168 citations · 737 across the 34 of their papers we have counts for
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TIC441725813: A new bright hybrid sdB pulsator with differential core/envelope rotation
Wenchao Su, Stéphane Charpinet, Marilyn Latour +3
We present the detailed analysis of a new hybrid (p- and g-mode) sdB pulsator, TIC441725813 (TYC 4427-1021-1), discovered and monitored by TESS over 670 days. The TESS light curves…
SHOTGLAS II. MUSE spectroscopy of blue horizontal branch stars in the core of Centauri and NGC 6752
M. Latour, S. Hämmerich, M. Dorsch +5
In this work, we characterize the properties of HB stars in the GCs Cen and NGC 6752. We use dedicated model atmospheres and synthetic spectra grids computed using a hybrid LTE…
A stellar census in globular clusters with MUSE. A new perspective on the multiple main sequences of Centauri
M. Latour, A. Calamida, T. -O. Husser +3
Cen is a rare example of a globular cluster where the iron abundance of the stars spans more than one order of magnitude. Many spectroscopic investigations of its red-giant- an…
On the Use of Field RR Lyrae as Galactic Probes. V. Optical and radial velocity curve templates
V. F. Braga, J. Crestani, M. Fabrizio +29
We collected the largest spectroscopic catalog of RR Lyrae (RRLs) including 20,000 high-, medium- and low-resolution spectra for 10,000 RRLs. We provide the analy…
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.…
Heavy-metal enrichment of intermediate He-sdOB stars: the pulsators Feige 46 and LS IV -14 116 revisited
M. Dorsch, M. Latour, U. Heber +3
Hot subdwarf stars of types O and B represent a poorly understood phase in the evolution of low-mass stars. Many subdwarfs show rich oscillations and are among the most chemically…
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…
A stellar census in globular clusters with MUSE -- Extending the CaT-metallicity relation below the horizontal branch and applying it to multiple populations
Tim-Oliver Husser, Marilyn Latour, Jarle Brinchmann +7
Aims. We use the spectra of more than 30,000 red giant branch (RGB) stars in 25 globular clusters (GC), obtained within the MUSE survey of Galactic globular clusters, to calibrate…
The binary content of multiple populations in NGC 3201
Sebastian Kamann, Benjamin Giesers, Nate Bastian +7
We investigate the binary content of the two stellar populations that coexist in the globular cluster NGC 3201. Previous studies of binary stars in globular clusters have reported…
A stellar census in globular clusters with MUSE: Multiple populations chemistry in NGC 2808
M. Latour, T. -O. Husser, B. Giesers +8
Galactic globular clusters (GCs) are now known to host multiple populations displaying particular abundance variations. The different populations within a GC can be well distinguis…
A stellar census in globular clusters with MUSE: Binaries in NGC 3201
Benjamin Giesers, Sebastian Kamann, Stefan Dreizler +8
We utilize multi-epoch MUSE spectroscopy to study binaries in the core of NGC 3201. Our sample consists of 3553 stars with 54883 spectra in total comprising 3200 main-sequence star…
Heavy-metal enrichment in the intermediate He-sdOB pulsator Feige 46
Marilyn Latour, Matti Dorsch, Ulrich Heber
The intermediate He-enriched hot subdwarf star Feige 46 was recently reported as the second member of the V366 Aqr (or He-sdOBV) pulsating class. Feige 46 is very similar to the pr…
Heavy metals in intermediate He-rich hot subdwarfs: The chemical composition of HZ44 and HD127493
Matti Dorsch, Marilyn Latour, Ulrich Heber
Hot subluminous stars can be spectroscopically classified as subdwarf B (sdB) and O (sdO) stars. While the latter are predominantly hydrogen deficient, the former are mostly helium…
PB 8783: the first sdO star suitable for asteroseismic modeling?
Valerie Van Grootel, Suzanna K. Randall, Marilyn Latour +5
Pulsating hot B subdwarf (sdB) stars, which are core-He burning objects, are one of the showcases of asteroseismology. Thanks to the combination of rich pulsation spectra and state…
Discovery of a second pulsating intermediate helium-enriched sdOB star
M. Latour, E. M. Green, G. Fontaine
We present the discovery of long-period, low-amplitude, g-mode pulsations in the intermediate He-rich hot subdwarf (sdOB) star Feige 46. Up until now only one other He-enriched sdO…
A quantitative NLTE analysis of visual and ultraviolet spectra of four helium-rich subdwarf O stars
Markus Schindewolf, Peter Nemeth, Ulrich Heber +4
Hot subdwarfs represent a poorly understood late phase of stellar evolution. While binary evolution plays an important role for B-subdwarfs (sdB), the origin of the He dominated O-…
SHOTGLAS I: The ultimate spectroscopic census of extreme horizontal branch stars in Centauri
Marilyn Latour, Suzanna K. Randall, Annalisa Calamida +2
The presence of extreme horizontal branch (EHB) and blue hook stars in some Galactic globular clusters (GGCs) constitutes one of the remaining mysteries of stellar evolution. In th…
Rotational broadening and conservation of angular momentum in post-extreme horizontal branch stars
G. Fontaine, M. Latour
We show that the recent realization that isolated post-extreme horizontal branch (post-EHB) stars are generally characterized by rotational broadening with values of $V_{\rm rot} \…
Spectral analysis of the He-enriched sdO-star HD 127493
Matti Dorsch, Marilyn Latour, Ulrich Heber
The bright sdO star HD 127493 is known to be of mixed H/He composition and excellent archival spectra covering both optical and ultraviolet ranges are available. UV spectra play a…
Spectral analysis of four surprisingly similar hot hydrogen-rich subdwarf O stars
M. Latour, P. Chayer, E. M. Green +2
We perform a comprehensive spectroscopic analysis of four such bright sdO stars, namely Feige 34, Feige 67, AGK81 266, and LS II18 9, among which the first three are used as…
Observations of the Ultraviolet-Bright Star Y453 in the Globular Cluster M4 (NGC 6121)
William V. Dixon, Pierre Chayer, Marilyn Latour +2
We present a spectral analysis of the UV-bright star Y453 in M4. Model fits to the star's optical spectrum yield T_eff ~ 56,000 K. Fits to the star's FUV spectrum, obtained with th…
Blue large-amplitude pulsators as a new class of variable stars
P. Pietrukowicz, W. A. Dziembowski, M. Latour +13
Regular intrinsic brightness variations observed in many stars are caused by pulsations. These pulsations provide information on the global and structural parameters of the star. T…
Just how hot are the Centauri extreme horizontal branch pulsators?
M. Latour, S. K. Randall, P. Chayer +5
Past studies based on optical spectroscopy suggest that the five Cen pulsators form a rather homogeneous group of hydrogen-rich subdwarf O stars with effective temperatures of…
Spectral analysis of the sdO standard star Feige 34
M. Latour, P. Chayer, E. M. Green +1
We present our current work on the spectral analysis of the hot sdO star Feige 34. We combine high S/N optical spectra and fully-blanketed non-LTE model atmospheres to derive its f…