Transcript November 17th, ‘99 Charged Kaons

CERN, 7 Settembre 2005
Conference room 40-R-B10
09:30
10:30
11:00
Iacopini:
Fantechi
Valente
Introduzione
Status report Veto
Test Beam svolto ai LNF, stato simulazioni,
ripartizione attivita' tra le Sez. Interessate
Odoscopio
Gigatracker
11:40
12:10
Piccini
Scarpa
12:40
Pranzo
14:00
Illustrazione richieste 2006
s
d
n n
K   
+
E. Iacopini, 7 Sett. 05

Nota scritta
Si
Nota scritta
Ke3 pubblicato
Kmu3 in progress
90%
Presentato
in CSN1
80%
OK
Ferrara:
Dottorando: Massimiliano Fiorini, da Marzo 2003 a FebbraioMarzo 2006. Proseguirà con un assegno PRIN2005.
Assegnisti: Marcella Scarpa, che finisce con il 2005
Chiara Damiani, che continuerà l’attività con un nuovo assegno
da Marzo 2006.
Firenze:
Francesca Bucci, assegnista dal 1/7/05, per 2 anni
Napoli:
1 assegnista al 50 % (scadenza contratto Febbraio 2007)
LNF:
al momento, nessuno.
Perugia:
Raggi termina la borsa di dottorato nell'ottobre 2005.
Imbergamo, dottorando senza borsa, conclude il dottorato nel
2005 come Raggi. Ha un assegno di ricerca fino a settembre.
Piccini, assegnista INFN, ha iniziato il suo assegno di ricerca nel
maggio 2005 e nel 2006 avrà il prolungamento al secondo anno
Pisa:
Dottorandi: Lamanna e Venditti
Il Lamanna si addottorera' entro la fine dell' anno
e avrà subito un assegno. Poi ci sono Sergio e
Gianmaria assegnisti SNS, entrambi in scadenza
fine 2006, ma Sergio ha gia' avuto un rinnovo
Roma1:
al momento, nessuno.
Torino:
Dottorandi:
Silvia Goy Lopez e' al secondo anno,
Simone Bifani e' al primo anno
• Proposal submitted to SPSC on
June 11, 2005:
“We propose to measure the very rare decay
K+  + nn 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
A. Ceccucci August 31 2005 - Cambridge
Recent developments in the
rare kaon decay community
• A few months ago the Fermilab Directorate endorsed the PAC
recommendation not to pursue K+  + nn at the Main Injector
The physics of K+  + nn 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 m to e conversion experiment (MECO) and the K0  0 nn
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
A. Ceccucci August 31 2005 - Cambridge
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)
• It is my understanding that 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 University in addition to National
Labs (at least for BNL)
A. Ceccucci August 31 2005 - Cambridge
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++ n n"
A. Ceccucci August 31 2005 - Cambridge
CERN Program and Plans
introduction to Round Table discussion on
The Future of High Energy Physics
ECFA-EPS Joint Session at HEPP-EPS 2005
International Europhysics Conference on
High Energy Physics
Lisbon, July 21 -27, 2005
Jos Engelen
CERN
From Medium Term Plan, CERN/2615
Legend:
Approved
Under Consideration
2004 2005 2006 2007 2008 2009 2010
LHC Experiments
PS and SPS Shutdown
•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
ALICE
ATLAS
CMS
LHCb
TOTEM
Other LHC Experiments
(e.g. MOEDAL, LHCf)
Non-LHC Experimental Programme
•Very limited neutrino programme (in scope)
SPS
COMPASS
•New initiatives include K++nn; why not K00nn..?
