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51. Structure and stellar content analysis of the open cluster M11 with 2MASS photometry

Author

Santos Jr., J. F. C., Bonatto, C., and Bica, E.

Subjects
Astrophysics
Abstract

An overall analysis of the structure and stellar content of M11 is presented, thanks to the wide-angle 2MASS spatial coverage. We derive photometric and structural parameters and discuss the spatial dependance of the luminosity and mass functions. Photometric parameters basically agree with previous ones mostly based on the optical. We obtained a core radius of 1.23pc and a tidal radius of 29pc. In particular, the cluster is populous enough so that the tidal radius could be obtained by fitting the three-parameter King profile to the radial distribution of stars. We analyzed the spatial distribution of mass functions, finding that the the slope changes from -0.73 in the core to +2.88 in the outer halo. The spatial distribution of mass function slopes derived from 2MASS agrees with that derived from optical CCD data, which further confirms the reliability of 2MASS data for future analyses of this kind at comparable observational limits. We detect mass segregation up to distances from the center of ~20arcmin. We emphasize that the mass function slope in the core is flatter than anywhere else as a consequence of mass segregation. The derived total cluster mass is ~11000 solar masses., Comment: 9 pages, 11 figures. Accepted for publication in A&A

Published
2005
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52. Spatial dependence of 2MASS luminosity and mass functions in the old open cluster NGC 188

Author

Bonatto, C., Bica, E., and Santos Jr, J. F. C.

Subjects
Astrophysics
Abstract

Luminosity and mass functions in the old open cluster NGC 188 are analysed by means of J and H 2MASS photometry. Within the uncertainties, the observed projected radial density profile of NGC 188 departs from the two-parameter King model in two inner regions, which reflects the non-virialized dynamical state and possibly, some degree of non-sphericity in the spatial shape of this old open cluster. Fits with two and three-parameter King models to the radial distribution of stars resulted in a core radius of 1.3 pc and a tidal radius of 21 pc. The present 2MASS analysis resulted in significant slope variations with distance in the mass function $\phi(m)\propto m^{-(1+\chi)}$, being flat in the central parts ($\chi=0.6\pm0.7$) and steep in the cluster outskirts ($\chi=7.2\pm0.6$). The overall mass function has a slope $\chi=1.9\pm0.7$, slightly steeper than a standard Salpeter mass function. Solar metallicity Padova isochrone fits to the near-infrared colour-magnitude diagram of NGC 188 resulted in an age of $7.0\pm1.0$ Gyr. The best fit, obtained with the 7.1 Gyr isochrone, produced a distance modulus $\mM=11.1\pm0.1$, $\ebv=0.0$, and a distance to the Sun $\ds=1.66\pm0.08$ kpc. The observed stellar mass (in the range $0.98 \ms - 1.08 \ms$) in NGC 188 is $\mobs=380\pm12 \ms$. A simple extrapolation of the observed overall mass function to stars with $0.08 \ms$ resulted in a total present mass of $\mtot\sim(1.8\pm0.7)\times10^4 \ms$. On the other hand, for a more realistic initial mass function which flattens in the low-mass range, the total mass in NGC 188 drops to $\mtot\sim(3.8\pm1.6)\times10^3 \ms$., Comment: 13pages and 12 figures. Astronomy and Astrophysics, accepted

Published
2005
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53. Proper motion measurements as indicators of binarity in open clusters

Author

Bica, E. and Bonatto, C.

