arXiv subjects

A. F. Marino

Publications and source records attributed to A. F. Marino.

At least 37 records · Page 2Linked to original sources

arXiv2025

Exploring Multiple Stellar Populations in Globular Clusters with Euclid: A Theoretical Overview and Insights from NGC 6397

We investigate the behavior of multiple stellar populations in globular clusters (GCs) using photometric diagrams constructed with Euclid photometry. By employing synthetic spectra and isochrones that incorporate the chemical differences between first-population (1P) stars, resembling field stars, and second-population (2P) stars, enriched in helium and nitrogen but depleted in carbon and oxygen, we identify, from a theoretical perspective, the color-magnitude diagrams and the chromosome maps most effective at distinguishing these populations within GCs. Euclid photometry proves to be a powerful tool for identifying multiple populations among M-dwarfs, as 1P and 2P stars form distinct sequences in well-chosen photometric diagrams, driven by differences in the strength of oxygen-based molecular features, such as water vapor. To validate our theoretical findings, we analyzed Euclid photometry and astrometry of the GC NGC 6397, complemented by photometric and astrometric data from the Hubble Space Telescope and James Webb Space Telescope, enabling a comprehensive study of its stellar populations across a wide field of view. We find that the 1P constitutes about 30% of the M-dwarfs in NGC 6397, with the fraction of 1P stars remaining consistent across different stellar masses and throughout the entire field of view. 2P stars exhibit an [O/Fe] depletion of about 0.3 dex relative to 1P stars, and both populations display isotropic proper motions. This study represents the first comprehensive analysis of multiple populations among M-dwarfs across a wide field of view, demonstrating that Euclid photometry is a powerful instrument for investigating multiple populations in GCs.

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arXiv2025

Exploring the formation environment of multiple stellar populations in Globular Clusters through binary systems

Globular Clusters (GCs) are known to host distinct stellar populations, characterized by different chemical compositions. Despite extensive research, the origin of these populations remains elusive. According to many formation scenarios, the second population (2P) originated within a compact and denser region embedded in a more extended first population (1P) system. As a result, 2P binaries should be disrupted at a larger rate than 1P binaries. For this reason, binary systems offer valuable insight into the environments in which these stellar populations formed and evolved. In this research, we analyze the fraction of binaries among 1P and 2P M dwarfs in the outer region of NGC 288 using Hubble Space Telescope data. We combine our results with those from a previous work, where we inferred the fraction of 1P and 2P binaries in the cluster center. In the outer region, we find a predominance of 1P binaries ($97^{+1}_{-3}\%$) compared to 2P binaries ($3\pm1\%$) corresponding to an incidence of binaries with a mass ratio (i.e., the ratio between the masses of the primary and secondary star) greater than 0.5 equal to $6.4\pm 1.7\%$ for the 1P population and $0.3\pm 0.2\%$ for the 2P population. These binary fractions and incidences differ from those found in the cluster$'$s central region, where the 1P and 2P populations exhibit similar binary incidences and fractions. These results are in general agreement with the predictions of simulations following the evolution of binary stars in multiple-population GCs, starting with a dense 2P subsystem concentrated in the central regions of a 1P system.

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arXiv2025

Mass loss along the red giant branch of the intermediate stellar populations in NGC6752 and NGC2808

The morphology of the Horizontal Branch (HB) in Globular Clusters (GC) is among the early evidences that they contain multiple populations of stars. Indeed, the location of each star along the HB depends both on its initial helium content (Y) and on the global average mass loss along the red giant branch ($μ$). In most GCs, it is generally straightforward to analyse the first stellar population (standard Y), and the most extreme one (largest Y), while it is more tricky to look at the "intermediate" populations (mildly enhanced Y). In this work, we do this for the GCs NGC6752 and NGC2808; wherever possible the helium abundance for each stellar populations is constrained by using independent measurements present in the literature. We compare population synthesis models with photometric catalogues from the Hubble Space Telescope Treasury survey to derive the parameters of these HB stars. We find that the location of helium enriched stars on the HB is reproduced only by adopting a higher value of $μ$ with respect to the first generation stars in all the analysed stellar populations. We also find that $μ$ correlates with the helium enhancement of the populations. This holds for both clusters. This finding is naturally predicted by the model of ''pre-main sequence disc early loss'', previously suggested in the literature, and is consistent with the findings of multiple-populations formation models that foresee the formation of second generation stars in a cooling flow.

