Physics and Techniques of the Fixed Metal Microstrip ...€¦ · Kharkiv. 15-May-2018. 6 Motivation Heavy ions collisions:. Physics tasks and LHCb achievements. Motivation for the

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Physics and Techniques of the Fixed Metal Microstrip Target

for the LHCb Experiment

V. Pugatch 1,2

1 Institute for Nuclear Research NASU, (KINR)2 EMMI (GSI)

International Conference "CERN-Ukraine co-operation: current state and prospects“

Kharkiv. 15-May-2018

Content

• Introduction

• Physics: QCD at the ~100 GeV NN c.m.s. energy

SEE from metal foils

• TechniquesDetector to search for the QGP signals

Fixed target regime at the LHCb

Metal microstrip detector-target Steering and Luminosity Monitoring

• Summary and Outlook

V. Pugatch. Physics and Techiques Metal Microstrip Target at the LHCb. CERN-UA. Kharkiv. 15-May-2018.

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Success in the Ion Physics and Fixed (Gas) Target studies (SMOG)

-> IFT WG involves in the studies appreciable number of LHCb members

Originated by ‘Proposal for LHCb Participation to the Heavy Ion Runs’ LHCb-INT-2015-019.

J.Blouw , M.Ferro-Luzzi , F.Fleuret , G.Manca , L.Massacrier , K.M¨uller, P.Robbe , M.Schmelling, B.Schmidt, Z.Yang .

In particular: To study the formation of QGP and observe the transition from ”cold” to ”hot” nuclear matter.

The results of the proton-lead run in 2013 -> potential of LHCb – attractive !

(J/Psi – prompt and delayed, Psi(2S), Υ(1S, 2S, 3S), K, lambda, … original exciting results !)

LHCb performs measurements in the forward region with a precision inaccessible by other experiments.

LHCb fixed Gas) target setup (SMOG) :

p-Ar data measured/analysed with encouraging conclusions


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Introduction Motivation Physics tasks requirements and … dreams about ‘NEW’

Motivation for the Fixed Metal Targets in the LHCb Experiment

LHCb detector measuring collisions with heavy ions. Prompt D0 : nuclear modification factor RpPb

PROTON-LEAD COLLISIONS @ 5 TEV


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JHEP 10 (2017) 090 R pPb =1/A * σ pPb/σ pp

MotivationHeavy ions collisions:.Physics tasks and LHCbachievements

LHCb detector measuring collisions with heavy ions.

J/Ψ production in proton-lead @ 8.16TeV


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Nuclear modification factor - from b Nuclear modification factor - prompt J/ΨPLB 774 (2017) 159-178

Remarkable difference!

Illustration of the hot environment impact ?


LHCb contributes in exciting heavy ion program

– proton-lead: pPb data at 5 and 8 TeV: D0 , J/Ψ, ψ(2S) 1 , Λc , Z, …

– lead-lead: 5 TeV

– fixed target physics: unique opportunity with SMOG system (Ar, He, Ne) J/Ψ and D0 in pAr @ √ sNN = 110 GeV

from SPS to LHC physics within a single experiment

LHCb physics covers pp, pA, AA interactions (heavy flavour, electroweak, soft QCD, …


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Motivation for the Fixed Metal Targets in the LHCb Experiment

• LHCb success in the Ion Physics and Fixed (Gas) Target studies

• Fixed Metal Targets: New domains of colliding nuclei and

energies at LHC (~ 80 - 110 GeV, nucleon/nucleon c.m.s.)

• Immense variety of colliding nuclei: enrichment of LHC physics

tasks

QGP signatures (Nuclear Modification Factors)

• possible dependence on ground state properties of colliding nuclei

Nuclear (and possibly atomic) dependence of the quarkonia production

- from N interaction points:

N metal targets in LHC beam, simultaneously.