Subjects
Astrophysics
Abstract

We analyze 9 open clusters with ages in the range 70 Myr to 3.2 Gyr using UCAC2 proper motion data and 2MASS photometry. For each cluster we consider the projected velocity distributions in the core and off-core regions separately. In the projected velocity distribution of all sample clusters we find a well-defined low-velocity peak, as well as an excess in the number of stars at larger velocities. The low-velocity peak is accounted for by the random motion of the single stars, while the high-velocity excess can be attributed to the large velocity changes produced by a significant fraction of unresolved binaries in a cluster. We derive kinematic parameters of the single-star distribution, in particular the projected velocity dispersion. The relatively large velocity dispersions derived in this work may reflect the non-virialized state of the clusters. Based on the relative number of high-velocity (binary) and single stars, we inferred for the sample clusters unresolved binary fractions in the range $15%-54%$, for both core and off-core regions. The present results suggest that care must be taken when applying proper-motion filters to sort out members, especially binaries in a star cluster. This paper shows that proper motions turn out to be a useful tool for identifying high-velocity stars as unresolved binary cluster members, and as a consequence, map and quantify the binary component in colour-magnitude diagrams., Comment: 9 pages and 9 figures. Astronomy and Astrophysics, accepted (25/10/2004)

Published
2005
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54. Discovery of three optical open clusters in the Galaxy

Author

Bica, E., Bonatto, C., and Dutra, C. M.

Subjects
Astrophysics
Abstract

We report the discovery of three optical open clusters in the Milky Way. Two clusters are in Scutum (Cluster1 at l=18.44 degrees and b=-0.42 degrees, and Cluster2 at l=19.60 degrees and b=-1.02 degrees), thus projected not far from the Galactic center direction, and the other is in Canis Major (Cluster3 at l=235.61 degrees and b=-4.10 degrees), near the anti-center direction. Cluster3 is less populous than Clusters 1 and 2, but presents evidence of being a physical system. The objects were found optically by inspecting maps obtained from the Guide Star Catalogue and images from the Digitized Sky Survey. No previous identification of cluster has been reported in each area so far. The analysis was carried out with 2MASS photometry in J and H. For Cluster1 we derive an age of 25 Myr, a reddening E(B-V)=2.18 and a distance from the Sun 1.64kpc; for Cluster2, age of 500Myr, E(B-V)=0.91 and distance 2.19kpc; finally for Cluster3, age 32-100Myr, E(B-V)=0.94 and distance of 3.93kpc. Luminosity and mass functions are derived for Clusters1 and 2 which, in turn, allowed us to estimate their observed masses as 147 and 89 solar masses, respectively. Estimated total masses, by extrapolating the mass functions to 0.08 solar mass, amount to 382 and 614 solar masses, for the two clusters. Cluster3 has an observed mass of 55 solar masses. The present results indicate that further searches in the optical might still reveal new open clusters, and more so in infrared bands., Comment: accepted to Astronomy and Astrophysics, 9 figures

Published
2004
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55. Survey of the ISM in Early-Type Galaxies. IV. The Hot Dust Component

Author

Ferrari, F., Pastoriza, M. G., Macchetto, F. D., Bonatto, C., Panagia, N., and Sparks, W. B.

Subjects
Astrophysics
Abstract

We present mid-IR photometric properties for a sample of 28 early-type galaxies observed at 6.75, 9.63 and 15 um with the ISOCAM instrument on board the ISO satellite. We find total mid-IR luminosities in the range 3-48x10^8 L_sun. The spectral energy distribution (SED) of the galaxies were derived using the mid-IR data together with previously published UV, optical and near-IR data. These SEDs clearly show a mid-IR emission coming from dust heated at T ~ 260 K. Dust grains properties are inferred from the mid-IR colors. The masses of the hot dust component are in the range 10-400 M_sun. The relationship between the masses derived from mid-IR observations and those derived from visual extinction are discussed. The possible common heating source for the gas and dust is investigated through the correlations between Ha and mid-IR luminosities., Comment: 10 pages, LaTeX (aa.cls), 11 figures (f. 2-4 are colour plates). Accepted for publication in Astronomy & Astrophysics

Published
2002
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56. Metallicity distribution of bulge globular clusters in M31

Author

Jablonka, P., Bica, E., Bonatto, C., Bridges, T. J., Langlois, M., and Carter, D.

