Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue
In our present work, we studied the photometric characteristics (core radius, limiting radius, reddening... etc.) as well as their dynamical state of the two newly discovered open clusters, SAI 24 and SAI 94. We investigated their photometric properties in the J, H, and Ks bands with the PP...
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doaj-3c0e5ec18c6f4342a3933cb666e739042020-11-25T01:40:07ZengAstronomical Observatory, Department of Astronomy, BelgradeSerbian Astronomical Journal1450-698X1820-92892019-01-012019198455310.2298/SAJ1998045E1450-698X1998045EPhotometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogueElsanhoury W.H.0Amin Magdy Y.1Astronomy Dept., National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Cairo, Egypt + Physics Dept., Faculty of Science, Northern Border University, Rafha Branch, Saudi ArabiaAstronomy, Space Science and Meteorology Dept., Cairo University, Cairo, EgyptIn our present work, we studied the photometric characteristics (core radius, limiting radius, reddening... etc.) as well as their dynamical state of the two newly discovered open clusters, SAI 24 and SAI 94. We investigated their photometric properties in the J, H, and Ks bands with the PPMXL catalogue. A method of separating open cluster stars from those belonging to the stellar background has been employed. The results of our calculations indicate that the numbers of probable members in SAI 24 and SAI 94 are 202 and 199, respectively. We have estimated the cluster center for SAI 24, i.e. α2000 = 02h 59m 26 .s36 and δ2000 = 60° 33' 02.''50 and for SAI 94 is α2000 = 08h 10m 16 .s36, δ2000 = −46° 17' 07.''91. The core radii rcore for SAI 24 and SAI 94 are found to be (1.92 ± 0.38) arcmin and (1.22 ± 0.10) arcmin, respectively and in the same manner the limiting radii rlim are about (2.45 ± 0.64) and (3.07 ± 0.57) arcmin. From the color-magnitude diagram, in view of the approximate logarithmic ages for SAI 24 and SAI 94 of 7.20 ± 0.20 and 9.10 ± 0.05, their distances are estimated to be (930 ± 30) pc and (3515 ± 60) pc, respectively. Also, we have calculated their projected distances (X⨀ and Y⨀) to the Galactic plane and the projected distance Z⨀ from the Galactic plane. The luminosity and mass functions of SAI 24 and SAI 94 clusters were outlined; accordingly, the masses were calculated to be (285 ± 17) M⨀ and (317 ± 18) M⨀, respectively. Finally, we concluded that these two clusters are dynamically relaxed according to our estimation of their dynamical evolution parameter τ as a function of their crossing time Tcross. The evaporation time τev as a function of their relaxation time Trelax is about 6.18 Myr and 25.38 Myr for SAI 24 and SAI 94, respectively.http://www.doiserbia.nb.rs/img/doi/1450-698X/2019/1450-698X1998045E.pdfTechniques: photometricOpen clusters and associations: individual: SAI 24, SAI 94 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Elsanhoury W.H. Amin Magdy Y. |
spellingShingle |
Elsanhoury W.H. Amin Magdy Y. Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue Serbian Astronomical Journal Techniques: photometric Open clusters and associations: individual: SAI 24, SAI 94 |
author_facet |
Elsanhoury W.H. Amin Magdy Y. |
author_sort |
Elsanhoury W.H. |
title |
Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue |
title_short |
Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue |
title_full |
Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue |
title_fullStr |
Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue |
title_full_unstemmed |
Photometric analysis of newly discovered open clusters SAI 24 and SAI 94 based on PPMXL catalogue |
title_sort |
photometric analysis of newly discovered open clusters sai 24 and sai 94 based on ppmxl catalogue |
publisher |
Astronomical Observatory, Department of Astronomy, Belgrade |
series |
Serbian Astronomical Journal |
issn |
1450-698X 1820-9289 |
publishDate |
2019-01-01 |
description |
In our present work, we studied the photometric characteristics (core radius,
limiting radius, reddening... etc.) as well as their dynamical state of
the two newly discovered open clusters, SAI 24 and SAI 94. We investigated
their photometric properties in the J, H, and Ks bands with the PPMXL
catalogue. A method of separating open cluster stars from those belonging to
the stellar background has been employed. The results of our calculations
indicate that the numbers of probable members in SAI 24 and SAI 94 are 202
and 199, respectively. We have estimated the cluster center for SAI 24, i.e.
α2000 = 02h 59m 26 .s36 and δ2000 = 60° 33' 02.''50 and for SAI 94 is α2000
= 08h 10m 16 .s36, δ2000 = −46° 17' 07.''91. The core radii rcore for SAI
24 and SAI 94 are found to be (1.92 ± 0.38) arcmin and (1.22 ± 0.10) arcmin,
respectively and in the same manner the limiting radii rlim are about (2.45
± 0.64) and (3.07 ± 0.57) arcmin. From the color-magnitude diagram, in view
of the approximate logarithmic ages for SAI 24 and SAI 94 of 7.20 ± 0.20 and
9.10 ± 0.05, their distances are estimated to be (930 ± 30) pc and (3515 ±
60) pc, respectively. Also, we have calculated their projected distances (X⨀
and Y⨀) to the Galactic plane and the projected distance Z⨀ from the
Galactic plane. The luminosity and mass functions of SAI 24 and SAI 94
clusters were outlined; accordingly, the masses were calculated to be (285 ±
17) M⨀ and (317 ± 18) M⨀, respectively. Finally, we concluded that these two
clusters are dynamically relaxed according to our estimation of their
dynamical evolution parameter τ as a function of their crossing time Tcross.
The evaporation time τev as a function of their relaxation time Trelax is
about 6.18 Myr and 25.38 Myr for SAI 24 and SAI 94, respectively. |
topic |
Techniques: photometric Open clusters and associations: individual: SAI 24, SAI 94 |
url |
http://www.doiserbia.nb.rs/img/doi/1450-698X/2019/1450-698X1998045E.pdf |
work_keys_str_mv |
AT elsanhourywh photometricanalysisofnewlydiscoveredopenclusterssai24andsai94basedonppmxlcatalogue AT aminmagdyy photometricanalysisofnewlydiscoveredopenclusterssai24andsai94basedonppmxlcatalogue |
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1725047024940744704 |