arXiv subjects

Jacco Th. van Loon

Publications and source records attributed to Jacco Th. van Loon.

At least 37 records · Page 2Linked to original sources

arXiv2025

Metallicity Effects on Machine Learning Classification of Dusty Stellar Sources in the Magellanic Clouds

Differences in metallicity between the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) offer an opportunity to examine whether environmental metallicity affects the performance of machine learning models in classifying dusty stellar sources. The five stellar classes studied include young stellar objects (YSOs), red supergiants (RSGs), post-asymptotic giant branch stars (PAGBs), and oxygen- and carbon-rich asymptotic giant branch stars (OAGBs and CAGBs), which are key phases of stellar evolution involved in dust production. Using spectroscopically labeled data from the Surveying the Agents of Galaxy Evolution (SAGE) project, we trained and evaluated a probabilistic random forest (PRF) classifier with four approaches: (1) separate training on LMC and SMC, including all five classes, (2) excluding the underpopulated PAGB class, (3) combined LMC and SMC datasets, and (4) cross-galaxy training and testing. The model achieved 93\% accuracy on the SMC and 88\% on the LMC across all five classes. In the SMC, PAGB sources were misclassified as YSOs, mainly because of their small sample size (4 objects). When PAGB was excluded, both the LMC and the SMC reached 92\% accuracy. A combined dataset produced the same accuracy, and cross-galaxy training yielded similar results, indicating that metallicity does not significantly impact model performance. A comparison of absolute CMDs for the LMC and SMC confirms their similarity in stellar populations. These findings suggest that environmental metallicity has little effect on ML-based classification of dusty stellar sources, supporting the use of combined datasets and cross-galaxy models in low-metallicity environments.

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arXiv2025

Protostars at Subsolar Metallicity: First Detection of Large Solid-state Complex Organic Molecules in the Large Magellanic Cloud

We present the results of James Webb Space Telescope observations of the protostar ST6 in the Large Magellanic Cloud (LMC) with the Medium Resolution Spectrograph of the Mid-Infrared Instrument (4.9-27.9 $μ$m). Characterized by one-third to half-solar metallicity and strong UV radiation fields, the environment of the LMC allows us to study the physics and chemistry of star-forming regions under the conditions similar to those at earlier cosmological epochs. We detected five icy complex organic molecules (COMs): methanol (CH$_3$OH), acetaldehyde (CH$_3$CHO), ethanol (CH$_3$CH$_2$OH), methyl formate (HCOOCH$_3$), and acetic acid (CH$_3$COOH). This is the first conclusive detection of CH$_3$COOH ice in an astrophysical context, and CH$_3$CHO, CH$_3$CH$_2$OH, and HCOOCH$_3$ ices are the first secure detections outside the Galaxy and in a low-metallicity environment. We address the presence of glycolaldehyde (HOCH$_2$CHO, a precursor of biomolecules), an isomer of HCOOCH$_3$ and CH$_3$COOH, but its detection is inconclusive. ST6's spectrum is also rich in simple ices: H$_2$O, CO$_2$, CH$_4$, SO$_2$, H$_2$CO, HCOOH, OCN$^{-}$, HCOO$^{-}$, NH$_3$, and NH$_4^{+}$. We obtain the composition and molecular abundances in the icy dust mantles by fitting the spectrum in the 6.8-8.4 $μ$m range with a large sample of laboratory ice spectra using the ENIIGMA fitting tool or the local continuum method. We found differences in the simple and COM ice abundances with respect to H$_2$O ice between ST6 and Galactic protostars that likely reflect differences in metallicity and UV flux. More laboratory ice spectra of COMs are needed to better reconstruct the observed infrared spectra of protostars.

