27 Settembre 2011
SIF 2011 – L’Aquila, località Coppito
La sperimentazione al JLab
Evaristo Cisbani / ISS e INFN-Sanità
 Introduzione al Jefferson Laboratory e alla collaborazione
italiana
 Sperimentazione fisica
• Nucleon Structure (Form Factor and Quark Distribution)
• Parity Violation Experiments
• Meson Spectroscopy
 Strumentazione
• RICH/Clas12
• Photon Tagger
• HD Polarized Target
SIF 2011 / L'Aquila • GEM/SiD TrackersE. Cisbani / La Sperimentazione al JLab
1
• Newport News / Virginia / USA (3 ore da
Washington DC)
• Finanziamento DOE + Enti Locali (no MOF!)
• Direttore: H. E. Montgomery (ex associate
director for research al Fermilab)
• 2000 Utenti internazionali
SIF 2011 / L'Aquila
E. Cisbani / La Sperimentazione al JLab
Thomas Jefferson National Laboratory
• Ricerca fondamentale con acceleratore di
elettroni e 3+1 sale sperimentali
• Ricerca applicata con FEL ed altre facility
• Sito Web: www.jlab.org
2
Arc
SIF 2011 / L'Aquila
• Acceleratore lineare
ricircolante e- a cavità
superconduttrici
• Fascio polarizzato
• Alta corrente (200 mA)
• Energia massima 6 GeV
• 100% duty factor
• Rilascio del fascio
simultaneamente alle tre
sale sperimentali A, B e
C
Arc
E. Cisbani / La Sperimentazione al JLab
Acceleratore CEBAF oggi
Iniettore
A
B
C
3
Hall B/CLAS
Hall C
Two High Momentum
Resolution + one
large angular
acceptance
spectrometers
Dedicated neutron and
gamma detectors
Large acceptance
High multiplicity
reconstruction
Six coils Toroidal
field
Two Asymmetric
spectrometers
High momentum
range and high
resolution
Dedicated detectors
High beam currents
(>100 mA), lumi 1037
cm-2 s-1
Tagged real
photons beam
High beam currents
(>100 mA), lumi 1037
cm-2 s-1
3He
NH3/ND3 Polarized
long. target
NH3/ND3 Polarized long.
target, high flexibility
unpol. from H to Pb
Large and flexible
installations
4p coverage
Moderately large and
flexible installations
T/L Polarized
target, high flexibility
unpol. from H to Pb
E. Cisbani / La Sperimentazione al JLab
Hall A
SIF 2011 / L'Aquila
Sale sperimentali complementari, oggi
4
add Hall D
(and beam line)
6 GeV CEBAF (< 2013)
Max Current: 200 mA
Max Energy: 0.8 - 5.7 GeV
Long. Polarization: 75-85%
SIF 2011 / L'Aquila
Acceleratore CEBAF dal 2013
CHL-2
12 GeV CEBAF
(>2013)
Max Current: 90 mA
Max Energy Hall A,B,C: 10.9 GeV
Max Energy Hall D: 12 GeV
Long. Polarization: 75-85%
E. Cisbani / La Sperimentazione al JLab
Upgrade magnets
and power
supplies
5
Hall B/CLAS12
+ 1 large angular and
momentum, high
lumi spectrometer
with hadron ID
+ Dedicated
equipment
New beam line
New 4p toroid
detector with
(likely) extended
hadron ID
+ lumi 1038 cm-2 s-1
+ forward tagger for
real photons
+ higher targets
thickness
+ trans. polarized
H/D target
hallaweb.jlab.org
www.jlab.org/Hall-B
Hall C
+ “super high”
momentum
spectrometer
+ dedicated
equipment
Hall D/GLUEX
Excellent hermetic
coverage,
Solenoid field
High multiplicity
reconstruction
108 linearly
polarized, up to 12
GeV, real
photons/s
www.jlab.org/Hall-C
www.jlab.org/Hall-D
www.gluex.org
E. Cisbani / La Sperimentazione al JLab
Hall A
SIF 2011 / L'Aquila
Sale sperimentali dopo il 2014
6
• Origin of quark and gluon confinement (non-perturbative QCD) (B & D)
– Gluonic excitations - existence and properties of exotic mesons (and baryons)
SIF 2011 / L'Aquila
JLab physics investigations
– Mesons and baryons spectroscopy
