J/A+A/554/A81 Abundances of 16 giants in M75 (Kacharov+, 2013)
A comprehensive chemical abundance study of the outer halo globular cluster M75.
Kacharov N., Koch A., McWilliam A.
<Astron. Astrophys. 554, A81 (2013)>
=2013A&A...554A..81K 2013A&A...554A..81K
ADC_Keywords: Clusters, globular ; Stars, giant ; Abundances
Keywords: stars: abundances - globular clusters: general -
globular clusters: individual: M 75 - Galaxy: halo
Abstract:
M75 is a relatively young Globular Cluster (GC) found at 15kpc from
the Galactic centre at the transition region between the inner and
outer Milky Way halos. Our aims are to perform a comprehensive
abundance study of a variety of chemical elements in this GC such as
to investigate its chemical enrichment history in terms of early star
formation, and to search for any multiple populations. We have
obtained high resolution spectroscopy with the MIKE instrument at the
Magellan telescope for 16 red giant stars. Their membership within the
GC is confirmed from radial velocity measurements. Our chemical
abundance analysis is performed via equivalent width measurements and
spectral synthesis, assuming local thermodynamic equilibrium (LTE). We
present the first comprehensive abundance study of M75 to date. The
cluster is metal-rich ([Fe/H]=-1.16±0.02dex,
[alpha/Fe]=+0.30±0.02dex), and shows a marginal spread in [Fe/H] of
0.07dex, typical of most GCs of similar luminosity. A moderately
extended O-Na anticorrelation is clearly visible, likely showing three
generations of stars, formed on a short timescale. Additionally the
two most Na-rich stars are also Ba-enhanced by 0.4 and 0.6dex,
respectively, indicative of pollution by lower mass (M∼4-5M☉)
Asymptotic Giant Branch (AGB) stars. The overall n-capture element
pattern is compatible with predominant r-process enrichment, which is
rarely the case in GCs of such a high metallicity.
Description:
Full Table 2 and Table 5 are only available online. Table 2 contains
the line-list and equivalent widths for all stars in our sample.
Table 5 contains the derived abundances of each element for each star
relative to hydrogen (logεH=12). The reduced spectra of the
16 giant stars in our sample are also available in ASCII format.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 58 16 Star list (from Kravtsov et al. 2007,
Cat. J/A+A/469/529)
table2.dat 89 224 Line-list and equivalent widths
table5.dat 479 16 Derived abundances relative to hydrogen
sp/* . 16 Individual spectra
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See also:
J/A+A/469/529 : UBVI photometry of NGC 6864 (Kravtsov+, 2007)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Star Star sequential number,
<Cl* NGC 6864 KAM NNN> in Simbad
6- 7 I2 h RAh Right ascension (J2000)
9- 10 I2 min RAm Right ascension (J2000)
12- 17 F6.3 s RAs Right ascension (J2000)
19 A1 --- DE- Declination sign (J2000)
20- 21 I2 deg DEd Declination (J2000)
23- 24 I2 arcmin DEm Declination (J2000)
26- 30 F5.2 arcsec DEs Declination (J2000)
32- 37 F6.3 mag Vmag V magnitude
39- 44 F6.3 mag Umag ? U magnitude
46- 51 F6.3 mag Bmag B magnitude
53- 58 F6.3 mag Imag I magnitude
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- El Element name and ionisation stage
6- 12 F7.2 0.1nm lambda Wavelength in angstroms
14- 17 F4.2 eV EP Excitation potential