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arXiv2025

Study of HI Turbulence in the SMC Using Multi-point Structure Functions

Turbulence in the interstellar medium (ISM) plays an important role in many physical processes, including forming stars and shaping complex ISM structures. In this work, we investigate the HI turbulent properties of the Small Magellanic Cloud (SMC) to reveal what physical mechanisms drive the turbulence and at what scales. Using the high-resolution HI data of the Galactic ASKAP (GASKAP) survey and multi-point structure functions (SF), we perform a statistical analysis of HI turbulence in 34 subregions of the SMC. Two-point SFs tend to show a linear trend, and their slope values are relatively uniform across the SMC, suggesting that large-scale structures exist and are dominant in the two-point SFs. On the other hand, seven-point SF enables us to probe small-scale turbulence by removing large-scale fluctuations, which is difficult to achieve with the two-point SFs. In the seven-point SFs, we find break features at scales of 34-84 pc, with a median scale of $\sim$50 pc. This result indicates the presence of small-scale turbulent fluctuations in the SMC and quantifies its scale. In addition, we find strong correlations between slope values of the seven-point SFs and the stellar feedback-related quantities (e.g., H$α$ intensities, the number of young stellar objects, and the number of HI shells), suggesting that stellar feedback may affect the small-scale turbulent properties of the HI gas in the SMC. Lastly, estimated sonic Mach numbers across the SMC are subsonic, which is consistent with the fact that the HI gas of the SMC primarily consists of the warm neutral medium.

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arXiv2025

Multi-wavelength probes of the Milky Way's Cold Interstellar Medium: Radio HI and Optical KI Absorption with GASKAP and GALAH

We present a comparative analysis of interstellar hydrogen (HI) and potassium (KI) absorption from the radio and optical surveys, GASKAP and GALAH, to study the physical and kinematic properties of the cold interstellar medium (ISM) in the Milky Way foreground towards the Magellanic Clouds. By comparing GASKAP HI absorption with interstellar KI absorption detected in GALAH spectra of nearby stars (within 12 arcmin angular distance or a spatial separation of ~0.75 pc), we reveal a strong kinematic correlation between these two tracers of the cold neutral ISM. The velocity offsets between matched HI and KI absorption components are small, with a mean (median) offset of -1.3 (-1.2) km s-1 and a standard deviation of 2.3 km s-1. The high degree of kinematic consistency suggests a close spatial association between Ki and cold HI gas. Correlation analyses reveal a moderate positive relationship between HI and KI line-of-sight properties, such as KI column density with HI column density or HI brightness temperature. We observe a ~63% overlap in the detection of both species towards 290 (out of 462) GASKAP HI absorption lines of sight, and estimate a median KI/HI abundance ratio of ~2.3 x 10^(-10), in excellent agreement with previous findings. Our work opens up an exciting avenue of Galactic research that uses large-scale surveys in the radio and optical wavelengths to probe the neutral interstellar medium through its diverse tracers.

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arXiv2025

Comparison of Photometric and Spectroscopic Labels in Classifying Dusty Stellar Sources Using Machine Learning in the Magellanic Clouds

Dusty stellar sources, including young stellar objects (YSOs) and evolved stars such as oxygen- and carbon-rich AGBs (OAGBs, CAGBs), red supergiants (RSGs), and post-AGB stars (PAGBs), play a key role in the chemical enrichment of galaxies. Photometric surveys in the Magellanic Clouds have cataloged many such objects, but their classifications are often uncertain due to overlaps between populations. We trained machine learning models on spectroscopically labeled data from the SAGE project and applied them to photometric catalogs. The spectroscopic model achieves about 89\% accuracy. Applied to photometric labels, nearly all OAGBs are correctly identified, and YSOs have a 95\% confirmation rate. In contrast, 16\% of CAGBs are reclassified as OAGBs, only 8\% of RSGs retain their labels, and fewer than half of PAGBs are confirmed. Photometry is thus reliable for abundant populations with distinct signatures, but spectroscopic confirmation remains essential for rare or overlapping stellar classes.

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arXiv2025

New Interpretation for the Orientation of the LMC's Gaseous Arms B and E using ULLYSES

The Large Magellanic Cloud (LMC) experiences disruption from tidal and ram-pressure forces as it travels through the halo of the Milky Way. In this project, we combine radio emission-line observations from the GASS and GASKAP surveys with UV absorption-line observations from the HST Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) program to trace the material in front of the LMC. Along our 8 stellar sightlines near 30 Doradus, we observe gaseous structures likely associated with two arm-like features flowing in and around the LMC's disk. We detect the nearside gas in neutral, low, and medium ionization species. The lower-ionization species likely undergo both thermal and non-thermal broadening while the moderately-ionized phase is influenced by more non-thermal processes. The total integrated column density of AlIII decreases with increasing angular offset from 30 Doradus, with sightlines within 0.25 degrees containing more moderately ionized gas. We demonstrate from a Gaussian decomposition technique on the HI emission that both arms likely trace an additional 1.0 degree in Galactic longitude toward the 30 Doradus region than previously predicted. We constrain the orientation of the arms by suggesting that they likely converge around (l,b) =(280.5$^\circ$, -31.2$^\circ$) and at least partially cross in front of the LMC. Our observations are consistent with two competing origins of the arms: 1) outflowing material is swept back by tidal and ram-pressure forces or 2) tidally stripped inflows fuel the ongoing stellar activity inside the LMC. Future studies are needed to distinguish between these scenarios.

