CMS: stato e programmi futuri - pd.infn.it · la presa dati tracking performance ad alto pile-up...
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Transcript of CMS: stato e programmi futuri - pd.infn.it · la presa dati tracking performance ad alto pile-up...
1
Sommario:
- LHC & CMS, 10 fb-1 di dati: ~2 anni “meravigliosi”
- Performance & running: DT & Tracker
CMS: stato e programmi futuri
pp→m+m-e+e- + X
-“Highlights” di Fisica (Higgs e non solo),
attivita’ padovane di analisi : T.Dorigo, 35’
- Prospettive: “Long Shutdown 1” (2013/14) e oltre
Tracker ( N.Bacchetta,)
DT
- richieste 2013
U.Gasparini, CdS 10/7/2012
2
LHC @ 7 + 8 TeV (2012 vs 2010/11)
Nei primi 2 mesi di run nel 2012 LHC ha fornito ~6 pb -1 di luminosita’ integrata
( > Ltot(2011)) per collisioni pp con 4 TeV/fascio (max inst. lumi ~7∙1033cm-2s-1 ;
~1400 bunches, 50 ns bunch spacing )
-il run verra’ prolungato di ~2 mesi (fine anno) rispetto alla schedula iniziale
-run heavy-ions postposto a inizio 2013
attesi: ~30 fb-1 in totale
prima del “long
shutdown” (2013/14)
<Nvtx>~25 : “ambiente”
non facile…
3
Prestazioni globali
L’ apparato ha funzionato egregiamente
in tutte le sue componenti… Ottima efficienza di ricostruzione
& identificazione degli “oggetti fisici”
- prestazioni stabili
in funzione del pile-up
4
DT: prestazioni rivelatore
-Il rivelatore ha operato stabilmente; < 1% canali morti,
> 99.5% DAQ “live time”; ottime prestazioni di trigger, timing dei muoni
e ricostruzione
(piu’ che soddisfacente ottimizzazione di calibrazioni, configurazioni
di trigger, allineamenti)
-Detector Control System affidabile, tools di data quality monitoring
ben sviluppati e integrati nel software generale dell’ esperimento
-sistema consolidato di shifts+ expert on-call ( man-power al Cern
ragionevolmente limitato)
efficienza del L1 local trigger nelle camere a mu r.m.s. of Rec.hit residuals distributions
~220 mm
problemi noti
(e risolti)
6
Muon reconstruction
A pT>100 GeV, le camere
migliorano sensibilmente la
risoluzione in momento del
sistema globale di
tracciamento
(importante e.g. per ricerche
di risonanze nella regione di
alta massa )
Allineamento:
geometria
“ideale”
7
Running & operations
7
powerful Web-based monitoring tools +
DB interfaces developed
- Continous upgrade of cross-DAQ applications +
Tracker: prestazioni
moduli operanti
tutti i moduli
8
fraction of alive channels:
97.75%
- la qualita’ dei dati presi e’ molto buona:
solo una minima parte viene esclusa
dalla certificazione per le analisi di fisica (1.6%) [principalmente periodi di transizione HV ON OFF ]
CMS Preliminary
- il rivelatore sta funzionando molto bene
- il numero di canali non operativi e’ < 2.5%
- i canali operanti sono efficienti e stabili
rispetto al 2011
99.5%
M. Tosi
9 9
• Le prestazioni della
ricostruzione vengono
monitorate sia online che
offline.