• Dynamics of the quarks/gluons in the nucleons (A,B and C)
– New view of nucleon structure via the Generalized Parton Distributions (GPDs)
accessed in Exclusive Reactions
– Form Factors - improve knowledge of charge and current in the nucleons;
constraints on the GPDs
• Dynamics of the nucleons in the nuclei (A, B and C)
– The Quark Structure of Nuclei (resolving the EMC effect)
– The Short-Range Behavior of the N-N Interaction and its QCD Basis
– Quark propagation through Nuclear Matter (hadronization)
E. Cisbani / La Sperimentazione al JLab
– Parton Distributions Functions (and Fragmentation Functions)
• Standard model limits (A and C)
– High Precision Tests of the Standard Model via Parity-Violating Electron
Scattering Experiments
– Measure nuclear properties by weak interaction
7
SIF 2011 / L'Aquila
Esperimento INFN formalmente attivo
dal 2009 per 7 anni, nasce dalla
sinergia delle ex sigle AIACE + LEDA
sperimentali offerte
dall’aggiornamento a 12 GeV
Intensa attività sperimentale al JLab/6 GeV (prevalentemente in sala A e B)
Forte coinvolgimento negli sviluppi legati al raddoppio di energia del fascio e
aggiornamento degli apparati nelle sale sperimentali
E. Cisbani / La Sperimentazione al JLab
per sfruttare al meglio le opportunità
Sezioni INFN partecipanti (BA, CT, GE, FE, ISS, LNF, RM, RM2):
Ricercatori + Tecnologi: 50 (32.3 FTE)
Coordinatori Nazionali: P. Rossi (LNF), E. Cisbani (ISS-Roma)
8
Nucleon (Spin)
Structure
(semi inclusive deep inelastic scattering)
SIF 2011 / L'Aquila
E. Cisbani / La Sperimentazione al JLab
JLab12
9
Description of the nucleon at leading order
in terms of partons
U,L,T = Unpolarized, Longitudinally,
Transversely Polarized
(relative to a predefined direction)
If transverse momentum is
suppresed, only 3 DFs contributes
SIF 2011 / L'Aquila
E. Cisbani / La Sperimentazione al JLab
Origin of the nucleon spin / Nucleon structure
1
0
e’
(E’, k’)
(E, k)
SIF 2011 / L'Aquila
Probe the nucleon structure by SIDIS
e
X
FNAL
BNL J-PARC
E. Cisbani / La Sperimentazione al JLab
N
1
1
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
Peculiarity of JLab
From M.Contalbrigo
Access unexplored valence region (high Q2 requires high luminosity)
1
2
SIF 2011 / L'Aquila
Collins small, largely compatible to 0; Sivers negative (?) for p+, zero for p-
E. Cisbani / La Sperimentazione al JLab
First direct measurement on neutron
TMD’s latest results at JLab
1
3
From A. Puckett, Jlab 2011
Hall B
CLAS12
High luminosity
Hall A
SBS
E12-09-018: p+,pK+,K3He
H2,NH3,D2,ND2,HD-Ice
All experiments approved by JLab PAC August 2011 with high rating
SIF 2011 / L'Aquila
4p acceptance
E. Cisbani / La Sperimentazione al JLab
TMDs @12 GeV
All experiments have JLAB12 members as co-spokepersons
Very extensive and exhaustive program
Require new targets (HD) and new detectors (RICH, GEM)
Adapted from P. Rossi/CSN3-2011
1
4
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
The “ultimate” descriptions of the nucleon
1
5
Nucleon
Form Factors
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
JLab12
1
6
e + p → e’ + p’
SIF 2011 / L'Aquila
Proton Form Factors
d
 2
2
 GEp
 GMp
d

m
GEp
GMp
 m
Pt ( Ebeam  Ee )

tan e
Pl
2M p
2
Trasferimento di polarizzazione
dalla sonda elettronica al protone
diffuso elasticamente
E. Cisbani / La Sperimentazione al JLab
Separazione Rosenbluth.
