Disks Around Young Stars with ALMA & SPHEREx Catherine Espaillat Boston University

Disks Around Young Stars with ALMA & SPHEREx Submm/mm observatories provide information on the distribution of gas and (large) dust grains in the disk. SPHEREx can provide complementary information on the innermost disk by measuring the location, curvature, and height of the inner rim detecting changes in the inner rim with time

Our current sketch of a protoplanetary disk Henning & Semenov 2014

Spatial distribution of dust grains varies with wavelength TW Hya Andrews et al. 2012, 2015

also AB Aur (Pietu et al. 2005), TW Hya (Hughes et al. 2007), Several disk cavities now confirmed via submm interferometric imaging also AB Aur (Pietu et al. 2005), TW Hya (Hughes et al. 2007), SAO 206462 (Brown et al. 2009), RY Tau (Isella et al. 2010a), DM Tau (Andrews et al. 2011), IRS 48 (Brown et al. 2012), HD 142527 (Casassus et al. 2013), Sz 91 (Tsukagoshi et al. 2014) Figure from Espaillat et al. 2014, PPVI; Data from Mathews et al. 2012 Isella, et al. 2010, Brown et al. 2009, Andrews et al. 2009, Hughes et al. 2009, Andrews et al. 2011b, Brown, et al. 2008, Cieza et al. 2012, Rosenfeld et al. 2013, Andrews et al. 2010

Gas seen within dust cavities with ALMA van der Marel et al. 2015

Striking small-scale disk structure revealed by ALMA ALMA Partnership 2015

Disks Around Young Stars with ALMA & SPHEREx Submm/mm observatories provide information on the distribution of gas and (large) dust grains in the disk. SPHEREx can provide complementary information on the innermost disk by measuring the location, curvature, and height of the inner rim detecting changes in the inner rim with time

NIR excess emission can be used to measure location of inner disk rim Twall=1400K Twall=1300K Twall=1200K Twall=1000K Twall=1400K Muzerolle et al. 2003 Espaillat et al. 2008

NIR excess emission can be used to measure shape & height of inner disk rim Millan-Gabet et al. 2016

SPHEREx will provide spectra for every known, nearby YSO 6 arcsec at ~140 pc is ~800 AU Typical disk is ~600 AU in diameter SPHEREx will provide spectra for at least 600 disks Ribas et al. 2014

Disks Around Young Stars with ALMA & SPHEREx Submm/mm observatories provide information on the distribution of gas and (large) dust grains in the disk. SPHEREx can provide complementary information on the innermost disk by measuring the location, curvature, and height of the inner rim detecting changes in the inner rim with time

Spitzer IRAC [3.6] and [4.5] YSO Variability Surveys: Young stellar objects are highly variable Spitzer IRAC [3.6] and [4.5] YSO Variability Surveys: Orion Nebula Cluster – YSOVAR (Morales-Calderon et al. 2011) 2000 objects observed 81 times over 40 days IC 348 (Flaherty et al. 2013) 200 objects observed 38 times over 40 days IR variability of typically 0.15-0.3 mag seen in ~80% of embedded disk systems, 60-70% of disk systems, and 20-45% of diskless stars.

broken line: model with shorter inner rim Evidence for changes in inner disk rim height via variable “see-saw” IR emission UX Tau A broken line: model with shorter inner rim Espaillat et al. 2011; also Muzerolle et al. 2010, Flaherty et al. 2012

Potential causes of changes in inner disk rim height Planet-disk interaction Ogilvie & Lubow 2002 Flaherty et al. 2011 Turbulence from MRI Warped inner disk Hirose & Turner 2011 Flaherty et al. 2011

Disks Around Young Stars with ALMA & SPHEREx Submm/mm observatories provide information on the distribution of gas and (large) dust grains in the disk. SPHEREx can provide complementary information on the innermost disk by measuring the location, curvature, and height of the inner rim detecting changes in the inner rim with time

FUV-NIR variability in disks around young stars GM Aur FUV NUV Optical NIR Ingleby, Espaillat et al. 2015