Chemical Abundances of the Highly Obscured Galactic Globular Clusters 2MASS GC02 and Mercer 5

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(1)PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 127:329–339, 2015 April © 2015. The Astronomical Society of the Pacific. All rights reserved. Printed in U.S.A.. Chemical Abundances of the Highly Obscured Galactic Globular Clusters 2MASS GC02 and Mercer 5 FRANCISCO PEÑALOZA,1 PETER PESSEV,2 SERGIO VAŚQUEZ,3 JURA BORISSOVA,4 RADOSTIN KURTEV,4 MANUELA ZOCCALI3. AND. Received 2014 June 17; accepted 2015 January 21; published 2015 March 19. ABSTRACT. We present the first high spectral resolution abundance analysis of two newly discovered Galactic globular clusters, namely, Mercer 5 and 2MASS GC02, residing in regions of high interstellar reddening in the direction of the Galactic center. The data were acquired with the Phoenix high-resolution near-infrared echelle spectrograph at Gemini South (R ∼ 50; 000) in the 15,500.0–15,575.0 spectral region. Iron, oxygen, silicon, titanium, and nickel abundances were derived for two red giant stars, in each cluster, by comparing the entire observed spectrum with a grid of synthetic spectra generated with MOOG. We found [Fe/H] values of 0:86 0:12 and 1:08 0:13 for Mercer 5 and 2MASS GC02, respectively. The [O/Fe], [Si/Fe], and [Ti/Fe] ratios of the measured stars of Mercer 5 follow the general trend of both bulge field and cluster stars at this metallicity, and are enhanced by ≥ þ 0:3. The 2MASS GC02 stars have relatively lower ratios, but still compatible with other bulge clusters. Based on metallicity and abundance patterns of both objects, we conclude that these are typical bulge globular clusters. Online material: color figures. key data for studies of the origin and evolution of stellar populations, since they carry characteristic signatures of the objects that enrich the interstellar gas. The Galactic bulge globular clusters are relatively poorly understood stellar systems. The number of bulge globular cluster stars for which detailed chemical abundance information is available and is considerably smaller compared to stars in halo clusters. Moreover, the advent of the new generation extensive surveys such as SDSS (Abazajian et al. 2009), 2MASS (Skrutskie et al. 2006), GLIMPSE (Benjamin et al. 2003), and VISTA Variables in the Via Lactea (VVV) Public Survey (Minniti et al. 2010; Saito et al. 2012) yielded detection of several new Galactic globular clusters (GGCs). The December 2010 compilation of the Harris (1996) catalog included seven new GGCs not present in the February 2003 version, but several more cluster candidates have been proposed in the last years: SDSSJ1257+3419 (Sakamoto & Hasegawa 2006), FSR 584 (Bica et al. 2007), FSR 1767 (Bonatto et al. 2007), FSR 190 (Froebrich et al. 2008), Pfleiderer 2 (Ortolani et al. 2009), VVV CL001 (Minniti et al. 2011), Mercer 5 (Longmore et al. 2011), VVV CL002 (Moni Bidin et al. 2011), and Kronberger 49 (Ortolani et al. 2012). Thus, detailed investigation of these newly discovered members of the globular cluster family can contribute significantly to the global understanding of the whole system. In this study, we report the results of our high-resolution Phoenix spectroscopy of selected red giant stars of two newly discovered globular clusters, 2MASS GC02 and Mercer 5, projected in the bulge area of the Galaxy. The globular cluster 2MASS GC02 was reported by Hurt et al. (2000) and was detected within the Two Micron All Sky Survey (2MASS).. 1. INTRODUCTION The properties of globular clusters and their stellar populations provide fundamental information on the environment where galaxies formed and on the Galactic formation process, and are also a basic ingredient for the understanding of the stellar populations in external galaxies. Moreover, the properties of globular clusters are deeply connected with the history of their host galaxy. We believe today that galaxy collisions, galaxy cannibalism, and galaxy mergers leave their imprint on the globular cluster population of any given galaxy. Thus, when investigating globular clusters, we hope to be able to use them as an acid test for our understanding of the formation and evolution of galaxies. The Galactic bulge is particularly important in the context of galaxy formation, as it is the only bulge that can be resolved into stars down to the bottom of the main sequence, and for which chemical abundances can be obtained with high-resolution spectra. Determinations of detailed chemical compositions are 1. Insituto de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaiso Av. Gran Bretana 1111, Valparaiso, Chile; [email protected]. 2 Instituto de Astrofísica de Canarias (IAC) E-38205 La Laguna, Tenerife, Spain; [email protected]. Also at: Gemini Observatory South, La Serena, Chile. 3 Instituto de Astrofísica, Pontifica Universidad Católica de Chile; Milenium Institute of Astrophysics, MAS Av. Vicuña Mackenna 4860, Santiago, Chile; [email protected], [email protected]. 4 Insituto de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaiso. Also at: Milenium Institute of Astrophysics, MAS Av. Gran Bretana 1111, Valparaiso, Chile; [email protected], [email protected].. 329.

(2) 330. PEÑALOZA ET AL. TABLE 1 INFORMATION ABOUT. THE. TARGETED CLUSTERS. ID (1). R.A. (2). Decl. (3). l (deg) (4). b (deg) (5). D (arcmin) (6). EðJ KÞ (mag) (7). ðm MÞ0 (mag) (8). Refs. (9). 2M GC02 Mercer 5. 18 09 37 18 23 19. −20 46 44 −13 40 02. 9.78 17.59. −0.62 −0.11. 1.9 ± 0.2 0.60. 3.0 ± 0.1 2.1 ± 0.7. 13.54 ± 0.15 14.29a. Borissova et al. (2007); Hurt et al. (2000) Mercer et al. (2005); Longmore et al. (2011). NOTES.—Column (1) is the cluster ID, followed by the equatorial coordinates of the object [columns (2) and (3)]. Units of right ascension are hours, minutes, and seconds. Units of declination are degrees, minutes, and seconds. The Galactic coordinates are presented in columns (4) and (5). Column (6) shows the apparent diameter of the cluster, followed by an estimate of the color excess EðJ KÞ in column (7). The distance modulus to the object is listed in column (8), followed by the list of the references to the various sources of information used in the table. a The maximum value from Longmore et al. (2011) is considered.. Later, Borissova et al. (2007) obtained deep-infrared images and low-resolution K-band spectra. Based on the analysis of the J Ks versus Ks color–magnitude diagram and spectroscopically derived metallicities and radial velocities of 15 stars, they concluded that the cluster is moderately metal-rich (½Fe=H ¼ 1:1) and has a relatively high radial velocity. Its horizontal branch appears to be predominantly red, though the photometry cannot rule out presence of a blue component, as seen in NGC 6388 and NGC 6441. Comparison with the existing kinematic and abundance information for the GGCs indicates that 2MASS GC02 most probably belongs to the bulge subpopulation, although inner halo association cannot be ruled out. Recently, Alonso-García et al. (2015) discovered 29 new variables inside the tidal radius of 2MASS GC02, using the Vista varaibles in the Via Lactea (VVV) ESO Large Public Survey. Eight of these variables are classified as RR Lyrae stars. Using these newly discovered RR Lyrae stars, they found that the extinction toward the cluster is highly differential, and seems to follow a nonstandard law, thus putting the cluster closer to the galactic center (calculated distance of RGc ¼ 2:2 kpc). The dust-obscured Galactic star cluster Mercer 5 was investigated by Longmore et al. (2011). The analysis of the nearinfrared photometry from the United Kingdom Infrared Digital Sky Survey (UKIDSS) and the SofI/NTT near-IR spectroscopy indicate that the object almost certainly is a Galactic globular cluster, located at the edge of the Galactic bulge. The cluster suffers strong and variable extinction, located at a distance of approximately 5.5 kpc and is also moderately metalrich (½Fe=H ¼ 1:0). 