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Studying Nuclear Effects and Structure Functions at the NuMI Facility Jorge G. Morfín Fermilab NuFact’02 London, July 2002

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Jorge G. Morfín - NuFact02 - London, July What are these Nuclear Effects? F 2 / nucleon within a nucleus changes as a function of A. Nuclear effects measured (with high statistics) in -A not in From low-to-high x Bj go through: shadowing, anti-shadowing, “EMC” effect, Fermi motion.

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Jorge G. Morfín - NuFact02 - London, July Are Nuclear Effects the SAME for and e/ Scattering Shadowing with NOT the same as with charged leptons. t Axial vector component of current t Shadowing off valance quarks different than off sea quarks???? Shadowing separate phenomena from nucleus, has to be put in “by hand”. All such IVB effects are contained in nuclear parton distribution functions (Kumano, Eskola et al.) for parton level interactions. EMC effect can be accounted for in nuclear spectral functions.

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Jorge G. Morfín - NuFact02 - London, July Any Indication of a Difference in Nuclear Effects of Valence and Sea Quarks? Nuclear effects similar in Drell- Yan and DIS for x < 0.1. Then no “anti-shadowing” in D-Y a while “anti-shadowing” seen in DIS (5-8% effect in NMC). Indication of difference in nuclear effects between valence & sea quarks? a hep-ex/

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Jorge G. Morfín - NuFact02 - London, July Nuclear Parton Distribution Functions This quantified by : t K.J. Eskola b et al within LO DGLAP using initial nuclear distributions from CTEQ4L and GRV-LO and assume scale evolution of nuclear parton densities is perturbative. t S. Kumano et al c hep-ph/ plus a talk at this workshop Neutrinos have the ability to directly resolve flavor of the nucleon’s constituents: interacts with d, s, u, and c while interacts with u, c, d and s. b hep-ph/ c hep-ph/

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Jorge G. Morfín - NuFact02 - London, July A Specific Look at Scattering Nuclear Effects Q 2 = 5 GeV 2 S.A.Kulagin has calculated shadowing for F 2 and xF 3 in -A interactions based on a non-perturbative parton model. Shadowing in the low Q 2 (A/VMD dominance) region is much stronger than at higher Q 2.

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Jorge G. Morfín - NuFact02 - London, July Scattering Nuclear Effects compared to e/ Scattering hep-ph/

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Jorge G. Morfín - NuFact02 - London, July Goals in Study of Nuclear Effects with scattering Overall Goal: Measure nuclear effects across full x Bj range in scattering off a variety of targets. Goal: Measure nuclear effects separately for F 2 and xF 3. What are the nuclear effects for valence quarks alone ? Use as input to global nuclear PDF’s Long-term Goal: High statistics scattering experiment on H 2 and D 2 as well as heavy nuclei to extract all six structure functions on nucleons as well as within nuclei.

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Jorge G. Morfín - NuFact02 - London, July Fermilab On-site Beam and Near Detector Hall Target-Horn Chase: 2 parabolic horns. 50 m Decay Region: 1m radius decay pipe.675 m Hadron Absorber: Steel with Al core 5 m Muon range-out: dolomite (rock). 240 m Near Detector Hall 45 m

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Jorge G. Morfín - NuFact02 - London, July Neutrino Event Energy Distributions and Statistics Reasonably expect 2.5 x pot per year of NuMI running. le-configuration: Events- E peak = 3.0 GeV, = 10.2 GeV, rate = 200 K events/ton - year. me-configuration: Events- E peak = 7.0 GeV, = 8.5 GeV, rate = 675 K events/ton - year pme rate = 540 K events/ton - year. he-configuration: Events- E peak = 12.0 GeV, = 13.5 GeV, rate = 1575 K events/ton - year phe rate = 1210 K events/ton - year. With E-907 at Fermilab to measure particle spectra from the NuMI target, expect to know neutrino flux to ± 5%.

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Jorge G. Morfín - NuFact02 - London, July NuMI Near Hall: Dimensions & Geometry Length: 45m - Height: 9.6m - Width: 9.5m Length Available for New Detector: 26 m Incoming angle: beam: 58 mr

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Jorge G. Morfín - NuFact02 - London, July NuMI Beam Interacts Off-Module-Center Wonderful - inviting - spot for a new detector which could use MINOS near detector as a muon ID/spectrometer!

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Jorge G. Morfín - NuFact02 - London, July Initial Step... MINOS Near Scintillator Strips Planes of C, Fe, Pb

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Jorge G. Morfín - NuFact02 - London, July Detector: Conceptual Design 2m x 2 cm x 2cm scintillator (CH) strips with fiber readout. Fiducial volume: r =.8m L = 1.5: 3 tons of scintillator Downstream half: pure scintillator Upstream half: scintillator plus 2 cm thick planes of C, Fe and W. t 11 planes C = 1.0 ton (+Scintillator) t 3 planes Fe =.95 ton (+MINOS) t 2 planes Pb =.90 ton Readout: combination of VLPC and multi-anode PMT. Use MINOS near detector as muon identifier / spectrometer.

