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Staff at DAWN
Sune ToftCenter Director | The Cosmic Dawn Center (DAWN) |
Thomas GreveCenter Co-Director | The Cosmic Dawn Center (DAWN)DTU Space ![]() My research deals with the origin and evolution of massive galaxies. I study them using radio and optical telescopes on the ground and in space. Interfacing with numerical simulations is an important part of this work. I enjoy teaching, supervising students, as well as public outreach. |
Guarn Elizabeth NissenSenior Coordinator | The Cosmic Dawn Center (DAWN)
I have held the position of Coordinator for the Genotoxic Stress Center of Excellence (GSC) at the Danish Cancer Society. Like DAWN, GSC was also primarily funded by the Danish National Research Foundation (DNRF). I have a BcS degree from Fontbonne University in St. Louis MO. |
Johan Peter Uldall FynboSection Leader | The Cosmic Dawn Center (DAWN)
I teach a range of courses in astronomy ranging from introductory astronomy courses to master level courses. In collaboration with colleagues from the University of Aarhus, I also teach a summer course in astronomical observations at the Nordic Optical Observatory on La Palma. Beyond academia, I am a frequent contributor to public outreach, I am vice chairman of the Danish Astronomical Society and I give many public talks on science. |
Helena Baungaard-SørensenSecretary| The Cosmic Dawn Center (DAWN)
Before onboarding DAWN, I studied and achieved a MSc in Global Marketing & Innovation Management. Afterwards I have worked as a financial assistant in the NGO’s of the Danish Refugee Council of Youth and the National Lung Association. One of my favorite quotes is: “Keep your eyes on the stars and your feet on the ground". |
Peter Daniel Johannsen
Since March 2021 I have been the student helper at DAWN; my role is primarily overseeing the websites, but I will also be helping Guarn and Helena as much as I can, with different administrative tasks. In my free time I play disc golf and dedicate many hours to bouldering. I’ve played the piano for about 15 years and enjoy travelling through Europe on my bicycle. |
Charles SteinhardtAssociate Professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
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Charlotte MasonAssociate Professor | The Cosmic Dawn Center (DAWN)
I work at the intersection of theory and observations, focusing on galaxy formation and evolution, and the galaxy - dark matter connection, in the early Universe. My research combines theoretical models and simulations with statistical analysis to interpret observations of galaxies. In particular, I have focused on finding new ways to measure the process of hydrogen reionization - the Universe’s final phase transition, which ended approximately one billion years after the Big Bang and was likely caused by the very first stars and galaxies. By understanding how reionization occurred we can infer the properties of the universe’s first galaxies, which are probably too rare and faint to detect directly. I am involved with (mostly near-IR) observations from our largest telescopes in space and on the ground: Hubble, VLT, Keck, and MMT, and I am excited to be among the first users of the James Webb Space Telescope in a Early Release Science program to observe the earliest galaxies. |
Darach Jafar WatsonAssociate Professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
I teach a range of courses in physics and astronomy ranging from experimental quantum mechanics to observational astrophysics. I have supervised a large number of students at all levels from BSc to PhDs. |
Georgios MagdisProfessor | Danish Technical University (DTU)Associate Professor | The Cosmic Dawn Center (DAWN) DTU Space Niels Bohr Institute, University of Copenhagen
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Gabriel BrammerAssociate Professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
My research involves studying the formation and evolution of galaxies across much of cosmic time, from relatively nearby massive, evolved objects to infant galaxies at the current limit of the observable Universe. I discover and characterize these objects by and exploiting large imaging and spectroscopic surveys with the Hubble Space Telescope, and I am helping to develop next-generation projects with the Guaranteed Time Observer and Early Release Science programs on the James Webb Space Telescope, due to be launched in 2021. I also enjoy photography with much smaller glass, including night-sky astrophotography and analog film. |
Peter JakobsenAffiliated Professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
While at ESA I served as the Project Scientist for Europe's participation in the Hubble Space Telescope (HST) until 1995. From 1997 to 2011 I held the same position for Europe's contributions to the James Webb Space Telescope (JWST). In the latter capacity I oversaw the design and development of the NIRSpec multi-object spectrograph onboard JWST, an instrument that I am still actively involved in. My scientific interests include astronomical space instrumentation, applied statistics, and the physics of the early universe with emphasis on quasar absorption lines and reionization. I also engage in scientific evangelism, and periodically give public lectures at high schools and other venues across Denmark. |