2. DATA REDUCTION AND ANALYSIS Relevant information about our target clusters is presented in Table 1. Note that Mercer 5 is a newly discovered cluster (Mercer et al. 2005) and is still not included in the online version of the Harris (1996) catalog (2010 edition). Both globular clusters targeted for observations are located at low Galactic latitude, close to the plane of the Milky Way, in regions of high interstellar reddening (see Fig. 1). Hence, the Phoenix highresolution near-infrared echelle spectrograph (Hinkle et al. 1998) mounted at Gemini South 8 m telescope was a natural choice for the observations. The combination of large telescope aperture. and high spectral resolution is crucial for accurate abundance determination, considering the apparent magnitudes of the individual red giants in our sample. More specifically, the data reported in Table 1 are taken from Longmore et al. (2011) for Mercer 5 and Borissova et al. (2007) for 2MASS GC02. The fundamental parameters of both clusters are calculated using the technique outlined in Ferraro et al. (2006), Valenti et al. (2005), and Valenti et al. (2007), which allows to determine the reddening, distance modulus, and a global photometric metallicity of a globular cluster from its near-infrared CMD. In this case, the RGB and HB clump calibrations were used. The targeted wavelength range was selected based on the line list published by Ryde et al. (2010) and covers a variety of iron and α-elements metal lines. It also has the advantage of being devoid of bright OH airglow lines, which aids the analysis of faint spectral features. The Phoenix configuration that was used is presented in Table 2. Note that the spectral coverage provided by Phoenix is limited by the size of the science array and is much smaller than the bandwidth of the H6420 order-sorting filter. 2.1. Red Giant Stars Sample Selection and Observations The stars observed in each cluster were selected on the basis of pre-existing near-IR CMDs and low-resolution spectroscopy (SofI/NTT, R ∼ 1500 and ISAAC @ VLT, R ∼ 500). All of them were identified as high-probability members of their host star clusters. The information about the individual stars observed is compiled in Table 3. We observed stars close to the tip of the red giant branch (TRGB) in order to ensure that the spectra will reach the required signal-to-noise ratio (S/N; ∼60) with a sensible investment of observing time. Figure 2 shows the positions of the target stars in the clusters, and on their color– magnitude diagrams. The J, H, and Ks images are taken from the Vista variables in the Via Lactea Survey (VVV, DR2, Saito et al. [2012])5 and UKIDS Galactic Plane Surveys (GPS, DR7)6 and the three-color images are constructed. The CMDs of the clusters are build using the photometric catalogs provided in VVV and GPS and include all objects residing into a 60″ radius. 5 6. http://horus.roe.ac.uk/vsa/. http://www.ukidss.org/index.html.. 2015 PASP, 127:329–339.

(3) CHEMICAL ABUNDANCES OF GALACTIC GLOBULAR CLUSTERS. 331. FIG. 1.—Illustration of the spatial distribution of the Milky Way globular clusters around the plane of the Galaxy. The two clusters targeted by the current study are marked and labeled. An elliptical projection of the Galactic coordinates was used with an all-sky image of the 2MASS stellar density set as a background. See the online edition of the PASP for a color version of this figure.. The spectra were acquired at Gemini South 8 m telescope during the semester 2010A (Program GS-2010A-Q-30, PI P. Pessev). Since our targets are relatively faint for such high spectral resolution (H ∼ 10–11), our observations took full advantage of the queue mode of operation, allowing us to impose exactly the required sky and seeing conditions during the data acquisition. A standard technique of ABBA offset pattern across the slit was used. Due to the crowded nature of the observed fields (see Fig. 2), we did a quick preimaging for the Phoenix acquisitions and provided detailed finder charts for the queue observers. Telluric standards, of spectral class A or earlier, from the Gemini calibration library were observed either before or/and after the observations at matching airmass to ensure proper reduction and calibration. Since standard stars are significantly brighter than the science targets, a larger offset along the slit (4″) was used with respect to that of the science data (2.5″). According to the. standard Gemini procedure, the exposure times for the tellurics were adjusted by the night observer (depending on the luminosity of the particular star and the observing conditions at the moment of the observation) to provide sufficient S/N for high-quality calibration. In general, the exposure times for the standards were much shorter with respect to those of the science targets. Flat fields were taken each time science data were acquired, before moving the grating or changing the instrument configuration, using the dedicated 100W GCAL calibration source. Phoenix darks with exposure times matching the flat field data were secured at the end of each night. The calibration dataset was completed by wavelength calibration frames acquired with the internal Phoenix ThAr lamp. Considering the significant investment of observing time required and taking into account the narrow wavelength coverage of Phoenix (that does not provide a favorable configuration of calibration lines on the detector), these were taken only for a fraction of the data as an extra wavelength reference cross-check.. TABLE 2 PHOENIX CONFIGURATION USED DURING THE OBSERVATIONS. 2.2. Data Reduction. Slit width Slit width Resolution (λ=Δλ) Central wavelength Wavelength coverage. The reduction of the spectra was carried out in the IRAF environment,7 using the standard procedure for Phoenix data.8. Width of the observed spectral region Filter used. 2015 PASP, 127:329–339. 4 pixels 0.34″ ∼50; 000 ∼15; 537:5 Å min. ∼15500:0 Å max. ∼15575:0 Å 75 Å H6420. 7 IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. 8 Available at: ftp://iraf.noao.edu/iraf/misc/phoenix.readme..

