{"id":1576,"date":"2025-02-14T10:14:57","date_gmt":"2025-02-14T09:14:57","guid":{"rendered":"https:\/\/eppg.ugent.be\/?page_id=1576"},"modified":"2025-04-11T08:32:30","modified_gmt":"2025-04-11T07:32:30","slug":"2024-2025","status":"publish","type":"page","link":"https:\/\/eppg.ugent.be\/index.php\/2024-2025\/","title":{"rendered":"2024-2025"},"content":{"rendered":"\n
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The seminar series are funded by the
Flemish Government and
UGent Doctoral School.<\/p>\n<\/div>\n\n\n\n

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Starting in academic year 2013\/2014, the research group hosts a regular series of seminars, dedicated to our wide audience that includes physicists, students and engineers. These seminars feature excellent overviews presented by distinguished speakers and provide high value educational material for students . They prove to be the optimal venue for fruitful discussions between external experts and the group members.<\/span> These seminars organised with the support of the Flemish Government. and UGent Doctoral Schools<\/em>.<\/p>\n\n\n\n

The program for academic year 2024-2025 can be found below:<\/span><\/em> <\/p>\n\n\n\n



April 29th, 2025<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, meeting room, ground floor)<\/p>\n\n\n\n

Speaker: Rahul Nigam\u00a0(BITS Hyderabad, India)<\/strong><\/p>\n\n\n\n

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Aspects of Maximal Hypersurfaces and the Volume of Black Hole<\/u><\/strong><\/strong><\/strong><\/strong><\/strong>s\u00a0<\/strong><\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

In recent years, the interior volume of black holes\u2014particularly as formulated by Christodoulou and Rovelli\u2014has offered a fresh geometric perspective on the evolving nature of black hole interiors. In this talk, I present our extension of this framework to the case of rotating BTZ black holes in (2+1)-dimensional spacetime and Kerr black holes in 3+1 dimensions.
I will also share my thoughts on the possibility of\u00a0 further investigating the connection between black hole interior volume and quantum complexity which has been proposed by Susskind. By comparing volume growth with complexity evolution, one can test the “Complexity = Volume” proposal for a family of black holes.<\/p>\n<\/blockquote>\n\n\n\n



April 22th, 2025<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, meeting room, ground floor)<\/p>\n\n\n\n

Speaker: Matei Climescu (University of Mainz, Germany)<\/strong><\/p>\n\n\n\n

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Development of high-precision calorimeters for the SHiP experiment at CERN SPS<\/span><\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/p>\n\n\n\n

SHiP (Search for Hidden Particles) is an approved experiment to be located in the North Area at CERN which will utilize unprecedented proton fluxes in a beam dump configuration to probe the intensity frontier to search for new physics. SHiP will be equipped with two calorimeter systems. The SHiP Scattering Neutrino Detector will leverage its high granularity calorimetric layers to perform energy reconstruction and particle identification in neutrino events, particularly the O(10\u2074) expected tau neutrino events, as well as light dark matter searches. The second calorimeter is based on the novel SplitCal concept and will be part of the Hidden Sector Decay Spectrometer. It will enable downstream particle identification and reconstruction of neutral final states using high-precision detector layers. Together with segmentation of the calorimeter, high precision layers will allow to achieve excellent angular resolution, translating to high reconstruction efficiency and mass resolution in the search for feebly interacting beyond the Standard Model particles, such as axion-like-particles, heavy neutral leptons and sgoldstinos. The High granularity layers would involve scintillator tiles readout with optical fibres and SiPMs derived from the SoLid experiment whereas the GEM detectors would be utilised as High Precision Layers. These proposed detectors will allow the SHiP experiment to extend its sensitivity to beyond the standard model physics.
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February 27th, 2025<\/h3>\n\n\n\n

(14:00, Campus Sterre \u2013 S8, lecture room 0.1)<\/p>\n\n\n\n

Speaker: Maciej Bilicki<\/strong>\u00a0(Polish Academy of Sciences, Poland)<\/strong><\/p>\n\n\n\n

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Weak gravitational lensing as seen by the Kilo-Degree Surve<\/strong><\/strong><\/strong><\/strong><\/strong><\/span>y <\/strong><\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