Francesco ValentinoAssistant professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
I moved to Copenhagen as a DARK fellow at the Dark Cosmology Centre and then I joined the Cosmic Dawn Center as a DAWN fellow, working in close collaboration with Prof. Georgios Magdis on the project “Gas to Stars - Stars to Dust: Tracing star formation across cosmic time” supported by a Velux Foundation Grant. I obtained my PhD in 2016 from the Université Paris Diderot (Paris 7) under the supervision of Dr. Emanuele Daddi at the Commissariat à l’Énergie Atomique (CEA) in Saclay. |
Allan Hornstrup
Associate professor | The Cosmic Dawn Center (DAWN) DTU - Space My interests are focused on cosmology, including the large scale structure of the universe; on space instrumentation and space research in general. I also fancy exoplanetary studies, including the search for extraterrestrial life. I enjoy physics, teaching, public outreach and management. In cosmology, I have studied clusters of galaxies in general (the content) and in particular worked on using clusters of galaxies for cosmological purposes e.g. through the cluster development with time. Since 2007, I have been head of astrophysics at DTU Space and later included atmospheric physics. The group has grown from about a dozen to now almost 60 scientists and technicians. I hold a MSc in astrophysics, a PhD in technical physics and an executive MBA. |
Lise Bech ChristensenAssociate professor | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
My research topics focus on the nature of gas and stars in and around distant galaxies with observations from the largest telescopes. Specifically, I investigate galaxy chemical evolution through quasar- or gamma-ray burst absorption lines, and via strong gravitational lensing. On the technical side, I work to facilitate Danish participation in instrumentation projects for the next generation of large astronomical telescopes. I teach courses in extragalactic astrophysics and data handing at Bachelor and Masters levels at the University, and supervise a number of students at all levels. |
Kasper Elm HeintzAssistant Professor | The Cosmic Dawn Center (DAWN) I am an Assistant Professor of Astrophysics based at the Cosmic Dawn Center (DAWN) at the Niels Bohr Institute. I received my PhD degree from the University of Iceland in 2019, advised by Prof. Páll Jakobsson. My thesis project was primarily focused on using gamma-ray bursts and quasars as cosmic probes to study the interstellar medium in high-redshift galaxies. |
DAWN Fellows:
Francesca RizzoDAWN Fellow | The Cosmic Dawn Center (DAWN)
I am interested in the ways in which galaxies form and evolve across cosmic time. In particular, my research focuses on galactic dynamics, which is the analysis of the motion of gas and/or stars within galaxies. Through this kind of study, I learn how different physical processes shaped the variety of galaxies that we observe today. You can find more about my research here. I have long been committed to diversity and acted to create an academic environment, which is more inclusive and inviting towards different gender, sexual orientation, ethnic, and socioeconomically underprivileged groups. For this reason, I enjoy giving my contribution to public outreach events. |
Iary DavidzonDAWN Fellow | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
My main goal is to leverage this exquisite data in the exploration of the first 2-3 billion years of universe’s life, investigating star formation mechanisms in primeval galaxies, especially the most massive ones. I am also interested in the connection of these baryonic processes to the underlying dark matter structure. I study galaxy environment also in large-scale surveys (VIPERS) and galaxy clusters (BUFFALO). Before moving to Copenhagen I joined Peter Capak’s group at the California Institute of Technology, contributing to introduce novel machine learning methods in the research field of galaxy evolution. Previously I worked in Marseille (France) within the COSMOS collaboration, and before that I was a graduate student in Bologna, where I obtained my PhD in 2014 under the supervision of Micol Bolzonella and Lauro Moscardini. In the spare time I like playing ukulele and tinkering with my bikes, which is a quite appropriate hobby now that I live in (probably) the best cycling city in the world. |
Seiji Fujimoto
DAWN Fellow | The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
My research interest is the early Universe, including the topics of the formation and evolution of massive galaxies and black holes, the structure formation, and the interplay between a galaxy and its environment. I’m working in international projects of e.g., “The ALMA Large Program to Investigate CII at Early Times (ALPINE)”, “ALMA Lensing Cluster Survey (ALCS)”, and “Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP)”. I also work as one of the external collaborators in the cosmology group in Scuola Normale Superiore headed by Prof. Andrea Ferrara. You will find more details on my personal website. |
