Studying Nuclear Effects and Structure Functions at the NuMI
Facility Jorge G. Morfn Fermilab NuFact02 London, July 2002 Slide 2
Jorge G. Morfn - NuFact02 - London, July 2002 2 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. Slide 3 Jorge G. Morfn -
NuFact02 - London, July 2002 3 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. Slide 4 Jorge G. Morfn -
NuFact02 - London, July 2002 4 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/9906010 Slide 5 Jorge G. Morfn - NuFact02 - London, July
2002 5 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/0103208 plus a talk at this workshop Neutrinos have the
ability to directly resolve flavor of the nucleons constituents:
interacts with d, s, u, and c while interacts with u, c, d and s. b
hep-ph/9807297 c hep-ph/0103208 Slide 6 Jorge G. Morfn - NuFact02 -
London, July 2002 6 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. Slide 7 Jorge G. Morfn - NuFact02 - London,
July 2002 7 Scattering Nuclear Effects compared to e/ Scattering
hep-ph/9812532 Slide 8 Jorge G. Morfn - NuFact02 - London, July
2002 8 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 PDFs 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. Slide 9 Jorge G. Morfn - NuFact02 - London, July
2002 9 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 Slide 10 Jorge G.
Morfn - NuFact02 - London, July 2002 10 Neutrino Event Energy
Distributions and Statistics Reasonably expect 2.5 x 10 20 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%. Slide 11 Jorge G. Morfn - NuFact02 - London, July 2002 11
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 Slide 12 Jorge G. Morfn - NuFact02 - London,
July 2002 12 NuMI Beam Interacts Off-Module-Center Wonderful -
inviting - spot for a new detector which could use MINOS near
detector as a muon ID/spectrometer! Slide 13 Jorge G. Morfn -
NuFact02 - London, July 2002 13 Initial Step... MINOS Near
Scintillator Strips Planes of C, Fe, Pb Slide 14 Jorge G. Morfn -
NuFact02 - London, July 2002 14 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. Slide 15 Jorge G. Morfn - NuFact02
- London, July 2002 15 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 Slide 16 Jorge G. Morfn - NuFact02
- London, July 2002 16 MINOS Parasitic Running: x and Q 2 Events /
ton Slide 17 Jorge G. Morfn - NuFact02 - London, July 2002 17 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 Slide 18 Jorge G.
Morfn - NuFact02 - London, July 2002 18 he-beam: x and Q 2 Slide 19
Jorge G. Morfn - NuFact02 - London, July 2002 19 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 Slide 20 Jorge G. Morfn - NuFact02
- London, July 2002 20 Detector: Event Rates Event rates (2.5 x 10
20 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 2
0.35 M 0.20 M LD 2 0.80 M 0.45 M Slide 21 Jorge G. Morfn - NuFact02
- London, July 2002 21 Examples: Expected Statistical Errors-MINOS
Parasitic ( running only) Ratio Fe/C: Statistical Errors x B j
MINOS 2-cycle.01 -.02 1.3 %.02 -.03 1.0.03 -.04 0.9.04 -.05 0.8.05
-.06 0.8.06 -.07 0.7 Slide 22 Jorge G. Morfn - NuFact02 - London,
July 2002 22 Examples: Expected Statistical Errors - he Running
Ratios (he, 1 year, DIS): Statistical Errors x B j Fe/ LD 2 Fe/C.01
-.02 11%9 %.02 -.0365.03 -.044 3.04 -.053 2.05 -.062 1.7.06 -.071.7
1.4 High x Bj (he, 1 year, DIS): Statistical Errors x B j CHLH 2 LD
2.60 -.65 0.6 % 2 % 1.4 %.65 -.70 0.7 3 1.7.70 -.75 1.0 4 2.75 -.80
1.3 5 3.80 -.85 2 7 5.85 -.90 3 11 7.90 -.95 5 17 11.95 - 1.0 7 25
16 Taking ratios: beam systematics cancel. Assume relative target
systematics are the same as Tevatron Muon Expt. O (1 %). Slide 23
Jorge G. Morfn - NuFact02 - London, July 2002 23 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 Slide 24 Jorge G. Morfn - NuFact02 - London,
July 2002 24 Six Structure Functions for Maximal Information on
PDFs X = 0.1 - 0.125 Q 2 = 2 - 4 GeV 2 + y 2 F L Slide 25 Jorge G.
Morfn - NuFact02 - London, July 2002 25 What Can We Learn With All
Six Structure Functions? Does s = s and c = c over all x? If
so..... Leading order expressions: Slide 26 Jorge G. Morfn -
NuFact02 - London, July 2002 26 Neutrino Factory: Expected Errors
on Measured Fs 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. Slide 27 Jorge G. Morfn - NuFact02 - London, July
2002 27 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: 3 - 5 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).