(4) 332. PEÑALOZA ET AL. TABLE 3 OBSERVING LOG Cluster ID (1). StarID (2). 2M GC02 2M GC02 Mercer 5 Mercer 5. Star Star Star Star. 1 4 1 2. AND INFORMATION. R.A. (3) 18 18 18 18. 09 09 23 23. 35.20 36.50 19.08 19.58. −20 −20 −13 −13. ABOUT. THE INDIVIDUAL. TARGETED STARS. Decl. (4). D cen. (arcseconds) (5). H (mag) (6). Date observed (7). Exposure time (s) (8). 47 46 40 40. 32.56 7.50 8.05 10.04. 10.7 9.7 9.9 9.1. 2010 Jun 4 UT 2010 Jun 7 UT 2010 Jul 2 UT 2010 Jun 7 UT. 7200 7200 3000 2400. 02.20 44.10 09.90 06.70. NOTES.—Columns (1) and (2) present the cluster and star ID, respectively, followed by the equatorial coordinates of the object [columns (3) and (4)]. Units of right ascension are hours, minutes, and seconds. Units of declination are degrees, minutes, and seconds. Column (5) shows the distance between the individual star and the center of the corresponding cluster. The H magnitude of the object is given in column (6). Columns (7) and (8) list the UT date of the observation and the total exposure time used for the observations.. standards to avoid spurious features affecting the final results. OH airglow lines were removed from both standard and science targets stellar spectra by subtracting each one of the ABBA pairs. Then the two-dimensional frames were divided by the normalized flat fields before the extraction of the individual spectra. The one-dimensional spectra were wavelengthcalibrated using atmospheric OH airglow lines. We targeted a spectral region that contains multiple interesting lines of iron and α-process elements, and is devoid of bright airglow features. This is particularly beneficial for the data reduction and the analysis of weak spectral lines, but poses significant challenges for the wavelength calibration. Most of the available. Here, we provide only a brief outline, with a focus on some crucial steps. First, we need to trim all the science and calibration frames. This is important because a small section of the detector array is delaminated, and the first ∼50 rows of each image are infested with a lot of bad pixels. Skipping that step will cause unnecessary complications during the entire data reduction process. Further, the flats and darks associated with each set of observations were combined and subtracted from the combined flats. The step of developing the normalized master flat for each set is particularly important in order to properly remove the features due to variations in the slit illumination. Normalization is also crucial for the reduction of the telluric. 8. Obj2 Obj1. 9 Obj1. Obj4 10. KS. 11. 12. 13. 14. 15 0. 1. 2. 3 J-KS. 4. 5. 1. 2. 3 J-KS. 4. 5. 6. FIG. 2.—Illustration of the spatial distribution of the targeted red giants into the clusters and their positions on the CMDs. Left: 10 × 10 three-color images of the fields of GC02 and Mercer 5, taken from Vista variables in the Via Lactea (VVV) and UKIDS Galactic Plane Surveys. Right: Color–magnitude diagrams of the GC02 and Mercer 5 cluster fields. The black points represent all objects residing into a 60″ radius; the observed objects are labeled. See the online edition of the PASP for a color version of this figure.. 2015 PASP, 127:329–339.

(5) CHEMICAL ABUNDANCES OF GALACTIC GLOBULAR CLUSTERS. 333. FIG. 3.—Observed spectra are shown with black crosses. Our best synthetic spectra are shown with a red line. Metal and molecular lines are indicated below the spectra. See the online edition of the PASP for a color version of this figure.. atlases of the OH airglow are not suitable for analysis of such high-resolution data, especially taking into account the width of the analyzed spectral region (see Table 2). Fortunately, the long exposures on the science targets allowed to identify five airglow features and assign the corresponding wavelengths using The Arcturus Atlas (telluric lines) obtained with Phoenix at Kitt Peak (Hinkle et al. 1995).9 The wavelength calibration solution was then cross-checked against the obtained arc lamp exposures. The telluric features in the final one-dimensional spectrum were corrected using the data for the corresponding standard stars. The resulting spectra for each of the stars in both 2MASS GC02 and Mercer 5 are presented on Figure 3. 2.3. Analysis of the Obtained Spectra Stellar spectra and chemical abundances were analyzed using the MOOG code (Sneden 1973). To perform the analysis, the program relies on stellar atmospheres models and line lists of the atomic and molecular species in the studied wavelength range. The model atmospheres were computed with the ATLAS9 9. Available at: ftp://cdsarc.u‑strasbg.fr/cats/J/PASP/107/1042/.. 2015 PASP, 127:329–339. Kurucz, R.L. (1993) code. Recently, significant progress was achieved on the availability of the high-resolution near-IR line lists, but it is still much more limited compared to the optical wavelength range. Pioneering works of Wallace et al. (1996) and Hinkle et al. (1995) focused on high-resolution, highsignal-to-noise spectra of the Sun and Arcturus. Current efforts are aimed at providing more uniform coverage across the HR diagram (see Lebzelter et al. 2012). Although this is a massive improvement over the earlier situation, more data and further studies are needed to match the optical spectral atlases for reference stars. The line list we used was kindly provided by N. Ryde (private communication). It covers 699 atomic and molecular lines in the 15,500–15,575 Å wavelength region (see Table 4), including iron lines, lines of α–elements, and molecular lines (CN and OH). MOOG computes synthetic spectra based input parameters, such as effective temperature, surface gravity, metallicity, microturbulence, and α-elements abundance. In order to determine the effective temperature, we used the photometry and lowresolution spectroscopy published by Borissova et al. (2002) and Borissova et al. (2007) for 2MASS GC02 and Longmore et al. (2011) for Mercer 5 in conjunction with the T eff :color:.

