Fermilab Today Result of the Week

The camera on the South Pole Telescope measures minuscule fluctuations in the polarization of cosmic-microwave-background light across the southern sky. Photo: Jason Gallicchio, University of Chicago

In a study published in Physical Review Letters, Fermilab and University of Chicago scientist Brad Benson and colleagues use the polarization, or orientation, of the cosmic microwave background to calculate the masses of enormous galaxy clusters using a new mathematical estimator. This is the first time that scientists have measured these masses using the polarization of the CMB and the novel estimation method.

By Catherine N. Steffel. You can read the article at the Fermilab News web site.

The display shows the decay of a heavy neutrino as it would be measured in the MicroBooNE detector. Scientists use such simulations to understand what a signal in data would look like. Image: MicroBooNE collaboration

Neutrinos have baffled scientists for decades as their properties and behavior differ from those of other known elementary particles. Their masses, for example, are much smaller than the masses measured for any other elementary matter particle we know. They also carry no electric charge and  interact only very rarely – through the weak force — with matter. At Fermilab, a chain of accelerators generates neutrino beams so researchers can study neutrino properties and understand their role in the formation of the universe.By Owen Goodwin, Davide Porzio, Stefan Söldner-Rembold and Yun-Tse Tsai .

You can read the entire article here, at the Fermilab News website.

Fermilab scientist Matt Hollister works on the world’s largest dry dilution fridge, which will be used for the SuperCDMS experiment at SNOLAB. Image: Reidar Hahn, Fermilab

After riding in a cage with nickel miners, walking down drifts and stopping at the dry, SuperCDMS scientists enter their shotcrete igloo of discovery deep underground.

Translating this out of mining lingo: After taking an elevator down a two-kilometer mineshaft with nickel miners, Fermilab scientists walk through nearly two more kilometers of tunnels and then shower and change before entering the white-walled cavern that will house the Super Cryogenic Dark Matter Search, an experiment that will look for dark matter particles with masses ranging from half to 10 times the mass of a proton.

By Catherine N. Steffel. You can read the entire article at the Fermilab News web site.

The IceCube experiment in Antarctica.

Underneath the vast, frozen landscape of the South Pole lies IceCube, a gigantic observatory dedicated to finding ghostly subatomic particles called neutrinos. Neutrinos stream through the Earth from all directions, but they are lightweight, abundant and hardly interact with their surroundings. 

The IceCube detector consists of an array of 86 strings festooned with more than 5000 sensors, like round, basketball-sized Christmas lights. They reach more than 2 kilometers (more than 1 mile) down through layers of Antarctic ice that have accumulated over hundreds of thousands of years.

By Diana Kwon. You can read the article at the Symmetry Magazine web site. 

Ana Amelia Machado

Ettore Segreto

The American Physical Society (APS) Division of Particles and Fields has given its 2019 Early Career Instrumentation Award to two scientists on the international Deep Underground Neutrino Experiment (DUNE), hosted by Fermilab.

You can read this brief article at the Fermilab News website.

A neutrino candidate event selected by this analysis is shown as a bird’s-eye view of the MicroBooNE detector. In this view, neutrinos arrive from the left. The five prongs show five particles that have been produced by a neutrino interaction with an argon atom. The longest prong is the candidate muon, going backwards with respect to the neutrino direction.

The most recent physics result from the MicroBooNE experiment provides one of the very first rigorous tests of our understanding of neutrino interactions with argon. The paper, published in Physical Review Letters, presents the first ever measurement of neutrino interactions on argon as a function of the momentum and angle of the muon, a particle produced in the interaction (technically called a “double-differential cross section measurement”).

By Anne Schukraft and Marco Del Tutto. You can read the article here.

Photomultiplier tubes dot the 26-ton water tank of ANNIE, the Accelerator Neutrino Neutron Interaction Experiment. Photo: Reidar Hahn, Fermilab

The inside of the ANNIE detector looks like a series of carefully placed Jell-O domes, or perhaps a jeweled Fabergé egg. Its walls are dotted by 137 sensors for detecting packets of light and embrace 26 tons of gadolinium-doped water.

By Catherine N. Steffel. Read the entire article here.

As the ADMX detector is removed from its magnet, the liquid helium used to cool the experiment forms vapor. Photo: Rakshya Khatiwada

In 2017, ADMX operated with the highest sensitivity of any axion experiment to date. In doing so, it ruled out a range of possible axion masses.

Now the ADMX collaboration released its latest results based on data taken in 2018. The new results rule out yet another mass range, four times wider than the first, while maintaining the same degree of exceptional sensitivity.

By Caitlyn Buongiorno. You can read this article at the Fermilab News web site.

Among the Fermilab Quantum Institute’s suite of programs is a project to look for direct evidence of dark matter. Photo: Reidar Hahn

Today the U.S. Department of Energy’s Fermi National Accelerator Laboratory announced the launch of the Fermilab Quantum Institute, which will bring all of the lab’s quantum science projects under one umbrella. This new enterprise signals Fermilab’s commitment to this burgeoning field, working alongside scientific institutions and industry partners from around the world.

This press release can be read from the Fermilab News web site.

Recent measurements at the Fermilab Booster accelerator confirmed existence of a certain kind of particle beam instability. More measurements are planned for the near future to examine new methods proposed to mitigate it.

Accelerated, charged particle beams do what light does for microscopes: illuminate matter. The more intense the beams, the more easily scientists can examine the object they are looking at. But intensity comes with a cost: the more intense the beams, the more they become prone to instabilities.

By Alexey Burov . You can read the entire article at the Fermilab News web site.