J/AJ/144/95 Abundance in stars of the outer galactic disk. IV. (Yong+, 2012)
Elemental abundance ratios in stars of the outer galactic disk.
IV. A new sample of open clusters.
Yong D., Carney B.W., Friel E.D.
<Astron. J., 144, 95 (2012)>
=2012AJ....144...95Y 2012AJ....144...95Y
ADC_Keywords: Clusters, open ; Abundances ; Equivalent widths ; Extinction ;
Effective temperatures ; Photometry, infrared ; Photometry, UBV ;
Reddening
Keywords: Galaxy: abundances - Galaxy: disk -
open clusters and associations: general
Abstract:
We present radial velocities and chemical abundances for nine stars in
the old, distant open clusters Be18, Be21, Be22, Be32, and PWM4. For
Be18 and PWM4, these are the first chemical abundance measurements.
Combining our data with literature results produces a compilation of
some 68 chemical abundance measurements in 49 unique clusters. For
this combined sample, we study the chemical abundances of open
clusters as a function of distance, age, and metallicity. We confirm
that the metallicity gradient in the outer disk is flatter than the
gradient in the vicinity of the solar neighborhood. We also confirm
that the open clusters in the outer disk are metal-poor with
enhancements in the ratios [α/Fe] and perhaps [Eu/Fe]. All
elements show negligible or small trends between [X/Fe] and distance
(<0.02dex/kpc), but for some elements, there is a hint that the local
(RGC<13kpc) and distant (RGC>13kpc) samples may have different
trends with distance. There is no evidence for significant abundance
trends versus age (<0.04dex/Gyr). We measure the linear relation
between [X/Fe] and metallicity, [Fe/H], and find that the scatter
about the mean trend is comparable to the measurement uncertainties.
Comparison with solar neighborhood field giants shows that the open
clusters share similar abundance ratios [X/Fe] at a given metallicity.
While the flattening of the metallicity gradient and enhanced
[α/Fe] ratios in the outer disk suggest a chemical enrichment
history different from that of the solar neighborhood, we echo the
sentiments expressed by Friel et al. that definitive conclusions await
homogeneous analyses of larger samples of stars in larger numbers of
clusters. Arguably, our understanding of the evolution of the outer
disk from open clusters is currently limited by systematic abundance
differences between various studies.
Description:
We searched the WEBDA database (http://www.univie.ac.at/webda/) and
the recent literature to identify the following old (>2Gyr), distant
(RGC>10kpc) open clusters: Be18, Be21, Be22, Be32, and PWM4.
Individual stars were selected from optical and infrared
color-magnitude diagrams.
For our observations, we used the High Resolution Echelle Spectrometer
spectrograph on the Keck I Telescope on 2006 November 12 and 2006
December 27. On both occasions we used the red cross-disperser and the
B5 decker, which has a slit width of 0.86" and a slit length of 3.5".
On the November run, we binned the CCD 3*1 (spatial*spectral) and on
the December run we binned the CCD 2*1. We measured a spectral
resolution of R=47000 (σ=3000), and this value is close to the
expected value of R=48000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 63 14 Photometric data
table4.dat 67 5 Red clump data
table5.dat 52 9 Atmospheric parameters
table6.dat 78 228 Equivalent widths for program stars
abund.dat 33 153 Chemical abundances for the program stars
(tables 7-11)
table13.dat 148 68 Compilation of (LTE) abundance ratios for open
clusters
table14.dat 93 15 Mean [X/Fe] ratios, standard error of the mean, and
level of significance when comparing the inner and
outer disks for different boundary values
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/A+A/535/A30 : Abundance of 12 stars in open clusters (Carrera+, 2011)
J/AJ/142/59 : Chemical abundance in 10 open clusters (Jacobson+, 2011)
J/AJ/141/58 : NGC 2204 and NGC 2243 red giant abundances (Jacobson+, 2011)
J/ApJ/735/L46 : Spectroscopy of 64 K red giants (Bensby+, 2011)
J/AJ/139/1942 : EWs of red giants in 6 open clusters (Friel+, 2010)
