For a listing of my published works, click the ADS link above

Recent Papers

Morphologies of protostellar outflows: An ALMA view

Peters, T., Klaassen, P.D., et al. (Accepted by MNRAS astro-ph/1310.7356)

We present synthetic ALMA observations of protostellar outflows based on numerical magnetohydrodynamic collapse simulations. We find significant velocity gradients in our outflow models and a very prominent helical structure within the outflows.

The Ionization Driven Molecular Outflow from K3-50A

Klaassen et al., 2013, A&A 557 A107

We show that there is a small scale molecular outflow at the center of this high mass star forming region, and that it is powered by the previously detected ionized outflow (Depree et al. 1994)

ALMA detection of the rotating molecular disk wind from the young star HD 163296

Klaassen et al., 2013 Astronomy and Astrophysics, 555, 73

There's a disk wind coming from this source, but it has not been detected before, because previous observations have not been sensitive enough. The disk wind from this source is extended along the same position angle as the HH knot complex (HH 409), and has a double corkscrew morphology.

The One Ring: Resolving the CO snowline around HD163296 with ALMA

Mathews, Klaassen, et al., 2013 A&A 557 A132

DCO+ can be enhanced at the CO snowline. The ALMA Science Verification data of HCO+ and isotopologues presented here shows an abundance enhancement of DCO+ at the CO snow line. This resolved DCO+ emission shows a ring morphology, centered at approximately 150 AU, the distance from the star where the midplane tempeature first drops to 19 K.

Unveiling the gas and dust disk structure in HD163296 using ALMA observations

de Gregorio-Monsalvo et al., 2013 A&A 557 A133

The high sensitivity and resolution already obtainable with ALMA data shows the vertical structure of the CO J=3-2 emission in HD 163296. We have modelled the CO J=3-2 emission, and show that models can well reproduce the vertical disk structure in this source, showing both the front and back of the flared disk which is undergoing Keplerian rotation.