CNGS neutrino beam - MODULAr project

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measurements from ICARUS-T6 to MODULAR LAr-TPC CNGS neutrino

1 Alberto Guglielmi Istituto Nazionale di Fisica Nucleare, Sezione di Padova CNGS neutrino beam - MODULAr project toward, measurements from ICARUS-T6 to MODULAR LAr-TPC CNGS neutrino beam: present and perspectives Otranto, September A. Guglielmi, NOW8 1

2 neutrino oscillations strong evidence for neutrino flavor changing transitions existence of a mass term cosmological arguments: oscillations: and an interaction violating lepton flavor number to build up the today s dominance of matter over antimatter in non-equilibrium conditions a strong violation in the quarks must be extended also to leptons neutrino oscillations have been observed in the solar and atmospheric s, the corresponding parameters, and, have been measured - a third subleading oscillationshas not been detected yet: a CP violation phase driven by : mixing angle - link between solar/atmosph., will allow the ordering of masses and the determination of!! $ - present limit #at 9 % C.L. &% ev (Chooz) ' hard to be measured in a beam: % effect at the appearance maximum! - Double Chooz, Reno, Daya-Bay reactor experiments: addressed to explore down to.1 A. Guglielmi, NOW8 2

3 9 3 / 21 first generation long baseline (present beams: intrinsic (-Factories: T2K: present SK detector but a new.7 GeV 8 $ $ ) * 3! $A -.,? (oscillations at accelerators: toward + and /experiments: K2K over km baseline, NuMI and CNGS with km with conventional beams, 17 KWatt on target present detectors: SK 22.5 kt W-Cherenkov, MINOS 5.4 kt Iron-Scintillator calorimeter and ICARUS t liquid Argon TPC (LAr-TPC) OPERA emulsion detector for 4 appearance., measurement in ' requires major improvements both in beams and detectors: high intensity pure 576/beams, tuned to, well defined energy spectrum contamination mainly from and K decay) 8 - s from decay of accelerated s - -Beams: s from decay of accelerated radioactive ions, just one flavor beam! ultimate massive detectors, able to measure -CC (i.e. electrons!) rejecting -NC (i.e. :< s) - 1 kt LAr-TPC (GLACIER), 5 kt L-Scint. (LENA), kt W-Cherenkov (MEMPHIS) - USA and Japan: two similar projects (UNO and HypeK) <=> generation experiments at improved conventional beams, 1 MW power and even beyond: /beam from 5 GeV/c RCS,.7 MW, $km NOVA project, 2 kt L-Scint. km, 2 GeV beam, pot/y at 12 GeV/c. A. Guglielmi, NOW8 3

4 A. Guglielmi, NOW8 4

5 the MODULAr proposal is focused on the following three main items/activities: for B -decay and cosmic a new LAr-TPC Imaging underground detector made of several identical units, each of fiducial mass devoted to physics with and without accelerators, search for proton-decay. First step: 2 kt LAr-TPC detector to be realized along the lines of the vast R&D work carried out the last decades by the ICARUS Collaboration. The imminent start of data taking with ICARUS-T6 detector at LNGS Hall B represents a milestone for large LAr-TPC technology! a new experimental area LNGS-B tailored to MODULAr detector, eventually enlarged in future phases, 1 km Off-Axis from the main laboratory, away from the protected area $kt of Gran Sasso National Park at 1.2 km of equivalent water depth: the superb event imaging power of LAr-TPC will ensure a very efficient reduction of c-ray induced background s from CNGS but also for searches. a new neutrino beam derived from the existing CNGS facility, the proton beam line from the 4 GeV/c SPS, eventually with an increased intensity relatively modest changes in the energy range for searches beam focusing of CERN will produce a nearly optimal beam in few GeV A. Guglielmi, NOW8 5

6 LNGS Hall B: 6 t LAr-TPC solar, atmosph., SNovae s CNGS s p-decay LAr filling: middle of October the detector is expected to operate soon after with c-rays and CNGS beam s A. Guglielmi, NOW8 6

sensitive, self triggering - high granularity ( mm) - excellent calorimetric properties - particle

