Astrochemistry at cloud scales: warm vs cold deuteration in Orion

Supervisor: Alvaro Hacar

Contact information: alvaro.hacar@univie.ac.at

Expected duration: 9 months

Project description & Goals:   

Deuterated molecules are regularly used a probes of the densest phases of early-star formation (see Millar et al 2005 for a review). Thanks to the increased sensitivity of sub-mm telescopes such as ALMA, deuteration is nowadays employed on studies from dense cores to massive star-forming regions as density selective tracer and it is proposed as chemical clock (e.g. see Barnes et al 2016). The origin of deuterated species and their emission properties in molecular clouds is, however, matter of strong debates due to the multiple formation pathways of several deuterated species (warm vs cold deuteration; see Salinas et al 2016 for an example). In a recent observational campaign, we have observed a series of deuterated species in the Orion A cloud. Our results show different deuteration levels as function of temperature. This project aims to investigate how the two current chemical scenarios proposed for deuteration in clouds, namely, warm and cold formation routes, can explain the emission distribution observed in this prototypical region.

Working plan & Milestones (including final thesis):

  1. Literature review on ISM gas deuteration
  2. Production of line maps in Orion
  3. Comparison with gas temperature measurements
  4. Analysis of the different deuterated species and their properties
  5. Write thesis

Requirements / special skills:

Knowledge on ISM and star-formation. Basic python knowledge is recommended

References:

[1] Millar et al 2005 (General overview)

[2] Barnes et al 2016

[3] Salinas et al 2018