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arXiv2025

Red Supergiant Mass Loss and Mass-Loss Rates

This review discusses the causes, nature, importance and observational evidence of mass loss by red supergiants. It arrives at the perception that mass loss finds its origin in the gravity which makes the star a star in the first place, and is a mechanism for the star to equilibrate. This is corroborated by a careful examination of various popular historical and recent empirical mass-loss rate prescriptions and theoretical works, and which provides no evidence for an explicit dependence of red supergiant mass loss on metallicity though dust-associated mass loss becomes less prevalent at lower metallicity. It also identifies a common problem in methods that use tracers of mass loss, which do not correct for varying scaling factors (often because there is no information available on which to base such correction) and as a result tend to underestimate mass-loss rates at the lower end. Conversely, dense, extended chromospheres in themselves do not translate into high mass-loss rates, and the significance of stochastic mass loss can be overstated. On a population scale, on the other hand, binary interaction acts as a stochastic agent of mass loss of great import. In all, evidence is overwhelming that points at red supergiants at the lower mass end losing mass at insufficient rates to shed their mantles before core collapse, but massive (at birth) red supergiants to be prone to intense, dusty mass loss which sees them become hotter stars before meeting their fate. This is consistent with the identified progenitors of hydrogen-rich supernovae. Supernova evolution holds great promise to probe the mass loss but we caution against confusing atmospheres with winds. Finally, promising avenues are looked into, which could forge step-change progress in what has been a long and arduous search for the holy grail of red supergiant mass loss. We may yet find it!

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arXiv2025

Machine Learning Classification of Young Stellar Objects and Evolved Stars in the Magellanic Clouds Using the Probabilistic Random Forest Classifier

The Magellanic Clouds (MCs) are excellent locations to study stellar dust emission and its contribution to galaxy evolution. Through spectral and photometric classification, MCs can serve as a unique environment for studying stellar evolution and galaxies enriched by dusty stellar point sources. We applied machine learning classifiers to spectroscopically labeled data from the Surveying the Agents of Galaxy Evolution (SAGE) project, which involved 12 multiwavelength filters and 618 stellar objects at the MCs. We classified stars into five categories: young stellar objects (YSOs), carbon-rich asymptotic giant branch (CAGB) stars, oxygen-rich AGB (OAGB) stars, red supergiants (RSG), and post-AGB (PAGB) stars. Following this, we augmented the distribution of imbalanced classes using the Synthetic Minority Oversampling Technique (SMOTE). Therefore, the Probabilistic Random Forest (PRF) classifier achieved the highest overall accuracy, reaching ${89\%}$ based on the recall metric, in categorizing dusty stellar sources before and after data augmentation. In this study, SMOTE did not impact the classification accuracy for the CAGB, PAGB, and RSG categories but led to changes in the performance of the OAGB and YSO classes.

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arXiv2025

A neutral hydrogen absorption study of cold gas in the outskirts of the Magellanic Clouds using the GASKAP-HI survey

Cold neutral hydrogen (HI) is a crucial precursor for molecular gas formation and can be studied via HI absorption. This study investigates HI absorption in low column density regions of the Small and Large Magellanic Clouds (SMC and LMC) using the Galactic-ASKAP HI (GASKAP-HI) survey, conducted by the Australian Square Kilometer Array Pathfinder (ASKAP). We select 10 SMC directions in the outer regions and 18 LMC directions, with 4 in the outskirts and 14 within the main disk. Using the radiative transfer method, we decompose the emission and absorption spectra into individual cold neutral medium (CNM) and warm neutral medium (WNM) components. In the SMC, we find HI peak optical depths of 0.09-1.16, spin temperatures of ~20-50 K, and CNM fractions of 1-11%. In the LMC, optical depths range from 0.03 to 3.55, spin temperatures from ~10 to 100 K, and CNM fractions from 1% to 100%. The SMC's low CNM fractions likely result from its low metallicity and large line-of-sight depth. Additionally, the SMC's outskirts show lower CNM fractions than the main body, potentially due to increased CNM evaporation influenced by the hot Magellanic Corona. Shell motions dominate the kinematics of the majority of CNM clouds in this study and likely supply cold HI to the Magellanic Stream. In the LMC, high CNM fraction clouds are found near supergiant shells, where thermal instability induced by stellar feedback promotes WNM-to-CNM transition. Although no carbon monoxide (CO) has been detected, enhanced dust shielding in these areas helps maintain the cold HI.

