Priscilla Pani, a scientist in the ATLAS group at DESY, has been awarded a European Research Council Starting Grant for a new method of searching for new particles. She will use the ATLAS experiment at the Large Hadron Collider at CERN in Geneva to pick up hints of new light particles that may interact with more massive versions of some of the constituent particles of matter. The grant, worth 1.5 million euro in a project that will last five years, will allow Pani to build her own working group on the subject on the Zeuthen campus.

Pani’s work relates to the ability to detect relatively light particles that decay to bottom quarks, heavier versions of the constituent particles of protons and neutrons, the quarks. The decays of bottom quarks are fairly frequent in LHC collisions. Fishing out signals that might be interesting is the biggest challenge of the project. “This new method will hopefully have the sensitivity to pick up very light particles and how they interact with these quarks,” Pani says.

In particular, Pani is looking for a signal called a double b-jet resonance. B-jets are showers of energetic particles that contain B-mesons, a type of complex particle containing a bottom quark. However, the b-jets are extremely frequently observed in ATLAS particle reconstructions, meaning that the particular ones that she wants to see could be like finding a needle in an entire barn full of hay.

“What I proposed in this grant is that we look at b-jets in a set of rare channels that can be triggered by the current ATLAS system,” she says. The triggers would be a signal that would activate the uptake of data instantaneously. The signal she proposes would show a b-jet that also contains another particle called a J-Psi. “This makes the reading of these signals five to ten times more efficient and provides new insights into the existence of new light particles,” she says.

These particles could in turn represent a new force that would bridge known particles with dark matter. “The most important thing though, is that this method is model-agnostic, so it can explore many different scenarios at the same time,” Pani says. “We have already performed a first exploration of LHC data so it is important, as we move forward to have new methods that are independent of a specific set of models.”

The Starting Grant goes into effect on 1 May. It will help Pani establish a new group to develop her research.

“I am delighted that Priscilla Pani's project has been funded by the ERC,” says DESY Director for Particle Physics Beate Heinemann. “Her brilliant novel idea on how to search for new particles that decay to b-quarks at the LHC will ensure that the data from the LHC are fully exploited, and has the potential to make a groundbreaking discovery.”