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arXiv2025

New perspective on the multiple population phenomenon in Galactic globular clusters from a wide-field photometric survey

Wide-field photometry of Galactic globular clusters (GCs) has been investigated to overcome limitations from the small field of view of the Hubble Space Telescope in the study of multiple populations. In particular, 'chromosome maps' (ChMs) built with ground-based photometry were constructed to identify the first and second generation stars (1G and 2G) over the wide-field of view. The ChMs allow us to derive the fraction of distinct populations in an analyzed field of view. We present here the radial distribution of the 2G fraction in 29 GCs. The distributions show that all the GCs either have a flat distribution or more centrally concentrated 2G stars. Notably, we find that the fraction of 1G stars outside the half-light radius is clearly bifurcated across all mass range. It implies that a group of GCs with lower 1G fractions (hereafter Group II) have efficiently lost their 1G stars in the outermost cluster regions. In fact, in connection with the trends of the radial distribution, most GCs of Group II have spatially mixed populations, while only less massive GCs in Group I (a group with higher 1G fraction) show that feature. Lastly, we investigate links between these two groups and host cluster parameters. We find that most GCs of Group II are distributed along a broader range of galactocentric distances with smaller perigalactic distances < 3.5 kpc. Besides, by using the Gaia data, it is observed that Group II GCs have higher energy on the integrals of motion diagrams than Group I GCs.

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arXiv2024

Exploring Simple-Population and Multiple-Population Globular Clusters in the Outer Galactic Halo using the Hubble Space Telescope

The pseudo two-color diagram, known as chromosome map (ChM), is a valuable tool for identifying globular clusters (GCs) that consist of single or multiple stellar populations (MPs). Recent surveys of Galactic GCs using the ChM have provided stringent observational constraints on the formation of GCs and their stellar populations. However, these surveys have primarily focused on GCs at moderate distances from the Galactic center and composed of MPs. In this paper, we present the first detailed study of the stellar composition of four GCs in the outer halo of the Milky Way: Arp 2, Ruprecht 106, Terzan 7, and Terzan 8. Our analysis is based on high-precision photometry obtained from images collected with the Hubble Space Telescope in the F275W, F336W, F438W, F606W, and F814W bands. We find that Ruprecht 106 and Terzan 7 are composed solely of a single stellar population, whereas Arp 2 and Terzan 8 host both first- and second-population stars. In these clusters, the second population comprises about half and one-third of the total number of GC stars, respectively. The results from this paper and the literature suggest that the threshold in the initial GC mass, if present, should be smaller than approximately 10^5 M$_{\odot}$. The first-population stars of Arp 2 and Terzan 8, along with the stars of the simple-population GCs Ruprecht 106 and Terzan 7, exhibit intrinsic F275W - F814W color spreads, likely indicative of [Fe/H] variations of approximately 0.05 -- 0.30 dex. This suggests that star-to-star metallicity variations are a common feature of star clusters, regardless of the presence of MPs.

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arXiv2024

Spectro-Photometry and Radial Distribution of Multiple Stellar Populations in Globular Clusters from Gaia XP Spectra

Understanding the formation of multiple populations in globular clusters (GCs) represents a challenge for stellar population studies. Nevertheless, the outermost cluster regions, likely to hold clues about the initial configuration of GC stars, remain underexplored. We use synthetic spectra reflecting the chemical compositions of first- and second-population (1P, 2P) stars in 47Tucanae to identify spectral regions sensitive to these populations. This led us to define new photometric bands that effectively distinguish 1P and 2P giant stars using Gaia XP spectra. Testing these filters, we constructed the pseudo two-color diagrams dubbed chromosome maps (ChMs) and, for the first time, identified 1P and 2P stars in the cluster's outermost regions and beyond its tidal radius. We constructed similar diagrams for NGC3201, NGC6121, NGC6752, and NGC6397, thus exploring GCs with different metallicities. The ChMs effectively distinguished multiple populations in the outer regions of all clusters, except for the metal-poor NGC6397. Our findings, together with literature results from more-internal regions, show that the 2P stars of 47Tucanae are more-centrally concentrated than the 1P. A similar pattern is seen for 2P stars with extreme chemical composition of NGC3201. The multiple populations of NGC6121, and NGC6752 share the same radial distributions. These radial behaviors are consistent with the GC formation scenarios where 2P stars originate in the central regions. Noticeably, results on NGC3201 are in tension with the conclusion from recent work that its 1P is more centrally concentrated than the 2P and might form with more central concentration.