J/A+A/511/A56 : Abundances of five open clusters (Pancino+, 2010)
J/AJ/137/4753 : Red giants EWs in 4 open clusters (Jacobson+, 2009)
J/A+A/480/79 : Abundances of giants in 5 Galactic clusters
(Bragaglia+, 2008)
J/A+A/488/943 : Abundances of giants in 4 Galactic clusters (Sestito+, 2008)
J/A+A/476/217 : Fundamental parameters of 5 old open clusters
(Carraro+, 2007)
J/A+A/465/185 : Element abundances of 7 stars of NGC 6253 (Sestito+, 2007)
J/MNRAS/368/471 : Berkeley 32 BVI photometry and spectroscopy (D'Orazi+, 2006)
J/AJ/130/1111 : Abundances of field red giants (Carney+, 2005, Paper II)
J/AJ/129/2725 : Equivalent widths of red giants in Berkeley 17 (Friel+, 2005)
J/A+A/431/933 : Abundances of NGC 7789 evolved stars (Tautvaisiene+, 2005)
J/AJ/130/652 : EWs of 4 giants in Be22 and Be66 (Villanova+, 2005)
J/AJ/129/656 : Infrared photometry of NGC 6791 (Carney+, 2005)
J/A+A/423/199 : Chemical abundances of planetary nebulae (Costa+, 2004)
J/A+A/392/491 : Galactic abundance gradient. III. (Andrievsky+, 2002)
J/MNRAS/299/834 : Berkeley 21 BVI photometry (Tosi+, 1998)
J/A+AS/121/455 : BVI photometry of stars in Berkeley 18 (Kaluzny 1997)
J/A+AS/108/151 : Open clusters CCD photometry. I. (Kaluzny, 1994)
J/AcA/41/167 : UBV photometry in Berkeley 32 (Kaluzny+, 1991)
http://www.univie.ac.at/webda/ : WEBDA database
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Star Star name
11- 12 I2 h RAh 2MASS Hour of Right Ascension (J2000)
14- 15 I2 min RAm 2MASS Minute of Right Ascension (J2000)
17- 20 F4.1 s RAs 2MASS Second of Right Ascension (J2000)
22 A1 --- DE- 2MASS Sign of the Declination
23- 24 I2 deg DEd 2MASS Degree of Declination (J2000)
26- 27 I2 arcmin DEm 2MASS Arcminute of Declination (J2000)
29- 32 F4.1 arcsec DEs 2MASS Arcsecond of Declination (J2000)
34- 38 F5.2 mag Vmag ? The V band magnitude
40- 43 F4.2 mag B-V ? The B-V color index
45- 48 F4.2 mag V-Ic ? The (V-IC) color index
50- 55 F6.3 mag Kmag 2MASS K band magnitude
57- 61 F5.3 mag J-K 2MASS (J-K) color index
63 I1 --- Ref ? Reference (1)
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Note (1): Reference as follows:
1 = Kaluzny (1997, cat. J/A+AS/121/455);
2 = Tosi et al. (1998, cat. J/MNRAS/299/834);
3 = Kaluzny (1994, cat. J/A+AS/108/151);
4 = Kaluzny & Mazur (1991, cat. J/AcA/41/167);
5 = Ortolani et al. (2005A&A...437..531O 2005A&A...437..531O).
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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- 11 A11 --- Cluster Cluster name
13- 17 F5.2 mag <Kmag> Mean K magnitude
19- 22 F4.2 mag <J-K> Mean (J-K) color index
24- 27 F4.1 [Sun] [Fe/H] Metallicity from our spectroscopic measurement
29- 32 F4.2 mag (J-K)0 (J-K)0
34- 37 F4.2 mag E(J-K) Reddening E(J-K) [=0.52E(B-V)]. See
section 2.4 for more details
39- 42 F4.2 mag E(B-V) Estimated reddening
44- 48 F5.2 mag (m-M)0 Distance modulus (m-M)0
50- 52 F3.1 kpc Dist Estimated distance
54- 58 F5.2 kpc Rgc Galactocentric distance RGC
60- 63 F4.2 mag Red Reddening from the WEBDA database (1)
65- 67 F3.1 kpc d Distance from the WEBDA database (1)
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Note (1): WEBDA database at http://www.univie.ac.at/webda/.
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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- 9 A9 --- Star Star name
11- 14 I4 K Teff1 Photometric effective temperature (1)
16- 18 F3.1 [cm/s2] logg1 Photometric surface gravity (1)
20- 23 I4 K Teff2 Photometric effective temperature (2)
25- 27 F3.1 [cm/s2] logg2 Photometric surface gravity (2)
29- 32 I4 K Teff3 Spectroscopic effective temperature (3)
34- 36 F3.1 [cm/s2] logg3 Spectroscopic surface gravity (3)
38- 41 F4.1 [Sun] [m/H] Spectroscopic metallicity of the model (3)
43- 46 F4.2 km/s xi Spectroscopic microturbulent
velocity (ξt) (3)
48- 52 F5.2 [Sun] [Fe/H] Spectroscopic derived metallicity (3)
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Note (1): Estimates obtained using (1) the photometric data in Table 2, (2) the
distance, reddening, and metallicity from Table 4, and (3) the
Ramirez & Melendez (2005ApJ...626..465R 2005ApJ...626..465R) IRFM calibration.