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Extending range of nuclei and energiesfor heavy ions collisions at LHC)

Immense variety of metal targets-

nuclei (BLUE color in the table):

6,7Li (1+, 3/2-); 9Be (3/2-); 12,13C

(1/2– ,0+); 27Al (5/2+); 46 - 50Ti (0+ -

7/2- ); 56Fe (0 +); 63, 65Cu (3/2- );116, 117, 118, 119, 120 Sn(0+) … up to252Cf

Different ground state properties:

• Isotopes

• Spin and parity

• Deformation

• Closed shells (magic nuclei)

• Neutron skin

• …


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Nucleus-nucleus collisions studied in HEP:

p-p ; p – Pb; p –Au; p – Ne; p – He; d – Au; Pb – Pb; …

Large, yet limited range for knowledge

about an impact of the initial state

on nucleus-nucleus collisions


Impact of the ground state properties on Nuclear Modification Factor ?

• Nuclei in ground state have different shape, angular momentum, …

• Nuclei with closed p-, n-shells (double-magic) are spherical

• Nuclear matter density distribution is not uniform

• Neutron-rich nuclei have large radius

• Neutron excess may create neutron nuclei in collisions ?

https://web-docs.gsi.de/~wolle/TELEKOLLEG/KERN/index-s.html


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https://web-docs.gsi.de/~wolle/TELEKOLLEG/KERN/index-s.html

Different fixed targets behave differently in collisions …

Bullet Time | City Gallery Wellington


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http://citygallery.org.nz/exhibitions/bullet-time

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Nu Xu (STAR Collaboration) QM2014)

Experiment Energy range

(Au/Pb beams)

Reaction rates

Hz

STAR@RHIC

BNL

sNN = 7 – 200 GeV 1 – 800

(limitation by

luminosity)

NA61@SPS

CERN

Ekin= 20 – 160 A GeV

sNN= 6.4 – 17.4 GeV

80

(limitation by

detector)

MPD@NICA

Dubna

sNN= 4.0 – 11.0 GeV ~1000

(design luminosity

of

1027 cm-2s-1 for

heavy ions)

CBM@FAIR

Darmstadt

Ekin= 2.0 – 35 A GeV

sNN= 2.7 – 8.3 GeV

105 – 107

(limitation by

detector)

Ion-Ion relativistic collisionssNN = 2 – 200 GeV

Physics: QCD at the ~100 GeV NN cms energy


Experiments exploring dense QCD matter

Expected (CBM) reconstructed yields for 4 weeks

min. bias Au+Au with 107 beam ions/s (100 kHz events/s):


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A GeV Λ Λ Ξ− Ξ+ Ω− Ω+

10 2.4∙1011 3.8∙107 9.6∙108 2.0∙106 1.3∙107 1.5∙105

Messengers from the dense fireball

UrQMD transport calculation U+U 23 AGeV


P. Senger.Hyperons in Nuclear Matter, GSI, July 22, 2015

http://images.iop.org/objects/ccr/cern/53/4/18/CCfir5_04_13.jpg

Nuclei in ground state have different shape (deformation parameter β), angular momentum, …Impact of charge polarization at initial phase of collisionsPrimary excitation of nuclei – Giant resonances (isovector dipole, isoscalar quadrupole, ….

Neutron excess may create neutron nuclei ?V.M. Pugach, O.F. Nemets. ‘Neutron nuclei and the possibility to identify them in correlation experiments’ . “Exotic Nuclei”, Proceedings International Conference, Foros, Crimea. 1-5 Oct.

1991, World Scientific, p. 149-157). О возможности идентификации нейтронных ядер в процессах трехчастичного развала ядер, Изв. АН СССР, сер.физ. 1984, т. 48, с. 1930-1935

Extension of the range of nuclei

for studies of Nuclear Modification Factor


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sNN = 7 – 200 GeV

Crystalline Targets

Crystall structure – alligned atoms&nuclei –sequential scattering of high energy nucleus:

• Cascade of nuclear interactions – Multiplicity of event– 105-8 - ?

• Fusion to super heavy nuclei ?• Mass-spectrometry, gamma-rays analysis after

irradiation

• Neutron rich or even neutron nuclei production ?

• Scattering at excited short-lived nuclei - new RBF ?

