BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//LBNL Physics Division Research Progress Meetings - ECPv6.8.3//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-ORIGINAL-URL:https://rpm.physics.lbl.gov
X-WR-CALDESC:Events for LBNL Physics Division Research Progress Meetings
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:UTC
BEGIN:STANDARD
TZOFFSETFROM:+0000
TZOFFSETTO:+0000
TZNAME:UTC
DTSTART:20250101T000000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=UTC:20250701T160000
DTEND;TZID=UTC:20250701T170000
DTSTAMP:20260414T232941
CREATED:20250626T213202Z
LAST-MODIFIED:20250626T213202Z
UID:2866-1751385600-1751389200@rpm.physics.lbl.gov
SUMMARY:Speaker: Marco Bonici (Waterloo) - Title: Taming projection effects in galaxy clustering analysis
DESCRIPTION:Research Progress Meeting \nDate: July 1\, 2025 \nTime: 4:00- 5:00 pm \nLocation: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]  \nSpeaker: Marco Bonici (Waterloo) \nTitle: Taming projection effects in galaxy clustering analysis \nAbstract: The analysis of galaxy clustering measurements from surveys like Euclid or DESI is likely to be affected by the so called projection effects\, which causes the 1D marginals of the analysis to not contain the bestfit; this is a serious issue which can potentially harm the cosmological interpretation of these analyses. I will outline three complementary strategies to mitigate this bias: (i) simulation-calibrated priors\, (ii) a frequentist framework based on profile likelihoods\, and (iii) a Bayesian re-parameterisation that isolates degenerate directions. Applied to full shape data\, each method reduces the impact of projection effects. I will present the reduction of the projection effects for each technique when applied to DESI data. \nJoin Zoom Meeting\nhttps://lbnl.zoom.us/j/95679892182?pwd=RU5xU2dDRFNabnR1U3pQMklkYWFIdz09 \nMeeting ID: 956 7989 2182 \nPasscode: 169037
URL:https://rpm.physics.lbl.gov/event/speaker-marco-bonici-waterloo-title-taming-projection-effects-in-galaxy-clustering-analysis/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=UTC:20250703T120000
DTEND;TZID=UTC:20250703T130000
DTSTAMP:20260414T232941
CREATED:20250626T215823Z
LAST-MODIFIED:20250630T134410Z
UID:2869-1751544000-1751547600@rpm.physics.lbl.gov
SUMMARY:Speaker: Nicole Hartman (Technical University of Munich) - Title: b-tagging unlocks the Higgs Potential — deep learning for jet flavour tagging on ATLAS
DESCRIPTION:Research Progress Meeting \nDate: July 3\, 2025 \nTime: noon – 1:00 pm [note special time] \nLocation: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]  \nSpeaker: Nicole Hartman (Technical University of Munich) \nTitle: b-tagging unlocks the Higgs Potential — deep learning for jet flavour tagging on ATLAS \nAbstract: \nElectroweak symmetry breaking involves a Higgs potential that generates mass for the weak bosons. In the Standard Model\, this potential has a quartic form—but this is merely an ansatz that has yet to be experimentally verified. A first experimental probe of the Higgs potential could come from measuring the simultaneous production of two Higgs bosons (“di-Higgs”). This is an exceptionally rare process\, expected to require another decade of data collection to discover using current analysis methods. The most probable decay mode of a Higgs boson is into a pair of b-quarks\, which in turn produce b-jets in the detector. The channels driving di-Higgs sensitivity therefore all include b-jets in the final state. \nMachine learning is transforming many areas of life\, and particle physics is no exception. Because of the complexity of jets at the LHC\, b-jet classification (or flavour tagging) has become a leading application of deep learning in the field. This seminar presents the state-of-the-art in flavour tagging: a transformer model\, the same backbone architecture used in ChatGPT. These modern transformers deliver an impressive factor-of-four improvement in performance compared to earlier b-taggers based on recurrent neural networks. In addition\, transformers are more data-efficient\, allowing us to benefit from a tenfold increase in training statistics. Importantly\, these gains in simulation also translate to actual LHC data. \nTransformers are general-purpose architectures that can be integrated at multiple stages of the analysis pipeline. As training datasets continue to grow\, we can begin to view jet tagging as a foundation model for LHC physics—one that can be customized or “fine-tuned” for specific physics goals. We conclude by highlighting how an end-to-end optimizable analysis can fine-tune a jet-tagger for an HH physics search\, helping to further advance our di-Higgs program and quest to understand the Higgs potential. \n  \nJoin Zoom Meeting\nhttps://lbnl.zoom.us/j/98881011162?pwd=1kC2cSwdAjvJJUer0ymPMklwe8NFOE.1\n \nMeeting ID: 988 8101 1162 \nPasscode: 696672
URL:https://rpm.physics.lbl.gov/event/speaker-nicole-hartman-technical-university-of-munich-title-tba/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=UTC:20250710T160000
DTEND;TZID=UTC:20250710T170000
DTSTAMP:20260414T232941
CREATED:20250707T140406Z
LAST-MODIFIED:20250707T140406Z
UID:2882-1752163200-1752166800@rpm.physics.lbl.gov
SUMMARY:Speaker: Michael Reh (Boulder) - Title: Improving the Super-Kamiokande Analysis in the T2K Experiment