Note (2): Estimates obtained using (1) the photometric data in Table 2, (2) the
distance, reddening, and metallicity from Table 4, and (3) the
Alonso et al. (1999A&AS..140..261A 1999A&AS..140..261A) IRFM calibration.
Note (3): Quantities are derived using the spectroscopic methods described
in Section 3.1 of this paper.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 7 F7.2 0.1nm lambda [4439.88/8075.15] Wavelength; in Å
9- 12 F4.1 --- Ion Atomic element and ionization number
14- 17 F4.2 eV LEP Lower excitation potential
19- 24 F6.2 [-] loggf Log of the oscillator strength
26- 30 F5.1 10-13m E1163 ? Be18-1163 equivalent width; in mÅ
32- 36 F5.1 10-13m E1383 ? Be18-1383 equivalent width; in mÅ
38- 42 F5.1 10-13m ET50 ? Be21-T50 equivalent width; in mÅ
44- 48 F5.1 10-13m ET51 ? Be21-T51 equivalent width; in mÅ
50- 54 F5.1 10-13m E414 ? Be22-414 equivalent width; in mÅ
56- 60 F5.1 10-13m E643 ? Be22-643 equivalent width; in mÅ
62- 66 F5.1 10-13m E16 ? Be32-16 equivalent width; in mÅ
68- 72 F5.1 10-13m E18 ? Be32-18 equivalent width; in mÅ
74- 78 F5.1 10-13m ERGB1 ? PWM-RGB1 equivalent width; in mÅ
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Byte-by-byte Description of file: abund.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Star Star name
11- 19 A9 --- Ion Species
21- 25 F5.2 [Sun] [X/Fe] ? Chemical abundance ratio
27- 30 F4.2 [Sun] e_[X/Fe] ? sigma uncertainty in [X/Fe]
32- 33 I2 --- N ? Number of lines
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Byte-by-byte Description of file: table13.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Cluster Cluster name
12- 32 A21 --- r_Age Source reference (1)
34- 38 F5.2 Gyr Age ? Age from the individual papers
39 A1 --- f_Age Flag on Age (c = age from Bragaglia & Tosi,
2006AJ....131.1544B 2006AJ....131.1544B)
41- 45 F5.2 kpc Dist ? Galactocentric distance from the individual
papers
46 A1 --- f_Dist Flag on Dist (c = distance from Bragaglia &
Tosi, 2006AJ....131.1544B 2006AJ....131.1544B)
48- 52 F5.2 Gyr Age2 ? Age from Salaris et al. (2004A&A...414..163S 2004A&A...414..163S)
54- 58 F5.2 kpc Dist2 ? Galactocentric distance (from Salaris et al.,
2004A&A...414..163S 2004A&A...414..163S)
60- 64 F5.2 [-] [Fe/H] The [Fe/H] number abundance
66- 70 F5.2 [-] [O/Fe] ? The [O/Fe] number abundance
72- 76 F5.2 [-] [Na/Fe] ? The [Na/Fe] number abundance
78- 82 F5.2 [-] [Mg/Fe] ? The [Mg/Fe] number abundance
84- 88 F5.2 [-] [Al/Fe] ? The [Al/Fe] number abundance
90- 94 F5.2 [-] [Si/Fe] ? The [Si/Fe] number abundance
96-100 F5.2 [-] [Ca/Fe] ? The [Ca/Fe] number abundance
102-106 F5.2 [-] [Ti/Fe] ? The [Ti/Fe] number abundance
108-112 F5.2 [-] [Mn/Fe] ? The [Mn/Fe] number abundance
114-118 F5.2 [-] [Co/Fe] ? The [Co/Fe] number abundance
120-124 F5.2 [-] [Ni/Fe] ? The [Ni/Fe] number abundance
126-130 F5.2 [-] [Zr/Fe] ? The [Zr/Fe] number abundance
132-136 F5.2 [-] [Ba/Fe] ? The [Ba/Fe] number abundance
138-142 F5.2 [-] [La/Fe] ? The [La/Fe] number abundance
144-148 F5.2 [-] [Eu/Fe] ? The [Eu/Fe] number abundance
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Note (1): Reference as follows:
Bragaglia01 = Bragaglia et al. (2001, cat. J/AJ/121/327);
