Contact
Name
Andrea Giammanco
Position
Professor
Email
andrea.giammancclouvain.be
Address
Centre for Cosmology, Particle Physics and Phenomenology - CP3
Université catholique de Louvain
2, Chemin du Cyclotron - Box L7.01.05
B-1348 Louvain-la-Neuve
Belgium
Phone
+32 10 47 3221
Office
My personal homepage
UCL member card
People responsibilities
Postdocs
Hamed Bakhshiansohi (MOVE-IN), member since January 2016
My main interest is to search for top-Higgs anomalous couplings in single-top plus Higgs events, where the Higgs boson decays to two photons using the CMS experiment data. This is the only process that can determine the relative sign of the Higgs boson couplings to other bosons and fermions, at the leading order. The Higgs boson’s decay to photons is expected to have the highest sensitivity among other Higgs decay modes, as the branching ratio of the H→γγ also changes by modifying the Higgs couplings to top-quark and W-boson.

Pieter David (FNRS), member since February 2016
Experimental particle physicist, member of the CMS collaboration. Currently working on measurements of processes involving top quarks in order to constrain higher-order EFT operators.

PhD students
Georgios Konstantinos Krintiras (UCL-FSR), member since February 2015
Experimentalist in the realm of the CMS experiment at LHC, Geneva. I am studying processes involving single top quarks which provide direct probes of electroweak interactions. The second (2015-2018) operational period of LHC, with an expected luminosity of at least four times greater than its first round, will boost the sensitivity of the associated production of single top quarks with Higgs bosons. Such a process offers a stringent test for the SM predictions and serves as an excellent opportunity for identifying departures from this standard picture. Also, I am performing studies within fast detector simulations, i.e. in the context of CMS FastSim.

Sophie Wuyckens (FNRS), member since July 2017
Development of a compact and portable gaseous detector for "muography", i.e. imaging with cosmic rays. Data analysis in the CMS experiment.

Research statement
Broadly speaking, I am interested into:

# Analysis of CMS data at LHC; more specifically:
* Top quark physics: the sixth quark is quite unusual (who ordered that 175 GeV monster?). Could it be the key to unlock the mystery of what's beyond the Standard Model? I have been recently (Sep.2014-Aug.2016) leading the CMS group devoted to that.
* Higgs boson couplings (with the top quark and with new particles): being the last particle to have been discovered, and by far the most crucial of them all, it is rather natural to check if that famous 125 GeV resonance tells us something that we did not expect. Since Jan.2018, I am one of the coordinators of the work package "Higgs coupling determination and interpretation" of the be.h Belgian HEP consortium.
* Unusual signatures of new physics: our multi-purpose detectors were optimized for as many interesting signatures as possible, but I like when someone proposes original ways to use them, that can actually cover some blind spot of traditional searches.
# Muography, i.e., the application of HEP detectors and techniques for mapping the interior of large structures using atmospheric muons from cosmic ray showers.
# Parametric HEP detector simulations.
# Some forays into HEP phenomenology, in collaboration with theorists.
# Applied statistics (machine learning, unfolding, etc.)
Projects
I am involved in the following research directions:

Advanced Multi-Variate Analysis for New Physics Searches at the LHC

With the 2012 discovery of the Higgs boson at the Large Hadron Collider, LHC, the Standard Model of particle physics has been completed, emerging as a most successful description of matter at the smallest distance scales. But as is always the case, the observation of this particle has also heralded the dawn of a new era in the field: particle physics is now turning to the mysteries posed by the presence of dark matter in the universe, as well as the very existence of the Higgs. The upcoming run of the LHC at 13 TeV will probe possible answers to both issues, providing detailed measurements of the properties of the Higgs and extending significantly the sensitivity to new phenomena.

Since the LHC is the only accelerator currently exploring the energy frontier, it is imperative that the analyses of the collected data use the most powerful possible techniques. In recent years several analyses have utilized multi-variate analysis techniques, obtaining higher sensitivity; yet there is ample room for further improvement. With our program we will import and specialize the most powerful advanced statistical learning techniques to data analyses at the LHC, with the objective of maximizing the chance of new physics discoveries.

We are part of a network of European institutions whose goal is to foster the development and exploitation of Advanced Multi-Variate Analysis (AMVA) for New Physics searches. The network offers extensive training in both physics and advanced analysis techniques to graduate students, focusing on providing them with the know-how and the experience to boost their career prospects in and outside academia. The network develops ties with non-academic partners for the creation of interdisciplinary software tools, allowing a successful knowledge transfer in both directions. The network studies innovative techniques and identifies their suitability to problems encountered in searches for new physics at the LHC and detailed studies of the Higgs boson sector.