Approssimazione di singolo fotone
scambiato nell’urto elastico
Drammatica evidenza dell’inadeguatezza dell’interpretazione degli esperimenti di
diffusione elastica di elettroni
Probabile necessità di considerare termini con scambio di due fotoni
 Esperimenti in corso a Novosibirsk, JLab, DESY
1
7
E-12-09-019: Cross section ratio
E-12-09-016: Double polarization
 Test per molti modelli (che includono
differenti contributi di momento
angolare dei quark)
 Studio regione di transizione tra la
SIF 2011 / L'Aquila
E-12-07-109: Polarization transfer
E. Cisbani / La Sperimentazione al JLab
Electromagnetic Nucleon Form Factors @12GeV
descrizione non- e perturbativa della
QCD
 Vincoli alle distribuzioni generalizzate
H ed E
1
8
(parity violating electron scattering)
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
JLab12
PVES
1
9
• Misura accurata della asimmetria nei processi elastici (e DIS) di elettroni
polarizzati longitudinalmente su nucleone/nucleo non polarizzato
SIF 2011 / L'Aquila
Esperimenti di Violazione della Parità
2

e
+
Z0
e
• Accesso alle costanti di accoppiamento deboli elettroni-quark (u/d) delle
correnti neutre, ovvero alla corrente debole del protone, ovvero all’angolo
di mixing debole
• Pone limiti su esistenza di nuova fisica (PVDIS, QWeak, Möller)
• Ha permesso la misura del contributo dei quark s ai fattori di forma del
nucleone (HAPPEX, G0)
• Permette la misura di importanti grandezze nucleari soppressi nei
processi elettromagnetici  PREX
E. Cisbani / La Sperimentazione al JLab

2
0
Elastic Scattering Parity Violating Asymmetry E = 850 MeV, =6° electrons on
lead
Z0 is a clean probe that couples mainly to neutrons
SIF 2011 / L'Aquila
Lead (208Pb) Radius Experiment: PREX
 0.0604 ( stat )  0.0130 ( syst )
 Statistics limited (9%)
 Systematic error goal achieved !
(2%)
Misura in ultima analisi del raggio
della distribuzione dei neutroni nel
Piombo
E. Cisbani / La Sperimentazione al JLab
0.6571
~ 0.5
ppm ppm
Importante per vincolare modelli
astrofisici
2
1
SIF 2011 / L'Aquila
Standard Model Test and more
Parity Violation Physics
E. Cisbani / La Sperimentazione al JLab
http://www.roma1.infn.it/pavi11/
Argomento centrale at Jlab
3 importanti esperimenti approvati per i 12 GeV
2
2
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
JLab12
Exotic Mesons Quest
2
3
I mesoni leggeri sono stati di due quark (q-qbar)
I numeri quantici del mesone sono determinati
dai numeri quantici della coppia q-qbar
SIF 2011 / L'Aquila
Origine del confinamento in QCD
La formazione del tubo di flusso è legata alla
auto-interazione dei gluoni attraverso la loro
carica di colore (stati ibridi q-g-qbar)
S2
S1
L
VM  (JTube=1)
J
I numeri quantici del mesone ibrido sono
determinati dai numeri quantici della coppia qqbar ed eventuali stati eccitati del tubo di flusso
gluonico
Tra questi, alcuni sono peculiari dei modi di
eccitazione del tubo di flusso
E. Cisbani / La Sperimentazione al JLab
I quark in tali mesoni sono sorgenti di un flusso
di carica di colore intrappolato in un tubo
(stringa) che collega i due quark.
mesoni esotici
2
4
 Uso di rivelatore a grande accettanza per particelle cariche e neutre
 Necessità di alta luminosità e quindi supporto di alta acquisition-rate
 Partial-wave analysis dei dati
Programma fondamentale della nuova sala D/GlueX ed in parte
della attuale e futura sala B/CLAS12
SIF 2011 / L'Aquila
 Uso di fotoni polarizzati linearmente (8-9 GeV) che possono fluttuare in
mesoni vettori
 I mesoni vettori interagiscono con il nucleone
 Il mesone diffuso (energie fino a 2.5 GeV) può risultare in un mesone
ibrido esotico
E. Cisbani / La Sperimentazione al JLab
Confinamento: Ricerca di Mesoni Ibridi Esotici
2
5
12 GeV era
Equipments
(RICH, Forward Tagger,
HD Target,
High Lumi Tracker)
SIF 2011 / L'Aquila
E. Cisbani / La Sperimentazione al JLab
JLab12
2
6
E
C
x
DC
R3
R2
R1
GeV/
c
1
p/K
TOF
p/p
TOF
K/p
RICH
HTCC
2
3
4
5
LTCC
LTCC
TOF
6
7
8
9
10
HTCC
HTCC
full pion / kaon / proton separation in
2–8 GeV/c range
p/K separation of 4-5  @ 8 GeV/c for a
rejection factor ~1000
Solenoid
PCAL
Torus
Aerogel mandatory to separate hadrons in the 2-8
GeV/c momentum range  collection of visible
Cherenkov light  use of MA-PMTs
INSTITUTIONS
ARGONNE NL
INFN
Bari, Ferrara, Genova,
Frascati, Roma/ISS
E. Cisbani / La Sperimentazione al JLab
TOF
SIF 2011 / L'Aquila
RICH detector for CLAS12
GLASGOW U.
