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Home , Dark matter, Large Hadron Collider

Future Prospects for

Albert De Roeck CERN, , Antwerp University Belgium UC-Davis California USA BU, Cairo, Egypt NTU, Singapore

Santiago de la Compostela 3rd September 2019 Experiments: CMS (CERN), MoEDAL (CERN), DUNE (FNAL), T2K (Japan), (Belgium)… + a few other (smaller) experiments + studies for the future.. Outline

• Introduction: Experimental Techniques • Results from the Large -The Higgs -? Dark ?..? • The Future at the LHC Collider/accelerator based view • Next possible Facilities/Challenges • Summary 2 What is the world made of? What holds the world together? Where did we come from? High Physics Experiments

First High Energy Physics High Energy Physics Experiments: Experiments since mid 70’s: Beam on fixed target! Colliding beams!

Rutherford experiment (1913)

Centre of energy squared s=2E1m2 Centre of mass energy squared s=4E1E2 …plus secondary beams such as … The Rutherford Experiment

1913

Rutherford experiment: Unexpected Backscattering of α-: Evidence for the structure of !! H. Geiger (postdoc) and E. Marsden (undergraduate) were the “electronics” of the detector

But modern experiments without electronics are (almost) unthinkable!!! Accelerators are Powerful Microscopes

Planck constant High energy particle beams h allow us to see small things  = p wavelength ~ energy

High energy particle beams allow us to produce massive particles The

gauge

x8

In 50 years, we’ve come a long way, but there is still much to learn…

Fermions: particles with spin ½ : particles with integer spin

Until 2011 no single fundamental scalar had been observed yet! Do they exist in ? Physics case for new High Energy Machines From ~1990’s Understand the mechanism Electroweak Breaking Discover physics beyond the Standard Model Reminder: The Standard Model - tells us how but not why 3 flavour families? Mass spectra? Hierarchy? 19 parameters! - needs fine tuning of parameters to level of 10-30 ! - has no connection with - no unification of the forces at high energy

Most popular extensions around 2000 - Supersymmetry - Extra space Many other ideas: More symmetry and gauge bosons, , L-R symmetry, & substructure, models, , Hidden Valleys, Vector-like …

Higgsless models rather disfavoured these days The Hunt for the Higgs The key question (pre-2012): Where do the of Does the Higgs particle exist? elementary particles come from? If so, where is the Higgs? Massless particles move at the speed We do not know the of light -> no formation!! mass of the

Scalar field with at least Note: NOT the mass of It could be anywhere and one scalar particle from 114 to ~7009 GeV The LHC Machine and Experiments

moedal LHCf

totem

 Seven LHC experiments in operation! ..Proposals for additional “small” experiments to cover more… The Large = a proton collider

Also a heavy collider 7 TeV + 7 TeV 6.5 TeV + 6.5 TeV (4/3.5 TeV + 4/3.5 TeV)

Primary physics targets  Origin of mass  Nature of  Understanding space time  Matter versus  Primordial

The LHC is a Discovery Machine The LHC can determine the future course of High Energy Physics Reminder: This is what we do!

proton proton 13 TeV

…40 Million times a second - 24/7 (if we could)

Out comes the Higgs & New Physics (…or not)

The Compact Solenoid Experiment The CMS Collaboration: >3200 scientists and engineers, >800 students from ~190 Institutions in 44 countries .

In total about ~100 000 000 electronic channels Each channel checked 40 000 000 times per second (bunch X rate is 40 MHz) An on-line trigger selects events and reduces the rate from 40MHz to ~ 1kHz Amount of data for just one bunch crossing ~2 000 000 Bytes CMS before closure

Can be seen as above during the CERN open door days: 14-15 September… From Collisions to Papers…

Pile-up: multiple collisions in one bunch crossing ~ 40!

Readout Electronics..