External collaborators: University of Oxford, INFN, University of Padova, Université Blaise Pascal, LIP, IASA, CERN, UCI, EPFL, B12 Consulting, SDG Consulting, Yandex, MathWorks.

Angular asymmetries in ttW production

We take advantage of the large statistics being recorded by the CMS experiment in Run 2 to launch a systematic study of angular asymmetries in the ttW process, which have a potentially large sensitivity to non-SM effects.
In synergy with the CP3 phenomenology group, we aim at reporting our results in a form that can be easily translated in EFT constraints.

Development of a framework for fast simulation of a generic collider experiment: Delphes

Observability of new phenomenological models in High Energy experiments is delicate to evaluate, due to the complexity of the related detectors, DAQ chain and software. Delphes is a new framework for fast simulation of a general purpose experiment. The simulation includes a tracking system, a magnetic field, calorimetry and a muon system, and possible very forward detectors arranged along the beamline. The framework is interfaced to standard file format from event generators and outputs observable analysis data objects. The simulation takes into account the detector resolutions, usual reconstruction algorithms for complex objects (FastJet) and a simplified trigger emulation. Detection of very forward scattered particles relies on the transport in beamlines with the Hector software.

Fast Simulation of the CMS experiment

A framework for Fast Simulation of particle interactions in the CMS detector (FastSim) has been developed and implemented in the overall simulation, reconstruction and analysis framework of CMS. It produces data samples in the same format as the one used by the Geant4-based (henceforth Full) Simulation and Reconstruction chain; the output of the Fast Simulation of CMS can therefore be used in the analysis in the same way as data and Full Simulation samples. FastSim is used in several physics analyses in CMS, in particular those requiring a generation of many samples to scan an extended parameter space of the physics model (e.g. SUSY) or for the purpose of estimating systematic uncertainties. It is also used by several groups to design future sub-detectors for the Phase-II CMS upgrades.
Related activities at UCL include the integration with the Full Simulation in the simulation of the electronic read-out ("digitization") and of the pileup of events from other proton-proton collisions, both in-time and out-of-time; the performance monitoring; and the overall maintenance and upgrade of the tracking-related code. Matthias Komm is current L3 convener of Tracking in FastSim, and Andrea Giammanco has been main responsible of the FastSim project from 2011 to 2013.

Imaging with cosmic-ray muons

The general goal of this project is to develop muon-based radiography or tomography (“muography”), an innovative multidisciplinary approach to study large-scale natural or man-made structures, establishing a strong synergy between particle physics and other disciplines, such as geology and archaeology.
Muography is an imaging technique that relies on the measurement of the absorption of muons produced by the interactions of cosmic rays with the atmosphere.
Applications span from geophysics (the study of the interior of mountains and the remote quasi-online monitoring of active volcanoes) to archaeology and mining.

We are part of the EU-funded H2020 network INTENSE where we coordinate the Muography work package, which brings together particle physicists, geophysicists, archaeologists, civil engineers and private companies for the development and exploitation of this imaging method.

We are using the local facilities at CP3 for the development of high-resolution portable detectors.
We also participate to the MURAVES collaboration, now merged into the MIVAS collaboration, through algorithmic and data-analysis aspects like the implementation of time-of-flight capabilities, the analysis of control data for the optimization of the reconstruction algorithms, and the understanding of physics and instrumental backgrounds by data-driven and simulation techniques.

External collaborators: UGent; INTENSE Research & Innovation Staff Exchange network (Japan, Switzerland, Italy, France, Hungary); MIVAS Collaboration (France and Italy) including CNRS (France), INFN (Italy), INGV(Italy).

Luminosity calibration of the CMS detector

We contribute to the offline absolute calibration of the luminometry system of the CMS detector, by analysing the dedicated "Van der Meer scan" data at different center-of-mass energies and collision types (p-p, p-Pb, Pb-Pb).

As a related task, we also contribute to the data-driven inference of the true amount of "pile-up" collisions.

External collaborators: CMS Luminosity Physics Object Group.

Search for exotic decays of the Higgs boson to a pair of new light bosons with two muons and two b jets in final states

We search for exotic decays of a Higgs boson to a pair of new light bosons, H->a1a1, where one of the light bosons decays to a pair of muons and the other one decays to a pair of b quarks. Such signatures are predicted in a number of well motivated extensions of the standard model, including the next-to-minimal supersymmetry and generic two Higgs doublet models with an additional scalar singlet.

