Vote for the best experimental and theoretical posters at NuPhys 2023!
The voting form will open on Tuesday evening at the start of the poster session and close automatically during the conference dinner. For any questions or problems, please contact Jost Migenda (jost.migenda@kcl.ac.uk).
Experimental Posters
Title: The SNO+ journey towards 0vββ
Authors: Ana Sofia Carpinteiro Inacio, William Parker, Benjamin Tam
Abstract: SNO+ is a large multipurpose experiment with the ultimate goal of searching for the neutrinoless double beta decay of 130Te. After a commissioning phase with water as the target medium, during which acquired data allowed for measurements of solar neutrinos and the detection of reactor antineutrinos, SNO+ is now filled with 780 tonnes of liquid scintillator. The higher light yield of the scintillator enhances the physics capabilities of the experiment, and the physics program including reactor, geo and solar neutrinos is underway. The water and unloaded scintillator phases provide crucial commissioning milestones in preparation for the tellurium loading, such as calibrating the detector and making extensive background constraint measurements as components of the final scintillator cocktail are gradually added. In a first phase, 3900 kg of natural tellurium (0.5%) will be added to the scintillator for a predicted sensitivity of about 2e26 years (90% CL) with 3 years of livetime. Higher tellurium loading will follow for predicted sensitivities above 1e27 years (3% loading).
Number: EX-1
Title: Measuring SNO+ Scintillator Optics with SMELLIE
Authors: Ana Sofia Carpinteiro Inacio, Daniel Cookman, Po-Wei Huang
Abstract: SMELLIE is an in-situ optical calibration system in SNO+ developed to continuously measure and monitor the optical properties of the detector media, such as absorption, re-emission and scattering, without the need to deploy sources in the target medium and affect its radiopurity. The SMELLIE system is constituted by 4 short pulse diode lasers, with wavelengths 395, 407, 446 and 495 nm, and a broadband ‘supercontinuum’ laser, with a spectrum ranging from 400 to 700 nm. Laser light is injected into the detector via optical fibres located at several positions around the detector. The system has been taking data since the SNO+ water phase, and is now being used during the unloaded scintillator phase, to understand the detector response variation when new components are added to the detector. This poster aims to report the analysis and preliminary measurements from the scintillator phase, and point out the ongoing commissioning tasks in preparation of Tellurium phase.
Number: EX-2
Title: Calibration of the Scintillation Timing in SNO+ using In-Situ Backgrounds
Author: Rafael Hunt-Stokes
Abstract: The SNO+ Collaboration has recently concluded loading its liquid scintillator with PPO, the primary fluor, and the loading of the wavelength shifter, bisMSB, is ongoing. For each stage of the experiment, reliable position and energy reconstruction is essential, and in the face of a changing scintillator cocktail, methods have been developed to rapidly calibrate the SNO+ optical model. To this end, a novel technique for calibrating the time response of the SNO+ liquid scintillator using in-situ backgrounds was developed. By using in-situ coincident backgrounds, it is possible to calibrate both the beta and alpha time responses, as well as facilitate frequent monitoring of the background levels without compromising the radiopurity of the detector. A Bayesian Optimisation algorithm is employed to tune the optical timing parameters to match the response seen with tagged 214Bi (beta) and 214Po (alpha) events within the detector. Accurate calibration of the liquid scintillator emission times allows the exploration of time-based particle discrimination, such as between electron and gamma interactions.
Number: EX-3
Title: Cosmogenic Neutron Multiplicity in Water at SNO+
Author: Katharine Dixon
Abstract: For many underground experiments, neutrons produced by cosmic muons, as they traverse the detector, are a source of background. The number of neutrons they produce depends on the energy of the muon and the medium the muon is passing through. SNO+ is an underground detector which has the opportunity to measure the cosmogenic neutron yield in both water and scintillator, with the same muon flux. This will contribute to our understanding of these backgrounds which is important for any low background experiment. The work presented here shows the progress made on measuring the cosmogenic neutron yield during the water phase of SNO+, a task made complicated by the low threshold for observing the 2.2MeV neutron capture signal in water.
Number: EX-4
Title: Muon track reconstruction in the scintillator phase of SNO+
Author: Jasmine Simms
Abstract: The large depth of the SNO+ experiment (2070 m, 6010 m.w.e.) means that only a few muons per day pass through the detector. However, their high energy causes muon induced backgrounds which can affect multiple physics analyses. Reconstructing the muon track would allow for improved rejection for these induced backgrounds. Currently there is no muon tracker for the scintillator phase of SNO+. This poster presents a novel method of muon track reconstruction by using the high photon sampling from muons and the assumption that each PMT first registers a hit from a photon that takes the fastest possible path from the muon entry point to the PMT.
Number: EX-5
Title: Searching for neutrinoless double beta decay with the LEGEND experiment
Author: Giovanna Saleh
Abstract: Neutrinoless double beta ($0\nu\beta\beta$) decay is a hypothetical lepton-number-violating rare process which could take place if neutrinos were Majorana fermions: if observed, this decay would shed light on neutrinos' nature, would be an experimental evidence for lepton number violation and would provide insights on the origin of matter-antimatter asymmetry in the Universe.
The LEGEND experiment (Large Enriched Germanium Experiment for Neutrinoless double beta Decay) searches for the $0\nu\beta\beta$ decay of 76Ge employing active 76Ge-enriched detectors. In the first phase of the experiment, LEGEND-200, up to 200 kg of Germanium are deployed, leading to an expected half-life sensitivity beyond $10^{27}$ years within five years of data taking. LEGEND-200, currently operating at Gran Sasso National Laboratories (LNGS), started physics data taking in March 2023, after completing its commissioning in October 2022. The goal for the second and last phase of the experiment, LEGEND-1000, is to deploy 1000 kg of Germanium, for a final sensitivity beyond $10^{28}$ years to be achieved within ten years of data taking.
In this poster an overview of the LEGEND experiment is presented, with a focus on the current status of the experiment.
Number: EX-6
Title: Pulse shape discrimination for reduction of alpha background in HPGe detectors
Author: Krzysztof Szczepaniec
Abstract: In the search for rare nuclear processes using high-purity germanium (HPGe) detectors, alpha particles can pose a serious problem. Surface contamination of detector components by long-lived ${}^{222} \text{Rn}$ daughters, such as ${}^{210} \text{Po}$ or ${}^{210} \text{Pb}$, can generate background signals that are difficult to remove, potentially serving as a constant background source throughout the experiment's lifetime.