19- 25 F7.3 [-] loggf Oscillator strength
27- 29 I3 0.1pm EW239 ?=- Equivalent widths for star #239
31- 33 I3 0.1pm EW251 ?=- Equivalent widths for star #251
35- 37 I3 0.1pm EW442 ?=- Equivalent widths for star #442
39- 41 I3 0.1pm EW461 ?=- Equivalent widths for star #461
43- 45 I3 0.1pm EW483 ?=- Equivalent widths for star #483
47- 49 I3 0.1pm EW486 ?=- Equivalent widths for star #486
51- 53 I3 0.1pm EW503 ?=- Equivalent widths for star #503
55- 57 I3 0.1pm EW512 ?=- Equivalent widths for star #512
59- 61 I3 0.1pm EW583 ?=- Equivalent widths for star #583
63- 65 I3 0.1pm EW612 ?=- Equivalent widths for star #612
67- 69 I3 0.1pm EW655 ?=- Equivalent widths for star #655
71- 73 I3 0.1pm EW876 ?=- Equivalent widths for star #876
75- 77 I3 0.1pm EW901 ?=- Equivalent widths for star #901
79- 81 I3 0.1pm EW1251 ?=- Equivalent widths for star #1251
83- 85 I3 0.1pm EW1312 ?=- Equivalent widths for star #1312
87- 89 I3 0.1pm EW1459 ?=- Equivalent widths for star #1459
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Star Star number
6- 10 F5.2 [Sun] [FeI/H] ?=- [FeI/H] (Z=26) abundance
12- 15 F4.2 [Sun] e_[FeI/H] ?=- Error on [FeI/H]
17- 18 I2 --- o_[FeI/H] ?=- Number of FeI lines used
20- 24 F5.2 [Sun] [FeII/H] ?=- [FeII/H] (Z=26) abundance
26- 29 F4.2 [Sun] e_[FeII/H] ?=- Error on [FeII/H]
31- 32 I2 --- o_[FeII/H] ?=- Number of FeII lines used
34- 38 F5.2 [Sun] [O/H] ?=- [O/H] (Z=8) abundance
40- 43 F4.2 [Sun] e_[O/H] ?=- Error on [O/H]
45- 46 I2 --- o_[O/H] ?=- Number of O lines used
48- 52 F5.2 [Sun] [Na/H] ?=- [Na/H] (Z=11) abundance
54- 57 F4.2 [Sun] e_[Na/H] ?=- Error on [Na/H]
59- 60 I2 --- o_[Na/H] ?=- Number of Na lines used
62- 66 F5.2 [Sun] [Mg/H] ?=- [Mg/H] (Z=12) abundance
68- 70 F3.1 [Sun] e_[Mg/H] ?=- Error on [Mg/H]
72- 73 I2 --- o_[Mg/H] ?=- Number of Mg lines used
75- 79 F5.2 [Sun] [Al/H] ?=- [Al/H] (Z=13) abundance
81- 84 F4.2 [Sun] e_[Al/H] ?=- Error on [Al/H]
86- 87 I2 --- o_[Al/H] ?=- Number of Al lines used
89- 93 F5.2 [Sun] [Si/H] ?=- [Si/H] (Z=14) abundance
95- 98 F4.2 [Sun] e_[Si/H] ?=- Error on [Si/H]
100-101 I2 --- o_[Si/H] ?=- Number of Si lines used
103-107 F5.2 [Sun] [K/H] ?=- [K/H] (Z=19) abundance
109-112 F4.2 [Sun] e_[K/H] ?=- Error on [K/H]
114-115 I2 --- o_[K/H] ?=- Number of K lines used
117-121 F5.2 [Sun] [Ca/H] ?=- [Ca/H] (Z=20) abundance
123-126 F4.2 [Sun] e_[Ca/H] ?=- Error on [Ca/H]
128-129 I2 --- o_[Ca/H] ?=- Number of Ca lines used
131-135 F5.2 [Sun] [Sc/H] ?=- [Sc/H] (Z=21) abundance
137-140 F4.2 [Sun] e_[Sc/H] ?=- Error on [Sc/H]
142-143 I2 --- o_[Sc/H] ?=- Number of Sc lines used
145-149 F5.2 [Sun] [TiI/H] ?=- [TiI/H] (Z=22) abundance
151-154 F4.2 [Sun] e_[TiI/H] ?=- Error on [TiI/H]
156-157 I2 --- o_[TiI/H] ?=- Number of TiI lines used
159-163 F5.2 [Sun] [TiII/H] ?=- [TiII/H] (Z=22) abundance
165-168 F4.2 [Sun] e_[TiII/H] ?=- Error on [TiII/H]
170-171 I2 --- o_[TiII/H] ?=- Number of TiII lines used
173-177 F5.2 [Sun] [V/H] ?=- [V/H] (Z=23) abundance
179-182 F4.2 [Sun] e_[V/H] ?=- Error on [V/H]
184-185 I2 --- o_[V/H] ?=- Number of V lines used
187-191 F5.2 [Sun] [Cr/H] ?=- [Cr/H] (Z=24) abundance
193-196 F4.2 [Sun] e_[Cr/H] ?=- Error on [Cr/H]
198-199 I2 --- o_[Cr/H] ?=- Number of Cr lines used
201-205 F5.2 [Sun] [Mn/H] ?=- [Mn/H] (Z=25) abundance
207-210 F4.2 [Sun] e_[Mn/H] ?=- Error on [Mn/H]
