| Texto completo | |
| Autor(es): |
Navarete, Felipe
;
dos Santos, Pedro Ticiani
;
Carciofi, Alex Cavalieri
;
Figueiredo, Andre Luiz
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ASTROPHYSICAL JOURNAL; v. 970, n. 2, p. 20-pg., 2024-08-01. |
| Resumo | |
H alpha emission is a clear indicator of circumstellar activity in Be stars, historically employed to assess the classical Be star (CBe) population in young open clusters (YOCs). The YOC NGC 330 in the Small Magellanic Cloud exhibits a large known fraction of CBe stars and was selected for a pilot study to establish a comprehensive methodology for identifying H alpha emitters in the Magellanic Clouds, encompassing the entire B-type spectral range. Using the SOAR Adaptive Module Imager (SAMI), we investigated the stellar population of NGC 330 using multiband BVRI+H alpha imaging. We identified H alpha emitters within the entire V-band range covered by SAMI/SOAR observations (V less than or similar to 22), comprising the complete B-type stellar population and offering a unique opportunity to explore the Be phenomenon across all spectral subclasses. The stellar radial distribution shows a clear bimodal pattern between the most massive (B5 or earlier) and the lower mass main-sequence objects (later than B6) within the cluster. The former is concentrated toward the cluster center (showing a dispersion of sigma = 4.26 +/- 0.20 pc), whereas the latter extends across larger radii (sigma = 10.83 +/- 0.65 pc), indicating mass stratification within NGC 330. The total fraction of emitters is 4.4% +/- 0.5%, notably smaller than previous estimates from flux- or seeing-limited observations. However, a higher fraction of H alpha emitters is observed among higher mass stars (32.8% +/- 3.4%) than within lower mass (4.4% +/- 0.9%). Consequently, the putative CBe population exhibits distinct dynamical characteristics compared to the bulk of the stellar population in NGC 330. These findings highlight the significance of the current observations in providing a complete picture of the CBe population in NGC 330. (AU) | |
| Processo FAPESP: | 18/04055-8 - Espectroscopia de alta precisão: das primeiras estrelas aos planetas |
| Beneficiário: | Jorge Luis Melendez Moreno |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 23/06539-0 - Verificação de qualidade de imagem, calibração de dados e treinamento no manuseio de banco de dados |
| Beneficiário: | Andre Luiz Figueiredo |
| Modalidade de apoio: | Bolsas no Brasil - Programa Capacitação - Treinamento Técnico |
| Processo FAPESP: | 09/54006-4 - Um cluster de computadores para o Departamento de Astronomia do IAG-USP e para o Núcleo de Astrofísica da UNICSUL |
| Beneficiário: | Elisabete Maria de Gouveia Dal Pino |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |
| Processo FAPESP: | 19/13354-1 - Discos de decréscimo e outflows em torno de estrelas em rápida rotação |
| Beneficiário: | Alex Cavaliéri Carciofi |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |