Excesos IR

F

Discos “flared”

•Radiation enters at angle to local normal: deposits at o ~1, o= cos o,,, , o, , 0 << 1

(*) > (disk), because dust opacity decreases with => * > disk => energy is deposited at disk = 0 /q, with q = */disk >> 1

•Stellar energy is deposited in upper levels

Upper layers are hotter than regions where the continuum form

N

Continuum disk ~ 1

disk =0/q << 10

Dust absorption/emission different

* d

Dust opacity

abs emiss

star + shockdisk

Properties of disk structure

D’Alessio et al 1999

zs

1/R

“flared” hasta R ~ 100 AU

Tc

Tfot

Tvis

T0

Tc ~ Tfot 1/R1/2

Tc > Tfot

T profiles

T0

TfotTc

Disk optical depth

SEDs

D’Alessio et al 1999

SED @ IR similar for low dM/dt – dominated by irradiationFmm increases with dM/dt /

Dependence of SED on inclination to line of sight

D’Alessio et al 1999

At high inclinations disk self-absorbs

scattered light

inclination

Imagenes

D’Alessio et al 1999

Dark lane: optically thick disk layers near mid-plane

Optical/mm

Optical/nearIR scattered light (upper layers)

mm emission(midplane, most mass)

Gas T different from dust T

Glassgold et al 2004

X-ray heating of gas in upper less dense layers