• In particolare si sono
sviluppati nuovi strumenti
per poter monitorare le
prestazioni in funzione della
luminosita’ e del PU durante
la presa dati
tracking performance ad alto pile-up
L’algoritmo di ricostruzione delle tracce e’ stato ottimizzato
in previsione del run 2012 a piu’ alta luminosita’ e Pileup
Evento con PU ~ 50
<PUpeak>~27
<PUpeak>~22
<PUpeak>~10
10
Physics Performance &Dataset (PPD)
New project in 2012 to coordinate:
Data Certification
Data Quality Monitoring
Calibration/Conditions/Database
Physics Validation
MonteCarlo production & data
reprocessing (also for Upgrades)
2012 certified
‘Golden’: 5.19 fb-1 (85%)
Muon: 5.62 fb-1 (92%)
Responsible also for Daily
Offline Operations
Coordination with Trigger,
Offline, Run coordination,
Physics and Computing
Regular reprocessings to have the
best ECAL calibration for H->gg
P. Azzi
11
PPD (II)
Evolution and extension to the Upgrade of the Particle Flow
Optimal combination of information from all subdetectors
Returns a list of reconstructed particles e,μ,γ, charged and neutral hadrons
Used in the analysis as if it came from a list of generated particles
Used as building blocks for jets, taus , missing transverse energy , isolation and PU particle identification
Vast majority of CMS analyses (e.g. Higgs) using GED. Task force helps the coordination/training/code developments so that this number becomes 100%.
11
Made possible by CMS
granularity
and high magnetic field
New “Global Event Description” (evoluzione del Particle Flow)
PPD(III): “Pileup” task force
12
Started Dec 2011 in preparation
for high PileUp of 2012 run.
Obtained:
A factor 2.5 in reconstruction
speed
below ~15” per event on
average
Much reduced memory use
Well under 2 GB
Physics performance unchanged
E.g. no explicit pT threshold
on tracks Reconstruction time/mem without any
output module on a very pessimistic data
sample to show maximum improvements.
Not average performance.
Nel 2012, e’ stata fondamentale un’ottimizzazione del codice
di ricostruzione, per far fronte all’ aumentato pile-up e stare in tempi ragionevoli, a parita’ di
prestazioni della ricostruzione stessa.
13
Attivita’ padovane & responsabilita’
-Commissioning/controllo rivelatore DT :
- local trigger sync., time calibrations,
on-line / off-line DataQualityMonitoring
-Sviluppi / maintenance DT DAQ / DCS
-Physics Performance, data certification
-DT & Tracker offline Databases
-Tier2 operations, data management
- attivita’ per “Long Shutdown”
- simulazioni per upgrade/SLHC
- Analisi di fisica :
Presentazione
di T.Dorigo
Responsabilita’ di Padova in CMS: R.Carlin L1 trigger coordinator
P.Azzi Physics Performance & Dataset coord.
T.Dorigo chair CMS stat. committee
N.Bacchetta Tracker phase1 upgrade techn.coord.
M.Tosi Tracker/DQM resp.
P.Zotto deputy DT upgrade coord.& mu-tk trg.contact
S.Ventura DT/DAQ resp.
F.Montecassiano DT electronic coord.
A.Branca DT /DQM resp.
A.Meneguzzo DT prompt-offline analysis resp.
A.Gozzelino DT L1 emulator sw.
I.Lazzizzera DT upgrade simul.
E.Torassa CMS simulation prod. coord.
Upgrade CMS projects
14
- Technical Proposal being published
end of 2011
-Dealing with “Phase-1” (up to 2020)
- Substantial contributions from Padua
- pixel upgrade
- muon trigger upgrade
LHC Performance Projections
CDS, 10 JULY 2012 Nicola Bacchetta 15
Phase 1 : 13/14 TeV - 500fb-1 Phase 2 : 13/14 TeV - 3000fb-1
LS1 13-14
713/14 TeV
Injection upgrade
PS batch compression
SPS scrubbing
LS2 18 (19?)
Injection upgrade
Linac4 (H-)
PSB-PS 1.42GeV
RF upgrades PS - SPS
aC coating SPS (?)
LS3 22-23
>30
LHC Interaction region upgrade
Triplets (lower β*)
Crab cavities (beam crossing leveling)
b-b compensation (lower beam loss)
Lpeak 1035 Hz/cm2
Lleveled 5 1034 Hz/cm2
2 1034
1034
o Goal is 25ns, 50ns not ruled out
o Performance projection and
schedule will likely not be well known
before restarting in 2015
o Leveling mitigates pile-up but
integrated luminosity could be limited
due to SEE & UFOs effects
12
7 1033Hz/cm2
à 50 ns
30fb-1
25 ns
2e34 likely before LS2
?