Single top studies at LHC

The electroweak production cross section of single top quarks is an important measurement for LHC, being a potential window on "new physics" effects.
Past achievements of this group include the very first measurement at 7 TeV (in t channel) with 2010 data, followed by the most precise inclusive cross section measurements of t-channel cross section at 7, 8 and 13 TeV, and the first differential measurements at 13 TeV; the most precise |Vtb| extraction from single top in the world; the first measurement of W-helicity fractions in a single-top topology; the first observation of the tW production mode; the first measurement of single-top polarization in t channel; stringent limits on anomalous tWb, tgu, tgc couplings.

External collaborators: CMS collaboration.

Testing the sign of the coupling of the new H(125) boson to top quarks with the CMS data

During 2012, the CMS and ATLAS collaborations independently reported unambiguous evidence of the existence of a new particle of mass around 125 GeV.
Several analyses are ongoing to challenge the hypothesis that the new particle is the SM Higgs. We focus on the search for its production in association with a single top quark. Due to an effect of quantum interference, this process is strongly suppressed in the Standard Model while it gets enhanced if its couplings to the top quark and to the W boson have opposite sign. An observation of this production mode would therefore be a convincing proof that this new particle does not belong to the Standard Model.
We published the first search for this process using 8 TeV data, and we expect to achieve sensitivity to anomalous values of the top Yukawa phase during the LHC Run-II.

External collaborators: CMS collaboration.

Top quarks in Heavy Ion collisions and other non-standard LHC datasets

The top quark, being the heaviest known elementary particle, is a powerful tool to test QCD.
The study of top quark pair production in Heavy Ion collisions at the LHC, making use of the dedicated Pb-Pb and p-Pb runs, will open a new road in the investigation of the Quark-Gluon Plasma.

This research project started with the first measurement of top-pair cross section in pp collisions at 5.02 TeV, taking advantage of a "reference run" in Nov.2015. This measurement, in addition to being useful as a reference for measurements in Pb-Pb and p-Pb collisions at the same center-of-mass energy per nucleon, also provides a significant broadening of the lever arm for global PDF fits making use of top-quark data.

More recently we reported the first observation of top quark production in p-Pb collisions, using the data at 8.16 TeV taken in Nov.2016, testing the models of nuclear modification of the gluon PDF at high Bjorken-x.

We are now preparing future analyses in PbPb collisions. We are also interested in differential analyses in pPb collisions (to constrain nuclear PDFs) and in searches in central exclusive production pp events.

External collaborators: David D'Enterria, Pedro Silva and Marta Verweij (CERN).


Show past projects.
Publications in CP3
Showing 5 publications over 86. Show all publications.
All my publications on Inspire

2018

Model-independent constraints on the CKM matrix elements $|V_{tb}|$, $|V_{ts}|$ and $|V_{td}|$
Clerbaux, Barbara and Fang, Wenxing and Giammanco, Andrea and Goldouzian, Reza
[Abstract] [PDF] Submitted to JHEP.
Refereed paper. 9th August.
Search for the associated production of a Higgs boson and a single top quark in pp collisions at sqrt(s)=13 TeV
CMS Collaboration
[Full text] Physics Analysis Summary HIG-18-009, Presented at the XXXIX International Conference on High Energy Physics, ICHEP 2018, Seoul, South Korea, 4-11 July, 2018
Public experimental note. 6th July.
A portable muon telescope based on small and gas-tight Resistive Plate Chambers
Wuyckens, Sophie and Giammanco, Andrea and Demin, Pavel and Cortina Gil, Eduardo
[Abstract] [PDF] Proceedings of the "Cosmic-Ray Muography" meeting of the Royal Society, 14-15 May 2018 at the Kavli Royal Society Centre, Chicheley Hall, Newport Pagnell (UK). Submitted to Philosophical Transactions of the Royal Society A.
Contribution to proceedings. 18th June.

2017

The Phase-2 Upgrade of the CMS Tracker
CMS collaboration
[Full text] CERN-LHCC-2017-009 ; CMS-TDR-014
Refereed paper. 13th December.
TOP2017: Experimental Summary
Giammanco, Andrea
[Abstract] [PDF] Proceedings of the TOP2017 conference.
Contribution to proceedings. 6th December.


[UCLouvain] - [SST] [IRMP] - [SC]
Contact : Jérôme de Favereau
Research
Job opportunities Postdoctoral Position on advanced analysis techniques applied to the CMS di-Higgs study
Post-doctoral positions in collider phenomenology and particle astrophysics
Postodoctoral position in SoLid
EOS be.h : 10 PhD positions