Roma 16 maggio 2006 Commissione I Detector status Pisa commitments Analysis Laboratory tests TileCal Status report (ATLAS-Pisa)

Roma 16 maggio 2006 Commissione I

•Detector status•Pisa commitments

•Analysis•Laboratory tests

TileCal Status report (ATLAS-Pisa)


TileCal installation

• Barrel installed (end Oct. 2005) and instrumented, commissioning in progress.

• EBC installed, in place (1 Feb. 2006), being instrumented, gap scintillator installed.

• EBA being installed, Lar cylinder in place, will be ready for commissioning end May.


Barrel (1)• Barrel is cabled

• All the FE electronics has been mounted and is working

• DAQ is moving smoothly from the portable (MOBIDAQ) to the final one (RODs)

• First Cosmic Ray data has been taken with MDT using a limited azimuthal region (power supply/cooling problem)


An event MDT/Tile


Barrel (2)

Still some problems are delaying the barrel commissioning:

– Cooling pipes just arrived – LVPS have been fixed but However the system has not

been extensively tested. We are aware that other faults could show up.

– HV trips on drawers (7% of drawers have occasional trips) have been understood (humidity+dust), a working solution has been proposed (slowly blow dry air). Still investigating the origin of the problem.


EBC almost in place


EBC + EBA

• EBC installation completed (1/2/06) – Geometry within tolerances.– Commissioning is proceeding (control and trigger

cables, piping…)– Moved “near” the Barrel. Tile/Lar relative position are

off by 12mm in z wrt nominal. Impact on B-field have been analysed. Decision was made to position EBC as near to barrel as possible. EBA in nominal position

– EBA is being assembled in the pit. On schedule, expected ready by end May 2006.


EBC being completed


EBC almost in place


EBA being installed


Pisa responsibilities

We are well represented in all this activities.

Iacopo Vivarelli online tools (tests on commiss.)

Chiara Roda co-convener of JetEtMiss group

Anna Lupi TileCal software

Andrea Dotti online monitoring (presenter)

Nino Del Prete TileCal IB chair


Activities at CERN (2006)

1. trigger cabling LB (July-August) (techs)2. Test all LB (LVPS, HV tests, FE) (Jan-Dec) (Iacopo,

Francesca, Maria)3. Barrel timing with laser (Sept./Nov) (Iacopo, Paolo)4. DAQ/Monitor (Aug./Dec). (Chiara, Andrea)5. Cosmics Run (standalone, with MDT and/or Lar) fall 2006

(all)6. Installation/commisioning EBC, EBA (The same amount

of work as for LB) (know how from LB)


Other activities in Pisa

Physics studies: VBF Higgs : Hbar

Jet calibration

Comparison G4/CTB

Low energy pions in CTB

Laboratory measurements: (PMT/Fibres) synergy with the

Computer Science Dpt of Univ Pisa


hET miss

HVBF(120 GeV) hh

fbhhBRHBRVBFsig 125)()( BR (tau hadrons) : 65% ; BR(hh) : 42.25

%

VBF H = 300 fb

Signal signature :- 2 high pt forward jets , - 2 central tau jet ,- ET

miss

4 jets & ETmiss

Backgrounds: QCD (~9 mb), Z/*+jets (1700 pb) , ttbar (550 pb)Crucial the tau identification: collaboration with Milano, Freiburg, Toronto

V.Cavasinni, F.Sarri, I. Vivarelli


Cut Signalefficienc

yEvents

QCDefficienc

yEvents

Z+jetsefficienc

yEvents

Ttbarefficienc

yEvents

4jet (2 tau), Et

miss > 45 GeV

4.4% 3.4 10-8 4.6 10-3 7.3 10-4

Pt tau (45,35)

1.14% 2.3 10-11 5.8 10-4 1.1 10-4

Pt forward (60,40)

0.72% 7.4 10-12 2.2 10-4 6.8 10-5

forward 0.37% 4.7 10-13 1.3 10-5 2.4 10-6

Cuts 0.25% 7.5 10-14 5.8 10-6 0.5 10-6

Mjj (700 GeV) 0.22% 5.8 10-14 5.0 10-6 4 10-7

Jet veto (30 GeV)

0.2% 7.3

3.2 10-14 9

3.2 10-6

671.7 10-7

4.4

Mass window 0.15%

61.7 10-15

0.55 1.6 10-7

3.3 0

SUMMARY ATLFAST 30 fb-1

In p

rogr

ess

Validation with full simulation started


Jet calibration

The H1 method : jet energy is the sum of weighted cell energy.

