A5088906220- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Astronomy and Astrophysical Research
- High-pressure geophysics and materials
- Astrophysics and Cosmic Phenomena
- Computational Physics and Python Applications
- Advanced Fiber Optic Sensors
- Geomagnetism and Paleomagnetism Studies
- Magnetic confinement fusion research
- Tropical and Extratropical Cyclones Research
- Astro and Planetary Science
- Atomic and Molecular Physics
- SAS software applications and methods
Ege University
2007-2024
Astronomy and Space
2024
Çanakkale Onsekiz Mart Üniversitesi
2022
Max Planck Institute for Extraterrestrial Physics
2018
Context. The paper is comprised of optical identification and multiwavelength studies a new X-ray source discovered by the Spectrum Roentgen-Gamma (SRG) observatory during ART-XC survey its follow-up observations. Aims. We aim to identify SRGA J213151.5+491400 in wavelengths. determine spectra light curves high low states find periodicities resolve emission lines system using ground-based data. intend study spectral temporal characteristics SRG surveys NICER data state. Methods. present from...
This paper is the second in planned series of investigations. We present new radial velocities and photometric observations V2080 Cyg V2365 Oph. New UBV data were analysed for systems' parameters. While consists two nearly equal F-type main-sequence stars, Oph has different components, namely an early A-type primary a G-type secondary star. ephemerides are calculated both systems. The masses component stars have been derived as 1.19 ± 0.02 1.16 M⊙ 1.97 1.06 0.01 effective temperatures...
We present the first radial velocities and ground-based photometric observations of V1665 Aql AG Ari. These double-lined eclipsing binaries have eccentric orbits with eccentricities 0.24 0.09, respectively. New UBV data were analysed using a modified version Wilson–Devinney program for parameters systems. Good phase coverage relatively small scatter both in light radial-velocity curves meant that eccentricity argument periastron as well orbital stellar could be determined. Our solutions...
We present new radial velocities and UBV photometric observations of three eclipsing binaries, V799 Cas, BX Psc HD 172189, in order to increase the number close binaries with absolute parameters determined accurately. Standard wide-band indices for systems comparison stars were Using times mid-eclipses, ephemerides are calculated systems. Cas 172189 consist two well-detached components eccentric orbits. is a single-lined binary which consists late-A an early-K star. The effective...
We present new radial velocities and photometric observations of three double-lined eclipsing binaries LL Aqr, MP Del NSV 20913. This paper is the third in planned series investigations. Standard wide-band indices for systems comparison stars were determined accurately. Using times mid-eclipses, ephemerides are calculated systems. These consist two well-detached components eccentric orbits. The effective temperatures hotter reddening have been estimated from Johnson UBV calibrations. New...
This paper presents a new model of North Polar Coronal Hole (NPCH) to study dissipation/propagation MHD waves. We investigate the effects isotropic viscosity and heat conduction on propagation characteristics waves in NPCH. first NPCH by considering differences radial as well direction perpendicular line sight (\textit{los}) temperature, particle number density non-thermal velocities between plumes interplume lanes for specific case \ion{O}{VI} ions. includes parallel (to magnetic field)...
XY Ari is one of the few known eclipsing intermediate polars. We present results from a detailed analysis an unpublished archival observation using XMM–Newton EPIC pn and MOS data in quiescent state Ari. The X-ray orbital modulation spin-pulse variations were investigated for energy-dependent modulations different energy bands. broad observed with various observations was confirmed hard (>1.6 keV). light curves folded at spin phases show double-peak profile, as expected two-pole accretion....
We report results of optical identification and multi-wavelength study a new polar-type magnetic cataclysmic variable (MCV), SRGA J213151.5+491400, discovered by Spectrum Roentgen-Gamma ($SRG$) observatory in the course all-sky survey. present data from telescopes Turkey (RTT-150 T100 at T\"UBITAK National Observatory), Russia (6-m 1-m SAO RAS), together with X-ray obtained $ART-XC$ $eROSITA$ aboard $SRG$ $NICER$ observatory. detect J213151.5+491400 high state 2020 (17.9 mag) that decreases...
This study aims at timing the eclipses of binary star TU UMi.The times minima are taken from literature, our observations in April 2004 and TESS between 2019 2022.The orbital period analysis system indicates that there is a cyclic oscillation with an amplitude 0.0081d 9.03 yr, accompanied by continuous decrease rate dP/dt = -1.12× 10 -7 d yr -1 .We secular evolution possibility existence third companion or magnetic activity cycle primary component system.
This paper presents a new model of North Polar Coronal Hole (NPCH) to study dissipation/propagation MHD waves. We investigate the effects isotropic viscosity and heat conduction on propagation characteristics waves in NPCH. first NPCH by considering differences radial as well direction perpendicular line sight (\textit{los}) temperature, particle number density non-thermal velocities between plumes interplume lanes for specific case \ion{O}{VI} ions. includes parallel (to magnetic field)...
Observations in the Solar North Polar Coronal Hole (NPCH) show that this region has high temperature values (10^6-10^8 K). At temperature, coronal plasma loses energy to transition below through heat conduction and optically thin emission. It is still a matter of debate how replace lost solar corona maintain observed values. In study, we aimed study wave theory, which an important model proposed for heating problem NPCH. We assumed based on Alfvén/ion cyclotron resonance process with O VI...
SRGA J021303.5+604536, Ocak 2021’de TUG-KFU-IKI arasındaki protokole göre paylaşılan yeni ART-XC kaynaklarından biridir. 20210313–20221019 tarihleri arasında gözlendi. Toplamda yaklaşık 1.5 yıla yayılan 17 gece boyunca bu parlak (yaklaşık 11 kadir) kaynağın RTT150 ile 127 adet tayfı alınmıştır. Kaynağın tayf sürekliliği kırmızı olduğu gibi düz özelliği de var, hidrojenin Balmer çizgileri (şiddetli H-alfa, H-beta ve zayıf H-gama), Ca II üçlüsü (8500, 8544 8664 A) O I (8446 emisyondadır....
XY Ari is one of the few known eclipsing intermediate polars. We present results from a detailed analysis an unpublished archival observation using XMM-Newton EPIC pn and MOS data in quiescent state Ari. The X-ray orbital modulation spin pulse variations were investigated for energy dependent modulations different bands. broad observed with various observations was confirmed at hard (>1.6 keV). light curves folded phases show double peak profile as expected two pole accretion. found to be...
Bileşenler arası madde transferinin gözlemlendiği ($10^{-11} - 10^{-9} M_{\odot}$/yıl) kataklismik değişen yıldızların (CV) uzun dönemli evrimi, yörünge açısal momentumunun kaybedilmesi ile sürdürülür ve bu süreç çiftin döneminde de önemli değişimlere yol açtığı gözlemlenmiştir. CV'lerin gözlemsel dönem dağılımlarının açıklamaya dayanan standart CV evrim modellerinde en çok kabul gören bozulmuş manyetik frenleme modeli momentum kaybındaki ani değişimleri, kırmızı cüce bileşenin kütle...