History and Developments in Astronomy

Abstract A new catalogue of eclipsing binary stars with eccentric orbits is presented. The catalogue lists the physical parameters (including apsidal motion parameters) of 124 eclipsing binaries with eccentric orbits. In addition, the catalogue also contains a list of 150 candidate systems, about which not much is kno…

• İBRAHİM BULUT

Here we analyze solar activity by focusing on time variations of the number of sunspot groups (SGs) as a function of their modified Zurich class. We analyzed data for solar cycles 20–23 by using Rome (cycles 20 and 21) and Learmonth Solar Observatory (cycles 22 and 23) SG numbers. All SGs recorded during these time in…

• ALİ KILÇIK

Abstract We have taken 88 dwarfs, covering the colour-index interval 0.37 ≤ (B–V)0 ≤ 1.07 mag, with metallicities –2.70 ≤ [Fe/H] ≤ +0.26 dex, from three different sources for new metallicity calibration. The catalogue of Cayrel de Stroble et al. (2001), which includes 65% of the stars in our sample, supplies detailed…

• SERAP AK
• YÜKSEL KARATAŞ

Abstract We have taken 88 dwarfs, covering the colour-index interval 0.37 ≤ (B–V)0 ≤ 1.07 mag, with metallicities –2.70 ≤ [Fe/H] ≤ +0.26 dex, from three different sources for new metallicity calibration. The catalogue of Cayrel de Stroble et al. (2001), which includes 65% of the stars in our sample, supplies detailed…

• SELÇUK BİLİR

We present in this paper the results from a multisite photometric campaign devoted to the γ Dor variable HD 164615. During the campaign data were collected in the Johnson and Strömgren photometric systems. A first search for sinusoidal periodicities yielded a three-term solution with frequencies f1 = 1.2328, f2 = 1.08…

• VAROL KESKİN

Binary systems showing both apsidal motion and light travel time (LTT) effects which cause orbital period changes in close binaries were studied. 15 triple systems showing apsidal motion were found by searching the literature, and a table including the important parameters of these systems was constructed. Six of the…

• ZEYNEP BOZKURT

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• VAROL KESKİN

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• TUNCAY ÖZDEMİR

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• İBRAHİM KÜÇÜK

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• TANSEL AK

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• NAZIM AKSAKER

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• VOLKAN BAKIŞ