J/AZh/89/674 Dynamical parameters of open clusters (Danilov+, 2012)
Non-stationarity parameters of open clusters.
Danilov V.M., Putkov S.I.
<Astron. Zh. 89, 674 (2012)>
=2012AZh....89..674D 2012AZh....89..674D
=2012ARep...56..609D 2012ARep...56..609D
ADC_Keywords: Clusters, open
Abstract:
Presented are the estimates of open cluster dynamical parameters: the
cluster core density contrast, the stellar velocity dispersions
allowing for influence of Galaxy external field and non-stationarity
of the cluster, the oscillation periods of the cluster and the cluster
core, the amplitudes of oscillations of a cluster virial factor and a
radius of the cluster core. All the values were analytically received
as a result solution of the gross dynamical equations for spherical
and ellipsoidal cluster models.
Description:
α0 - is the mean value of a virial factor, δα-is
the amplitude of virial factor oscillations, ν=ρc/ρ0-is
the density contrast (ρc - is the mean density of a cluster
core, ρ0 - is the cluster centre density), NK/N - is the ratio
of the stars number in a cluster received by King's distribution and
by stellar counts, P1-is the period of cluster core oscillations,
P2 - is the period of cluster oscillations, δR1/R10-is the
relative amplitude of core radius oscillations,
λ=σ/σiz, σiz2 - is the velocity
dispersion of an isolated virialized cluster, σ2,
σ12, σ22 - are the velocity dispersions of
nonisolated nonsteady clusters with spherical halo; with ellipsoidal
halo elongated to the centre of Galaxy; with ellipsoidal halo
elongated to the direction of cluster motion correspondingly. Errors
of values α0, δα, δR1/R10, P1 have
been estimated by the assumption of the normal distribution of the
values M (the mass of a cluster), R2 (the radius of a cluster), ξ
(the ratio of core radius to halo radius), µ (the ratio of core
mass to halo mass). Assuming a deviation of one of the four values
equal to zero we receive four sections of 1σ-errors ellipsoid.
These sections are the spheres of radius 20.5. Taking points on each
sphere with the step 0.25*π on angular coordinates we receive 96
points on a surface of the 1σ-errors ellipsoid. The values
α0, δα, δR1/R10, P1 were calculated in
the 96 points. The centre of the ellipsoidal was used for calculation
of the mean values. The errors of the values were computed as
root-mean-squire deviations of 96 values from the same mean values.
The errors of the others values of the catalog were computed by the
errors calculation rule of indirect measuring.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 55 87 List of non-stationarity parameters
table4.dat 64 87 List of non-stationarity parameters
table5.dat 48 87 List of non-stationarity parameters
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name
10- 15 F6.3 --- alpha0 ? α0, the mean value of a virial factor
17- 21 F5.3 --- e_alpha0 ? The error of α0
23- 28 F6.4 --- dalpha ? δα, the amplitude of virial
factor oscillations
30- 35 F6.4 --- e_dalpha ? The error of δα
37- 40 F4.1 --- nu ? ν, the density contrast
42- 45 F4.1 --- e_nu ? The error of ν
47- 50 F4.2 --- NK/N The ratio NK/N, number of stars from a
King's distribution relative to stellar counts
52- 55 F4.2 --- e_NK/N The error of NK/N
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name
10- 14 F5.2 Myr P1 The period of cluster core oscillations
16- 20 F5.2 Myr e_P1 The error of P1
22- 26 F5.2 Myr P2 ? The period of cluster oscillations
28- 32 F5.2 Myr e_P2 ? The error of P2
34- 38 F5.3 --- d(R1/R10) The relative amplitude of core radius
oscillation, δR1/R10
40- 44 F5.3 --- e_d(R1/R10) The error of δR1/R10
46- 49 F4.2 pc/Myr sigma σ, the root of a star velocity
dispersion in a case of the spherical halo
51- 54 F4.2 pc/Myr e_sigma The error of σ
56- 59 F4.2 --- lambda λ=σ/σiz, the ratio of
velocity dispersion to that of an
isolated virialized cluster σiz
61- 64 F4.2 --- e_lambda The error of λ
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name
10- 13 F4.2 pc/Myr sigma1 σ1, the root of a star velocity
dispersion in a case of the ellipsoidal halo
elongated to the centre of Galaxy
15- 18 F4.2 pc/Myr e_sigma1 The error of σ1
20- 23 F4.2 --- lambda1 λ1=σ1/σiz (relative
to isolated virialized cluster)
25- 28 F4.2 --- e_lambda1 The error of λ1
30- 33 F4.2 pc/Myr sigma2 σ2, the root of a star velocity
dispersion in a case of the ellipsoidal halo
elongated to the direction of cluster motion
35- 38 F4.2 pc/Myr e_sigma2 The error of σ2
40- 43 F4.2 --- lambda2 λ2=σ2/σiz (relative
to isolated virialized cluster)
45- 48 F4.2 --- e_lambda2 The error of λ2
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Acknowledgements:
Vladimir Michailovich Danilov, Vladimir.Danilov(at)usu.ru
Stanislav Igorevich Putkov, Putkov_S(at)mail.ru
(End) Patricia Vannier [CDS] 10-Dec-2012