JLAB
Option under investigation:
proximity focusing RICH + mirrors (innovative geometry)
U. CONN
UTFSM (Chile)
2
7
SIF 2011 / L'Aquila
E. Cisbani / La Sperimentazione al JLab
New RICH geometry
Adapted from L. Pappalardo Roma 2011
Aerogel
Flat Mirror + Aerogel
Active Photon Detector
2
8
RICH preliminary prototype
8
R8900
MA-PMTs
Aerogel
Electronics
Maroc2 front end electronics
developed for nuclear medicine
• preamplifier, adjustable from 1/8 to 4
• ADC, about 80fC per channel
10
H8500
SIF 2011 / L'Aquila
Hit distributions
aerogel n=1.05
2cm
3cm
aerogel n=1.03
Ebeam
(GeV)
Aerogel
<d>
(cm)
<R(p)>
cm
t (cm)
n
10
1
1.05
35.1
11.2
10
2
1.05
34.6
11.1
10
3
1.05
34.1
10.9
10
3
1.03
48.8
12.0
4
1
1.03
49.8
12.2
N.B. 1 and 2 cm means 2 or 3 blocks of 1 cm
3cm
integrated
distributions
of hits above
threshold
E. Cisbani / La Sperimentazione al JLab
1cm
3
0
Photo-production is the ideal tool:
• linearly polarized photon beam (NEW!)
• large acceptance detector (CLAS12)
Forward Tagger
E’
0.5-4.5 GeV
n
7-10.5 GeV
q
2.5-4.55 deg
Q2
0.007 – 0.3 GeV2
W
3.6-4.5 GeV
Photon Flux
5 x 107 /s @ Le=1035
E. Cisbani / La Sperimentazione al JLab
The study of the light-quark meson spectrum
and the search for exotic quark-gluon
configurations is crucial to reach a deep
understanding of QCD:
• identify relevant degrees of freedom
• understand the role of gluons and the origin of
confinement
Quasi-real photoproduction with CLAS12
(Low Q2 electron scattering)
Forward
Tagger
CLAS12
e-
γ*
eAdapted from R. De Vita, Roma/2011
p
Tracker
Electron angle
Hodoscope
Photon veto
Calorimeter
SIF 2011 / L'Aquila
Meson Spectroscopy in CLAS12
Electron Momentum/Energy
3
1
Polarized target of high dilution factor made of Deuterium Hydride
• Longitudinal and Transverse polarization: 75% H and 40 % D polarization
• Relaxation time: > 1 year
• Data taking: ~ months
• Weak holding field (BdL ≤ 0.1 Tm)
• Wide acceptance
• Polarization procedure: ~ 3 months
E. Cisbani / La Sperimentazione al JLab
- Dilution refrigerator
INFN contribution: - Raman analysis of HD gas
- NMR for polarization monitoring INFN
dilution
refrigerator
Run with HD-Ice & photon beam starts on Nov 19, 2011
Test of HD-Ice & electron beam scheduled on May, 2012
In-beam cryostat
From P. Rossi
SIF 2011 / L'Aquila
HD-ice: polarized frozen spin HD target
Comparison of signal
over background ratio:
HD versus conventional
polarized target
3
2
Uva
JLab
INFN
Rutgers U.
College WM
U. of Glasgow
Norfolk State U.
Carnegie Mellon U.
U. of New Hampshire
E. Cisbani / La Sperimentazione al JLab
Large luminosity
Moderate acceptance
Forward angles
Reconfigurable detectors
SIF 2011 / L'Aquila
SBS Spectrometer in Hall A
SiD
JLab12 Responsibility:
• Front Tracker (GEM+SiD)
• Readout Electronics
3
3
Luminosity
(s·cm2)-1
Tracking Area
(cm2)
GMn - GEn
up to 7·1037
GEp(5)
SIDIS
Resolution
Angular
(mrad)
Vertex
(mm)
Momentum
(%)
40x150
and 50x200
<1
<2
0.5%
up to
8·1038
40x120,
50x200 and
80x300
<0.7
~1.5
~1
0.5%
up to 2·1037
40x120,
40x150 and
50x200
Large
Area
~ 0.5
~1
<1%
High
Rates
SIF 2011 / L'Aquila
Experiments
E. Cisbani / La Sperimentazione al JLab
Different (e,e’h) experimental configurations
Down to ~ 70 mm
spatial resolution
Maximum reusability: same trackers in different setups
3
4
High Background Rate (up to):
(low energy  and e) 1 MHz/cm2
Drift
NO
MPGD
Silicon
MHz/mm2 MHz/mm2
High Resolution (down to):
Achievable
70 mm
50 mm
30 mm
Large Area:
from 40×150 to 80×300 cm2
Doable
Very
Expensive
… and modular: reuse in
different geometrical
configurations
YES
GEM
E. Cisbani / La Sperimentazione al JLab
