s d

+K E. Iacopini, CSN1 Napoli 20 Sett. 2005E. Iacopini, CSN1 Napoli 20 Sett. 2005

• Stato della CollaborazioneStato della Collaborazione (A. Ceccucci)

• Disegno dell’apparato sperimentale Disegno dell’apparato sperimentale (N. Doble, L. Gatignon)

• Stato della simulazioneStato della simulazione (G. Ruggiero)

• Dove siamo con i detectorsDove siamo con i detectors

• Proposal submitted to SPSC on

June 11, 2005:“We propose to measure the very rare decay

K+ + at the CERN SPS to make a decisive test of the Standard Model by extracting a 10% measurement of the CKM parameter |Vtd|.”

• The open presentation to the SPSC is scheduled on September 27, 2005

Recent developments in the rare kaon decay community

• A few months ago the Fermilab Directorate endorsed the PAC recommendation not to pursue K+ + at the Main InjectorThe physics of K+ + was considered very important but a

potential conflict for protons between the kaon and the neutrino possible programmes at Fermilab lead to this recommendation

• Very Recently the RSVP program was terminated:– The to e conversion experiment (MECO) and the K0

experiment, ready to start construction at BNL, will not be built

• This leaves CERN and Japan (JPARC) as the only places where an ultra-rare kaon decay experiments are currently envisaged

• However, to be completely fair, one should also mention:– Plans at Protvino as mentioned at KAON2005– Plans at Frascati to study KS at an upgraded phi factory

Strengthening P326• The demise of the US kaon program has triggered

negotiations with members of KOPIO/CKM to join P326• The following groups have signed up since the proposal

submission:– S Louis Potosi (Mexico, J. Engelfried)– Bolotov’s group (Moscow, INR)

• Interest to join has been expressed by the following groups:– Fermilab (P. Cooper) – BNL (L. Littenberg)– British Columbia (D. Bryman)

• However, a possible participation of US groups is subject to: – DOE support towards a strong contribution to the

construction of the detector (notably the RICH counter)– The involvement of US Universities in addition to

National Labs (at least for BNL)

Endorsement of P326 R&D by SPSC

• From the draft minutes of the July 05 meeting:

"The SPSC considers it important that an R&D programme continues concerned with the possibility of an experiment to measure the rare decay K++ "

CERN Program and Plans

introduction to Round Table discussion onThe Future of High Energy Physics

ECFA-EPS Joint Session at HEPP-EPS 2005International Europhysics Conference onHigh Energy PhysicsLisbon, July 21 -27, 2005

Jos EngelenCERN

2004 2005 2006 2007 2008 2009 2010

LHC ExperimentsALICEATLASCMSLHCbTOTEMOther LHC Experiments(e.g. MOEDAL, LHCf)

Non-LHC Experimental ProgrammeSPSCOMPASSNA48NA60Neutrino / CNGSNew initiatives

OTHER FACILITIESADISOLDEn-TOF NeutronCASTDIRACTest Beams

North Areas

West Areas

East Hall

R&D(Detector & Accelerator)

Legend: Approved Under Consideration

PS

an

d S

PS

Sh

utd

ow

n

From Medium Term Plan, CERN/2615

•Will determine the future course of high energy physics•Detector completion/upgrade/in particular for luminosity upgrade ( 1035) (~2014); requires R&D, machine and detectors

•Very limited neutrino programme (in scope)•New initiatives include K++; why not K00..?•New initiatives may include a long term neutrino programme•CERN working groups Proton Accelerators for the Future (PAF) and Physics Opportunities at Future Proton Accelerators (POFPA)•New initiatives to appear in Budget Plan from 2006 (or maybe 2007) onwards

•Accelerator R&D includes EU funded networks, joint projects, design studies•Linear colliders: Eurotev (‘generic’) and CLIC (CERN and partners, ‘collaboration’, feasibility proof by 2009)

EURISOL Design Study (including beta beams)

No fully-fledged Neutrino Factory Design Study yet (2008 if EU support)

Slides from Niels Doble & Lau GatignonSlides from Niels Doble & Lau Gatignon

Choice of K+ momentum:

(for 400 GeV/c proton momentum)