Subjects
Astrophysics
Abstract

This paper presents 3600-5400 Angstroms integrated spectra of 19 globular clusters (or candidates) projected on the central regions of M31, r <=5.3 arcmin (approx 1.2 kpc). We check the cluster nature of these objects, and derive their ages, metallicities and reddenings. From the initial sample, 16 objects turn out to be true star clusters, two are Galactic dwarf stars, and one is a high redshift background galaxy. Only two clusters are found to be super metal rich, suggesting that this phenomenon is not very common. For some clusters, we cannot rule out the possibility that they are of intermediate age; this requires confirmation by observations at the calcium triplet. We also present the metallicity histogram of this central bulge sample and discuss possible scenarios to explain its properties., Comment: Accepted for publication in A&A

Published
1998

60. Data Release 2 of S-PLUS: Accurate template-fitting based photometry covering ∼1000 deg2 in 12 optical filters

Author

Almeida-Fernandes, F, primary, SamPedro, L, additional, Herpich, F R, additional, Molino, A, additional, Barbosa, C E, additional, Buzzo, M L, additional, Overzier, R A, additional, de Lima, E V R, additional, Nakazono, L M I, additional, Oliveira Schwarz, G B, additional, Perottoni, H D, additional, Bolutavicius, G F, additional, Gutiérrez-Soto, L A, additional, Santos-Silva, T, additional, Vitorelli, A Z, additional, Werle, A, additional, Whitten, D D, additional, Costa Duarte, M V, additional, Bom, C R, additional, Coelho, P, additional, Sodré, L, additional, Placco, V M, additional, Teixeira, G S M, additional, Alonso-García, J, additional, Barbosa, C L, additional, Beers, T C, additional, Bonatto, C J, additional, Chies-Santos, A L, additional, Hartmann, E A, additional, Lopes de Oliveira, R, additional, Navarete, F, additional, Kanaan, A, additional, Ribeiro, T, additional, Schoenell, W, additional, and Mendes de Oliveira, C, additional

Published
2022
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61. Canis Major OB1 stellar group contents revealed by Gaia

Author

Santos-Silva, T, primary, Perottoni, H D, additional, Almeida-Fernandes, F, additional, Gregorio-Hetem, J, additional, Jatenco-Pereira, V, additional, Mendes de Oliveira, C, additional, Montmerle, T, additional, Bica, E, additional, Bonatto, C, additional, Monteiro, H, additional, Dias, W S, additional, Barbosa, C E, additional, Fernandes, B, additional, Galli, P A B, additional, Borges Fernandes, M, additional, Kanaan, A, additional, Ribeiro, T, additional, and Schoenell, W, additional

Published
2021
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64. The Southern Photometric Local Universe Survey (S-PLUS): improved SEDs, morphologies, and redshifts with 12 optical filters

