Search Publications
Early-type W UMa contact binary system: New data on V535 Ara
Özkardeş, B.; Erdem, A.
This paper presents the results of spectroscopic and photometric observations of the early-type W UMa system V535 Ara. New high-resolution spectra were taken at the Mt. John University Observatory in 2007. Radial velocities and spectroscopic orbital elements of the system were determined by applying KOREL spectral disentangling. The resulting orbi…
A critical analysis of three near-infrared photometric methods of estimating distances to cataclysmic variables
Gariety, Michael J.; Ringwald, F. A.
A critical analysis of three methods of estimating distances to cataclysmic variables (CVs) is performed. These methods, by Ak et al., Beuermann, and Knigge, all use near-infrared ( JHK or Ks) magnitudes and the Barnes-Evans relation. We compare all three methods to distances measured by trigonometric parallax by Thorstensen, with Hubbl…
The XMM-Newton slew view of IGRJ17361-4441: A transient in the globular cluster NGC 6388
Read, A. M.; Nucita, A. A.; De Paolis, F. +1 more
IGRJ17361-4441 is a hard transient recently observed by the INTEGRAL satellite. The source, close to the center of gravity of the globular cluster NGC 6388, quickly became the target of follow-up observations conducted by the Chandra, Swift/XRT and RXTE observatories. Here, we concentrate in particular on a set of observations conducted by the XMM…
Stellar contents and star formation in the young cluster Stock 18
Pandey, J. C.; Sagar, Ram; Bhatt, Himali
We have carried out deep (V ∼ 21 mag) UBVRI photometric study of the star cluster Stock 18. These along with archival Infrared data have been used to derive the basic cluster parameters and also to study the star formation processes in and around the cluster region. The distance to the cluster is derived as 2.8 ± 0.2 kpc while its age is estimated…
Running waves observed by Hinode
Liang, H. F.; Yang, W. G.; Ma, L. +1 more
High cadence (up to 9.6 s) intensity images of a sunspot within the active region NOAA 10953 were obtained by the SOT onboard Hinode with the line H α 6563 Å on April 30, 2007. The running difference images show that running waves periodically appear within the sunspot umbra and propagate outward forming full circles or partial arcs. The propagati…
New eccentric eclipsing binary in triple system: SY Phe
Zasche, P.
Analyzing available photometry from Hipparcos, ASAS, Pi of the sky and Super WASP, we found that the system SY Phe is a detached eclipsing binary with similar components and orbital period about 5.27089 days. It has a slightly eccentric orbit, however the apsidal motion is probably very slow. The system undergoes an additional photometric variatio…
Absolute properties of the neglected eclipsing B-type binary HD 194495
Çakırlı, Ömür; Dervişoğlu, Ahmet; Sipahi, Esin +1 more
We present the results of the high-resolution spectroscopic observations of the neglected binary system HD 194495 (B3 IV-V+B4 V). A combined analysis of three different photometric data set ( Tycho B T and V T photometry, H p-band data of Hipparcos and V-band data of ASAS3 photometry) and radial velocities indicate…
Archival HST study of novae. I. The Seyfert galaxy NGC 3627
Alis, S.; Saygaç, A. T.
A V-band nova search was carried out in NGC 3627 with archival Hubble Space Telescope WFPC2 data which was obtained in the period between November 1997 and January 1998. A total of four novae candidates were discovered which corresponds to a global nova rate of R = 83.65 ± 7.58 yr -1. Taking into account the K-band luminosity obtained f…
Neglected reverse Algol system: WZ Hor
Erdem, A.; Sürgit, D.
This paper presents the first analysis of spectroscopic and photometric observations of the eclipsing binary star WZ Hor. Observations of the system were made at the Mt. John University Observatory in 2007. Since the light contribution of the secondary component was merely 2-3% of the total light of the system in the optical wavelengths, the radia…