40 50 60 70 80 90 100 110 120 130 140 1500

1

2

3

4

5

6

7

8

9

10

11

12

13

Acceptance

K+ flux/ 3 1012 inc.p)

/ Total beam

K+ decays in 50 m/ Total beam

Acc. K+ to

K+ / Total beam

K+ / +

/ 3 1012 inc. p

K+ decays in 50 m

x 10-1

x 108

x 10-14

x 10-3

x 10-2

x 10-2

x106

K+ momentum [GeV/c]

(2 RMS)

800 MHz(/K/p)

Solo i rivelatori upstream sono esposti a 800 MHz di fascio (8.6% K) …

10 MHz Kaon decays

K+ +

1.51.5

Thanks to Giuseppe RuggieroThanks to Giuseppe Ruggiero

Background kinematically constrained

Decay BR

K2 0.634

+0 0.211

++- (00)

0.070

92% of total background+0 forces us to split the signal region

Background not kinematically constrained

Decay BRKKe3e3 0.049

KK33 0.033

KK22 5.5×10-3

++00 1.5×10-3

KKe4e4 4×10-5

KK44 1×10-5

8% of total background Spoils the signal region

Background rejection

Goal of P326: S/B ≈ 10 ~1012

rejection

2-steps background rejection:1) Kinematical rejection

Region I: 0 < m2miss < 0.01 GeV2/c4

Against K2, +0

Region II: 0.026 < m2miss < 0.068 GeV2/c4

Against +0, ++, +00

2) Veto and Particle ID, , charged particles

– e separation

Sources of background

Kinematical rejection inefficiencyResolution effectsNon gaussian tailsBeam pile – up

Veto and particle ID inefficiencyRICH – veto – veto

Simulation (Jurgen)

Simulation (Oleg)

Parameterization (Simulation in progress by Rome)(Data in progress: LKr by NA48/2, ANTI by Frascati)

Simulated using FlyoSimulated using GEANT4Simulated using Flyo

Resolutions (Flyo MC)Gigatracker

300 x 300 m pixels0.4% X0 per SpibesSimple reconstruction2% inefficiency per station

Double Spectrometer

80m resolution in X and Y hits (125 m per view)0.5% X0 per chamberTrack momentum from fitAngle from first 2 chambersFully efficient

+0 m2miss

resolution

PK

K

Ptrack

K

Results: (PK)/PK = 4.2 x 10-3

(K) = 16.7 rad

(P)/P = 0.23% + 0.005% P (GeV/c) (K) = 60 – 20 rad (P = 10 – 50

GeV/c)

Veto and particle ID

RICH (Simulation by Jurgen):

17 m long, 1.0 atm Ne

– Veto (Geant4 simulation by Oleg):

-veto = 105

E range Inefficiency

ANTI

< 50 MeV 1

(0.5, 1) GeV

104

> 1 GeV 105

LKR

< 1 GeV 1

(1,3) GeV 104

(3,5) GeV 104 105

> 5 GeV 105

IRCsSAC

All 106

– Veto: inefficiency parameterization

JURGEN

Some general remarks …

Kaon Flux: 4.8×1012 decay/year in the fiducial region

Detector Layout as described in the proposal:Straw chambers 5cm inner radius displaced in x, according to the positive beam deflection in the spectrometersMagnets of the double spectrometer:

MNP33 – 1 Ptkick = 270 MeV/c

MNP33 - 2 Ptkick = -360 MeV/c

All the expected background given per 1 year of data taking

Selection (1)Number of tracks

1 positive downstream track (hit in all the 6 chambers)Choice of the upstream track using minimum 2 (t, cda)

Detector geometryDownstream track inside of the detector acceptance:

Straws: 10 cm < Rtrack < 85 cm (centered on the hole of the chamber)RICH: 12 cm < Rtrack < 120 cm (both on front and back surfaces)

LKr: Octagonal outer shape and Rtrack > 15 cm

MAMUD: square shape, 260x260 cm outer, 36x30 cm inner (front and back)

Particle IDNot muons in RICH or MAMUDNot electrons in RICH or LKr (LKr with 10-3 inefficiency of e – ID)

