Jets, Disks, and Cavities: The Protoplanetary Zoo in 2006

C. Grady

Coronagraphic Imaging Surveys

• On-going effort to obtain coronagraphic imagery with supporting narrow-band coronagraphic imagery (GFP), FUV spectra (FUSE, HST), x-ray data (Chandra)

• Goal is to understand, for more isolated systesm at what point central clearing is remotely detectable.

Jets and Accretion

• Now have 6, optically visible Herbig Ae stars with jets or HH knots

• Detection fraction is similar to T Tauri stars

• Age range spans 0.7-7 Myr

• None seen in the ZAMS objects

Disks with Central Dust Deficits• 4 Herbig Ae Stars• 4 T Tauri stars• Herbig Ae stars include one object with comet-

like dust (HD 100546), and 3 lacking warm silicate emission.

• HD 100546 has no jet, and possesses an eccentric 13 AU radius cavity. Is this typical?

• The 4 stars have been modelled as ZAMS objects, but a potentially related one (HD 141569 A) is more correctly a factor of 2 (5 Myr) younger. Is this typical?

HD 169142• A5Ve star (in the optical),

A8Ve (in the UV) at d=145 pc

• Abundant mm dust emission, with disk imaged to 1.6” (230 AU; Dent et al. 2005; Raman et al. 2006)

• 13° inclination (Raman et al. 2006)

• v sin i=55 (Dunkin et al. 1997), implying that veq=240 km/s - later A-type analog of Vega (Aufdenberg 2005)

Disk in NIR Scattered Light

• Disk is azimuthally symmetric• NICMOS traces disk to 1.3”• Radial surface brightness goes as r-3 , implying

r-1.

HD 169142 Visit 1 HD 169142 Visit 2 PSF-PSF

The Environment

• Unlike HD 100546, HD 169142 has an object 8” SW of the Herbig Ae star with NIR colors appropriate for an M Star.

• Object is an H emitter (GFP data).

HD 169142B

• Companion is common proper motion since 1980s, and is M2.5Ve.

Age Estimate

• Companion is double as seen by HST.

• Using F110W magnitudes, d=145 pc, and Teff from the optical spectra, we can locate the brighter star in the HR diagram: coeval with HR 4796 A, at about 8± 4 Myr.

Conclusions and Speculations• All 4 stars (HD 100546, HD 135344, HD 139614, and HD

169142) have veq>200 km/s.• Two of the 4 (HD 135344, Thi et al. 2001; HD 169142, this

study) have estimated ages in the 8-16 Myr range. The other 2 are ZAMS from their location in the HR diagram.

• Central clearing in these systems seems to be a process which occurs comparatively late in the history of the disk. For HD 100546 a second body is implicated (Grady et al. 2005) , despite the underabundance of iron and siderophiles in both the star and the infalling material (Grady et al. 1997).

• May have stumbled onto a population of planetary systems with architechtures which differ from the bulk of the extra-solar systems. Astrometric follow-up is needed (SIM), as is higher angular resolution imagery.