Bragaglia08 = Bragaglia et al. (2008, cat. J/A+A/480/79);
Carraro04 = Carraro et al. (2004AJ....128.1676C 2004AJ....128.1676C);
Carraro07 = Carraro et al. (2007, J/A+A/476/217);
Carrera11 = Carrera & Pancino (2011, cat. J/A+A/535/A30);
Carretta04 = Carretta et al. (2004A&A...422..951C 2004A&A...422..951C);
Carretta05 = Carretta et al. (2005A&A...441..131C 2005A&A...441..131C);
Carretta07 = Carretta et al. (2007A&A...473..129C 2007A&A...473..129C);
de Silva06 = De Silva et al. (2006AJ....131..455D 2006AJ....131..455D);
de Silva07 = De Silva et al. (2007AJ....133.1161D 2007AJ....133.1161D);
Friel10 = Friel et al. (2005, cat. J/AJ/129/2725),
Jacobson et al. (2008AJ....135.2341J 2008AJ....135.2341J),
Jacobson et al. (2009, cat. J/AJ/137/4753),
Friel et al. (2010, cat. J/AJ/139/1942);
Hill99 = Hill & Pasquini (1999A&A...348L..21H 1999A&A...348L..21H) ;
Jacobson11a = Jacobson et al. (2011, cat. J/AJ/141/58);
Jacobson11b = Jacobson et al. (2011, cat. J/AJ/142/59);
Pancino10 = Pancino et al. (2010, cat. J/A+A/511/A56);
Paulson03 = Paulson et al. (2003AJ....125.3185P 2003AJ....125.3185P);
Sestito08 = Sestito et al. (2006A&A...458..121S 2006A&A...458..121S),
Sestito et al. (2007, cat. J/A+A/465/185),
Sestito et al. (2008, cat. J/A+A/488/943),
Bragaglia et al. (2008, cat. J/A+A/480/79);
Tautvaisiene05 = Tautvaisiene et al. (2005, cat. J/A+A/431/933);
Villanova05 = Villanova et al. (2005, cat. J/AJ/130/652);
Y05 = Yong et al. (2005AJ....130..597Y 2005AJ....130..597Y).
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Byte-by-byte Description of file: table14.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Ion Species
14- 18 F5.2 [-] Ab10i Mean [X/Fe] ratio in the inner disk for a
boundary value of RGC=10kpc
20- 23 F4.2 [-] e_Ab10i Standard error in Ab10i
25- 29 F5.2 [-] Ab10o Mean [X/Fe] ratio in the outer disk for a
boundary value of RGC=10kpc
31- 34 F4.2 [-] e_Ab10o Standard error in Ab10o
36- 39 F4.2 [-] Sig10 Level of significance (see Section 4.1 for
more details) for a boundary value of
RGC=10kpc
41- 45 F5.2 [-] Ab13i Mean [X/Fe] ratio in the inner disk for a
boundary value of RGC=13kpc
47- 50 F4.2 [-] e_Ab13i Standard error in Ab13i
52- 56 F5.2 [-] Ab13o Mean [X/Fe] ratio in the outer disk for a
boundary value of RGC=13kpc
58- 61 F4.2 [-] e_Ab13o Standard error in Ab13o
63- 66 F4.2 [-] Sig13 Level of significance (see Section 4.1 for
more details) for a boundary value of
RGC=13kpc
68- 72 F5.2 [-] Ab15i Mean [X/Fe] ratio in the inner disk for a
boundary value of RGC=15kpc
74- 77 F4.2 [-] e_Ab15i Standard error in Ab15i
79- 83 F5.2 [-] Ab15o Mean [X/Fe] ratio in the outer disk for a
boundary value of RGC=15kpc
85- 88 F4.2 [-] e_Ab15o Standard error in Ab15o
90- 93 F4.2 [-] Sig15 Level of significance (see Section 4.1 for
more details) for a boundary value of
RGC=15kpc
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History:
From electronic version of the journal
References:
Yong et al. Paper I 2005AJ....130..597Y 2005AJ....130..597Y
Carney et al. Paper II 2005AJ....130.1111C 2005AJ....130.1111C Cat. J/AJ/130/1111
Yong et al. Paper III 2006AJ....131.2256Y 2006AJ....131.2256Y
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 18-Oct-2013