High Energy

Search for boosted Higgs advances our understanding of dark matter

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This story, featuring physics graduate student Shivani Lomte, was originally published by the CMS collaboration

The CMS Collaboration hunts for Higgs bosons recoiling against dark matter particles

Shivani Lomte

Dark matter is one of the most perplexing mysteries of our universe, accounting for roughly 27% of its total energy. Dark matter does not emit, absorb, or reflect light, and is thus invisible to telescopes. However, its effects on gravitation are unmistakable. Although dark matter’s elementary nature remains unknown, scientists hypothesize that it might be made up of weakly interacting massive particles (WIMPs) that rarely interact with ordinary matter.

In the CMS experiment, we use the fundamental law of momentum conservation to infer the possible presence of dark matter in the detector. In particular the momentum in the transverse plane should be conserved before and after the proton-proton (pp) collision – in other words, the sum of all particle momenta combined should balance out. If momentum is missing, then this suggests that an ‘invisible’ particle, for instance a dark matter particle, has carried that momentum away. Since dark matter doesn’t interact with the detectors, we can’t directly observe it. To detect its presence, we use a ‘visible’ known particle that recoils against the dark matter particle, providing a detectable signal in the experiment. An example of this type of process is shown in Fig. 1.

Figure 1: An event display from the transverse plane which illustrates a signal-like event: the orange cone corresponds to a jet that recoils against missing transverse energy, represented as a magenta arrow. | Credit: CMS collaboration

In pp collisions, a photon, ‘jet’, W or Z boson can be emitted from the initial quark within the proton, whereas radiating a Higgs boson is extremely rare given its small coupling to the quarks. Higgs bosons might be preferentially emitted through a new particle acting as a ‘mediator’ between the standard model and dark matter sector. There is a unique possibility at LHC to produce the mediator particle and study its interaction with the standard model and dark matter.

This analysis uses the “mono-Higgs” signature to search for dark matter particles, focusing on two scenarios that both involve Higgs bosons decaying to bottom quarks. If the Higgs boson is highly energetic (boosted), its decay products become collimated and can be reconstructed in a single large-radius ‘jet’. Alternatively, if the Higgs is not as energetic, we instead look for two small-radius jets, one from each bottom quark. The two scenarios are illustrated in Fig. 2.

Schematic depiction of the “mono-Higgs” → bb̄ production process. On the left, the Higgs decay products merge into a large-radius jet. On the right, the Higgs decay products are reconstructed as two small-radius jets
Figure 2: Schematic depiction of the “mono-Higgs” → bb̄ production process. On the left, the Higgs decay products merge into a large-radius jet. On the right, the Higgs decay products are reconstructed as two small-radius jets. | Credit: CMS collaboration

“A key challenge in this search is that the dark matter signal is rare (at best) and well-known processes, as described in the standard model, produce very similar signatures. To reduce the backgrounds from known particles, we use distinguishing features like the momentum and energy distribution of the particles” says Shivani Lomte, a graduate student at the University of Wisconsin-Madison, leading this search. The precise estimation of the background is critical and is achieved using so called control regions in the data. Such control regions are dominated by background processes and this allows us to quantify the amount of backgrounds in the signal region where we search for dark matter.

In this analysis, once the backgrounds were well-understood, we looked for the dark matter signal by comparing the observed data distributions to the predicted backgrounds, looking for discrepancies. Unfortunately, the observed data agrees with the standard model predictions, and so we conclude that our result has no sign of dark matter. We can thus rule out those types of dark matter particles that would have been detected if they existed.

Regardless of the outcome, the search for dark matter is a journey that pushes the boundaries of human knowledge. Each step brings us closer to answering some of the most profound questions about the nature of the universe and our place within it.

Dark matter and pencil jets: The search for a low-mass Z’ boson using machine learning

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a neon-colored drawing of a burst of yellow lines in a cylinder with a line transversing the centerof the cylinder with "pencil jet" on the blunt end and "missing transverse momentum" on the arrow side

This story, featuring physics grad student Abhishikth Mallampalli, was originally published by the CMS collaboration

The CMS experiment conducts the first search for dark matter particles produced in association with an energetic narrow jet—the pencil jet.

