Nordic Optical Telescope, La Palma, Spain   —   One of my favorite places on Earth!

I'm an astrophysicist working on galaxy evolution,
chemical enrichment and interstellar medium.

During the long Danish winter nights, I always used to look out my window and wonder what was out there. Later I went on to study physics and astronomy at the University of Copenhagen where I obtained my PhD in 2015. During my PhD, I finally got a chance to live my childhood dream of observing at a big telescope. Since then I have gone observing at some of the best observatories in the world -- my all-time favorite remains the Nordic Optical Telescope on La Palma, Spain (shown on the picture above). My research focuses on the evolution of galaxies in the distant universe, specifically how the gas in galaxies shapes their evolution.

News

May 2023 | New publication! The article presenting our Purely Astrometric Quasar Survey is now available in The ESO Messenger. We are extremely excited to start collecting data in just a bit over a year from now. See also our survey website.

Sep 2021 | We studied the chemical composition of the gas in our own Milky Way and found that this is far less homogeneous than previously assumed. Thanks to Annalisa De Cia for including me on this exciting project! See our Press Release from the University of Geneva or read the full article in Nature.

CV

Education:

  • 2015 — Ph.D. in Astrophysics, Dark Cosmology Centre, University of Copenhagen, Denmark
  • 2013 — Master's degree, Dark Cosmology Centre, University of Copenhagen, Denmark
  • 2009 — Bachelor's degree, Niels Bohr Institute, University of Copenhagen, Denmark

Research Experience:

  • Jan 2022 : Centre de Recherche Astrophysique de Lyon, France
    Astronome-Adjoint (associate astronomer)
  • Feb 2021 — Dec 2021 : University of Geneva, Switzerland
    Senior Postdoctoral Researcher
  • Jan 2016 – Feb 2021 : Institut d'Astrophysique de Paris, France
    Postdoctoral Researcher
  • Dec 2012 – Dec 2014 : European Southern Observatory, Santiago, Chile
    Ph.D. Studentship
My full CV is available in pdf format (last updated: June 2023).

My list of publications is available in pdf format (last updated Jan 2022) or via ADS.

My PhD thesis entitled Galaxies in the early universe characterized in absorption and emission is available on arXiv.

My Projects

I am currently working on various projects related to the evolution of galaxies in the distant universe. Below I highlight some of my key projects.

The Purely Astrometric Quasar Survey

During my PhD we started a series of dedicated spectroscopic surveys to find red quasars that were missed in other spectroscopic surveys. After more than 10 years of searches we are now able to carry out the first large-scale quasar survey without any pre-selection on colors using the upcoming 4MOST instrument.
You can read more on our survey website.

Missing photons reveal galaxies hiding in the dark

Read more about my latest article and how we can study galaxies without seeing them. Go to the story.

Dissecting a distant galaxy

In this work I have studied a very rare alignment of two galaxies in front of a quasar. The strong gravitational field of the first galaxy bends the light of the quasar and makes it appear like two separate images in the sky. This effect is known as gravitational lensing.
Read more...

Fitting Absorption Lines: VoigtFit

I have developed a Python code to fit the absorption lines that we observe. If you are interested, you can read more on the VoigtFit website or on my GitHub page.

Finding Red Quasars

I'm working on ways to identify quasars with very red colors in an attempt to find quasars that are obscured by dust in foreground absorption systems. The dust grains in the foreground system causes the background quasar to look red.
Read more about the dedicated surveys...

Contact Me

You can get in touch with me by e-mail (jens-kristian.krogagerfoo@baruniv-lyon1.fr) or via my social media accounts (see the bottom right panel).
I'll get back to you as soon as possible.