absorption lines originating from the pseudophotosphere of the accretion disc. This way, a rich line spectrum of the accretion disc, not limited to only two previously known Si II 6347 and Si II 6371 lines, was obtained. A projected rotational velocity of 180 km s(-1) was estimated for the disc spectrum. Such a value agrees well with the assumption of the Keplerian rotation of the outer layers of the accretion disc. After the correction, a pronounced increase of the strength of all absorption lines around phases of the primary eclipse was found. We argue that this is due to additional absorption of the light of the primary in one of the jets and/or scattering envelope above the accretion disc of the gainer. The net intensity of the V peak of Ha shows no orbital variation, but a possible 271-d periodicity. The net intensity of the R peak shows mild orbital changes and a slow change over a cycle of about 2780 days. These results seem to support the earlier conclusion that the Ha emission originates in the jet-like structures. Conclusions. All new findings support the current picture that the circumstellar structures of beta Lyr consist of a thick accretion disc, bipolar jets, and a scattering envelope above the disc.Öğe New findings supporting the presence of several distinct structures of circumstellar matter in ? Lyræ(2006) Chadima, P.; Harmanec, P.; Ak, H.; Demirçan, O.; Yang, S.; Koubsk?, P.; Škoda, P.(1) 52 photographic and 651 electronic spectra were disentangled using the program KOREL. This led to the detection of a number of weak absorption lines originating in the atmosphere of the accretion disk. So far, the detection of this disk spectrum was only reported for the Si 6347 and 6371 doublet. (2) The basic spectrophotometric quantities of 15 absorption lines of the primary were measured and corrected for the orbital light changes in order to eliminate the contribution of the secondary light to the observed continuum level. After the correction, a significant phase dependency of the spectral-line characteristics near the primary eclipse was detected. In all probability, another so far unknown absorption-line spectrum was thus found. This spectrum may be due to additional absorption of light of the primary in one of the jet-like structures and in the spherical gas envelope surrounding the accretion disk. Both these structures are seen projected against the primary during its eclipse. © 2007 International Astronomical Union.Öğe Personality traits in fibromyalgia patients with paresthetic complaints(Wiley, 2016) Balbaloglu, O.; Tanik, N.; Alpayci, M.; Ak, H.; Karaahmet, E.; Inan, L. E.[Anstract Not Available]
