Transcript LHCf Status Report CSN1 September 2007

LHCf Status Report
Measurement of Photons and Neutral Pions in the Very
Forward Region of LHC
Frascati, CSN1, 18 Settembre 2007
Oscar Adriani
INFN Sezione di Firenze - Dipartimento di Fisica dell’Università degli Studi di Firenze
Development of atmospheric showers
Cosmic ray spectrum
Tevatron
LHC
A 100 PeV fixed-target interaction
with air has the cm energy of a pp
collision at the LHC
AUGER
Correct simulation of interactions of
primary cosmic rays with the
atmosphere is essential to cosmic ray
studies
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
The dominant contribution
to the energy flux is in the
very forward region ( 0)
In this forward region the
highest energy available
measurements of p0 cross
section were done by UA7
(E=1014 eV, y= 5÷7)
LHCf detectors will allow to
understand and model pp,
(pA, A’A) interactions
giving rise to air-showers in
the 1017-18 eV range.
Oscar Adriani
LHCf location
Detector I
Tungsten
Scintillator
Scintillating fibers
Detector II
Tungsten
Scintillator
Silicon mstrips
INTERACTION POINT
IP1 (ATLAS)
140 m
Beam line
140 m
Detectors will be installed in the TAN
region, 140 m away from the Interaction
Point 1, in front of luminosity monitors
Here the beam pipe splits in 2
separate tubes.
Charged particles are swept away
by magnets!!!
We will cover up to y
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
We use LHC style
electronics and readout
Detector # 2
4 pairs of silicon microstrip layers
(6, 10, 30, 42 r.l.) for tracking purpose
(X and Y)  impact point
2 towers 24 cm long stacked on
their edges and offset from one
another
Lower:2.5 cm x 2.5 cm
Upper: 3.2 cm x 3.2 cm
 < 400 mrad
16 scintillator layers
(3 mm thick)
Trigger and energy
profile measurements
Energy
Frascati, 18 Settembre 2007 - CSN1
Absorber
22 tungsten layers 7mm thick 
44 X0 (1.6 lI) in total
(W: X0 = 3.5mm, RM = 9mm)
LHCf Status Report
Oscar Adriani
Performances of the LHCf Detector
Measured at the SPS
Beam Test in 2004
SciFi Position Resolution
Energy Resolution
LHCf can measure (and provide to
LHC) the center of neutral flux
from the collisions
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
If the center of the
neutral flux hits LHCf
 << 1 mm resolution
Oscar Adriani
p0 mass resolution
2 g identified in the 2 towers
Arm #1
DE/E=5%
200 mm spatial resolution
Dm/m = 5%
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Monte Carlo g ray energy spectrum
(5% Energy resolution is taken into account)
106 generated LHC interactions 
1 minute exposure @1029 cm-2s-1 luminosity
Discrimination between various models is
feasible
Quantitative
discrimination
with the help of a
properly defined c2
discriminating
variable based on
the spectrum shape
(see TDR for
details)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Model dependence of neutron energy distribution
Original n energy
Frascati, 18 Settembre 2007 - CSN1
30% energy resolution
LHCf Status Report
Oscar Adriani
Both detectors are
ready since April
2007
Front Counter
(Both for Arm1&2)
read by a MAPMT
R7600U-00-M4
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Readout electronics
LHC style electronics
(Many thanks to CMS!!!!)
DOH
CCU
PLL
DCU
…
PACE3 chips (CMS preshower)
100
Mbit
Optical
Link
We have developed
•Hybrid circuit (Left+Right)
•Mother Board (Logic)
•Adc Piggy Back board
DAQ:
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
100 Mbit/s optical link
VME Readout
Oscar Adriani
Final electronics for Arm2
Power Board
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Mother Board +
ADC boards
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
The readout boards in the electronics box
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Now the real installation in LHC…
The idea is that installation takes place in 2 steps:
Pre-installation
Final installation
In between the 2 installation the baking out of the beam
pipe will be done (200 oC), so the detectors should be
removed
Pre-Installation dates have been fixed in Fall 2006
– LSS1L (Arm1)
o 8/01/2007 to 26/01/2007  FINISHED!
– LSS1R (Arm2)
o 23/04/2007 to 11/05/2007  FINISHED
The dates for the final installation are still under discussion
(Decision in Fall 2007)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Arm1 pre-installation
Transport and
insertion in the TAN
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Arm2 pre-installation
Explicit request from TS/LEA: Speed
up the cabling connection time!