In experiments, every material is thoroughly cleaned and decontaminated to minimize the alpha background as much as possible. However, some contamination will inevitably persist. Given the extensive time and volumetric scale of experiments like LEGEND, which aims to detect neutrinoless double beta decay, a significant number of alpha-induced events will be registered. These events must be removed during the data analysis stage through dedicated quality cuts. Advanced methods of pulse shape discrimination can either accept or reject events on an event-by-event basis. Machine learning techniques, like dedicated neural networks, can be efficient in this task; however, a large sample of alpha events is required for efficiency verification.
Alpha-induced events in real experiments pose a challenge, yet there are not enough of them to be effectively used in the preparation of dedicated cuts. In this work, a dedicated pulse shape discrimination method has been developed. A large sample of clean alpha-induced events was obtained using a ${}^{210} \text{Po}$ contaminated foil placed on a p+ contact of the HPGe detector installed in a vacuum cryostat. This way, a total count of $10^{5}$ clean alpha pulses was collected and could be used for analysis.
The ROOT/TMVA projective-likelihood (PL) estimator, a multi-layer-perceptron (MLP) artificial neural network, and A/E methods were all investigated and tested against a set of alpha events. The investigated classification methods were exclusively trained on gamma events from a ${}^{228} \text{Th}$ calibration source and applied to the collected alpha events. The aim was to test if a PSD classifier trained and calibrated solely on gamma events can efficiently remove alpha events without any additional adaptation. This approach seeks to emulate large-scale experiments like LEGEND, where calibration runs with gamma emitters (i.e., ${}^{228} \text{Th}$) are regularly conducted, providing a perfect set of samples for training the machine learning models.
Number: EX-7
Title: The HOLMES low activity implantation
Author: Giovanni Gallucci
Abstract: The determination of the absolute mass of neutrinos is one of the open questions with many implications in particle physics and cosmology. The HOLMES experiment aims to directly measure the neutrino mass with a calorimetric approach by studying the electron capture decay of 163Ho. The very low Q value (2.8 keV), half-life (4570 y) and proximity of the end point to the M1 resonance make the 163Ho decay a great choice. The 163Ho will be incorporated into several microcalorimeter temperature (TES) detector arrays so that the energy released in the decay process is entirely contained within the detectors, except for the fraction carried away by the neutrino. A dedicated implanter with a sputter ion source, an accelerating section (up to 50 keV) and a magnetic dipole (for ion selection and beam focusing) was designed and developed to embed the source and repel the radioactive isotope 166Ho which could produce false signals in the region of interest. The machine is designed to achieve separation greater than 5σ @163/166 a.m.u. In this work, the commissioning of the machine and the production of the first set of low activity (O(1Bq/detector)) implanted TES will be described. Furthermore, this low activity phase of the experiment will lead to the most stringent limit (O(10) eV) on the neutrino mass with a calorimetric technique in just a few months of data collection.
Number: EX-8
Title: Design and Integration of JUNO-OSIRIS
Authors: Narongkiat Rodphai, Zhimin Wang
Abstract: The Jiangmen Underground Neutrino Observatory (JUNO) is a neutrino detection experiment characterized by a massive acrylic sphere, measuring 35.4 meters in diameter, containing 20,000 tons of liquid scintillator. This sphere is encompassed by as many as 17,600 photomultiplier tubes (PMTs) with a 20-inch diameter, achieving an overall coverage of 77.9%. With these impressive capabilities, the JUNO experiment aims to achieve an exceptional effective energy resolution of 3% at 1 MeV.
The Online Scintillator Internal Radioactivity Investigation System (OSIRIS) serves as a precursor detector, tasked with monitoring and examining the purity of the liquid scintillator prior to its transfer to the central JUNO detector. The OSIRIS pre-detector is constructed with a cylindrical acrylic vessel designed to hold 18 tons of liquid scintillator. It is situated within a 9-meter height cylindrical tank filled with 550 tons of pure water. This detector was specifically engineered to search for the fast coincidence decays of ^{214}Bi - ^{214}Po and ^{212}Bi - ^{212}Po in the decay chains of 238U and 232Th, respectively. It boasts an outstanding sensitivity of 10^-16 g/g. Additionally, 64 20-inch microchannel plate PMTs (MCP PMTs) were positioned around the liquid scintillator vessel to observe incoming interactions, along with an additional 12 20-inch MCP PMTs for the water Cherenkov muon veto system.
The OSIRIS pre-detector has been fully constructed and integrated, providing a plenty of preliminary results from the dry detector phase. The next step in the process involves commencing the filling of the liquid scintillator before the end of the year, aiming to involve an in-depth examination of the impurities within the liquid scintillator.
Number: EX-9
Title: Prototyping Opaque Scintillator Detector Technology
Author: Jess Lock
Abstract: The LiquidO consortium is bringing a new approach to scintillator detectors. Instead of the traditional transparent scintillator design, we use opacity (short scattering lengths and long absorption lengths) to force light to stay near the point of production. This concept has been proved both in simulations and our prototypes. The technology is intended to be implemented for neutrino physics with the SuperChooz experiment
Number: EX-10
Title: A Magnetised High-Pressure Gaseous Argon TPC for the DUNE Near Detector
Author: Francisco Martinez Lopez
Abstract: The Deep Underground Neutrino Experiment (DUNE) is a next-generation neutrino experiment that will consist of a near detector (ND) complex placed at Fermilab, several hundred meters downstream of the neutrino production point, and a larger far detector (FD) to be built in the Sanford Underground Research Facility (SURF), approximately 1300 km away. DUNE will record neutrino interactions from an accelerator-produced beam (the LBNF multi-megawatt wide-band neutrino beam planned for Fermilab) arriving at predictable times, but will also aim to detect rare events such as supernova neutrinos, potential nucleon decays and other beyond the Standard Model phenomena. The main role of the DUNE ND is constraining the systematic uncertainties in the neutrino oscillation measurements by characterising the energy spectrum and composition of the neutrino beam, as well as performing precision measurements of neutrino cross sections. The plan for DUNE is to be built using a staged approach with two main phases. While the Phase I ND complex is sufficient for early physics goals, a Phase II upgrade is planned in order to reach the designed sensitivity for the neutrino oscillation physics. One of the proposed options for Phase II is ND-GAr, a magnetised high-pressure gaseous argon TPC surrounded by an electromagnetic calorimeter (ECAL) and a muon system. The gaseous argon provides low detection thresholds, which would allow detailed measurements of nuclear effects at the interaction vertex using the same material as the FD. Additionally, the magnetic field and the ECAL would enable efficient particle identification and momentum and charge reconstruction. This poster presents an overview of the capabilities of ND-GAr and the ongoing efforts on the simulation and reconstruction software for the detector.
