arXiv subjects

Igor V. Chilingarian

Publications and source records attributed to Igor V. Chilingarian.

At least 19 recordsLinked to original sources

arXiv2026

Ram-pressure-induced star formation in low-mass galaxies infalling on-to the Coma cluster: insights from DESI

Ram-pressure stripping is a key driver of galaxy morphological transformation in clusters, contributing to the formation of quenched, especially dwarf, populations. Ram-pressure compression can also induce a starburst prior to quenching and build up significant stellar mass in an initially gas-rich galaxy. The detailed physics of these processes remains poorly understood, especially in the low-mass regime. Here we demonstrate that the key factor for a ram-pressure induced starburst in a low-mass galaxy is its angular momentum within a host cluster. In this study, we select a sample of 41 post-starburst galaxies (PSGs) in the Coma cluster using the DESI EDR spectroscopic data, extending to low luminosities ($M_g < -14$). This sample is at least 90% complete down to $M_g \approx -14.8$, which enabled us a systematic analysis of their properties. For each galaxy, we use projected cluster-centric distances and line-of-sight velocities to constrain the normalized orbital angular momentum and a 3D radial coordinate to the cluster center, assuming zero orbital energy. The resulting probability distributions show that while star-forming galaxies are split into two populations favoring intermediate and high angular momentum, almost all PSGs prefer high angular momentum. Our analysis statistically demonstrates that ram-pressure-induced starbursts are more efficient on tangential orbits, where gas stripping proceeds slowly enough to allow substantial star formation before gas removal.

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arXiv2026

HI Observations of Giant Low Surface Brightness Galaxies

Giant low surface brightness galaxies (gLSBs) are galaxies with extremely extended, faint, optical disks over 50 kpc in radius and have high total masses which can reach 10^12 solar masses. The existence of such galaxies is problematic for current models of galaxy formation, since the major mergers responsible for the large total mass would likely have destroyed the extended optical disk. Examining the gas content of these galaxies is an important step in determining their formation mechanism, whether it be through slow gas accretion or the large disk (re)forming after a major merger. We present neutral atomic hydrogen (HI) observations of 19 gLSBs identified with the Hyper Suprime-Cam Subaru Strategic Program survey. Although most have high HI masses, they are generally lower than expected based on their large optical sizes, and we do identify some gLSBs with unusually low gas content. The HI spectra of these galaxies show evidence for a rotational disk, though these disks are more asymmetric than other galaxies with comparable mass. Four galaxies with similar surface brightness profiles to the gLSBs have also been selected from the Numerical Investigation of a Hundred Astrophysical Objects (NIHAO) simulation for comparison. There is evidence for significant galaxy mergers in the past for three of these NIHAO galaxies and these three galaxies show similar asymmetry in their HI spectra. Together, these results could indicate the large optical disk of gLSBs are the result of a recent merger.

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arXiv2026

MUSE Study of Two Giant Low-surface-brightness Galaxies with Compact Satellites

Giant low-surface-brightness disk galaxies (gLSBGs) are rare objects with disk radii up-to 160 kpc and dynamical masses of an order of up to 10$^{12}$ $M_{\odot}$. Their very existence challenges currently accepted theories of galaxy formation and evolution, as it is difficult to build such large, dynamically cold disks through mergers without destroying them. We present deep MUSE mosaic observations of two nearby gLSBGs with compact elliptical satellites: UGC 1382, which hosts a globally counter-rotating gaseous disk, and AGC 192040, which does not. We analyze properties of ionized gas and present spatially resolved kinematics and metallicity maps; as well as stellar population analysis for the central regions of the galaxies. The radial gradients of gas-phase metallicities are flat for both galaxies. Our estimates of the effective oxygen yield suggest 'passive' gas in the outskirts of both stellar systems that is not involved in star formation. Our observational data indicate that both galaxies experienced mergers several Gyrs ago. However, the scenarios of formation of giant disks appear to be slightly different for these two systems. For AGC 192040 we propose the gas accretion from the filament followed by the intermediate-mass ratio merger with the companion on a prograde orbit. For UGC 1382 multiple gas-rich mergers with companions on retrograde orbits are preferred by the data.

