OPERA experiment Commissione II INFN Perugia, 26 Settembre Maria Teresa Muciaccia MTMCommissione II INFN

Summary OPERA 2011 activity CNGS beam Detector and facilities status Emulsion development facility Improvements in the CS analysis Status of the data analysis OPERA Common funds MTMCommissione II INFN2

Unix time 2 E 13 pot/extraction Extraction 1 Extraction 2 5/9 7:00 Friday 18/3 19:00 Start of Run CNGS in dedicated mode (CNGS + LHC) since March 18 th until June 7 th (4 additional weeks due to North Area problems) Expected to run for 223 days (till November 20 th )  > 5 x pot Integral (2008  2011)   14.5 x pot  65% of 5 nominal years CNGS in 2011 MTM3 Commissione II INFN

Average efficiency for % MTM4Commissione II INFN

Unix time Start of the run 18/3 5/9 at 7: E 19 pot 5/9 7: on-time events 3947 interactions in target Technical stop MD Technical stop MTM5Commissione II INFN

CNGS beam performance YearBeam daysP.O.T. (10 19 ) Total MTMCommissione II INFN As of 5/9/ p.o.t. Days

Detector and facilities performance 7MTMCommissione II INFN

Improvements in the understanding of the electronic detector MTMCommissione II INFN8 µ momentum x charge Reconstructed energy for 1µ events Study for 1µ events New Journal of Physics 13 (2011)

extracted bricks (2008  2011) Brick manipulator system X-ray marking MTMCommissione II INFN

Target mass evolution 10 -5% Last BAM prod Black CS change MTMCommissione II INFN

Emulsion development facility MTMCommissione II INFN11

Development Team Local experts: Andrea Schembri, Lucio Di Paolo Trained operators: G.Di Silvestro, G.Mascioni, (A.Carbone (TC Service) contract expired in August ) INFN LNGS art.15 : A. Di Stefano, G. Moro INFN expert shifters : Bari (A.Andriani,P.Dipinto,V.Dipinto), Bologna (D.Di Ferdinando, E.Bottazzi,L.Degli Esposti,V.Togo,C.Valieri),Napoli (C.Cassese,Padova (M.Negrello) OPERA Shifters: LPI Moscow INFN Rome (maintenance): M.Capodiferro (dev lines), A.Ruggieri (DB) Weekly job (9 h/day five days) INFNTrained operators OPERA shifters CSD + 60 ECC MTM12Commissione II INFN

Emulsion Lab Status CS facilities 1) Chemicals preparation on-site (manual) 2) Films labeling manual 3) Development ( max 240 CSD /week or 120 CSD & 4 ECC/week ) Lab 1 1) Chemicals preparation on-site (semi-automatic) 2) Films labeling manual 3) Development ( max 100 ECC / week) Major improvements in the system to automatically set the temperature in the developer tanks (ready on one line by this month) MTM13Commissione II INFN

Development statistics Stop: (17 th Dec – 13 th Jan) Xmas (24 th Dec – 10 th Jan) August (1 week) Mean = 55 April 2010 – September Lab 1 Done: 3665 ECC with cosmic exposure  350 K films processed so far MTM14Commissione II INFN

Improvements in the Changeable Sheet analysis 15MTMCommissione II INFN

Scanning of Changeable Sheets: several tasks accomplished Nagoya: 5 S-UTS, 220 cm 2 /h LNGS: 11 microscopes, 220 cm 2 /h  ~2 µm So far  cm 2 analyzed 16MTMCommissione II INFN

17 CS analysis speed up CC event measurement likelihood to replace visual inspection Tracks validated through visual inspection Background tracks 40% of CC events validated without visual inspection since 2010 ratio 17 MTMCommissione II INFN

CS analysis Speed up the analysis of events without µ in the final state vertex pre-definition Transverse distance(projection) (µm) Longitudinal distance (µm) Neutrino interaction vertex rms = 0.3 mm rms = 3 mm Tracks in interface films 2mm 18MTMCommissione II INFN

Current status of the data analysis 19MTMCommissione II INFN

Performance plot, runs 3765 interactions located, 3289 “decay searched” events MTM20Commissione II INFN

