215 citations · 1.7k across the 64 of their papers we have counts for
23 papers · 1 filter
New Optical and Mid-Infrared RR Lyrae Period-Luminosity-Metallicity Relations for Precision Distances and Metallicity Distributions in the Magellanic Clouds
Clara E. Martínez-Vázquez, Joseph P. Mullen, Massimo Marengo +11
RR Lyrae (RRL) stars, thanks to the existence of their period-luminosity relations, have been widely used as primary standard candles within the Milky Way and the Local Group of ga…
Spectroscopic metallicities and first α-element abundances of RR Lyrae stars in Baade's Window
J. Olivares Carvajal, Á. Rojas-Arriagada, M. Zoccali +10
RR Lyrae stars in the bulge have been reported to be associated with the spheroidal, relatively metal-poor component. They offer a way to trace this component with precise distance…
On the Use of Field RR Lyrae as Galactic Probes -- VIII. Early Formation of the Galactic Spheroid
G. Bono, V. F. Braga, M. Fabrizio +54
We introduce a new photometric catalog of RR Lyrae variables (RRLs, 300,000) mainly based on data available in public datasets. We also present the largest and most homogeneo…
Classical Cepheids in the Galactic thin disk I. Abundance gradients via non-local thermodynamic equilibrium spectral analysis
Antonino Nunnari, Valentina D'Orazi, Giuliana Fiorentino +23
Classical Cepheids (CCs) have long been considered excellent tracers of the chemical evolution of the Milky Way's young disk. We present a homogeneous, NLTE spectroscopic analysis…
The dwarf irregular galaxy NGC 6822. II. Young, intermediate and old stellar populations: comparison between theory and observations
Maria Tantalo, Giuseppe Bono, Maurizio Salaris +14
This paper presents a quantitative analysis of the stellar content in the Local Group dwarf irregular galaxy NGC 6822 by comparing stellar evolution models and observations in colo…
The GALAH survey: Tracing the Milky Way's formation and evolution through RR Lyrae stars
Valentina D'Orazi, Nicholas Storm, Andrew R. Casey +39
Stellar mergers and accretion events have been crucial in shaping the evolution of the Milky Way (MW). These events have been dynamically identified and chemically characterised us…
Oxygen, sulfur, and iron radial abundance gradients of classical Cepheids across the Galactic thin disk
R. da Silva, V. D'Orazi, M. Palla +25
Classical Cepheids (CCs) are solid distance indicators and tracers of young stellar populations. Our aim is to provide iron, oxygen, and sulfur abundances for the largest and most…
RR Lyrae mid-infrared Period-Luminosity-Metallicity and Period-Wesenheit-Metallicity relations based on Gaia DR3 parallaxes
Joseph P. Mullen, Massimo Marengo, Clara E. Martínez-Vázquez +8
We present new empirical infrared Period-Luminosity-Metallicity (PLZ) and Period-Wesenheit-Metallicity (PWZ) relations for RR Lyrae based on the latest Gaia EDR3 parallaxes. The re…
On the Use of Field RR Lyrae as Galactic Probes. VI. Mixed mode RR Lyrae variables in Fornax and in nearby dwarf galaxies
V. F. Braga, G. Fiorentino, G. Bono +11
We investigate the properties of the mixed-mode (RRd) RR Lyrae (RRL) variables in the Fornax dwarf spheroidal (dSph) galaxy by using - and -band time series collected over tw…
Tracing the Milky Way warp and spiral arms with classical Cepheids
B. Lemasle, H. N. Lala, V. Kovtyukh +10
Mapping the Galactic spiral structure is a difficult task since the Sun is located in the Galactic plane and because of dust extinction. For these reasons, molecular masers in radi…
Milky Way archaeology using RR Lyrae and type II Cepheids II. High velocity RR Lyrae stars, and mass of the Milky Way
Z. Prudil, A. J Koch-Hansen, B. Lemasle +10
We report the discovery of high velocity candidates among RR~Lyrae stars found in the Milky Way halo. We identified 9 RR~Lyrae stars with Galactocentric velocities exceeding the lo…