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arXiv2025

Stellar CoRGI in MaNGA: Stellar Counterrotating Galaxies Identified in the MaNGA Survey

Stellar counterrotating (CR) galaxies are systems hosting two large-scale stellar components rotating in opposite directions -- a main, preexisting galaxy body with an older stellar population and a younger CR stellar disk likely formed from externally accreted gas. Such systems offer a unique opportunity to study disk assembly by analyzing the stellar populations of each component. Using integral field spectroscopic data from the SDSS-IV Mapping Nearby Galaxies at Apache Point Observatory survey, we identified a sample of 120 CR disk galaxies (65 reliable and 55 probable systems) by inspecting their kinematic maps and analyzing the shape of the stellar line-of-sight velocity distribution, which was recovered nonparametrically. Of these, 74 CR galaxies have not been reported in previous studies. For one-third of our sample, we further derived the ages and metallicities of stars for both disks via a spectral decomposition technique. We show that the observed spatial bimodality -- where the CR disk either is concentrated in the central region (inner counterrotation) or dominates the outer part of the galaxy (outer counterrotation) -- is driven by differences in the stellar mass and angular momentum of the CR disk. The wide range of stellar metallicities observed in CR disks suggests that no single source of external material is solely responsible for the formation of counterrotation in all galaxies; instead, proposed mechanisms such as merger with gas-rich satellites, accretion from cosmic filaments, and exchange of gas between neighboring galaxies can dominate in individual cases.

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arXiv2025

Optical Emission-Line Properties of eROSITA-selected SDSS-V Galaxies

We present and discuss optical emission line properties obtained from the analysis of Sloan Digital Sky Survey (SDSS) spectra for an X-ray selected sample of 3684 galaxies (0.002 < z < 0.55), drawn from the eRASS1 catalog. We modeled SDSS-V DR19 spectra using the NBursts full spectrum fitting technique with E-MILES simple stellar populations (SSP) models and emission line templates to decompose broad and narrow emission line components for correlation with X-ray properties. We place the galaxies on the Baldwin-Phillips-Terlevich (BPT) diagram to diagnose their dominant excitation mechanism. We show that the consistent use of the narrow component fluxes shifts most galaxies systematically and significantly upward to the active galactic nuclei (AGN) region on the BPT diagram. On this basis, we confirm the dependence between a galaxys position on the BPT diagram and its (0.2-2.3 keV) X-ray/H$α$ flux ratio. We also verified the correlation between X-ray luminosity and emission line luminosities of the narrow [O\iii]$λ5007$ and broad H$α$ component; as well as the relations between the Supermassive Black Hole (SMBH) mass, the X-ray luminosity, and the velocity dispersion of the stellar component ($σ_{*}$) on the base on the unique sample of optical spectroscopic follow-up of X-ray sources detected by eROSITA. These results highlight the importance of emission line decomposition in AGN classification and refine the connection between X-ray emission and optical emission line properties in galaxies.

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arXiv2025

A transiting giant planet in orbit around a 0.2-solar-mass host star

Planet formation models suggest that the formation of giant planets is significantly harder around low-mass stars, due to the scaling of protoplanetary disc masses with stellar mass. The discovery of giant planets orbiting such low-mass stars thus imposes strong constraints on giant planet formation processes. Here, we report the discovery of a transiting giant planet orbiting a $0.207 \pm 0.011 M_{\odot}$ star. The planet, TOI-6894 b, has a mass and radius of $M_P = 0.168 \pm 0.022 M_J (53.4 \pm 7.1 M_{\oplus})$ and $R_P = 0.855 \pm 0.022 R_J$, and likely includes $12 \pm 2 M_{\oplus}$ of metals. The discovery of TOI-6894 b highlights the need for a better understanding of giant planet formation mechanisms and the protoplanetary disc environments in which they occur. The extremely deep transits (17% depth) make TOI-6894 b one of the most accessible exoplanetary giants for atmospheric characterisation observations, which will be key for fully interpreting the formation history of this remarkable system and for the study of atmospheric methane chemistry.

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arXiv2025

A Census of Compact Elliptical Galaxies in the Coma Cluster

Compact elliptical (cE) galaxies are compact stellar systems with stellar masses of $10^8 \leq M_*/M_\odot \leq 10^{10}$ and radii typically < 0.6 kpc. Here we investigate the properties of 13 cE galaxies in the Coma cluster, six newly identified. Our goal in this paper is to explore whether these cEs form directly in the cluster environment or are pre-processed in small groups before infalling. We find that pre-processing in groups significantly contributes to the cE population in the Coma cluster. We analyze Hyper Suprime-Cam (HSC) g band Coma images and validate our photometric measurements through comparison with Hubble Space Telescope (HST) data. We also analyze spectroscopic data from the Dark Energy Spectroscopic Instrument (DESI). We significantly expand the known cE population in the Coma cluster through joint photometric and spectroscopic selection. We identify a subpopulation of cEs that likely formed in infalling groups, through their association with host galaxies, their positions on the caustic diagram, and their projected phase-space trajectories. We estimate that the central cE population will increase by 30% within the next 0.4 Gyr, highlighting the important role of pre-processing in cE evolution.