Dark matter remains one of physics’ greatest mysteries. Despite making up about 27% of the universe’s energy content, its true nature is unknown. Astonishingly, all ordinary matter—which includes stars, planets, our phones, the wires transferring data, the waves carrying WiFi, you and me—accounts for just 5% of the total energy content of our universe. If our known world is so diverse, the dark sector, which outweighs it 20-to-1, could be just as rich. At CERN’s CMS experiment, scientists are searching for dark matter particles, aiming to reveal their interactions and revolutionize our understanding of our universe.

But if dark matter is so abundant, why haven’t we detected it? As the name suggests, dark matter does not interact with light (electromagnetism) with the same strength as ordinary matter (the behavior of which is explained by the Standard Model) and, so far, is only known to interact with known particles through gravity, the weakest of the four known fundamental forces. At CMS, scientists use momentum conservation to infer the presence of dark matter: missing momentum in particle collisions (after accounting for detector mismeasurements) could signal an invisible particle, possibly dark matter, slipping away undetected.

In addition to particles that make up dark matter, there could be as yet undetected particles that mediate interactions between the dark particles and the matter particles. These are creatively called, you guessed it, mediators. Such mediators are bosons, implying that they carry integer spin quantum numbers as opposed to fermions (e.g. electrons) which have half-integer spins. One such mediator is the hypothesized Z’ boson, which is electrically neutral and has spin quantum number of 1.

Typical CMS searches focus on heavy Z’ particles in the hundreds of GeV to TeV range, but a lighter Z’ boson could also exist in the dark sector. It is typically a lot more challenging to look for such light particles due to the overwhelming background from hadronic resonances and quantum chromodynamics (QCD) processes—related to the strong nuclear force—which are poorly modeled at low energies. This is where techniques like data augmentation and machine learning can be utilized, enhancing sensitivity to Z’ decays while suppressing known background processes.

The Z’ boson mass that we are looking for in this search is around 1 GeV, and because of the low mass and high boost (momentum) of the Z’ boson, it can only decay to light quarks (u, d, s), which then hadronize to form a jet (a spray of particles) with a lower number of constituents than usual. We then look for dark matter recoiling against such a narrow jet (called a pencil jet). This is the first search at the LHC for this signal. Various selections are applied to reduce the background processes while retaining the signal process and a combination of neural networks and boosted decision trees are used to further extract the signal. Multiprocessing techniques are used to speed up the processing time of the events.

“The main challenge in this analysis of real-world data was that the physically motivated input features aren’t typically well modeled in our simulations and so we had to take steps to ensure model robustness. We showed that using machine learning can help us achieve up to 10 times more sensitivity to these rare signal processes compared to traditional strategies” says Abhishikth Mallampalli, a graduate student at the University of Wisconsin-Madison, leading this search. Statistical hypothesis testing is used to determine whether the observed data agrees with the standard model prediction or suggests the presence of a dark matter signal.

We see that the data agrees well with the standard model expectation across the three years of proton-proton collision data analyzed. While this means that such a Z’ boson with the probed light masses might not exist in our universe at the 95% confidence level, null results in such searches for dark matter not only solidify the standard model but also serve as guidance to theorists in building new physics models for dark matter, and help experimentalists to identify the direction for future searches.

UW–Madison scientists part of team awarded Breakthrough Prize in Physics

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hundreds if not thousands of people stand in front of the CMS detector

A team of 13,508 scientists, including over 100 from the University of Wisconsin–Madison, won the 2025 Breakthrough Prize in Fundamental Physics, the Breakthrough Prize Foundation announced April 5. The Prize recognized work conducted at CERN’s Large Hadron Collider (LHC) between 2015 and 2024.

The Breakthrough Prize was created to celebrate the wonders of our scientific age. The $3 million prize will be donated to the CERN & Society Foundation, which offers financial support to doctoral students to conduct research at CERN.