Author

Mendes de Oliveira, C, primary, Ribeiro, T, additional, Schoenell, W, additional, Kanaan, A, additional, Overzier, R A, additional, Molino, A, additional, Sampedro, L, additional, Coelho, P, additional, Barbosa, C E, additional, Cortesi, A, additional, Costa-Duarte, M V, additional, Herpich, F R, additional, Hernandez-Jimenez, J A, additional, Placco, V M, additional, Xavier, H S, additional, Abramo, L R, additional, Saito, R K, additional, Chies-Santos, A L, additional, Ederoclite, A, additional, Lopes de Oliveira, R, additional, Gonçalves, D R, additional, Akras, S, additional, Almeida, L A, additional, Almeida-Fernandes, F, additional, Beers, T C, additional, Bonatto, C, additional, Bonoli, S, additional, Cypriano, E S, additional, Vinicius-Lima, E, additional, de Souza, R S, additional, Fabiano de Souza, G, additional, Ferrari, F, additional, Gonçalves, T S, additional, Gonzalez, A H, additional, Gutiérrez-Soto, L A, additional, Hartmann, E A, additional, Jaffe, Y, additional, Kerber, L O, additional, Lima-Dias, C, additional, Lopes, P A A, additional, Menendez-Delmestre, K, additional, Nakazono, L M I, additional, Novais, P M, additional, Ortega-Minakata, R A, additional, Pereira, E S, additional, Perottoni, H D, additional, Queiroz, C, additional, Reis, R R R, additional, Santos, W A, additional, Santos-Silva, T, additional, Santucci, R M, additional, Barbosa, C L, additional, Siffert, Beatriz B, additional, Sodré, L, additional, Torres-Flores, S, additional, Westera, P, additional, Whitten, D D, additional, Alcaniz, J S, additional, Alonso-García, Javier, additional, Alencar, S, additional, Alvarez-Candal, A, additional, Amram, P, additional, Azanha, L, additional, Barbá, R H, additional, Bernardinelli, P H, additional, Borges Fernandes, M, additional, Branco, V, additional, Brito-Silva, D, additional, Buzzo, M L, additional, Caffer, J, additional, Campillay, A, additional, Cano, Z, additional, Carvano, J M, additional, Castejon, M, additional, Cid Fernandes, R, additional, Dantas, M L L, additional, Daflon, S, additional, Damke, G, additional, de la Reza, R, additional, de Melo de Azevedo, L J, additional, De Paula, D F, additional, Diem, K G, additional, Donnerstein, R, additional, Dors, O L, additional, Dupke, R, additional, Eikenberry, S, additional, Escudero, Carlos G, additional, Faifer, Favio R, additional, Farías, H, additional, Fernandes, B, additional, Fernandes, C, additional, Fontes, S, additional, Galarza, A, additional, Hirata, N S T, additional, Katena, L, additional, Gregorio-Hetem, J, additional, Hernández-Fernández, J D, additional, Izzo, L, additional, Jaque Arancibia, M, additional, Jatenco-Pereira, V, additional, Jiménez-Teja, Y, additional, Kann, D A, additional, Krabbe, A C, additional, Labayru, C, additional, Lazzaro, D, additional, Lima Neto, G B, additional, Lopes, Amanda R, additional, Magalhães, R, additional, Makler, M, additional, de Menezes, R, additional, Miralda-Escudé, J, additional, Monteiro-Oliveira, R, additional, Montero-Dorta, A D, additional, Muñoz-Elgueta, N, additional, Nemmen, R S, additional, Nilo Castellón, J L, additional, Oliveira, A S, additional, Ortíz, D, additional, Pattaro, E, additional, Pereira, C B, additional, Quint, B, additional, Riguccini, L, additional, Rocha Pinto, H J, additional, Rodrigues, I, additional, Roig, F, additional, Rossi, S, additional, Saha, Kanak, additional, Santos, R, additional, Schnorr Müller, A, additional, Sesto, Leandro A, additional, Silva, R, additional, Smith Castelli, Analia V, additional, Teixeira, R, additional, Telles, E, additional, Thom de Souza, R C, additional, Thöne, C, additional, Trevisan, M, additional, de Ugarte Postigo, A, additional, Urrutia-Viscarra, F, additional, Veiga, C H, additional, Vika, M, additional, Vitorelli, A Z, additional, Werle, A, additional, Werner, S V, additional, and Zaritsky, D, additional

Published
2019
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65. J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX

Author

Whitten, D. D., primary, Placco, V. M., additional, Beers, T. C., additional, Chies-Santos, A. L., additional, Bonatto, C., additional, Varela, J., additional, Cristóbal-Hornillos, D., additional, Ederoclite, A., additional, Masseron, T., additional, Lee, Y. S., additional, Akras, S., additional, Borges Fernandes, M., additional, Caballero, J. A., additional, Cenarro, A. J., additional, Coelho, P., additional, Costa-Duarte, M. V., additional, Daflon, S., additional, Dupke, R. A., additional, Lopes de Oliveira, R., additional, López-Sanjuan, C., additional, Marín-Franch, A., additional, Mendes de Oliveira, C., additional, Moles, M., additional, Orsi, A. A., additional, Rossi, S., additional, Sodré, L., additional, and Vázquez Ramió, H., additional

Published
2019
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66. J-PLUS: The Javalambre Photometric Local Universe Survey