N.Bacchetta
CMS Upgrade Strategy
CDS, 10 JULY 2012 Nicola Bacchetta 16
Phase 1 : 13/14 TeV - 500fb-1 Phase 2 : 13/14 TeV - 3000fb-1
LS1 13-14 LS2 18 (19?) 12
20fb-1
LS3 22-23 >30
Assume 25ns operation, or lumi-leveling at 50ns as a fall-back
For Phase 1 (up to LS3)
Design to operate at <PU>=100 (eg Pixel BandWidth)
Simulate performance for <PU>=50 as a “baseline” and degradation for <PU>=100
For Phase 2
Simulate and design for <PU>=100 as a “baseline” and degradation for <PU>=200
Prepare for significant peak luminosity and pile-up even before LS2
Pixels – HF – L1-Trigger ready before LS2
New beam-pipe – Pixel cooling system – Pixel pilot blade installation in LS1
Optical splitting for ECAL installation in LS1 for L1-Trigger
Need an extended TS in 2016 for Pixels installation, not in current LHC schedule
Maintain flexibility to adjust to evolving performance, schedules and funding
Develop a consolidated schedule and model for the funding to allow the right strategic
decisions (subset included in the TDR)
LS1 projects 2013 - 2014
In production
Critical-path construction milestone-series to feed into TC global
planning
Pixels and HCAL TDRs
Conceptual Design Reviews have been held
Submit to LHCC 2012 for endorsement before next RRB - request for
physics motivation and for summary documents provided with TDRs
in advance
July: internal referee-readers, August: Collaboration review
Second half of July: review physics case – CADI lines created for TDR
chapters
(plus AN) – ARCs assignment in progress
July: review of cost estimates (FB sub-committee)
L1-Trigger TDR
CDR (two parts) in September / November
Submit to LHCC early 2013
Phase 2 TP end 2014 – TDR in 2016
CDS, 10 JULY 2012 Nicola Bacchetta 17
CMS Upgrade Strategy
Data rates:
Zero suppression means data rates depend on occupancy.
Above design data rates & pileup now due to 50ns bunch
spacing
6E33 @ 50ns ~30 pileup
Several bottlenecks:
Buffer space in ROC
Layer 1: 16% Loss at 2E34 (25 ns)
Optical readout of modules
Saturates at 1.3E34 (50ns)
or 2.6E34 (25 ns)
FED to event builder
S-Link/Myrinet replacement
All Addressed in upgrade
CDS, 10 JULY 2012 Nicola Bacchetta 18
Present Pixel Limitations
Performance Enhancements
CDS, 10 JULY 2012 Nicola Bacchetta 20
New geometry:
o Improved resolution at low pT and high η
o Reduced degradation from inefficiencies
o Vertex resolution benefits from both
o Improved efficiency
on all η ranges at high
pileup.
o Improvement at 100
pileup even more
striking
New ROC chip
CDS, 10 JULY 2012 Nicola Bacchetta 21
TBM
digital
LCDS
convert
Digital
Logic
Translator
Te
st s
tructs
ture
s
Step 1 (Jan. 2012, 250nm CMOS)
ROC for Layers 2-4 (PSI46dig)
pixel rates < 250 MHz/cm2
DC level changes
DB buffer 3280
TS buffers 12 26
ROC level changes
readout buffer with data throttling
ADC (8bit) for pixel pulse heights
160Mbit/sec serial digital out
6th metal less power droop
reduced X-talk lower thresholds
no changes to PUC & CD architecture
Step 2 (Oct. 2012, 250nm CMOS)
ROC for Layer 1 (PSI46dig+)
pixel rates < 600 MHz/cm2
Improved Column Drain Cluster (CDC)
architecture & dead time free DB
Testing new ROCs in Padova
CDS, 10 JULY 2012 Nicola Bacchetta 22
Testing ROCs:
o Necessary before committing chips to
modules as failure rate after dicing non
negligible.
o x-ray, rate characterization/calibration
Support module qualification:
o test a few sample modules in details for
quality assurance and ROC testing procedures
verification.
