Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

ATLAS Roman Potsstatus, commissioning and operation

Beniamino Di Girolamoon behalf of the ATLAS Luminosity WG

CERN

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

ATLAS Roman Pots locations

RP

240m

240m

RPRP RP

RP RP RP RP

IP

CERN

LHC

SPSATLAS

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Roman Pot

LHC Beam

ATLAS Roman Pot Unit

Shielding

Fiber Connectors

20 x 64 Fibers (Tracker)

Overlap FiberDetector

Roman Pot

Vacuum Flange

Front-End Elec.

24 MAPMTs

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Scintillating Fibre Tracker

LHC b

eam

• 64 scintillating fibers• 0.5 mm2 square

planes are horizontally staggered by multiples of 70.7 m.

~ 3 x 3 cm2

Concept

• 2 x 10 U planes • 2 x 10 V planes

Ceramic Substrate

Positioning plate

Fiber Connector

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

DESY Testbeam - November 2005

Trig.

Trig.

Si1

Si2Si4

S1 x S2

S3

Detectors

A set of different detectors was built to test: Light yield, Efficiency, Cross talk, Edge sensitivity, Resolution etc.

Base line fiber: (SCSF-78, S-type)Kuraray 0.5mm2 single cladded

Beam

• 6 GeV electrons• Beam spot ~ 1 cm2

Setup

• Si telescope (~30 m resolution)• MAPMT – CAEN QDCs – PC

2x10x6 Detector

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

DESY Testbeam published results

Light yield:4.5 p.e.Efficiency ~ 95%

Non-Active Edge Region << 100m

# E

vents

# E

vents

S330

ALFA(2x2x32)

ALFA Resolution:x,y ~ 36 m

Potentially increased by multiple scattering of the relatively low energy electrons

Si-Tel.ALFA + Si-Tel.

Y (m)

Signal (ADC counts) Residual (m)

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Final front-end electronics

MAROC R/O chip(64 x Amp. + Disc.)

R/O FPGA

Adaptor Board

HV BoardMAPMT

PMF(PM Front-End)

TriggerRead-Out

MotherBoard

(PMFs + MAPMTs)

Trigger

Read Out System

40 m

m

30 mm

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

CERN Testbeam - October 2006

2x2x64 + Final Trig. Overlap Detectors

2x10x16Beam

• 230 GeV protons ()

Setup

• 5 x MAPMT – 5 x PMF - Motherboard – PC

Detectors

• Two ALFA trackers (larger wrt DESY TB)• Overlap Detectors

PMFs

MotherBoard

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

CERN Testbeam very preliminary results

“Online” Results !

Offline analysis on going

ALFA Event

ALFA Active Area

(Reconstructed using 2 x half of ALFA)

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Final ATLAS RP Unit

Derived from TOTEM design

Changeso No horizontal poto Different mounting of

Pot on flangeso Modified base and

fixes to respect beam height and to allow easier extraction of bottom Pot

Designer: J-M Lacroix (TS)

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Mechanics status

Received pre-series Roman Pot Unit at CERNo Being assembled and soon tested by PH/DT1 teamo Will be a fully operational Roman Pot Unit

• Will be also used to setup the control system and to organize the cable routing and patch panels

o Need of commissioning the movement precision• Verification of possible deformations under vacuum• Assessment of the achievable precision and

reproducibility

o Foreseen use in 2007 testbeam setup We will start the final procurement after pre-series

sign-offo 4 Roman Pot Unitso Order: February-March 2007

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Posit

ion

ing

: to

day a

nd

to

morr

ow

Today “Tomorrow”

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

The two RP Units on one side

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Overlap extrusions brazed on bottom

Top flange

Pumping hole

Rectangular body out of centerBrazing under test S.Mathot (TS-MME)

Final Pot

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Final Pot: extrusions for Overlap detectors

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Top view of the detector in the pot

Fiber detectorTrigger scintillator (detector)

Overlap detectorTrigger scintillator (overlaps)

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Scheduling Roman Pot Units

o 4 Units to be procured• After sign off on pre-series

o Procurement of motors, screws, rails and misc.• Started

o Currently foreseen delivery: Spring-Summer 2007• Installation in May 2007 seems difficult, not yet impossible

– We would only install the mechanics with either pots or covers in the main vacuum chamber. No movements, all blocked in safe position.

• Otherwise waiting for next shutdown (2007/08) Pot

o First prototype being prepared• Will be tested under vacuum• One or two will be used for the future test beam

o Simulation of RF compatibility ongoing and tests to be done

o Final production in sync with Roman Pot Units production• All material procured

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Scheduling

Cables in place, ancillary elements being procuredo Patch panels being preparedo Movable vacuum equipment to be

procured Detector and electronics

o Concepts proved to be suitable for our application• We are improving various details and we plan a

testbeam in 2007

o Aiming for installation by shutdown 2008/09

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Commissioning (shutdown 2008/09)

Commissioning during shutdowno Movements and controlso Access procedureso Safety procedureso Vacuum systemo Interlockso Simulation of normal and alarm conditions

Joint LHC Machine-Experiments Workshop on Very Forward Detectors - 25 January 2007Beniamino Di Girolamo - CERN PH

Operations (2009 run)

If luminosity would allow with nominal opticso In park position

• Detector commissioning with halo particles• Background studies

With high opticso Approach to the beamo Detector commissioning (1st time)o Test on overlap detectorso Normal running