On the dwarf irregular galaxy NGC 6822. I. Young, intermediate and old stellar populations
Maria Tantalo, Massimo Dall'Ora, Giuseppe Bono +13
We present accurate and deep multi-band () photometry of the Local Group dwarf irregular galaxy NGC 6822. The images were collected with wide field cameras at 2m/4m- (INT,CT…
Milky Way archaeology using RR Lyrae and type II Cepheids I. The Orphan stream in 7D using RR Lyrae stars
Z. Prudil, M. Hanke, B. Lemasle +19
We present a chemo-dynamical study of the Orphan stellar stream using a catalog of RR~Lyrae pulsating variable stars for which photometric, astrometric, and spectroscopic data are…
Using classical Cepheids to study the far side of the Milky Way disk: I. Spectroscopic classification and the metallicity gradient
J. H. Minniti, L. Sbordone, A. Rojas-Arriagada +9
The structure, kinematics, and chemical composition of the far side of the Milky Way disk, beyond the bulge, are still to be revealed. Classical Cepheids (CCs) are young and lumino…
Metallicity Distribution of Galactic Halo Field RR Lyrae, and the Effect of Metallicity on their Pulsation Properties
M. Marengo, J. P. Mullen, J. R. Neeley +14
We present our analysis of a large sample (over 150k) of candidate Galactic RR Lyrae (RRL) stars for which we derived high quality photometry at UV, optical and infrared wavelength…
A DECam View of the Diffuse Dwarf Galaxy Crater II: Variable Stars
A. Katherina Vivas, Alistair R. Walker, Clara E. Martínez-Vázquez +11
Time series observations of a single dithered field centered on the diffuse dwarf satellite galaxy Crater II were obtained with the Dark Energy Camera (DECam) at the 4m Blanco Tele…
Structure and kinematics of Type II Cepheids in the Galactic bulge based on near-infrared VVV data
V. F. Braga, A. Bhardwaj, R. Contreras Ramos +5
Type II Cepheids (T2Cs) are radially pulsating variables that trace old stellar populations and provide distance estimates through their period-luminosity (PL) relation. We trace t…
Old-Aged Stellar Population Distance Indicators
Rachael L. Beaton, Giuseppe Bono, Vittorio Francesco Braga +8
Old-aged stellar distance indicators are present in all Galactic structures (halo, bulge, disk) and in galaxies of all Hubble types and, thus, are immensely powerful tools for unde…
Impact of distance determinations on Galactic structure. II. Old tracers
A. Kunder, E. Valenti, M. Dall'Ora +14
Here we review the efforts of a number of recent results that use old tracers to understand the build up of the Galaxy. Details that lead directly to using these old tracers to mea…
Weak Galactic Halo--Fornax dSph Connection from RR Lyrae Stars
G. Fiorentino, M. Monelli, P. B. Stetson +7
For the first time accurate pulsation properties of the ancient variable stars of the Fornax dwarf spheroidal galaxy (dSph) are discussed in the broad context of galaxy formation a…
On the distance of the globular cluster M4 (NGC 6121) using RR Lyrae stars: I. optical and near-infrared Period-Luminosity and Period-Wesenheit relations
V. F. Braga, M. Dall'Ora, G. Bono +16
We present new distance determinations to the nearby globular M4 (NGC~6121) based on accurate optical and Near Infrared (NIR) mean magnitudes for fundamental (FU) and first overton…
Continuum reverberation mapping in a z = 1.41 radio-loud quasar
L. J. Goicoechea, V. N. Shalyapin, R. Gil-Merino +1
Q0957+561 was the first discovered gravitationally lensed quasar. The mirage shows two images of a radio-loud quasar at redshift z = 1.41. The time lag between these two images is…
Accretion Onto the Supermassive Black Hole in the High-redshift Radio-loud AGN 0957+561
Rodrigo Gil-Merino, Luis J. Goicoechea, Vyacheslav N. Shalyapin +1
We present the results of our X-ray, UV and optical monitoring campaign of the first gravitationally lensed AGN from late 2009 to mid 2010. The trailing (B) image of the AGN 0957+5…