Four LHC projects were awarded, including ATLAS and CMS, both of which UW–Madison scientists work on. ATLAS and CMS jointly announced the discovery of the Higgs boson in 2012, and its discovery opened up many new avenues of research. In the years since, LHC researchers have worked towards a better understanding of this important particle because it interacts with all matter and gives other particles their mass. Both teams are actively engaged in analyzing LHC data in search of exciting and new physics.

“The LHC experiments have produced more than 3000 combined papers covering studies of electroweak physics and the Higgs boson, searches for dark matter, understanding quantum chromodynamics, and studying the symmetries of fundamental physics,” says CMS researcher Kevin Black, chair of the UW–Madison department of physics. “This work represents the combined contributions of many thousands of physicists, engineers, and computer scientists, and has taken decades to come to fruition. We are all very excited to be recognized with this award.”

thousands of people stand as a group in front of some vaguely science-y looking (and very large!) equipment
Over 13,000 LHC researchers were awarded the 2025 Breakthrough Prize, including a subset of the ATLAS team seen here. | Source: CERN

ATLAS and CMS have generally the same research goals, but different technical ways of addressing them. Both detectors probe the aftermath of particle collisions at the LHC and use the detectors’ high-precision measurements to address questions about the Standard Model of particle physics, the building blocks of matter and dark matter, exotic particles, extra dimensions, supersymmetry, and more.

The ATLAS team at UW–Madison has taken a leadership role in both physics analyses and computing. They have spearheaded precision measurements of the Higgs boson’s properties and conducted extensive searches for new physics, including Dark Matter, achieving major sensitivity gains through advanced AI and machine learning techniques. In addition to leading developments in computing infrastructure, the team has played a crucial role in the High-Level Trigger system and simulation efforts using generative AI, further enhancing the experiment’s capabilities.

The CMS team at UW–Madison has played and continues to play key roles in trigger electronics systems, which are ways of sorting through the tens of millions of megabytes of data produced each second by a collider experiment and retaining the most meaningful events. They also manage a large computing cluster at UW-Madison, contribute to the building and operating of muon detectors, make key contributions to CMS trigger and computing operations, and develop physics analysis techniques including AI/ML. The CMS group efforts are well recognized in the recently published compendium of results, dubbed, the Stairway to Heaven.

CMS and ATLAS research at UW–Madison is largely supported by the U.S. Department of Energy, with additional support from the National Science Foundation.

The following people had a UW–Madison affiliation during the time noted by the Prize:

Current Professors

Kevin Black, Tulika Bose, Kyle Cranmer, Sridhara Dasu, Matthew Herndon, Sau Lan Wu

Current PhD Physicists

Pieter Everaerts, Matthew Feickert, Camilla Galloni, Alexander Held, Wasikul Islam, Charis Koraka, Abdollah Mohammadi, Ajit Mohapatra, Laurent Pétré, Deborah Pinna, Jay Sandesara, Alexandre Savin, Varun Sharma, Werner Wiedenmann

Current Graduate Students

Anagha Aravind, Alkaid Cheng, He He, Abhishikth Mallampalli, Susmita Mondal, Ganesh Parida, Minh Tuan Pham, Dylan Teague, Abigail Warden

Current Engineering Staff

Shaojun Sun

Current Emeriti

Sunanda Banerjee (Senior Scientist), Richard Loveless (Distinguished Senior Scientist),  Wesley H. Smith (Professor)