Event Builder and Trigger Electronics 2012: A Milestone in

Observation of a Higgs Particle at the LHC, after about 40 years of experimental searches to find it

proton proton

2013

The Higgs particle was the last missing particle in the Standard Model and possibly our portal to physics Beyond the Standard Model Most cited LHC paper so far... September 2012 Special Physics Letters B edition CMS week Lisboa with the ATLAS and CMS CMS papers on the Higgs Discovery Also…

Elsevier

PHYSICS LETTERS B

Cited about 9500 times so far… Tuesday 8 October 2013

Francois Englert Congratulations!!!!

19 Brief Higgs Summary (so far)

We know already a lot on this brand New Higgs particle!!

Mass = CMS+ATLAS Width Couplings are Spin = 125.09 ±0.21(stat) < 9 MeV within ~10-20% 0+(+) preferred ±0.11(syst) GeV (95%CL) of the SM values over 0-,1,2

We continue to look for anomalies, i.e. unexpected decay modes or couplings, multi-Higgs production, heavier Higgses, charged Higgses… Brief Higgs Summary (so far)

Combination of all Higgs production/decay channels at 13 TeV Check overall consistency of the couplings

ATLAS-CONF-2018-031 CMS: arXiv:1809.10733 Results in agreement with the Standard Model The Study of the Higgs

June 2019 FCC meeting The Future: Studying the Higgs…

More LHC Data 2021-2023 LHC upgrade ! 2026-2036 Experiment upgrades!! Other/new machines? -> see later

Many questions are still unanswered: What explain a Higgs mass ~ 125 GeV? What explains the particle mass pattern? Connection with Dark Matter? What is the origin of masses? … Physics Beyond the Standard Model?

A Higgs at 125 GeV Precise measurements of the and the Higgs mass

arXiv:1403.6535 We also know that:

New Physics inevitable? But at which scale/energy?

Searches!!

N. Arkani-Hamed New Physics? J. Ellis, 2017 007 Reasons for new Physics https://ep-news.web.cern.ch • 001) Within the Standard Model, the electroweak vacuum is unstable against decay to high Higgs field values. • 002) The Standard Model has no candidate for dark matter. • 003) The Cabibbo-Kobayashi-Maskawa (CKM) Model does not explain the origin of the matter in the . Where is the anti-matter? • 004) The Standard Model does not have a satisfactory mechanism for generating neutrino masses. • 005) The Standard Model does not explain or stabilize the hierarchy of mass scales in physics. • 006) The Standard Model does not have a satisfactory mechanism for cosmological . • 007) We need a quantum theory of gravity. Beyond the Higgs Boson Supersymmetry: a new symmetry in Nature?

Candidate particles for Dark Matter  Produce Dark Matter in the lab

SUSY particle production at the LHC Picture from Marusa Bradac The SUSY SEARCH Chart So Far…

No evidence for SUSY found yet. More than 100 different analyses performed Excluded squark and mass region:

Excluded!!

EPS19/LP19: Still no significant sign yet of SUSY with full run-2 data (140fb-1) SUSY (as seen from outside HEP…) But we are not November ‘16 reported by The Economist (!?!): giving up yet!!!

A lot more analyses are still ongoing. New ideas being tried out

Keep the party ready..

http://www.economist.com/news/science-and-technology/21709946-supersymmetry-beautiful-idea-there-still-no-evidence-support-it Dark Matter Searches at the LHC

Identifying Dark Mono- object Matter is one of the signature most important questions in physics Is Dark Matter today! a new weakly It is likely a new as yet interacting undetected particle particle??? Can it be produced at the LHC? Comparison with Direct Detection

No signal seen in any of the “mono”-signals so far Extend limits by search for the mediator

Axial-vector mediator and Vector mediator and Spin-dependent direct limits Spin-independent direct limits

90% CL limits Mono-jet/V & Dijet searches are typically the most sensitive ones New Physics Searches: Limits!!

