J-PLUS: Detecting and studying extragalactic globular clusters

The case of NGC 1023^★

¹ Núcleo de Astronomía, Universidad Diego Portales, Ejército 441, Santiago, Chile
e-mail: danielle.debrito@mail.udp.cl
² Universidade de São Paulo, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, R. do Matão 1226, São Paulo, SP 05508-090, Brazil
³ Observatório do Valongo, Universidade Federal do Rio de Janeiro, Ladeira do Pedro Antônio 43, Rio de Janeiro, RJ 20080-090, Brazil
⁴ Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Morelia, Michoacán 58089, Mexico
⁵ Centro de Investigaciones de Astronomía (CIDA), Mérida 5101, Venezuela
⁶ Instituto de Física, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Porto Alegre, R.S. 90040-060, Brazil
⁷ Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, PR China
⁸ Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, São José dos Campos, SP 12244-000, Brazil
⁹ Centro de Estudios de Física del Cosmos de Aragón, Unidad Asociada al CSIC, Plaza San Juan 1, 44001 Teruel, Spain
¹⁰ Centre for Astrophysics & Supercomputing, Swinburne University, Hawthorn VIC 3122, Australia
¹¹ Instituto de Astrofísica de Andalucía – CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain
¹² Instituto de Astrofísica de Canarias, Calle Vía Láctea SN, ES38205 La Laguna, Spain
¹³ Departamento de Astrofísica, Universidad de La Laguna, ES38205 La Laguna, Spain
¹⁴ Observatório Nacional – MCTI (ON), Rua Gal. José Cristino 77, São Cristóvão, 20921-400 Rio de Janeiro, Brazil
¹⁵ Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain

Received: 8 October 2021
Accepted: 6 May 2022

Abstract

Context. Extragalactic globular clusters (GCs) are key objects in studies of galactic histories. The advent of wide-field surveys, such as the Javalambre Photometric Local Universe Survey (J-PLUS), offers new possibilities for the study of these systems.

Aims. We performed the first study of GCs in J-PLUS to recover information on the history of NGC 1023, taking advantage of wide-field images and 12 filters.

Methods. We developed the semiautomatic pipeline GCFinder for detecting GC candidates in J-PLUS images, which can also be adapted to similar surveys. We studied the stellar population properties of a sub-sample of GC candidates using spectral energy distribution (SED) fitting.

Results. We found 523 GC candidates in NGC 1023, about 300 of which are new. We identified subpopulations of GC candidates, where age and metallicity distributions have multiple peaks. By comparing our results with the simulations, we report a possible broad age-metallicity relation, supporting the notion that NGC 1023 has experienced accretion events in the past. With a dominating age peak at 10¹⁰ yr, we report a correlation between masses and ages that suggests that massive GC candidates are more likely to survive the turbulent history of the host galaxy. Modeling the light of NGC 1023, we find two spiral-like arms and detect a displacement of the galaxy’s photometric center with respect to the outer isophotes and center of GC distribution (~700pc and ~1600pc, respectively), which could be the result of ongoing interactions between NGC 1023 and NGC 1023A.

Conclusions. By studying the GC system of NGC 1023 with J-PLUS, we showcase the power of multi-band surveys for these kinds of studies and we find evidence to support the complex accretion history of the host galaxy.