(6) 334. PEÑALOZA ET AL. TABLE 4 LINE LIST USED. No.. Wav. (Å). Elem.. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59. 15,500.073 15,500.241 15,500.316 15,500.345 15,500.650 15,500.708 15,500.800 15,501.003 15,501.080 15,501.080 15,501.320 15,501.345 15,501.354 15,501.511 15,501.787 15,501.833 15,502.170 15,502.239 15,502.261 15,502.294 15,502.429 15,502.434 15,502.549 15,502.564 15,502.576 15,502.640 15,502.836 15,502.934 15,503.043 15,503.246 15,503.246 15,503.441 15,503.840 15,503.943 15,503.967 15,503.994 15,504.083 15,504.126 15,504.554 15,505.107 15,505.326 15,505.350 15,505.524 15,505.526 15,505.591 15,505.747 15,505.771 15,505.782 15,505.846 15,505.849 15,506.052 15,506.079 15,506.099 15,506.105 15,506.246 15,506.246 15,506.252 15,506.363 15,506.408. ScI VII TiI CN MnI CN FeI CN CN FeI FeI CN OH CN CN CN FeI CN CN OH CoI CN CN CN CN SiI OH CN OH ScI CrI OH FeI CoI VI CN CN CN CN CN OH CN OH CN CN OH TiI OH CN OH OH CN OH FeI OH OH ScI CN CN. χexc (eV) No. 4.50 9.04 4.36 0.86 6.20 2.58 6.32 0.86 3.15 5.94 6.29 3.29 3.10 0.99 2.84 2.58 6.35 5.50 0.99 2.94 3.41 3.98 2.84 2.55 2.56 7.13 3.44 2.56 2.86 4.17 3.38 2.72 5.97 5.73 4.72 3.37 3.21 3.72 3.72 3.94 0.52 5.21 1.43 1.45 2.99 0.52 4.39 1.89 4.27 1.43 2.85 2.44 1.43 5.52 1.43 1.89 4.97 4.26 4.91. 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234. Wav. (Å). Elem.. 15,520.653 15,520.684 15,520.855 15,520.893 15,521.086 15,521.135 15,521.207 15,521.245 15,521.383 15,521.515 15,521.690 15,522.054 15,522.230 15,522.236 15,522.287 15,522.460 15,522.600 15,522.640 15,522.672 15,523.041 15,523.051 15,523.386 15,523.511 15,523.591 15,523.807 15,523.909 15,523.998 15,524.003 15,524.277 15,524.300 15,524.451 15,524.543 15,524.615 15,524.822 15,524.832 15,524.847 15,525.227 15,525.360 15,525.406 15,525.435 15,525.495 15,525.514 15,525.531 15,525.661 15,525.734 15,525.738 15,525.775 15,525.775 15,525.934 15,525.963 15,526.062 15,526.083 15,526.404 15,526.414 15,526.604 15,526.819 15,526.841 15,526.865 15,526.976. CN CN CN OH FeI CN CN CN CN CN FeI OH OH OH CN CN CoI FeI OH CN OH CN CN OH CN CN CoI CN NiI FeI CN FeI CN CN CN OH FeI CN CN CN CN CN CN VI TiII TiI OH CN CN CN CN CN CN CN CN CN CN CN CN. TO. MODEL OBSERVED SPECTRA. χexc (eV) No. 3.76 3.36 2.94 2.19 5.35 4.00 5.20 1.72 2.40 4.41 6.32 2.83 3.12 2.73 2.94 4.21 6.21 6.32 2.19 5.20 2.73 3.72 1.45 3.19 4.21 0.88 6.05 3.46 2.74 5.79 0.88 5.79 4.21 2.55 4.55 0.84 5.84 5.82 4.61 4.67 4.41 2.94 2.72 4.88 8.10 4.79 3.51 2.55 2.51 4.21 2.84 5.15 1.00 3.77 2.45 5.39 3.84 4.55 2.72. 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409. Wav. (Å). Elem.. 15,538.772 15,538.799 15,538.854 15,538.903 15,539.060 15,539.126 15,539.330 15,539.417 15,539.666 15,539.673 15,539.758 15,539.777 15,539.837 15,539.992 15,540.312 15,540.463 15,540.516 15,540.518 15,540.898 15,541.125 15,541.299 15,541.516 15,541.547 15,541.557 15,541.644 15,541.654 15,541.818 15,541.850 15,541.852 15,541.857 15,542.016 15,542.090 15,542.090 15,542.108 15,542.146 15,542.173 15,542.197 15,542.205 15,542.297 15,542.316 15,542.611 15,542.731 15,542.980 15,543.326 15,543.357 15,543.633 15,543.780 15,543.785 15,543.838 15,543.846 15,544.152 15,544.355 15,544.452 15,544.501 15,544.680 15,544.730 15,544.771 15,544.899 15,544.948. CN CN CN CN CN OH CN CrI CN CN CN CN CN CN OH CN CN CN CN CN CN CN FeI CN OH CN CN CN FeI FeI SiI SiI FeI CN OH CN TiI CN CN CN CN TiI CN CN TiI CN TiI OH TiI CN CuI TiI CN CN CN CN CN CN CN. χexc (eV) No. 3.75 4.15 2.89 2.53 4.13 0.79 4.25 5.96 2.53 4.42 3.29 5.82 0.88 5.16 3.48 3.98 0.88 3.77 4.96 4.04 3.98 5.73 5.84 3.83 0.89 4.42 3.58 1.26 5.97 6.37 7.01 7.01 5.64 0.83 0.89 4.13 4.69 5.20 1.91 5.12 5.08 4.39 1.20 4.00 4.86 4.05 1.88 0.84 4.79 3.58 6.79 2.49 2.72 1.15 2.79 2.86 4.00 4.47 2.51. 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584. Wav. (Å). Elem.. χexc (eV). 15,557.847 15,558.023 15,558.045 15,558.176 15,558.585 15,558.665 15,558.880 15,558.960 15,559.103 15,559.500 15,559.542 15,559.556 15,559.566 15,559.648 15,559.660 15,559.801 15,559.849 15,559.922 15,559.973 15,560.135 15,560.149 15,560.208 15,560.244 15,560.270 15,560.287 15,560.324 15,560.578 15,560.685 15,560.704 15,560.780 15,561.041 15,561.242 15,561.251 15,561.268 15,561.399 15,561.457 15,561.523 15,561.535 15,561.748 15,562.080 15,562.131 15,562.143 15,562.291 15,562.300 15,562.436 15,562.441 15,562.460 15,562.601 15,563.095 15,563.136 15,563.139 15,563.165 15,563.303 15,563.306 15,563.315 15,563.354 15,563.376 15,563.456 15,563.463. CN OH CN CN TiI CN CN CN CN NiI CN CN CN CN CN CN FeI CaI CN CN CN CN OH CN CN CN CN CN CN FeI CoI CN SiI FeI CN CN CN CN CN VI CN CN CN NiI CN CN CN OH OH CN OH CN CN CN CN CN CN CN CrI. 2.65 0.30 0.91 2.66 4.50 0.73 2.64 2.87 2.42 5.87 1.01 2.67 1.00 1.01 1.00 1.00 5.93 5.17 0.99 2.51 1.01 1.00 0.30 1.01 1.00 3.71 1.00 2.51 2.64 6.35 6.08 3.72 7.04 6.71 1.01 1.00 1.00 1.01 2.68 4.63 4.25 2.50 1.15 6.37 6.54 2.50 6.32 2.77 2.77 3.58 2.75 4.29 1.00 1.02 2.63 1.00 1.15 1.02 5.24. 2015 PASP, 127:329–339.