Victoria StraitDAWN Fellow | The Cosmic Dawn Center (DAWN)
I am interested in all properties of galaxies at cosmic dawn, including (but not limited to) ionization and escape, age, dust, and size. You can read more about my previous research on my website. |
Aswin P VijayanDAWN Fellow | The Cosmic Dawn Center (DAWN)
During my PhD I have worked on developing a self-consistent dust production and destruction model in the L-Galaxies Semi-Analytical Model. I have also done extensive work in the development of FLARES, a suite of zoom resimulations using the EAGLE simulation physics targeting a range of overdensities in the Epoch of Reionisation. I implemented a line-of-sight dust extinction model to obtain the UV to near-IR SEDs of these galaxies as well as the full SEDs using the radiative transfer code SKIRT. You can find more details about it on my personal website. I wouldn’t say no to a session of squash or badminton and enjoy watching football and making random foods. |
Nina BonaventuraPostdoc | The Cosmic Dawn Center (DAWN)
I received my PhD degree in Physics in 2017 from McGill University under the supervision of Dr. Tracy Webb (McGill Space Institute), for my contribution to the unexpected discovery of significant star formation activity occurring within a special class of galaxies previously known to be ‘dead’ and inactive. Previously, I held a NASA Smithsonian Astrophysical Observatory (SAO) Data Specialist position at the Chandra X-ray Center, working on a variety of scientific and technical projects as a member of the Science Data Systems team. I have also worked as a telescope support scientist at Lowell Observatory while a graduate Master’s student at Boston University, personally utilizing and assisting others in the operation of infrared and optical imaging and spectroscopic instruments. |
Steven R. GillmanPostdoc | The Cosmic Dawn Center (DAWN)
Here at DTU Space, and as part of the Cosmic DAWN Center, my work will focus on preparation for the James Webb Space Telescope (JWST) MIRI GTO observations and the subsequent reduction and analysis of this data in years to come. |
Lijie LiuPostdoc | The Cosmic Dawn Center (DAWN)
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Anton Norup SørensenResearcher | The Cosmic Dawn Center (DAWN)
I received my Masters degree in 1996 from the University of Aarhus, advised by Bjarne Thomsen. |
Bo Milvang-JensenResearcher | The Cosmic Dawn Center (DAWN)
I work on observational extragalactic astrophysics, using optical and infrared spectroscopy and imaging (including narrow-band imaging). In particular I have contributed to the EDisCS project studying cluster galaxies, and the UltraVISTA project studying high-redshift galaxies. I also work on gamma-ray bursts, including their host galaxies, and follow-up of gravitational-wave events. Additionally I am instrument scientist for the NTE (NOT Transient Explorer) instrument being designed and built by the Niels Bohr Institute (PI Johan Fynbo). |
Peter LaursenSenior Scientific and Communication Coordinator
At DAWN, my tasks include arranging workshops, maintaining our website, communicating our science to the public, as well as conducting my own research. My research focuses on galaxies, in particular the light coming from processes that have to do with galaxy formation. I use computer simulations to predict and interpret "real" observations. More specifically, I use hydrodynamical simulations with (Monte Carlo) Lyman α radiative transfer. After my PhD I was a postdoc at the Oskar Klein Centre (Stockholm), the Dark Cosmology Centre (Copenhagen), and the University of Oslo. You can find out more about me, my research, and my outreach activities on my personal website. |
DAWN Associates:
Trity PourbahramiCommunications Consultant| The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
In addition to being a practitioner of communications I am an educator and have designed and delivered a variety of customized trainings as well as a new graduate course on effective oral, written, and media communications. I also enjoy building community through serving on various local, national, and international community groups including the Federation of Zoroastrian Associations of North America and Leadership Pasadena. |
Claudia LagosInternational Associate | The Cosmic Dawn Center (DAWN)
My research involves studying galaxy formation and evolution using state-of-the-art cosmological simulations of galaxy formation and large galaxy surveys. I am the main developer of the new Shark semi-analytic model of galaxy formation and one of the members of the EAGLE Simulations collaboration. I am also a member of several galaxy surveys including several being carried out with the Australian Square Kilometre Array Pathfinder, the Anglo-Australian Telescope and the future 4MOST instrument at Paranal, Chile. |
Kate WhitakerInternational Associate | The Cosmic Dawn Center (DAWN)
