CLIC Detector and Physics Collaboration Meeting

29 Aug 2017, 08:00 → 30 Aug 2017, 18:00 Europe/Zurich

503/1-001 - Council Chamber (CERN)

The 2-day meeting on the CLIC detector and physics study will start on Tuesday 29 August 08:30 and will end on Wednesday 30 August around 17:30. Most of the time will be devoted to topical sessions, providing an overview of ongoing activities and future plans. In order to allow the participants to get a good overview of the work in CLICdp, we try to avoid parallel sessions. The timetable presently proposed is tentative - sessions can be shortened/extended at a later stage, according to the proposed number of talks.

We foresee to have the following topical sessions (and conveners):

• Physics and Analysis (Esteban Fullana, Juergen Reuter, Rickard Strom)
• Software / Detector Validation (Matthias Weber, Andre Sailer)
• Vertex / Tracker R&D (Mathieu Benoit, Andreas Nurnberg, Simon Spannagel)
• FCAL / ECAL / HCAL R&D (Aharon Levy, Frank Simon)

A CLICdp Institute Board meeting is scheduled for Tuesday lunchtime, 29 August.

The workshop dinner is scheduled for Tuesday evening, 29 August, 19h30 at La Maison d'Asie in Geneva (cost: 50 CHF all included).

Tuesday, 29 August

08:00 → 08:30 Registration

08:30 → 10:00 CLICdp Plenary: Welcome

08:30 Welcome and General News

Speaker: Lucie Linssen (CERN)

Linssen_CLICdp_News-August2017.pdf

Linssen_CLICdp_News-August2017.pptx

08:50 Report from the CLIC Communication Initiative (CCI)

Speaker: Lars Rickard Strom (CERN)

CCI_CLICdp_coll_meeting_2017_stroem.pdf

09:05 Update on CLIC BDS tuning and luminosity performance

Speaker: Fabien Plassard (Universite de Paris-Sud 11 (FR))

clicdp-WS_BDS-optim-update.pdf

09:20 Beam-induced backgrounds at 380 GeV CLIC

Speaker: Dominik Arominski (Warsaw University of Technology (PL))

Beam-induced backgrounds at CLIC.pdf

09:35 Cooling of ECAL and HCAL

Speaker: Katja Krueger (Deutsches Elektronen-Synchrotron (DE))

Cooling_CLICdp_20170829.pdf

10:00 → 10:30 Coffee Break

10:00 → 10:30 Registration

10:30 → 12:00 Physics/Analysis

Conveners: Esteban Fullana Torregrosa (Univ. of Valencia and CSIC (ES)), Jürgen Reuter (DESY Hamburg, Germany), Lars Rickard Strom (CERN)

10:30 Limits on top FCNC decay t->cH from CLIC at 380 GeV

Prospects for measuring top FCNC decays at 380 GeV were studied with the full simulation samples including signal sample generated with the WHIZARD implementation of the 2HDM(III) model and the standard six-fermion event samples used for top pair production studies. Analysis was divided into three steps: event classification, kinematic reconstruction based on signal or background hypothesis and final signal vs background discrimination. To obtain optimal results, selection criteria based on the dedicated Boosted Decision Tree (BDT) responce were used at each step. Expected limits on BR(t->cH)*BR(H->bb) are presented.

15 minutes presentation + 5 minutes discussion

Speaker: Aleksander Filip Zarnecki (University of Warsaw)

zarnecki_clicdp2017.pdf

10:50 Update on FCNC t->c gamma at 380 GeV

In the Standard Model, FCNC top decays, are very strongly suppressed. Observing such a decay would be a direct signature of physics beyond the SM as large enhancements are possible in many "new physics" scenarios. A full simulation study for CLIC at 380 GeV based on a WHIZARD simulation of FCNC top decay t -> c gamma within the 2HDM(III) model is performed. An update on this analysis including background suppression of standard top decay channels (cut based and TMVA) is presented, including a first estimate of the discovery limit.

15 minutes presentation + 5 minutes discussion

Speaker: Naomi Van Der Kolk (Max-Planck-Institut fur Physik (DE))

FCNC_20170829.pdf

11:10 Status of ee -> gamma gamma analysis

The CLIC sensitivity to the QED process ee->gamma gamma
at 3 TeV is studied using SiD geometry model.
The estimated precision on total and differential
cross-sections is converted into the exclusion limits
on various New Physics models, including finite electron size,
extra dimensions, contact interactions, excited electrons.

Speaker: Igor Boyko (Joint Institute for Nuclear Research (RU))

boyko_eegg_20170829.pdf

11:25 BSM Hidden valley searches

Sensitivity studies of the BSM Hidden Valley particles have been performed for the e+e- collisions at the centre-of-mass energy of 3 TeV in the CLIC detector,
corresponding to an integrated luminosity of 2 ab-1. Hidden Valley particles may be stable, providing dark matter candidates and missing energy signals,
but others may decay into neutral combinations of Standard Model particles. Since the Higgs boson may also decay into two Hidden Valley particles, providing
four b-jets in the final state which are away from the primary vertex and the beam axis, analysis relies on loosely reconstructed displaced vertices assigned to the b-jets.
The final aim of the present analysis is to determine the upper limits of the cross sections for the Hidden Valley particle production for different masses and lifetimes.