Selection (2)

Fiducial decay region5 m < Zvertex < 65 m (from the final collimator, Zvertex defined as the Z coordinate of the point closest to both the tracks)

Specific cutsPtrack/Ptrack < 2.5×(P)/P (against the not gaussian tails)

CDA < 0.8 cm (against the tails from the beam pile – up)

KinematicsREGION I: 0 < m2

miss < 0.01 GeV2/c4

REGION II: 0.026 < m2miss < 0.068 GeV2/c4

Cut on momentum15 GeV/c < Ptrack < 35 GeV/c

Acceptance after all the cuts: Acc=(8 ± 2) × 106

Same procedure as for +0 to extract the acceptance

Expected events:N(K2) = kaon × BR × Acc × Rich() × MAMUD() = (1.2 ±

0.3) / year– Region I: 1.1 / year– Region II: <0.1 / year– Nngaus ~ 0.4 / year, Npileup ~ 0.8 / year

Muon veto inefficiency:MAMUD() = 105 (MAMUD)

RICH() = 5 × 103 (RICH) (conservative)

Assumption: MAMUD and RICH rejection inefficiencies independent

+0

Acceptance after all the cuts: Acc = (1.3 ± 0.1) × 104

Assumption: independence between kinematical rejection inefficiency (kin) and selection acceptance

NI,II = kin×Nsel(Flyo)+Npileup(Flyo)

NI,II = Number of expected events in regions I and II after all the cuts

Nsel(Flyo) = number of events selected in Flyo before the cut on m2miss

Npileup(Flyo) = number of events in Regions I and II due to the beam pileup

Acc = NI,II / Ngen(Flyo)

Expected events:N(+0) = kaon × BR × Acc × (0) = (2.7 ± 0.2) / year– Region I: 1.7 / year– Region II: 1.0 / year– Nngaus ~ 0.5 / year, Npileup ~ 2.2 / year

Photon veto inefficiency:(0) = 2 × 108

Two body background vs Spibes performances

K2 K2

+0+0

TotalTotal

Spibes ineff(t) Spibes ns

2 body background events 2 body background events

Other backgrounds

Ke3:Acceptance ~12% (Flyo)0 ~ 3×108

Positron ID: LKr × RICH < 103 × 103 (conservative)

NEGLIGIBLE

K3:Acceptance ~17% (Flyo)0 ~ 3×108

Muon ID: RICH × MAMUD < 105 × 102 (conservative)

NEGLIGIBLE

+00:High suppression from kinematics and vetoNEGLIGIBLE

Signal Acceptance

Selection applied on events generated with FF (from CMC)

Effects not taken into account:Random vetoAccidental loss due to hit multiplicity cutsStraw inefficiencyLoss due to cuts in MAMUD for muon ID

BR(+)=8×1011 (SM)

Signal Acceptance

ResultsREGION I: (4.10 ± 0.03) × 10-2

REGION II: (12.88 ± 0.05) × 10-2

Total: (16.98 ± 0.06) × 10-2

Acceptance normalized in the region: 5 m < Zvertex < 65 m

Most important cutsNtrack=1: cuts 8% of events

Geometry: cuts 10% of eventsMomentum: cuts 50% of eventsPile – Up: cuts 12% of events

Signal and backgrounds / year

Total Region I Region IISignal ~65 ~16 ~49

+0 2.7±0.2 1.7±0.2 1.0±0.1K2 1.2±0.3 1.1±0.3 <0.1

Ke4 2±2 negligible

2±2

++ and 3-tracks 1±1 negligibl

e1±1

+0 1.3±0.4 negligible

1.3±0.4

K2 0.4±0.1 0.2±0.1 0.2±0.1Ke3, K3 negligibl

e

Total bkg

9±3 3.0±0.2 6±3

Beam Line (CERN) CEDAR (CERN) GIGATRACKER (CERN, INFN, Saclay [kabes]) VACUUM TANK (Common fund) ANTI Counters (INFN) STRAW TRACKER (DUBNA, MAINZ) MNP33/2 (Common Fund) CHOD (INFN) RICH (US? + Mexico) LKR (CERN+INFN) MAMUD (INR+Protvino) SAC + IRC (Sofia) Trigger & DAQ (CERN+INFN+?)