QCD 2 jets events has been used to compute weights using “topoclusters” and cone algorithm (R=0.7).

The method/weights prooved to be good also for calibrating jets with different cones (R=0.4) and different samples (t-tbar) and seems to work well also for CTB data.

This algorithm is robust and stable and is implemented in ATHENA.


Similar good results using the same weghts obtained witha Cone0.4, ttbar events, and CTB data


Very Low Energy CTB

CTB has collected data at low energy (3-9 Gev/c)

• It is important to measure the calorimeters response to a low energy pion (a jet = many low energy pions)

• It is difficult for many experimental problems:

• particle identification (e, pion, mu)

• the beam has a parasitic high energy muon component

• energy calibration is still not properly understood

The work is still in progress.

(M. Canneri, V. Cavasinni, F. Sarri, I. Vivarelli)


CTB set up for VLE

Our aim: obtain the purest pion sample from VLE data.The VLE beam is made of electrons, pions and muons

(μ at the same η of the run and off axis).Electrons are easy to separate.

ALL sub-detector are exploited for the muon selection

Muon tag BC-2

Sec. targetDipole magnets CHRV2, LE

VLE particles

HE muons

BC-1 BC1 BC2

Beam stopBC0

Quadrupole magnets

ID

Muon wall

LAr Tile

Cryostat scint.

Muon Halo

S1 S2/3

MDT/RPC


LE Muon identification in TileCal (likelihood)

)()()( 332211 EPEPEPL (Pi(E) energy distr. in Tile layer i)

MC DATA

PionsPions

The shape of L allows a rejection of muons.MC do not quite reproduce data (more later).


Energy ε for μ off axis ε for μ by likelihood μ-contamination e-contamination

(GeV) (%) (%) |likelihood|<30 (%) [μ (1-εmu lik)] /π (%) /π 9 92.4 ± 0.6 89.7 ± 1.0 15.0 0.6

7 85.8 ± 0.8 99.3 ± 0.1 2.7 0

5 94.0 ± 0.7 99.48 ± 0.07 10.2 0.3

3 83.6 ± 2.2 99.83 ± 0.03 11.1 0.6

Efficiencies and contamination

Electrons are easily identified by beam Cerenkov.Muons can be identified using L or by MDT etc.

In p

rogr

ess


A CTB “TAU jet”

• 3 pion of 7 GeV superimposed in LaR TILE


Test beam data, Energy deposit: G4 vs EXP, muons (1), the em scale

(V.Kazanine)

MOP value EXP: 3340±60 MC : 3399±6

Energy deposition in the calorimeters (log and lin scales)

Lar+Tile Lar+Tile


Energy deposit: G4 vs EXP, pions (1)

• All cells in TileCal are used while in LAr only the cells within ±0.2 eta and ±0.2 phi LAr window (eta = 0.25, phi = 0) are used;• The cut on the energy at cells is Ecell > 2 sigma noise;• Energy deposition in the calorimeter is the sum over selected cells;• The energy deposition at Cryo is approximated as :

1 . 47 ETileA E BackLArTotal energy deposit. The correction on energy deposition at Cryo is included.

Lar+Tile


Francesca Sarri, Giulio Usai

PMTs STABILITYPMTs STABILITY

We have measured in our lab the gain, QE, noise etc of 24 PMT (the same used in TileCal), illuminated with continuous light simulating LHC at L=1034 cm-2s-

1.

Led light yield monitored by two photodiodes.

Surprisingly the gain of all PMT increased with time at a rate of about 0.5-0.7 % per month.