System Requirements
Tracking Technology
SIF 2011 / L'Aquila
Choice of the technology
mMs
Flexibility in readout geometry
and lower spark rate
3
5
GEM foil: 50 mm Kapton + few
mm copper on both sides with
70 mm holes, 140 mm pitch
SIF 2011 / L'Aquila
GEM working principle
Ionization
E. Cisbani / La Sperimentazione al JLab
Multiplication
Multiplication
Multiplication
Readout
Strong electrostatic
field in the GEM holes
Recent technology: F. Sauli, Nucl. Instrum. Methods A386(1997)531
Readout independent from ionization and multiplication stages
3
6
GEp(5) SBS
Front Tracker
Geometry
SIF 2011 / L'Aquila
SBS Tracker GEM Chambers configuration
E. Cisbani / La Sperimentazione al JLab
x6
 Modules are composed to form larger
chambers with different sizes
 Electronics along the borders and
behind the frame (at 90°) – cyan
and blue in drawing
 Carbon fiber support frame around
the chamber (cyan in drawing);
dedicated to each chamber
configuration
X(4+4)
Back Trackers Geometry
3
7
SIF 2011 / L'Aquila
MonteCarlo + Digitazation + Tracking
High  + e background hits
 MHz/cm2
Bogdan Wojtsekhowski + Ole Hansen
+ Vahe Mamyan et al.
(Signal is red)
E. Cisbani / La Sperimentazione al JLab
6 GEM chambers with x/y readout
Use multisamples (signal shape)
for background filtering
3
8
SIF 2011 / L'Aquila
Assembling the first 40x50 cm2 module
Stretching
E. Cisbani / La Sperimentazione al JLab
Stretcher design
from LNF /
Bencivenni et al.
Use stretching and spacers
to keep foil flat
Foil Tension:
T = 2 kg/cm
Spacer Sector: S = 170 cm2
Expected maximum pressure
on foil
P  10 N/m2

Maximum foil deformation:
u  0.0074 * P * S / T = 6.4 mm
Gluing the next
frame with
spacers
3
9
E. Cisbani / La Sperimentazione al JLab
SIF 2011 / L'Aquila
Beam test @ DESY / Full Module Size 40x50 cm2
4
0
GEM  FEC  MPD  DAQ
SIF 2011 / L'Aquila
Electronics Readout (GEM and SiD)
Up to 10m
twisted,
shielded
copper cable
(HDMI)
75 mm
Passive backplane
(optional)
Main features:
• Use analog readout APV25 chips (analog and time information)
• 2 “active” components: Front-End card and VME64x custom module
• Copper cables between front-end and VME
• Optional backplane (user designed) acting as signal bus, electrical
shielding, GND distributor and mechanical support
E. Cisbani / La Sperimentazione al JLab
49.5 mm
2D Readout
8 mm
4
1
Chamber doublet
Dipole
Track
E. Cisbani / La Sperimentazione al JLab
SD
(x/y)
SIF 2011 / L'Aquila
+ Small Silicon Detector
Angular Range
4
2
21 Set 2009 / CSN III
JLab12 - E. Cisbani
42
5mm
10mm
8.5mm
A
5mm
B
Disegno custom per JLAB12
da un wafer di 6” (152mm)
D
A
B
C
103500
10mm
SIF 2011 / L'Aquila
8.5mm
E. Cisbani / La Sperimentazione al JLab
6.5mm
D
C
4
3
Fan Out PCB
E. Cisbani / La Sperimentazione al JLab
23 cm
44
SIF 2011 / L'Aquila
fori di fissaggio
30 cm
4
4
Si
Detector
X
X
Form
Factors
X
X
Parity
Violating
Electron
Scattering
X
TMDs,
nucleon
spin
structure
Meson
Study
HD
Target
RICH
X
X
Forward
Tagger
X
SIF 2011 / L'Aquila
GEM
Tracker
Equipment
Physics
E. Cisbani / La Sperimentazione al JLab
Equipment / Physics Matrix @ 12 GeV
Intensa attività di sviluppo tecnologico per un esteso programma di fisica
4
5
SIF 2011 / L'Aquila
QCD and confinement
Large Distance
Low Energy
Perturbative QCD
DIS Scattering
Parton models
Strong QCD
Spectroscopy
Phenomenological Models
 ~ QED  QCD
JLab
offers
High luminosity
Polarization (initial and final states)
High beam stability
Complementary Equipments
Dedicated, optimized detectors
www.iss.infn.it/webg3/cebaf
E. Cisbani / La Sperimentazione al JLab
Small Distance
High Energy
4
6