news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

ALICE

“Breaking news“

LHC beam test 2021��

ALICE in one minute or less

#CERN #heavy-ions #QGP #~2000people #>350papers #>10 years running

news from ALICE - LHC beam test - October'21

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ALICE version 2.0

Runs 1 and 2: 1 nb^-1 of Pb-Pb collisions

Interaction rate ~8 kHz

readout rate ≈ 1 kHz

Run 3 and Run 4: 13 nb^-1 of Pb-Pb collisions

readout rate ≈ 50 kHz (Pb-Pb), ≈ 1 MHz (pp)

online reconstruction : all events to storage!

LS2 upgrade

• New TPC R/O planes
• New silicon tracker (ITS & MFT)
• New Fast Interaction Trigger (FIT)
• New Online/Offline system (O2)
• Upgrade readout of all other detectors

x50 statistics increase

for most observables

> Improve tracking resolution at low p_T

ALICE-USA

A Large Ion Collider Experiment

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

The ALICE Phase I Upgrade

• Pb-Pb: 13 nb^-1 at 5-5.5 TeV (x 100 wrt Run 2 for MB events)
• p-Pb: 0.6 pb^-1 at 8-8.8 TeV (x1000 wrt Run 2 for MB events)
• pp: 200 pb^-1 at 13-14 TeV (x20-3000 wrt Run 2, depending on channel)

with high-multiplicity and rare probes selection

Target luminosity for Run 3 and 4

ALICE v. 2

ALICE v. 1

ALICE phase I upgrade

ALICE phase I upgrades

• continuous readout and recording

(online data compression based on event reconstruction)

🢧 Improved vertex tracking at low p_T

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Installation of new and upgraded detectors (1)

Installation of upgraded TPC - Aug 2020

Installation of new MFT - Dec 2020

Installation of Miniframe - Nov-Dec 2020

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Installation of new compute farm (O2) – Jan 2021

New: FIT - June 2021

New: Muon upgrade complete - Aug 2021

Installation of new and upgraded detectors (2)

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Doors closed, and ventilation reinstalled

Mission accomplished!

Installation of new and upgraded detectors (3)

PX24 shaft shielding

will be closed before the pilot beam, in w41

Miniframe shielding reinstallation in w47-48

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Global commissioning

Operation crew (2 on site and 2 remote)

Global commissioning ongoing since mid-July: integration of all systems, calibration and alignement

LHC beam test ongoing

🢧 good opportunity for more advanced commissioning and calibration

TRD cosmic tracks

ITS + TPC cosmic tracks

Test of TI2 transfer line - upstream splash muons

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Global commissioning

Operation crew (2 on site and 2 remote)

Global commissioning ongoing since mid-July: integration of all systems, calibration and alignement

LHC beam test ongoing

🢧 good opportunity for more advanced commissioning and calibration

TRD cosmic tracks

ITS + TPC cosmic tracks

Test of TI2 transfer line - upstream splash muons

26th of October: first collisions in ADJUST

ALICE FWD detectors – luminosity meters for LHC - start ‘seeing’ collisions

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LHC Beam test schedule – October 2021

news from ALICE - LHC beam test - October'21

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Configuration:

• Pilot beam (low intensity)
• SPS injection energy (450 GeV per proton beam)

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• Sunday - TBC

ARC occupancy observing anti-COVID-19 measures

ALICE Control Room / P2 ~1 AM @ CERN

A Large Ion Collider Experiment

ITS

news from ALICE - LHC beam test - October'21

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v_z offset from IP v_z==0:

RF lock not tuned

(“cogging”) to be improved in the next fills

A Large Ion Collider Experiment

ITS

news from ALICE - LHC beam test - October'21

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Some inefficiencies to be understood. Calibrations ongoing.

A Large Ion Collider Experiment

news from ALICE - LHC beam test - October'21

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A customary gift from the experiments to the machine staff…

Still tuning of tracking-alignment-event display workflow needed (ITS-TPC matching)

A Large Ion Collider Experiment

TPC ‘time frames’ – as seen by the EPN (synchronous reconstruction) GPU powered computer cluster (at Point-2)

news from ALICE - LHC beam test - October'21

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An early screen shot… : collisions and outgoing tracks clearly seen

A Large Ion Collider Experiment

TPC

news from ALICE - LHC beam test - October'21

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Cluster distribution from quality control plots

… and even dE/dx for tracks

A Large Ion Collider Experiment

Thanks!

news from ALICE - LHC beam test - October'21

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Some background info …

news from ALICE - LHC beam test - October'21

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news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Phase-I Upgrade Completion Cost

ALICE Phase-I upgrade finished On-Time and On-Budget

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

Physics Highlights

http://alice-publications.web.cern.ch/submitted

360 ALICE papers on arXiv

(32 new papers)

Steady stream of scientific publications

360 papers on arXiv, 32 since last RRB meeting

Talks 2019 - 2021

pandemic

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

1002 Scientific Authors

• 575 PhD Physicists
• 372 PhD Students

40 Countries, 173 Institutes (including 18 Associates)

1954 Members, 1002 scientific authors

The ALICE Collaboration

Nr. participants

• 55 Senior Engineers

news from ALICE - LHC beam test - October'21

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A Large Ion Collider Experiment

1954 Members from 40 Countries

Scientific Authors

Active Members

The ALICE Collaboration

ALICE-USA