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arXiv2024

Hubble Space Telescope survey of Magellanic Cloud star clusters. Binaries among the split main sequences of NGC 1818, NGC 1850, and NGC 2164

Nearly all star clusters younger than ~600 Myr exhibit extended main sequence turn offs and split main sequences (MSs) in their color-magnitude diagrams. Works based on both photometry and spectroscopy have firmly demonstrated that the red MS is composed of fast-rotating stars, whereas blue MS stars are slow rotators. Nevertheless, the mechanism responsible for the formation of stellar populations with varying rotation rates remains a topic of debate. Potential mechanisms proposed for the split MS include binary interactions, early evolution of pre-main sequence stars, and the merging of binary systems, but a general consensus has yet to be reached. These formation scenarios predict different fractions of binaries among blue- and red-MS stars. Therefore, studying the binary populations can provide valuable constraints that may help clarify the origins of the split MSs. We use high-precision photometry from the Hubble Space Telescope (HST) to study the binaries of three young Magellanic star clusters exhibiting split MS, namely NGC 1818, NGC 1850, and NGC 2164. By analyzing the photometry in the F225W, F275W, F336W, and F814W filters for observed binaries and comparing it to a large sample of simulated binaries, we determine the fractions of binaries within the red and the blue MS. We find that the fractions of binaries among the blue MS are higher than those of red-MS stars by a factor of ~1.5, 4.6, and ~1.9 for NGC 1818, NGC 1850, and NGC 2164, respectively. We discuss these results in the context of the formation scenarios of the split MS.

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arXiv2024

A JWST project on 47 Tucanae. NIRSpec spectroscopy of multiple populations among M dwarfs

We present the first spectroscopic estimates of the chemical abundance of M dwarf stars in a globular cluster (GC), namely 47 Tucanae. By exploiting NIRSpec on board the James Webb Space Telescope (JWST) we gathered low-resolution spectra for 28 stars with masses in the range ~0.4-0.5 solar masses. The spectra are strongly affected by the H2O water vapour bands which can be used as indicators of the oxygen abundance. The spectral analysis reveals that the target stars feature a different O abundance, with a difference of ~0.40 dex between first and the most-polluted second population. The observed range is similar to that observed among red giant stars. This result reinforces previous findings based on the analysis of photometric diagrams, including the ``chromosome maps'', providing a first, and more direct, evidence of light element variations in the M dwarfs' mass regime. The observation that the multiple populations, with their variations in light elements, exhibit the same patterns from the lower main sequence all the way to the red giant branch further strengthens the notion that multiple stellar populations in globular clusters formed in a series of bursts of star formation.

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arXiv2024

On the original composition of the gas forming first-generation stars in clusters: insights from HST and JWST

Globular cluster (GC) stars composed of pristine material (first-generation, 1G, stars) are not chemically homogeneous, as they exhibit extended sequences in the "Chromosome Map" (ChM). Recent studies characterized 1G stars within the center of 55 Galactic GCs, revealing metallicity variations. Despite this progress, several unanswered questions persist, particularly concerning the link between the 1G metallicity spread and factors such as the radial distance from the cluster center or the host GC parameters. Additionally, it remains unclear whether the extended 1G sequence phenomenon is exclusive to old Galactic GCs with multiple populations. This work addresses these open issues, examining 1G stars in different environments. First, we combine Hubble Space Telescope (HST) and James Webb Space Telescope photometry of the GC 47 Tucanae to study 1G stars at increasing distances from the cluster center. We find that metal-rich 1G stars are more centrally concentrated than metal-poor ones, suggesting a metallicity radial gradient. Additionally, the two groups of 1G stars share similar kinematics. Since our analysis focuses on giant stars in the cluster center and M dwarfs in external fields, we discuss the possibility that the metallicity distribution depends on stellar mass. Subsequently, we analyze HST multi-band photometry of two simple-population clusters, NGC 6791 and NGC 1783, revealing elongated sequences in the ChM associated with metallicity variations. Finally, we investigate the 1G color distribution in 51 GCs, finding no connections with the host cluster parameters. These results shed light on the complex nature of 1G stars, providing insights into the GC formation environment.