Speaker: Marcin Kucharczyk (Polish Academy of Sciences (PL))

HiddenValley_MKucharczyk_2017.08.29.pdf

11:45 The Higgs couplings and self-coupling in the EFT framework

We study the reach on the Higgs coupling constraints at future lepton colliders in a global effective-field-theory framework. The impact and complementarity of different measurements, at different center-of-mass energies and for several beam polarization configurations, are discussed in detail. This framework is also applied to study the constraints on the Higgs self-coupling. Based on arXiv:1704.02333 and current study.

12 minutes presentation + 3 minutes discussion

Speaker: Jiayin Gu (DESY)

eex6.pdf

12:00 → 14:00 Lunch

12:15 → 13:45 CLICdp Institute Board

https://indico.cern.ch/event/656038/

CLICdp Institute Board

14:00 → 16:00 FCAL/ECAL/HCAL R&D

Conveners: Aharon Levy (Tel Aviv University (IL)), Frank Simon (Max-Planck-Institut fuer Physik)

14:00 FoCal: MAPS digital calorimetry

Speaker: Naomi Van Der Kolk (Max-Planck-Institut fur Physik (DE))

FoCal_20170829.pdf

14:23 The CALICE AHCAL: Progress with the Technical Prototype

Speaker: Felix Sefkow (Deutsches Elektronen-Synchrotron (DE))

HCAL-CLIC-Aug17.pdf

wrapping_58sek_manual.mp4

14:46 The CMS HGCAL Testbeams

Speaker: Thorben Quast (Rheinisch-Westfaelische Tech. Hoch. (DE))

HGCALTestbeams_Quast_08_29.pdf

15:09 Beam test of a compact LumiCal prototype

Speaker: Maryna Borysova (National Academy of Sciences of Ukraine (UA))

CLICDP_mb.pdf

15:26 LumiCal performance in combination with a tracking detector

Speaker: Oleksandr Borysov (Tel Aviv University (IL))

lumical_tracking_clicdp2017.pdf

15:43 New developments of the BeamCal

Speaker: Oleksandr Borysov (Tel Aviv University (IL))

beamcal_clicdp2017.pdf

16:00 → 16:30 Workshop Photo and Coffee break

16:30 → 18:30 Physics/Analysis

Conveners: Esteban Fullana Torregrosa (Univ. of Valencia and CSIC (ES)), Jürgen Reuter (DESY Hamburg, Germany), Lars Rickard Strom (CERN)

16:30 Top Yukawa coupling measurement at 1.4 TeV at CLIC

The precision on the top Yuakwa coupling is measured in the e+e -->t ̄tH process at sqrt(s) = 1.4 TeV using Compact Linear Collider (CLIC). The analysis focuses on the 6 jets and 8 jets final states channels using particle flow technique. Leptons are identified first follow by clustering the remaining particles into jets and removing the beam jets. Particles that are not identified as leptons are reclustered into jets and performed flavour-tagging. Optimal selection are investigated to select leptons and to suppress the beam-induced backgrounds. Collection of variables are used as input to the BDT to select signals. The precision of the top Yukawa coupling in the semi-leptonic channel is determined to be 5.92% with no beam polarisation.

12 minutes presentation + 3 minutes discussion

Speaker: Mr Yixuan Zhang (University of Edinburgh (GB))

clic_ppt.pdf

16:45 WW/ZZ separation and timing cut comparison for old and new CLIC detector model

15 minutes presentation + 5 minutes discussion

Speakers: Sascha Simon Dreyer, Lars Rickard Strom (CERN), Matthias Artur Weber (CERN)

sdreyer_wwzz.pdf

17:05 Top forward-backward asymmetry with boosted reconstruction methods at multi-TeV CLIC

In this contribution we outline the path towards studying top quark properties at the multi-TeV collisions of the CLIC physics programme. We discuss the jet reconstruction performance utilising a fat-jet approach and subsequent methods to identify the underlying top sub-structure in boosted topologies. We present results on the cross-section and forward-backward asymmetry as well as an interpretation of the results from the full CLIC programme in terms of EFT operators.

15 minutes presentation + 5 minutes discussion

Speaker: Lars Rickard Strom (CERN)

boosted_top_clicdp_coll_meeting_2017_stroem.pdf

17:25 The top-antitop threshold in WHIZARD

In this talk I will report on recent progress in the implementation of threshold resummation into the Monte Carlo event generator WHIZARD. This is crucial for reliable predictions of WWbb production close to the top-antitop threshold. As a key feature we establish a smooth transition between the threshold region and the relativistic (NLO) continuum. For the first time our code allows to study arbitrary differential observables involving the decay products of the tops and including interference with non-resonant background processes at threshold and beyond.

15 minutes presentation + 5 minutes discussion

Speaker: Maximilian Stahlhofen

CLICdp_29Aug2017_v3.pdf

17:45 A Top Threshold Scan with with Luminosity Spectrum of the 380 GeV Machine

I will present an update of the study of the top mass measurement and other top properties in a threshold scan, now using the luminosity spectrum of the new CLIC baseline machine. The optimisation of the machine for 380 GeV instead of 500 GeV leads to increased beamstrahlung when operated in the top threshold region, which may result in a degradation of the sensitivity of a threshold scan. The impact of this change will be discussed in the presentation.

12 minutes presentation + 3 minutes discussion

Speaker: Frank Simon (Max-Planck-Institut fuer Physik)

TopThresholdNewSpectrum.pdf

19:30 → 21:30 Workshop dinner at "La Maison d"Asie": Workshop dinner

19:30 Workshop Dinner: how to get to the restaurant - by tram

workshop dinner.pdf

workshop dinner.pptx

Wednesday, 30 August

08:30 → 10:00 Vertex / Tracker R&D

08:30 The Allpix2 Simulation Framework

Speaker: Koen Wolters (Eindhoven Technical University (NL))

linear_propagation.gif

tcad_propagation.gif

Wolters_Allpix_30_08_2017.pdf

Wolters_Allpix_30_08_2017.ppt

08:50 SOI test beam and irradiation studies

Speakers: Roma Bugiel (AGH University of Science and Technology (PL)), Szymon Bugiel (AGH University of Science and Technology (PL))

2017_CLIC_CollaborationMeeting.pdf

09:10 Analysis & Simulations of the Investigator Chip

Speaker: Ruth Magdalena Munker (University of Bonn (DE))

clicws_08_2017_munker.pdf

09:30 Simulations and Glue Studies for Capacitively Coupled Sensors

Speaker: Mateus Vicente Barreto Pinto (Universite de Geneve (CH))

ccpd_mvicente.pdf

10:00 → 10:30 Coffee Break

10:30 → 11:30 Software / Detector Validation

Conveners: Andre Sailer (CERN), Matthias Artur Weber (CERN)

10:30 iLCDirac Status

Speaker: Marko Petric (CERN)

iLCDirac_Status_petric.pdf

11:00 Software Status

Speaker: Andre Sailer (CERN)

170830_sailer_softcomp.pdf

11:30 → 13:00 Vertex / Tracker R&D

Conveners: Andreas Nürnberg (CERN), Mathieu Benoit (UNIGE), Simon Spannagel (CERN)

11:30 Analysis & Simulations of CLICpix+CCPDv3 Assemblies

Speaker: Matthew Daniel Buckland (University of Liverpool (GB))

MBuckland_30-08-2017.pdf

11:50 Characterization of Capacitively Coupled HR/HV-CMOS Sensor Chips

Speaker: Iraklis Kremastiotis (KIT - Karlsruhe Institute of Technology (DE))

C3PD_Measurements_20170830.pdf

12:10 Status of the CaRIBOu DAQ System

Speaker: Adrian Fiergolski (CERN)

A.Fiergolski_CaRIBOu.pdf

12:30 Lab & Test Beam Charactierization of the CLICpix2 Chip

Speakers: Andreas Nürnberg (CERN), Simon Spannagel (CERN)

20170830_clicdp_meeting.pdf

13:00 → 14:00 Lunch

14:00 → 15:30 Software / Detector Validation

14:00 Tracking Validation

Speakers: Daniel Hynds (CERN), Emilia Leogrande (CERN)

CLIC_CollaborationMeeting_30Aug2017.pdf

14:25 Impact Parameter Resolution

Speaker: Peter Winkel Rasmussen (Summer Student)

Presentation.pdf

14:40 Flavour Tagging

Speaker: Mr Ignacio Garcia Garcia (Univ. of Valencia and CSIC (ES))

Nacho_clicdp_collaboration_meeting_17.pdf

15:05 Calorimeters and Pandora Performance

Speaker: Matthias Artur Weber (CERN)

170830_Weber_CLIC_PFlow_Validation.pdf

15:30 → 16:00 Coffee Break

16:00 → 17:35 CLICdp Plenary

16:00 Report from the CLIC physics potential WG

Speaker: Jorge de Blas (Universita e INFN, Padova (IT))

Phys_Pot_WG_Report.pdf

16:25 Analysis overview

Speaker: Philipp Roloff (CERN)

clicdp_collaboration_meeting_august_2017_roloff.pdf

16:45 Report from the Speakers Committee

Speaker: Igor Boyko (Joint Institute for Nuclear Research (RU))

SC_2017aug.pdf

17:00 Report from the Publication Committee

Speakers: Aleksander Filip Zarnecki (University of Warsaw), TBC

clicdp2017_pubcom.pdf

17:15 Report from the Institute Board meeting

Speakers: Aidan Robson (University of Glasgow (GB)), Victoria Jane Martin (University of Edinburgh (GB))

clicdp_IBreport170830.pdf