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arXiv2025

The Gaseous Blowout of the 30 Doradus Starburst Region in the LMC

Widespread galactic winds emanate from the Large Magellanic Cloud (LMC), with the 30 Doradus starburst region generating the fastest and most concentrated gas flows. We report on the gas distribution, kinematics, and ionization conditions of the near-side outflow along 8 down-the-barrel sightlines using UV absorption-line observations from the HST's ULLYSES program for this region along with H I 21-cm observations from the GASS and GASKAP surveys. We find that within 1.7 degrees from the center of 30 Doradus, the wind reaches maximum speeds of $100-150\,\text{km}\,\text{s}^{-1}$ from the LMC's disk. The total integrated column densities of low-ions (O I, Si II, and Fe II) in the blueshifted wind, up to $v_{\rm LSR}=150\,\text{km}\,\text{s}^{-1}$, are highest near the center and decline radially outward. We estimate an outflow mass of $M_{\rm outflow,\,Si II}\approx(5.7-8.6)\,\times 10^{5} M_{\odot}$, outflow rate of $\dot{M}_{\rm outflow}\gtrsim0.02 M_{\odot}\,\text{yr}^{-1}$, and mass loading factor of $η\gtrsim0.10$ within 0.52 degrees from the center of 30 Doradus. The observed ion ratios$-$together with photoionization modeling$-$reveal that this wind is roughly $40-97\%$ photoionized. The metallicities and dust depletion patterns of the high-velocity absorbers at $v_{\rm LSR}\approx+120\,\text{km}\,\text{s}^{-1}$ can be explained by either a foreground Milky Way (MW) halo cloud or an outflow from the LMC. For the high-ions, Si IV and C IV are broader and kinematically offset from the low-ions, suggesting turbulent mixing layers (TMLs) existing in the wind. Finally, our hydrodynamical simulations of the Magellanic Clouds (MCs) and MW system suggest that the Magellanic Corona can protect the LMC winds from the ram-pressure forces exerted by the MW's halo.

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arXiv2025

Star Formation History of the Local Group Dwarf Irregular Galaxy, NGC 6822

NGC 6822 is an isolated dwarf irregular galaxy in the local group at a distance of 490 kpc. In this paper, we present the star formation history (SFH) within a field with a radius of 3 kpc, beyond the optical body of the galaxy (1.2 kpc). We utilized a novel method based on evolved asymptotic giant branch (AGB) stars. We collected the Near infrared data of 329 variable stars, including long-period and amplitude variables and Carbon-rich AGB stars. We used stellar evolutionary track and theoretical isochrones to obtain the birth mass, age, and pulsation duration of the detected stars to calculate the star formation rate (SFR) and trace the SFH of the galaxy. We studied the star formation history of the galaxy for the mean metallicity value (Z) of 0.003. We reconstructed the SFH for two regions. The bar region, a central rectangular area, and the outer region, which covers a circular field beyond the bar region and extends to a radius of 3 kpc. Our results show a significant burst of star formation around 2.6 and 2.9 Gyr ago in the bar and outer regions, respectively. Additionally, we observed a notable enhancement in the SFR in the bar region over the past 200 Myr.