Event location summary for 2008 run 0mu1muAll Events predicted by the electronic detector Found in CS Interactions located in ECC Located in dead material Interactions in the upstream brick2911 Decay search performed MTM21Commissione II INFN

Overall efficiency using 2008 run EventsAll0µ1µ Triggers Interactions in the bricks Reject bad quality films 0.94 Brick identification by electronic detectors Location fraction Located interactions % and 74% for 0µ and 1µ events 88% and 97% with 3 rd brick requests MTM22Commissione II INFN

2008 in Europe and Japan EuropeJapan 00 11 00 11 Events predicted Located interactions Ratio (%) 41     2.0 Good agreement for 0  events MTM23Commissione II INFN

2008/09 runs 0mu1muAll Events predicted by the electronic detector Interactions located in ECC EU JP Located in dead material Interactions in the upstream brick Decay search performed EU JP MTM24Commissione II INFN

Status of event location for 2010 run 0mu1muAll Events predicted by the electronic detector Extracted CS Interactions located in ECC Decay search MTM25Commissione II INFN

Improvements in the data analysis 26MTMCommissione II INFN

Full emulsion simulation OpEmurec code  Vertex position distribution within the brick: Located interactions for events without µ in the final state are compared with OpEmurec simulation 27MTMCommissione II INFN

Background reduction systematic track follow-up for muon detection 28MTMCommissione II INFN BG sources: Charm Hadronic interactions in µ CC with misidentified µ (  →h channel) Hadronic interactions in µ CC and NC (  →µ channel) Tested in the analysis of the first  candidate

Track follow-down analysis Interaction visible in the brick Momentum/range correlation L = track length R lead = µ range ρ average = average density along the path ρ lead = lead density p = momentum measured in emulsion Discriminating variable Hadrons and muon stopping in the brick Mis-ID muons in charm events 3.28% (was 5%) 2 orders of magnitude reduction of the  →µ background due to µ mis-match in CC and NC events 29MTMCommissione II INFN

Improved decay search procedure - search for decay topologies is a crucial task in OPERA - a systematic DECAY SEARCH (DS) procedure has been defined and applied over all the located events since December 2009 to detect all possible decay topologies (charm +  ) in the lead-emulsion target Main steps of DS : 1) improve the vertex definition (IP studies) 2) detect possible kink topologies on primary tracks (  RMS kink study) 3) search for extra-tracks from decays not attached to primary vertex (IP vs  z* selection)  z is defined for a volume track as the distance between the 1ry vertex z position and the one of the upward segment of the track MTM30Commissione II INFN

Decay Search in OPERA some improvements in the decay search come from the use of micro-tracks This led, as example, to fully discard penetrating tracks MTM31Commissione II INFN

Decay Search in OPERA tracks not related to the event may be discarded due to a  z selection cut kink topology detected by IP IP distribution of tracks associated to primary vertices MTM32Commissione II INFN

Results of the decay search: neutrino induced charmed hadron production Charm topology analogous to  (similar lifetime) D0  4 prong Charged charm  trident 33MTMCommissione II INFN

Charm events as a control sample (data versus MC) 2008/2009 runs TopologyObserved eventsExpected events CharmBackgroundTotal Charged 1-prong Neutral 2-prong Charged 3-prong Neutral 4-prong32.0< Total3939.1±7.53.0± ±8.3 Decay length of charmed particles , angle between the charmed particle and the primary µ in the transverse plane 34MTMCommissione II INFN

Kinematical criteria for tau hunting in OPERA Tau  h - p h > 2 GeV/c (low energy hadrons from  CC) - decay vertex p t > 600 MeV/c (p t > 300 MeV/c if gamma pointing to the vtx) - missing transverse momentum at 1ry vtx p tmiss < 1 GeV/c -  >  /2 Tau  e - E e- > 1 GeV (low energy  ) - E e- < 15 GeV (prompt e- from e CC) - decay vertex p t > 100 MeV/c ( e CC) Tau  mu - E m > 1 GeV (low momentum  mis-ID) - E m < 15 GeV (  CC) - decay vertex p t > 250 MeV/c MTM35Commissione II INFN