The large-scale structure (LSS) of the Universe is a rich source of cosmological information. Among the key probes using the LSS is the weak gravitational lensing \u2013 small distortions of observed shapes of distant galaxies resulting from light-rays being bent by the cosmic gravitational field. The cosmological weak lensing signal \u2013 so called cosmic shear \u2013 allows us to measure the amount of all types of matter \u2013 both luminous and dark \u2013 as well as its \u201cclumpiness\u201d quantifying the growth of structure. I will describe the key results from one of the major weak lensing experiments of today \u2013 the Kilo-Degree Survey (KiDS) of the European Southern Observatory. I will also present how we combine the cosmic shear from distant galaxies with the distribution of foreground \u201clenses\u201d into multi-probe analyses, giving us access not only to cosmological constraints, but also to the connection between properties of galaxies and their luminous and dark matter content.
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February 25th, 2025<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, meeting room, 1st floor)<\/p>\n\n\n\n

Speaker: Maria Lisa Brozzetti<\/strong> (University of Perugia, Italy)<\/strong><\/p>\n\n\n\n

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Mimicking the SF evolution <\/strong><\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

Studying the density distribution of galaxies in UpGLADE, the upcoming huge galaxy catalog from non-independent surveys, it\u2019s possible to observe a not yet investigated behavior in the bright end of the Luminosity function, also known as the Schechter function. Going at higher redshifts the bright end seems to evolve. The evolution of the SF from a single catalog is studied in literature, but our purpose is check if the redshift uncertainties ( now calibrated with a Gaussian distribution) could be a significant source  of error in the UpGLADE luminosity function – mimicking its evolution – and to extrapolate and to test other possible biases. On the other hand, managing a large and heterogeneous amount of observables from different facilities with different limits, suggests us to have a simulated model to compare with. Two mock catalogs and their main ingredients are illustrated: MICEcatv1 and IllustrisTNG. We will see their properties and some preliminary results of this ongoing project.<\/p>\n\n\n\n

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February 4th, 2025<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, seminar room, 1st floor)<\/p>\n\n\n\n

Speaker: Nicholas Kamp<\/strong> (Harvard <\/strong>University, USA)<\/strong><\/strong><\/p>\n\n\n\n

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Heavy Neutrinos in Ice, Water, Plastic, and Dirt<\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

From the continuous energy spectrum of beta decay electrons to the disappearance of neutrinos from the Sun and the atmosphere, experimental anomalies have catalyzed progress in neutrino physics since the 1930s. One of the longest-standing anomalies in the neutrino sector is the 4.8\ud835\udf0e excess of electron-like events observed by the MiniBooNE experiment at Fermilab. This talk discusses a promising solution for the excess: heavy neutral leptons (HNLs) with a transition magnetic moment coupling to Standard Model neutrinos. We derive phenomenological constraints on these dipole-portal HNLs using data from the plastic scintillator tracking detector of MINERvA and the gaseous argon time projection chambers of ND280. Next, we discuss a novel search for “double cascades” from dipole-portal HNLs at the South-Pole-based IceCube and Mediterranean-Ocean-based KM3NeT observatories. We further examine the sensitivity of these neutrino telescopes to the minimal heavy neutral leptons that appear in Type I Seesaw models of neutrino mass. Finally, we introduce two new experimental concepts that take advantage of natural environment surrounding the Large Hadron Collider (LHC) to collect large samples of collider-generated neutrinos: SINE, which observes neutrino interactions in bedrock, and UNDINE, which observes neutrino interactions in Lake Geneva. Due to the high energy scale of LHC-generated neutrinos, these experiments can perform novel searches for minimal HNLs and constrain the forward production of charmed hadrons in proton-proton collisions. The latter of these has important implications for investigations into the origin of cosmic neutrinos at IceCube, KM3NeT, and beyond.<\/p>\n\n\n\n

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December 6th, 2024<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, lecture room, 2nd floor)<\/p>\n\n\n\n

Speaker: Alessandro Vicini<\/strong> (Universit\u00e0 degli Studi di Milano, Milan, Italy)<\/strong><\/strong><\/p>\n\n\n\n

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Precision electroweak physics at the LHC<\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

The large amount of high-quality data collected at the LHC will bring the experimental error of several observables at the per mille level, also in the TeV mass range. The combination of this information, together with the precision studies of W and Z bosons properties, will allow a very severe test of the Standard Model. I will illustrate recent results about the determination of the W boson mass, of the weak mixing angle and about the study of the large mass tails of the Drell-Yan distributions, with the associated theoretical challenges.<\/p>\n\n\n\n

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December 3th, 2024<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, Room 2.01)<\/p>\n\n\n\n

Speaker: Uddeepta Deka<\/strong> (ICTS Bangalore, India)<\/strong><\/p>\n\n\n\n

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Microlensing of gravitational waves: prospects and challenges<\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

