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What is your position or role in the DESI project?
I’m a researcher at LLNL working on the DESI operations team.

Where were you born? 
I was born in St. Louis, MO.

Where do you live now?
I live in San Leandro, CA, just south of Oakland.

What do you as part of DESI? 
My recent focus has been on testing the accuracy of the fiber positioning and finishing the imaging survey.  I also work on the telescope scheduling.  My work is entirely on the software side, so on a day-to-day basis I write code and make plots.  Finally, I think a lot about how systematics in the imaging can imprint onto the maps we’ll make with DESI.

What is the most interesting or exciting thing about DESI?
The scale of the projects we’re working on is just awesome, in a number of senses:

• largest map of the universe
• largest map of the Milky Way
• millions of spectra, thousands of fibers, tens of spectrographs

It is thrilling to see all of this come together.

Any advice for an aspiring scientist?
Learn to program!  There is a ton of interesting stuff waiting to be found in real scientific data, and you can find it from home today using just a computer.

What do you do for fun? 
Recently, I spend a lot of time building structures with and reading to my two-year-old son.  I also hike, play frisbee, and read to myself.

What is your position or role in the DESI project?

I’m a theoretical cosmologist, who also has a lot of expertise in redshift surveys through the WiggleZ Dark Energy Survey and the Australian Dark Energy Survey (OzDES) on the Anglo-Australian Telescope.  At the moment I’m helping lead the visual inspection of survey validation data, focussing on quasars.  I am also helping out on the DESI membership committee and external collaborator committee.

Where were you born?

I was born in Sydney, Australia.

Where do you live now?<

I now live in Brisbane, Australia.

What do you as part of DESI? 

At the moment I am spending a lot of time looking at some of the first spectra to come through the DESI instrument.  We are making sure the spectra are of high quality (they’re amazing!) and that our analysis software is giving the correct results for the redshift of each object we look at.

At the same time I’m still working on cosmology theory, and seeing how our data can best test theories of dark energy and dark matter that go beyond our standard cosmological model.

What is the most interesting or exciting thing about DESI?

I think one of the coolest things DESI will do is measure the mass of neutrinos.  When starting out in cosmology I never thought that making the largest ever map of the distribution of galaxies in the universe would help us understand the properties of one of the most enigmatic particles in the standard model of particle physics.  But the neutrino mass has an impact on the formation and growth of structure in the early universe, so we can detect its effects with DESI.  Feels to me like a great demonstration of the fundamental interconnectedness of all things (to borrow a Douglas Adams quote).

Any advice for an aspiring scientist?

Enjoy it.  It’s a privilege to be able to do research.  It’s an amazing career.  However, I see many junior researchers stressing over their future, when they really don’t need to!  There are so many great things you can do with the experience you gain from a PhD, and your skills will be in high demand in all sorts of industries.  My trick to stay relaxed and happy in research is this: don’t go into it expecting to do it forever, and don’t stress about whether you’ll get your next job in research or not… just be appreciative of the time you do get to do it.  Funnily enough if you use that technique, you may just find yourself succeeding beyond your wildest dreams!  I once asked my PhD supervisor if I was doing okay in my PhD.  He asked me “Are you enjoying it?”  I responded, “Yes.”  So he said, “Then you’re doing it right.”

There’s lots of other advice I could give, but that’s my main one.

What do you do for fun? 

My main fun-time thing to do is play Ultimate frisbee.  I’ve played all sorts of sports over my life, but Ultimate is the one that has occupied me since my PhD.  I have played all around the world, and represented Australia at seven world championships.  I love it, and the people-skills, leadership, and resilience I learnt from playing sport has definitely helped me in my career as an astrophysicist.

What is your position or role in the DESI project?

I am a core member of the Data Systems team, the group which is responsible for taking the “raw” observations from DESI and delivering science-ready data for the rest of the collaboration. I am also
actively involved in the DESI imaging surveys (check out legacysurvey.org/viewer to tour around the sky!), and the group which is responsible for choosing the targets that DESI will observe.

Where were you born?

I was born in Athens, Greece to a Greek father and an American mother, but moved to San Diego, California when I was eight years old. I grew up, as my father would say, a “beach bum!”

Where do you live now?

My family—my wife and two boys, aged 8 and 12—and I live near Albany, New York, about three hours north of New York City, where I am a physics professor at Siena College, a small private liberal arts college. We own a nice home on about half an acre, have a great dog, and raise chickens!

What do you do as part of DESI?