Alumni

Michalis Bachtis (Ph.D. 2012), Swagato Banerjee (Postdoc 2015), Austin Belknap (Ph.D. 2015), James Buchanan (Ph.D. 2019), Cecile Caillol (Postdoc), Duncan Carlsmith (Professor), Maria Cepeda (Postdoc), Jay Chan (Ph.D. 2023), Stephane Cooperstein (B.S. 2014), Isabelle De Bruyn (Scientist), Senka Djuric (Postdoc), Laura Dodd (Ph.D. 2018), Keegan Downham (B.S. 2020), Evan Friis (Postdoc), Bhawna Gomber (Postdoc), Lindsey Gray (Ph.D. 2012), Monika Grothe (Scientist), Wen Guan (Engineer with PhD 2022), Andrew Straiton Hard (Ph.D. 2018), Yang Heng (Ph.D. 2019), Usama Hussain (Ph.D. 2020), Haoshuang Ji (Ph.D. 2019), Xiangyang Ju (Ph.D. 2018), Laser Seymour Kaplan (Ph.D. 2019), Lashkar Kashif (Postdoc 2019), Pamela Klabbers (Scientist), Evan Koenig (BS 2018, Intern), Amanda Kaitlyn Kruse (Ph.D. 2015), Armando Lanaro (Senior Scientist), Jessica Leonard (Ph.D. 2011), Aaron Levine (Ph.D. 2016), Andrew Loeliger (Ph.D. 2022), Kenneth Long (Ph.D. 2019), Jithin Madhusudanan Sreekala (Ph.D. 2022) Yao Ming (Ph.D. 2018), Isobel Ojalvo (Ph.D. 2014, Postdoc), Lauren Melissa Osojnak (Ph.D. 2020), Tom Perry (Ph.D. 2016), Elois Petruska (BS, 2021), Yan Qian (Undergraduate Student 2023), Tyler Ruggles (Ph.D. 2018, Postdoc), Tapas Sarangi (Scientist), Victor Shang (Ph.D. 2024), Manuel Silva (Ph.D. 2019), Nick Smith (Ph.D. 2018), Amy Tee (Postdoc, 2023), Stephen Trembath-Reichert (M.S. 2020),  Ho-Fung Tsoi (Ph.D. 2024), Devin Taylor (Ph.D. 2017), Wren Vetens (Ph.D. 2024), Alex Zeng Wang (Ph.D. 2023), Fuquan Wang (Ph.D. 2019), Nate Woods (Ph.D. 2017), Hongtao Yang (Ph.D. 2016), Fangzhou Zhang (Ph.D. 2018), Rui Zhang (Postdoc, 2025), Chen Zhou (Postdoc 2021)

NOvA study sets tighter limit on sterile neutrinos

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Neutrinos have always been difficult to study because their small mass and neutral charge make them especially elusive. Scientists have made a lot of headway in the field and can now detect three flavors, or oscillation states, of neutrinos. Other flavors continue to be elusive — though that could be because they don’t even exist.

Sterile neutrinos, a flavor that has been proposed to play a role in neutrino mass generation and causing the oscillations of other neutrinos, have been hinted at in previous experiments but never detected. In a study published February 26 in Physical Review Letters, NOvA collaboration scientists did not find evidence of sterile neutrinos, but their work puts the tightest constraints on parameter space to date for where sterile neutrinos could be found. 

“Neutrinos are really interesting because they can give a window into some really big questions for physics, including the question of the matter-antimatter asymmetry and why the universe exists at all,” says co-lead author Adam Lister, a postdoctoral researcher in physics professor Brian Rebel’s group at the University of Wisconsin–Madison and member of the NOvA collaboration. “It turns out you can get at these questions with neutrino oscillations, and in this paper, we tried to address the question of, ‘What if there are more types of neutrinos that we haven’t yet been able to observe?’”

two 3-d plots depicting a neutrino detection at the far detector. On the left, the detections show a scatter of light, on the right, the detections show a long, single trace (wtih a small amount of scatter near the entry point)
Depictions of particle traces at the far detector. In both images, the beam enters from the left and moves through the detector. When a neutrino interacts in the detector, it can produce a number of charged particles, which produce light as they travel through the detector. The light is recorded, and shown here as points. Based on the light pattern, the researchers use a neural network to classify an event as a neutral current interaction (left panel) with a characteristic shower of particles or as a charged current interaction (right), with a characteristic long track. | Provided by Adam LIster

Sterile neutrinos have been proposed for a couple of decades, when previous experiments showed results that could best be explained by the existence of a fourth (or greater) flavor of neutrino. 

“There are a number of experiments that claim that they see something consistent with this new neutrino, and there’s a bunch of other experiments that have looked for those same neutrinos and seen nothing whatsoever,” Lister says. “It’s a very open question right now.”

