All future and past seminars

SPRING semester 2020


Feb 26 : Dr Michele Punturo, INFN Perugia
Title : GW and Einstein telescope


Mar 11  : Dr Werner Lustermann, ETH
Title : SAFIR


Mar 25 : Dr Elena Cuoco, SNS Pisa
Title : ML & Gravit Waves


Apr 01 : Dr Anatael Cabrera, APC, Paris
Title : Opaque Detectors


Apr 22 : Dr Marie-Helene Genest, LPSC, Grenoble
Title : LHC Exotics overview


Apr 29 : Dr Andreas Hoecker, CERN
Title : G-2


May 13 : Dr Max Swiatlowski, TRIUMF
Title : Physics with H->bb at the LHC


Jun 10 : Prof. Tae Ming Hong, Pittsburg University
Title : VBF Higgs searches at the LHC




AUTOMN semester 2019


Sep. 25 : Prof. Susanne Mertens, TU, Munich
Title : First neutrino mass results from KATRIN - Access to the talk


The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly probe the neutrino mass with a sensitivity of 0.2 eV (90% CL).

KATRIN persues a model-independent approach, solely based on the kinematics of tritium beta decay. A non-zero neutrino mass manifests itself as a small spectral distortion close to the endpoint of the decay. In spring 2019 KATRIN performed its first neutrino mass measurement campaign. With this first data set new limits on the neutrino mass could be established, reaching for the first time the sub-eV regime. In this talk the KATRIN working principle and the first neutrino mass results will be presented. A short perspective to the future scientific program of KATRIN will be given.


Oct 02 : Prof. Andrea Wulzer, University of Padova & CERN - Access to the talk
Title : Present and Future Colliders Physics


High-energy colliders are indispensable tools for a broad, systematic and robust exploration of Fundamental Interactions Physics. One such collider, the LHC including its high-luminosity upgrade (HL-LHC), will deliver data during the next several decades. I will illustrate by concrete examples the HL-LHC potential to probe presently unexplored new physics. I will also outline some of the exciting challenges in theoretical and experimental physics, and in data analysis, that will have to be addressed in order to exploit this potential fully. Finally I will summarise some aspects of the physics potential of future collider projects like the FCC, CLIC and ILC, and of more speculative proposals such as the muon collider.


Oct 16 : Prof. Marcello Messina, NYU, Abu Dhabi
Title : The PTOLEMY project: from an idea to a real experiment to detect the Cosmological Relic Neutrinos - Access to the talk


In the first part the seminar a novel idea on the detection of Cosmological Relic Neutrinos (CRN) and more in general, on the detection of neutrinos of vanishing energy will be presented. This idea is described in detail in the paper [1]. The method is based on the fact that neutrino interactions on beta-instable nuclei have the key feature of requiring no energy threshold for the neutrino interaction. Some phenomenological aspects will be presented.

The second part of the seminar will be dedicated to the PTOLEMY project, in a starting phase at the Laboratori Nazionali del Gran Sasso, Italy. In this project we aim at demonstrating the detection principle of the CRN and finalize the design of the future full scale experiment. The technologies on which the detector concept is based will be presented and the key features explained.

A new-concept of electrostatic filter discussed in a paper [2] recently published by the PTOLEMY collaboration will also be explained in details.


Oct 30 : Dr Marco Apollonio, Diamond Light Source, UK
Title : Synchrotron Radiation: a bright light for science


Diamond Light Source is the UK’s national synchrotron science facility, located at the Harwell Science and Innovation Campus in Oxfordshire. The machine accelerates electrons to near light speeds so that they give off light 10 billion times brighter than the sun. These bright beams are then directed off into laboratories known as ‘beamlines’. Here, scientists use the light to study a vast range of subject matter, from new medicines and treatments for disease to innovative engineering and cutting-edge technology. Whether it’s fragments of ancient paintings or unknown virus structures, at the synchrotron, scientists can study their samples using a machine that is 10,000 times more powerful than a traditional microscope.

I will illustrate the main characteristics of the light produced at Diamond, the way it is generated by means of dedicated devices and the techniques used to improve the quality of such radiation by a substantial reduction of size and divergence of the electron beams. I will show a comparison of the different solutions adopted in present and (near) future machines and conclude with few science cases related to the use of synchrotron radiation at our facility.


Nov 06 : Dr Nathal Severijns, KU, Leuven University
Title : Probing physics beyond the Standard Model in neutron and nuclear beta decay- Access to the talk


Precise measurements of observables in beta decay allow testing the symmetries of the Standard Model, or searching for new physics at the low-energy frontier. Such measurements provide information on physics beyond the Standard Model that is complementary to direct searches at the Large Hadron Collider.