Some work is in progress for this
(Splitter box, Distribution board)
A ‘second pre-installation’
is foreseen in Autumn
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Readout and control scheme for Arm2 Silicon
~ 240 m
USA15
TAN
Arm2
VME Crate
Multimode Optical Fibers
Monomode Optical Fibers
DOH
MB + ADC
Control PC
Thermistors
TSC+FEC
Power
Signal +
Control
Thermistors
Power Supply
High Voltage
High Current Cables
Sense wires
Splitter
Box
Distribution
Board
High Voltage
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
General LHCf DAQ scheme
Frascati, 18 Settembre 2007 - CSN1
LHCf Rack Allocation
in USA15
LHCf Status Report
Oscar Adriani
What do we have to do? (Slide of June 2007)
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Final commissioning of the electronics (modifications to the
logic, complete the PCBs, distribution board etc.) Done
Installation of the new splitter box in the tunnel  Done
Some work in USA15 and TAN region to speed up the
interconnection time  Partly done
Final DAQ software common with Japan people  Well started
Monitoring program
Test beam with final apparatus (August 24, September 11)
 Next
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part of the talk will focus on this item
Second pre-installation to test the modifications done after the
first pre-installation
Final installation: schedule is under discussion (December?
January 2008?)  Surely in 2008
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
2007 Test Beam
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 3 weeks of Beam Test (24/08 – 11/09)
SPS H4
Main Objectives:
– Absolute energy calibration of Arm1 & Arm2 by
using electrons with as many energy points as
possible (50 GeV – 250 GeV)
– Measurement of spatial resolution for Arm2
– Energy resolution for protons
– Direct identification of p0 produced in light target
– Test with detectors in final configuration (Power
supply, DAQ, Control system etc.)
Agilent Low Voltage Power Supply……… 
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
The experimental setup behind GOLIATH magnet
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Arm2
Adamo tracking system
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Beam test: some general points…
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11 days Arm2, 8 days Arm1
> 106 events for Arm2
Electrons:
Hadrons:
Muons:
50 GeV
100 GeV
150 GeV
200 GeV
200 GeV
350 GeV
200 GeV
Common DAQ, between Silicon and Scintillator part
– MIDAS based DAQ system (starting point for the final DAQ system)
– DAQ rate was limited to 30 Hz by Adamo tracking system
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Trigger from calorimeter towers has been tested
Dedicated study to optimize the PACE3 working condition (to
increase the dynamic range)
TDC was used to correct for the asynchrony between particles
and 40 MHz clock
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Possible study of direct p0 detection?
Following the referee suggestion we tried to
directly identify the p0 produced by proton
interaction in a light target
g
350 GeV Proton beam
Not in scale!
g
Carbon target
(3 cm)
in the slot used for beam monitor
9.15 m
Arm1
>107 proton on target (special setting from the SPS people)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
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Dedicated trigger on both towers of the
calorimeter has been used
Main problems:
– low photon energy (≥ 20 GeV)
– Direct protons in the towers
– Multi hits in the same tower
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 200 p0 events should be triggered (in a quite
big background) Challenging!!!
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Expected results for 35.106 proton on target
Simulated invariant mass
No cuts and efficiencies
applied
Expected invariant mass
by using estimated efficiencies
and standard cuts
Arm1
280 events
Frascati, 18 Settembre 2007 - CSN1
Arm2
540 events
LHCf Status Report
Oscar Adriani
p0 Like Event
Calorimeters
Shower Profile @ First SciFi Layer
40mm
Egamma=18GeV
X
Y
20mm
Egamma=46GeV
X
Y
~ 250 p0 events acquired on disk
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Here few plots of the PRELIMINARY
results…….
… The test is finished last Tuesday….
All results are preliminary
NO TDC correction!