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arXiv2025

Equatorial Enhancement in the Dustiest OH/IR Stars in the Galactic Bulge

We have detected the 10 um silicate feature and the 11.3 um crystalline forsterite feature in absorption in 21 oxygen-rich AGB stars in the Galactic Bulge. The depths of the 10 um feature indicate highly-obscured circumstellar environments. The additional crystalline features may suggest either an extended envelope or dust formation in a high-density environment. We have also modeled the Spectral Energy Distributions of the sample using radiative transfer models, and compared the results to wind speeds measured using 1612 MHz circumstellar OH masers, as well as previous estimates of circumstellar properties. The sixteen sources with measured pulsation periods appear on sequence D of the mid-infrared Period-Luminosity relation, associated with the Long Secondary Period. We suspect that all of these sources are in fact fundamental mode pulsators. At least two sources appear on the fundamental mode sequence when accounting for the dust content. For the remainder, these sources are also likely fundamental mode pulsators with extended envelopes. Taken as a whole, the high optical depths, crystalline features, discrepancies between observed and modeled wind speeds, pulsation periods longer than other fundamental mode pulsators, and SED and pulsation properties similar to those with known equatorially-enhanced circumstellar envelopes (e.g. OH 26.5+0.6 and OH 30.1-0.7) lead us to believe that these sources are likely to be equatorially-enhanced.

astro-ph.SR↗

arXiv2025

Considerations with stacking absorption spectra: cold HI gas in cirrus region of the Milky Way

We use the Milky Way neutral hydrogen (HI) absorption and emission spectra from the Galactic Australian Square Kilometre Array Pathfinder (GASKAP) Phase II Pilot survey along with toy models to investigate the effects of stacking multicomponent spectra on measurements of peak optical depth and spin temperature. Shifting spectra by the peak in emission, 'primary' components shifted to 0 km s$^{-1}$ are correctly averaged. Additional components on individual sightlines are averaged with non-centred velocities, producing a broader and shallower 'secondary' component in the resulting stack. Peak optical depths and brightness temperatures of the secondary components from stacks are lower limits of their true average values due to the velocity offset of each component. The spin temperature however is well correlated with the truth since the velocity offset of components affects the emission and absorption spectra equally. Stacking 462 GASKAP absorption-emission spectral pairs, we detect a component with a spin temperature of 1320 $\pm$ 263 K, consistent with gas from the unstable neutral medium and higher than any previous GASKAP detection in this region. We also stack 2240 pilot survey spectra containing no Milky Way absorption, revealing a primary narrow and secondary broad component, with spin temperatures belonging to the cold neutral medium (CNM). Spatially binning and stacking the non-detections across the plane-of-sky by their distance from CNM absorption detections, the primary component's optical depth decreases with distance from known locations of cold gas. The spin temperature however remains stable in both components, over an approximate physical plane-of-sky distance of $\sim$ 100 pc.

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arXiv2025

The VMC Survey : LI. Classifying extragalactic sources using a probabilistic random forest supervised machine learning algorithm

We used a supervised machine learning algorithm (probabilistic random forest) to classify ~130 million sources in the VISTA Survey of the Magellanic Clouds (VMC). We used multi-wavelength photometry from optical to far-infrared as features to be trained on, and spectra of Active Galactic Nuclei (AGN), galaxies and a range of stellar classes including from new observations with the Southern African Large Telescope (SALT) and SAAO 1.9m telescope. We also retain a label for sources that remain unknown. This yielded average classifier accuracies of ~79% (SMC) and ~87% (LMC). Restricting to the 56,696,719 sources with class probabilities (P$_{class}$) > 80% yields accuracies of ~90% (SMC) and ~98% (LMC). After removing sources classed as 'Unknown', we classify a total of 707,939 (SMC) and 397,899 (LMC) sources, including > 77,600 extragalactic sources behind the Magellanic Clouds. The extragalactic sources are distributed evenly across the field, whereas the Magellanic sources concentrate at the centres of the Clouds, and both concentrate in optical/IR colour-colour/magnitude diagrams as expected. We also test these classifications using independent datasets, finding that, as expected, the majority of X-ray sources are classified as AGN (554/883) and the majority of radio sources are classed as AGN (1756/2694) or galaxies (659/2694), where the relative AGN-galaxy proportions vary substantially with radio flux density. We have found: > 49,500 hitherto unknown AGN candidates, likely including more AGN dust dominated sources which are in a critical phase of their evolution; > 26,500 new galaxy candidates and > 2800 new Young Stellar Object (YSO) candidates.