Testing new ROCs
CDS, 10 JULY 2012 Nicola Bacchetta 23
Testing (2012-13):
o New probe-card designed and
delivered
o Finish setting up the probe station in
Padova
o complete the debugging of the new
probe-card
o Start gaining experience testing chips,
improve on quality and setup
o support testing early module production
Phase II: Full Tracker Upgrade
CDS, 10 JULY 2012 Nicola Bacchetta 24
Radiation hardness
Ultimate integrated luminosity considered ~ 3000 fb-1
To be compared with original ~ 500 fb-1
Granularity
Resolve up to 200÷250 collisions per bunch crossing
Nominal figure of 5×1034 cm-2 s-1 @ 40 MHz corresponds to ≥ 100
collisions
Keep 20 MHz as worst-case limit
Maintain occupancy at the few % level
Requires much shorter strips!
Improve tracking performance
Reduce material in the tracking volume
Improve performance @ low pT
Reduce rates of nuclear interaction, g conversions, bremsstrahlung…
Reduce average pitch
Improve performance @ high pT
Phase II Full Tracker Upgrade
CDS, 10 JULY 2012 Nicola Bacchetta 25
Designing an Outer Tracker with:
Higher granularity
Enhanced radiation hardness
Improved Tracking performance (.l. lighter!)
L1 Track finding capability
Reconstruct tracks above ~ 2.5 GeV
With ~ 1mm z0 resolution
All the necessary R&D activities are ongoing
Still far from a fully defined concept
But a lot of progress has been made already
Encouraging indications that the goals could be met
Need to converge on an optimal design in the next ~ 2 years
Draft schedule developed for delivery in LS3
Phase 2 TP end 2014 – TDR in 2016
Key new feature
Tracker Input to L1
CDS, 10 JULY 2012 Nicola Bacchetta 26
Silicon modules provide at the same time “Level-1 data” (@ 40
MHZ), and “readout data” (@ 100 kHz, upon Level-1 trigger)
The whole tracker sends out data at each BX: “push path”
Level-1 data require local rejection of low-pT tracks
To reduce the data volume, and simplify track finding @ Level-1
Threshold of ~ 1÷2 GeV data reduction of one order of magnitude
or more
Design modules with pT discrimination (“pT modules”)
Correlate signals in two closely-spaced sensors
Exploit the strong magnetic field of CMS
Level-1 “stubs” are processed in the
back-end
Form Level-1 tracks, pT above 2÷2.5 GeV
To be used to improve different trigger channels
m
m
mx
y z
“stub”
Tracker Input to L1
CDS, 10 JULY 2012 Nicola Bacchetta 27
Hierarchical logic to find L1 tracks
Within double-stack, each lower module is combined with two
upper modules to form Tracklets
Geometry helps to keep problem “local”
Tracklets in each layer are extrapolated to the other two
layers
Possible to find a track if there is at least one tracklet
N.B. in this layout also the outermost layer is
pixellated!
Impact on power and cost!
Remove duplicates
Concept appears to be feasible
Only defined strategy to deliver L1 tracks so far
A possible layout: long barrel
CDS, 10 JULY 2012 Nicola Bacchetta 28
Pairs of stubs are combined to form “tracklets”
Self-contained f sectors.
Each sector needs to be combined with
the two neighbouring sectors (left and
right) to “contain” ~2.5 GeV tracks.