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arXiv2025

Supermassive black hole mass measurement in the spiral galaxy NGC 4736 Using JWST/NIRSpec stellar kinematics

We present accurate mass measurements of the central supermassive black hole (SMBH) in NGC 4736 (M 94).\ We used the ``gold-standard" stellar absorption features (CO band heads) at $\sim$2.3 ${\rm μm}$, as opposed to gas emission lines, to trace the dynamics in the nuclear region, easily resolving the SMBH's sphere of influence. The analysis uses observations made with the integral field unit of the Near-Infrared Spectrograph (NIRSpec) on the {\it James Webb} Space Telescope and a surface brightness profile derived from {\it Hubble} Space Telescope archival images. We used Jeans anisotropic models within a Bayesian framework, and comprehensive Markov chain Monte Carlo optimization, to determine the best-fit black hole mass, orbital anisotropy, mass-to-light ratio, and nucleus kinematical inclination. We obtained a SMBH mass $M_{\rm BH}=(1.60\pm0.16)\times10^7$ M$_\odot$ (1$σ$ random error), which is consistent with the $M_{\rm BH}$-$σ$ and $M_{\rm BH}$-$M_\star$ relations. This is the first dynamical measurement of a $M_{\rm BH}$ in NGC 4736 based on the stellar kinematics observed with NIRSpec. We thus settle a longstanding inconsistency between estimates based on nuclear emission-line tracers and the $M_{\rm BH}$-$σ$ relation. Our analysis shows that NIRSpec can detect SMBHs with $M_{\rm BH,min}\approx 5\times10^6$ M$_\odot$ in galaxies within 5 Mpc and $σ\approx100$ km s$^{-1}$

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arXiv2025

Dot to dot: high-$z$ little red dots in $M_{\rm bh}$-$M_{\rm \star}$ diagrams with galaxy-morphology-specific scaling relations

The high redshift 'little red dots' (LRDs) detected with the James Webb Space Telescope are considered to be the cores of emerging galaxies that host active galactic nuclei (AGN). For the first time, we compare LRDs with local compact stellar systems and an array of galaxy-morphology-dependent stellar mass-black hole mass scaling relations in the $M_{\rm bh}$-$M_{\star}$ diagrams. When considering the 2023-2024 masses for LRDs, they are not equivalent to nuclear star clusters (NSCs), with the latter having higher $M_{\rm bh}/M_{\star}$ ratios. However, the least massive LRDs exhibit similar $M_{\rm bh}$ and $M_{\rm \star,gal}$ values as ultracompact dwarf (UCD) galaxies, believed to be the cores of stripped/threshed galaxies. We show that the LRDs span the $M_{\rm bh}$-$M_{\rm \star,gal}$ diagram from UCD galaxies to primaeval lenticular galaxies. In contrast, local spiral galaxies and the subset of major-merger-built early-type galaxies define $M_{\rm bh}$-$M_{\star,gal}$ relations that are offset to higher stellar masses. Based on the emerging 2025 masses for LRDs, they may yet have similarities with NSCs, UCD galaxies, and green peas. Irrespective of this developing situation, we additionally observe that low-redshift galaxies with AGN align with the quasi-quadratic or steeper black hole scaling relations defined by local disc galaxies with directly measured black hole masses. This highlights the benefits of considering a galaxy's morphology - which reflects its accretion and merger history - to understand the coevolution of galaxies and their black holes. Future studies of spatially-resolved galaxies with secure masses at intermediate-to-high redshift hold the promise of detecting the emergence and evolution of the galaxy-morphology-dependent $M_{\rm bh}$-$M_{\star}$ relations.