Profile picture of Adam Lister
Adam Lister
profile photo of Harry Hausner
Harry Hausner
profile photo of Brian Rebel
Brian Rebel

To search for sterile neutrinos, the NOvA experiment produces a beam of one flavor of neutrino, muon neutrinos, at Fermilab and directs it toward two detectors: a near detector about one kilometer from the beam source, and a far detector around 800 kilometers away in Ash River, MN. Previous NOvA analyses measured only the neutral current disappearance rate, where any of the three flavors of neutrinos converts to another particle when it interacts with a detector. So in this new study, the researchers knew that if they observe an unexpected change in the total number of neutrinos, it suggests that sterile neutrinos did in fact influence the other types. 

Earlier NOvA work only measured this rate at the far detector, because it was the best developed analysis strategy available at the time. However, it assumed that sterile neutrinos could not influence the other neutrinos in the first kilometer. Here, the team used updated software and improved simulations to analyze neutral current rate changes at both near and far detectors, but these results did not deviate from the expected three-flavor model.

a graph of reconstructed neutrino energy on the x-axis and number of events in a given range of energy on the y-axis.
The number of times a neutrino of a given energy range (x axis) was counted (y axis) at the far detector, shown as data points. The shaded grey area shows where the data should fit if the three-flavor (i.e. no sterile neutrinos) model is true, and overall there are no deviations from this model. The dark shaded area at the bottom shows counts due to cosmic rays. | From this study

Second, they introduced an additional sample, known as muon neutrino charged current interactions, or the disappearance specifically of muon neutrinos at both the near and far detectors. Small changes from the expected rate could also indicate the influence of sterile neutrinos, but again, they did not observe a statistically significant rate difference.

Combined with the fact that the team applied their analyses to six years of cumulative data — all the data of previous NOvA analyses plus newer data — this new study offers NOvA’s most powerful analysis of sterile neutrino physics to date. Though the study could not confirm the existence of sterile neutrinos, NOvA scientists were able to search the four different samples together simultaneously, allowing them to rule out certain parameter combinations that are physically incompatible with sterile neutrinos.

“Our results agree with the standard three-flavor oscillation model, at least with the statistical uncertainties we have,” Lister says. “What we can say right now is that NOvA sets some of the strongest limits on the existence of the sterile neutrinos.”

The NOvA experiment could not confirm the existence of the sterile neutrino. IceCube, led by UW–Madison, performs complementary searches using atmospheric and astrophysical neutrinos and has also not found any evidence for sterile neutrinos.

These results are also critical to informing the analyses of the next-gen accelerator-based neutrino detector, DUNE, which Lister and colleagues at UW–Madison are already developing. 

This study was published by the NOvA collaboration, centered at Fermilab, and largely led by scientists at UW–Madison (Lister, Rebel, and former graduate student Harry Hausner) and the University of Cincinnati (postdoctoral researcher V. Hewes and physics professor Adam Aurisano). 

This work was supported by the U.S. Department of Energy; the U.S. National Science Foundation; the Department of Science and Technology, India; the European Research Council; the MSMT CR, GA UK, Czech Republic; the RAS, MSHE, and RFBR, Russia; CNPq and FAPEG, Brazil; UKRI, STFC and the Royal Society, United Kingdom; and the state and University of Minnesota. 

 

Welcome, Prof. Jakob Moritz!

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String theorist Jakob Moritz joined the faculty as an assistant professor of physics on January 1, 2025. He joins us from CERN where he has been a postdoc for just over a year. Previously, he was a postdoc for four years at Cornell University, and before that, he earned his PhD from the University of Hamburg and DESY.

Please give a general overview of your research.

I work on string theory, a theoretical framework for quantum gravity. It is the only known approach that consistently combines quantum mechanics and Einstein’s theory of gravity. Physicists have struggled for decades to reconcile these two fundamental theories, and string theory achieves this unification. Sometimes called “the theory of everything,” string theory addresses physical phenomena at arbitrarily high energies. While the nickname may sound a bit grandiose, it highlights the theory’s incredible scope.