As an observational extragalactic astronomer, I study galaxy formation and evolution over the past twelve billion years of cosmic time. My students and I actively collaborate with DAWN, working towards pushing our detection quiescent “read and dead” galaxies even earlier in time (within a billion years of the Big Bang itself!). We would like to understand the detailed physics of the structures and underlying stellar populations of these early massive galaxies. With exquisite Hubble Space Telescope imaging and spectroscopy, we explore the rich uncharted territory of the distant universe and continually piece together an intriguing timeline of the cosmos. I also enjoy dancing, photography, crafting, and spending time with my family. |
Karina CaputiInternational Associate | The Cosmic Dawn Center (DAWN)
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Kristian FinlatorInternational Associate | The Cosmic Dawn Center (DAWN)
I am interested in the processes that couple galaxies with their environments. Although I have previously studied the relationship between galactic outflows and the mass-metallicity relation, the research that I lead nowadays is anchored in detailed comparisons between predictions from cosmological simulations and observations of galaxies, the circumgalactic medium, and the intergalactic medium. My goal is always to learn how observations constrain the feedback processes that regulate galaxy growth and reionization. I enjoy learning Danish, jogging, and playing with my two young children. Long ago (z~10-9) I also played in orchestras; I’m sure I will get back to that at some point. |
Peter CapakInternational Associate | The Cosmic Dawn Center (DAWN)
My research interests focused in two areas: the physical processes that govern the formation and evolution of the most massive galaxies in the early universe (z>2) and large area surveys to measure galaxy properties and probe Dark Energy and Dark Matter. I am a founding member of the Euclid consortia, developed the redshift estimation pipeline and simulations for the NASA SPHEREx mission, and was a member of the WFIRST cosmology science definition teams. I was also principal investigator of the Spitzer Legacy Survey and the SPLASH Spitzer Exploration Science programs which were two of the largest ever carried out on the Spitzer Space Telescope using a year of time. Previously I was lead of the COSMOS project, lead of the CCAT high-z science working group, and leading to effort to produce enhanced imaging products and a source list for the Spitzer archive. I have also been co-organizer of the PHAT project aimed at developing a set of best practices for photometric redshifts and made significant contributions to the GOODS Legacy project including deep imaging of The Hawaii Hubble Deep Field North. |
Desika NarayannanInternational Associate | The Cosmic Dawn Center (DAWN)
My research focuses on theoretical models primarily related to cosmological galaxy evolution, star formation, and the interstellar medium (ISM). I principally develop and utilize large scale numerical simulations to simulate the interplay between small scale star formation, ISM physics, and global galaxy evolution. I love (American) college football, surfing, snowboarding, jam bands, hiking, and hockey. |
Fabian WalterInternational Associate | The Cosmic Dawn Center (DAWN)
My research focuses on studies of the evolution of galaxies and quasars, from the end of cosmic reionization to today. My particular focus is on the studies of the interstellar medium that is a requirement for star formation to proceed. In my research, I intensively use the ALMA, IRAM NOEMA, and VLA radio/millimeter interferometers. In this context I have led a number of large initiatives, such as the THINGS survey of HI emission in nearby galaxies, the HERACLES survey to map the distribution of molecular gas in nearby galaxies, surveys to characterize the interstellar medium in the most distant quasars, and a large ALMA program that studies the molecular gas and dust content in the Hubble Ultra-Deep Field (ASPECS). |
Luis ColinaInternational Associate | The Cosmic Dawn Center (DAWN)
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Pascal OeschInternational Associate | The Cosmic Dawn Center (DAWN) ![]() I am currently an Assistant Professor at the University of Geneva, where I lead a research group “Galaxy Build-up at Cosmic Dawn”. Additionally, I am an International Associate of the Cosmic DAWN Centre. I obtained my PhD in 2010 at ETH Zurich, after which I moved to UC Santa Cruz as a Hubble Fellow (2010-2013) and then to Yale as a YCAA Fellow (2013-2016). Already starting from my PhD studies, my research has focused on understanding the build-up and assembly of the first generations of galaxies based on panchromatic observations. In particular, I use very deep imaging and spectroscopy from the Hubble and Spitzer Space Telescopes, in addition to ground-based follow-up with Keck, VLT, ALMA, and NOEMA. This allows us to trace the galaxy mass build-up out to z~11, when the Universe was only ~400 Myr old, where we have found the most distant galaxy known so far: GN-z11.