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arXiv2025

Multi-wavelength study of a hyperluminous X-ray source near NGC 6099: a strong IMBH candidate

We report on the intriguing properties of a variable X-ray source projected at the outskirts of the elliptical galaxy NGC 6099 ($d \approx 139$ Mpc). If truly located near NGC 6099, this is a hyperluminous X-ray source that reached an X-ray luminosity $L_{X} \approx $ a few times $10^{42}$ erg s$^{-1}$ in 2012 February (XMM-Newton data), about 50 to 100 times brighter than in 2009 May (Chandra) and 2023 August (XMM-Newton). The X-ray spectrum was soft at all three epochs, with a thermal component at $kT \approx 0.2$ keV and a power-law photon index $>3$. Such properties make it a strong candidate for an intermediate mass black hole (IMBH). We also discovered a point-like, blue optical counterpart ($m_{g,{Vega}}\approx24.7$~mag, $M_{g,{Vega}}\approx-11.2$~mag), from images taken by the Canada-France-Hawaii Telescope, and later confirmed with Hubble Space Telescope observations. The optical continuum can be modeled as stellar emission from a compact star cluster or an X-ray-irradiated accretion disk, consistent with the IMBH scenario. We discuss alternative explanations for the nature of this system. A possible scenario is tidal stripping of an orbiting star, with repeated X-ray outbursts every few years. An alternative possibility is that the thermal X-ray emission seen in 2009 was from shocked gas in the self-intersecting tidal stream during the rising phase of a tidal disruption event, while the 2012 and 2023 emissions were from the fully-formed accretion disk.

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arXiv2025

NGC 3259: A Signal for an Untapped Population of Slowly Accreting Intermediate-Mass Black Holes

Low-mass active galactic nuclei (AGNs) can provide important constraints on the formation and evolution of supermassive black holes (SMBHs), a central challenge in modern cosmology. To date only small samples of intermediate-mass black holes (IMBHs, $M_{BH}<10^5M_{\odot}$) and 'lesser' supermassive black holes (LSMBHs, $M_{BH}<10^6M_{\odot}$) have been identified. Our present study of NGC 3259 at D=27 Mpc with the Binospec integral field unit spectrograph complemented with Keck Echelle Spectrograph and Imager observations demonstrates the need for and the power of the spectroscopic follow-up. NGC 3259 hosts a black hole with a mass of $M_{BH}=(1.7-4.1)\times10^5M_{\odot}$, inferred from multi-epoch spectroscopic data, that accretes at 1% of the Eddington limit as suggested by the analysis of archival XMM-Newton observations. It is the second nearest low-mass AGN after the archetypal galaxy NGC 4395. The spectroscopic data reveals a variable broad $Hα$ profile that is likely the result of asymmetrically distributed broad-line region (BLR) clouds or BLR outflow events. X-ray observations and the absence of an optical power-law continuum suggest partial obscuration of the accretion disk and hot corona by a dust torus. We estimate that the Sloan Digital Sky Survey could only detect similar objects to D=35 Mpc. A detailed photometric analysis of NGC 3259 using HST images provides a central spheroid stellar mass estimate 25 times lower than expected from the $M_{BH}-M^*_{sph}$ relation, making this galaxy a strong outlier. This discrepancy suggests divergent growth pathways for the central black hole and spheroid, potentially influenced by the presence of a bar in the galaxy. Finally, we demonstrate that the DESI and 4MOST surveys will detect low-accretion rate IMBHs and LSMBHs and the sensitivity of future X-ray instruments (such as AXIS and Athena) will secure their classification.

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arXiv2024

Spectroscopic confirmation of the galaxy clusters CARLA J0950+2743 at z=2.363, and CARLA-Ser J0950+2743 at z=2.243

Galaxy clusters, being the largest gravitationally bound structures in the Universe, are a powerful tool to study mass assembly at different epochs. At z$>$2 they give an unique opportunity to put solid constraints not only on dark matter halo growth, but also on the mechanisms of galaxy quenching and morphological transformation when the Universe was younger than 3.3 Gyr. However, the currently available sample of confirmed $z>2$ clusters remains very limited. We present the spectroscopic confirmation of the galaxy cluster CARLA J0950+2743 at $z=2.363\pm0.005$ and a new serendipitously discovered cluster, CARLA-Ser J0950+2743 at $z=2.243\pm0.008$ in the same region. We confirm eight star-forming galaxies in the first cluster, and five in the second by detecting [OII], [OIII] and $Hα$ emission lines. The analysis of a serendipitous X-ray observation of this field from Chandra reveals a counterpart with a total luminosity of $L_{0.5-5 keV} = 2.9\pm0.6\times10^{45}$ erg s$^{-1}$. Given the limited depth of the X-ray observations, we cannot distinguish the 1-D profile of the source from a PSF model, however, our statistical analysis of the 2-D profile favors an extended component that could be associated to a thermal contribution from the intra-cluster medium (ICM). If the extended X-ray emission is due to the hot ICM, the total dark matter mass for the two clusters would be $M_{200}=3.30 ^{+0.23}_{-0.26 (\mathrm{stat})}$ $^{+1.28}_{-0.96 (\mathrm{sys})} \times10^{14} M_{\odot}$. This makes our two clusters interesting targets for studies of the structure growth in the cosmological context. However, future investigations would require deeper high-resolution X-ray and spectroscopic observations.

