Infrared observations of the flaring maser source G358.93-0.03: SOFIA confirms an accretion burst from a massive young stellar object
| Autor: | Mark Gurwell, Hendrik Linz, J.L. Van der Walt, Claudia Cyganowski, C. Fischer, A. E. Volvach, Gabriele Surcis, Ross A. Burns, Andrej M. Sobolev, V. Wolf, J. Eislöffel, Sylvio Klose, O. Bayandina, Bringfried Stecklum, Crystal L. Brogan, Koichiro Sugiyama, A. Caratti o Garatti, G. C. MacLeod, Gabor Orosz, Yoshinori Yonekura, Kee-Tae Kim, S. Schmidl, Naomi Hirano, Karl M. Menten, M. Olech, Todd R. Hunter, T. K. Sridharan |
|---|---|
| Přispěvatelé: | ITA, USA, GBR, DEU, CAN, TWN, KOR, JPN, IRL, NLD, POL, CHN, ZAF, RUS, University of St Andrews. School of Physics and Astronomy |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
GAMMA RAYS
SPECTROMETERS Young stellar object DUST Astrophysics RADIATIVE TRANSFER ENVIRONMENTAL CHARACTERISTIC 01 natural sciences INTERFEROMETRIC IMAGING RADIATIVE TRANSFER MODEL law.invention Luminosity law QB Astronomy Astrophysics::Solar and Stellar Astrophysics Maser FIR FILTERS 010303 astronomy & astrophysics QC QB Physics SPECTROSCOPY 3rd-DAS ATACAMA LARGE MILLIMETER/SUB-MILLIMETER ARRAYS FIELD-IMAGING FAR-INFRARED LINE SPECTROMETERS LUMINANCE Astrophysics - Solar and Stellar Astrophysics SPECTRAL ENERGY DISTRIBUTION Spectral energy distribution METHANOL Astrophysics::Earth and Planetary Astrophysics Flare ACCRETION ACCRETION DISKS INFRARED DEVICES INDIVIDUAL: G358.93-0.03 [STARS] Astrophysics::High Energy Astrophysical Phenomena MASERS FOS: Physical sciences Context (language use) Astrophysics::Cosmology and Extragalactic Astrophysics Submillimeter Array indvididual objects (G358.93-0.03) [Stars] FORMATION [STARS] 0103 physical sciences INTEGRAL FIELD SPECTROSCOPY Solar and Stellar Astrophysics (astro-ph.SR) Astrophysics::Galaxy Astrophysics PROTOSTARS [STARS] STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMIES 010308 nuclear & particles physics Astronomy and Astrophysics GIANT STARS Accretion (astrophysics) QC Physics 13. Climate action Space and Planetary Science |
| Zdroj: | Astron. Astrophys. Astronomy and Astrophysics |
| Popis: | Class II methanol masers are signs of massive young stellar objects (MYSOs). Recent findings show that MYSO accretion bursts cause flares of these masers. Thus, maser monitoring can be used to identify such bursts. Burst-induced SED changes provide valuable information on a very intense phase of high-mass star formation. In mid-January 2019, a maser flare of the MYSO G358.93-0.03 was reported. ALMA and SMA imaging resolved the core of the star forming region and proved the association of the masers with the brightest continuum source MM1. However, no significant flux rise of the (sub)mm dust continuum was found. Thus, we performed NIR imaging with GROND and IFU spectroscopy with FIFI-LS aboard SOFIA to detect possible counterparts to the (sub)mm sources, and compare their photometry to archival measurements. The comparison of pre-burst and burst SEDs is of crucial importance to judge whether a luminosity increase due to the burst is present and if it triggered the maser flare. The FIR fluxes of MM1 measured with FIFI-LS exceed those from Herschel significantly, which clearly confirms the presence of an accretion burst. The second epoch data, taken about 16 months later, still show increased fluxes. Our RT modeling yielded major burst parameters and suggests that the MYSO features a circumstellar disk which might be transient. From the multi-epoch SEDs, conclusions on heating and cooling time-scales could be drawn. Circumstances of the burst-induced maser relocation have been explored. The verification of the accretion burst from G358 is another confirmation that Class II methanol maser flares represent an alert for such events. The few events known to date already indicate that there is a broad range in burst strength and duration as well as environmental characteristics. The G358 event is the shortest and least luminous MYSO accretion burst so far. Comment: 22 pages, 11 figures, accepted by A&A. Abstract abridged for arxiv submission |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|