NA48
NA60
Neutrino / CNGS
New initiatives
•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)
OTHER
FACILITIES
EURISOL
Design to
Study
(including
beta
beams)
•New
initiatives
appear
in Budget
Plan
from 2006 (or maybe 2007)
AD
ISOLDE
onwards
n-TOF Neutron
CAST
DIRAC
Test Beams
•Accelerator R&D includes EU funded networks, joint projects, design
studies
North Areas
West
Areas
•Linear colliders: Eurotev
(‘generic’)
and CLIC (CERN and partners,
No fully-fledged NeutrinoEast
Factory
Design
Study yet (2008 if EU support)
Hall
‘collaboration’, feasibility proof
by 2009)
R&D
(Detector & Accelerator)
13
12
+
K decays in 50 m
11
/ 3 10
10
x10
+
12
inc. p
+
K / 
6
9
x 10
8
-2
7
6
Choice of
K+
momentum:
(for 400 GeV/c proton momentum)
x 10
5
K+ / Total beam
-2
x 10
-3
4
3
x 10
-14
+
+
K decays in 50 m
/ Total beam
+
K flux
12
/ 3 10 inc.p)
Acceptance
2
x 10
1
x 10
8
-1
0
40
50

Acc. K to  nn
/ Total beam
60
70
+
80
90 100 110 120 130 140 150
K momentum [GeV/c]
(2 RMS)
1.5
K+
+
n
n
800 MHz
(/K/p)
10 MHz Kaon
decays
Solo i rivelatori upstream sono esposti
a 800 MHz di fascio (8.6% K) …
G. Ruggiero 1 Sett. 2005 Cambridge
Background kinematically
constrained
Decay
BR
Km2
0.634
+0
0.211
++- (00)
0.070
92% of total background
G. Ruggiero 9/1/2005 Cambridge
+0 forces us to split the signal region
Background not kinematically
constrained
Decay
Ke3
Km3
Km2g
+0g
Ke4
Km4
BR
0.049
0.033
5.5×10-3
1.5×10-3
4×10-5
1×10-5
8% of total background
Spoils the signal region
Background rejection
Goal of P326: S/B ≈ 10
~10-12 rejection
2-steps background rejection:
1) Kinematical rejection
Region I: 0 < m2miss < 0.01 GeV2/c4
Against Km2, +0
Region II: 0.026 < m2miss < 0.068 GeV2/c4
Against +0, ++-, +00
2) Veto and Particle ID
g, m, charged particles
m –  - e separation
G. Ruggiero 9/1/2005 Cambridge
Sources of background
Kinematical rejection inefficiency
Resolution effects
Non gaussian tails
Beam pile – up
Simulated using Flyo
Simulated using GEANT4
Simulated using Flyo
Veto and particle ID inefficiency
RICH
m – veto
g – veto
Simulation (Jurgen)
Simulation (Oleg)
Parameterization (Simulation in progress by Rome)
(Data in progress: LKr by NA48/2, ANTI by Frascati)
Resolutions (Flyo MC)
Gigatracker
300 x 300 mm pixels
0.4% X0 per Spibes
Simple reconstruction
2% inefficiency per station
Double
Spectrometer
80mm resolution in X and
Y hits (125 mm per view)
0.5% X0 per chamber
Track momentum from fit
Angle from first 2
chambers
Fully efficient
Results:
s(PK)/PK = 4.2 x 10-3
s(qK) = 16.7 mrad
s(P)/P = 0.23% + 0.005% P (GeV/c)
s(qK) = 60 – 20 mrad (P = 10 – 50 GeV/c)
+0 m2miss resolution
qK
qK
q
Ptrack
PK
Not gaussian tails (GEANT4)
Simulation:
Toy simulation of the Double
Spectrometer, based on GEANT4
Interactions:
+0 30-35 GeV/c
Electromagnetic, Hadronic
Reconstruction:
Average material 0.5% X0 (no
straws geometry)
d-ray production allowed
No digitization, coordinates
smeared with gaussians
Effects:
Tails in the
reconstructed
momentum and angle:
Approximation:
Non gaussian effects in the
Gigatracker not taken into account
Beam pile-up (Flyo)
Simulation:
Accidental track superimposed in Gigatracker to the
kaon track
Accidental track generated according to the beam
momentum bite, dimension and divergence
Rate: 800 MHz
SPIBES: time resolution 200 ps, inefficiency 2%