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arXiv2024

A closer look at the extended edge-on low-surface brightness galaxies

To understand the origin of extended disks of low-surface brightness (LSB) galaxies, we studied in detail 4 such systems with large disks seen edge-on. Two of them are edge-on giant LSB galaxies (gLSBGs) recently identified by our team. The edge-on orientation of these systems boosts their surface brightnesses that provided an opportunity to characterize stellar populations spectroscopically and yielded the first such measurements for edge-on gLSBGs. We collected deep images of one galaxy using the 1.4-m Milanković Telescope which we combined with the archival Subaru Hyper Suprime-Cam and DESI Legacy Surveys data available for the three other systems, and measured the structural parameters of the disks. We acquired deep long-slit spectra with the Russian 6-meter telescope and the 10-m Keck II telescope and estimated stellar population properties in the high- and low-surface brightness regions as well as the gas-phase metallicity distribution. The gas metallicity gradients are shallow to flat in the range between 0 and -0.03 dex per exponential disk scale length, which is consistent with the extrapolation of the gradient -- scale length relation for smaller disk galaxies. Our estimates of stellar velocity dispersion in the LSB disks as well as the relative thickness of the disks indicate the dynamical overheating. Our observations favor mergers as the essential stage in the formation scenario for massive LSB galaxies.

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arXiv2023

Color Transformations of Photometric Measurements of Galaxies in Optical and Near-Infrared Wide-Field Imaging Surveys

Over the past 2 decades, wide-field photometric surveys in optical and infrared domains reached a nearly all-sky coverage thanks to numerous observational facilities operating in both hemispheres. However, subtle differences among exact realizations of Johnson and SDSS photometric systems require one to convert photometric measurements into the same system prior to analysis of composite datasets originating from multiple surveys. It turns out that the published photometric transformations lead to substantial biases when applied to integrated photometry of galaxies from the corresponding catalogs. Here we present photometric transformations based on piece-wise linear approximations of integrated photometry of galaxies in the optical surveys SDSS, DECaLS, BASS, MzLS, DES, DELVE, KiDS, VST ATLAS, and the near-infrared surveys UKIDSS, UHS, VHS, and VIKING. We validate our transformations by constructing k-corrected color-magnitude diagrams of non-active galaxies and measuring the position and tightness of the "red sequence". We also provide transformations for aperture magnitudes and show how they are affected by the image quality difference among the surveys. We present the implementation of the derived transformations in Python and IDL and also a web-based color transformation calculator for galaxies. By comparing DECaLS and DES, we identified systematic issues in DECaLS photometry for extended galaxies, which we attribute to the photometric software package used by DECaLS. As an application of our method, we compiled two multi-wavelength photometric catalogs for over 200,000 low- and intermediate-redshift galaxies originating from CfA FAST and Hectospec spectral archives.

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arXiv2023

KDG 64: a large dwarf spheroidal or a small ultradiffuse satellite of Messier 81

Low-mass early-type galaxies, including dwarf spheroidals (dSph) and brighter dwarf ellipticals (dE), dominate the galaxy population in groups and clusters. Recently, an additional early-type population of more extended ultradiffuse galaxies (UDGs) has been identified, sparking a discussion on the potential morphological and evolutionary connections between the three classifications. Here, we present the first measurements of spatially resolved stellar kinematics from deep integrated-light spectra of KDG 64 (UGC 5442), a large dSph galaxy in the M 81 group. From these data, we infer stellar population properties and dark matter halo parameters using Jeans dynamical modelling. We find an old, metal-poor stellar population with no young stars and a dark matter mass fraction of ~ 90 per cent within the half-light radius. These properties and the position of KDG 64 on the Fundamental Plane indicate that it is a local analogue of smaller UDGs in the Coma and Virgo clusters and is probably a transitional dSph-UDG object. Its evolutionary path cannot be uniquely established from the existing data, but we argue that supernovae feedback and tidal heating played key roles in shaping KDG 64.

