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Explore the search for elusive "Black Swans" in neutrino physics through a community collaboration effort led by the NESSiE Collaboration. This meeting, led by Luca Stanco, delves into the potential existence of multiple neutrino species and the challenges in risk analysis within the field. Discussions cover the necessity of spectrometers for Short and Long Baseline experiments, emphasizing CP violation, R&D programs, and the potential for an SBL program. The NESSiE Initial Design highlights the essential components of Iron spectrometers to advance neutrino research. Additionally, new strategies, scenarios, and R&D priorities are proposed for high-priority large-scale scientific activities endorsed by CERN, with a focus on nm disappearance searches and innovative methods for oscillation extraction. The meeting aims to address key physics goals and innovative approaches to further the understanding of neutrinos.
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CERN restrict meeting, November 26th 2013 Luca Stanco for the NESSiE Collaboration NESSiE Collaboration (Neutrino Experiment with SpectrometerS in Europe) • Currently the following Institutions are members of NESSiE: • 6 italian groups: Bari, Bologna,Frascati, Lecce, Padova, Roma1 • 2 russian groups: SINP-MSU, Lebedev-LPI • 1 Zagreb (Croatia) • Around 65 physicists plus engineers and technicians • Observers: • Strasbourg (France) • Hamburg (Germany) • Napoli (Itay) All these groups have long experience in Neutrino Physics and Hardware (Chorus, Macro, Nomad, Opera, T2K …)
On the quest for the BLACK SWANs if you did not see ever any black swan, does it mean that they do not exist ? Taleb Nassim, “The Black Swan”, 2007 Ex-statistician, now a very rich person, by applying his theory of Risk Analysis to Financial World
In Neutrino Physics we may face a more complicate version: in case they exist, is there more than one species ? • And our community own several opinions: • Only one type of Black Swan exists • Looking for more is equivalent to suspect that Flying Donkeysexist even if anybody never saw • How to look for them ? with this ? or like that ?
In any case, everybody knows that Risk-Analysis is a touchy and subtle operation. Pay attention to avoid this situation or Looking in the wrong direction Looking all in the same direction
Some facts: • Leptonic Flavor investigation should be a MUST for the HEP future • CPV is “in our hands” given the ”large” value of q13 • It may be a long shot, and it might be difficult to have more than ONE Big Project • Contemporary R&D and even other Physics programs are mandatory • An SBL program may be a good possibility, with measurements of - ne/nm appearance/disappearance and neutrino cross-sections • Under Gran Sasso there are equipments 10 M€ valued to be perfectly usable, with a relative modest investment, for Spectrometers • Spectrometers at a neutrino beam. Extended studies: • SPSC-P-343, arXiv:1111.2242 • SPSC-P347, arXiv:1203.3432 • ESPP, arXiv:1208.0862 • LOI CENF:https://edms.cern.ch/nav/P:CERN-0000096725:V0/P:CERN-0000096728:V0/TAB3 • L. Stanco et al., AHEP 2013 (2013) ID 948626,arXiv:1306.3455v2 Note: increasing consensus in the Community that Spectrometer(s) are needed either for SBL or LBL
NESSiE Initial Design ICM • Two Iron spectrometers (ICM), 1500 + 800 t, composed by: • 48 yoke blocks, , 4.5 x 0.6 x 1 m, 25t • 480 slabs, 2 – 3 t, 1.25m x 3.5–6 m • 1800 + 700 m2 of RPC • «sandwich style» assembly to be made in situ, one piece per time • 20,000+12,000 digital channels • Two ACM preassembled andinstalled in one shot • Precision Trackers preassembled and installed in one shot • Near Nessie movable aside on air-pad • 1 + 0.5 MW , 10 kA, power(summed up for ACM and ICM) ACM n Optimized ! Reduced by about a factor of 2 !!!