VariableValue kink (mrad)41 ± 2 decay length (µm)1335 ± 35 P daughter (GeV/c) Pt (MeV/c) missing Pt (MeV/c) ϕ (deg) 173 ± 2 Detection of the first  candidate event PLB691 (2010) MTMCommissione II INFN

Signal events One  candidate observed in the  → h channel where 0.49±0.12 events are expected with a background of 0.05±0.01 event The probability for the event not to be due to a background fluctuations is 95% MTMCommissione II INFN37 Decay channel Number of signal events expected for 22.5×10 19 p.o.t. Analysed sample (run 08/09)  → µ  → e  → h  → 3h Total

Interesting by-product of the analysis chain: detection of e in muonless events September events in the analyzed sample µ → e analysis ongoing 38MTMCommissione II INFN

Peculiar topologies LabEvents Located Decay search (CC) Charm Candidates e candi dates  candidates Total MTM39Commissione II INFN September 2011

OPERA Common Funds MTMCommissione II INFN40

Spese sui CF Principio generale: – I CF coprono le spese ordinarie di run dell’esperimento – Le manutenzioni ordinarie dei sottorivelatori sono a carico delle Funding Agencies responsabili della loro costruzione (MoU) – Interventi straordinari (emergenze, overcost imprevisti etc.) sono discussi nel Coll.Board e, se impattano sui CF, vanno ratificate dal Financial Board Peculiarita’: – OPERA ha 5 facility accessorie che richiedono soprattutto personale a basso (operatori) o alto (ingegneri) grado di specializzazione – Lo scanning dei brick non e’ incluso (“analisi dati”) CS scanning stations Japan LNGS Robots BMS Brick handlingSviluppo emulsioni MTM41Commissione II INFN

MTMCommissione II INFN42 Policy for contributions to shifts and common fund adopted by the CB for 2010 and following The formal composition of a group is fixed at the beginning of each civil year by the group leader and endorsed by the CB. Nominal shares are proportional to the number of scientists in the group, including PhD students. A group must contribute to at least 35% of its nominal contribution to the common fund in cash or in-kind for the equivalent amount (and depending on needs). The group compensates for the missing contribution to the common fund with shifts in extra to its nominal share. Policy for being by default signee of physics papers: be a formal member of a group during the civil year and effectively contributing to the experiment for at least one year or having be a formal member of a group during the preceding civil year and having stopped effectively contributing to the experiment for at most one year.

Difficolta’ avute in passato Common Fund non discussi al tempo del MoU (2001) [comprensibilmente: priorita’ sul resharing dei costi dopo la prima crisi finanziaria CERN e la corrispondente chiusura di CERN-OPERA] Nel 2006 gravi difficolta’ con il Giappone: il MEXT non approva l’ultima tranche di emulsioni di OPERA (25%!); KEK e Nagoya Univ. coprono gli impegni gia’ presi con la Fuji interrompendo ulteriori finanziamenti al gruppo di Nagoya Definizione dei common fund fatti nel 2007 a livello di Coll.Board e endorsed dalle principali Funding agencies: Belgio, Francia, Germania, Giappone, Italia, Svizzera ma – Sostanziale impossibilita’ del gruppo giapponese di contribuire dopo il mancato finanziamento MEXT – Mancata stima del costo dello scanning CS di Nagoya (Giappone appare piu’ insolvente di quanto e’ effettivamente) – Nessun contributo dalle istituzioni russe (19% del totale) Molti passi in avanti, soprattutto nel 2009: contributo Giapponese ragionevole, istituzione di un Financial Board regolare, pressione per contributi in-kind degli istituti insolventi MTM43Commissione II INFN

Dove si puo’ risparmiare? Sugli operatori: lavorando sull’automazione dello facility accessorie incrementando i turnisti OPERA ottimizzando i turni brick handl. & BMS MTM44Commissione II INFN