(7) CHEMICAL ABUNDANCES OF GALACTIC GLOBULAR CLUSTERS. 335. TABLE 4 (Continued) No.. Wav. (Å). Elem.. 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119. 15,506.685 15,506.779 15,506.901 15,506.969 15,506.980 15,507.022 15,507.043 15,507.046 15,507.046 15,507.048 15,507.103 15,507.118 15,507.156 15,507.180 15,507.241 15,507.332 15,507.500 15,507.623 15,507.816 15,507.844 15,508.075 15,508.385 15,508.393 15,508.477 15,508.670 15,508.677 15,508.718 15,508.799 15,509.016 15,509.507 15,509.526 15,509.779 15,509.863 15,510.178 15,510.358 15,510.648 15,510.717 15,510.847 15,511.088 15,511.117 15,511.528 15,511.665 15,511.769 15,511.810 15,512.147 15,512.291 15,512.575 15,512.635 15,512.724 15,512.761 15,512.771 15,512.891 15,513.146 15,513.208 15,513.336 15,513.367 15,513.468 15,513.477 15,513.511 15,513.675. CN CN CN CN SiI VI PI CN CN CN TiI FeII CN CN CN CN CN TiI CN CN CN TiI CN CN OH CN CN CN CN CN CN CN CN CN OH OH CN CN CN SiI FeI CN CN CN CN CN OH CN VI CN OH CN CN CN CN CN OH OH TiI CN. χexc (eV) No.. 2015 PASP, 127:329–339. 2.71 1.45 6.39 5.52 6.73 4.87 8.23 1.00 3.21 2.99 4.77 8.94 0.89 2.71 0.71 5.21 4.49 5.24 2.38 0.89 2.64 4.77 4.80 1.22 1.89 6.07 2.64 0.97 3.46 2.48 0.97 2.48 2.70 4.20 1.89 0.26 3.46 2.72 4.20 7.17 5.48 5.73 5.52 0.88 3.62 2.37 0.86 4.60 4.68 2.48 0.86 0.82 5.31 1.12 2.67 3.54 0.92 0.26 4.51 1.06. 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294. Wav. (Å). Elem.. 15,527.043 15,527.210 15,527.323 15,527.325 15,527.465 15,527.470 15,527.513 15,527.535 15,527.564 15,527.629 15,527.713 15,527.837 15,527.890 15,528.109 15,528.121 15,528.128 15,528.160 15,528.218 15,528.365 15,528.575 15,528.577 15,528.589 15,528.599 15,528.618 15,528.631 15,528.670 15,528.768 15,528.891 15,528.903 15,528.915 15,528.994 15,528.994 15,529.105 15,529.168 15,529.226 15,529.243 15,529.316 15,529.344 15,529.453 15,529.657 15,529.662 15,529.773 15,529.846 15,529.913 15,529.928 15,530.010 15,530.043 15,530.080 15,530.162 15,530.186 15,530.195 15,530.205 15,530.316 15,530.654 15,530.683 15,530.810 15,531.103 15,531.124 15,531.280 15,531.494. CN FeI CN CN CN CN CN SiI CN CN OH CN CN FeI OH CN CN CN CN CN CN CN CN CN OH OH CN CN CN CN CN CN CN CN CN CN OH CN CN OH CN CN CN CN CN CN FeI CN CN CN VI CN CN CN CN CN OH OH TiI CN. χexc (eV) No. 3.15 6.32 3.90 3.84 2.57 2.94 3.94 7.14 4.61 4.55 2.89 2.57 4.42 5.95 1.35 4.92 2.96 1.00 4.88 2.72 4.35 2.67 4.67 3.77 3.06 3.21 3.94 4.41 2.94 3.15 1.00 3.06 4.92 2.96 5.84 2.77 3.06 4.61 2.72 3.48 4.55 3.15 4.67 1.25 2.67 2.64 3.57 0.89 2.65 2.51 5.45 3.06 2.77 2.64 4.30 0.89 3.29 2.94 4.65 4.84. 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469. Wav. (Å). Elem.. 15,545.047 15,545.332 15,545.409 15,545.511 15,545.584 15,545.668 15,545.782 15,546.081 15,546.089 15,546.488 15,546.531 15,546.709 15,546.780 15,546.790 15,546.818 15,546.838 15,546.848 15,546.920 15,547.041 15,547.940 15,548.190 15,548.349 15,548.422 15,548.480 15,548.487 15,548.673 15,548.908 15,548.914 15,548.978 15,549.206 15,549.501 15,549.541 15,549.554 15,549.736 15,549.786 15,549.803 15,549.902 15,549.948 15,550.226 15,550.320 15,550.357 15,550.381 15,550.450 15,550.553 15,550.560 15,550.623 15,550.645 15,550.867 15,550.949 15,550.964 15,550.981 15,551.172 15,551.430 15,551.636 15,551.714 15,551.818 15,551.861 15,552.108 15,552.222 15,552.254. CN CN CN CN CN CN CN TiI CN CN CN OH CN CN OH CN CN CN CN OH CN CN CN CN OH CN CN OH CaI CN CN OH CN OH CN CN OH CN CN CN CN CN FeI CN FeI CN CN CN CN CN CN CN FeI CN CN VI CN TiII FeI OH. χexc (eV) No. 4.41 2.72 5.63 2.86 1.15 5.82 1.22 4.41 2.60 2.60 4.47 3.48 2.83 4.47 2.75 1.22 5.44 1.55 4.21 1.56 0.99 3.67 4.47 3.89 3.66 2.87 2.61 0.93 5.18 3.19 3.90 2.59 2.83 2.18 3.90 4.03 0.73 2.87 4.10 2.66 4.03 0.89 6.34 2.65 6.11 3.19 2.96 3.90 0.89 3.06 2.66 5.44 6.35 2.89 4.14 4.66 2.65 8.11 5.62 2.74. 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644. Wav. (Å). Elem.. χexc (eV). 15,563.778 15,563.902 15,564.020 15,564.185 15,564.268 15,564.369 15,564.684 15,564.723 15,564.769 15,564.793 15,564.938 15,565.230 15,565.256 15,565.336 15,565.356 15,565.390 15,565.448 15,565.588 15,565.644 15,565.734 15,565.770 15,565.817 15,565.838 15,565.879 15,565.886 15,565.962 15,565.996 15,566.044 15,566.051 15,566.255 15,566.274 15,566.393 15,566.603 15,566.703 15,566.725 15,566.907 15,566.941 15,567.001 15,567.014 15,567.188 15,567.261 15,567.530 15,567.552 15,567.575 15,567.680 15,567.704 15,567.724 15,567.728 15,567.869 15,568.180 15,568.187 15,568.325 15,568.383 15,568.567 15,568.614 15,568.650 15,568.744 15,568.764 15,568.780 15,568.853. CN CN FeII CN CN FeI CN ScI CN CN OH FeI CN CN CN CN CN CN CN CN CN OH OH CN VI OH OH CN CN CN CN CN OH CN FeI CN CN ScI CN SiI FeI CN OH OH VI CN CN VI CN CN SiI FeI VI CN CN CN CN CN OH OH. 2.46 2.79 9.05 4.25 2.75 5.61 2.73 4.53 2.69 2.75 0.78 6.32 2.58 2.42 0.91 4.05 1.76 5.35 2.79 0.99 0.99 0.90 3.66 1.02 4.64 2.78 0.90 1.02 5.16 4.12 6.40 4.96 2.68 2.63 6.35 4.50 3.84 4.97 3.94 7.11 6.35 6.42 3.00 0.73 4.62 5.16 3.84 4.59 2.55 1.29 7.11 5.88 4.67 4.96 2.69 2.45 0.99 0.99 0.30 3.29.

