E-viri
Recenzirano
-
Homan, Ward; Montargès, Miguel; Pimpanuwat, Bannawit; Richards, Anita M. S.; Wallström, Sofia H. J.; Kervella, Pierre; Decin, Leen; Zijlstra, Albert; Danilovich, Taissa; de Koter, Alex; Menten, Karl; Sahai, Raghvendra; Plane, John; Lee, Kelvin; Waters, Rens; Baudry, Alain; Tat Wong, Ka; Millar, Tom J.; Van de Sande, Marie; Lagadec, Eric; Gobrecht, David; Yates, Jeremy; Price, Daniel; Cannon, Emily; Bolte, Jan; De Ceuster, Frederik; Herpin, Fabrice; Nuth, Joe; Philip Sindel, Jan; Kee, Dylan; Grey, Malcolm D.; Etoka, Sandra; Jeste, Manali; Gottlieb, Carl A.; Gottlieb, Elaine; McDonald, Iain; El Mellah, Ileyk; Müller, Holger S. P.
Astronomy and astrophysics (Berlin), 12/2020, Letnik: 644Journal Article
The nebular circumstellar environments of cool evolved stars are known to harbour a rich morphological complexity of gaseous structures on different length scales. A large part of these density structures are thought to be brought about by the interaction of the stellar wind with a close companion. The S-type asymptotic giant branch (AGB) star π 1 Gruis, which has a known companion at ∼440 au and is thought to harbour a second, closer-by (< 10 au) companion, was observed with the Atacama Large Millimeter/submillimeter Array as part of the A TOMIUM Large programme. In this work, the brightest CO, SiO, and HCN molecular line transitions are analysed. The continuum map shows two maxima, separated by 0.04″ (6 au). The CO data unambiguously reveal that π 1 Gru’s circumstellar environment harbours an inclined, radially outflowing, equatorial density enhancement. It contains a spiral structure at an angle of ∼38 ± 3° with the line-of-sight. The HCN emission in the inner wind reveals a clockwise spiral, with a dynamical crossing time of the spiral arms consistent with a companion at a distance of 0.04″ from the AGB star, which is in agreement with the position of the secondary continuum peak. The inner wind dynamics imply a large acceleration region, consistent with a beta-law power of ∼6. The CO emission suggests that the spiral is approximately Archimedean within 5″, beyond which this trend breaks down as the succession of the spiral arms becomes less periodic. The SiO emission at scales smaller than 0.5″ exhibits signatures of gas in rotation, which is found to fit the expected behaviour of gas in the wind-companion interaction zone. An investigation of SiO maser emission reveals what could be a stream of gas accelerating from the surface of the AGB star to the companion. Using these dynamics, we have tentatively derived an upper limit on the companion mass to be ∼1.1 M ⊙ .
Avtor
Vnos na polico
Trajna povezava
- URL:
Faktor vpliva
Dostop do baze podatkov JCR je dovoljen samo uporabnikom iz Slovenije. Vaš trenutni IP-naslov ni na seznamu dovoljenih za dostop, zato je potrebna avtentikacija z ustreznim računom AAI.
Leto | Faktor vpliva | Izdaja | Kategorija | Razvrstitev | ||||
---|---|---|---|---|---|---|---|---|
JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP |
Baze podatkov, v katerih je revija indeksirana
Ime baze podatkov | Področje | Leto |
---|
Povezave do osebnih bibliografij avtorjev | Povezave do podatkov o raziskovalcih v sistemu SICRIS |
---|
Vir: Osebne bibliografije
in: SICRIS
To gradivo vam je dostopno v celotnem besedilu. Če kljub temu želite naročiti gradivo, kliknite gumb Nadaljuj.