82 citations · 358 across the 17 of their papers we have counts for
17 papers
A time-series VI study of the variable stars of the globular cluster NGC 6397
J. A. Ahumada, A. Arellano Ferro, I. Bustos Fierro +4
We present a new time-series VI CCD photometry of the globular cluster NGC 6397, from which we obtained and analysed the light curves of 35 variables carefully identified in the cl…
A new, Gaia based, catalogue of blue straggler stars in open clusters
M. J. Rain, J. Ahumada, G. Carraro
Blue straggler stars are exotic objects present in all stellar environments whose nature and formation channels are still partially unclear. They seem to be particularly abundant i…
Variability in NGC 3201 giant stars and its impact on their spectroscopic [Fe/H] determination
Á. Llancaqueo Albornoz, S. Villanova, C. C. Cortés +2
We present the analysis of 34 light curves in and of 17 giant stars in the globular cluster NGC 3201, to check if such stars are variable and if their variability has some…
The blue straggler population of the open clusters Trumpler 5, Trumpler 20, and NGC 2477
M. J Rain, G. Carraro, J. Ahumada +3
We present a study, based on Gaia DR2, of the population of blue straggler stars (BSS) in the open clusters Trumpler 5, Trumpler 20, and NGC 2477. All candidates were selected acco…
A study of the blue straggler population of the old open cluster Collinder 261
M. J. Rain, G. Carraro, J. A. Ahumada +4
Blue Stragglers are stars located in an unexpected region of the color-magnitude diagram of a stellar population, as they appear bluer and more luminous than the stars in the turno…
Hunting white dwarfs at the center of planetary nebulae
Javier Ahumada, Walter Weidmann, Marcelo Miller Bertolami +1
We present Gemini-South observations of nine faint and extended planetary nebulae. Using direct images taken with the spectrograph GMOS, we built the vs. di…
NGC 1261: A time-series \emph{VI} study of its variable stars
A. Arellano Ferro, I. H. Bustos Fierro, J. H. Calderón +1
Time-series \emph{VI} CCD photometry of the globular cluster NGC 1261 is employed to study its variable star population. A membership analysis of most variables based on Gaia~DR2 p…
Metallicity and distance of NGC 6362 from its RR Lyrae and SX Phoenicis stars
A. Arellano Ferro, J. A. Ahumada, I. H. Bustos Fierro +2
New time-series VI CCD photometry of the globular cluster NGC 6362 is studied with the aim of estimating the reddening, mean metallicity and distance of the cluster from its popula…
A New Overview of Secular Period Changes of RR Lyrae stars inM5
A. Arellano Ferro, J. A. Ahumada, N. Kains +1
Secular period variations, , in 76 RR Lyrae stars in the globular cluster M5 are analysed using our most recent CCD photometry and the historical photometric databas…
Atlas of monochromatic images of planetary nebulae
W. A. Weidmann, E. O. Schmidt, R. R. Vena Valdarenas +3
We present an atlas of more than one hundred original images of planetary nebulae (PNe). These images were taken in a narrow-band filter centred on the nebular emission of the [N I…
RR Lyrae stars and the horizontal branch of NGC 5904 (M5)
A. Arellano Ferro, A. Luna, D. M. Bramich +3
We report the distance and [Fe/H] value for the globular cluster NGC 5904 (M5) derived from the Fourier decomposition of the light curves of selected RRab and RRc stars. The aim in…
Revisiting the variable star population in NGC~6229 and the structure of the Horizontal Branch
A. Arellano Ferro, P. E. Mancera Piña, D. M. Bramich +4
We report an analysis of new and CCD time-series photometry of the distant globular cluster NGC 6229. The principal aims were to explore the field of the cluster in search…
The thickening of the thin disk in the third Galactic quadrant
Giovanni Carraro, Ruben A. Vazquez, Edgardo Costa +2
In the third Galactic quadrant (180 < l < 270) of the Milky Way, the Galactic thin disk exhibits a significant warp ---shown both by gas and young stars--- bending down a few kpc b…
Fourier Decomposition of RR Lyrae light curves and the SX Phe population in the central region of NGC 3201
A. Arellano Ferro, J. A. Ahumada, J. H. Calderón +1
CCD time-series observations of the central region of the globular cluster NGC~3201 were obtained with the aim of performing the Fourier decomposition of the light curves of the RR…
A super lithium-rich red-clump star in the open cluster Trumpler 5
L. Monaco, H. M. J. Boffin, P. Bonifacio +7
Context. The existence of lithium-rich low-mass red giant stars still represents a challenge for stellar evolution models. Stellar clusters are privileged environments for this kin…
Chemical abundance analysis of the old, rich open cluster Trumpler 20
Giovanni Carraro, Sandro Villanova, Lorenzo Monaco +3
Trumpler 20 is an open cluster located at low Galactic longitude, just beyond the great Carina spiral arm, and whose metallicity and fundamental parameters were very poorly known u…
Photometric characterization of the Galactic star cluster Trumpler 20
Giovanni Carraro, Edgardo Costa, Javier Ahumada
We present deep UBVI photometry for Trumpler 20, a rich, intermediate-age open cluster located at l=301.47, b=+2.22 (RA=12:39:34, DEC=-60:37:00, J2000.0) in the fourth Galactic qua…