(8) 336. PEÑALOZA ET AL. TABLE 4 (Continued). No.. Wav. (Å). Elem.. 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175. 15,513.800 15,514.195 15,514.270 15,514.280 15,514.427 15,514.496 15,514.691 15,514.802 15,514.891 15,515.117 15,515.368 15,515.373 15,515.416 15,515.445 15,515.617 15,515.768 15,515.777 15,515.797 15,515.876 15,515.931 15,515.969 15,516.151 15,516.284 15,516.418 15,516.537 15,516.660 15,516.720 15,517.095 15,517.228 15,517.275 15,517.367 15,517.487 15,517.815 15,518.135 15,518.166 15,518.289 15,518.395 15,518.670 15,518.675 15,518.708 15,518.720 15,518.764 15,518.793 15,518.829 15,518.900 15,519.065 15,519.084 15,519.100 15,519.360 15,519.600 15,519.636 15,519.942 15,519.949 15,520.115 15,520.154 15,520.262. OH CN CN FeI OH CN SiI CN CN OH TiI VI CN OH OH FeI CN CN TiI CN OH CN OH CN OH OH FeI CN OH CoI CN CN CN CN CN CN CN CN CN CN ScI CN CN CN FeI CN CN FeI FeI CN VI FeI ScI SiI CN CN. χexc (eV) No. 0.92 2.53 1.12 6.29 3.12 1.06 7.09 1.33 1.52 2.21 2.31 4.65 2.38 2.18 2.18 6.29 2.50 1.33 4.79 1.18 3.06 4.82 2.83 1.00 3.29 2.89 6.29 2.77 2.85 5.74 1.20 3.29 4.35 2.49 2.77 2.58 1.20 2.49 2.58 4.14 5.10 4.04 1.23 5.07 6.28 3.29 3.36 6.29 6.29 3.61 4.11 2.48 3.81 7.11 5.37 4.41. 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350. Wav. (Å). Elem.. 15,531.503 15,531.646 15,531.713 15,531.750 15,532.116 15,532.263 15,532.449 15,532.536 15,532.802 15,533.347 15,533.389 15,533.710 15,533.849 15,533.977 15,534.020 15,534.081 15,534.182 15,534.260 15,534.306 15,534.368 15,534.399 15,534.455 15,534.602 15,534.665 15,534.892 15,534.986 15,535.167 15,535.182 15,535.317 15,535.329 15,535.353 15,535.462 15,535.498 15,535.602 15,535.816 15,535.829 15,536.224 15,536.642 15,536.706 15,536.773 15,536.895 15,536.997 15,537.181 15,537.207 15,537.227 15,537.253 15,537.410 15,537.450 15,537.572 15,537.690 15,537.777 15,538.060 15,538.081 15,538.084 15,538.434 15,538.463. CN CN CN FeI CN SiI SiI CN OH CN OH OH CN SiI CN CN CN FeI OH CN CN CN CN CN CN CN CN CN CN CN CN OH CN CN CN CN CN CN OH CN OH CN OH OH CN CN OH FeI FeI FeI CN CoI CN CN OH SiI. χexc (eV) No. 4.61 3.15 3.12 5.64 4.35 7.14 6.72 4.29 3.48 4.29 1.35 2.33 0.99 7.14 3.67 4.29 3.36 5.64 0.84 3.68 2.45 2.83 0.99 4.13 4.29 2.73 1.33 4.27 2.49 3.91 5.50 0.51 2.73 2.49 1.06 0.90 4.92 1.06 0.51 2.71 3.44 0.99 0.84 0.78 3.67 3.27 0.48 5.79 5.79 6.32 4.13 5.74 0.76 5.20 0.48 6.76. 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 484 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525. Wav. (Å). Elem.. 15,552.268 15,552.747 15,552.769 15,552.885 15,553.245 15,553.313 15,553.340 15,553.560 15,553.577 15,553.659 15,553.727 15,554.146 15,554.446 15,554.501 15,554.510 15,554.510 15,554.557 15,554.603 15,554.625 15,554.697 15,554.855 15,554.939 15,555.112 15,555.120 15,555.138 15,555.210 15,555.370 15,555.641 15,555.700 15,555.720 15,555.750 15,555.765 15,555.835 15,556.016 15,556.058 15,556.106 15,556.115 15,556.122 15,556.384 15,556.593 15,556.670 15,556.711 15,556.919 15,556.939 15,556.962 15,557.006 15,557.006 15,557.212 15,557.387 15,557.447 15,557.602 15,557.607 15,557.684 15,557.689 15,557.735 15,557.790. CN CN CN CN VII CN CN FeI CN CN CN CN OH CN FeI FeI TiI CN VI VII CN OH OH NiI CN NiI NiI ScI CN CN CN OH CN NiI CN OH OH CuI CN CN FeI TiI CN CN OH CN CN OH CN CN VI CN CN TiI CN SiI. χexc (eV) No. 3.89 0.90 3.89 4.14 5.54 4.14 2.58 5.48 2.89 1.08 2.58 4.41 0.79 1.08 6.28 6.28 4.43 1.28 4.61 5.87 5.01 2.75 3.66 5.28 4.50 5.28 5.49 5.06 1.02 1.36 1.49 1.50 4.14 5.28 4.04 1.50 1.49 6.55 4.30 1.02 5.93 5.30 4.04 1.36 1.50 3.74 4.14 1.57 1.49 3.74 4.68 2.66 2.87 5.28 2.96 5.96. 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699. Wav. (Å). Elem.. χexc (eV). 15,568.955 15,568.980 15,569.103 15,569.135 15,569.240 15,569.314 15,569.486 15,569.490 15,569.576 15,569.741 15,569.903 15,569.911 15,569.984 15,570.044 15,570.073 15,570.202 15,570.306 15,570.575 15,570.752 15,570.861 15,571.055 15,571.099 15,571.120 15,571.152 15,571.220 15,571.417 15,571.511 15,571.664 15,571.729 15,571.740 15,571.822 15,571.834 15,571.897 15,572.084 15,572.166 15,572.217 15,572.230 15,572.312 15,572.334 15,572.484 15,572.632 15,572.651 15,573.083 15,573.261 15,573.277 15,573.294 15,573.466 15,573.673 15,573.724 15,573.821 15,573.976 15,574.060 15,574.599 15,574.667 15,574.837. CN CN SiI CN FeI CN CN OH CN CoI CN CN OH CN CN NiII CN CN CN CN CN VI FeI CN CN CN CN CN VI FeI CN CN CN OH ScI CN OH CN CN CN TiI VI CN CN CN CN CN CN CN CN CrI FeI CN CN CN. 2.86 4.50 7.11 1.03 5.51 1.03 4.21 0.84 4.74 5.75 2.61 2.40 2.78 3.81 3.70 8.42 3.10 3.41 5.08 2.62 2.61 4.68 5.88 1.22 3.19 4.21 5.35 5.41 2.58 6.32 2.66 3.82 3.10 0.30 5.54 5.08 3.19 0.84 0.99 2.66 4.67 4.65 1.03 1.49 1.03 2.70 3.90 2.53 5.50 4.68 5.94 6.31 2.42 5.85 2.61. NOTE.—The wavelength is in air; the excitation energy is of the lower level.. 2015 PASP, 127:329–339.