May 25, 2012 28
6
• Outer&tracker&completely&built&with&pT3modules&
• Par7cularly&flexible&in&simula7on&studies&of&tracking&trigger:&• informa7on&from&several&layers&of&the&tracker&can&be&combined&in&a&projec7ve&geometry&
• tes7ng&ground&to&compare&the&performance&of&different&designs&and&configura7ons&
• 100#μm#×#1#mm#pixels#(in#r"φ#×#z)#• 1#mm#lever#arm#in#stacks#• trigger#layers#arranged#in#double#stacks#with#4#cm#separa?on#
Hermetic azimuthal coverage to
keep data flow local within a ladder
6 long layers = 3 Super layers
Very challenging design
6
• Outer&tracker&completely&built&with&pT3modules&
• Par7cularly&flexible&in&simula7on&studies&of&tracking&trigger:&• informa7on&from&several&layers&of&the&tracker&can&be&combined&in&a&projec7ve&geometry&
• tes7ng&ground&to&compare&the&performance&of&different&designs&and&configura7ons&
• 100#μm#×#1#mm#pixels#(in#r"φ#×#z)#• 1#mm#lever#arm#in#stacks#• trigger#layers#arranged#in#double#stacks#with#4#cm#separa?on#
Hermetic azimuthal coverage to
keep data flow local within a ladder
6 long layers = 3 Super layers
Very challenging design 15 degree sector
f arrangement within double-stack layer
Common supporting mechanics
CMSSW simulation results (work in progress)
CDS, 10 JULY 2012 Nicola Bacchetta 29
9
Stub%produc+on%efficiency%in%stacks%at%32%cm,%36%cm,%and%in%both%of%them%within%same%ladder%(product%in%gray,%measured%in%red)%• pixel%pitch%allows%sharp%threshold%at%2%GeV/c%in%simula+ons%of%single%muon%tracks%[L]%
• 5%GeV/c%threshold%is%smeared%%
pT thresh = 2 GeV/ c pT thresh = 5 GeV/ c
Generated muons with flat 0<pT<100 GeV/ c
Stub finding efficiency in layer 1
18
• Stubs&can&be&used&like&“hits&from&tracks&with&pT&above&threshold”&
• Stubs&can&be&associated&with&each&other&in&opportunely&paired&trigger&layers&to&form&tracklets&
• Associa<on&within&same&ladder&and&double&stack!&
Assuming(the(vertex(in(the(transverse(plane,(the(trajectory(can(be(fully(constrained:(simple(trigonometry(to(get(R,(pT(and(φ(
• Vertex&is&assumed&in&(x,y)=(0,0)&• Track&is&backprojected&to&vertex&with&a&straight&line&in&r&×&z%
At#least#1#tracklet#At#least#2#tracklets#At#least#3#tracklets#
“digi hit”
Tracklet finding efficiency in L1 and L3
DT upgrade plans
30
- “manutenzione
straordinaria” in LS1:
nuove FPGA boards
in trigger q-view
- Riallocazione
& nuovo trigger
sector collector
- Preparazione
per L1 con Tracker (fase 2)
- Nuovo RO
- Nuovo DT
Track Finder
(in discussione)
FPGA in Trigger q view
31
Progetto completamente padovano:
- Prototipi finali FPGA prodotti &
estensivamente testati
-Tests di radiation hardness
eseguiti con successo (PSI, LNL)
sostituzione moduli trigger BTIM (assemblaggio ASIC tecnologia ATMEL 0.5 mm)
con FPGA nella vista theta del DT local trigger
FPGA in Trigger q view (II)
32
- Gara per produzione di massa FPGA conclusa
(200 kCHF su MOFB)
- delivering time in Autunno
- on schedule per installazione durante LS1
Test di funzionalita’:
“timebox” con nuove/vecchie
schede di trigger
DT upgrade: spostamento trigger Sector Collector
33
Oggi:
Dopo shutdown:
Attivita’ principale: gruppi Torino/Bologna: sviluppo traslatori OFCu, CuOF
Padova: contributo su upgrade slow-control
Slow control upgrade
34
S. Ventura
Inheriting the
solution
developed for the
upgraded
secondary links to
control to CUOF
boards and the
OFCU-TSC
Not needed for
commissioning of
the CUOF-OFCU
chain, can arrive
later
36
DT Upgrade : oltre fase 1