Number: EX-11
Title: The ASTAROTH project: an innovative light detector based on Silicon PhotoMultipliers for rare event physics and its applications in dark matter direct detection experiments
Author: Valerio Toso
Abstract: ASTAROTH (All Sensitive crysTal Array with lOw Threshold) aims to develop an innovative type of light detector based on the use of Silicon PhotoMultipliers (SiPM) and to study its application in rare event physics experiments (neutrino telescopes [1], dark matter direct search [2], ecc.).
The project aims to overcome the current limitations in the readout of NaI(Tl) scintillation by replacing traditional PMTs with Silicon PhotoMultipliers (SiPMs).
SiPMs are arrays of microcells made up of a single photon avalanche photodiode (SPAD).
They allow the reduction of the detection energy threshold down to the sub-keV region, a region of fundamental importance for dark matter direct detection experiments.
SiPMs have an excellent photon detection efficiency (PDE) of around 55% at 420 nm wavelength, making them an ideal sensor for NaI(Tl) scintillation light. SiPMs are compact detectors and this is a key-point in rare event physics experiments because of their low intrinsic radioactivity per unit mass.
SiPMs exhibit a decreased dark count rate with decreasing temperature, reaching a plateau below (70 − 80) K due to quantum tunneling of carriers. Below 150 K, SiPMs have a dark count rate two orders of magnitude lower than typical PMTs.
A demonstrator detector is being produced, featuring 1-2 encapsulated cubic crystals 5 × 5 × 5 𝑐𝑚3 to be operated at tunable temperatures.
Independent characterization of NaI(Tl) Crystals and SIPM technology is ongoing in different labs (INFN LASA-Milano, Milano Politecnico, INFN LNGS).
The cooling medium proposed for this experiment is liquid Argon, as it is an excellent scintillator that can be instrumented to act as a veto against several backgrounds.
I will present the status of the ASTAROTH project, introducing the innovative design of the detector chamber that will be used for the demonstration of the technology.
Then, I will show the preliminary results on the encapsulation of the NaI(Tl) crystals and on the characterization of the frontend electronics at cryogenic temperatures.
This technological developments will be useful not only for dark matter experiments (ASTAROTH), but for the whole astroparticle physics community.
Number: EX-12
Title: Atmospheric Background Reduction using CNNs in DSNB Searches at Super-Kamiokande Gd
Author: Soniya Samani
Abstract: The detection of the Diffuse Supernova Neutrino Background (DSNB) flux will provide invaluable insights into constraining cosmological models, core-collapse dynamics and neutrino properties. The Super-Kamiokande-Gd (SK-Gd) experiment currently exhibits the best sensitivity for discovery due to enhanced neutron tagging capability with $0.011\%$ $\text{Gd}_2(\text{SO}_4)_3 \cdot 8\text{H}_2\text{O}$, as per this analysis. While the Inverse Beta Decay (IBD) interaction is identifiable in SK-Gd, the low-energy signal is dominated by atmospheric neutrino backgrounds. This study explores a novel approach to background reduction by leveraging topological features of SK events with the discriminative power of Convolutional Neural Networks (CNNs). Well-established techniques for data pre-processing, event selection and feature extraction are used to train CNNs on IBD and atmospheric Neutral Current (NC) Monte-Carlo (MC) events. Preliminary performance of two CNN models highlights the potential of using machine-learning techniques to improve the DSNB signal efficiency.
Number: EX-13
Title: Modelling Cosmic Ray Muon Spallation for a Hyper-Kamiokande DSNB Analysis
Author: Jack Fannon
Abstract: Hyper-Kamiokande (HK) will be a 260 000 tonne water Cherenkov detector located in the Gifu Prefecture of Japan. The primary research topic of HK is the neutrino, a neutral particle that rarely interacts with matter. As such, neutrinos from specific sources are challenging to detect in the presence of overwhelming backgrounds. One background of specific interest is events caused by cosmic ray muon spallation, particularly the decay of radioactive isotopes caused by the spallation of oxygen nuclei in the HK water. High-energy muons are produced in the upper atmosphere when pions, created by interactions between the atmosphere and cosmic rays, decay to a muon and its corresponding neutrino. Even though the HK overburden of 1750 m.w.e will reduce the flux of cosmic ray muons by a factor of ~60 000, it is still expected that 45 muons per second will cross the detector where there is approximately 1 spallation interaction per muon. Although many daughter isotopes of the spallation process are stable or decay in ways that do not produce Cherenkov radiation, 16 nuclei can be created that cause a significant background in analyses focused in the 0-20 MeV range. One such analysis is the search for diffuse supernova background neutrinos (DSNB). These are the cumulative neutrinos created by all past core-collapse supernovae in the universe, the detection of which would provide information into the mechanisms behind star formation and the rate at which they are created. Presented here is the development of an MC simulation, combining output from multiple particle physics simulations, to model the spallation background at HK and its predecessor, Super-Kamiokande (SK). Current results for SK show a good agreement between simulation and data, and preliminary results from training a machine learning classification display a good reduction power of a gradient-boosted algorithm.
Number: EX-14
Title: Multiperspective neutrino studies
Author: Sara Rodríguez Cabo
Abstract: The central theme of my doctoral thesis, carried out at the University of Oviedo, is the study of the characteristics of neutrinos from different points of view.
On the one hand, the possible usefulness of cosmological effects, such as weak lensing, in estimating limits on the value of the sum of the neutrino masses is being studied. It has been found that the cross-correlation, a manifestation of the magnification bias, is sensitive to the value of the sum of the neutrino masses, so that a fit of this function to the experimental data can provide restrictive limits on this parameter.
Simultaneously, work is starting on the development of artificial intelligence algorithms to improve the identification of tau neutrino events in detectors by developing neural networks and a reasonable choice of input variables to distinguish tau-like events from the background. Furthermore, the aim is to subsequently carry out an in-depth analysis of the results to allow the calculation of parameters such as the effective cross-section.