DESCRIPTION:Research Progress Meeting \nDate: July 10\, 2025 \nTime: 4:00- 5:00 pm \nLocation: This is a virtual event. Please see zoom link below.   \nSpeaker: Michael Reh (Boulder) \nTitle: Improving the Super-Kamiokande Analysis in the T2K Experiment \nAbstract: The Tokai-to-Kamioka (T2K) Experiment is a long baseline neutrino oscillation experiment located in Japan. T2K searches for muon neutrino disappearance and electron neutrino appearance oscillations at its far detector\, Super-Kamiokande (SK). When performing the T2K neutrino oscillation analysis\, the SK detector performance and reconstruction must be well understood in order to be certain of the number of muon and electron neutrino events observed. The T2K event reconstruction algorithm fiTQun does well to classify simulated electron and muon events in the detector\, however differences in reconstruction performance between simulated and real data events can bias the T2K analysis results. In this seminar\, the methods for estimating the T2K-SK detector reconstruction uncertainty will be discussed\, including significant upgrades that include events with multiple visible particle final states in the T2K-SK analysis for the first time. \nhttps://lbnl.zoom.us/j/98854322464?pwd=K2tKUm1VZjRlV1J5RHE3cXdHQzRxdz09 \nMeeting ID: 988 5432 2464\n\nPasscode: 142239
URL:https://rpm.physics.lbl.gov/event/speaker-michael-reh-boulder-title-improving-the-super-kamiokande-analysis-in-the-t2k-experiment/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=UTC:20250715T160000
DTEND;TZID=UTC:20250715T170000
DTSTAMP:20260414T232941
CREATED:20250709T230843Z
LAST-MODIFIED:20250709T231512Z
UID:2886-1752595200-1752598800@rpm.physics.lbl.gov
SUMMARY:Speaker: Regina Demina (U of Rochester) - Title: How Quantum Are Elementary Particles?  Exploring Entanglement and the Quest for Toponium
DESCRIPTION:Research Progress Meeting \nDate: July 15\, 2025 \nTime: 4:00- 5:00 pm \nLocation: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]  \nSpeaker: Regina Demina (University of Rochester) \nTitle: How Quantum Are Elementary Particles? Exploring Entanglement and the Quest for Toponium\n \nAbstract: While quantum mechanics underpins particle physics\, truly quantum effects are surprisingly difficult to establish in high-energy interactions. A rare exception comes from recent observations of quantum entanglement in top–antitop quark pairs by the ATLAS and CMS experiments. In certain regions of phase space\, these particles appear to lie outside the causality cone\, making the result even more intriguing. In this talk\, I will review the details of these groundbreaking measurements\, their implications\, and potential criticisms. Some deviation in the observed level of correlation between top and antitop quarks resulted in an exciting discovery of toponium\, a bound state of top and antitop quarks observed by CMS. Recently confirmed by Atlas\, toponium is the heaviest known composite particle\, with a mass of 343 GeV—surpassing even the heaviest nucleus\, Oganesson\, at 279 GeV. \nJoin Zoom Meeting\nhttps://lbnl.zoom.us/j/95679892182?pwd=RU5xU2dDRFNabnR1U3pQMklkYWFIdz09 \nMeeting ID: 956 7989 2182 \nPasscode: 169037
URL:https://rpm.physics.lbl.gov/event/speaker-regina-demina-u-of-rochester-title-how-quantum-are-elementary-particles-exploring-entanglement-and-the-quest-for-toponium/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=UTC:20250724T160000
DTEND;TZID=UTC:20250724T170000
DTSTAMP:20260414T232941
CREATED:20250717T172256Z
LAST-MODIFIED:20250717T172256Z
UID:2898-1753372800-1753376400@rpm.physics.lbl.gov
SUMMARY:Speaker: Alex Wang (UCSC) - Title: Searching for di-Higgs production with the bbγγ final state: early Run 3 and beyond
DESCRIPTION:Research Progress Meeting \nDate: July 24\, 2025 \nTime: 4:00- 5:00 pm \nLocation: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]  \nSpeaker: Alex Wang (UCSC) \nTitle: Searching for di-Higgs production with the bbγγ final state: early Run 3 and beyond \nAbstract: Since the discovery of the Higgs boson by the ATLAS and CMS experiments in 2012\, many of its properties have been constrained by precision measurements using LHC Run 2 data. One notable exception is the Higgs self coupling lambda\, which modifies the shape of the Higgs potential and\, in the Standard Model\, is completely determined by the Higgs mass and vacuum expectation value. A value of lambda different from the Standard Model prediction could have profound implications for particle physics and cosmology. The simultaneous production of two Higgs bosons (di-Higgs)\, is the most accessible way to study this coupling at the LHC but presents experimental challenges due to its low production cross-section\, about three orders of magnitude smaller than that of single Higgs.\nIn this talk\, I will present the latest ATLAS search for di-Higgs production with the bbγγ final state\, in which one Higgs decays into a pair of b-quarks and the other decays into a pair of photons. This is one of the most experimentally powerful channels due to the high H->bb branching ratio and the excellent ATLAS photon resolution. With the inclusion of the Run 2 (2015 – 2018) and early Run 3 (2022 – 2024) LHC datasets\, these new results constitute both the first ATLAS result using over 300ifb of data and also the world’s best single-channel di-Higgs constraints to-date. Finally\, I will discuss the latest prospects for the High Luminosity LHC\, which is expected to increase the dataset by over a factor of 10 and bring us within observation of di-Higgs production. \nhttps://lbnl.zoom.us/j/98854322464?pwd=K2tKUm1VZjRlV1J5RHE3cXdHQzRxdz09 \nMeeting ID: 988 5432 2464\n\nPasscode: 142239
URL:https://rpm.physics.lbl.gov/event/speaker-alex-wang-ucsc-title-searching-for-di-higgs-production-with-the-bb%ce%b3%ce%b3-final-state-early-run-3-and-beyond/
END:VEVENT
END:VCALENDAR