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arXiv2023

The volume density of giant low surface brightness galaxies

Rare giant low surface brightness galaxies (gLSBGs) act as a stress test for the current galaxy formation paradigm. To answer the question `How rare are they?' we estimate their volume density in the local Universe. A visual inspection of 120~sq.~deg. covered by deep Subaru Hyper Suprime-Cam data was performed independently by four team members. We detected 42 giant disky systems (30 of them isolated) at $z\leq0.1$ with either $g$-band 27.7~mag~arcsec$^{-2}$ isophotal radius or four disc scalelengths $4h \geq 50$~kpc, 37 of which (including 25 isolated) had low central surface brightness ($μ_{0,g}\ge 22.7$ mag~arcsec$^{-2}$). This corresponds to volume densities of 4.70$\times 10^{-5}$ Mpc$^{-3}$ for all galaxies with giant extended discs and 4.04$\times 10^{-5}$ Mpc$^{-3}$ for gLSBGs, which converts to $\sim $12,700 such galaxies in the entire sky out to $z<0.1$. These estimates agree well with the result of the EAGLE cosmological hydrodynamical simulation. Giant disky galaxies represent the large-size end of the volume density distribution of normal-sized spirals, suggesting the non-exceptional nature of giant discs. We observe a high active galactic nucleus fraction among the newly found gLSBGs.

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arXiv2022

The origin of double-peak emission-line galaxies: rotating discs, bars or galaxy mergers?

Emission lines with a double-peak (DP) shape, detected in the centre of galaxies, have been extensively used in the past to identify peculiar kinematics such as dual active galactic nuclei, outflows or mergers. From a large DP galaxy sample, a connection to minor merger galaxies with ongoing star formation was suggested. To gain a better understanding of different mechanisms creating a DP signature, we here explore synthetic SDSS spectroscopic observations computed from disc models and simulations. We show how a DP signature is connected to the central part of the rotation curve of galaxies, which is mostly shaped by the stellar bulge. We, furthermore, find that bars can create strong DP emission-line signatures when viewed along their major axis. Major mergers can form a central rotating disc in late post-coalescence merger stages (1\,Gyr after the final coalescence), which creates a DP signature. Minor mergers tend to show a DP feature with no correlation to the galaxy inclination within 350\,Myr after the final coalescence. Comparisons of these scenarii with observations disfavour major mergers, since these show predominantly elliptical and only a few S0 morphologies. Furthermore, at such a late merger stage the enhanced star formation is most likely faded. Bars and minor mergers, on the other hand, can be compared quite well with the observations. Both observations coincide with increased star formation found in observations, and minor mergers in particular do not show any dependency with the observation direction. However, observations resolving the galaxy kinematics spatially are needed to distinguish between the discussed possibilities. More insight into the origin of DP will be gained by a broader comparison with cosmological simulations. The understanding of the DP origin can provide important tools to study the mass growth of galaxies in future high redshift surveys.

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arXiv2022

Detailed Chemical Abundances of Star Clusters in the Large Magellanic Cloud

We derive the first detailed chemical abundances of three star clusters in the Large Magellanic Cloud (LMC), NGC1831 (436+/-22 Myr), NGC1856 (350+/-18 Myr) and [SL63]268 (1230+/-62 Myr) using integrated-light spectroscopic observations obtained with the Magellan Echelle spectrograph on Magellan Baade telescope. We derive [Fe/H], [Mg/Fe], [Ti/Fe], [Ca/Fe], [Ni/Fe], [Mn/Fe], [Cr/Fe] and [Na/Fe] for the three clusters. Overall, our results match the LMC abundances obtained in the literature as well as those predicted by detailed chemical evolution models. For clusters NGC1831 and NGC1856, the [Mg/Fe] ratios appear to be slightly depleted compared to [Ca/Fe] and [Ti/Fe]. This could be hinting at the well-known Mg-Al abundance anti-correlation observed in several Milky Way globular clusters. We note, however, that higher signal-to-noise observations are needed to confirm such a scenario, particularly for NGC 1831. We also find a slightly enhanced integrated-light [Na/Fe] ratio for cluster [SL63]268 compared to those from the LMC field stars, possibly supporting a scenario of intracluster abundance variations. We stress that detailed abundance analysis of individual stars in these LMC clusters is required to confirm the presence or absence of MSPs.

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