212-213 I2 --- o_[Mn/H] ?=- Number of Mn lines used
215-219 F5.2 [Sun] [Co/H] ?=- [Co/H] (Z=27) abundance
221-224 F4.2 [Sun] e_[Co/H] ?=- Error on [Co/H]
226-227 I2 --- o_[Co/H] ?=- Number of Co lines used
229-233 F5.2 [Sun] [Ni/H] ?=- [Ni/H] (Z=28) abundance
235-238 F4.2 [Sun] e_[Ni/H] ?=- Error on [Ni/H]
240-241 I2 --- o_[Ni/H] ?=- Number of Ni lines used
243-247 F5.2 [Sun] [Cu/H] ?=- [Cu/H] (Z=29) abundance
249-252 F4.2 [Sun] e_[Cu/H] ?=- Error on [Cu/H]
254-255 I2 --- o_[Cu/H] ?=- Number of Cu lines used
257-261 F5.2 [Sun] [Zn/H] ?=- [Zn/H] (Z=30) abundance
263-266 F4.2 [Sun] e_[Zn/H] ?=- Error on [Zn/H]
268-269 I2 --- o_[Zn/H] ?=- Number of Zn lines used
271-275 F5.2 [Sun] [Rb/H] ?=- [Rb/H] (Z=37) abundance
277-280 F4.2 [Sun] e_[Rb/H] ?=- Error on [Rb/H]
282-283 I2 --- o_[Rb/H] ?=- Number of Rb lines used
285-289 F5.2 [Sun] [Y/H] ?=- [Y/H] (Z=39) abundance
291-294 F4.2 [Sun] e_[Y/H] ?=- Error on [Y/H]
296-297 I2 --- o_[Y/H] ?=- Number of Y lines used
299-303 F5.2 [Sun] [Zr/H] ?=- [Zr/H] (Z=40) abundance
305-308 F4.2 [Sun] e_[Zr/H] ?=- Error on [Zr/H]
310-311 I2 --- o_[Zr/H] ?=- Number of Zr lines used
313-317 F5.2 [Sun] [Ba/H] ?=- [Ba/H] (Z=56) abundance
319-322 F4.2 [Sun] e_[Ba/H] ?=- Error on [Ba/H]
324-325 I2 --- o_[Ba/H] ?=- Number of Ba lines used
327-331 F5.2 [Sun] [La/H] ?=- [La/H] (Z=57) abundance
333-336 F4.2 [Sun] e_[La/H] ?=- Error on [La/H]
338-339 I2 --- o_[La/H] ?=- Number of La lines used
341-345 F5.2 [Sun] [Ce/H] ?=- [Ce/H] (Z=58) abundance
347-350 F4.2 [Sun] e_[Ce/H] ?=- Error on [Ce/H]
352-353 I2 --- o_[Ce/H] ?=- Number of Ce lines used
355-359 F5.2 [Sun] [Pr/H] ?=- [Pr/H] (Z=59) abundance
361-364 F4.2 [Sun] e_[Pr/H] ?=- Error on [Pr/H]
366-367 I2 --- o_[Pr/H] ?=- Number of Pr lines used
369-373 F5.2 [Sun] [Nd/H] ?=- [Nd/H] (Z=60) abundance
375-378 F4.2 [Sun] e_[Nd/H] ?=- Error on [Nd/H]
380-381 I2 --- o_[Nd/H] ?=- Number of Nd lines used
383-387 F5.2 [Sun] [Sm/H] ?=- [Sm/H] (Z=62) abundance
389-392 F4.2 [Sun] e_[Sm/H] ?=- Error on [Sm/H]
394-395 I2 --- o_[Sm/H] ?=- Number of Sm lines used
397-401 F5.2 [Sun] [Eu/H] ?=- [Eu/H] (Z=63) abundance
403-406 F4.2 [Sun] e_[Eu/H] ?=- Error on [Eu/H]
408-409 I2 --- o_[Eu/H] ?=- Number of Eu lines used
411-415 F5.2 [Sun] [Gd/H] ?=- [Gd/H] (Z=64) abundance
417-420 F4.2 [Sun] e_[Gd/H] ?=- Error on [Gd/H]
422-423 I2 --- o_[Gd/H] ?=- Number of Gd lines used
425-429 F5.2 [Sun] [Dy/H] ?=- [Dy/H] (Z=66) abundance
431-434 F4.2 [Sun] e_[Dy/H] ?=- Error on [Dy/H]
436-437 I2 --- o_[Dy/H] ?=- Number of Dy lines used
439-443 F5.2 [Sun] [Er/H] ?=- [Er/H] (Z=68) abundance
445-448 F4.2 [Sun] e_[Er/H] ?=- Error on [Er/H]
450-451 I2 --- o_[Er/H] ?=- Number of Er lines used
453-457 F5.2 [Sun] [Hf/H] ?=- [Hf/H] (Z=72) abundance
459-462 F4.2 [Sun] e_[Hf/H] ?=- Error on [Hf/H]
464-465 I2 --- o_[Hf/H] ?=- Number of Hf lines used
467-471 F5.2 [Sun] [Th/H] ?=- [Th/H] (Z=90) abundance
473-476 F4.2 [Sun] e_[Th/H] ?=- Error on [Th/H]
478-479 I2 --- o_[Th/H] ?=- Number of Th lines used
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 16 F16.11 0.1nm lambda [4794/9172] Wavelength (Å)
20- 36 F17.11 --- Flux Flux
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Acknowledgements:
Nikolay Kacharov, n.kacharov(at)lsw.uni-heidelberg.de
(End) Nikolay Kacharov [LSW, Heidelberg], Patricia Vannier [CDS] 18-Apr-2013