7 5 C6 ICARUS-T6: an Electronic Bubble Chamber LAr-TPC [C. Rubbia: CERN-EP/77-8 (1977)] 3D imaging of any ionizing event with in addition: - continuously sensitive, self triggering - high granularity ( mm) - excellent calorimetric properties - particle identification ( DCvs. range) After many years of R & D at lab scale... the road for construction of VERY MASSIVE LAr TPC detectors is now open! A. Guglielmi, NOW8 7

$limited by NC background: # %, NC indistiguishable from in a sizeable fraction of$ events 5 % w.r.t. intrinsic beam contamination! detection eff.

8 E G F H event observation: LAr-TPC imaging capability detection in L-Scint/W-Cherenkov limited by NC background: # %, NC indistiguishable from in a sizeable fraction of events 5 % w.r.t. intrinsic beam contamination! detection eff. NOVA: increase of backg by A. Guglielmi, NOW8 interactions! : I moreover: E ( ( key of ( LAr-TPC: a detector for 8

KL Q R P 5 C6 J NC : background in LAr suppressed by: topology ( conversion from vertex) reconstruction of : mass electron/photon separation based on DCdifference Residual

9 KL Q R P 5 C6 J NC : background in LAr suppressed by: topology ( conversion from vertex) reconstruction of : mass electron/photon separation based on DCdifference Residual misidentification Electron identification eff.o NM% L% much higher discovery potential of LAr than L-Scint./W-Cherenkov detectors: 5 kton LAr detector Lkton of L-Scint! A. Guglielmi, NOW8 9

10 @A MODULAR detector: from ICARUS-T6 to multi-kton LAr detector by a modular approach! MODULAr will be initially composed by 4 identical modules,2 kt LAr, allocated in the shallow-depth new cavern each section and about 6 m length LAr active mass: 537 ton 4 m electron drift 3-D imaging similar to T6 but 6 mm pitch A. Guglielmi, NOW8 1

refrigeration well established/tested wiring technique used for T6, but wire length purity : air Sppm, H.V.: -2 kv cathode biased ( VXWU $kv/cm) 8 PMT s + Wl.s. for prompt (ns) VUV scintillation light, up to 2 % of Q.

11 @A T> 6! 2 The MODULAr detector inherits all the achievements of ICARUS-T6 mechanical structure: external insulating vessel, a linear supporting and holding structure, LAr an N2 supply and refrigeration well established/tested wiring technique used for T6, but wire length purity : air Sppm, H.V.: -2 kv cathode biased ( VXWU $kv/cm) 8 PMT s + Wl.s. for prompt (ns) VUV scintillation light, up to 2 % of Q.E. electronics for 1 module: 5 channels, new improved design (same T6 front-end can be used!) MODULAR: ICARUS-T6 scaled-up by 2.66! m limited R&D:SLICE MODULAr section but only 4 m long air evacuation by flushing pure Argon gas insulation by expanded perlite 4 m electron drift A. Guglielmi, NOW8 11

$ a new LNGS Lab new experimental hall shallow-depth m, present LNGS halls: 18 m two sites proposed OUT-of- Parco Naturale del Gran Sasso and FAR from high-way (NO special safety/environmental

12 $ a new LNGS Lab new experimental hall shallow-depth m, present LNGS halls: 18 m two sites proposed OUT-of- Parco Naturale del Gran Sasso and FAR from high-way (NO special safety/environmental limitations!) 1 km Off-Axis w.r.t. present CNGS beam axis site A in Aquilano (Teramo side): preferred site B in Camarda (L Aquila side) both below 1.2 km eq. water. depth preliminary studies: good rock, no water! A. Guglielmi, NOW8 12