Sviluppo simulazioni dettagliate per SLHC (High luminosity):
studi di nuovi algoritmi per L1 trigger di muoni DT+Tracker
Tracker-upgrade
geometry used (see Bacchetta’s slides)
50 GeV muons
Fraction of
muons passing
L1 trigger
present CMS
Muon trigger
new
algos
Detailed pile-up studies performed
<Npileup>=200
( → L~ 1035 cm-2 s-1)
37
Calcolo: T2 Pd-LNL + local cluster
- Esperienza consolidata su un notevole carico di lavoro
- sia simulazioni (scheduled processing) che
job di analisi (random CPU usage)
~1000 CPU’s,
~100% usage
~last 24 h
EVO, web-mon
outreach,
student’s demo
CMS center & local
cluster
(analisi interattiva)
I principali contributi di Fisica
38
CMS ha pubblicato dal 2010 ~140 lavori di Fisica (+ ~30 su performance
rivelatori)
Maggiori contributi padovani ad articoli pubblicati:
-Low PT physics: Bose Einstein correlation a 2 e 7 TeV
-B-physics: Misura di produzione inclusiva di quark utilizzando pp->mu X
-Exotica: ricerca di Heavy Stable Charged Particles
In cantiere:
- Higgs: search di MSSM Higgs nel processo di produzione associata bbH, H->bb
(Physics Analysis Summary (PAS) pubblicato per ICHEP2012)
- Exotica: Heavy Top Partners (PAS imminente), Heavy lepton partners of neutrinos
in Type III seesaw model (PAS imminente)
39
Personale gruppo CMS
DT: Tracker:
Le attivita’ di analisi fisica
sono comuni
Tecnologi
Percentuale CMS
Azzi 100
Bacchetta 100
Bisello 70
Dorigo 100
Giubilato 70
Paccagnella 30
Pozzobon 100
Tosi 100
Zucchetta 100
TOTALE 7.7 FTE
Percentuale CMS
Branca 100
Carlin 100
Checchia 100
Dosselli 90
Gasparini U. 100
Kanishcev (TN) 70
Lacaprara 100
Lazzizzera (TN) 70
Margoni 70
Meneguzzo 100
Pazzini 100
Ronchese 100
Simonetto 70
Torassa 100
Zotto 100
Zumerle 100
TOTALE 14.7 FTE
Percentuale CMS
Bellato 40
Benettoni 30
Gonella 80
Michelotto 20
Montecassiano 70
Passaseo 100
Pegoraro 70
Sgaravatto 70
Ventura 50
TOTALE 5.3 FTE
40
Richieste servizi
Richieste Servizi 2013
mesi/uomo Note
operatore per tests dei chips
5
tecnico in sede 6 di cui 3 m/u da D.Pantano
officina meccanica 1 Parti meccaniche: chip holder
Off. Elettronica:
12 m.u. test funzionale e di produzione TRB-theta e spare TRB-phi
4 m.u. Installazione nuove schede sul rivelatore
2 m.u. riparazione schede recuperate dal rivelatore
6 m.u. manutenzione camere durante LS1 & preparazione sist.test
minicrates
Off. Mecc. 2 m.u. attrezzi/supporti per test TRB
0,5 m.u. realizzazione secondo sistema portatile di test minicrates
Uff.Tecn. 1 m.u disegno attrezzi/supporti DT TRB tests
Serv. Calcolo : 24 m.u. Supporto cluster locale CMS, supporto CMS center,
maintenance/operations/sviluppi T2 Pd-Legnaro
Tracker:
DT:
41
Richieste finanziarie 2013
41
Richieste Finanziare 2013
Keuro Note
Missione Interne 7.7
Missioni Estere 136.4
5.9 m/u metabolismo
9 m/u responsabilita' tracker
9 m/u responsabilita' non tracker
9 m/u presa dati / servizi @Cern
3 m/u tecnici
Consumo 18.6
11.6Keuro metabolismo
4.0Keuro auto
3.0Keuro clear room
Totale 162.7
Richieste Finanziare 2013
Keuro Note
Missione Interne 20.0
Missioni Estere 273.6
13 m/u metabolismo
13 m/u responsabilita' DT
6 m/u responsabilita' non DT
20 m/u presa dati/servizi @Cern
20 m/u tecnici
Consumo 39.0
30 Keuro metabolismo
9.0Keuro auto
Totale 332.6
Tracker:
DT:
Dal Gennaio 2013: prossimo responsabile locale sara’ Paolo Checchia;
auguri a Paolo di buon lavoro: saranno anni impegnativi,
ma certamente di grande interesse…