J/AZh/93/49 Abundances in Galactic open clusters (Marsakov+, 2016)
Peculiarities of α-element abundances in Galactic open clusters.
Marsakov V.A., Gozha M.L., Koval' V.V., Shpigel' L.V.
<Astron. Zh. 93, 49 (2016)>
=2016AZh....93...49M 2016AZh....93...49M (SIMBAD/NED BibCode)
=2016ARep...60...43M 2016ARep...60...43M
ADC_Keywords: Milky Way ; Clusters, open ; Abundances
Abstract:
A catalog compiling the parameters of 346 open clusters, including
their metallicities, positions, ages, and velocities has been
composed. The elements of the Galactic orbits for 272 of the clusters
have been calculated. Spectroscopic determinations of the relative
abundances, [el/Fe], for 14 elements synthesized in various nuclear
processes averaged over data from 109 publications are presented for
90 clusters. The compiled data indicate that the relative abundances
of primary α elements (oxygen and magnesium) exhibit different
dependences on metallicity, age, Galactocentric distance, and the
elements of the Galactic orbits in clusters with high, elongated
orbits satisfying the criterion (Zmax2+4e2)1/2>0.40 and in
field stars of the Galactic thin disk (Zmax is the maximum distance of
the orbit from the Galactic plane in kiloparsec and e is the
eccentricity of the Galactic orbit). Since no systematic effects
distorting the relative abundances of the studied elements in these
clusters have been found, these difference suggest real differences
between clusters with high, elongated orbits and field stars. In
particular, this supports the earlier conclusion, based on an analysis
of the elements of the Galactic orbits, that some clusters formed as a
result of interactions between high-velocity,metal-poor clouds and the
interstellar medium of the Galactic thin disk. On average, clusters with
high, elongated orbits and metallicities [Fe/H]←0.1 display lower
relative abundances of the primary α elements than do field
stars. The low [O, Mg/Fe] ratios of these clusters can be understood
if the high-velocity clouds that gave rise to them were formed of
interstellar material from regions where the star-formation rate
and/or the masses of Type II supernovae were lower than near the
Galactic plane. It is also shown that, on average, the relative
abundances of the primary α elements are higher in relatively
metal-rich clusters with high, elongated orbits than in field stars.
This can be understood if clusters with [Fe/H]>-0.1 formed as a
result of interactions between metal-rich clouds with intermediate
velocities and the interstellar medium of the Galactic disk; such
clouds could form from returning gas in a so-called "Galactic
fountain".
Description:
Spectroscopic determinations of the relative abundances of
alpha-elements (O, Mg, Si, Ca, and Ti), slow neutron capture elements
(Y, Ba, La, Ce, Nd, and Zr), rapid neutron capture element (Eu), and
elements with an odd number of protons (Na, Al) are collected for 90
open clusters of the Galaxy. Metallicities are presented for 346
clusters. In addition catalog contains positions, ages, velocities,
elements of Galactic orbits for open clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 272 346 The catalogue data for 346 open clusters
refs.dat 85 115 References for [Fe/H] and [el/Fe]
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 20-2015)
J/PAZh/38/571 : Astrophysical parameters for 593 open clusters (Gozha+, 2012)
J/A+A/561/A93 : On the metallicity of open clusters. II. (Heiter+, 2014)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Cluster Cluster name
15- 22 F8.4 deg GLON Galactic longitude
24- 31 F8.4 deg GLAT Galactic latitude
33- 37 I5 pc d Heliocentric distance
39- 44 I6 pc x Heliocentric distance towards Gal. center
46- 50 I5 pc y Heliocentric distance towards Gal. rotation
52- 56 I5 pc z Heliocentric distance towards N. Gal. Pole
58- 62 F5.2 kpc RG Galactocentric distance
64- 68 F5.1 km/s VR ? Galactocentric cylindrical velocity
component towards Gal. anticenter
70- 74 F5.1 km/s VH ? Galactocentric cylindrical velocity
component towards Gal. rotation
76- 81 F6.1 km/s VZ ? Galactocentric cylindrical velocity
component towards N. Gal. Pole
83- 87 F5.3 --- e ? Orbital eccentricity
89- 94 F6.3 kpc Zmax ? Maximum distance above the Galactic plane
96-100 F5.2 kpc Ra ? Apogalactic distance
102-106 F5.2 kpc Rp ? Perigalactic distance
108-112 F5.3 Gyr Age ? Cluster age
114-119 F6.3 [Sun] [Fe/H] Cluster metallicity
121-126 A6 --- r_[Fe/H] References for [Fe/H], in refs.dat file
128-132 F5.2 [Sun] [O/Fe] ? Abundance [O/Fe]
134-138 F5.2 [Sun] [Na/Fe] ? Abundance [Na/Fe]
140-144 F5.2 [Sun] [Mg/Fe] ? Abundance [Mg/Fe]
146-150 F5.2 [Sun] [Al/Fe] ? Abundance [Al/Fe]
152-156 F5.2 [Sun] [Si/Fe] ? Abundance [Si/Fe]
158-162 F5.2 [Sun] [Ca/Fe] ? Abundance [Ca/Fe]
164-168 F5.2 [Sun] [Ti/Fe] ? Abundance [Ti/Fe]
170-174 F5.2 [Sun] [Y/Fe] ? Abundance [Y/Fe]
176-180 F5.2 [Sun] [Zr/Fe] ? Abundance [Zr/Fe]
182-186 F5.2 [Sun] [Ba/Fe] ? Abundance [Ba/Fe]
188-192 F5.2 [Sun] [La/Fe] ? Abundance [La/Fe]
194-198 F5.2 [Sun] [Ce/Fe] ? Abundance [Ce/Fe]
200-204 F5.2 [Sun] [Nd/Fe] ? Abundance [Nd/Fe]
206-210 F5.2 [Sun] [Eu/Fe] ? Abundance [Eu/Fe]
212-272 A61 --- r_[el/Fe] ? References for [el/Fe], in refs.dat file
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Ref [1/115] Reference code
5- 23 A19 --- BibCode BibCode
25- 48 A24 --- Aut Author's name
50- 85 A36 --- Com Comments
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Acknowledgements:
Marina Gozha, gozha_marina(at)mail.ru
(End) Patricia Vannier [CDS] 15-Jul-2016