The enigma of Gaia18cjb
- Autor(en)
- Eleonora Fiorellino, Péter Ábrahám, Ágnes Kóspál, Mária Kun, Juan M. Alcalá, Alessio Caratti O Garatti, Fernando Cruz-Sáenz De Miera, David García-Álvarez, Teresa Giannini, Sunkyung Park, Michal Siwak, Máté Szilágyi, Elvira Covino, Gabor Marton, Zsófia Nagy, Brunella Nisini, Zsófia Marianna Szabó, Zsófia Bora, Borbála Cseh, Csilla Kalup, Máte Krezinger, Levente Kriskovics, Waldemar Ogloza, András Pál, Ádám Sódor, Eda Sonbas, Róbert Szakáts, Krisztián Vida, József Vinkó, Lukasz Wyrzykowski, Pawel Zielinski
- Abstrakt
Context. Gaia18cjb is one of the Gaia-alerted eruptive young star candidates that has been experiencing a slow and strong brightening during the last 13 years, similarly to some FU Orionis-type objects. Aims. The aim of this work is to derive the young stellar nature of Gaia18cjb and determine its physical and accretion properties to classify its variability. Methods. We conducted monitoring observations using multi-filter optical and near-infrared (NIR) photometry, as well as NIR spectroscopy. We present an analysis of pre-outburst and outburst optical and IR light curves, color-magnitude diagrams in different bands, the detection of NIR spectral lines, and estimates of both stellar and accretion parameters during the burst. Results. The optical light curve shows an unusually long (over 8 years) brightening event of 5 mag in the last 13 years, before reaching a plateau indicating that the burst is still ongoing, suggesting a FU Orionis-like (FUor-like) nature. The same outburst is less strong in the IR light curves. The NIR spectra, obtained during the outburst, exhibit emission lines typical of highly accreting low-intermediate mass young stars with typical EX Lupi-type (EXor) features. The spectral index of Gaia18cjb SED classifies it as a Class I in the pre-burst stage and a flat-spectrum young stellar object (YSO) during the burst. Conclusions. Gaia18cjb is an eruptive YSO that exhibits FUor-like photometric features (in terms of brightening amplitude and length of the burst) as well as EXor-like spectroscopic features and accretion rate. Its nature appears similar to that of V350 Cep and V1647 Ori, which have been classified as objects in between FUors and EXors.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- INAF-Osservatorio Astronomico di Capodimonte, MTA Társadalomtudományi Kutatóközpont, Magyar Tudományos Akadémia, Eötvös Loránd University Budapest, Max-Planck-Institut für Astronomie, Université de Toulouse, Instituto de Astrofísica de Canarias (IAC), INAF - Osservatorio Astronomico di Roma, Max-Planck-Institut für Radioastronomie, University of St. Andrews, Pedagogical University of Cracow, Adiyaman University, University of Warsaw, Nicolaus Copernicus University
- Journal
- Astronomy and Astrophysics
- Band
- 686
- Anzahl der Seiten
- 19
- ISSN
- 0004-6361
- DOI
- https://doi.org/10.1051/0004-6361/202347777
- Publikationsdatum
- 06-2024
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Schlagwörter
- ASJC Scopus Sachgebiete
- Astronomy and Astrophysics, Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/0384babd-0e7b-46f4-b55f-4d110503ae92