Repositório Digital

A- A A+

FSR 1716 : a new Milky Way globular cluster confirmed using VVV RR Lyrae stars

.

FSR 1716 : a new Milky Way globular cluster confirmed using VVV RR Lyrae stars

Mostrar registro completo

Estatísticas

Título FSR 1716 : a new Milky Way globular cluster confirmed using VVV RR Lyrae stars
Autor Minniti, Dante
Palma, Tali
Dékány, István
Hempel, Maren
Rejkuba, Marina
Pullen, Joyce
Alonso Garcia, Javier
Barbá, Rodolfo H.
Barbuy, Beatriz
Bica, Eduardo Luiz Damiani
Bonatto, Charles Jose
Borissova, Jura
Catelan, Márcio
Carballo-Bello, Julio A.
Chené, André-Nicolas
Claria Olmedo, Juan Jose
Cohen, Roger
Contreras Ramos, Rodrigo
Dias, Bruno Moreira de Souza
Emerson, Jim P.
Froebrich, Dirk
Buckner, Anne S. M.
Geisler, Doug
Gonzalez, Oscar A.
Gran, Felipe
Hajdu, Gergely
Irwin, Michael John
Ivanov, Valentin D.
Kurtev, Radostin Georgiev
Lucas, Philip W.
Majaess, Daniel J.
Mauro, Francesco
Moni Bidin, Christian
Navarrete, Camila
Ramírez Alegría, Sebastián
Saito, Roberto K.
Valenti, Elena
Zoccali, Manuela
Abstract We use deep multi-epoch near-IR images of the VISTA Variables in the Vía Láctea (VVV) Survey to search for RR Lyrae stars toward the Southern Galactic plane. Here, we report the discovery of a group of RR Lyrae stars close together in VVV tile d025. Inspection of the VVV images and PSF photometry reveals that most of these stars are likely to belong to a globular cluster that matches the position of the previously known star cluster FSR 1716. The stellar density map of the field yields a >100σ detection for this candidate globular cluster that is centered at equatorial coordinates R.A.J2000 = 16:10:30.0, decl.J2000 = −53:44:56 and galactic coordinates l = 329.77812, b = −1.59227. The color–magnitude diagram of this object reveals a well-populated red giant branch, with a prominent red clump at Ks = 13.35±0.05, and J−Ks = 1.30±0.05. We present the cluster RR Lyrae positions, magnitudes, colors, periods, and amplitudes. The presence of RR Lyrae indicates an old globular cluster, with an age >10 Gyr. We classify this object as an Oosterhoff type I globular cluster, based on the mean period of its RR Lyrae type ab, áPñ = 0.540 days, and argue that this is a relatively metal-poor cluster with [Fe/H] = −1.5±0.4 dex. The mean extinction and reddening for this cluster are AKs = 0.38 0.02 and E( J−Ks) = 0.72±0.02 mag, respectively, as measured from the RR Lyrae colors and the near-IR color– magnitude diagram. We also measure the cluster distance using the RR Lyrae type ab stars. The cluster mean distance modulus is (m−M)0 = 14.38±0.03 mag, implying a distance D = 7.5±0.2 kpc and a Galactocentric distance RG = 4.3 kpc.
Contido em The astrophysical journal. Bristol. Vol. 838, no. 1 (Mar. 2017), L14, 7 p.
Assunto Aglomerados globulares
Fotometria estelar
Galáxias
[en] Galaxies: photometry
[en] Globular clusters: general
[en] Stars: variables: RR Lyrae
Origem Estrangeiro
Tipo Artigo de periódico
URI http://hdl.handle.net/10183/169045
Arquivos Descrição Formato
001026294.pdf (1.368Mb) Texto completo (inglês) Adobe PDF Visualizar/abrir

Este item está licenciado na Creative Commons License

Este item aparece na(s) seguinte(s) coleção(ões)


Mostrar registro completo

Percorrer



  • O autor é titular dos direitos autorais dos documentos disponíveis neste repositório e é vedada, nos termos da lei, a comercialização de qualquer espécie sem sua autorização prévia.
    Projeto gráfico elaborado pelo Caixola - Clube de Criação Fabico/UFRGS Powered by DSpace software, Version 1.8.1.