Gravitational lensing of gravitational waves (GWs) offers a compelling opportunity to investigate the spacetime geometry in the vicinity of the lens. In this talk, we look into the effects of lensing-induced diffraction modulations in the GW signal and the prospects of constraining the lens parameters. Parameter inference of the lensed waveforms requires the template generation for these modulated signals to be computationally expeditious. We introduce a method founded on a ‘greedy algorithm’ for rapidly generating microlensed GW signals, tailored to astrophysically relevant lens models.<\/p>\n<\/blockquote>\n\n\n\n


November 13th, 2024<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, Room 2.01)<\/p>\n\n\n\n

Speaker:  Santiago Casas (RWTH Aachen University, Germany).<\/strong><\/p>\n\n\n\n

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Towards a robust exploration of the Dark Sector with Euclid and Stage-IV surveys<\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

The next generation of galaxy surveys\u2014Euclid, LSST, DESI, Nancy Roman, SKAO\u2014will deliver unprecedented precision in mapping the large-scale structure (LSS) of the Universe. These datasets will probe the expansion rate, non-linear structure growth, and the cosmic matter-energy budget, providing new insights into Dark Matter, Dark Energy, and persistent tensions in parameters like H0 and S8. Modified Gravity models, including f(R) and scalar field theories, will be rigorously tested, and next-generation galaxy surveys, in combination with current and upcoming CMB experiments, will reveal details about the composition of cosmic components and primordial fluctuations. Cross-correlations, such as those between optical and radio cosmology via 21cm intensity mapping, will enhance these efforts, providing better constraints but also creating new challenges in the modeling of systematics. Achieving robust results in the study of the Dark Sector requires addressing degeneracies such as massive neutrinos and baryonic feedback. I will discuss how the Euclid collaboration is integrating these factors into its photometric and spectroscopic likelihoods, using both machine learning methods like emulators and semi-analytic models like effective field theory of LSS to perform detailed forecasts for upcoming data analyses. I will also discuss ongoing work in provable computations and differentiable programming, which can improve the robustness and efficiency of our analysis.<\/p>\n\n\n\n

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October 29th, 2024<\/h3>\n\n\n\n

(11:00, Campus Proeftuin (INW) \u2013 N3, Room 2.01)<\/p>\n\n\n\n

Speaker:  Laurids Jeppe (DESY, Germany).<\/strong><\/p>\n\n\n\n

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Searching for new scalars, pseudoscalars and tt\u0305 bound states at CMS<\/strong><\/strong><\/strong><\/span><\/strong><\/p>\n\n\n\n

I will present a search for heavy pseudoscalar or scalar bosons decaying to a top quark pair (tt\u0305) in final states with one or two charged leptons, using 138\/fb of proton-proton collisions at \u221as = 13 TeV recorded by the CMS experiment. The invariant mass of the reconstructed $t\\bar{t}$ system and variables sensitive to its spin state are used to discriminate against the standard model tt\u0305 background and to infer spin quantum numbers. An excess of the data above the background prediction, as modeled using perturbative quantum chromodynamics (QCD) only, is observed with a significance of above five standard deviations. I will discuss three possible hypotheses to interpret the excess, which is located close to the tt\u0305 production threshold: by production of an additional scalar or pseudoscalar boson, or by the existence of a color singlet pseudoscalar tt\u0305 bound state, as predicted in a simplified model of nonrelativistic QCD. For the first two hypotheses, I will outline upper limits on the coupling of pseudoscalar or scalar bosons to top quarks in a mass range of 365\u20131000 GeV and relative widths of 0.5\u201325%. For the third scenario, I will present and discuss an extracted cross section of 7.1 pb with an uncertainty of 11%.<\/p>\n<\/blockquote>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

The seminar series are funded by theFlemish Government andUGent Doctoral School. Starting in academic year 2013\/2014, the research group hosts a regular series of seminars, dedicated to our wide audience that includes physicists, students and engineers. These seminars feature excellent overviews presented by distinguished speakers and provide high value educational material for students . They […]<\/p>\n","protected":false},"author":5,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1576","page","type-page","status-publish","hentry"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/pages\/1576","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/comments?post=1576"}],"version-history":[{"count":10,"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/pages\/1576\/revisions"}],"predecessor-version":[{"id":1707,"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/pages\/1576\/revisions\/1707"}],"wp:attachment":[{"href":"https:\/\/eppg.ugent.be\/index.php\/wp-json\/wp\/v2\/media?parent=1576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}