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arXiv2024

Deciphering Galactic Halos: A Detailed Review of Star Formation in NGC 5128 (Cen A)

NGC 5128 (Centaurus A), the closest giant elliptical galaxy outside the Local Group to the Milky Way, is one of the brightest extragalactic radio sources. It is distinguished by a prominent dust lane and powerful jets, driven by a supermassive black hole at its core. Using previously identified long-period variable (LPV) stars from the literature, this study aims to reconstruct the star formation history (SFH) of two distinct regions in the halo of NGC 5128. These regions reveal remarkably similar SFHs, despite being located about 28 kpc apart on opposite sides of the galaxy's center. In Field 1, star formation rates (SFRs) show notable increases at approximately 800 Myr and 3.8 Gyr ago. Field 2 exhibits similar peaks at these times, along with an additional rise around 6.3 Gyr ago. The increase in SFR around 800 Myr ago is consistent with earlier research suggesting a merger event. Since no LPV catalog exists for the central region of NGC 5128, we focused our investigation on its outer regions, which has provided new insights into the complex evolutionary history of this cornerstone galaxy. The SFH traced by LPVs supports a scenario in which multiple events of nuclear activity have triggered episodic, jet-induced star formation.

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arXiv2024

Processing of GASKAP-HI pilot survey data using a commercial supercomputer

Modern radio telescopes generate large amounts of data, with the next generation Very Large Array (ngVLA) and the Square Kilometre Array (SKA) expected to feed up to 292 GB of visibilities per second to the science data processor (SDP). However, the continued exponential growth in the power of the world's largest supercomputers suggests that for the foreseeable future there will be sufficient capacity available to provide for astronomers' needs in processing 'science ready' products from the new generation of telescopes, with commercial platforms becoming an option for overflow capacity. The purpose of the current work is to trial the use of commercial high performance computing (HPC) for a large scale processing task in astronomy, in this case processing data from the GASKAP-HI pilot surveys. We delineate a four-step process which can be followed by other researchers wishing to port an existing workflow from a public facility to a commercial provider. We used the process to provide reference images for an ongoing upgrade to ASKAPSoft (the ASKAP SDP software), and to provide science images for the GASKAP collaboration, using the joint deconvolution capability of WSClean. We document the approach to optimising the pipeline to minimise cost and elapsed time at the commercial provider, and give a resource estimate for processing future full survey data. Finally we document advantages, disadvantages, and lessons learned from the project, which will aid other researchers aiming to use commercial supercomputing for radio astronomy imaging. We found the key advantage to be immediate access and high availability, and the main disadvantage to be the need for improved HPC knowledge to take best advantage of the facility.

astro-ph.IM↗

arXiv2024

Detection of the Long Period Variable Stars of And II Dwarf Satellite galaxy

We conducted an extensive study of the spheroidal dwarf satellite galaxies around the Andromeda galaxy to produce an extensive catalog of LPV stars. The optical monitoring project consists of 55 dwarf galaxies and four globular clusters that are members of the Local Group. We have made observations of these galaxies using the WFC mounted on the 2.5 m INT in nine different periods, both in the i-band filter Sloan and in the filter V-band Harris. We aim to select AGB stars with brightness variations larger than 0.2 mag to investigate the evolutionary processes in these dwarf galaxies. The resulting catalog of LPV stars in Andromeda's satellite galaxies offers updated information on features like half-light radii, TRGB magnitudes, and distance moduli. This manuscript will review the results obtained for And II galaxy. Using the Sobel filter, we have calculated the distance modulus for this satellite galaxy, which ranges from 23.90 to 24.11 mag.

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arXiv2024

An automated method to detect and characterise semi-resolved star clusters

We present a novel method for automatically detecting and characterising semi-resolved star clusters: clusters where the observational point-spread function (PSF) is smaller than the cluster's radius, but larger than the separations between individual stars. We apply our method to a 1.77 deg$^2$ field located in the Large Magellanic Cloud (LMC) using the VISTA survey of the Magellanic Clouds (VMC), which surveyed the LMC in the $YJK_\text{s}$ bands. Our approach first models the position-dependent PSF to detect and remove point sources from deep $K_\text{s}$ images; this leaves behind extended objects such as star clusters and background galaxies. We then analyse the isophotes of these extended objects to characterise their properties, perform integrated photometry, and finally remove any spurious objects this procedure identifies. We demonstrate our approach in practice on a deep VMC $K_\text{s}$ tile that contains the most active star-forming regions in the LMC: 30 Doradus, N158, N159, and N160. We select this tile because it is the most challenging for automated techniques due both to crowding and nebular emission. We detect 682 candidate star clusters, with an estimated contamination rate of 13% from background galaxies and chance blends of physically unrelated stars. We compare our candidates to publicly available James Webb Space Telescope data and find that at least 80% of our detections appear to be star clusters.

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