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Birgitta Nordstrom
Associate Professor Emeritus | The Cosmic Dawn Center (DAWN)
Niels Bohr Institute, University of Copenhagen
Birgitta Nordström was born in Sweden and studied physics and astronomy at Stockholm University until she was awarded her PhD in 1970. After postdoc positions in Switzerland and Canada, she came to the Niels Bohr Institute in 1972, where she has worked since then as a scientist and in the administration. Her Danish affiliation has been interrupted by several guest professorships in the USA (Center for Astrophysics, Cambridge) and in Europe (Lund in Sweden, Paris in France, Kiel in Germany and Vienna in Austria). Birgitta’s research has been centered around the chemical and dynamical evolution of galaxies, using the Milky Way as a prototype. Her most-cited paper is the Geneva-Copenhagen Survey of the Solar Neighbourhood (Nordström et al. A&A, 2004), which revealed that the structure of the Milky Way disk is much more complex than previously believed. Other large research projects focus on studying probable remnants of minor dwarfs galaxy mergers in the disk and on the oldest and most metal poor stars in the Milky Way halo (Cayrel et al. 2004, Bonifacio et al. 2009) and the formation of the chemical elements in the early Universe (Hansen et al. 2015). Birgitta has also devoted part of her career to work in international organisations such as the European Southern Observatory, the European Space Agency, the International Astronomical Union, and the Journal Astronomy & Astrophysics. She is member and ex-Chair of the Board of Directors of A&A. She represents Denmark in European Astronomical Society and the COST actions ChETEC (ChemicalElements as Tracers of the Evolution of the Cosmos, http://www.chetec.eu/) and MW-Gaia ( https://www.mw-gaia.org/).
John R. Weaver
PhD Student| The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
Previously, I have interned as a summer researcher at the Max-Planck Institute for Astronomy, Leiden Observatory, and the Maria Mitchell Observatory. I am also the project director of the spectroscopy database at the American Association of Variable Star Observers. Beyond academia, I am a frequent contributor to popular science publications, and have been a long-time volunteer at public observatories. |
Meghana Killi
PhD Student| The Cosmic Dawn Center (DAWN)Niels Bohr Institute, University of Copenhagen
Beginning in eighth grade, I underwent intensive training for the prestigious Indian Institute of Technology (IIT) entrance exam. I was accepted into the Mechanical Engineering programme at IIT Kharagpur, but after graduating in 2015, I decided to switch tracks and follow my childhood passion for Astronomy. In 2016, I moved to the US, and began a second Bachelor’s degree in Astronomy at the University of Texas at Austin, where I worked with Dr. Caitlin Casey on submillimeter galaxy observations, and with Dr. Volker Bromm on dark matter theory. Two intense and transformative years later, I graduated with highest honors, and was accepted to DAWN. I am currently studying the origin of various elements in the universe. More broadly, my research interests lie in our cosmic origins, first stars and galaxies, and events in the very early universe just after the Big Bang. |
Vasily KokorevPhD Student| The Cosmic Dawn Center (DAWN)
I received my master’s degree in Physics with Astrophysics at the University of Sussex in 2018, where I have carried out work related to the 21 cm radio astronomy, while being advised by Mark Sargent. |
Clara Giménez ArteagaPhD student| The Cosmic Dawn Center (DAWN)
I obtained my Master's degree from DAWN in 2020, and my Bachelor's degree in Physics in 2018 at the University of Barcelona, where I am originally from. |