Author

Cenarro, A. J., primary, Moles, M., additional, Cristóbal-Hornillos, D., additional, Marín-Franch, A., additional, Ederoclite, A., additional, Varela, J., additional, López-Sanjuan, C., additional, Hernández-Monteagudo, C., additional, Angulo, R. E., additional, Vázquez Ramió, H., additional, Viironen, K., additional, Bonoli, S., additional, Orsi, A. A., additional, Hurier, G., additional, San Roman, I., additional, Greisel, N., additional, Vilella-Rojo, G., additional, Díaz-García, L. A., additional, Logroño-García, R., additional, Gurung-López, S., additional, Spinoso, D., additional, Izquierdo-Villalba, D., additional, Aguerri, J. A. L., additional, Allende Prieto, C., additional, Bonatto, C., additional, Carvano, J. M., additional, Chies-Santos, A. L., additional, Daflon, S., additional, Dupke, R. A., additional, Falcón-Barroso, J., additional, Gonçalves, D. R., additional, Jiménez-Teja, Y., additional, Molino, A., additional, Placco, V. M., additional, Solano, E., additional, Whitten, D. D., additional, Abril, J., additional, Antón, J. L., additional, Bello, R., additional, Bielsa de Toledo, S., additional, Castillo-Ramírez, J., additional, Chueca, S., additional, Civera, T., additional, Díaz-Martín, M. C., additional, Domínguez-Martínez, M., additional, Garzarán-Calderaro, J., additional, Hernández-Fuertes, J., additional, Iglesias-Marzoa, R., additional, Iñiguez, C., additional, Jiménez Ruiz, J. M., additional, Kruuse, K., additional, Lamadrid, J. L., additional, Lasso-Cabrera, N., additional, López-Alegre, G., additional, López-Sainz, A., additional, Maícas, N., additional, Moreno-Signes, A., additional, Muniesa, D. J., additional, Rodríguez-Llano, S., additional, Rueda-Teruel, F., additional, Rueda-Teruel, S., additional, Soriano-Laguía, I., additional, Tilve, V., additional, Valdivielso, L., additional, Yanes-Díaz, A., additional, Alcaniz, J. S., additional, Mendes de Oliveira, C., additional, Sodré, L., additional, Coelho, P., additional, Lopes de Oliveira, R., additional, Tamm, A., additional, Xavier, H. S., additional, Abramo, L. R., additional, Akras, S., additional, Alfaro, E. J., additional, Alvarez-Candal, A., additional, Ascaso, B., additional, Beasley, M. A., additional, Beers, T. C., additional, Borges Fernandes, M., additional, Bruzual, G. R., additional, Buzzo, M. L., additional, Carrasco, J. M., additional, Cepa, J., additional, Cortesi, A., additional, Costa-Duarte, M. V., additional, De Prá, M., additional, Favole, G., additional, Galarza, A., additional, Galbany, L., additional, Garcia, K., additional, González Delgado, R. M., additional, González-Serrano, J. I., additional, Gutiérrez-Soto, L. A., additional, Hernandez-Jimenez, J. A., additional, Kanaan, A., additional, Kuncarayakti, H., additional, Landim, R. C. G., additional, Laur, J., additional, Licandro, J., additional, Lima Neto, G. B., additional, Lyman, J. D., additional, Maíz Apellániz, J., additional, Miralda-Escudé, J., additional, Morate, D., additional, Nogueira-Cavalcante, J. P., additional, Novais, P. M., additional, Oncins, M., additional, Oteo, I., additional, Overzier, R. A., additional, Pereira, C. B., additional, Rebassa-Mansergas, A., additional, Reis, R. R. R., additional, Roig, F., additional, Sako, M., additional, Salvador-Rusiñol, N., additional, Sampedro, L., additional, Sánchez-Blázquez, P., additional, Santos, W. A., additional, Schmidtobreick, L., additional, Siffert, B. B., additional, Telles, E., additional, and Vilchez, J. M., additional

Published
2019
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73. Improving distances to Galactic Wolf-Rayet stars

Author

Chené, A. -N, Wyrick, D., Borissova, J., Kuhn, M., Hervé, A., Sebastián Ramírez Alegría, Bonatto, C., Bouret, J. -C, and Kurtev, R.