13 6! $ Y new CNGS off-axis neutrino beam facility 2!! A!! A Z 6 6 [ 3! $A 732 km CERN-LNGS baseline: atmosph. oscillation max at6 (NOVA project: similar baseline and GeV: $GeV energy) CC at 12 GeV (FNAL) and 4 GeV (CNGS), same low cross-section and energy focusing optics, 732 km, -interactions are perfectly reconstructed in LAr-TPC 14.8 mrad off-axis (no oscillations) CNGS beam Off-Axis configuration: no major increases of present SPS performance, 512 kw beam power at 4 GeV: pot/y a new target /optics design optimized for low energy, 1 km Off-Axis neutrino beam proton energy: 4 GeV 2A12 GeV (NOVA) meson production scales almost linearly with, what matters is beam power: 512 kw (CNGS) vs. 768 kw (NOVA), not proton on target MODULAr (CNGS, 4 GeV) with pot/y NOVA (NUMI, 12 GeV) with pot/y! A. Guglielmi, NOW8 13

$Q N ` _ ] G\F$ present CNGS

14 Q N ` _ ] G\F appearance: ^ ( ( present CNGS neutrino beam line for 23/6/3 16/3/4 2/9/3 2 fast extractions at 4 GeV/c ba#! protons every 6s pot/year shared (dedicated) operations c a 3 $!1 #! A. Guglielmi, NOW8 14 GeV

15 op qsr lower :6 d v u x t * w ef g hi * j a new CNGS Off-Axis beam Off-Axis angle... similarly for n-decay k<l m l : j B increase of the flux at low energies which are the most sensitive to the resulting beam is essentially from : narrow, better known spectrum, contamination ( 8 and n3-body decay...) emission angle vs. momentum for mesons produced in 1 m long C vyx z x{ } x tv~ { target by 4 GeV/c protons Beam optics should focus low energy :: larger acceptance than CNGS high energy beam... target: 1 m long graphite, no spaces horn: at 2 cm from the target - NUMI-ME-like (3m long) - 2 ka current reflector: same position, outer dimensions as CNGS - inner conductor redesigned for 15 GeV focus, - 2 ka current A. Guglielmi, NOW8 15

16 ƒ ˆ! Y Œ Off-axis neutrino beam: Sensitivity vs. Off-axis distance 2 kt LAr detector pot/y 5 years data taking!, signal accept. 9 % r = s/sqrt(b) 5 figure of merit of the Off-Axis distance: 4 S = Signal/ Š Ž 3 2 maximum in range km distance Off-Axis (km) A. Guglielmi, NOW8 16

17 ! #A! A!# 2 A $A c proton beam power, p.o.t., events and discovery potential present CNGS intensity: pot/pulse, 6 s period, pot/y BUT: - shared mode (fixed target experiments) - assumed 55 % efficiency for accelerator complex operation order pot/y achievable without major upgrades ( pot/y for 2 days full efficiency dedicated operation) - rates in MODULAr proposal calculated for pot/y Further intensity upgrades of CNGS beam envisaged by increasing proton beam intensity delivered to CNGS by PS/SPS complex (up to pot/y) undergoing investigation to support 1.6 MW proton target 1!- present target: designed for!#p/pulse a nominal) - new target: increase of the thickness and beam spot widening will improve resistance - Horn heating: dominated by the current, not by the beam - Ventilation? equipments are now well shielded in the auxiliary tunnel, not in the beam chamber -... A. Guglielmi, NOW8 17

18 -beam,6! 5 4 j : n j allows for a precise combined measurement of incoming s - modulo MODULAR: a two FAR detector experiment Monte Carlo calculations: within few % systematics and, $% (benchmark: NOMAD data of WANF beam of CERN SPS) the simultaneous use of two FAR detectors - ICARUS-T6 On-Axis and MODULAr Off-Axis - - cross-sections: the two FAR detectors see the target/beam-optics within same small angular acceptance (not in the case of conventional NEAR-FAR detector experiments) Off-Axis precise measurement of On-Axis -beam -6 $GeV: 1GeVmuch less sensitive to correction for ν µ fluence (a.u.) : of incoming measurement flux after driven oscillations Neutrino energy (GeV) ν µ fluence (a.u.) Neutrino energy (GeV) On, Off -Axis transformation is then straightforward: in the two body A. Guglielmi, NOW8 18 lower energy Off-Axis the beam is an effect of well-known Jacobian-peak decay kinematics