Sharing dei costi Belgio, Francia, Germania, Italia, Svizzera OK Giappone: parzialmente insolvente (al livello del 35%) [run della stazione di scanning dei CS a Nagoya e acquisto parziale di prodotti chimici per lo sviluppo e altro materiale di consumo] : sharing tra Belgio, Francia, Germania, Giappone, Italia, Svizzera (75% dei firmatari). 2010: cerchiamo di spingere per una piu’ equa ripartizione 35% del dovuto per Russia, Turchia, Croazia e Tunisia: (~80 kE) escludere istituzioni e firmatari che non hanno contribuito a livello sostanziale oltre che di sharing dei fondi (~20 persone) Recuperare il 35% mancante giapponese incrementando la loro presenza al Gran Sasso (in-kind) MTM45Commissione II INFN

Previsioni I costi di run di OPERA sono dominati dalle facility accessorie e ci sono margini di miglioramento (15-20%) Il carico di turni/firmatario e’ molto pesante in Opera (circa 5 settimane per firmatario) percio’ eliminare firmatari sulla base dell’insolvenza dei CF puo’ rivelarsi un boomerang per la collaborazione. Vanno cercati compromessi ragionevoli: in questa linea si sta muovendo il Coll.Board In-kind: e’ lo strumento che finora ha dato migliori risultati: chi non puo’ pagare contribuisce ai turni se ha modo di inviare persone a costo piu’ basso (Russia, Turchia). Tuttavia, non e’ realistico che le istituzioni insolventi coprano tutto il contributo CF in-kind (inviare gente al GS e’ comunque costoso) Nei limiti delle nostre capacita’ di previsione, nei prossimi 2-3 anni il carico sull’INFN rimarra’ dell’ordine di 450 kE con possibili miglioramenti: Diretti: aumento del contributo giapponese e russo via cash o in-kind Indiretti: riduzione del numero di turni per firmatario per contributo non-europeo o per ottimizzazione delle facility MTM46Commissione II INFN

47 With the adopted change: INR from 8 to 6 memberships (as agreed within RC, Chair-CB, SP and INR-Olga) 2011 CountryMemberRequest2010 ResGrantSp. homeat LNGSat AC Italy 52,5488,15,5460, Switzerland 15139,5-9,0148, France 15,5144,11,7142, Germany 883,783,483.4 Belgium 218,60,218,318.3 Japan 28154,2+eS100, Korea 59,7+eS JINR 716,6+eS0,116,316.3 Croatia 427,013,5 ? Turkey 49,5+eS0,19,4 ?9.4 MSU+LPU 5+523,8+eS16,7 INR 614,2+eS0 ITEP 24,7+eS0 Israel 1 6, (res. 10)-24.7(10) TOTAL ,3991, New: OK ! MTMCommissione II INFN

Summary and estimattion for 2012 The year 2009 has been very difficult to be handled: The initial quote corresponded to the formal sharing for membership There was extraordinary contribution by INFN (50 K€) and others F.A. Plus many small contributions by single (italian) groups In 2010 a new way to share the costs: 35% cash+Extra-shifts for 50% groups Corresponding proportional increase of cash for the others 50% groups Good response in getting cash for the FIRST time by some groups, but not all Other way of pressure applied: reduce membership In 2011 the situation is going worse: less money from “35%” groups Other way of pressure rejected by the OPERA Coll.Board In 2012 go back to formal membership sharing ? Foreseen 488 K€ (or 355 K€) Luca Stanco (september 2011) MTM48Commissione II INFN

Conclusions CNGS is performing well for the 2011 run. Chance to go beyond the CNGS nominal year (4.5 x pot) Improving performance of the OPERA detector and of its ancillary facilities Analysis of the 2008/09 data sample: better knowledge of experimental features, background and efficiencies. Several notable improvements One  candidate observed with a significance of 95% in the hadronic channel. In progress other possible candidates. In parallel: scanning and analysis of 2010 and 2011 in progress Working on µ → e search. Exploit the peculiar capabilities of OPERA in identifying electrons. Aim at contributing soon to the international effort Surprising results in the measurement of the neutrino velocity But big problems on the man-power and financial side Thanks to the Commissione II for the constant support 49MTMCommissione II INFN