• …


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Crystal lattice nuclei

7 TeV proton


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The LHCb experiment

The LHCb detector – forward spectrometerwith excellent characterisitics• Acceptance 2 < η < 5

• Momentum resolution about 0.5 %

• Track reconstruction efficiency > 96 %

• Impact parameter resolution: ~ 20 μm

• Decay time resolution: ~45 fs

• Invariant mass resolution: ~(10-20) MeV/c2

• Ring-Imaging Cherenkov Detectors and Muon system -particle identification

(ID efficiency > 90%)

LHCb: The Large Hadron Collider Beauty

Experiment for Precise Measurements

of CP-Violation and Rare Decays

p p

RMS


HERA-B - dedicated B-physics experiment (1992 – 2003).920 GeV proton beam at fixed target. DESY (Hamburg)


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p p

LHCb (CERN)HERA-B. 1994 - 2003

ІЯД НАН України – участь в створенні першої в світі 8-точкової системи ядерних взаємодій.V. Aushev, Yu. Pavlenko, S. Prystupa, Yu. Pylypchenko, V. Pugatch, N. Tkach, Yu. Vasiliev, V. Zerkin

LHCb 23d Anniversary, CERN. Nov. 5, 2018

100th Anniversary of the NAS Ukraine – 15th May 2018


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Фізичні цілі LHCb. Міжнародна Колаборація LHCb.

The LHCb acceptance

LHCb-INT-2015-019.

The phase space compared to other experiments has the unique advantage:

- precise tracking /vertexing, calorimetry and powerful particle identification in the full acceptance.

for fixed target running - the acceptance is central to backward.

- AA collisions in fixed target mode with heavy nuclei generate energy densities between those achieved at the SPS and those probed at RHIC:

- - measurements in fixed target and in colliding beam mode will bridge the gap between the SPS and the LHC in a single experiment.

.In fixed target mode it has about the same total central and backward coverage as the PHENIX experiment at RHIC, but without gaps.

p-A Collisions at the proton energy 𝑇 = 7 TeV:

√𝑠NN = 114.6 GeV.


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TechniquesDetector for physics events reconstruction in search for the QGP

Fixed target regime at the LHCb

The geometrical acceptances for 𝐽/𝜓 production : ~8 % at 𝑧 = 0 ~6.0 % at 𝑧 = +50 cm.

http://dx.doi.org/10.1155/2015/760840

http://dx.doi.org/10.1155/2015/760840

Fixed Target regime extends the LHCb physics programme.

QCD phase diagram may have interesting features probed by 10–100 GeV beams on fixed target.

For instance: 𝐽/𝜓, and 𝜓(2S) modification of cross-sections due to hard production and suppression by hadronicdissociation in QGP.

Collect data in p-p (for reference), p-A and A-A heavy-nuclei collisions:

Measure: production cross-sections and the nuclear modification factors ratios, RpA,AA

𝑅AA ≡ 𝑑𝑁AA/𝑑𝑦 / (𝑑𝑁pp/𝑑𝑦 ⋅ ⟨𝑁coll⟩)

RpA,AA different from 1

indication that the QGP modified the production ratios

- Data taking time (example):- The p−Ne data: dedicated run of one week per year (corresponding to 1.5 pb−1) - the Pb−Ne in parallel with the PbPb collisions (24 days or 0.7 nb−1 per year).


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TechniquesDetector for physics events reconstruction in search for the QGP

Fixed target regime at the LHCbFixed target regime at the LHCb

Wire-Target in the LHC ion beam halo.

presenting also results of fruitful discussions with

Michael Schmelling, Frederic Fleuert, Patrick Robbe, Guilia Manca, ZHU Xianglei, Richard Jacobsson, Jorg Wenninger, Stefano Redaeli, Giacomo Grazziani and others.


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Similar system operated successfully at HERA-B.

Physics goals are natural extension of SMOG heavy-ion programme.

Advantages include higher event rate & possibility toaccess wide range of nuclei.

Key topics include studies of nuclear modificationfactors & nuclear dependence of quarkoniaproduction.”

Data taking would take place in short dedicated runs.

ChargeIntegrator

Proton beam

Existing readout hardware/software(RMS@IT-2) could be used for steeringwire targets

Techniques:Metal microstripdetector-target Steering of the targetsLuminosity monitoring

Techniques of Multi-Target setup.HERA-B experience, p-A scattering, p- 920 GeV – 40.6 GeV – c.m.s.)