I spend between 20%-40% of my time on DESI, depending on how busy I am with teaching! Most of my time right now is spent in support of the imaging surveys, making sure that DESI will turn its powerful spectroscopic fibers on the “right” distant galaxies and quasars, which will tell us about the energy content and evolution of the universe.

What is the most interesting or exciting thing about DESI?

DESI is an incredibly ambitious and powerful instrument and project, which is tackling one of the most important outstanding problems in physics and arguably all of science—what is the physical nature of dark energy? The answer to this question will lead to new discoveries beyond our current knowledge, which is very exciting! It’s also a privilege to be working with such a bright and dedicated group of engineers and scientists. Tackling questions at the frontier of knowledge is what originally drew me to astronomy, and it’s humbling to be involved in the next 5-8 years of cutting-edge discoveries.

Any advice for an aspiring scientist?

My advice for an aspiring scientist is three-fold: First, be passionate about what you do; be curious, open to new ideas and perspectives, and strive to learn as much as you can at all times. Second, learn to code! Of course you should learn as much physics, astronomy, and math as you can, but I have found that being proficient with a programming language is enormously powerful and useful. And finally, learn to write well. The key to science is being able to communicate clearly and effectively.

What do you do for fun?

Most of my fun, free-time is spent with my family. I coach all my kid’s sports teams, including my younger son’s travel baseball team. I also love gardening, tackling “do-it-yourself” projects around the house, and exercising!

What is your position or role in the DESI project?

I am co-organizing the work in relation with a sample of 10 million bright galaxies (Bright Galaxy Survey, BGS) that DESI will observe at low redshifts. I am also in charge of organizing the DESI meeting in my research group at the Institute for Computational Cosmology at Durham, in the UK.

Where were you born?

I was born in France, in the suburb of Paris. I did all my studies in France, including my PhD.

Where do you live now?

Since January 2019, I live in Durham in the UK. I have started a postdoc at Durham University.

What do you do as part of DESI? 

DESI has been designed to understand the late-time acceleration of the expansion of the universe, the so-called dark energy. My first contribution to DESI is related to the Bright Galaxy Survey (BGS): since January 2019, I have been working on the selection of BGS targets from the imaging surveys that DESI will spectroscopically observe. For this project, I am co-supervising a PhD student at Durham, which means that we meet every week to have an update on the progress he made, we define the next steps, and we identify the issues. DESI has just started a very exciting period with the first spectra, which means that we can actually start testing our selection with real data. I am involved in these tests, such as: do we obtain the density of objects we expect? In parallel, I am also working on personal research projects. For instance, I developed a new method to measure the cosmic distance using BAO which is based on the cross-correlation between a sample of spectroscopic quasars from eBOSS and a sample of photometric galaxies from DESI imaging surveys.

What is the most interesting or exciting thing about DESI?

DESI is the first new generation of sky surveys which is actually taking data, which means that this period is very exciting and the next 2-3 years will be super exciting as we will be analysing the first data with an unprecedented precision to obtain information on the late-time acceleration of the cosmic expansion. I remember that when I was looking for a postdoc after my PhD, I only applied to institutions who were involved in DESI.
There are many personal things that I find really exciting in my job:

• I learn something new almost every day and with DESI this is even more true as we are pushing the limits in terms of instrument, photometry, size of the samples…

• I am able to measure and interpret parameters that describe the universe, like the evolution of the distances between galaxies! And with DESI we should be able to say whether this mechanism has constant properties (like a cosmological constant) or whether it varies with time (dark energy models). We will also test our theory of gravitation based on General Relativity (GR) and see whether it is still valid at cosmological scales. If not, can we explain the late-time acceleration of the expansion by modifying GR?

In general, what I find the most interesting in research is the fact that there is no book that can tell me what the next step is, I have to find it myself!

Any advice for an aspiring scientist?

I will give the advice that I found the most relevant when I followed a training organized by the program L’Oreal For Women in Science (In 2018 I received one of the 30 fellowships they propose every year for female PhD students and postdocs in science):

• Believe in yourself and in what you can do

• Go step by step: it may sound unfeasible to become an astrophysicist because the studies are long and competitive but try to succeed every year as best as you can and one day you will realize that tomorrow this is your PhD defense!

• Go for it: size the opportunities

• Get out of your comfort zone

What do you do for fun?

My day-to-day work is intellectual only so I need and I love doing physical activities when I don’t work: I love hiking, running and swimming, sports in general, it helps me regenerating. I also love the music, I would like to sing again in a choir and in a band and I play the piano.