Calendar

Feb
22
Thu
Riunione CME
Feb 22 @ 11:30 – 13:00
Riunione Julien
Feb 22 @ 15:00 – 16:30
Feb
23
Fri
Riunione MINERVA
Feb 23 @ 9:30 – 18:00
Feb
26
Mon
lezione dottorato (corso di management)
Feb 26 @ 14:00 – 16:00
Feb
27
Tue
Riunione EXOPA
Feb 27 @ 10:00 – 13:00
Seminario: Victor Almendros (INAF)
Feb 27 @ 15:00 – 16:30

Speaker: Victor Almendros (INAF)

Title: Evolution of the mass accretion rate and its relationship with the stellar and disk mass from brown dwarfs to stars

Abstract:
The time evolution of the dependence of the mass accretion rate with the stellar mass and the disk mass represents a fundamental way to understand the evolution of protoplanetary disks and the formation of planets. Recent studies suggest the existence of a bimodal accretion behavior at 2-3 Myr in the relationship of the stellar mass and the mass accretion rate, which may indicate that low-mass stars evolve faster (than higher-mass stars) into lower accretion rates. We recently measured the mass accretion rate of 26 new brown dwarfs and low-mass stars in the Ophiuchus, Cha-I and Upper Scorpius star-forming regions using X-Shooter/VLT. Combining these new observations with data from the literature, we compared the relations between accretion rate and stellar/disk properties of four different star-forming regions with different ages: Ophiuchus (1 Mar), Lupus (2 Myr), Cha-I (3 Myr) and Upper Scorpius (5-12 Myr). Overall, we observe hints of a faster evolution into low accretion rates of low-mass stars and brown dwarfs. At the same time, we also found that brown dwarfs present larger Mdisk/Macc ratios than stars in Ophiuchus, Lupus and Cha-I. This apparently contradictory result may imply that the evolution of protoplanetary disks around brown dwarfs may be different than in the stellar regime.

Feb
28
Wed
lezione dottorato (corso di management)
Feb 28 @ 14:00 – 16:00
Mar
4
Mon
lezione dottorato (corso di management)
Mar 4 @ 14:00 – 16:00
Mar
6
Wed
lezione dottorato (corso di management)
Mar 6 @ 14:00 – 16:00
Mar
11
Mon
lezione dottorato (corso di management)
Mar 11 @ 14:00 – 16:00