In addition, a very complete study has been carried out on the compensation of the geomagnetic field by means of coil systems in Cherenkov type detectors, in which the effect of different associated parameters, such as the size or the distance between spires, is studied, and a basic compensation system is proposed which offers optimum results. These results are currently being applied in the design of the compensation system of the Hyper-Kamiokande neutrino detector.
Number: EX-15
Title: A new era of collider neutrino physics at the LHC: the SND@LHC experiment
Author: Riddhi Biswas
Abstract: Scattering Neutrino Detector at the Large Hadron Collider (SND@LHC) is a compact and stand-alone experiment built to perform measurements with neutrinos produced at the LHC in a hitherto unexplored pseudo-rapidity region of 7.2 < 𝜂 < 8.6, complementary to all the other experiments at the LHC. The experiment is located 480 m downstream of IP1 in the unused TI18 tunnel. The detector is composed of a hybrid system based on an 800 kg target mass of tungsten plates, interleaved with emulsion and electronic trackers, followed downstream by a calorimeter and a muon system. The configuration allows efficient distinguishing between all three neutrino flavours, opening a unique opportunity to probe the physics of heavy flavour production at the LHC in the region that is not accessible to ATLAS, CMS and LHCb. This region is of particular interest also for future circular colliders and for predictions of very high-energy atmospheric neutrinos.
In this poster, we will discuss the detector concept and the physics goals we plan to achieve. We will also report the official results from the collaboration such as the ongoing efforts for neutrino searches, muon flux background (EP pre-print: http://cds.cern.ch/record/2872668) and emulsion vertex analysis. Most importantly, we will report the recent findings of the direct observation of the muon neutrino interactions using the 2022 13.6 TeV proton-proton collisions (integrated luminosity of 36.8 fb−1) dataset from the active electronic components of the SND@LHC detector: PRL publication https://doi.org/10.1103/PhysRevLett.131.031802. Lastly, we will discuss further physics prospects of SND@LHC, as well as future plans for an upgraded version of the experiment for the high-luminosity LHC running (Advanced SND@LHC), planned for the end of this decade.
Number: EX-16
Title: Flavour measurements from track events at the IceCube Neutrino Observatory
Author: Rogan Clark
Abstract: The IceCube Neutrino observatory is a cubic-kilometre scale ice Cherenkov detector, located at the South Pole. We use a sample of events which start in instrumented ice, of energy > 1 TeV and with full-sky coverage, to put bounds on the astrophysical neutrino flavour composition, using a novel method to improve muon/tau separation.
Number: EX-17
Title: Cryogenic power over fiber for fundamental and applied physics at Milano-Bicocca: the Cryo-PoF project
Author: Marta Torti
Abstract: The power over fiber (PoF) technology delivers electrical power by sending laser light through an optical fiber to a photovoltaic power converter, in order to power sensors or electrical devices.
Removal of noise induced by power lines, robustness in a hostile environment, spark free operation, when electric fields are present, and no interference with electromagnetic fields are some of the advantages this solution can offer.
The technology is at the basis of the Cryo-PoF project: an R&D funded by the Italian Institute for Nuclear Research (INFN) in Milano-Bicocca (Italy).
Cryo-POF is inspired by the needs of the DUNE Vertical Drift detector, where the VUV light of liquid argon must be collected at the cathode, i.e. on a surface whose voltage exceeds 300 kV. To power both the Photon Detection devices and its electronic amplifier, we aim to develop a cryogenic system, solely based on optoelectronic devices and a single laser input line.
In this poster we will presents the results obtained during test campaign performed in Milano- Bicocca. Also the performances of the system at temperature below the liquid nitrogen one will be presented, for Cryo-PoF potential application in the field of applied physics.
Number: EX-18
Title: The front-end electronics of the DUNE Photon Detection System
Author: Esteban Javier Cristaldo Morales
Abstract: The DUNE (Deep Underground Neutrino Experiment) will consist of two detectors exposed to a high intensity neutrino beam and separated by a distance of 1300 km: the far detector, with a projected fiducial mass of 40kt of liquid argon and located 1.5 km underground at the Sanford Underground Research Facility (SURF) in South Dakota, U.S.A; and the near detector, located near the beam source at FERMILAB, in Illinois, U.S.A. DUNE will significantly advance the technology of Liquid Argon Time Projection Chambers and leverage an innovative system for detecting argon scintillation light. This Photon Detection System (PDS) is based on the X-ARAPUCA concept, where 128 nm photons produced by argon scintillation are wavelength-shifted by WLS organic components and trapped by a dichroic filter. Trapped photons are recorded by a large number (up to 80 per channel) of 6x6 mm2 cryogenic SiPMs, either read out in parallel (first DUNE module) or in 'hybrid ganging mode' (second DUNE module). The front-end electronics consist of a cryogenic trans-impedance amplifier and a custom board operating at room temperatures (DAPHNE). I will present the results of the front-end electronics validation carried out at the University of Milano Bicocca and CERN in 2023 for both DUNE modules, along with the end-to-end simulation of this system. I will particularly discuss the results obtained in terms of noise suppression, sensitivity to single photoelectron, dynamic range, and the exceptional sensitivity achieved for such a large number of SiPMs, reaching up to a silicon surface of 28.8 cm2.
Number: EX-19
Title: Alpha spectrometry measurements for low-background experiments
Author: Milena Czubak
Abstract: Detection of rare nuclear processes (i.e. dark matter, neutrinoless double beta decay searches) requires background suppression practically to zero in order to maximize detectors’ sensitivities. This imposes strict conditions for construction materials for detectors in this type of experiments.
One of the most important background sources in direct dark matter searches are neutrons, especially those produced in (alpha, n) reactions. A significant fraction of these neutrons may be generated by residual activity of Po-210, which is a daughter of the long-lived Pb-210. It has been found that the Pb-Po sub-chain may be in dis-equilibrium with U-238 and Ra-226 thus, a dedicated detection method is needed to establish the Pb-210 content in various detector’s components.
Alpha spectrometry allows to determine not only the alpha activity on the surface of a sample but also in a thin sub-surface layer. Its thickness corresponds to the range of 5.3 MeV alpha particles in a given material. This opens up the possibility for determination of the bulk Po-210 content by alpha spectrometry. A series of Po-210 measurement in time yields also the Pb-210 concentration (which is the most relevant). In order to determine the surface and bulk Po activities for a given sample, the registered energy spectrum has to be de-convoluted with the help of appropriate Monte Carlo simulations. Applying for measurements a low background large surface alpha spectrometer detection limits of 0.5 mBq/m$^2$ and 50 mBq/kg were obtained for the surface and bulk activity concentrations, respectively.
