134 citations · 2.1k across the 59 of their papers we have counts for
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Tracing stellar rotation in young massive LMC clusters
Sebastian Kamann, Nate Bastian, Florian Niederhofer +8
We present a detailed analysis of stellar rotation along the main sequences of NGC 1866 and NGC 1856, two young (~200-300 Myr) massive clusters in the Large Magellanic Cloud, using…
The effects of stellar rotation along the main sequence of the 100 Myr old massive cluster NGC 1850
Sebastian Kamann, Sara Saracino, Nate Bastian +13
Young star clusters enable us to study the effects of stellar rotation on an ensemble of stars of the same age and across a wide range in stellar mass and are therefore ideal targe…
Exploring the role of binarity in the origin of the bimodal rotational velocity distribution in stellar clusters
S. Kamann, N. Bastian, C. Usher +2
Many young and intermediate age massive stellar clusters host bimodal distributions in the rotation rates of their stellar populations, with a dominant peak of rapidly rotating sta…
Leveraging HST with MUSE: II. Na-abundance variations in intermediate age star clusters
S. Martocchia, S. Kamann, S. Saracino +13
Ancient (10 Gyr) globular clusters (GCs) show chemical abundance variations in the form of patterns among certain elements, e.g. N correlates with Na and anti-correlates with O.…
Leveraging HST with MUSE: I. Sodium abundance variations within the 2 Gyr-old cluster NGC 1978
S. Saracino, S. Kamann, C. Usher +10
Nearly all of the well studied ancient globular clusters (GCs), in the Milky Way and in nearby galaxies, show star-to-star variations in specific elements (e.g., He, C, N, O, Na, A…
Searching for Multiple Populations in the Integrated Light of the Young and Extremely Massive Clusters in the Merger Remnant NGC~7252
Nate Bastian, Carmela Lardo, Christopher Usher +8
Recent work has shown that the properties of multiple populations within massive stellar clusters (i.e., in the extent of their abundance variations as well as the fraction of star…
Chromosome maps of young LMC clusters: An additional case of coeval multiple populations
S. Saracino, S. Martocchia, N. Bastian +9
Recent studies have revealed that the Multiple Populations (MPs) phenomenon does not occur only in ancient and massive Galactic globular clusters (GCs), but it is also observed in…
How stellar rotation shapes the colour magnitude diagram of the massive intermediate-age star cluster NGC 1846
Sebastian Kamann, Nate Bastian, Seth Gossage +19
We present a detailed study of stellar rotation in the massive 1.5 Gyr old cluster NGC 1846 in the Large Magellanic Cloud. Similar to other clusters at this age, NGC 1846 shows an…
Extended main sequence turnoffs in open clusters as seen by Gaia -- II. The enigma of NGC 2509
M. de Juan Ovelar, S. Gossage, S. Kamann +5
We investigate the morphology of the colour-magnitude diagram (CMD) of the open cluster NGC 2509 in comparison with other Galactic open clusters of similar age using Gaia photometr…
An Extragalactic Chromosome Map: The intermediate age SMC Cluster Lindsay 1
S. Saracino, N. Bastian, V. Kozhurina-Platais +8
The discovery of star-to-star abundance variations (a.k.a. multiple populations - MPs) within globular clusters (GCs), which are generally not found in the field or in lower mass o…
Combined Effects of Rotation and Age Spreads on Extended Main Sequence Turn Offs
Seth Gossage, Charlie Conroy, Aaron Dotter +10
The extended main sequence turn offs (eMSTOs) of several young to intermediate age clusters are examined in the Magellanic Clouds and the Milky Way. We explore the effects of exten…
The search for multiple populations in Magellanic Clouds clusters - V. Correlation between cluster age and abundance spreads
S. Martocchia, E. Dalessandro, C. Lardo +14
In our HST photometric survey, we have been searching for multiple stellar populations (MPs) in Magellanic Clouds (MCs) massive star clusters which span a significant range of ages…
Disappearance of the extended main sequence turn-off in intermediate age clusters as a consequence of magnetic braking
C. Georgy, C. Charbonnel, L. Amard +8
Extended MS turn-offs are features commonly found in the colour-magnitude diagrams of young and intermediate age (less than about 2 Gyr) massive star clusters, where the MS turn-of…
Extended Main Sequence Turnoffs in Open Clusters as Seen by Gaia: I. NGC 2818 and the Role of Stellar Rotation
N. Bastian, S. Kamann, I. Cabrera-Ziri +5
We present an analysis of the relatively low mass (~M), ~Myr, Galactic open cluster, NGC~2818, using Gaia DR2 results combined with VLT/FLAMES spectros…
A critical re-evaluation of the Thorne-Żytkow object candidate HV 2112
Emma R. Beasor, Ben Davies, Ivan Cabrera-Ziri +1
It has been argued in the literature that the star HV~2112 in the Small Magellanic Cloud is the first known example of a TŻO, a Red Supergiant with a degenerate neutron core. This…
Chemical Inhomogeneities Amongst First Population Stars in Globular Clusters: Evidence for He variations
Carmela Lardo, Maurizio Salaris, Nate Bastian +3
Spreads in light element abundances among stars (a.k.a. multiple populations) are observed in nearly all globular clusters. One way to map such chemical variations using high-preci…
The search for multiple populations in Magellanic Cloud Clusters IV: Coeval multiple stellar populations in the young star cluster NGC 1978
S. Martocchia, F. Niederhofer, E. Dalessandro +15
We have recently shown that the Gyr old Large Magellanic Cloud star cluster NGC 1978 hosts multiple populations in terms of star-to-star abundance variations in [N/Fe]. The…
The Search for Multiple Populations in Magellanic Cloud Clusters II: The Detection of Multiple Populations in Three Intermediate-Age SMC Clusters
F. Niederhofer, N. Bastian, V. Kozhurina-Platais +14
This is the second paper in our series about the search for multiple populations in Magellanic Cloud star clusters using the Hubble Space Telescope. Here we report the detection of…
The Search for Multiple Populations in Magellanic Cloud Clusters I: Two Stellar Populations in the Small Magellanic Cloud Globular Cluster NGC 121
F. Niederhofer, N. Bastian, V. Kozhurina-Platais +14
We started a photometric survey using the WFC3/UVIS instrument onboard the Hubble Space Telescope to search for multiple populations within Magellanic Cloud star clusters at variou…
Controversial Age Spreads from the Main Sequence Turn-Off and Red Clump in Intermediate-Age Clusters in the LMC
F. Niederhofer, N. Bastian, V. Kozhurina-Platais +5
Most star clusters at an intermediate age (1-2 Gyr) in the Large and Small Magellanic Clouds show a puzzling feature in their color-magnitude diagrams (CMD) that is not in agreemen…