Principle: Metal wire-targets move in/out of the proton beamhalo – to provide Interaction rate (luminosity) equallydistributed among the targets.

Luminosity Equalization: Target – Metal Detector Steering of the target position

by the charge generated in it due to SEE initiated by the incident proton beam


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SEE Physics/Techniques:SEE from metal foilsMetal microstrip detector-target

Equalization of the luminosities Charge Integrated in Individual Targets -data for the steering feedback system at HERA

Proof of the principle – Vertices are equally distributed over inserted targets.8 targets simultaneously could be handled providing 40 MHz interaction rate

http://dx.doi.org/10.1063/1.1291460

Eight targetsFour targets

12C

Pd

48Ti

Al

48Ti

W

12C

12CP-beam


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Techniques:Metal microstripdetector-target Steering of the targets

http://dx.doi.org/10.1063/1.1291460

Manpower and expertise are required .HERA-B Target Group (1994-2004)

Dortmund University & Kiiev Institute for Nuclear Research (KINR)

Two professors, 4 postdocs, 7 PhD students +!Support & Collaboration with the VDS (MPIfK, Hd) group and HERA accelerator


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100th

Anniversary of the NAS Ukraine – 15th May 2018

Physics results with metal targets at HERA-B. Example: Nuclear Dependence of J/ψ production at HERA-B.


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Update of Wire-Target Proposal

LHC expert (JW) view:

‘No way for the target to get out of the collimator shadow. Please, forget HERA, the LHC is another dimension in terms of beam intensity, stored energy and quench criticality.’

’ – The only allowed object on the beam way – COLLIMATOR.’ – principle of safety against superconducting magnets quenching, radiation damage of physics detector etc.,

‘At low intensity one can obviously do many things, including such a wire’

MTS Proponent view/question:

Is there any possibility to fulfil the requirement of safety principle with wire –target?

Yes: make such metal wire target setup that it generates fluxes/fluences at the same order

of magnitude as it occurs in A-A colliding mode:

LHCb nominal luminosity for p –p collisions -> 2* 1032 cm-2 s-1


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Transformation of the wire target proposal:Micro-wire target thin enough

to move from the halo to the core of the beam !

• Discussions are on the way on safety issues regarding affordable luminosities (from the LHC and the

detector side).

• Superthin Wire Targets (SWT) is under consideration .

• Let us assume the affordable instantaneous luminosity of 1028 cm-2 s-1 for the Pb(beam)-Ni (target)

collisions.

Inserting 1 mum thick (5-50 µm wide) Ni microstrip target into a Pb beam with 500 bunches (108 ions in each) at the

distance of ~3 beam sigma (effective width of 200 µm) one would be close to the above mentioned luminosity.

The SWT target may reach the beam core and be melted.

Even in such case the luminosity will not exceed limits for normal operation of detector as well as LHC

magnets. After that the next strip of the target will arrive into the operational position in a beam to

continue the experiment without interruption.

• This is how it could be started.

Depending upon the test studies, one could evolve with the SWT setup for the real experiment.


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Practical realization. Metal Microstrip Detectors (MMD)–technology.


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MMD is produced at KINR exploring the plasma-chemistry reactor with adjustable energy of ions Completely removing Si-wafer in the operating window Leaving there 1-5 μm thick metal strips undamaged.

This technology has been successfully explored for the MMD production with up to 1024 strips (10 … 200 μm width, up to 8 mm long) surviving during long term of conservation and operation.

Techniques:Metal microstripdetector-target

SWT- HOW-TO-DO it at LHCb (proposal)for the best realization of all benefits of the LHCb detector. (LS3 ?)

Location at VELO

Microstrip Targets region ?


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Multi-target setup at LHCb ? VELO – VErtex Locator construction after upgrade


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Techniques:Metal microstripdetector-target

UHV compatibility: < 10 -9 TorrSupporting frames – Si wafersSignal output – micro-cablesCharge Integrators for readoutSEE – operating voltage – + 20 V

Technical Realization Option.Metal microstrip target-detector in VeLo – metal fixed target LHCb setup

The most natural (as well as straight and forward!) position of the target –LHC Interaction Point 8:

inside the Vertex Locator (VeLo). Namely, one of the veto plane might be considered.