In the poster details of the analysis and some selected results will be presented.
Number: EX-20
Title: BUTTON (Boulby Underground Technology Testbed Observing Neutrinos) experiment
Author: James Gooding
Abstract: The BUTTON (Boulby Underground Technology Testbed Observing Neutrinos) experiment under construction in Boulby mine is a water-based Cherenkov detector for detecting reactor antineutrinos. Detection of reactor antineutrinos can be used for remote monitoring of nuclear sites and nonproliferation. BUTTON will be used as a testbed of new cutting-edge technology development such as gadolinium doped fill media, advanced photosensors such as LAPPDs (Large-Area Picosecond Photodetectors) and water-based liquid scintillators. The 30-tonne capacity tank is currently being constructed with initial media fills and data-taking planned to commence in 2024.
Number: EX-21
Title: Updated Treatment of Near Detector Systematics Uncertainties for the T2K 2024 Oscillation Analysis
Author: Ewan Miller
Abstract: In order for T2K to continue to produce world leading measurements of neutrino oscillations parameters as we move into the precision era of neutrino physics, we require the use of state of the art techniques in all parts of our analyses. The purpose of the near detector analysis within the wider T2K oscillation analysis is to constrain uncertainties relating to neutrino-nucleus interaction cross sections, as well as on the energy dependent fluxes for each neutrino flavour for the neutrino beamline. In order to properly constrain these uncertainties, we also need to account for detector specific systematic errors, which parameterise uncertainties on reconstruction algorithm efficiencies, as well as uncertainties on physical aspects of the detector such as the masses of certain materials, number of pileup events etc.
This poster details the development of a new and improved treatment of these detector systematic uncertainties for the 2024 near detector analysis. The previously used treatment approximates the overall effect of these parameters on each analysis bin as a Gaussian smear. This treatment obscures the effect of individual underlying uncertainties, and leads to a highly inflated number of parameters in our fits, as it requires one fit parameter for every bin. Furthermore, it is known that the Gaussian approximation breaks down for many bins, leading to an over estimation of these errors. The new treatment is based on an event by event reweighting, which allows us for the first time to directly assess the impact of these uncertainties on our fits and also greatly reduces the number of parameters which need to be fit in the analysis.
Number: EX-22
Title: Presenting Neutrino Oscillation Results in the Precision Era
Author: Marvin Pfaff
Abstract: According to our current understanding, neutrinos come in three flavours with three related mass eigenstates, resulting in a unitary 3x3 matrix relating the two sets of eigenstates. This is the so-called leptonic mixing matrix (LMM) and is most-commonly shown in the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) parameterisation using three mixing angles and one complex phase. However, the anomalies in short-baseline neutrino experiments may suggest that there could be more than just three neutrinos. The next-generation of long- and medium-baseline oscillation experiments will move from being statistics limited to systematics limited and hence enter the precision era. This means that experiments will be able to measure the parameters of the LMM so precisely that they become sensitive to non-unitary effects. In such a non-unitary case, the PMNS parameterisation with three mixing angles and one complex phase will not hold anymore and unitarity-invariant presentations have to be used to quantify neutrino oscillations. The theory community has already started to explore possibilities for such unitarity-invariant presentations but the experimental community has yet to follow. By implementing such invariant presentations already now, the whole community will be able to get accustomed to these new presentations and strengthen their intuition by the time these will become indispensable tools for the community.
Number: EX-23
Title: Appearance of Tau Neutrinos in the Flux of Atmospheric Neutrinos at Super-Kamiokande
Author: Maitrayee Mandal
Abstract: This poster presents Super-Kamiokande's latest results on the appearance of tau neutrinos from neutrino oscillations in the flux of atmospheric neutrinos. The dataset is for a live-time of 6511.3 days recorded from 1996 to 2020, and accounts for all of the pure-water runs at Super-Kamiokande. The exposure of the detector is 484.2 kT-years. 428$\pm$92 oscillated tau neutrino events have been observed. The measured tau neutrino normalisation is 1.36$\pm$0.29. We exclude the hypothesis of no tau neutrino appearance with a significance of 4.8$\sigma$.
Number: EX-24
Title: Non-Unitary Atmospheric Neutrino Mixing At Super-Kamiokande
Author: Rory Ramsden
Abstract: Current constraints on the tau row matrix elements of the leptonic mixing matrix are determined from the electron and muon row, assuming unitarity conditions. This is due to the difficult nature of detecting tau neutrinos. However, by relaxing the unitary matrix constraint by way of sterile neutrino mixing with the three active neutrino flavours, one can attempt to measure the difference in atmospheric neutrino event rate between the unitary matrix scenario and a unitary-violating scenario at the Super-Kamiokande water Cherenkov detector in Japan and determine new matrix element limits. This poster presents the beginning of such an analysis and how the oscillation framework changes with the inclusion of sterile neutrinos.
Number: EX-25
Title: An overview of the current status of the Hyper-Kamiokande Experiment
Author: George Burton
Abstract: Hyper-Kamiokande is the third generation of ring imaging water Cherenkov detector currently being developed in Japan. It will be the successor to the double Nobel prize winning Super-Kamiokande experiment that is located in the Gifu prefecture. Functioning as the far detector to the JPARC neutrino beam, with a long baseline of 295km, Hyper-K will supersede the sensitivity of the Super-K detector due to its’ significantly increased size. Therefore, it will be able to make high precision measurements of important oscillation parameters as well as have the potential to observe BSM phenomena such as proton decay. We will present the current status of the detector, the construction stages and aim to contextualise the role of Hyper-K within the framework of the beam-line and near detectors (ND280 and INGRID).
Number: EX-26
Title: Probing Neutrino Oscillations with Reactor Antineutrinos in JUNO
Author: Vanessa Cerrone
Abstract: The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino experiment currently under construction in South China, in an underground laboratory with approximately 650 m of rock overburden (1800 m.w.e.). The detector consists of a 20 kton liquid scintillator (LS) target, contained inside a 35.4-meter-diameter spherical acrylic vessel. The central detector is equipped with 17,612 20-inch and 25,600 3-inch photomultipliers tubes, providing more than 75% total photocathode coverage.