31 Are we leaving no stone unturned?

• The LHC BSM searches are indispensable and should be continued in the new energy regime and with increasing statistics (higher mass, lower couplings) • But if we still do not see more than a 2 sigma at the end of run-3, the HL-LHC will be likely mostly a precision physics machine, searching for subtle deviations • Are we looking at the right place? Time for more effort in thinking of complementary searches? Are we looking at the right place? Leave no stone unturned!! LHCb: Tests of Lepton Universality A few puzzling results from the LHCb experiment…

If confirmed, independent checks will become very important. Belle II? ->in a few years form now

CMS has installed a special trigger to collect an unbiased b-sample which is active since 2018 -> more than 1010 b-pairs collected during 2018 via parked data stream

First LHCb run-2 results did not yet clarify the situation (Moriond 2019) MoEDAL: Monopole and Exotics Detector at the LHC

Heavy particles which carry “magnetic charge” Could eg explain charge quantization in the Universe

Monopole production

Remove the sheets after some running time and inspect for ‘holes’ Monopole Searches: MoEDAL @ 13TeV 2016 data analysis base on 794 kg Aluminium to “stop” the monopoles and search for them with a SQUID precision (4.0fb-1) arXiv:1903.08491

Limits for different monopole charges First monopole search result @LHC at 13 TeV No signal yet. Proposals for New Experiments @LHC

MilliQan: searches for CODEX-b: searches for long lived millicharged particles weakly interacting neutral particles

MATHUSLA: searches for long lived FASER: searches for long lived weakly interacting neutral particles dark -like particles

Recent also AL3X (re-use of ALICE for LLP)… The New Wave:

M. Pierini et al. The New Wave: Machine Learning

Field Programable Gate Array LHC: The Next Step

High Luminosity LHC pile-up -> ~ 200 events per bunch crossing

All LHC experiments plan upgrades for either 2019-2020 or 2024-2026 for the High Luminosity LHC upgrade (ATLAS, CMS and LHCb, ALICE)

Approved LHC program to collect 3000 fb-1 in total with the LHC (HL-LHC) Maximize the reach for searches and for precision measurements (eg Higgs)

LHC will run till ~2037 Then a high energy LHC (28 TeV)?? This option is discussed @ CERN.. The European Strategy for Particle Physics update 2016 Similar machine(s) proposed in China! -> e+e-: CEPC; hh: SppC Linear Collider Projects

ILC Japan -Superconducting cavities -250 GeV CMS Energy -Extendable

Future uncertain!

Higgs Factories! CLIC Project CERN - Two beam accelerator scheme Bunch crossing every 0.5 ns - Staged construction. Up to 3 TeV CMS Energy Projects

MAP scheme

LEMA scheme

Lifetime at rest of a muon is 2.3 휇secs: Speed is of issue. Large backgrounds! High intensity: high data rates and volumes! More than 20 proposed projects

Also many interesting QCD related projects! Data: 30 Pbyte/year!! Approved a few weeks ago! Your Challenges Ahead!

•High Luminosity LHC: 300Tb/sec at the front end, 8 Mbyte event size •CLIC: bunch crossings every 0.5 nanoseconds •DUNE: 30 Pbyte/year storage, 2.5 msec drift times, electronics in the cold… •Future trigger-less data taking, even for hadron (!?!) •…

FCC-hh -> Maybe for 2060?

…and the high intensity frontier with GHz event rates… Summary

• Electronics are clearly an indispensable part of (almost all) particle physics experiments. Requirements get more demanding with time by demands by the experimentalists • Next generations of experiments at future colliders or at the high intensity frontier will push these to requirements even further. There are challenges ahead! • No sign of new physics in the 13 TeV data so far… But the LHC is not done yet! New small experiments being poposed • The community prepares a strategy for the future. A next large circular/linear collider? High intensity frontier experiments & intense neutrino beams, muon colliders, MEGII, g-2...??? • The LHC is continuing to explore the Terascale. It takes on significant deviation to show the way!!. …And hopefully one day soon now: 50