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arXiv2024

A JWST project on 47 Tucanae. Overview, photometry and early spectroscopic results of M dwarfs, and observation of brown dwarfs

The James Webb Space Telescope (JWST) observations have been demonstrated to be efficient in detecting globular clusters' (GCs) multiple stellar populations in the low mass regime of M dwarfs. We present an overview, and first results, of different projects that can be explored by using the JWST observations gathered under the GO2560 for 47 Tucanae, a first program entirely devoted to the investigation of multiple populations in very low mass stars, which includes spectroscopic data for the faintest GC stars for which spectra are available. Our color-magnitude diagram (CMD) shows some substructures for ultracool stars, including gaps and breaks in slope. In particular, we observe both a gap and a minimum in the F322W2 luminosity function less than one magnitude apart, and discuss which one could be associated with the H-burning limit. We detect stars fainter than this minimum, very likely the brown dwarfs. We corroborate the ubiquity of the multiple populations across different masses, from ~0.1 solar masses up to red giants (~0.8 solar masses). The oxygen range inferred from the M dwarfs, both from the CMD and from the spectra of two M dwarfs associated with different populations, is similar to that observed in giants. We have not detected any difference between the fractions of stars in distinct populations across stellar masses >~0.1 solar masses. This work demonstrates the JWST's capability in uncovering multiple populations within M dwarfs and illustrates the possibility to analyse very low-mass stars in GCs approaching the H-burning limit and the brown-dwarf sequence.

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arXiv2023

GN-z11: witnessing the formation of second generation stars and an accreting massive black hole in a massive star cluster

We explore the possibility that the N-rich young proto-galaxy GN-z11 recently observed at z=10.6 by the James Webb Space Telescope is the result of the formation of second generation stars from pristine gas and Asymptotic Giant Branch (AGB) ejecta in a massive globular cluster or nuclear star cluster. We show that a second generation forming out of gas polluted by the ejecta of massive AGB stars and mixed with gas having a standard composition accounts for the unusually large N/O in the GN-z11 spectrum. The timing of the evolution of massive (4-7.5M$_{\odot}$) AGBs also provides a favourable environment for the growth of a central stellar mass black hole to the Active Galactic Nucleus stage observed in GN-z11. According to our model the progenitor system was born at an age of the Universe of $\simeq 260 - 380$Myr, well within the pre-reionization epoch.

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arXiv2023

The metallicity variations along the chromosome maps: The Globular Cluster 47 Tucanae

The "chromosome maps" (ChMs) of globular clusters (GCs) have revealed that these ancient structures are not homogeneous in metallicity in various ways, and in different natures. The Type II GCs generally display larger variations, sometimes coupled with slow neutron capture (s) element enrichment on the ChMs redder sequences, which has been interpreted as due to multiple generations of stars. On the other hand, most GCs have inhomogeneous first populations (1P) in the form of large ranges in the Delta(F275W,F814W) values, pointing towards a not fully mixed pristine molecular cloud. We analyse the chemical composition the GC 47 Tucanae, which shows both inhomogeneous 1P stars and, although not formally a Type II GC, hosts a small number of stars distributed on a red side of the main stream of ChM stars. Our results suggest that 1P stars are not homogeneous in the overall metallicity, with variations of the order of ~0.10 dex in all the chemical species. The anomalous stars distributed on a redder sequence of the ChM, are further enriched in metals, but without any evidence for a significant enrichment in the s elements. Our three second population stars located on the normal component of the map, have metallicities similar to those of the metal-richer 1P group, suggesting that this population formed from these stars. Although three stars is a too-small sample to draw strong conclusions, the low spread in metals of these objects might point towards a formation in a fully mixed medium, possibly after a cooling flow phase.