(9) CHEMICAL ABUNDANCES OF GALACTIC GLOBULAR CLUSTERS. 337. TABLE 5 STELLAR PARAMETERS. AND. DERIVED ABUNDANCES. Mercer 5 Object:. 2MASS GC02. 1. 2. 1. 4. T eff (K) log gðcm s2 Þ ξ micro ðkm s2 Þ ½α=Fe (dex) [Fe/H] (dex). 3650 ± 100 0.5 ± 0.2 2.0 ± 0.5 0.40 −0.90 ± 0.13. 4000 ± 100 1.0 ± 0.2 1.9 ± 0.5 0.40 −1.10 ± 0.14. 4050 ± 100 1.0 ± 0.2 1.9 ± 0.5 0.40 −1.05 ± 0.14. [N/Fe] (dex) [O/Fe] (dex) [Si/Fe] (dex) [Ti/Fe] (dex) [Ni/Fe] (dex). +0.45 +0.30 +0.50 +0.30 +0.30. ± ± ± ± ±. 0.09 0.11 0.14 0.17 0.17. +0.53 +0.12 +0.03 +0.20 +0.20. ± ± ± ± ±. 0.10 0.12 0.15 0.17 0.17. +0.43 ± 0.10 +0.33 ± 0.12 0.00 ± 0.15 +0.35 ± 0.17 +0.10 ± 0.17. [N/Fe] (dex) [O/Fe] (dex) [Si/Fe] (dex) [Ti/Fe] (dex) [Ni/Fe] (dex). +0.65 +0.30 +0.50 +0.40 +0.30. ± ± ± ± ±. 0.10 0.10 0.14 0.17 0.17. +0.75 +0.10 +0.05 +0.30 +0.15. ± ± ± ± ±. 0.10 0.12 0.15 0.17 0.17. +0.70 +0.35 +0.02 +0.35 +0.10. [N/Fe] (dex) [O/Fe] (dex) [Si/Fe] (dex) [Ti/Fe] (dex) [Ni/Fe] (dex). +0.90 +0.30 +0.50 +0.40 +0.30. ± ± ± ± ±. 0.10 0.10 0.14 0.17 0.17. 3680 ± 100 0.5 ± 0.2 2.0 ± 0.5 0.40 −0.80 ± 0.14 ½C=Fe ¼ 0:15 dex +0.65 ± 0.10 +0.30 ± 0.11 +0.55 ± 0.14 +0.48 ± 0.17 +0.25 ± 0.17 ½C=Fe ¼ 0:35 dex +0.95 ± 0.10 +0.32 ± 0.11 +0.55 ± 0.14 +0.48 ± 0.17 +0.25 ± 0.17 ½C=Fe ¼ 0:55 dex +1.15 ± 0.11 +0.32 ± 0.11 +0.55 ± 0.14 +0.48 ± 0.17 +0.25 ± 0.17. +1.03 +0.15 +0.03 +0.20 +0.15. ± ± ± ± ±. 0.10 0.11 0.15 0.17 0.17. +0.90 ± 0.10 +0.30 ± 0.11 0.00 ± 0.15 +0.40 ± 0.17 +0.10 ± 0.17. [Fe/H] calibrations of Ramírez & Meléndez (2005) for giant stars. The initial effective temperatures used were 4000 K for the 2MASS GC02 stars and 3600 K for Mercer 5. Surface gravity (log g) has been estimated from theoretical evolutionary tracks using the location of the stars on the red giant branch (Origlia et al. 1997). We performed spectral synthesis on suitable Fe I and Fe II lines to derive the metallicity. The microturbulence velocity is set to a value typical for red giant stars (ξ micro ½km s1 ¼ 2:13–0:23 log g) as given in Kirby et al. (2009). The adopted ½α=Fe ¼ 0:40 is set in accordance with Gonzalez et al. (2011). Their results are based on the analysis of 650 giants in the different sections of the Galactic bulge. To fit the widths and shapes of the lines of the observed spectra, each synthetic spectrum was convolved with a Gaussian function and macroturbulence function, and the abundance is allowed to vary until the best fit is identified. The selected spectral range gives a reasonable number of atomic and molecular lines not affected by blending to derive relative abundances (see Fig. 3). Unfortunately, it does not cover CO molecular lines. Therefore, we adopted three values of ½C=Fe ¼ 0:15, 0:35, and 0:55 in accordance with the results of Ryde et al. (2009) and Ryde et al. (2010). The total abundance errors were determined by varying each of the input stellar parameters by its estimated errors and adding in quadrature the resulting abundance variations (see Table 5). We estimate the typical uncertainties of ΔT eff 100 K, Δ log g 0:2 dex, Δξ micro 0:5 km s1 , which translates into abundance errors for Fe ∼ 0:14,. 2015 PASP, 127:329–339. ± ± ± ± ±. 0.10 0.12 0.15 0.17 0.17. N ∼ 0:10, O ∼ 0:11, Si ∼ 0:14, Ti ∼ 0:17, and Ni ∼ 0:17, respectively. 3. RESULTS Figure 3 shows our best-fitting synthetic spectra superimposed on the observed spectra of the target giants in both globular clusters. The derived stellar parameters and element abundances are summarized in Table 5. By definition: ½X=Fe ¼ ½logðXÞ– logðFeÞstar –½logðXÞ– logðFeÞ⊙ logðXÞ ¼ log nX =nH þ 12. (1) (2). where log nX is the number density of element X. As mentioned before, the observed spectral interval does not cover the CO molecular lines, hence we can not derive C abundance. To approach this we estimate the [N/Fe], [O/Fe], [Si/Fe], [Ti/Fe], and [Ni/Fe] abundances for three distinct [C/Fe] values, consistent with the range reported for 14 red giants in the Galactic bulge by Ryde et al. (2009) and Ryde et al. (2010). As evident from the table, taking into account the uncertainties, most of the estimates for the individual giants are in agreement and only the [N/Fe] is affected by variations of [C/Fe]. In Table 6, we present the mean [O/Fe], [Si/Fe], [Ti/Fe], and [Ni/Fe] abundances for each observed giant in Mercer 5 and 2MASS GC02 based on three estimates per star ([Fe/H] values for each star are also listed ). For each cluster, [Fe/H] is calculated as the.

(10) 338. PEÑALOZA ET AL. TABLE 6 DERIVED ABUNDANCES. FOR. BOTH CLUSTERS. Mercer 5 Object 1 [Fe/H] [O/Fe] [Si/Fe] [Ti/Fe] [Ni/Fe]. −0.90 0.30 0.50 0.37 0.30. ± ± ± ± ±. 0.13 0.11 0.14 0.17 0.17. Object 2 −0.80 0.31 0.55 0.48 0.25. ± ± ± ± ±. 0.14 0.11 0.14 0.17 0.17. 2MASS GC02 Mean −0.86 0.31 0.53 0.42 0.28. ± ± ± ± ±. Object 1 0.14 0.11 0.14 0.17 0.17. −1.10 0.15 0.04 0.23 0.17. ± ± ± ± ±. 0.14 0.12 0.15 0.17 0.17. Object 4 −1.05 0.33 0.00 0.37 0.10. ± ± ± ± ±. 0.14 0.12 0.15 0.17 0.17. Mean −1.08 0.23 0.02 0.30 0.13. ± ± ± ± ±. 0.13 0.12 0.15 0.17 0.17. NOTE.—The mean [O/Fe], [Si/Fe], [Ti/Fe], and [Ni/Fe] abundances for each observed giant in Mercer 5 and 2MASS GC02 are based on three estimates per star, ([Fe/H] values for each star are also listed ). For each cluster, [Fe/H] is calculated as the mean for the two giants; [O/Fe], [Si/Fe], [Ti/Fe], and [Ni/Fe] are the mean of the six individual estimates.. mean for the two giants, and [O/Fe], [Si/Fe], [Ti/Fe], and [Ni/ Fe] are the mean of all the individual estimates. The uncertainties of the individual measurements were used to calculate the corresponding weights. The uncertainties reported in the table represent a conservative estimate, taking into account observational uncertainties, errors of calibrations, transformations, and determination of the atmospheric parameters. To compare our determinations with the abundance rations measured by previous authors, we selected four bulge globular clusters: NGC 6522 (Barbuy et al. 2014); NGC 6569 and NGC 6624 (Valenti et al. 2011); and Terzan 1 (Valenti et al. 2015); as. FIG. 4.—Top to bottom: Ratios of O, Si, and Ti to Fe. The dark circles stand for NGC 6522 red giant stars; blue, green, and pink circles are for NGC 6569, NGC 6624, and Terzan 1 red giants; the Mercer 5 and 2MASS GC02 red giant abundance ratios from this article are presented as red circles and are labeled. See the online edition of the PASP for a color version of this figure.. well as the abundance measurements of 264 red giant stars in three bulge fields taken from Johnson et al. (2013). The results are shown in Figures 4 and 5. As can be seen from the plots, the two measured stars of Mercer 5 follow the general trend of both bulge field and cluster stars at this metallicity. Indeed, their [O/Fe], [Si/Fe], and [Ti/Fe] ratios are enhanced by ≥ þ 0:3. The 2MASS GC02 stars have relatively lower ratios, but still compatible with other bulge clusters. Therefore, abundance ratios alone would not allow us to confirm that these two objects are indeed bound globular clusters. On the other hand, the bulge metallicity distribution is populated only very sparsely at ½Fe=H ∼ 1:0, therefore if those four were just bulge field stars, the probability of having all of them as metal-poor is virtually zero. Hence, we confirm the cluster nature of both Mercer 5 and 2MASS GC02.. FIG. 5.—[O/Fe] and [Si/Fe] abundance rations of Mercer 5 (blue stars) and 2MASS GC02 (red stars) objects overplotted on Fig. 18 of Johnson et al. (2013). The black circles are abundance rations of 264 red giants of three combined bulge fields; the solid red line shows the predicted change in each α-element as a function of [Fe/H], based on the bulge model of Kobayashi et al. (2011). The dashed green line is the model prediction assuming a flatter IMF (x ¼ 0:3) and the dotted blue line is the model prediction assuming x ¼ 0:3 with outflow (see Johnson et al. [2013] for details). See the online edition of the PASP for a color version of this figure.. 2015 PASP, 127:329–339.