A. Ceccucci August 31 2005 - CambridgeA. Ceccucci August 31 2005 - Cambridge

Tentative sharing of construction responsibility (sept. 05)

Abbiamo, molto schematicamente, due problemi:Abbiamo, molto schematicamente, due problemi:

• Politico:Politico:la Collaborazione ha bisogno di rinforzarsi.la Collaborazione ha bisogno di rinforzarsi.

Ci sono stati notevoli passi in avanti nel 2005, come discusso Ci sono stati notevoli passi in avanti nel 2005, come discusso all’inizio, e comunque noi continueremo su questa strada …all’inizio, e comunque noi continueremo su questa strada …

• Tecnico: Tecnico: siamo in grado di installare i rivelatori che ci servono?siamo in grado di installare i rivelatori che ci servono?

Per questo abbiamo un Per questo abbiamo un programma di R&Dprogramma di R&D per tutti i per tutti i nuovi rivelatorinuovi rivelatorie per validare quanto resta dei vecchi (il e per validare quanto resta dei vecchi (il LKrLKr …) …)

Il 27 settembre, verrà presentata all’SPSC, insieme alla Il 27 settembre, verrà presentata all’SPSC, insieme alla Proposta P326, una contestuale richiesta di 30 gg di run per Proposta P326, una contestuale richiesta di 30 gg di run per il 2006, sulla solita linea di fascio K12, principalmente peril 2006, sulla solita linea di fascio K12, principalmente per

- misurare l’inefficienza di osservazione dei fotoni con il LKr- misurare l’inefficienza di osservazione dei fotoni con il LKr

- misurare il fondo da - misurare il fondo da /K interagenti con il gas residuo/K interagenti con il gas residuo

- determinare l'alone del fascio- determinare l'alone del fascio

- effettuare i tests necessari sui prototipi dei nuovi rivelatori - effettuare i tests necessari sui prototipi dei nuovi rivelatori (Cedar, hodo, sensori gigatracker …)(Cedar, hodo, sensori gigatracker …)

R&D R&D sui rivelatori sui rivelatori

di nostra pertinenza:di nostra pertinenza:

HodoscopioHodoscopioVeto dei Veto dei

GigatrackerGigatracker

L’idea è quella di usare Glass Multigap RPCs, sullo stile di quanto realizzato in ALICE

A questo rivelatore infatti è richiesto di essere efficiente (>99%) e di avere un’ottima risoluzione temporale (50ps)in modo da ridurre al massimo la possibilità di associazioniaccidentali fra il pione di decadimento ed il K che lo origina.

FI-PGFI-PG

ALICE detector layout

2 anode and 1 chatode PCB with picup pads

5+5 250 m gaps filled with gas mixture

1 cm honeycombs panel for mechanical stability

96 pads per module readout with 32 flat cable

Differential signal send to interface card

13x120 cm2 area for each module

7x120 cm2 active area for each module

Greater number of gaps

Lower HV (+6.5 kV, -6.5 kV)

Signal amplitude greater of a factor 2

Front-End electronics

ALICE has developed for this purpose, fast (1ns peaking time) front-end amplifier/discriminator (NINO). Each NINO can handle 8 channels.

The input is low impedance (40-75 Ω) differential, and the output standard is an open-collector LVDS (Low Voltage Differential Signal).

NINO can respond to another signal immediately (few ns) after the end of a previous signal (almost no dead time).

On each front end card 3 NINO chip are mounted so the card can

handle 24 channels

The NINO ASIC

bonded to the PCB

MRPC performance

Efficiency > 99%Time resol. < 50 ps

Test performed with the ALICE TOF rate 50 Hz

Rate tests at GIF

The MRPC were tested for efficiency up to a rate of 1.6 kHz

The performance seem to be stable only using an effective voltage of 11.4 kV

The MRPC were tested for time resolution up to a rate of 1.6 kHz

The time resolution seem to decrease a little bit

The resolution at 1.6 kHz is well above 100 ps

This performance are very suitable for P326

New high rate test are mandatory to validate performance up to 5 kHz

Ageing test at GIF

Irradiation with 7∙109 particles/cm2

The performances seem to remain stable in time

The total amount of irradiated charge is equivalent to only 140 days of P326 run:

)(2

9

3261

86400*/

107daysRUNP

cycledutycmrate

Cathode -10 kV

Anode 0 V

(-2 kV)

(-4 kV)

(-6 kV)

(-8 kV)

Signal electrode

Signal electrode

We stick as much as we canWe stick as much as we canto the Alice design, howeverto the Alice design, howeverto reduce material, we areto reduce material, we areplanning a single stack layer.planning a single stack layer.The time resolution, according The time resolution, according to experts, should go from to experts, should go from ~~40 ps to 40 ps to ~~80 ps80 ps

G MRPC for P326

The new PCB for P326• The PCB design used by ALICE is not suitable

for P326:– The connectors on each side introduce too much

dead space between two modules– It’is very difficult to bring signals out of the detector

using ALICE configuration– The material budget would not be uniform due to

connectors and cables

• We are working on a new PCB layout, assuming – Connectors only at the end of each module– Each module is single-layer

Where we are

• First prototype assembly foreseen in late november

• Cosmic ray test will be done, hopefully, within 2005

• Test of efficiency and time resolution at high rate are mandatory to validate the possible use of such a detector in P326: test envisaged with NA48 test-run facility in 2006.

• We are now investigating the possibility of performing the rate test, using some existing ALICE modules at some beam facility, to be found.

• Must achieve inefficiency < 10-5 to detect photons above 1 GeV, and thishas to be tested in 2006.

• It has also to be evaluated the effect on the inefficiency of the material in front of the calorimeter (RICH, hodoscope, windows, etc)

• Advantages:– It exists – Homogeneous (not sampling)

ionization calorimeter– Very good granularity (~2 2 cm2)– Fast read-out (Initial current,

FWHM~70 ns)– Very good energy (~1%, time ~

300ps and position (~1 mm) resolution

• Disadvantages– 0.5 X0 of passive material in front

of active LKR– The cryogenic control system

needs to be updated– Needs a new readout

Large angle vetoes The detector must be able to veto

0s, with energy in the range

40-65 GeV, at the 10-8 level.

This means that it must possess an average veto power on the single photon of the order 10-4

Two technologies are to be compared: Tiles a la CKM Spaghetti a la KLOE

Extensive Geant4 simulation started to study both solutions as far as punch-through, inefficiency dependence from the hitting angle, energy and position, … are concerned.

But also to be comparedCostsMechanical design of the support …

LNF, NA, LNF, NA, PI, RM1PI, RM1

Tile and KLOE geometry1 mm

1 cm

Aluminum ScintillatorLead

27.7

5cm

42.5 cm

30

cm

22/16/16

29

.9

cm

Beam Axis

1 cm

1 mm

2.5 m

24 c

m

The CKM prototype at FNALFormer CKM physicists interested in joining us.

A lot of R/D was already done for CKM vetoes.

A prototype (2 sectors, 80 layers, 1mm/5mm) exists at FNAL, tested in an electron beam. Results are published: Inefficiency for electrons @ 1.2 Gev/c 3*10-6

In 2006 we would like to arrange in Frascati a comparative test with it and a KLOE prototype, to be built.

The Protvino prototype– Protvino has the know-how for

scintillator production

• They have bought all the manufacturing equipment for scintillator from Uniplast (in Vladimir)

– Extruded scintillator– Molded scintillator– Intended to be used for CKM (Kplus)

and KOPIO• Interested to collaborate.

– A 20 layer prototype already available,

– Full prototype under consideration

• Opportunity to use this facility for P326• Need discussion, inspection, agreement,

control, etc..

Test con elettroni del prototipo “KLOE” già iniziati …

• Presa dati con Elettroni da Presa dati con Elettroni da 480 MeV480 MeV, , alla BTF dei LNF, dal alla BTF dei LNF, dal 18 al 22 luglio, in modalità 18 al 22 luglio, in modalità “parassita” alle normali “parassita” alle normali operazioni per KLOE.operazioni per KLOE.