No instrumental effect was found. Moreover the precise Cs calibration in different CTB periods confirms the effect also quantitatively


Almost 14 months(April05-May06)

Vnom:= Gain(Vnom) = 105

Gain(V) ~ V

Light source changed, because of LED and LED driver broken at the end of Jan’06.

Status up to 2006

Labo:

Vn/Vn = -.41±0.13 (3mnts estimate) (measured untill Jan’06)

Cs Calibration (at theCTB):

Vn/Vn = -.36±0.04 (3mnts)


Summary: NOV’05-JAN’06

Average slope of 15 PMTs, NomVol drop estimate in 3 months

Average slope of 15 PMTs, PMT/PHD rise estimate in 3 months.

mean : - 0.36 % rms : 0.22 %

mean : 1.6 % rms : 0.8 %

NomVol drop (%) PMT/PhD (%)


The curved fibre ageing

50 cm

N. Del Prete, Francesca Sarri


Fibre ageing

Step motor

Shutter

PMT

At each step, the PMT current is measured.Then the wheel is positioned in the different locations for more precise measurements.

The precision in the ratio Fibra1/Fibra2 is about 6 10-4 sistematics under study


Backup slides


Monitor and Presenter

•Presentations on the progress of the monitoring working group presented at CHEP06 by A.Dotti and W.Vandelli.


RPC

We use the RPC in order to try to understand the fake by MDT on electronevents (many events have more than 13 hits in MDT).They could be muons that are outside Tile calorimeter acceptance.

RPC


RPC geometry

Zone of inefficiency for muons by Tile

Only the bottom halfof the RPC (negative y)is working in the runs


Pions : sADC_Cherenkov2<620 && N hits in TRT <4 && not μ(mouns: signal in MDT or MuonWall or MuonTag)E Tile in the cone 0.19< η <0.61, all φ; E Lar in the cone 0.19 < η <0.61, -0.1< φ < 0.1

Energy Distributions for pions

Pions at 9 GeV


red : full AODs, black fast AODs.

In progress:-Validate ATLFAST with full simulation-New parametrization for tau-ID (with the Toronto Group)

QCD SIGNAL


Same weights applied also to the ttbar events, Rome sample


The same weights (determined in QCD MC events) work well for different cone definitions, for different samples and also

(preliminary) on Combined Test Beam data. This method seems more robust than the “standard” ATLAS jet calibration


First steps on CTB comparison: G4 vs EXP

Vassili Kazanine (Budker Institute Novosibirsk, a former (and future) FAI in Pisa)

The simulation of calorimeters in G4 has been the subject of previous studies (Anna, Andrea) using TileCal standalone (TB vs G4).Now G4 simulation of CTB is available and Vassili has taken up the issue of comparing data and MC.

The energy scale seems to be under control and the total energy deposition in Tile+Lar is well reproduced, but: • the energy in Lar is predicted too large and in tile too small• once more we have the problem of the longitudinal shower shape not correctly predicted by G4.


Richieste: ME

Stato delle spese ad oggi:

ME: assegnato 109 k€ speso ad oggi 55K€ (51%)manca ancora il contributo tecnici per commissioning (7 mu)

E’ richiesta la presenza continua al CERN di Vivarelli e Dotti. Questo non e’ compatibile col finanziamento attuale.

Abbiamo richiesto una integrazione di 6 mu per arrivare a fine anno.


DAQ A new, friendly, DAQ system was built using a CAEN Brigde (V1792) which interface VME to a PC where the DAQ system runs through ROOT.

A student (Marco Raglianti) from the Computer Science Department has designed this nice and simple system as part of his “tesi di tirocinio”.

The Bridge has become a powerful development system. C++ programs can be fully tested, in ROOT, and then compiled and run on single board PC in VME.

What is missing are VME units (ADC etc.): we use old CAMAC units that we have interfaced to VME. Often these units are faulty...


Preliminary.The precision of the method is OK. The problem is

the mechanical stability (LED position, optical couplings etc.).

Time (h)

10-3

rms = 6 10-4

Documents

Roma 16 maggio 2006 Commissione I Detector status Pisa commitments Analysis Laboratory tests TileCal Status report (ATLAS-Pisa)