1/22DNEG meeting, March'19 David d'Enterria (CERN)

Intro to experimental high-energy particle physics (Future Circular Collider)

FCCPS

SPS

LHC

David d'Enterria (CERN)

2/22DNEG meeting, March'19 David d'Enterria (CERN)

Elementary particles & interactionsElementary particles & interactions☞There are 17 known elementary particles that interact via 3 forces:

nuclear strong, nuclear weak, electromagnetism (+gravity)

3/22DNEG meeting, March'19 David d'Enterria (CERN)

Elementary particles & interactionsElementary particles & interactions ☞ Visible universe made of the 8 lightest ones: u,d,g (p,n), electrons, light, neutrinos

☞ The rest (9) are heavier, virtual, unstable: Production in accelerators/colliders,

reconstructed in detectors directly or (if too short-lived) from decay particles.

4/22DNEG meeting, March'19 David d'Enterria (CERN)

Particle colliders in a nutshell (LHC)Particle colliders in a nutshell (LHC)p accelerated & stored & collided in ring:

p-p collisions recorded in detectors:

5/22DNEG meeting, March'19 David d'Enterria (CERN)

The Large Hadron Collider (LHC) ringThe Large Hadron Collider (LHC) ring

CMS / TOTEM

ATLAS / LHCf

ALICE

LHCb / Moedal

~26.7 km circunference. ~80 m underground.

Superconducting magnets (1.9K): 1230 dipoles + 400 focusing

4 machine points: RF accelerator, collimators/clean., beam-dump

4 interaction points instrumented: 7 experiments

Sections: 8 “insertions” (straight) + 8 “arcs” (dipoles)

6/22DNEG meeting, March'19 David d'Enterria (CERN)

The LHC operation & experimentsThe LHC operation & experiments

TOTEM

LHCb

ALICE ATLAS

CMS

LHCf

~8.5 km

Lac Léman

Jura

Moedal

p-p collisions at p-p collisions at √√s = 14 TeV, s = 14 TeV, ℒℒ=10=103434 cm cm-2-2ss-1-1, 8 mo/yr, 8 mo/yr

Pb-Pb collisions at Pb-Pb collisions at √√s = 5.5 TeV, s = 5.5 TeV, ℒℒ=10=102727 cm cm-2-2ss-1-1, 1 mo/yr, 1 mo/yr

7/22DNEG meeting, March'19 David d'Enterria (CERN)

The LHC experimentsThe LHC experiments

Services routing:

From Castor to Racks

Patch Panels

T2 Services routing:

From Castor to Racks

Patch Panels

T2

TOTEM LHCf Moedal

8/22DNEG meeting, March'19 David d'Enterria (CERN)

Main LHC experiments: ATLAS & CMSMain LHC experiments: ATLAS & CMS

Underground cavern

9/22DNEG meeting, March'19 David d'Enterria (CERN)

Generic particle detectorGeneric particle detector ☞ Detectors take snapshots of the particles' “debris” of each collision:

Jets of hadrons (=quarks & gluons), if extra secondary vertex (heavy-quarks)

electrons/photons, muons, missing energy (=neutrinos):

10/22DNEG meeting, March'19 David d'Enterria (CERN)

Particle detection (ATLAS)Particle detection (ATLAS) ☞ Detectors take snapshots of the particles' “debris” of each collision:

Jets of hadrons (=quarks & gluons), if extra secondary vertex (heavy-quarks)

electrons/photons, muons, missing energy (=neutrinos):

11/22DNEG meeting, March'19 David d'Enterria (CERN)

Particle detection (CMS)Particle detection (CMS) ☞ Detectors take snapshots of the particles' “debris” of each collision:

Jets of hadrons (=quarks & gluons), if extra secondary vertex (heavy-quarks)

electrons/photons, muons, missing energy (=neutrinos):

12/22DNEG meeting, March'19 David d'Enterria (CERN)

Charged particle detection (tracker)Charged particle detection (tracker) ☞ Jets of charged hadrons (p,n,, k,…) from light-quarks, gluons, heavy-quarks,

as well as electrons and muons: Generate signals traversing sensitive layers,

that are reconstructed assuming bent trajectories in the magnetic field.

13/22DNEG meeting, March'19 David d'Enterria (CERN)

Muon detection (tracker+spectrometer)Muon detection (tracker+spectrometer) ☞ Muons interact weakly with the detector material: they traverse the whole

apparatus, generating signals in the inner- & outer-most tracker layers.

Reconstructed by fitting their bent trajectories in the magnetic field(s).

14/22DNEG meeting, March'19 David d'Enterria (CERN)

Electron/photon energy detection (ECAL)Electron/photon energy detection (ECAL) ☞ Photons and electrons, produced directly or in the decay of hadrons from

light & heavy quarks & gluons, generate showers in calorimeters:

15/22DNEG meeting, March'19 David d'Enterria (CERN)

Neutrino & new weakly-interacting particlesNeutrino & new weakly-interacting particles

☞ Neutrinos as well as any new weakly-interacting particles (e.g. dark-matter)

traverse the full detector without interacting: Seen as “missing energy”

16/22DNEG meeting, March'19 David d'Enterria (CERN)

Example: Z boson reconstructionExample: Z boson reconstruction ☞ After being produced, the Z boson lives for t 10-24 s, and decays

into different pairs of stable particles, e.g. Z→muon+muon:

(More event displays

in Jeremi's talk next)

17/22DNEG meeting, March'19 David d'Enterria (CERN)

Example: Higgs boson reconstructionExample: Higgs boson reconstruction ☞ After being produced, the Higgs boson lives for t 5·10-14 s, and decays into

different pairs of particles, e.g. H→photon+photon, or H→Z+Z*→4 muons

(More event displays

in Jeremi's talk next)

18/22DNEG meeting, March'19 David d'Enterria (CERN)

Future Circular ColliderFuture Circular Collider

19/22DNEG meeting, March'19 David d'Enterria (CERN)

The FCC ringThe FCC ring

• ~100 km tunnel infrastructure in

Geneva area

• e+e- collider (FCC-ee)

as a first step (15 years op.)

• pp-collider (FCC-hh) long-term goal (25 years op.) defining infrastructure requirements

Magnetic dipoles of ~16 T 100 TeV pp in 100 km

HE-LHC

31 GHz of pp collisionsPile-up 1.0004 THz of tracks

20/22DNEG meeting, March'19 David d'Enterria (CERN)

FCC-hh reference detector cavernFCC-hh reference detector cavern

Distance of 50m for• civil engineering• Stray magnetic field reduction• Radiation shielding (10-15m would

be sufficient)Service Cavern

Detector Cavern

21/22DNEG meeting, March'19 David d'Enterria (CERN)

FCC-hh reference detectorFCC-hh reference detector• 4 T, 10-m solenoid, unshielded• Forward solenoids, unshielded• Silicon tracker• Barrel ECAL LAr• Barrel HCAL Fe/Sci• Endcap HCAL/ECAL LAr• Forward HCAL/ECAL LAr

50m length, 20m diameterSimilar in size to ATLAS

22/22DNEG meeting, March'19 David d'Enterria (CERN)

FCC detector compared to ATLAS & CMSFCC detector compared to ATLAS & CMS

(FCC-hh detector)(ATLAS & CMS detectors)

23/22DNEG meeting, March'19 David d'Enterria (CERN)

Backup slidesBackup slides