Obvious peculiarity – instead of ~ 13 cm (LHC bunch length) long interaction region - one gets really interaction point – 1 µm long, only !

This may lead to new ideas how it could be explored for physics analysis (reduction of background, improvement of accuracy in vertex reconstruction, etc.)


30

Microstrip MetalTarget -Detector

Multi-target setup at LHCb VELO – VErtex Locator construction after upgrade



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Superthin Wire Target - HOW-and When TO-DO it at LHCb ?VELO – VErtex Locator construction after (LS3 ?) upgrade


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Metal Microstrip Detector –MMD-1024.

Nano-technologies evolve fast– already nowadays- carbon nano-tubes,fullerene structures, graphenes, …

May become a nano-wire target components.


Metal Foil Detectors in RMS at Inner Tracker -existing readout infrastructure for steering metal microstrip targets


RMS design, construction, commissioning, running RadiationMonitoring System - in Collaboration with colleagues from MPIfK(Hd), Zurich University, LPHE (Lausanne), CERN (Richard Jacobson,Federico Alessio, Gloria Corti)

Operational readout hardware/software for steering metal

microdetectors- targets

Just connect targets-detectors to the spare Charge

Integrator in the LHCb bunker.RMS rates vs the LHCb luminosity with in 2016( points - different fills) – perfect linear response


http://images.iop.org/objects/ccr/cern/53/4/18/CCfir5_04_13.jpg

Events with three nuclei interaction !• Intriguing opportunity with metal microstrip target – never explored in earlier experiments !• Might be very interesting phenomenon – what is the interaction energy of three nucleons (two from LHC

beams and one from the fixed target) ?

• What will be the Equation of State ?• Which temperatures and densities of the hot matter part might be ?

Three-nuclei interaction– two nuclei from LHC beams

and one from the LHCb Microstrip Target


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Beam 1Pb

Beam 2Pb

Fixed TargetPb

LHCb Super Thin Metal Microstrip Targets steering

Two methods to steer targets by feedback system exploring:

Charge integrated in individual target

Vertices reconstructed by the VELO (HLT-2)

The steering code handles fast beam finding, rate stabilization, the rate equalization among several targets and emergency situations:

• no harm to the beam or detectors

• high reliability and safety have the highest priority in the steering concept. The main steering runs in a 10 Hz loop.


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Some beneficial features of the LHCb Metal Microstrip Fixed Target setup

• Physics

Extension of the nuclei range for Nuclear Modification Factor studies

(including isotopic enriched targets)

Impact of the individual nuclear properties (nuclear shell effects, spin, parity, deformation) on quark-gluon plasmageneration

Nuclear Modification Factor for neutron-rich nuclei

Search for Neutron nuclei

…

Technique:

Well localized interaction region (about 100 µm)

Taking data for many targets in a single Run

– errorless relative comparison of physics data

Perfect tuning/monitoring of the individual luminosity

Safe and reliable operation


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Current resourses (encouraging!)

Interest of the LHCb IFT and LHC PBC Working GroupsEvaluations and requests from the LHCb FITPAN

Financial support by the NAS Ukraine (budget and grants).

High Energy Physics

• Maryna Borysova

• Tetyana Obikhod

• Maksym Teklishyn

• Oleksandr Okhrimenko

• Serhii Koliev

• Vasyl Dobishuk

• Mykhailo Pugach

• Igor Kostiuk

• Evgenii Petrenko

• Kateryna Trohymchuk

Detectors development and Applications

• Olexii Kovalchuk

• Andriy Chaus

• Victor Iakovenko

• Victor Militsiya

• Dmytro Storozhyk

• Volodymyr Kyva

• Evgenia Momot

• Iaroslav Panasenko

• Tetyana Pugach

37V. Pugatch. Physics and Techiques Metal Microstrip Target at

the LHCb. CERN-UA. Kharkiv. 15-May-2018.

KINR Team. HEP Department

• There are good physical and technical reasons to build the Metal Microstrip Fixed -Target (SWT) Setup at LHCb• KINR group will contribute in designing and building the SWT setup.