However, while the field equations of string theory have solutions that are relatively easy to study, these don’t resemble our universe. My research focuses on going beyond these “easy” solutions to find ones that better match the universe we observe. By doing so, I aim to uncover insights into the origins of the peculiar laws of physics governing our universe.

Something that I find particularly interesting is dimensionless constants of nature. These constants are significant because they are independent of a choice of units. For example, the ratio of the electron’s mass to the top quark’s mass is a dimensionless number — about 0.000003, which is remarkably small! There are many such constants whose values are determined experimentally, yet we lack a theoretical explanation for them.

In the early 20th century, particle physicists didn’t focus much on questions like, “Why are the constants of nature what they are, and not something else?” But with string theory, we can begin to address this. My work seeks to identify solutions of string theory in which these numbers align with experimental values. Another well-known example is the energy density of the vacuum, or dark energy. Despite being the dominant energy source in the universe today, dark energy is extraordinarily small in natural units — just 10^{-120} when compared to the natural energy scale of quantum gravity. This discrepancy, known as the cosmological constant problem, is something I find deeply intriguing. How can such a small value arise? Why isn’t it zero? Similarly, why is the Higgs mass so small? These are the kinds of profound questions I aim to explore through string theory.

What are one or two main projects you’ll have new group members work on?

One major project will involve finding the Standard Model of particle physics within string theory. This is something I am already working on, but having more hands on deck would be invaluable. The goal is to “engineer” realistic laws of particle physics — either the Standard Model or something close to it — as solutions of string theory. This work is crucial for addressing the electroweak hierarchy problem: why is the Higgs mass so unnaturally small? Currently, no one has a clear explanation for this.

Technically, this involves a lot of geometry. String theory predicts the existence of extra dimensions, which are both a blessing and a curse. They must be small enough to have remained unobservable, yet they also determine the physical laws we experience at larger scales. Much of our work will focus on understanding these geometries — particularly how certain objects, called branes, wrap around features like circles in these spaces — and calculating the resulting physical laws.

What attracted you to Madison and the university?

I really appreciate the breadth of the theory department here. String theory is a vast field, encompassing topics that range from almost pure mathematics to particle phenomenology. Because my work leans toward the phenomenological side, it intersects with many other areas of theoretical physics, including cosmology, particle physics, and applied mathematics. Being at a large place like Madison, with its diverse and talented faculty, is incredibly exciting.

Additionally, I know that Madison attracts outstanding students who are eager to work on string theory and particle physics. That’s something I’m looking forward to as well!

What is your favorite element and or elementary particle?

Neutrinos are cool because they’re almost massless. For a long time, they were thought to have zero mass, as predicted by the Standard Model of particle physics. But experiment has revealed otherwise! This discovery hints strongly at new physics at high energies.

What hobbies and interests do you have?

I love music! I play piano and guitar, and music is a big part of my life, especially since my partner is also a musician. I also enjoy sailing. While at Cornell, I spent summers sailing and participated in weekly competitive races, which were incredibly fun. I know that sailing is also a thing here — I look forward to getting back on the water!

New NOvA results add to mystery of neutrinos

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The international NOvA collaboration presented new results at the Neutrino 2024 conference in Milan, Italy, on June 17. The collaboration doubled their neutrino data since their previous release four years ago, including adding a new low-energy sample of electron neutrinos. The new results are consistent with previous NOvA results, but with improved precision. The data favor the “normal” ordering of neutrino masses more strongly than before, but ambiguity remains around the neutrino’s oscillation properties.

At UW–Madison, the NOvA collaboration includes physics professor Brian Rebel, postdoc Adam Lister, former postdoc Tom Carroll, and grad student Anna Cooleybeck.

The latest NOvA data provide a very precise measurement of the bigger splitting between the squared neutrino masses and slightly favor the normal mass ordering. That precision on the mass splitting means that, when coupled with data from other experiments performed at nuclear reactors, the data favor the normal ordering at almost 7:1 odds. This suggests that neutrinos adhere to the normal ordering, but physicists have not met the high threshold of certainty required to declare a discovery.