Malte BrinchPhD Student| The Cosmic Dawn Center (DAWN) I am a PhD student at the DAWN DTU who formerly defended my MSc at KU, DAWN NBI. My thesis focuses on reverberation mapping of AGN, so as to use them as Distance measurements. As part of my PhD at DAWN, I will be working with Thomas Greve on characterizing the dense molecular gas content in gravitationally lensed starburst and normal galaxies and relate these results to surveys of the dense interstellar medium in local galaxies. I will also work on GISMO 2mm surveys with the Greenland Telescope. I plan to travel to the Thule air base in the fall of 2020 to observe with the GLT. |
Vadim RusakovPhD student| The Cosmic Dawn Center (DAWN)
I received a Masters degree from the University of Surrey in 2019 studying galaxy evolution in the Local Group with Carme Gallart & Matteo Monelli, while spending part of my degree at the IAC (Tenerife), and a Masters degree from University College London in 2020 doing a project in computational astrophysics with Thomas Greve.e I am advised by Charles Steinhardt. I am part of research into mechanisms driving the active and quiescent stages of high-redshift galaxies, which is motivated by a mismatch in theoretical predictions and observations of galaxy assembly in the early universe. I am also keen to work on computational problems in research. |
Katriona (Kate) Mai Landau GouldPhD student| The Cosmic Dawn Center (DAWN)
Before deciding to study galaxies, I was interested in particle and astroparticle physics, and had fantastic opportunities to work on experimental projects relating to both cosmic rays and neutrinos at Jodrell Bank Center for Astrophysics and later CERN. I’ve also been lucky enough to do both cosmology and galaxy summer research projects at the Institute of Cosmology and Gravitation and the University of Oxford. When I’m not doing research I enjoy powerlifting, astronomy outreach, pursuing creative projects and exploring the wonderful city of Copenhagen.
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David BlánquezPhD student| The Cosmic Dawn Center (DAWN)
I received my master’s degree in Earth and Space Physics and Engineering at the Technical University of Denmark in 2021, after having completed my Bachelor’s degree in Mechanical Engineering (2019) at Tecnun - Universidad de Navarra in San Sebastian (Spain), where I am originally from. |
Ting-Yi LuPhD student| The Cosmic Dawn Center (DAWN)
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Gonzalo PrietoPhD student| The Cosmic Dawn Center (DAWN)
My previous research was focused on young galaxies near the epoch of reionization and the intersection between Lyman Break Galaxies and Lyman Alpha Emitters. At DAWN, I am working with Charlotte Mason as my advisor on the topics of the timeline of Reionization and the morphology of ionized bubbles during Reionization, all of these through the observation and modeling of Lyman Alpha Emitters.
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Albert Bjerregård SneppenMSc Student| The Cosmic Dawn Center (DAWN)
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Jiaming YaoMSc Student| The Cosmic Dawn Center (DAWN) I am a Master student who working on my thesis under the direction of Francesco Valentino and Georgios Magdis. My current research focuses on selecting out quiescent galaxies from data and obtaining multiple properties of them by studying SEDs. Exploring these "dead" galaxies can help us get a glimpse of the early universe and learn how galaxies evolve. My interests focus on observation and data analysis. |
Guozhen MaMSc Student| The Cosmic Dawn Center (DAWN)
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Han LeiMSc Student| The Cosmic Dawn Center (DAWN)
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Simone Vejlgaard NielsenMSc Student| The Cosmic Dawn Center (DAWN) I am a master's student working on my thesis under supervision of prof. Johan Fynbo and postdoc Kasper E. Heintz. My thesis will be focusing on using gamma-ray bursts and quasars as sources to study various properties of the interstellar medium in high-redshift galaxies. Furthermore, I am also very interested in dust-obscured quasars and how the current selection cuts are biased against these quasars, which means that I have previously been involved in projects using modern, unsupervised machine learning methods to de-bias object classifications. |