19 6 n j 8 Y : j j Off-Axis contamination: from measurement of On-Axis ( GeV: ) and Off-Axis ( GeV: ) A. Guglielmi, NOW8 19

20 ! $A!# 2 A! A ) * -., MODULAr sensitivity to + and - 2kt, 5 years CNGS-1: pot/y CNGS-2: pot/y ev 6 normal mass hierarchy GLoBES calculation: 5 % beam systematics 576!! A $ CC bg signal Š 5 Ž Rates for 2 kt mass, 5 y and pot/y, MODULAr NO A A. Guglielmi, NOW8 2 T2K

21 ^ _ Q N M Summary (beam: sensitivity on u R ), * Q LN The experimental results of recent years have profoundly changed the pattern of neutrino physics and our knowledge of the nature. And very likely, this is only a beginning... The exploration of CP violation in the leptonic sector requires the precise measurement of mixing angle in the ' subleading oscillations new MW proton drivers for low energy/high intensity neutrino beams are required T2K experiment at J-PARK,.7 GeV to SK W-Cherenkov: start in 29 from 5 GeV/c -.7 MW proton beam new detectors, higher NC/CC rejection capability & larger mass are needed: Liquid Argon TPC technique superior by a large factor w.r.t. W-Cherenkov, L-Scint MODULAr project at Gran Sasso: 2 kt - 4 modules LAr detector exposed to a new CNGS low-energy Off-Axis + up to T2K! MODULAr will be the status of art detector for the next with šgev one-flavor -beam from CERN as via ionization cooling! -. search A. Guglielmi, NOW8 21

22 BACK-UP A. Guglielmi, NOW8 22

23 n j : n j j 4 : j : j Y GeV dominated by the measured On-Axis:, production at target with syst. error from oscillation ν µ energy (GeV) ν µ energy (GeV) knowledge % accounts for 9 % Off-Axis, and 1 1 it s a direct measurement of intrinsic background generated by 8 (6 % of total) Off-Axis π + energy (GeV) π + energy (GeV) Moreover the Off-Axis spectrum above 1 GeV - totally insensitive to - exhibits a peak free from contribution:direct measurement of Off-Axis intrinsic background generated by (24 % of total) A. Guglielmi, NOW8 23

24 @A SLICE: a benchmark step toward slice of MODULAr, 4 m depht, total LAr active mass: 36 tmass of one half ICARUS T6 TPC chambers: central cathode, 2 pairs of 3 wire plane chambers with 6 mm sampling pitch 77 read-out channels, the present ICARUS-T6 DAQ design could be used as it is nominal electric drift field: 5 V/cm as in ICARUS-T6 (HV: 2 kv) PMT s coated with TPB wavelenght shifter, behind the read-out wires to provide a signal trigger and timing test of cryogenics, new insulation system (expanded perlite) new recirculation system filling method with initial air evacuation by flushing GAr improved electronics A. Guglielmi, NOW8 24

25 3A 3A DOUBLE-LAr at FNAL-Booster/CERN-PS : not only a test! 2 LAr detectors for a powerful reduction of the beam associated systematics: - a 1 t reduced SLICE module, 1 m from target - 2 SLICE modules, 5 t fid. mass, 44 m away œ CC for search for sterile ( s pot: powerful test of LAr NC rejection cross-section measurements A. Guglielmi, NOW8 25

ICARUS T600 experiment: latest results and perspectives

ICARUS T600 experiment: latest results and perspectives Marta Torti University of Pavia, INFN Pavia NBIA Ph.D School: Neutrinos underground & in the heavens ICARUS T600 at LNGS The ICARUS T600 detector