Lunchtime Seminars


Seminar Details

Tuesdays 12:00 PM

All seminars are hybrid
Building 26, 414 (Kolker Room)


Committee: Ronald Garcia Ruiz ~ Michael Williams ~ Prajwal MohanMurthy

Spring 2024



Seb Jones  

The QTNM collaboration: a project for absolute neutrino mass measurement

The observation of neutrino oscillations provides proof of non-zero neutrino masses, something which was not predicted in the minimal Standard Model. However, these same neutrino oscillation experiments do not provide information on the absolute scale of the neutrino masses, which remain unknown. The neutrino masses are most directly accessed through those experiments which measure the shape of the beta-decay energy spectrum. In particular, a technique known as Cyclotron Radiation Emission Spectroscopy (CRES) offers the opportunity to measure neutrino masses lower than the current upper mass limit of 0.8 eV achieved by the KATRIN collaboration. The Quantum Technologies for Neutrino Mass (QTNM) collaboration aims to utilise CRES, along with recent breakthroughs in quantum technologies, to build a demonstrator apparatus for measuring the neutrino mass. It is hoped that this demonstrator will make significant contributions towards an experiment with a neutrino mass sensitivity of O(10 meV). I will present an overview of the principles of neutrino mass measurement as well as the QTNM collaboration



No Talk - Rescheduled





Gianfranco Bertone  

Gravitational wave probes of dark matter  

I will start with an overview of the status of dark matter searches and of the prospects for uncovering its nature in the next decade. I will then focus on the interplay between dark matter, black holes, and gravitational waves, and discuss the prospects for characterizing and identifying dark matter using gravitational waves, covering a wide range of candidates and signals. Finally, I will present some new results on the detectability of dark matter overdensities around black holes in binary systems, and argue that future interferometers may enable precision studies of the dark matter distribution and particle properties.



Silviu Udresu

Precision spectroscopy studies of radioactive molecules for fundamental physics

Molecules are unique quantum systems for fundamental physics studies. Possessing a large sensitivity to nuclear effects and violations of the fundamental symmetries of nature, they can enable precision tests of the Standard Model and the possibility to probe energy scales beyond tens of TeV. Molecules containing octupole-deformed nuclei, such as radium monofluoride (RaF), are expected to be particularly sensitive to symmetry violating nuclear properties. In this talk, I will present the results obtained from a series of laser spectroscopy experiments performed on short-lived RaF molecules at the ISOLDE facility at CERN. The vibrational structure of (223-226,228)RaF and the rotational and hyperfine structure of 226RaF and 225RaF were measured with high precision. This allowed us to establish a laser cooling scheme for these molecules and to investigate the effects of electroweak nuclear properties on the molecular energy levels. These results are the first of their kind performed on radioactive, short-lived molecules, opening the way for future precision studies and new physics searches in these systems. I will then discuss the current status of a novel experiment aiming to measure hadronic parity violation using molecular ions inside a Penning trap. Our method should allow measurements over the entire nuclear chart, providing enhancements in the sensitivity to the sought for signals of more than 12 orders of magnitude compared to atoms. Finally, I will present the developments of a highly sensitive experimental setup for precision laser spectroscopy studies of very short-lived isotopes (lifetime < 1 ms), produced in small amounts (< 1/minute) in hot environments, without the need for cooling techniques. Such nuclear systems are of paramount importance to guide our understanding of nuclear matter and connect our description of nuclei with the underlying theory of the strong force.



Marta Babicz  

Probing the Secrets of Matter Creation with LEGEND

The LEGEND experiment seeks to detect lepton-number violation and shed light on neutrino masses by hunting for neutrinoless double beta decay. The experiment employs high-purity germanium detectors enriched in $^{76}$Ge and an active liquid-argon shield to minimize background events. In its initial phase, utilizing ~200 kg of germanium crystals, LEGEND targets a half-life discovery sensitivity of 10$^{27}$ years. The cosmic quest continues in the second phase, deploying ~1000 kg of detectors to push the discovery sensitivity beyond 10$^{28}$ years. Renowned for its superior energy resolution and ultra-low background levels, LEGEND promises a quasi-background-free search, unveiling an unambiguous signature at the 2039 keV decay Q-value. Join us on this journey as LEGEND ventures into the depths of neutrino exploration, pushing the boundaries of discovery and expanding our understanding of the universe. In this presentation, I will explain the importance of 0νββ to the fields of neutrino and beyond the Standard Model physics, as well as discuss the current status and the plans of the LEGEND-200 and the LEGEND-1000 experiments, respectively.