HODOSCOPE: time resolution 80 ps
Effect:
The downstream track can be matched with the
wrong track: danger expecially for  0
Analysis:
Only upstream tracks within 500 ps from the
downstream track are considered “good” upstream
tracks: 32% of events have >1 good track in Giga
Track choice based on c2 from DT and CDA
About 1.7% of events matches the wrong track
Veto and particle ID
g – Veto:
RICH (Simulation by
Jurgen):
g inefficiency parameterization
17 m long, 1.0 atm Ne
JURGEN
ANTI
LKR

m – Veto (Simulation by
Oleg):
hm-veto = 10-5
IRCs,
SAC
E range
Inefficiency
< 50 MeV
1
(0.5, 1) GeV
10-4
> 1 GeV
10-5
< 1 GeV
1
(1,3) GeV
10-4
(3,5) GeV
10-4 - 10-5
> 5 GeV
10-5
All
10-6
Selection (1)
Number of tracks
1 positive downstream track (hit in all the 6
chambers)
Choice
of the upstream track using minimum
Detector
geometry
2 (prev. slide)
cDownstream
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 ID
Not muons in RICH or MAMUD
Not electrons in RICH or LKr (LKr with 10-3 inefficiency of e – ID)
Selection (2)
Fiducial decay region
5 m < Zvertex < 65 m (from the final collimator, Zvertex defined as the Z
coordinate of the point closest to both the tracks)
Cut on momentum
15 GeV/c < Ptrack < 35 GeV/c
Specific cuts
DPtrack/Ptrack < 2.5×s(P)/P (against the not gaussian tails)
CDA < 0.8 cm (against the tails from the beam pile – up)
Kinematics
REGION I: 0 < m2miss < 0.01 GeV2/c4
REGION II: 0.026 < m2miss < 0.068 GeV2/c4
Some remarks
Fiducial decay region: 60 m (5m < Zvertex < 65 m)
Kaon Flux: 4.8×1012 decay/year in the fiducial region
Detector Layout described in the proposal:
Straw chambers 5cm inner radius displaced in x according to the
positive beam deflection in the spectrometer
Magnets 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
+0
Acceptance after all the cuts: Acc = (1.3 ± 0.1) × 10-4
Assumption: independence between kinematical rejection inefficiency
(hkin) and selection acceptance
NI,II = hkin×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)
Photon veto inefficiency:
h(0) = 2 × 10-8
Expected events:
N(+0) = Fkaon × BR × Acc × h(0) = (2.7 ± 0.2) / year
–
–
–
Region I: 1.7 / year
Region II: 1.0 / year
Nngaus ~ 0.5 / year, Npileup ~ 2.2 / year

m
n
Acceptance after all the cuts: Acc=(8 ± 2) × 10-6
Same procedure as for +0 to extract the acceptance
Muon veto inefficiency:
hMAMUD (m) = 10-5 (MAMUD)
hRICH (m) = 5 × 10-3 (RICH) (conservative)
Assumption: MAMUD and RICH rejection inefficiencies independent
Expected events:
N(Km2) = Fkaon × BR × Acc × hRich (m) × hMAMUD (m) = (1.2 ± 0.3) / year
–
–
–
Region I: 1.1 / year
Region II: <0.1 / year
Nngaus ~ 0.4 / year, Npileup ~ 0.8 / year
Two body background vs
Spibes performances
2 body background events
2 body background events
Total
Total
+0
Km2
s(t) Spibes ns
+0
Km2
h Spibes ineff
Other backgrounds
Ke3:
Acceptance ~12% (Flyo)
h0 ~ 3×10-8
Positron ID: hLKr × hRICH < 10-3 × 10-3 (conservative)
NEGLIGIBLE
Km3:
Acceptance ~17% (Flyo)
h0 ~ 3×10-8
Muon ID: hRICH × hMAMUD < 10-5 × 10-2 (conservative)
NEGLIGIBLE
+00:
High suppression from kinematics and g veto
NEGLIGIBLE
G. Ruggiero 9/1/2005 Cambridge
Signal Acceptance
Selection applied on nn events generated with FF
(from CMC)
Effects not taken into account:
Random veto
Accidental loss due to hit multiplicity cuts