Setup

Vista YVista Y

00

11

22

33

44

55

66

77

88

99

1010

1111

1212

1313

Vista XVista X

H fingerH finger

V fingerV finger

Vista YVista Y

00

11

22

33

44

55

66

77

88

99

1010

1111

1212

1313

Vista XVista X

H fingerH finger

V fingerV finger

• VME DAQVME DAQ

• Charge integrating ADC, Charge integrating ADC, gate=200 nsgate=200 ns

• trigger dal sistema di timing del fasciotrigger dal sistema di timing del fascio

Fascio ottimizzato: Fascio ottimizzato: xx yy 2 mm2 mm

Bassa intensità:Bassa intensità: <n>=0.5 <n>=0.5 ÷÷11

Inefficienza (preliminare !)

SogliaSoglia

Inef

fici

enza

Inef

fici

enza

EEtotaletotale

11000 eventi con tag11000 eventi con tag

TuttiTuttiCon tagCon tag

70 140 210 280 350 (MeV)(ADC)(ADC)

Eve

nti

Eve

nti

CAVEATCAVEAT

• Prototipo realizzato nel Prototipo realizzato nel 1992, e strumentato su 1992, e strumentato su un solo latoun solo lato

• Qualche canale mostra Qualche canale mostra un un guadagno più bassoguadagno più basso (accoppiamento ottico (accoppiamento ottico guida/fotomoltiplicatore?)guida/fotomoltiplicatore?)

• I canali I canali non erano non erano equalizzati né calibratiequalizzati né calibrati (run di cosmici in corso…)(run di cosmici in corso…)

• La Statistica é limitata …La Statistica é limitata … e l’analisi é ancora in corsoe l’analisi é ancora in corso

Piano di lavoro 2006Test alla BTF con elettroni e fotoni (quando disponibili):• Misura dell’inefficienza in funzione di

– Energia

– Posizione/angolo di impatto (studio degli effetti di bordo)

• Misura della risoluzione temporale• Misura della risoluzione in energia• Studio dei segnali

– Ottimizzazione dell’elettronica di readout

– Ottimizzazione del guadagno

In particolare, vorremmo poter confrontare i risultati ottenuti In particolare, vorremmo poter confrontare i risultati ottenuti sul prototipo “CKM” e “Protvino” con quelli avuti su un sul prototipo “CKM” e “Protvino” con quelli avuti su un prototipo “a la KLOE” da costruireprototipo “a la KLOE” da costruire.

… … in modo che, entro il 2006 si possa giungere alla in modo che, entro il 2006 si possa giungere alla scelta della tecnologiascelta della tecnologia

Premessa: Il Gigatracker consta di 2 stazioni di

Pixel posizionate nella regione del secondo achromat, dove il fascio viene deviato di -40mm in direzione verticale e riportato in posizione dopo circa 6 metri.

Le due stazioni di pixel dovranno misurare la posizione e il tempo di passaggio delle particelle del fascio. Dalla seconda stazione e da una terza, equipaggiata con una FastTPC (KABES), ci si attende la misura della direzione di tali particelle, minimizzando la deviazione dovuta al multiple scattering.

R/O chipR/O chip SensoreSensore

BumpBumpbondingbonding

FE-TOFE-TO(CERN)(CERN)

La dimensione del fascio alle stazioni di pixel e' di circa 36x48mm2, con un rate massimo di 1.9MHz/mm2, 0.6MHz/mm2 in media, e in totale circa 1 GHz, di cui solo circa il 6% sono K+.

Dal decadimento del K+ inbar non si avra' alcuna informazione sulla posizione del vertice di decadimento (solo il + viene rivelato).

Le informazioni dal Gigatracker dovranno permettere la coincidenza di un + visto nel rivelatore (tempo dal hodo e direzione e momento dallo spettrometro) con un K+ passato nel GT.

Questo impone ai pixel risoluzioni, sia spaziali che temporali, piuttosto stringenti, tali da avere, sulla traccia:

t ~ 150ps, p/p <0.4%, ~17rad

mantenendo minimo il materiale posto su fascio (X0<<1%).

