125 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Northern Border UniversitySA30 papers
- Centre National de la Recherche ScientifiqueFR16 papers
- Taibah UniversitySA16 papers
- Cairo UniversityEG12 papers
- Instituto de Astrofísica de AndalucíaES11 papers
- Université Paris CitéFR11 papers
- Astrophysique, Instrumentation et ModélisationFR10 papers
- Commissariat à l'Énergie Atomique et aux Énergies AlternativesFR10 papers
- Leibniz Institute for Astrophysics PotsdamDE10 papers
- Sorbonne UniversitéFR10 papers
- Astronomical ObservatoryRS9 papers
- CEA Paris-SaclayFR9 papers
21 papers · 1 filter
An Investigation of 11 previously unstudied open star clusters
A. L. Tadross
The main astrophysical properties of 11 previously unstudied open star clusters are probed with JHK Near-IR (2MASS) photometry of Cutri et al. [Cutri, R., et al., 2003. The IRSA 2M…
Soft X-ray spectral variability of AM Herculis
K. Beuermann, E. El Kholy, K. Reinsch
Polars (AM Herculis binaries) are a prominent class of bright soft X-ray sources, many of which were discovered with ROSAT. We present a homogenous analysis of all the pointed ROSA…
A Reinvestigation of the Physical Properties of Pismis 3 based on 2MASS Photometry
A. L. Tadross
As a continuation of a series of work, we aim to refine and re-determine the physical parameters of previously rarely or un-studied open star clusters with good quality CMDs using…
The inner structure of the S0 galaxy NGC3384
H. Meusinger, H. A. Ismail, P. Notni
We re-investigate the lenticular galaxy NGC 3384, a member of the LeoI galaxy group, using HST and multi-colour Calar Alto observations. Various approaches are used to visualize th…
Rate of Period Change as a Diagnostic of Cepheid Properties
David G. Turner, Mohamed Abdel-Sabour Abdel-Latif, Leonid N. Berdnikov
Rate of period change for a Cepheid is shown to be a parameter that is capable of indicating the instability strip crossing mode for individual objects, and, in conjuncti…
Observations of H-alpha, iron, and oxygen lines in B, Be, and shell stars
S. M. Saad, J. Kubat, D. Korcakova +8
We have carried out a spectroscopic survey of several B, Be, and shell stars in optical and near-infrared regions. Line profiles of the H-alpha line and of selected Fe II and O I l…
Indirect evidence for short period magnetic cycles in W UMa stars
T. Borkovits, M. M. Elkhateeb, Sz. Csizmadia +4
Complex period variations of five W UMa type binaries (AB And, OO Aql, DK Cyg, V566 Oph, U Peg) were investigated by analyzing their O--C diagrams, and several common features were…
The Growth of the Local Void and the Origin of the Local Velocity Anomaly
I. Iwata, K. Ohta, K. Nakanishi +2
The Local Void is the nearest void from us and is thought to be playing an important role in the kinematics of the local universe, especially as one of the suspected source of the…
The fundamental plane of isolated early-type galaxies
Fatma M. Reda, Duncan A. Forbes, George K. T. Hau
Here we present new measurements of effective radii, surface brightnesses and internal velocity dispersions for 23 isolated early-type galaxies. The photometric properties are deri…
Properties and nature of Be stars XXIII. Long-term variations and physical properties of kappa Dra
S. M. Saad, J. Kubat, P. Koubsky +9
We present an analysis of new spectroscopic observations of the bright Be star kappa Dra obtained at the Ondrejov observatory during 1992 - 2003 and UBV photometric observations se…
New analysis in the field of open cluster Collinder 223
A. L. Tadross
The present study of the open cluster Collinder 223 (Cr 223) has been mainly depended on the photoelectric data of Claria & Lapasset (1991; hereafter CL91). This data of CL91 has b…
Photometrical Review of Open Cluster M25
A. L. Tadross, A. I. Osman, M. A. Marie +2
The young open star cluster M25 (IC 4725) is located in the direction of the galactic center in a crowded region, near much irregular absorption features on Sagittarius arm. This c…
HII regions in the spiral galaxy NGC 3389
Hamed Abdel-Hamid, Sang-Gak Lee, Peter Notni
CCD observations in V, I and H for NGC 3389 are used to present photometry of 61 HII regions. Their and positions, diameters and their absolute luminosities have been d…
Clusters and Superclusters in the Sloan Digital Sky Survey
J. Einasto, G. H"utsi, M. Einasto +5
Two-dimensional high-resolution density field of galaxies of the Early Data Release of the Sloan Digital Sky Survey with a smoothing lengths 0.8 h^{-1} Mpc is applied to extract cl…
An optical and near IR study of the old open cluster NGC 2141
G. Carraro, S. Hassan, S. Ortolani +1
We report on CCD optical (B and V passbands) and near IR (J and K bands) observations in the region of the old open cluster NGC 2141. By combining the two sets of photometry (500 s…
Stellar Population analysis from Broad-Band Colours
Hamed Abdel-Hamid, Peter Notni
We have developed an analytical method to investigate the stellar populations in a galaxy using the broad-band colours. The method enables us to determine the relative contribution…
Surface photometry of NGC 3077
Hamed Abdel-Hamid, Peter Notni
We present surface photometry of the irregular galaxy NGC 3077 using two data sets: photographic plates and CCD images. Isophotal contours, luminosity and colour distributions as w…
Compact Groups of Galaxies in the Las Campanas Redshift Survey
S. S. Allam, D. L. Tucker
We have recently extracted a catalog of compact groups of galaxies (CGs) from the Las Campanas Redshift Survey. This catalog of Las Campanas Compact Groups (LCCGs) contains 76 CGs…
Loose Groups of Galaxies in the Las Campanas Redshift Survey
D. L. Tucker, A. Oemler, Y. Hashimoto +6
A ``friends-of-friends'' percolation algorithm has been used to extract a catalogue of dn/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Surv…
Star Formation in Las Campanas Compact Groups
Sahar S. Allam, Douglas L. Tucker, Huan Lin +1
Compact groups (CGs) of galaxies offer an exceptional laboratory for the study of dense galaxian environments --- where interactions, tidally induced activity, and mergers are expe…
Early versus late type galaxies in compact groups
A. A. Shaker, G. Longo, P. Merluzzi
We find a strong correlation between the effective radius of the largest early-type galaxies in compact groups of galaxies and the velocity dispersion of the groups. The lack of a…