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arXiv2023

A deep dive into the Type II Globular Cluster NGC 1851

About one-fifth of the Galactic globular clusters (GCs), dubbed Type II GCs, host distinct stellar populations with different heavy elements abundances. NGC 1851 is one of the most studied Type II GCs, surrounded by several controversies regarding the spatial distribution of its populations and the presence of star-to-star [Fe/H], C+N+O, and age differences. This paper provides a detailed characterization of its stellar populations through Hubble Space Telescope (HST), ground-based, and Gaia photometry. We identified two distinct populations with different abundances of s-process elements along the red-giant branch (RGB) and the sub-giant branch (SGB) and detected two sub-populations among both s-poor (canonical) and s-rich (anomalous) stars. To constrain the chemical composition of these stellar populations, we compared observed and simulated colors of stars with different abundances of He, C, N, and O. It results that the anomalous population has a higher CNO overall abundance compared to the canonical population and that both host stars with different light-element abundances. No significant differences in radial segregation between canonical and anomalous stars are detected, while we find that among their sub-populations, the two most chemical extremes are more centrally concentrated. Anomalous and canonical stars show different 2D spatial distributions outside ~3 arcmin, with the latter developing an elliptical shape and a stellar overdensity in the northeast direction. We confirm the presence of a stellar halo up to ~80 arcmin with Gaia photometry, tagging 14 and five of its stars as canonical and anomalous, respectively, finding a lack of the latter in the south/southeast field.

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arXiv2023

Hubble Space Telescope survey of Magellanic Cloud star clusters. UV-dim stars in young clusters

Young and intermediate-age star clusters of both Magellanic Clouds exhibit complex color-magnitude diagrams. In addition to the extended main-sequence turn-offs (eMSTOs), commonly observed in star clusters younger than ~2 Gyr, the clusters younger than ~800 Myr exhibit split main sequences (MSs). These comprise a blue MS, composed of stars with low-rotation rates, and a red MS, which hosts fast-rotating stars. While it is widely accepted that stellar populations with different rotation rates are responsible for the eMSTOs and split MSs, their formation and evolution are still debated. A recent investigation of the ~1.7 Gyr old cluster NGC1783 detected a group of eMSTO stars extremely dim in UV bands. Here, we use multi-band Hubble Space Telescope photometry to investigate five star clusters younger than ~200 Myr, including NGC1805, NGC1818, NGC1850, and NGC2164 in the Large Magellanic Cloud, and the Small-Magellanic Cloud cluster NGC330. We discover a group of bright MS stars in each cluster that are significantly dim in the F225W and F275W bands, similar to what is observed in NGC1783. Our result suggests that UV-dim stars are common in young clusters. The evidence that most of them populate the blue MS indicates that they are slow rotators. As a byproduct, we show that the star clusters NGC1850 and BHRT5b exhibit different proper motions, thus corroborating the evidence that they are not gravitationally bound.

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arXiv2023

Multiple Stellar Populations in Globular Clusters with JWST: a NIRCam view of 47 Tucanae

We use images collected with the near-infrared camera (NIRCam) on board the James Webb Space Telescope and with the Hubble Space Telescope (HST) to investigate multiple populations at the bottom of the main sequence (MS) of 47 Tucanae. The F115W vs. F115W-F322W2 CMD from NIRCam shows that, below the knee, the MS stars span a wide color range, where the majority of M-dwarfs exhibit blue colors, and a tail of stars are distributed toward the red. A similar pattern is observed from the F160W vs. F110W-F160W CMD from HST, and multiple populations of M-dwarfs are also visible in the optical F606W vs. F606W-F814W CMD. The NIRCam CMD shows a narrow sequence of faint MS stars with masses smaller than 0.1 solar masses. We introduce a chromosome map of M-dwarfs that reveals an extended first population and three main groups of second-population stars. By combining isochrones and synthetic spectra with appropriate chemical composition, we simulate colors and magnitudes of different stellar populations in the NIRCam filters (at metallicities [Fe/H]=-1.5 and [Fe/H]=-0.75) and identify the photometric bands that provide the most efficient diagrams to investigate the multiple populations in globular clusters. Models are compared with the observed CMDs of 47 Tucanae to constrain M-dwarfs' chemical composition. Our analysis suggests that the oxygen range needed to reproduce the colors of first- and second-population M-dwarfs is similar to that inferred from spectroscopy of red giants, constraining the proposal that the chemical variations are due to mass transfer phenomena in proto-clusters.