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Jorge G. Morfín - NuFact02 - London, July MINOS Parasitic Running: Event Energy Distribution MINOS oscillation experiment uses mainly le beam with shorter pme and phe runs for control and minimization of systematics. An example of a running cycle would be: t 12 months le beam t 3 months pme beam t 1 month phe beam Assuming 2 such cycles (3 year run) with 2.5x10 20 protons/year: 860 K events/ton. = 10.5 GeV t DIS (W > 2 GeV, Q 2 > 1.0 GeV 2 ) : 0.36 M events / ton. t Quasi elastic: 0.14 M events / ton. t Resonance + “Transition”: 0.36 M events / ton

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Jorge G. Morfín - NuFact02 - London, July MINOS Parasitic Running: x and Q 2 Events / ton

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Jorge G. Morfín - NuFact02 - London, July Prime User: he Event Energy Distribution Run he beam configuration only! = 13.5 GeV For example, 1 year neutrino plus 2 years anti-neutrino would yield: 1.6 M - events/ton 0.9 M - events/ton DIS (W > 2 GeV, Q 2 > 1.0 GeV 2 ): 0.80 M events / ton 0.35 M events / ton t Shadowing region (x < 0.1): 0.3 M events/ton

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Jorge G. Morfín - NuFact02 - London, July he-beam: x and Q 2

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Jorge G. Morfín - NuFact02 - London, July Add a Liquid H 2 /D 2 Target H_2/D_2 Scintillator Strips MINOS Near Additional Tracking Fiducial volume: r = 80 cm. and l = 150 cm. 350 K CC events LH 2 ; 800 K CC events in LD 2 per year he- running. Planes of C, Fe, Pb Additional Tracking

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Jorge G. Morfín - NuFact02 - London, July Detector: Event Rates Event rates (2.5 x protons per year) Parasitic Running Prime User Prime User (3 years) (1 year, he- ) (2 year, he - ) CH2.60 M4.80 M 2.70 M C0.85 M1.60 M 0.90 M Fe0.80 M1.55 M 0.85 M Pb0.75 M1.45 M 0.80 M LH M 0.20 M LD M 0.45 M

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Jorge G. Morfín - NuFact02 - London, July Examples: Expected Statistical Errors-MINOS Parasitic ( running only) Ratio Fe/C: Statistical Errors x B j MINOS 2-cycle %

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Jorge G. Morfín - NuFact02 - London, July Examples: Expected Statistical Errors - he Running Ratios (he, 1 year, DIS): Statistical Errors x B j Fe/ LD 2 Fe/C %9 % High x Bj (he, 1 year, DIS): Statistical Errors x B j CHLH 2 LD % 2 % 1.4 % Taking ratios: beam systematics cancel. Assume relative target systematics are the same as Tevatron Muon Expt. O (1 %).

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Jorge G. Morfín - NuFact02 - London, July Fractional Statistical Errors in Measurements of F i Ratios Assuming he beam 1 year and 2 year One ton fiducial mass of C, Fe and Pb 0.5 ton fiducial mass of D 2

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Jorge G. Morfín - NuFact02 - London, July Six Structure Functions for Maximal Information on PDF’s X = Q 2 = GeV 2 + y 2 F L

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Jorge G. Morfín - NuFact02 - London, July What Can We Learn With All Six Structure Functions? Does s = s and c = c over all x? If so..... Leading order expressions:

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Jorge G. Morfín - NuFact02 - London, July Neutrino Factory: Expected Errors on Measured F’s D 2 Target: r = 50 cm & l = 60 cm. One year exposure. Errors on F 1 better than 10% Assume the Callan-Gross relationship eliminating F 1. Errors now O (1%) or better over most of the x-range.

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Jorge G. Morfín - NuFact02 - London, July Summary Some nuclear effects are predicted to be different for as compared to e/ scattering. Furthermore, Kulagin predicts nuclear effects different for valance as compared to sea quarks. We need to measure these nuclear effects as well as F 2 and xF 3 off different A targets to extract the nuclear parton distribution functions. NuMI Facility excellent for this purpose. The NuMI beam is Intense: t yielding ≈ 860 K events/ton during MINOS run* yielding ≈ 1.6 M events/ton-year in the he_ -mode. NuMI Near Hall: t space for new detector(s) with w(x) ≤ 6 m, h(y) ≤ 4 m,(sum) L ≈ 25 m. NuMI Near Hall Detector studies underway: t “pure scintillator planes” + planes of A: ton fiducial volume - cost O($3M) t liquid H 2 / D 2 (bubble chamber): large target technically feasible - safety requirements..? With these detectors and a 1 year he_ and 2 year he_ exposure, we could measure the ratio (A/ D 2 ) of F 2 for x >.01 to better than 10% and ratio of xF 3 for x >.02 to better than 30% (better than 18 % for x >.02).

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