Another fact: Following the outcome of the European Strategy Group, CERN committed us to start an R&D program for Neutrino Physics, in sinergy with LBL (USA or Japan), while waiting for a granted SBL beam Excerpt from ESPP CERN strategy, final document approved on May 7 2013, Endorsed by CERN Council at the end of June.: High-priority large-scale scientific activities: (c-d-e-f)
(from recent P5 DG presentation) CENF/CERN WA104 (NESSiE) NeDe/LBNE SBL/FNAL
Which scenarios ? • Use OPERA Spectrometers to explore 1-2 orders of magnitude innmdisappearance(Need CENF-like nm beam, or new tunnels/caverns in NuMI) • Use NESSiE-original (ICM+ACM) plus a target (LAr or Scintillators)to also measure NC, and cross-sections(Need CENF-like nm beam for PhysicsEnough FNAL Booster just for cross-sections) • Use large-ACM superconducting in LAr (5x3x2) to couple ACM and target.ICM also present, for Physics. How much R&D ?(Need Charged Beams, nm beams for Physics as in (2)) • Use LAr tank of order 100 ton, with magnetized SC-ACM, and/or ACM-saPrototype useful for one of the LNBE-Nears(Need Charged Beams, need CENF-like nm beam and T600 for Physics)
Scenario (1) SBL nm disappearance search(*) • - Focus the physics goal to gain an order of magnitude in nm disappearance limit at eV scale for Dm2 • Set the issue of using only iron magnets, with a small scintillator target to measure NC • Define a way to extract oscillation by using a new variable (*)LS et al.: AHEP 2013 (2013) ID 948626, arXiv:1306.3455v2. 10
SPECTROMETERS ONLY… nm beam Double ratio (F/N)data / (F/N)no-osci anti-nm beam Non oscillation hypothesis is tested with a c2 test to a flat (= 1) distribution New variable: log10(1/E) 11
Part of Scenario (2) http://arxiv.org/pdf/1311.4750.pdf T2K, end 2012, ND, data vs Simulation, http://arxiv.org/pdf/1211.0469.pdf
Conductor: Al Coil Cross Section 72x72 mm2 Hole (cooling) = 30 mmØ B=0.12T Compare e.g. with ISS-Detectors, http://arxiv.org/pdf/0712.4129v1.pdf 14
Sensitivities for the present NESSiE configuration (full simulation, with neutrino beam) Charge ID Best, ever, sensitivity for m detection with similar apparata over large area (and few MCHF cost) (goal ≥ 250 MeV) Momentum Momentum measured by range (ICM) up to 3.5 GeV, then ACM and ICM provide ≈30% (goal ≥ 250 MeV)
However recent developments on SuperConducting cables or even the use of SC coils à la ATLAS allow us to think to a different approach in magnetization. R&D on magnetization of LAr tank: Pros: - best detector for both muons and electrons - similar Near and Far detector sites for the LBNE project - couple ACM with target Cons: - structural forces (depending of the magnetic field) - insulation structures - cost ? - long way ?
R&D planning: 1) Prototype ACM-warm (conditionally funded by INFN) 2) Tracking Detectors in Magnetic Field R&D 3) Evaluation ACM-cold 4) Collaboration with LAr activities/groups
CONCLUSION/VISION • Neutrino Physics is a MUST for Particle Physics • (neutrino mass, Majorana/Fermi, astroparticle connection, window for BSM) • CERN/Europe should be a MAJOR actor • (facilities, past experience, major partner in the Global picture) • Large and experienced community • (knowledge, motivation, largeness) • A Global Coherent Strategy is MANDATORY • (increasing bigness of the experiments) • Prioritization or Compromise ? • (multi-year projects, limited resources) In our case bad luck will correspond to bad planning
Fringe Magnetic Field upstream the ACM – No shielding B (Gauss) 22 Gauss z (beam axis, m) LAr ACM (z = - 3.5 m) 10
Fringe Magnetic Field upstream the ACM – With shielding 0.7 Gauss B (Gauss) z (beam axis, m) LAr ACM (z = - 3.5 m) 11
Shielding 2 iron slabs (5 cm thick) 1 Vacoflux-50 slab (1 cm thick) Vacoflux = Colbalt-Iron Alloy with maximum saturation at 2.35 T y z 12
New configuration (to be optimized) Iron Core Magnet => 1 higher iron slab (50 cm thick) y z y (m) 13
New configuration (to be optimized) Iron Core Magnet => 1 higher iron slab (50 cm thick) z (beam axis, m) LAr ACM (z = - 3.5 m) 14
Power/Spending review In the first design the power consuption was PNEAR = 600 kW PFAR = 1630 kW The design was optimized in order to reduce the power consuption but keeping the required muon charge ID Full cross section = 72 x 72 mm2 Cooling hole f = 30 mm => Conductor cross-section S = 4477 mm2 Coil length L = 17.2 m Coil number N = 39 rAl = 0.027 W mm2 / m I =8100 A => B = 0.12 T PNEAR = N I2rAl L /S = 270 kW ( PFAR = 760 kW ) NESSiE – WA104 16
OPERA re-use (under pressure of SPSC and INFN) • 2 Spectrometers “available”, with Detectors and Servicing • Possibility to full re-use for Far AND Near ICM • Need two new sets of Yokes (Top & Bottom) new Electronics for RPC Mechanical Tools PT detectors • Scintillators • Other: ACMs Under discussion in OPERA: possible start dismantling begin 2015
MONEY estimation and Opera endowment (dismantling in 2015) Iron magnets: in-kind value 5940 K€ (from OPERA MoU) Cost for transportation to CERN and refurbishing: 3000 K€ In-kind value of Precision Tracker: 1900 K€ possible refurbishing: 700 K€ In-kind value of Scintillators: 1900 K€ possible refurbishing: 300 K€ Cost ACM: 1000 (Near) + 1200 (Far) TOTAL: 3+1+1+1 = 6 M€ ACM-NEAR, including R&D, designs, certifications ACM-FAR might be staged at 2nd phase (after LS2) 28
Top view Side view
FNAL options under investigation Booster Beam (at 700 m) (realistic simulation with fluxes, cross-sections, GEANI 2.6)
Muon momentum distributionPositive polarity (compare all) • The spectrum at FNAL is softer than CERN but the rate including the numi off-axis are comparable. • In positive polarity the anti-nu from from defocused mesons are small • The various component test different L/E
New Beam for LBNE (at 700 m) (fluxes comparison, to be evaluated for the LBL-Near Detector)