• The Superthin Wire Target is a challenging project .

We shall search for the ways to overcome the challenges.

Its realization is not excluded even if the target (superthin microstrip one or …) is getting status of the

primary object for the LHC beam

One has to work out the safe mode of operation of the complex setup 'beam-target'.

• The SWT project (the metal microstrip detector as a target in LHC beam) is underdevelopment at KINR. Welcome to join this activity !

• It was more than one time in the experimental physics: what looked impossible yesterday wassolved today. And major sense in this activity is a chance to discover new physics events withsuch targets.

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Summary and Outlook


Acknowledgements

• LHCb Collaboration

• IFT WG members

• FITPAN members

• LHC experts

These studies were carried out in frames of the LIAIDEATE activity.

Related project (ЦО-1-7-2017) has been financiallysupported within the Programme of the NASUkraine for development of further cooperationwith CERN and JINR «Nuclear matter in extremeconditions».


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Acknowledgements

• Many thanks to FITPAN members for stimulating interest and questions.

• General discussions at the IFT WG Meetings were fruitful.

• Contributions from Michael Schmelling, Frederic Fleuert, Giulia Manca wereconstructive and inspiring.

• Discussions with Patrick Robbe, Richard Jacobsson, Francesco Bossu, GiacomoGrazziani and other IFT WG members are highly appreciated.


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Thank you for your attention!

41V. Pugatch. Physics and Techiques Metal Microstrip Target at

the LHCb. CERN-UA. Kharkiv. 15-May-2018.

Welcome to Kyiv !

FITPAN, Q2. Data taking in parallel with pp physics may be difficult. In this case dedicated runs would be needed. It is important to understand how long these dedicated runs would need to last. Please tabulate some of the key measurements and for each estimate how much data are required, and how long it would take to accumulate these data in dedicated or parallel running mode.

Assuming that the wire sees 10^9 protons/sec:- on a 100 um thick Pb target, the instant luminosity should be ~0.3 ub-1.s-1 = 3x10^29 cm-2.s-1.- for a 10h fill, integrated luminosity = 0.3 x 36000 = 10 nb-1.

- based on phys.let B638:202-208, 2006, at 110 GeV, we expect sigma_psi~1500 nb/nucleon * Br(-mumu)=5.9% * A=207 =18320 nb.- LHCb sees half of the phase space with an efficiency ~10%, so 18320 * 0.5 * 0.1 = 916 nbFinally, in a 10h fill with 10^9 POT/s, we should record (on tape) 916*10 ~ 9000 J/psi

• Considering Pb beams, with 10^5 Pb ions/sec out of 10^10 ions in the beam, one would record in 10h, ~0.1 nb-1 leadingto 90 * 208 ~ 18 000 J/psi. With 1/4 of the nominal number of bunches, one get 4500 J/psi (one can safely expect ~20fills in a one-month run, so ~90 000 J/psi total).

More details in refs:

https://arxiv.org/pdf/1504.05145v2.pdf

http://arxiv.org/pdf/1510.03976.pdf


42

https://arxiv.org/pdf/1504.05145v2.pdf

http://arxiv.org/pdf/1510.03976.pdf

GW - ‘How would the data-taking proceed in relation to standard LHCb running? Could it be in parallel, or would it require dedicated operation ? If the latter, how much time would be required, and under what conditions ?’

N.S.Topilskaya ISHEPP_XXIII, 23 September 2016. A.B. Kurepin and N.S.Topilskaya

‘Heavy ion collisions in a fixed target mode at the LHC beams.’

Luminosity and counting rate estimation for J/ψ production (Lead, wire ribbon).

500 µm (thickness) , 3.2 ∙ 10 11 protons (7 TeV)/60 min


43

Pb-Pb 71.8 GeV I= 7.97 % L = 2.2∙1027 cm-2 s-1 378 J/ψ per hourp-Pb 114.6 GeV I=5.98 % L =1∙1029 cm-2 s-1 112 J/ψ per hour

Our measured result in HERA-B:

With 4 targets in the halo of the proton beam (at ~4 sigma) –

Luminosity about 1033 cm-2 s-1 was reached with the proton lifetime about 50 h.