Read the full story, originally published by Fermilab

Two physics students win presentation awards at APS April Meeting

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Elias Mettner and Nadia Talbi, both conducting research in high energy physics at UW–Madison, won undergraduate presenter awards at the American Physical Society’s April Meeting.

The meeting, held in Sacramento April 3-6, included seven undergraduate oral presentation sessions with six to eight students in each session. The top two students from each session earned “Top Presenter” awards. Mettner and Talbi were the only two UW–Madison students who gave oral presentations, and both won awards.

profile photo of Elias Mettner
Elias Mettner

Mettner is a physics major working with scientist Abdollah Mohammadi. His talk was titled “Pair Production and Hadron Photoproduction Backgrounds at the Cool Copper Collider.”

The Cool Copper Collider is a proposed electron-positron collider that will help scientists to explore the Higgs boson even further. The electron-positron beam will have some natural decay that converts into particles and is recorded by the detector. Mettner’s research asks how this beam background will impact the detector.

“The detector will record this background, and it could take the place of the data we want or make it harder to reconstruct data,” Mettner says. “It’s important to make sure that the backgrounds that will come into the detector using this new design will not cause any issues, otherwise the benefits of this collider design cannot be put to their maximum use.”

Mettner had been interested in physics from a young age and comes from a family of teachers who encouraged him to explore his academic interests. Upon entering UW–Madison, he jumped at the chance to conduct research in particle physics. He joined the UW CMS Collaboration in his freshman year through the Undergraduate Research Scholars program and began his project with the Cool Copper Collider soon after. He was also awarded the Sophomore Research Fellowship for his junior year and the Hilldale Research Fellowship for his upcoming senior year.

a woman stands in front of a screen with a powerpoint presentation title slide showing
Nadia Talbi presents at APS April Meeting

Talbi is an astronomy-physics major working in physics professor Tulika Bose’s group and mentored by postdoc Charis Koraka. Her talk, “A Search for Vector-Like Leptons: Compact Analysis,” covered work she has done through a Thaxton Fellowship.

“Bosons are force particles, and basically every boson except for the Higgs — the photon, the gluon — is a vector boson. Leptons are electrons, muons, neutrinos, stuff like that,” Talbi explains. “Vector-like leptons are a hypothetical particle, we don’t know whether or not they exist.”

Talbi was drawn to astronomy because she has long had an interest in the fundamental nature of the universe. As a child, she read an article on Dark Matter and, later, a friend gave her a book on the Standard Model. She was hooked. When she applied for the Thaxton Fellowship, a departmental program that was started to provide more equitable access to undergraduate research in physics, she discussed her interest in particle physics and the research at CERN, which landed her in Bose’s group.

“So before I even had any formal education in physics, where things can be very black and white, I’ve had the opportunity to understand the beautiful things within the field,” Talbi says. “Studying physics, I think, gives you some of the most fundamental understanding of our existence.”

Both Metter and Talbi say that attending conference was overall a very worthwhile experience — even if they both had to take an E+M exam remotely before presenting. (“It was a good bonding experience,” Talbi says.)

“The conference was a lot of fun, and worth it to go and make some connections and experience a bunch of really interesting research from people all in different stages of their careers,” Mettner says.

Adds Talbi: “There were so many undergraduates there, I met so many, I made a lot of friends. It felt like there was a community.”

Both students were also invited to present their award-winning talks to the Physics Board of Visitors spring meeting.

Tulika Bose honored with Vilas Distinguished Achievement Professorship

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Vilas Distinguished Achievement Professor Tulika Bose

Sixteen professors, including physics professor Tulika Bose, were named to Vilas Distinguished Achievement Professorships, an award recognizing distinguished scholarship as well as standout efforts in teaching and service. The professorship provides five years of flexible funding — two-thirds of which is provided by the Office of the Provost through the generosity of the Vilas trustees and one-third provided by the school or college whose dean nominated the winner. The awards are supported by the estate of professor, U.S. Senator and UW Regent William F. Vilas (1840-1908).