The main challenges in order to further improve the sensitivity to new physics are to reach per mil precision levels and possibly beyond, while keeping control over systematics and small Standard Model effects that then start playing a role. 

A non-exhaustive overview of this field and future prospects will be presented based on selected, recent and planned state-of-the-art measurements that use a variety of techniques.


Nov 20 : Prof. Kostas Nikolopoulos, University of Birmingham
Title : NEWS-G: Search for Light Dark Matter with a Spherical Proportional Counter - Access to the talk


The NEWS-G collaboration is searching for light dark matter candidates using a spherical proportional counter. Access to the mass range from 0.1 to 10 GeV is enabled by the combination of low energy threshold, light gaseous targets (H, Ne), and highly radio-pure construction.  

 The current status of the experiment will be presented, along with the first NEWS-G results obtained with SEDINE, a 60 cm in diameter spherical proportional counter operating at LSM (France), excluding cross-sections above 4.4x10^{37} cm^2 for 0.5 GeV WIMP using a neon-based gas mixture.  

 The construction of the next generation, 140 cm in diameter, spherical proportional counter constructed using 4N copper at LSM will be discussed, along with the latest advances in SPC instrumentation. The detector, following initial commissioning at LSM is currently being transported to SNOLAB (Canada), with the first physics run scheduled for 2020. Finally, future prospects and applications of spherical proportional counters will be summarised.



Dec 04 : Dr Giovanni Rumolo, CERN
Title : LHC Injectors Upgrade Project: Towards New Territory Beam Parameters - Access to the talk


The LHC Injectors Upgrade (LIU) project aims at increasing the intensity and brightness in the LHC injectors in order to match the challenging requirements of the High-Luminosity LHC (HL-LHC) project, while ensuring high availability and reliable operation of the injectors complex well into the HL-LHC era. This requires extensive hardware modifications and new beam dynamics solutions in the entire LHC proton and ion injection chains: the new Linac4, the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS), the Super Proton Synchrotron (SPS), together with the ion PS injectors (the Linac3 and the Low Energy Ion Ring (LEIR)). All hardware modifications are being implemented during the 2019-2020 CERN accelerators shutdown.

A view on the future operation of the LHC injectors is also presented, highlighting the benefits in terms of beam parameters for both the LHC beams and those for fixed target physics.


Dec 11 : Dr Anna Soter, PSI
Title : Fundamental physics with muons: from the proton radius to antimatter gravity - Access to the talk

At the Paul Scherrer Institute ongoing precision experiments involving muons and muonic atoms are targeting fundamental questions in flavor physics, probing the symmetries of the Standar Model, and measuring fundamental constants. In this talk these ongoing precision efforts will be introduced by concentrating on a newly proposed experiment to measure gravitational interaction of muonium (Mu). 
Carrying out a direct gravity experiment on Mu atoms would be of fundamental interest. Such a measurement would provide an exotic test of the weak equivalence principle, since the positive muon that dominates the Mu mass is an elementary antimatter particle, and also a lepton from  the second generation. 

To make this experiment possible, we are investigating methods to create a novel Mu source based on conversion in  superfluid helium (SFHe). The unique chemical properties of SFHe may allow the production of a high brightness atomic Mu beam in vacuum. A high quality atomic beam would then benefit next generation precision laser spectroscopy experiments, and would make intertial measurements in an atom interferometer feasible. The promising preliminary results on cold Mu production and the feasibility of a Mu interferometer.


Jan 15 : Paola Villa, University Wisconsin- Madison
Title : Romancing the CERN: Constructive Interferences between Physics and Literature - Access to the talk


Physics and literature make odd bedfellows. More than 60 years after the famous C.P. Snow’s anathema sanctioning the incommunicability between the sciences and the humanities, the debate on the two cultures is still very much alive. Studies in the field of Literature and Science flourished in the past 20 years. The humanities, in general, have become increasingly aware of the important contribution of scientific ideas into shaping modern cultures and artistic productions. Yet, there still seems to be a fundamental asymmetry between literature’s understanding of physics and physics’ reception of literature. When confronted with the idea of what literature can do for science, the answer has been as much unanimous as reductive: “storytelling”. Is it really the case that all literature has to offer is a series of narrative tricks?

Drawing from examples of novels written by physicist and literary authors alike, I will explore some of the mechanisms that emerge at the crossroads of the two disciplines. What happens when the experimental apparatus of physics becomes the centerpiece of a fictional account? How does the material culture of detectors and particle accelerators influence the construction of a novel? And conversely, what tools does fiction offer to scientists in order to explore their ideas and their social environment? The goal of this presentation is not to discount the important lesson of “storytelling”, but rather to offer additional reasons why scientists, and physicists in particular, might want to pay more attention to literature.