Dimitrii Krasnopevtsev

Identification of cosmic-ray positrons and electrons at TeV energy scale with the Alpha Magnetic Spectrometer

The Alpha Magnetic Spectrometer (AMS) is a general purpose high energy particle detector, which was successfully deployed on the International Space Station on May 19, 2011. It conducts a unique, long-duration mission of fundamental physics research in space. To date, the detector has collected over 220 billion cosmic ray events. One of the main AMS objectives is the measurement of cosmic ray elementary particles. I will present new techniques for the identification of electrons and positrons, which are used in the AMS data analysis up to the energies of few Tera-electronvolts. These techniques allowed to reveal unique properties of particle fluxes and indicate the existence of a primary source of high-energy electrons and positrons, associated with either Dark Matter or Astrophysical origin. AMS is poised to continue its mission through 2030, providing unique insights into the origins of cosmic ray matter and antimatter and exploring new physics phenomena within the cosmos.




Gregor Eberwin

ALICE ITS3: Road to a vertex detector based on bent, wafer-scale, monolithic active pixel sensors

The innermost three layers of the inner tracker currently installed in ALICE will be replaced by the ITS3 during the Long Shutdown 3 (LS3) of the LHC (2026-2028). The ITS3 is based on wafer-scale, cylindrically bent Monolithic Active Pixel Sensors (MAPS) with a thickness below 50 μm. Stitching is used to manufacture sensors of up to 26 x 9.4 cm2 size in 65 nm CMOS technology. The ITS3 will be constructed as two half barrels with three sensors each, at radii of 18, 24, 30 mm from the beam axis, respectively. The air-cooled sensors are held in place with carbon foam, allowing for an extremely low material budget with an unprecedented 0.05% X/X0 per layer. Together with the reduction of tracking layer distance to the interaction point (24 mm to 18 mm for the innermost layer), this leads to a 2x improvement in impact parameter resolution for transverse momenta between ~0.1-10 GeV/c compared to the current detector. The prototype MOnolithic Stitched Sensor MOSS has been designed and manufactured to demonstrate the feasibility of the stitching process, and testing started summer 2023. A single MOSS chip has dimensions of 14 x 259 mm2 and 6.72 million pixels. To characterize the MOSS chip, a dedicated test system has been developed, and will be presented together with the first results of the measurement campaign.




No Talk - Spring Break




Michael Doser

Pulsed production of antihydrogen and other antiprotonic systems for precisions tests of fundamental symmetries

The production of cold antihydrogen atoms at CERN's Antiproton Decelerator (AD) has opened up the possibility to perform direct measurements of the Earth's gravitational acceleration on antimatter bodies. This is the main goal of the AEgIS collaboration: to measure the value of g using a pulsed source of cold horizontally travelling antihydrogen via a moiré deflectometer/Talbot-Lau interferometer. The first milestone of pulsed production of antihydrogen [1] using a resonant charge-exchange reaction between cold trapped antiprotons and Rydberg positronium (or Ps, the atomic bound state of a positron and an electron) atoms, and the techniques it relies on, will be presented, with a view to the first gravitational experiments using a pulsed beam of antihydrogen in the near future. Further physics directions in AEgIS relying on similar pulsed interactions in positronium [2] or between antiprotons and Rydberg atoms and molecules will also be touched upon, as they open up unexplored venues in nuclear physics and novel precision tests of fundamental symmetries.




