Project affiliation: A1
Supervisor: Prof. Dr. Frank Bertoldi
Hosting institution: National Radio Astronomy Observatory (NRAO),
Socorro, New Mexico, USA. Dr. Chris Carilli and Dr. Steve Myers
Duration of stay abroad: 08.07.2016 - 06.08.2016

Introduction

Since 2015 I am an Astrophysics doctoral candidate at the Argelander Institute for Astronomy (AIfA , University of Bonn) within the International Max Planck Research School of Astronomy and Astrophysics (IMPRS , Max Planck Society). I am working within the project A1 of the SFB 956 'Understanding Galaxy Assembly' under the supervision of Prof. Dr. Frank Bertoldi and Dr. Alex Karim.

My doctoral project is focused on the study of the physical conditions of the star forming gas throughout cosmic time, which is paramount to shed light on the processes that shape galaxies and govern the formation of stars in the universe. As part of my doctoral thesis, I am probing the conditions of the molecular gas which is fueling a intense star formation episode in AzTEC/159, an early galaxy at z=4.567 exhibiting a rapidly spinning gas disk. This system profits from unique high-resolution ALMA line/continuum coverage and hence unique constraints on the gas kinematics. It hence provides a remarkable laboratory to study the physics of star formation in early disk galaxies.

Experiences

We secured CO (2-1) line observations in early 2016, a tracer of the molecular gas, with the Very Large Array (VLA/NRAO) as part of the observing program: ‘Fuel and consumption of a massive rotating disk galaxy after 1.3Gyr after the Big Bang’ (project code 15B-280). During my stay at the NRAO in Socorro (New Mexico), within the student exchange program of the SFB 956, I analyzed the data obtained with the VLA in combination with proprietary IRAM/NOEMA CO(5-4) data for the same source. I mainly worked with Dr. Chris Carilli and his PhD student Gareth Jones on the scientific analysis of the combined data set and to prepare a manuscript for subsequent scientific publication.

Additionally, I discussed imaging strategies for the JVLA-COSMOS Large Program with NRAO-staff in preparation of my longterm thesis project on radio/synchotron-shape measurements of star forming galaxies throughout cosmic time. Given the uniqueness of this pioneering data set and corresponding challenges, hands- on interaction with key VLA-survey personnel, including Dr. Steve Myers, was mandatory.

During my stay in Socorro at the Domenici Science Operations Center (DSOC) I had the chance to experience a different research environment, but overall to work on my international network. From my perspective, scientific collaboration should also rely on social interaction. A farewell BBQ, a guided tour by Gareth at the VLA and pleasant talks over lunch at the New Mexico Tech cafeteria and local restaurants made my stay quite enjoyable.

Conclusions

Certainly, this was a very fruitful stay in which I improved my scientific research skills and gained a deeper understanding on the start formation proceses at the early Universe. Moreover, I made considerable progress on the upcoming publication in relation to the physical conditions of the star forming gas in AzTEC159. On the other hand, interaction with friendly staff of the DSOC gave place to engage in international networking. This stay significantly contributed to my profesional career development, I strongly recommend to all doctoral candidates within the SFB 956 to profit from the student exchange program.