The Young Open Cluster NGC 2384

International Astronomical Union Colloquium ◽

10.1017/s0252921100106773 ◽

1984 ◽

Vol 78 ◽

pp. 295-299

Author(s):

S.M. Hassan

Keyword(s):

Spectral Type ◽

Open Cluster ◽

Apparent Distance ◽

Distance Modulus ◽

Colour Excess ◽

Young Open Cluster ◽

Ubv Photometry ◽

Spiral Arm

AbstractCombined photoelectric – photographic UBV-photometry for NGC 2384 is discussed. The results achieved so far are summarized and indicate that this cluster is young enough to be used as spiral arm tracer out to a distance of 3.27 kpc. The colour excess E(B-V) is 0.31, the apparent distance modulus is 13m.50 and its earliest spectral type is BO.

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IC 361, a distant intermediate-age cluster in Camelopardalis

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309992080 ◽

2009 ◽

Vol 5 (S266) ◽

pp. 557-560

Author(s):

Justas Zdanavičius ◽

Richard P. Boyle ◽

Frederick J. Vrba ◽

Kazimieras Zdanavičius ◽

Stanislava Bartašiūtė

Keyword(s):

Open Cluster ◽

Interstellar Extinction ◽

Distance Modulus ◽

Ccd Photometry ◽

True Distance ◽

Individual Stars ◽

Cluster Distance ◽

Spiral Arm

AbstractWe have undertaken CCD photometry in the eight-color Vilnius + I system for the open cluster IC 361 (l = 147.5°, b = 5.7°) located in the constellation of Camelopardalis. Based on multicolor data, estimates of distance moduli, foreground reddening and metallicity have been obtained for individual stars measured in the field of the cluster. This allowed us to eliminate most of the field stars and to identify the probable cluster members, from which we derived the true distance modulus (m − M)0 = 12.7 mag and metallicity [Fe/H] = −0.3 dex. The interstellar extinction is found to be nonuniform across the field, with values of AV ranging from 1.9 to 2.6 mag. A comparison of the color–magnitude diagrams with Padova isochrones yields (m − M)0 = 12.6 mag, or a cluster distance of 3.3 kpc, and an age of 1.0 Gyr. Therefore, IC 361 appears to be a mildly metal-deficient cluster of intermediate age, located as far as, or just beyond, the Perseus spiral arm.

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Pseudo-photometric distances of 30 open clusters

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833082 ◽

2018 ◽

Vol 619 ◽

pp. A132 ◽

Cited By ~ 1

Author(s):

A. Chelli ◽

G. Duvert

Keyword(s):

Spectral Type ◽

Large Scale ◽

Open Cluster ◽

Estimation Method ◽

Distance Estimation ◽

Open Clusters ◽

Distance Modulus ◽

Stellar Clusters ◽

The Mean ◽

The Difference

Aims. We demonstrate that reliable photometric distances of stellar clusters, and more generally of stars, can be obtained using pseudomagnitudes and rough spectral type without having to correct for visual absorption. Methods. We determine the mean absolute pseudomagnitude of all spectral (sub)types between B and K. Distances are computed from the difference between the star’s observed pseudomagnitude and its spectral type’s absolute pseudomagnitude. We compare the distances of 30 open clusters thus derived against the distances derived from TGAS parallaxes. Results. Our computed distances, up to distance modulus 12, agree within 0.1 mag rms with those obtained from TGAS parallaxes, proving excellent distance estimates. We show additionally that there are actually two markedly different distances in the cluster NGC 2264. Conclusions. We suggest that the pseudomagnitude distance estimation method, which is easy to perform, can be routinely used in all large-scale surveys where statistical distances on a set of stars, such as an open cluster, are required.

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CCD UBV Photometry of the Young Open Cluster NGC 3766

The Astronomical Journal ◽

10.1086/118349 ◽

1997 ◽

Vol 113 ◽

pp. 1359 ◽

Cited By ~ 17

Author(s):

Andre Moitinho ◽

Emilio J. Alfaro ◽

Joao Lin Yun ◽

Randy L. Phelps

Keyword(s):

Open Cluster ◽

Young Open Cluster ◽

Ubv Photometry

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The young open cluster NGC 7067 using Strömgren photometry

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stw3302 ◽

2016 ◽

Vol 466 (3) ◽

pp. 3636-3647 ◽

Cited By ~ 2

Author(s):

M Monguió ◽

I Negueruela ◽

A Marco ◽

C González-Fernández ◽

J Alonso-Santiago ◽

...

Keyword(s):

Spectroscopic Data ◽

Milky Way ◽

Open Cluster ◽

Physical Parameters ◽

Wide Field ◽

Isaac Newton ◽

Cluster Distance ◽

Young Open Cluster ◽

Isaac Newton Telescope ◽

Spiral Arm

Abstract NGC 7067 is a young open cluster located in the direction between the first and the second Galactic quadrants and close to the Perseus spiral arm. This makes it useful for studies of the nature of the Milky Way spiral arms. Strömgren photometry taken with the Wide Field Camera at the Isaac Newton Telescope allowed us to compute individual physical parameters for the observed stars and hence to derive the cluster's physical parameters. Spectra from the 1.93-m telescope at the Observatoire de Haute-Provence helped to check and improve the results. We obtained photometry for 1233 stars, individual physical parameters for 515 and spectra for 9 of them. The 139 selected cluster members lead to a cluster distance of 4.4 ± 0.4 kpc, with an age below log10(t(yr)) = 7.3 and a present mass of 1260 ± 160 M⊙. The morphology of the data reveals that the centre of the cluster is at (α, δ) = (21: 24: 13.69, +48: 00: 39.2) J2000, with a radius of 6.1 arcmin. Strömgren and spectroscopic data allowed us to improve the previous parameters available for the cluster in the literature.

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A New Photometric Investigation of the Young Open Cluster NGC 663

Symposium - International Astronomical Union ◽

10.1017/s0074180900091919 ◽

1980 ◽

Vol 85 ◽

pp. 233-234

Author(s):

S. M. Hassan ◽

A. I. Othman

Keyword(s):

Spectral Type ◽

Galactic Plane ◽

Open Cluster ◽

Outer Edge ◽

Late Type ◽

Photographic Material ◽

Young Open Cluster ◽

Photometric Investigation ◽

Perseus Arm

The investigation of the open cluster NGC 663, based on the application of the method of UBV three colour photometry and the use of new photographic material, lead to a new distance to the cluster of 2550pc, E(B-V) & E(U-B) colour excesses of 0.74 & 0.53 mag and consequently a total visual absorption AV of 2.22 mag. An age of 3.9 × 107 y and a spectral type B2-B3 can be estimated for it; accordingly, it fits well the Perseus Arm (+1) near the outer edge and lies below the galactic plane at a distance of 47 pc.From the distribution of 476 stars investigated, around both the ZAMS and the apparent centre of the cluster, 270 probable physical member stars could be separated from the field stars and neither late type giants nor a giant branch are in existence.

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