Raghav Kunnawalkam Elayavalli

Disentangling various regimes of jet evolution

Jets are multi-scale processes produced via hard scattering collisions of relativistic hadrons. In their production, jets start as highly virtual quarks/gluons and evolve via a perturbative-QCD parton shower and finally result in a collimated collection of hadrons which we reconstruct in our detectors. Therefore, in each jet, we can potentially see a unique transition, i.e a shower topology from the high energy pQCD regime followed by fragmentation and hadronization which belongs to the non-perturbative or npQCD regime. Extracting this topological uniqueness across different jet populations (both at high and low energies) is crucial to gain an understanding of the space-time evolution of jets In this talk, I will highlight start of the art jet structure measurements from the STAR collaboration that focusses on using multi-differential observables which enable us to quantify the varying evolution regimes within jets. We will end by discussing exciting future prospects of using these observables in heavy ion collisions to study both hot and cold QCD physics.




Darcy Newmark 

The Coherent CAPTAIN-Mills Experiment

The Coherent CAPTAIN-Mills (CCM) experiment is an operating 10-ton liquid argon light collection detector located at Los Alamos National Lab studying neutrino and beyond Standard Model physics. The Los Alamos Neutron Science Center is equipped with an 800 MeV proton beam that impinges on a tungsten target, producing a large flux of neutrons, pions, electrons, and photons. The detector is located 23m downstream from the beam stop and 90 degrees off-axis, making it optimally sensitive to pion decays at rest. CCM will measure 2.25 x 1022 POT in the ongoing 3 year run cycle, producing a neutrino flux of 5.28 x 105 neutrinos/cm2/s at the detector. The prototype detector was constructed and took engineering run data in 2019, which produced physics results searching for ALPs and MeV scale QCD axion couplings to EM charge carries and light dark matter interactions. The detector instrumentation was upgraded in 2021 and the current physics goals are improving searches for axions, light dark matter, testing BSM solutions to the MiniBooNE anomaly, search for heavy neutral leptons, and various neutrino SM cross section measurements. In addition to instrumentation upgrades, the CCM collaboration is currently improving the signal reconstruction strategy to improve background rejection capabilities. This talk will focus on the analysis to identify Cherenkov light on an event-by-event basis, allowing particle identification – enabling improved sensitives to dark sector and BSM physics searches.



Juliana Stachurska 

The Project 8 Neutrino Mass Experiment - Latest Results and Future Directions

Project 8 is a next-generation experiment aiming to directly measure the neutrino mass using the tritium endpoint method. In order to cover the entire allowed region of effective electron neutrino mass in the case of an inverted neutrino mass hierarchy, Project 8 targets a sensitivity of 40 meV. The development of new technology and methods are required to reach this unprecedented sensitivity. Among these are the development of Cyclotron Radiation Emission Spectroscopy (CRES), a nondestructive method of measuring the differential energy spectrum of decay electrons established by Project 8, and the development of an atomic tritium source to overcome the statistic and systematic limitations associated with molecular tritium.

I will highlight the already achieved milestones, focusing on our recent first neutrino mass upper limit extraction with CRES. I will then present ongoing R&D work on the atomic source and scaling of CRES to larger volumes, and describe our next technology demonstrator.



Daniel Mayer 

Searching for Neutrinoless Double-Beta Decay and Beyond with CUORE

The worldwide quest to observe neutrinoless double-beta decay continues the long and successful history of using weak nuclear decays to explore the underlying properties of neutrinos, and search for new physics. CUORE, the Cryogenic Underground Observatory for Rare Events, is the first tonne-scale operating cryogenic neutrinoless double-beta decay experiment, instrumenting 742 kg of tellurium dioxide crystals at millikelvin temperatures. CUORE uses the cryogenic bolometer technique whereby temperature increases from particle energy deposition may be directly resolved with high resolution. With more than 2000 kilogram-years of detector exposure collected to-date, CUORE demonstrates the long-term stable operation of the technology at scale. In this talk, I will present recent searches for new physics with CUORE, including CUORE's latest search for neutrinoless double-beta decay in tellurium-130. Additionally, the analysis techniques and results from a search for an underground flux of fractionally-charged particles will be presented for the first time. Finally, I will discuss the future prospects of CUORE and its forthcoming successor, CUPID.



Maria Salatino






Miguel Arrati