Caratteristiche

- Ottimizzazione spessore: 300m Si: 100 (chip) + 200 (rivelatore) 150 (chip) + 150 (rivelatore) supporto segnale! Da testare: segnale, fragilita', danneggiamento da radiazione (~12 Mrad in 100 gg)

fasciorate ~1GHzmaggior parte, solo 6.5%

12.32m

Pixel 1

6.05mKabes

final collimator,decay volume,detector

87m Ch1

40mm

80.681m from T0

86.731m from T0

Pixel2 99.051 m from T0

204.850mfrom T0

≈≈35000 canali/stazione35000 canali/stazione

- Ottimizzazione dimensioni pixel

X= 200 (300) m /√12 ->

X= 58 (87) m,

MultSc Si spessore 200m~13rad xMSP1= 13*6.05 ~80m

V pixel size mom resol (P1,P2) ( X√2 & xMSP1 )/40mm 200m (300) = 0.3% (0.4%) H pixel size Angular resol(P2,K3 kab=80m) (sX &skab ) /12.3m &MSP1

200m (300) = 15rad (16rad)

Per la realizzazione dell'elettronica di lettura dei rivelatori a pixel si stanno studiando due opzioni tecnologiche:

la CMOS 0.25 m e la CMOS 0.13 m.

La tecnologia 0.25 m è ben conosciuta e caratterizzata nei suoi aspetti di prestazioni analogiche e di radiation tolerance ed i costi sono relativamente contenuti.

Di contro le prestazioni che offre sono nettamente inferiori e queste potrebbero non essere sufficienti per l'esperimento.

Inoltre il supporto e l'aggiornamento del design kit per il progetto di circuiti tolleranti alle radiazioni si e` inoltre interrotto nel 2002.

La 0.13 m è attualmente in fase di caratterizzazione per quanto riguarda sia le prestazioni analogiche che la tolleranza alle

radiazioni. Trattandosi poi di una tecnologia di punta i costi saranno

superiori di un fattore ~2 rispetto alla 0.25 mm (2 M€ invece di 1 M€…)

R/O chip

E per il sensore, da dove si parte?

Esperienza: Alice SPD Sensore Si: CANBERRA

high resistivity FZ p+ pixel su substrato n spessore 200m pixel size 50mx425m

r/o chip CMOS 250nm spessore Si “supporto” 150m (nativo 750m)

bump bonding: SnPb VTT Finlandia best of the best yield ≥ 99%

Le richieste di P326 sul sensore al Si sono:

spessore 200m (min X0)

pixel dim 300m x 300m OK

(risoluzione su P e )

ConvenzioneINFN-ITC/IRSTcfr delibere 8610,8649Lavorazione gratuita: solo spese materiale es maschere, sensori

Non solo business...anche ricerca e su varisubstrati (n,p-type) di varia produzione (epi, FZ, CZ...)cfr es Boscardin @ Scuola LNL 4-8/04/2005

Test produzione & lavorazionebb VTT al chip di Alice conaggiunta strutture test ad hocVincoli: layout chip Alice

Dove siamo?3 wafer (200m-ex300A/B, 200ex600B) sent @ VTT

for bb with Alice's chip

--> expected back at CERN soon

Alice's standard test on the Ladder

Diodes and pixel arrays: tests and dicing

---> Legnaro for

irradiation studies with protons (bulk damage)

- measure Vfd, I

leak vs fluence and

- find equivalent fluence inversion point

- monitoring vs time and temperature

p+ n

n+

Example of n-type inversion on 300m thicktest structures for Alice, R.Wundstorfs thesis

69

Toward the working point in P326...-

eq inversion point and V

bias --> replacement every xxx days?

- cooling (e.g. ATLAS, CMS ~ -8°C : Ileak

)

Programma 2006:

Sensor: Test on

- Alice-like ladders and singles bb at VTT

- diodes & structures dicing

--> Legnaro, monitoring

Investigation on wafer bow: causes and

how to reduce it

Cooling:investigation just started

Chip:R&D ongoing

simulation & design

first hints if 0.25m not possible

expected by January06

(dimensions, consumption...)

If OK --> 2006 build and test

a chip with the various

functional blocks and

architecture options

70