JUNO's main goal is the determination of the Neutrino Mass Ordering (NMO) with reactor antineutrinos, emitted from two adjacent nuclear power plants on a $\sim$ 52.5 km baseline from the experimental site.
The design of the detector is mainly driven by its physics requirements. Indeed, to achieve a $\sim 3-4\sigma$ NMO significance in about 6 years of data-taking, unprecedented energy resolution for a LS-based experiment ($\leq 3\%$ at 1 MeV) and accurate control of the energy scale (i.e., overall non-linearity effects below 1%) are needed.
JUNO's strategic location at a baseline corresponding to the first solar oscillation maximum, where the kinematic phase $\Delta_{21} \simeq \frac{\pi}{2}$, grants it the unique capability to simultaneously probe the effects of oscillations on both solar and atmospheric scales; moreover, it stands out as the first experiment to address the unresolved NMO question through vacuum-dominant oscillations.
The oscillated energy spectrum in JUNO changes subtly depending on the neutrino mass ordering, which manifests as an energy-dependent phase shift, thus providing sensitivity to this parameter. Furthermore, the unparalleled size and energy resolution will enable the independent measurement of four oscillation parameters: $\Delta m_{21}^{2}$, $\Delta m_{31}^{2}$, $\sin^2\theta_{12}$, and $\sin^2\theta_{13}$, achieving a sub-percent precision for the first three parameters.
This contribution will focus on JUNO's oscillation physics with reactor antineutrinos, with a particular emphasis on its crucial role in inaugurating a new era of precision within the neutrino sector.
Number: EX-27
Title: Translating Near to Far Detector for DUNE Oscillation Analysis
Author: Alexander J Wilkinson
Abstract: The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino oscillation experiment that aims to measure CP-violation in the neutrino sector as part of a wider physics programme. DUNE consists of a near detector and far detector situated 1.5km underground and at a baseline of 1300km. The detectors are exposed to a wide band neutrino beam generated by a 1.2MW proton beam with a planned upgrade to 2.4MW. The Precision Reaction Independent Spectrum Measurement (PRISM) refers to the capacity of part of the DUNE near detector to move off-axis from the beam to sample different neutrino energy spectra. Due to the wide range of off-axis positions, the set fluxes can be treated as a linearly independent basis and combined to approximate any target flux. This is used to extract oscillation parameters with little dependence on an interaction model by producing a prediction of the oscillated spectrum at the far detector using near detector measurements. An important part of this extrapolation is to correct for the differences in resolution and efficiency of the detectors with minimal reliance on Monte Carlo. This work presents a deep learning approach to accomplish this by predicting the far detector response given a near detector neutrino event. The problem is posed as an image-to-image translation between two domains defined by the distinct types of detector technology. The capacity for the model to accurately predict far detector reconstructed variables is demonstrated and the network is integrated in the simulation chain to conduct an initial study of its performance over Monte Carlo based smearing.
Number: EX-28
Title: SoLAr: a novel technology for solar neutrino detection
Author: Guilherme Ruiz Ferreira
Abstract: The SoLAr concept introduces a novel liquid-argon neutrino detector technology to enhance sensitivity in the MeV energy range, broadening the scope to include solar and supernova neutrinos. This technology is based on a monolithic light-charge pixel-based readout, offering a low energy threshold, exceptional energy resolution (approximately 7%), and effective background rejection through pulse-shape discrimination. The primary objective is to observe solar neutrinos in a 10-kiloton-scale detector, ultimately leading to precise measurements of the $^8$B flux, improved solar neutrino mixing parameters, and the first observation of the hep neutrino flux. It is also a timely technology choice for the DUNE “Module of Opportunity”, which could serve as a next-generation multi-purpose observatory for neutrinos from the MeV to the GeV range. A staged prototyping program is in progress to validate the viability of this detector concept, with a prospect to build a medium-sized demonstrator in the Boulby Underground Laboratory. Here, we present preliminary results from the prototype run in July 2023, showcasing cosmic muon tracks detected for the first time with an integrated light and charge readout.
Number: EX-29
Title: Measuring Solar Neutrino Oscillations in the SNO+ Detector
Author: Daniel Cookman
Abstract: The SNO+ experiment is a large multi-purpose neutrino detector, currently filled with liquid scintillator. For the first time in a single experiment, SNO+ is able to measure the neutrino oscillation parameters θ₁₂ and Δm²₂₁ simultaneously through both reactor anti-neutrinos and Boron-8 solar neutrinos. This poster demonstrates the latter approach, with an analysis of an initial 80 days of scintillator phase data. A Bayesian statistical approach via Markov Chain Monte Carlo is used, allowing for the simultaneous fitting of the oscillation parameters, Boron-8 neutrino flux, background components with constraints, and floating systematics. The neutrino oscillation parameter θ₁₂ was measured to be 38.9◦+8.0◦−7.9◦, assuming the current global fit flux of Boron-8 solar neutrinos. This is consistent with the current global fit result for θ₁₂. A sensitivity study shows that this measurement is statistics-limited, and precision could be improved by a factor of two with two years of livetime, assuming the same backgrounds and selections.
Number: EX-30
Title: MINERνA Data Preservation: Enabling Muon Fuzz Analysis.
Author: Akeem Hart
Abstract: MINERνA is a scintillator-based neutrino detector at Fermilab, along the well-studied NuMI neutrino beam. Amongst neutrino detectors, MINERνA is uniquely adept in directly investigating how differences in the nuclear environment affect our observations of neutrino interactions. Muon fuzz refers to the tracks left behind by delta rays and bremsstrahlung produced by a muon transiting the detector. Correctly identifying the muon fuzz has uses ranging from neutrino energy reconstruction to model validation. Herein, efforts to extend MINERνA's existing ability to identify this muon fuzz with a particular emphasis on its utility for future analyses are presented.