Only silicon info is considered
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
PACE3 pedestals and sigma
Pedestal
X view
Sigma
y view
Nominal Pace3 parameters … Not so good…
1
2
3
4
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
PACE3 sigma after parameters tuning
Low Gain
Frascati, 18 Settembre 2007 - CSN1
High Gain
LHCf Status Report
Oscar Adriani
Pedestal for various PACE3 parameters
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
50 GeV e-
Frascati, 18 Settembre 2007 - CSN1
200 GeV e-
LHCf Status Report
Oscar Adriani
100 GeV e-
Frascati, 18 Settembre 2007 - CSN1
200 GeV e-
LHCf Status Report
Oscar Adriani
m 200 GeV
Frascati, 18 Settembre 2007 - CSN1
Hadron 200 GeV
LHCf Status Report
Oscar Adriani
200 GeV e-: Many superimposed events
Low Gain
High Gain
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Energy correlation on the x-y layers
Low Gain
High Gain
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Total measured energy in silicon
50 GeV
100 GeV
200 GeV
150 GeV
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Spatial resolution
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ADAMO tracking system is used to track particles
towards ARM2
~ few mm spatial resolution for ADAMO
The expected impact point on the ARM2 silicon planes
is evaluated
Peak search is performed on the ARM2 silicon data
Lorentzian fit to reconstruct the impact point on
ARM2
Difference between ADAMO extrapolated point and
ARM2 reconstructed point is used as estimator of the
ARM2 spatial resolution
Very preliminary results!
– No optimal impact point reconstruction
– No relative alignment between ADAMO and ARM2
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Spatial resolution for 200 GeV electron
Y projection
s~ 75 mm
YAdamo – YArm2
XAdamo – XArm2
X projection
s ~ 50 mm
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Spatial resolution vs Electron energy
X spatial resolution (microns)
Resolution (microns)
120
No alignment!!!!
100
80
60
40
Preliminary
20
0
0
50
100
150
200
250
Electron Energy (GeV)
Y spatial resolution (microns)
Resolution (microns)
160
140
No alignment!!!!
120
100
80
60
40
Preliminary
20
0
0
50
100
150
200
250
Electron Energy (GeV)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
LHCf proposed running scenario
 Phase-I
 Run since the very beginning of LHC operations (Stage 1, 43
bunches)
 Remove the detector for radiation issues when the luminosity
reaches 1031cm-2s-1
 Phase-II
 Re-install the detector at the next opportunity of low
luminosity run (Totem dedicated runs? Possible LHCf
dedicated runs?)
 Phase-III
 Future extension for p-A, A-A run with upgraded detectors?
We are continously in touch with Machine and ATLAS peoples
to agree on detailed running and installation scenario
We had a dedicated Meeting with Atlas Management
(Peter Jenn, Per Grafstrom, Marzio Nessi, ZDC groups etc.)
at beginning of September
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
From Helmut Burkhardt
LHCf Optimal Running Conditions
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Summary
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Detectors are ready
Pre-Installation completed
Very long test beam finished
Second pre-installation this year
Final installation next year
Waiting for LHC Beam!!!!!
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Back up Slides
Milestones dei preventivi 2008
– 01-05-2008
Installazione definitiva di Arm1 e Arm2 (se compatibile con
la macchina)
– 01-08-2008
Inizio presa dati (compatibilmente con il funzionamento
della macchina)
– 31-12-2008 (Milestone aggiuntiva)
Risultati preliminari da calibrazione/allineamento
(compatibilmente con il funzionamento della macchina)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Detector #1
2 towers ~24 cm long
stacked vertically with 5
mm gap
Lower:2 cm x 2 cm area
Impact point (h)
4 pairs of scintillating fiber
layers for tracking purpose
(6, 10, 30, 42 r.l.)
Upper: 4 cm x 4 cm area
Absorber
22 tungsten layers 7mm thick 
44 X0 (1.6 lI) in total
(W: X0 = 3.5mm, RM = 9mm)
q < 300 mrad
16 scintillator layers (3
mm thick)
Energy
Trigger and energy
profile measurements
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Energy spectrum of π0 expected from different models
(Typical energy resolution of g is 3 % at 1TeV)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Clear CR signal separation
(20ADC by 2249W ~ 5pC)
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
Installation of the detectors in the TAN absorbers at 140m
from IP1
LHCf
96 mm
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
The LHCf operation in LHC
Optimal LHCf run conditions
Beam parameter
Value
Beam parameters used for
commissioning are good for
LHCf!!!
# of bunches
≤ 43
Bunch separation
> 2 msec
Crossing angle
0 rad
140 mrad downward
Luminosity per
bunch
< 2 x 1028 cm-2s-1
Luminosity
≤ ~1030 cm-2s-1
Bunch intensity
4x1010 ppb (b*=18 m)
1x1010 ppb (b*= 1 m)
No radiation problem for 10kGy by a “year” operation with this luminosity
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani
From R. Bailey presentation at January 2007 TAN workshop
Optimal conditions for LHCf running!
Stage 1
Frascati, 18 Settembre 2007 - CSN1
LHCf Status Report
Oscar Adriani