SPRING semester 2019


Jan. 30 : Prof Francesco RIVA, Université de Genève, DPT - Access to the talk
Title : Higgs Couplings without the Higgs


The measurement of Higgs couplings constitutes an important part of present Standard Model precision tests at colliders. In this article, we show that modifications of Higgs couplings induce energy-growing effects in specific amplitudes involving longitudinally polarized vector bosons, and we initiate a novel program to study these very modifications of Higgs couplings off-shell and at high-energy, rather than on the Higgs resonance. Our analysis suggests that these channels are complementary and, at times, competitive with familiar on-shell measurements; moreover these high-energy probes offer endless opportunities for refinements and improvements.


Fev. 27  : Dr Jamie BOYD, CERN - Access to the talk
Title : Looking forward to new physics: the FASER experiment


The goal of the FASER experiment is to search for new light, weakly-interacting particles at CERNs Large Hadron Collider. By exploiting a unique location underground in the CERN tunnel system, FASER will provide world-leading sensitivity in a relatively small, quick, and inexpensive experiment. The FASER detector is currently under construction to be installed into the tunnel during 2020 in LHC Long Shutdown 2. This seminar will describe the physics motivations, detector design, and expected performance of FASER as well as the physics prospects.



Mar. 6 :  Dr Edda GSCHWENDTNER, CERN - Access to the talk
Title : AWAKE : Accelerating electrons to GeVs in a proton driven plasma wakefield experiment


AWAKE is an accelerator R&D experiment at CERN to demonstrate for the first time ever plasma wakefield acceleration of electrons in wakefields driven by a proton bunch and, in the future, take advantage of the large energy store in the proton bunch to reach very high energy gain in a single plasma.

 In 2016/2017 AWAKE has achieved a major milestone and observed the strong modulation of high-energy proton bunches in plasma; the results represent the first ever demonstration of strong plasma wakes generated by proton beams. In May 2018 AWAKE demonstrated for the first time the acceleration of externally injected electrons to multi-GeV energy levels in the proton driven plasma wakefields, a result recently published in Nature

 The aims of AWAKE Run 2 (2021 - 2024) are to achieve high-charge bunches of electrons accelerated to high energy, about 10~GeV, while maintaining beam quality through the plasma and showing that the process is scalable. The final goal by the end of AWAKE Run 2 is to be in a position to use the AWAKE scheme for particle physics experiments. 

 An introduction to plasma wakefield acceleration is given.  AWAKE experiment is described. The recent results are shown. The design and challenges of AWAKE Run 2 are presented. Particle physics experiments based on the AWAKE acceleration scheme are introduced. 


Mar. 13 : Prof. Holger FRÖNING, Heidelberg University - Access to the talk
Title : An Efficient Reduce-and-Scale Architecture for DNN-based Inference on Resource-Constrained Systems


While Deep Learning is becoming ubiquitous in computing, being deployed in systems ranging from data centers to mobile devices, its computational complexity is huge. Contrary, while resource-constrained systems steadily improve their processing power, there is a huge gap to the demands of deep neural networks. Furthermore, CMOS technology projections show that performance scaling will be increasingly difficult, due to reasons including power consumption and eventually limited component scaling.

In the DeepChip collaboration, we gear to design software architectures that improve the mapping of DNNs to resource-constrained systems. In this talk, we will shortly review basics and recent related work, before we introduce the main concept of DeepChip, which is based on a reduce-and-scale architecture and allows to remove redundancies found in typical DNNs, thereby allowing an improved deployment on mobile or embedded systems. We will conclude with a couple of anticipated research directions.


Mar. 20 :  Prof. Marco ZANETTI, Padova University - Access to the talk
Title : Prospects for a Muon Collider to probe the Energy Frontier


Using muons as probes exceeding the energy scale reached by the LHC is a tantalising idea. A Muon Collider would in fact have a unique physics potential, making such a machine a dream for the HEP community. Will this dream ever become reality depends on whether the numerous technological challenges posed by the project will be overcome. Several schemes have been proposed in the years, all addressing in different ways key issues such as the production of high brilliance muon beams, its acceleration and the management of the beam induced radiation. In this seminar, after some (obvious) considerations supporting the physics case, I will review the studies performed so far and latest developments on the various project's components. I will focus in particular on the recent proposal of a positron induced low emittance muon source (LEMMA) and the required R&D to prove its feasibility.