Subjects
Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, ddc:520, Institut für Physik und Astronomie, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Before GAIA improves the HIPPARCOS survey, direct determination of the distance via parallax is only possible for γ Vel, but the analysis of the cluster or association to which WR stars are associated can give distances with a 50% to a 10% accuracy. The list of Galactic clusters, associations and clusters/association candidates has grown significantly in the last decade with the numerous deep, high resolution surveys of the Milky Way. In this work, we revisit the fundamental parameters of known clusters with WR stars, and we present the search for new ones. All our work is based on the catalogs from the VVV (from the VISTA telescope) and the UKIDS (from the UKIRT telescope) near infrared surveys. Finally, the relations between the fundamental parameters of clusters with WR stars are explored.

Published
2015

75. Massive open star clusters using the VVV survey

Author

Ramírez Alegría, S., primary, Borissova, J., additional, Chené, A.-N., additional, Bonatto, C., additional, Kurtev, R., additional, Amigo, P., additional, Kuhn, M., additional, Gromadzki, M., additional, and Carballo-Bello, J. A., additional

Published
2016
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79. Massive open star clusters using the VVV survey

Author

Chené, A.-N., primary, Ramírez Alegría, S., additional, Borissova, J., additional, O’Leary, E., additional, Martins, F., additional, Hervé, A., additional, Kuhn, M., additional, Kurtev, R., additional, Consuelo Amigo Fuentes, P., additional, Bonatto, C., additional, and Minniti, D., additional

Published
2015
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81. Vvv pointed search for new galactic open clusters

Author

Borissova, J., Radostin Kurtev, Penãloza, F., Bonatto, C., Folkes, S. L., Sale, S. E., Clarke, J., Minniti, D., Catelan, M., Hempel, M., Toledo, I., Saito, R., Ivanov, V., Chene, A. N., Geisler, D., and Bica, E.

Published
2011

91. New galactic star clusters discovered in the VVV survey. Candidates projected on the inner disk and bulge

Author

Borissova, J., primary, Chené, A.-N., additional, Ramírez Alegría, S., additional, Sharma, S., additional, Clarke, J. R. A., additional, Kurtev, R., additional, Negueruela, I., additional, Marco, A., additional, Amigo, P., additional, Minniti, D., additional, Bica, E., additional, Bonatto, C., additional, Catelan, M., additional, Fierro, C., additional, Geisler, D., additional, Gromadzki, M., additional, Hempel, M., additional, Hanson, M. M., additional, Ivanov, V. D., additional, Lucas, P., additional, Majaess, D., additional, Moni Bidin, C., additional, Popescu, B., additional, and Saito, R. K., additional

Published
2014
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95. Massive open star clusters using the VVV survey

Author

Ramírez Alegría, S., primary, Borissova, J., additional, Chené, A. N., additional, O’Leary, E., additional, Amigo, P., additional, Minniti, D., additional, Saito, R. K., additional, Geisler, D., additional, Kurtev, R., additional, Hempel, M., additional, Gromadzki, M., additional, Clarke, J. R. A., additional, Negueruela, I., additional, Marco, A., additional, Fierro, C., additional, Bonatto, C., additional, and Catelan, M., additional

Published
2014
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96. Investigating potential planetary nebula/cluster pairs

Author

Moni Bidin, C., primary, Majaess, D., additional, Bonatto, C., additional, Mauro, F., additional, Turner, D., additional, Geisler, D., additional, Chené, A.-N., additional, Gormaz-Matamala, A. C., additional, Borissova, J., additional, Kurtev, R. G., additional, Minniti, D., additional, Carraro, G., additional, and Gieren, W., additional

Published
2014
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97. Anchors for the cosmic distance scale: the Cepheids U Sagittarii, CF Cassiopeiae, and CEab Cassiopeiae

Author

Majaess, D., primary, Carraro, G., additional, Moni Bidin, C., additional, Bonatto, C., additional, Berdnikov, L., additional, Balam, D., additional, Moyano, M., additional, Gallo, L., additional, Turner, D., additional, Lane, D., additional, Gieren, W., additional, Borissova, J., additional, Kovtyukh, V., additional, and Beletsky, Y., additional

Published
2013
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