Number: Ex-31
Theoretical Posters
Title: Towards the detection of ultra-low energetic neutrinos with plasma metamaterials
Author: Carlo Alfisi
Abstract: Highly energetic neutrinos have been successfully detected in experiments such as IceCube or Super-Kamiokande. Conversely, neutrinos in the ultra-low energy range (E < 1.0 eV) have been theoretically predicted but their observation remains so far elusive. Here, we propose a scheme based on graphene metamaterials for the detection of such ultra-low energetic neutrinos. Slow neutrino fluxes can trigger a plasmon instability in the metamaterial due to the weak force, which is reminiscent of the beam-plasma instability taking place in astrophysics. We make use of the semiclassical form of the equations governing the weak interaction to describe the coupling between the neutrinos and electrons in graphene. To render the scheme practical, we investigate the neutrino-plasma instability produced in a metamaterial composed of a periodic stacking of bilayer graphene sheets.
Number: TH-1
Title: Pseudo-Dirac neutrinos at JUNO
Author: JACK,DENNIS FRANKLIN
Abstract: We explore the scenario of Pseudo-Dirac neutrinos, where the mass degeneracy of Dirac neutrinos is lifted due to a soft breaking of the lepton number, resulting in 3 pairs of mass states which are maximally mixed.
Using prospects on the measurement of pp and $^7$Be solar neutrinos in JUNO, we will demonstrate the capability of the experiment to explore the parameter space of including one of these extra finely split mass states, as well as the bounds it will be able to set on the full pseudo-Dirac scenario. We will show that JUNO will be able to put a $3\sigma$ limit on the mass splitting being $\delta m^2 \lt 1.19 \times 10^{-13}$ eV$^2$ for a full Pseudo-Dirac scenario with identical mass splittings.
Number: TH-2
Title: Hunting for the cosmic neutrino background
Author: Jack Shergold
Abstract: The cosmic neutrino background is a firm prediction of Lambda-CDM cosmology, which at present remains undetected. A successful detection of the cosmic neutrino background could give deep insight into the evolution of the universe, aid in the determination of the absolute neutrino mass, and potentially distinguish between Dirac and Majorana neutrinos. With my poster, I will give a brief introduction to the cosmic neutrino background, as well as an overview of several relic neutrino detection proposals.
Number: TH-3
Title: Second leptogenesis: a source of large discrepancy between baryon and lepton asymmetries
Authors: YeolLin ChoeJo, Kazuki Enomoto, Yechan Kim, Hye-Sung Lee
Abstract: The recent 4-helium abundance observation suggests the large lepton asymmetry which is 8 orders larger than the baryon asymmetry at 2.5σ level. Traditional baryogenesis scenario cannot explain it because the sphaleron process make them to be the same size. In this work, we have proposed a novel scenario to explain this discrepancy by the twofold leptogenesis caused by the temperature-dependent mass of heavy Majorana neutrinos. If the first and second leptogensis occur before and after the sphaleron decoupling, respectively, generated lepton number in the first leptogenesis is converted to the baryon number via the sphaleron process; on the other hand, that in the second leptogenesis remains until the current universe. This extra lepton number production can make the large discrepancy. We have shown that the second leptogenesis can significantly amplify the lepton asymmetry and the value can be remarkably close to the observed data. The reference is arXiv:2311.16672 [hep-ph].
Number: TH-4
Title: Probing the Nature of Heavy Neutral Leptons in Direct Searches and Neutrinoless Double Beta Decay
Authors: Patrick Bolton, Frank F Deppisch, Mudit Rai, Zhong Zhang
Abstract: Heavy Neutral Leptons (HNLs) are a popular extension of the Standard Model to explain the lightness of neutrino masses and the matter-antimatter asymmetry through leptogenesis. Future direct searches, such as fixed target setups like DUNE, and neutrinoless double beta decay are both expected to probe the regime of active-sterile neutrino mixing in a standard Seesaw scenario of neutrino mass generation for HNL masses around $m_N \lesssim 1$~GeV. Motivated by this, we analyse the complementarity between future direct searches and neutrinoless double beta decay to probe the nature of HNLs, i.e., whether they are Majorana or quasi-Dirac states, and CP-violating phases in the sterile neutrino sector. Following an analytic discussion of the complementarity, we implement a generic fixed target experiment modelling DUNE. We perform a statistical study in how a combined search for HNLs in direct searches and neutrinoless double beta decay, using DUNE and LEGEND-1000 as representative examples, can probe the nature of sterile neutrinos.
Number: TH-5
Title: High-energy neutrinos, magnetic moment and the strong magnetic field: Impact on the Flavor Composition and Glashow Events
Author: Ting Cheng
Abstract: IceCube collaboration pioneered in detecting $\mathcal{O}{(\text{PeV})}$ neutrino events as well as in identifying astrophysical neutrino sources. In this work we consider the scenario where such high-energy neutrinos get produced in the vicinity of the astrophysical objects, e.g. magnetars, which source strong magnetic fields. We thoroughly investigate the impact of the strong magnetic field to the neutrino propagation for non-vanishing neutrino magnetic moments. Provided a significant number of to be detected high-energy neutrinos will traverse regions with $B\gtrsim 10^3$ G, we find that observable features at neutrino telescopes are expected for presently unconstrained values of the neutrino magnetic moment. In particular, for several high-energy neutrino production mechanisms, we demonstrate that the expected flavor composition and the number of predicted Glashow events can strongly alter.
Number: TH-6
Title: Electric Charge Breaking in Neutrino Physics
Author: Manuel Salewski
Abstract: My poster will be on **a new framework for electric charge breaking** and its repercussion for neutrino physics. I break the U(1)$_\text{EM}$ of the standard model by introducing new general scalar fields that obtain vacuum expectation values in non-neutral components.
I will briefly discuss the basic mechanism and how it leads to photon mass, charge corrections for fermions, and new interactions between standard model particles, all while acknowledging the most recent and stringent experimental bounds. I will then illustrate three applications:
- **Electron-neutrino-photon interactions** - This type of interaction can only appear when electric charge is broken. I show how the corresponding cross section depends non-trivially on the photon mass and does not, in fact, have a smooth limit as the mass goes to zero.
- **Electron and photon decay** - Connected to the point above, I derive the lifetime of the electron (decaying into photon and neutrino) and the photon (decaying into neutrinos / anti-neutrinos) in this framework.
- **Neutrino magnetic moment** - I examine the expected tree-level magnetic moment for the neutrino in this framework, which arises regardless of its Majorana/Dirac nature.