(11) CHEMICAL ABUNDANCES OF GALACTIC GLOBULAR CLUSTERS 4. SUMMARY We present the first chemical abundance estimates of two newly discovered Galactic globular clusters, residing in the direction of the bulge in regions of high interstellar reddening. [Fe/H] for 2MASS GC02 is in agreement with earlier estimate by Borissova et al. (2007), based on moderate-resolution nearIR spectroscopy in the K band. The metallicity for Mercer 5 is significantly higher than the value derived by Longmore et al. (2011) using SofI/NTT moderate-resolution spectra. Based on these results, we conclude that both Mercer 5 and 2MASS GS02 are two intermediate metal-rich bulge globular clusters, with iron abundances of ½Fe=H ¼ 0:86 and ½Fe=H ¼ 1:08, respectively. The [O/Fe], [Si/Fe], and [Ti/Fe] abundance ratios of Mercer 5 are enhanced by ≥ þ 0:3 with respect to the solar value, while the two observed giants of 2MASS GC02 show lower ratios. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with. 339. the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). This paper is based on observations obtained with the Phoenix infrared spectrograph, developed and operated by the National Optical Astronomy Observatory. The data were acquired as part of science program GS-2010A-Q-30 and 179.B-2002,VIRCAM, VISTA at ESO, Paranal Observatory. Support for J. B., R. K., S. V., and M. Z. is provided by the Ministry of Economy, Development, and Tourism’s Millennium Science Initiative through grant IC12009, awarded to The Millennium Institute of Astrophysics (MAS) and Fondecyt Reg. Nos. 1120601 and 1110393. We acknowledge technical assistance by B. Idahl (CTIO REU 2013 program) on Figure 1. The authors are grateful to the anonymous referee for the constructive comments that improved the paper. Facilities: Gemini South (Phoenix).. REFERENCES Abazajian, K. N., et al. 2009, ApJS, 182, 543 Alonso-García, J., Dékény, I., Catelan, M., Contreras Ramos, R., Gran, F., Amigo, P., Leyton, P., & Minniti, D. 2015, AJ, 149, 99 Barbuy, B., et al. 2014 A&A, 570, 76 Benjamin, R. A., et al. 2003, PASP, 115, 953 Bica, E., Bonatto, C., Ortolani, S., & Barbuy, B. 2007, A&A, 472, 483 Bonatto, C., Bica, E., Ortolani, S., & Barbuy, B. 2007, MNRAS, 381, L 45 Borissova, J., Ivanov, V. D., & Vanzi, L. 2002, Extragalactic Star Clusters, 207, 107 Borissova, J., et al. 2007, A&A, 474, 121 Ferraro, F., Valenti, E., & Origlia, L. 2006, AJ, 649, 243 Froebrich, D., Meusinger, H., & Davis, C. J. 2008, MNRAS, 383, L 45 Gonzalez, O. A., et al. 2011, A&A, 530, A 54 Harris, W. E. 1996, AJ , 112, 1487 Hinkle, K., Wallace, L., & Livingston, W. 1995, PASP, 107, 1042 Hinkle, K. H., et al. 1998, Proc. SPIE, 3354, 810 Hurt, R. L., et al. 2000, AJ, 120, 1876 Johnson, C. I., et al. 2013 ApJ, 765, 157 Kirby, E., Guhathakurta, P., Bolte, M., Sneden, C., & Geha, M. C. 2009, ApJ, 705, 328 Kobayashi, C., Karakas, A. I., & Umeda, H. 2011, MNRAS, 414, 3231 Kurucz, R. L. 1993, Kurucz CD-ROM 13, Atlas 9 Stellar Atmosphere Programs and 2 km=s Grid (Cambridge: SAO) Lebzelter, T., et al. 2012, A&A, 539, A 109. 2015 PASP, 127:329–339. Longmore, A. J., et al. 2011, MNRAS, 416, 465 Mercer, E. P., et al. 2005, ApJ, 635, 560 Minniti, D., et al. 2010, NewA, 15, 433 ———. 2011, A&A, 527, A 81 Moni Bidin, C., et al. 2011, A&A, 535, A 33 Origlia, L., Ferraro, F. R., Fusi Pecci, F., & Oliva, E. 1997, A&A, 321, 859 Ortolani, S., Bonatto, C., Bica, E., & Barbuy, B. 2009, AJ, 138, 889 Ortolani, S., Bonatto, C., Bica, E., Barbuy, B., & Saito, R. K. 2012, AJ, 144, 147 Ramírez, I., & Meléndez, J. 2005, ApJ, 626, 465 Ryde, N., et al. 2009, A&A, 496, 701 ———. 2010, A&A, 509, A 20 Saito, R. K., et al. 2012, A&A, 537, A 107 Sakamoto, T., & Hasegawa, T. 2006, ApJ, 653, L 29 Skrutskie, M. F., et al. 2006, AJ, 131, 1163 Sneden, C. 1973, ApJ, 184, 839 Valenti, E., Ferraro, F. R., & Origlia, L. 2007, ApJ, 133, 1287 Valenti, E., Origlia, L., & Ferraro, F. R. 2005, MNRAS, 361, 272 Valenti, E., Origlia, L., Mucciarelli, A., & Rich, R. M. 2015, A&A, 574, A80 Valenti, E., Origlia, L., & Rich, R. M. 2011, MNRAS, 414, 2690 Wallace, L., Livingston, W., Hinkle, K., & Bernath, P. 1996, ApJS, 106, 165.

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