Fermilab Today

What brought you to Fermilab?
The CMS group at Fermilab is actually quite big. CMS is one of the four major experiments at the Large Hadron Collider at CERN. Fermilab is kind of the center of the CMS collaboration in the United States, so it's a natural place to go if you work on CMS or want to work on CMS.

What does your typical workday look like?
I do a lot of software development, so I spend a lot of time looking at a computer, and sometimes I'm in my lab at Fermilab tinkering with electronics and things like that. I also go to a lot of meetings, which is typical for people in CMS.

I understand that you coordinate the HATS program. What is HATS?
HATS stands for Hands-on Tutorial Seminar. It's run as part of the LHC Physics Center at Fermilab, and it's a series of tutorial sessions that we put together for graduate students, undergraduate students and postdocs. It's meant to give them exposure to doing some aspect of high-energy physics, and especially on CMS, that is more targeted toward a specific topic.

For example, somebody gives a talk on what is involved in electron reconstruction, what subdetectors are important, what typical signatures of an electron look like in these subdetectors. From there they go through examples of how to use this software, sift through the data and pick out objects that look like electrons. Students and postdocs can then use these tools in their analysis work to do whatever physics they are interested in studying.

What is the most exciting part of your job?
In general looking at new data is always the most exciting thing. There's usually this one- to two-week period where you're sifting through all this very fresh data. You're trying to understand what's there, if there's anything new there, or if what you think is new is actually something new or is just a different way of looking at the same old things that people have been looking at for years. The most exciting part is when you get to look at the data sets and try to see if something is there that no one else has seen before.

What do you like to do when you're not sifting through data?
When I'm here at CERN I like to play a lot of board games. Not Monopoly — we tend to play much geekier games. Classic examples are Carcassonne or Settlers of Catan. There's a whole world of board games that I think the general population isn't aware of.

—Ashley Black

In Brief

Wilson Hall HVAC outage this weekend, building still open

Wilson Hall HVAC service will be interrupted beginning today at 3:30 p.m. and will remain off until Sunday at about 5:30 p.m. There will be no air conditioning in the building during this time.

Wilson Hall will remain open during regular hours.

In the News

Age of the neutrino: Plans to decipher mysterious particle take shape

From Nature, Aug. 12, 2015

As researchers at CERN, Europe's particle-physics laboratory near Geneva, dream of super-high-energy colliders to explore the Higgs boson, their counterparts in other parts of the world are pivoting towards a different subatomic entity: the neutrino.

Neutrinos are more abundant than any particle other than photons, yet they interact so weakly with other matter that every second, more than 100 billion stream — mainly unnoticed — through every square centimetre of Earth. Once thought to be massless, they in fact have a minuscule mass and can change type as they travel, a bizarre and entirely unexpected feature that physicists do not fully understand (see 'An unconventional particle'). Indeed, surprisingly little is known about the neutrino. "These are the most ubiquitous matter particles in the Universe that we know of, and probably the most mysterious," says Nigel Lockyer, director of the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois.

Frontier Science Result: NOvA

Muon neutrinos make a disappearance

This plot shows the energy spectrum of detected muon neutrino events in the NOvA detector compared to the much larger signal that would be expected if there were no neutrino oscillations.

Neutrinos are ghosts; everywhere around us, we unknowingly swim through billions of them constantly without ever interacting. Thankfully both natural and man-made sources such as the Fermilab NuMI beam produce copious numbers of higher-energy neutrinos. This abundance means that they can be spotted with very large detectors despite their ghostly nature. They come in three types and are known for their strange properties, such as their tendency to oscillate, or change from one type into another, similar to tossing a basketball and finding a mere ping pong ball where it lands.

Oscillations depend on a neutrino's energy and distance traveled, and by using a man-made neutrino beam we can carefully choose where we put our detectors in order to maximize this effect. This was done in NOvA, the U.S. flagship long-baseline neutrino experiment with a massive five-story, 14,000-ton far detector located in remote northern Minnesota, 500 miles from Fermilab, which only recently released the analysis results from its first batch of data.

NOvA looks for both the disappearance of muon type neutrinos (which make up the NuMI beam) as they oscillate away, and the appearance of electron type neutrinos that wouldn't be there without oscillations. The included plot shows the energy distribution of muon neutrinos detected, where NOvA would expect to see 201 muon neutrinos if there were no oscillations, but only 33 were actually seen — clear evidence of oscillations.

Muon neutrinos are detected by seeing muons resulting from their interactions, and one analysis challenge was to distinguish the muons from neutrinos from tens of millions of very similar looking cosmic ray muons. Only one or two of these 33 events are estimated to be cosmic rays surviving the sophisticated event selection, however.

The shape of the energy distribution contains further information that allows extraction of precise parameters detailing the inner workings of the oscillations. These NOvA results are already competitive with the world's best information on these parameters with less than 10 percent of the planned data, and this result will quickly improve.

The information gleaned from these rare neutrino interactions has far-reaching implications and can teach us about things like the evolution of the universe, how a supernova works and possibly even why the universe is made of matter and not antimatter. We still have a long way to go in solving all their mysteries, but NOvA is a big step along the path to understanding these little ghosts all around us.

—Kirk Bays, California Institute of Technology

This analysis is the subject of these physicists' Ph.D. theses. From left: Michael Baird (Indiana University), Nicholas Raddatz (University of Minnesota), Dominick Rocco (University of Minnesota). Not pictured: Susan Lein (University of Minnesota).

Photos of the Day

Double rainbow

A rainbow arced over Fermilab Monday. Photo: Kathy Zappia, ESH&Q

Actually, two rainbows did. Photo: David Esterquest, ESH&Q

In the News

Mystery deepens: Matter and antimatter are mirror images

From Live Science, Aug. 12, 2015

Matter and antimatter appear to be perfect mirror images of each other as far as anyone can see, scientists have discovered with unprecedented precision, foiling hope of solving the mystery as to why there is far more matter than antimatter in the universe.