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arXiv2023

Differential reddening in the direction of 56 Galactic globular clusters

The presence of differential reddening in the direction of Galactic globular clusters (GCs) has proven to be a serious limitation in the traditional colour-magnitude diagram (CMD) analysis. Here, we estimate local reddening variations in the direction of 56 Galactic GCs. To do that, we use the public catalogs derived as part of the Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters, which include photometry in the F275W, F336W, F438W, F606W, and F814W filters. We correct photometry for differential reddening finding that for 21 out of 56 GCs the adopted correction procedure significantly improves the CMDs. Moreover, we measure the reddening law in the direction of these clusters finding that $R_{V}$ exhibits a high level of variability within the Galaxy, ranging from $\sim2.0$ to $\sim4.0$. The updated values of $R_{V}$ have been used to improve the determination of local reddening variations and derive high-resolution reddening maps in the direction of the 21 highly-reddened targets within our sample. To compare the results of the different clusters, we compute the 68$^{\rm th}$ percentile of the differential-reddening distribution, $σ_{ΔA_{\rm F814W}}$. This quantity ranges from 0.003 mag to 0.030 mag and exhibits a significant anti-correlation with the absolute module of the Galactic latitude and a strong correlation with the average reddening in the direction of each cluster. Therefore, highly-reddened GCs located in the proximity of the Galactic plane typically show higher differential-reddening variations across their field of view.

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arXiv2023

On the role of dust and mass loss in the extended main sequence turnoff of star clusters: the case of NGC 1783

The Color Magnitude Diagram (CMD) morphology of the "extended" main sequence turnoff (eMSTO) and upper main sequence (MS) of the intermediate age ($\lesssim 2$ Gyr) Large Magellanic Cloud Cluster NGC 1783 shows the presence of a small group of UV-dim stars, that, in the ultraviolet Hubble Space Telescope filters, are located at colors on the red side of the typical "fan" shape displayed by the eMSTO. We model the UV-dim stars by assuming that some of the stars which would intrinsically be located on the left side of the eMSTO are obscured by a ring of dust due to grain condensation at the periphery of the excretion disc expelled when they spin at the high rotation rates typical of stars in the Be stage. A reasonably low optical depth at 10$μ$ is necessary to model the UV-dim group. Introduction of dust in the interpretation of the eMSTO may require a substantial re-evaluation of previous conclusions concerning the role of age and/or rotation spreads in the MC clusters: the entire eMSTO can be populated by dusty stars, and the reddest UV-dim stars simply represents the tail of the distribution with both maximum obscuration and the dust ring seen along the line of sight. The model stars having higher rotational projected velocity ($v \sin$ i) are predicted to be preferentially redder than the slowly-rotating stars. The mass loss responsible for the dust may also cause the non-monotonic distribution of stars in the upper main sequence, with two peaks and gaps showing up in the UV CMD.

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arXiv2022

Hubble Space Telescope survey of Magellanic Cloud star clusters. Photometry and astrometry of 113 clusters and early results

In the past years, we have undertaken an extensive investigation of LMC and SMC star clusters based on HST data. We present photometry and astrometry of stars in 101 fields observed with the WFC/ACS, UVIS/WFC3 and NIR/WFC3 cameras. These fields comprise 113 star clusters. We provide differential-reddening maps and illustrate various scientific outcomes that arise from the early inspection of the photometric catalogs. In particular, we provide new insights on the extended main-sequence turn-off (eMSTO) phenomenon: i) We detected eMSTOs in two clusters, KMHK361 and NGC265, which had no previous evidence of multiple populations. This finding corroborates the conclusion that the eMSTO is a widespread phenomenon among clusters younger than ~2 Gyr. ii) The homogeneous color-magnitude diagrams (CMDs) of 19 LMC clusters reveal that the distribution of stars along the eMSTO depends on cluster age. iii) We discovered a new feature along the eMSTO of NGC1783, which consists of a distinct group of stars going on the red side of the eMSTO in CMDs composed of ultraviolet filters. Furthermore, we derived the proper motions of stars in the fields of view of clusters with multi-epoch images. Proper motions allowed us to separate the bulk of bright field stars from cluster members and investigate the internal kinematics of stellar populations in various LMC and SMC fields. As an example, we analyze the field around NGC346 to disentangle the motions of its stellar populations, including NGC364 and BS90, young and pre-MS stars in the star-forming region associated with NGC346, and young and old field stellar populations of the SMC. Based on these results and the fields around five additional clusters, we find that young SMC stars exhibit elongated proper-motion distributions that point toward the LMC, thus bringing new evidence for a kinematic connection between the LMC and SMC.

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