Un'illustrazione qualitativa che mostra l'emissione aurorale irradiata sulla shell star J0508-21, supponendo che la stella abbia un campo magnetico stellare multipolare e che l'emissione radio sia innescata da una possibile interazione magnetica con un pianeta approssimativamente in rotazione e in evaporazione che è potenzialmente anche responsabile di minimi nelle curve di luce della stella stessa, Kaur et al. 2024b
Simranpreet Kaur
Giovedì 5 Dicembre 2024, H 11.00 AM – Aula seminari Villa Magliolia- INAF-OATo
LIVE STREAMING
Abstract
Radio stars are rare, though a few recent studies, based on the cross-matching of different catalogs, are extending the known samples for M dwarfs especially.
The talk will present new findings on the radio emission characteristics of two distinct classes of young stars: the scallop-shell star 2MASS J05082729−2101444 (J0508-21) and the young stellar object [BHB2007]-1.
Both systems exhibit variable circularly polarized radio emission, a hallmark of magnetically influenced plasma processes, shedding light on their magnetic field geometries and underlying emission mechanisms.
J0508-21 shows millijansky-level emission at 575–720 MHz with 20–50% circular polarization and periodic helicity reversals, suggesting a mix of persistent gyro-synchrotron emission and highly polarized auroral bursts, indicative of electron cyclotron maser processes.
On the other hand, for [BHB2007]-1, VLA data at 15 GHz has revealed 15–20% circular polarization linked to magnetic fields, alongside unpolarized emission likely caused by jet-induced shocks.
However, in both the cases, the results reveal diverse magnetic phenomena in young stars and underscore the need for coordinated multiwavelength studies to further understand their origins.
Referente locale: Mario Dammasso
