Thesis Topic: The interstellar medium (ISM) in high-redshift galaxies

 Thesis Supervisor: Paola Andreani

External Supervisors:

Padelis Papadopoulos

(Aristotle University of Thessaloniki, Greece)

Francesca Pozzi

(University of Bologna, Italy)

Chentao Yang

(ESO Chile)

Zhi-Yu Zhang 

(Najin University, China



The interstellar medium of high redshift galaxies can be investigated through the emission lines of the atoms and molecules present in the various phases of the gas in the galaxy disc and the thermal emission from dust. Tracing the various stages of the gas (warm, cold, molecular) and its relation to the dust is key to understand the initial conditions of star formation and the type of the stellar initial mass function, therefore it provides information on the star formation processes in the galaxy.
Many Atomic and Molecular lines are accessible with the ALMA array and with submm single dishes like APEX and several observations are available for high redshift sources. In particular key is the combination of molecule emission (CO and others) and the Atomic Carbon lines which when studied together are able to shed light on the thermal state of the ISM and on the mechanism at play heating the gas and the dust.
The project aims at looking at ALMA and APEX data of various sources at high and low redshift and at making a physical study of the status of the ISM by investigating Atomic Carbon, CI, ionised Carbon, C+, and Carbon Monoxide, CO, and other tracers of the warm and cold gas present in star-forming regions of the galaxy discs.
The thesis will be tailored to the student's preference and skills.


  • Solomon and Vanden Bout, "Molecular Gas at High Redshift", 2005, Ann Rev Astr. Astroph 43, 677
  • Papadopoulos and Geach, "Molecular and Atomic Line Surveys of Galaxies", 2012, ApJ 757, 157
  • Carilli and Walter, "Cool Gas in High Redshift Galaxies", 2013, Ann Rev Astr. Astroph 51, 105
  • Papadopoulos et al, "New places and phases of CO-poor/CI-rich molecular gas in the Universe", 2018, MNRAS 478, 1716
  • Andreani et al. "Extreme Conditions in the molecular gas of lensed star-forming galaxies at z~3", 2018, A&A 615, 142
  • Zhang et al. "Stellar populations dominated by massive stars in dusty starburst galaxies..", 2018, Nat 558, 260