Number: TH-7
Title: Neutrinos as possible probes for quantum gravity
Author: MARCO DANILO CLAUDIO TORRI
Abstract: Astrophysics represents one of the most promising sectors for the search of quantum gravity (QG) evidences, since the envisioned phenomenological effects will be more pronounced, benefiting from the high energies and long free propagation path of cosmic messengers. Within the realm of astroparticles, neutrino can assume an important role in the search for QG residual signatures. The main objective of this study is to investigate the relationship between neutrinos and QG, exploring various proposals regarding the potential use of these particles as tools to investigate the nature of spacetime. The residual traces of a more fundamental QG theory may manifest through changes in the dispersion relations of free particles and their associated propagation velocities. Within the realm of neutrinos, these effects can lead to variations in the time of flight for astrophysical particles across a wide range of energies. This becomes evident in multi-messenger investigations of events such as gamma-ray bursts (GRB) and supernova explosions, where dissimilar time-of-flight measurements for neutrinos of different energies can be observed.
Additionally, neutrino sector can also be used to investigate the universality of the particle interplay with gravity. Indeed, QG signatures have the potential to perturb conventional neutrino oscillation patterns by introducing species-dependent deviations, for instance in the atmospheric neutrino sector.
These theoretical and phenomenological predictions are constructed within the framework of various research models, including the Standard Model Extension (SME), Doubly Special Relativity (DSR), and generalized Finsler geometry (HMSR model). Through this exploration, we aim to enhance our understanding of the interplay between neutrinos and QG, explaining how to use these particles for the search of residual QG signatures. Furthermore, we intend to address the challenges and propose potential future directions in this intriguing field of research.
Number: TH-8
Title: Reconstruction of Neutral Final-State Particles in Neutrino-Argon Interactions
Author: Margot MacMahon
Abstract: Faithful energy reconstruction is foundational for precision neutrino experiments. While DUNE will offer unprecedented event reconstruction, uncertainties remain, for instance, the unknown initial-state momentum of the struck nucleon. We demonstrate that graph neural networks are highly effective in overcoming these uncertainties by estimating inaccessible kinematic variables based on the observable part of the final state. Our networks outperform conventional reconstruction algorithms both in terms of precision and of accuracy (avoiding the few per cent bias which can be present from other methods).
Number: TH-9
Title: Investigating the use of the z expansion formalism when modelling axial form-factors in CCQE
Author: Abi Peake
Abstract: Understanding neutrino-nucleon Charged-current Quasi-Elastic scattering (CCQE) is of great importance to long-baseline neutrino oscillation experiments. The axial component of the nucleon weak-charge distribution ($F_{A}$) is a key component in modelling CCQE interactions. In previous analyses, has been modelled using a 1-parameter dipole form (which turns out to be insufficient when modelling CCQE interactions across a range of four momentum transfer). An alternative, improved method uses the multi-parameter z expansion formalism, however this parameterisation has drawbacks when applied to long-baseline oscillation analyses because it is not possible to factorise the free parameters from the cross-section. One way around this concern is to use an alternative set of parameters in the z expansion formalism. This poster describes an investigation into the practical application of an alternate parameterisation, and the implementation of this parameterisation in to NuSystematics.
Number: TH-10
Title: Neutrino energy scale measurements for final sate interaction models in DUNE using advanced computing
Author: Aleena Rafique
Abstract: The Deep Underground neutrino experiment (DUNE), consisting of near (DUNE-ND) and far (DUNE-FD) detectors, is a long-baseline experiment that is designed to measure neutrino oscillations, as well as searches beyond the standard model. The DUNE-FD will operate with a total volume of 70 kiloton liquid argon and will be situated at Sanford Underground Research Facility (SURF) in South Dakota. The DUNE near detector (DUNE-ND) will be placed close to the neutrino source and measure an un-oscillated neutrino beam for precise measurement of oscillation parameters. Final State Interactions (FSI) are the secondary interactions of the daughter particles of the neutrino with other nucleons within the same Ar nucleus. I will present the impact of using different final state interaction models on the neutrino energy scale measurements in DUNE using advanced computing at Argonne.
Number: TH-11
Title: 2p-2h Cross Section Systematics in DUNE
Author: Lars Ludwig Hans Bathe-Peters
Abstract: For the operation of precision neutrino experiments, the understanding of neutrino interactions with matter are preconditioned requirements of all detections and measurements of neutrinos. The largest uncertainties in estimating neutrino-nucleus interaction cross sections arise in the incomplete understanding of nuclear effects. In the study of neutrino oscillations and nuclear scattering processes, obtaining an interaction model with associated uncertainties is of sub- stantial interest for the neutrino physics community. This report presents studies of simulated CC 2p-2h interactions, in which a neutrino interacts with a bound pair of nucleons. This interaction mode is very poorly constrained by current data. A comparison of three leading CC 2p-2h models is presented, along with a number of uncertainty parameters that have been implemented to account for model-to-model discrepancies in the DUNE oscillation analysis.
Number: TH-12
Title: Differentiable nuclear deexcitation simulation for low energy neutrino physics: What, Why and How.
Authors: Pablo Samuel Barham Alzas, Radi Radev
Abstract: Neutrino-nucleus interactions play a significant role in present and future neutrino experiments. The accurate simulation of these interactions at low energies (<100 MeV) is crucial for the detection and study of supernova, solar and atmospheric neutrinos.
In particular, the reconstruction of the incoming neutrino properties depends on the ability to measure the products from the deexcitation of the final state nucleus after the initial neutrino-nucleus scattering reaction. A realistic nuclear deexcitation model that can correctly manage the theoretical uncertainties in the process is key to determine the response of a detector to low energy neutrinos and estimate the overall systematic uncertainties that affect it.
Automatic differentiation frameworks like PyTorch or JAX, widely used in the field of Machine Learning, provide us the tools to compute exact gradients of the simulation outputs with respect to the model parameters. Such differentiable simulators can be applied in simulator tuning to match observed data and forward modeling to efficiently infer the impact of parameter distributions to the physics output, or for parameter inference acting as a likelihood estimator. This paradigm can pave the way to a fully differentiable analysis of the whole simulation chain or direct integration with preexisting Machine Learning tools.
As a proof of concept, in this work we implement a fully differentiable nuclear deexcitation simulation based on a simplified version of the Hauser-Feshcbach statistical emission model. This is akin to the one used by MARLEY, the standard event generator for low energy neutrino physics in LArTPC experiments like DUNE. We demonstrate the feasibility of this approach and showcase some of its applications like parameter tuning via gradient descent or smooth reweighting of the model parameters. We also explore its limitations and potential for improvement and scaling.
Number: TH-13