Apr. 17 :  Dr Merlin KOLE, Université de Genève, DPNC - Access to the talk
Title : POLAR: The first detailed polarization measurements of the brightest explosions in the Universe


Gamma-Ray Bursts (GRBs) are the most violent explosions in the Universe since the Big Bang. These events, which despite occurring millions or even billions of light years away, are observed approximately once per day. Some are thought to be the result of the death of very massive stars while, thanks to gravitational wave measurements, a subset was recently shown to be the result of the merging of 2 neutron stars. The extreme brightness of these events allowed them to be discovered by accident more than 50 years ago by some of the first gamma-ray detectors operating in space. While since then great progress was made in our understanding of these events through studies of the arrival time, direction and energy of the gamma-rays emitted in these explosions, many open questions remain and appear difficult or even impossible to be answered using conventional studies. In recent decades theoretical studies have indicated that a wealth of information is contained in the one remaining unmeasured parameter of these photons: their polarization.

The POLAR instrument was designed specifically to provide the first detailed polarization measurements of GRBs. POLAR was developed by a collaboration of institutes in Switzerland, Poland and China, and launched in September 2016 as part of the second Chinese space lab, the Tiangong-2. It took data for a total of 6 months during which it detected a total of 55 GRBs as well as several other astrophysical objects. The complicated polarization analysis of 5 of these GRBs was recently completed. The results indicate that the polarization is more complicated than any of the existing models suggest. During this talk I will provide an introduction to GRB astrophysics, discus the history of the POLAR mission and present the first results of this mission and their interpretation (or at least explain the lack thereof).


May 15 :  Prof. Pawel MOSKAL, Jagiellonian University, Krakow, Poland - Access to the talk
Title : Positronium in physics and medicine


Positronium, the lightest purely leptonic object decaying into photons, is known as an excellent laboratory for fundamental physics studies. It can also be useful for medical diagnostics since during the routine positron emission tomography about 40% of positrons annihilation occurs through the creation of positronium atoms which properties change and vary depending on the size of the intermolecular voids and concentrations of bio-active molecules.

 The newly constructed Jagiellonian Positron Emission Tomograph (J-PET) is the first PET scanner built from plastic scintillators. It is a world unique apparatus enabling measurement and imaging of positronium properties and studies of the quantum entanglement of photons originating from positronium annihilations.

 In the talk we will discuss the recently proposed method of positronium imaging of the human body and possibilities to use properties of positronium atoms such as (environment modified) lifetime or entanglement of photons produced in positronium annihilation as diagnostic biomarkers for cancer therapy.

 We will also present the capability of the J-PET detector to improve the current precision of testing CP, T and CPT symmetries in the decays of positronium atoms and report on results from the first data-taking campaigns.


May 22 : Dr Graeme STEWART, CERN - Access to the talk
Title :
Meeting Future Software Challenges in High-Energy Physics


The computing hardware of today is vastly different to what was available when the LHC experiments began writing their software, almost 20 years ago. Single CPU cores with ever faster clocks have given way to multi-core chips with wide vector registers for parallel processing. At the same time, Graphics Processing Units (GPUs) have become ever more powerful and ever more popular, offering thousands of cores and raw floating point performance much greater than CPUs can manage. This presents two huge challenges to HEP software. The first is concurrency, the adaption to performing many tasks in parallel during data processing. The second is heterogeneity, where instead of a mono-culture of x86_64 processors, HEP needs to adapt to a mixture of different CPU architectures, GPUs and even more exotic processors, such as FPGAs. These challenges from modern hardware come just at the time when planning for the High-Luminosity LHC foresees a x10 increase in rate for ATLAS and CMS and a tremendous jump in event complexity, with pile-up perhaps reaching 200.


To face these challenges computing and software experts from multiple experiments and institutions came together in 2015 to begin a bottom-up organisation to tackle the challenges of the coming years and to avoid each experiment having to work alone to solve these problems. The HEP Software Foundation (HSF) undertook to organise the community to write a Community White Paper Roadmap, where more than 300 physicists and computing experts came together to map out a plan for progress from event generation through to final analysis. Solution areas, like machine learning, were put forward as major pieces of that strategy for the future.  Since the CWP publication many HSF working groups have begun tacking the pressing issues we face, with an emphasis always on cross-experiment work and common solutions. In this seminar I will describe the genesis of the HSF and the process that led to the Community White Paper. I will review key areas where the HSF is helping to find effective solutions to problems in HEP computing. Finally, I will end on the question of how we argue for more resources to fund software in the future and best work together as a community with other data intensive sciences and industry.




Département de Physique Nucléaire et Corpusculaire | 2017 | Impressum.