Taking into account the affordable for the LHCb detector occupancies –

the instantaneous luminosity may be increased by factor of up to 10-20

Resulting in production of few thousands of J/ψ per hour

FITPAN, Q6. A study of possible triggers would be desirable, especially in the case of concurrent running with pp collisons.

• Rather than concurrent running with colliding beam mode, it may be better to dedicate short runs from a regular fill to wire target running.

• In this case the well understood minimum bias and muon triggers could be used and there is no interference with other physics. Interaction rates of O(107) eventsper second (103 bunches x 104 revolutions/second) are certainly feasible, i.e. taking as a rule of thumb that 10^14 collisions correspond to fb-1, a less than one hourrun with O(1010) interactions would accumulate 100 nb-1, i.e. about 5 times more than the total of SMOG data collected in so far.

Dedicate one short run from a regular fill to wire target running.

• The luminosity can easily be tuned

• The data taking rate of 10^8 events/hour :

a simple trigger is needed on beam-1, only.

The main point of this setup is the possibility to quickly change between colliding beam and fixed target physics, without e.g. side-effects on the vacuum, but with highrated and a very localized interaction point.

All that’s needed is to load a new trigger TCK and start a run.


44

FITPAN, Q10 Demonstrator of Solid Targets in LHCb. Technical Realization. Phase -1

When ?

Phase -1. Feasibility and Physics studies. EYETS – 2018 (?) : KINR team (Oleksandr Okhrimenko, Igor Kostiuk, Oleksii Kovalchuk, Serhii Koliiev, Vasyl Dobishuk,

Valery Pugatch, Kateryna Trohimchuk) provides:

technical design report (one month)

construction and preliminary tests (two months)

installation and commissioning (one month)

final test (one month)

Writing documentation for running STS demonstrator (one month)

in collaboration with colleagues from IFT WG, VELO, LHC machine under supervision by Technical Coordinator, in total – 6 months.


45

The Chiral Magnetic Effect and anomaly-induced transport

Dmitri Kharzeev. Progress in Particle and Nuclear PhysicsVolume 75, March 2014, Pages 133–151

The Chiral Magnetic Effect (CME) is the phenomenon of electric charge separation along the external magnetic fieldthat is induced by the chirality imbalance. The CME is a macroscopic quantum effect — it is a manifestation of thechiral anomaly creating a collective motion in Dirac sea. Because the chirality imbalance is related to the globaltopology of gauge fields, the CME current is topologically protected and hence non-dissipative even in the presence ofstrong interactions. As a result, the CME and related quantum phenomena affect the hydrodynamical and transportbehavior of systems possessing chiral fermions, from the quark–gluon plasma to chiral materials. The goal of thepresent review is to provide an elementary introduction into the main ideas underlying the physics of CME, ahistorical perspective, and a guide to the rapidly growing literature on this topic.

===============================

Dmitri Kharzeev. Chiral Magnetic Effect. Physics Letters B 633 (2006) 260–264

The multiplicity per unit of rapidity in RHIC Au−Au events typically varies within the limits 100 Nπ+ 300. The expectedmagnitude of the asymmetry (11) is thus Aπ+ ∼ 10−2.

The arguments for the possibility of violation of P and CP symmetries of strong interactions at finite temperature arepresented. A new way of observing these effects in heavy ion collisions is proposed—it is shown that parity violation shouldmanifest itself in the asymmetry between positive and negative pions with respect to the reaction plane. Basing ontopological considerations, we derive a lower bound on the magnitude of the expected asymmetry, which may appear withinthe reach of the current and/or future heavy ion experiments.


46

http://www.sciencedirect.com/science/journal/01466410

http://www.sciencedirect.com/science/journal/01466410/75/supp/C

Needle Targets at the halo of the LHC beam

Movable Up&Down platform

LHC BEAM

Ni-64 Ni-58 Pb-208 Cf-251

2.5

mm

+/-

10

0 µ

m


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Physics and Techniques of the Fixed Metal Microstrip ...€¦ · Kharkiv. 15-May-2018. 6 Motivation Heavy ions collisions:. Physics tasks and LHCb achievements. Motivation for the

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