Straw inefficiency
Loss due to cuts in MAMUD for muon ID
BR(+nn)=8×10-11 (SM)
Signal Acceptance
Results
REGION 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 cuts
Ntrack=1:
cuts 8% of events
Geometry: cuts 10% of events
Momentum: cuts 50% of events
Pile – Up: cuts 12% of events
Signal and backgrounds / year
Signal
+0
Km2
Ke4
++- and 3-tracks
+0g
Km2g
Ke3, Km3 ,others
Total bkg
Total
~65
2.7±0.2
1.2±0.3
2±2
1±1
1.3±0.4
0.4±0.1
negligible
9±3
Region I
~16
1.7±0.2
1.1±0.3
negligible
negligible
negligible
0.2±0.1
Region II
~49
1.0±0.1
<0.1
2±2
1±1
1.3±0.4
0.2±0.1
3.0±0.2
6±3
Results: S/B
S/B (Total) = 7.6 ± 2.0
S/B (Region I) = 5.2 ± 1.1
S/B (Region II) = 8.9 ± 3.6
Some S/B dependence on detector parameters
uncorrelated errors
Hodo time resolution
80 ns
Spibes time resolution
200 ns
Spibes inefficiency
2%
Tentative sharing of construction
responsibility (sept. 05)













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 - Cambridge
Element
Cost (MCHF)
Comments
BEAM LINE
0.4
Modified K12 line
CEDAR
0.5
Replacement of photon detectors
GIGATRACKER
2.7
VACUUM
1.0
ANTI
4.2
STRAW TRACKER
2.4
6 straw chambers
MNP33/2
2.5
(1170 + prolongation of He tank)
CHOD
0.9
(0.9)
LKR
2.0
!!!
RICH
4.0
Indication
MAMUD
1.5
Cost of iron ≈0.5 MCHF
SAC, IRC1 & IRC2
0.4
Shashlik or PbWO4
Trigger & DAQ
1.5
TOTAL
24.0 (7.2)
(1.4)
Assuming 0.13 mm CMOS technology
Addition of 20 large diffusion pumps
(4.2)
(0.7)
CKM estimate + 40% for the electronics
MGG-RPC
New supervision system and R/O
L0 HW, L1 SW
Gigatracker
0.7-1.0 M€ (assumendo 50% sharing)
Anticounters
2.8-3.4 M€
Chod
0.5–0.7 M€
Trigger
0.5-0.8 M€ (assumendo 40% sharing)
TOTALE
4.5-5.9 M€
(Nella proposta sono quotati 7.2 MCHF = 4.8 M€ )
Il 27 settembre, verrà presentata all’SPSC una
richiesta di 30 gg di run per il 2006 sulla solita linea di fascio
K12 principalmente per
- misurare l’inefficienza di osservazione dei fotoni con il LKr
- misurare il BKGR da pi/k interagenti con il gas residuo
- determinare l' alone del fascio
- effettuare i tests necessari sui prototipi dei nuovi rivelatori
(Cedar, hodo, sensori gigatracker …)
Common Fund 2006
Nella riunione di Cambridge, lo Steering Committee ha
definito in 93.5 kCHF il Common Fund 2006 di NA48/2.
Sulla base del MoU esistente, questo significherebbe
93.5*0.3 = 28.05 KCHF ≈ 19. Keuro (1euro=1.5CHF)
Richiesti nei moduli 15k
P326 Run Operating expenditures in 2006
Nella riunione di Cambridge, lo Steering Committee ha
definito in 165.5 kCHF le spese da sostenere in comune
per il run 2006, relativo all’R&D di P326.
Nell’ipotesi di 1/3 a carico INFN, questo significa
165.5/3 = 55.2 KCHF ≈ 37.0 Keuro (1euro=1.5CHF)
Richiesti nei moduli 20k + 20k (Pool) = 40k
Il sistema attuale è obsoleto e non più supportato e richiede già da
tempo la sua sostituzione, anche perchè la persona che, comunque,
lo conosceva, è ormai in pensione da tempo. Abbiamo rimandato
fino a che è stato possibile, ma ormai l’operazione è divenuta
improcrastinabile per ragioni di sicurezza dell’apparato.
Per passare al nuovo sistema supportato al CERN per LHC, il costo
Previsto (hardware + man-power) è di 500 kCHF.
Date le ristrettezze finanziarie comuni, vorremmo comunque cercare di
sbloccare la situazione, attraverso un finanziamento straordinario ad hoc
dell’INFN di
150 k€ .
SPARES