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the following se™tionsD new results in sol—r neutrino —nd in —tmospheri™ neutrino

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P ƒol—r neutrinos

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ele™tron energyD dire™tion —nd the time of the re—™tion —re me—suredF „he o˜t—ined

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„he ux me—surements —re summ—rized in the „—˜le IF ell the exp eriments

showed signi™—ntly lower ux th—n th—t from the ƒƒw predi™tionD while the

dete™tion metho ds —nd the energy thresholds of the me—surement —re dierent

—mong e—™h otherF st is h—rd to expl—in —ll the existing results ™onsistently with

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neutrino is ™onstr—ined ˜y tot—l luminosity of the ƒunF st —g—in m—y suggest strong

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suppression of feEneutrinosF „hose results from the existing exp eriments hints —

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threshold of the existing sol—r neutrino exp erimentsF

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eviden™e of wƒ‡ os™ill—tionF ƒup erEu—miok—nde ™—n provide — huge st—tisti™s for

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form—tion of gerenkov photons on the €w„9s of inner dete™torF „he energy of

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pigure QX „he WS 7 gFvF —llowed region of justEso os™ill—tion ˜y r—t— —nd v—nE

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IQ IR IS

ƒiˆD prejus —nd ƒoud—nEPF „wo w—ter gerenkov exp erimentsD u—miok—nde

—nd swfD h—ve o˜t—ined ™onsistent result whi™h is su˜st—nti—lly sm—ller th—n unityF

„he —nom—ly of "ae r—tio ™—n ˜ e interpreted —s p ossi˜le neutrino os™ill—tionD for

ex—mpleD # 3 # or # 3 # F yn the other h—ndD the result of x ƒiˆ —nd

" e " (

prejus seems to ˜ e ™onsistent with unityD while their st—tisti™s —re not su™ient

for ™on™lusive resultF purthermoreD re™ent d—t— from ƒoud—nEP —gree with the d—t—

from the w—ter gerenkov dete™torsD —lthough the v—lue of unity is still —llowed —t

„—˜le PX ixp eriment—l results on the —tmospheri™ @# G# A r—tioF

" e

ixpF h—t— wg @"aeA a@"aeA

d—t— wg

eElike "Elike eElike "Elike

CHXQS

x ƒiˆ IV QP PHFS QTFV HFWW c

HXPS

prejus US IPS VIFR IQTFP IFHHHFISHFHV

CHXHR

ƒoud—nEP UWFI SRFT HFTUHFIS

HXHT

QPS IVP PSUFQ PTVFH HFSRHFHSHFIP swfEQ@su˜Eqe†A

@A

@multiEqe†A PS RU QHFV RIFP IFRHHFTTHFPI

CHXHT

u—miok—nde@su˜Eqe†A PRV PQR PPUFT QSTFV HFTH HFHS

HXHS

CHXHV

WV IQS TTFS ITPFP HFSU HFHU @multiEqe†A

HXHU

CHXHPW

@A

ƒup erEu—mF@su˜Eqe†A WVQ WHH VIPFP IPIVFQ HFTI HFHRW

HXHPV

CHXHTW

@A

@multiEqe†A PIV IUT IVPFU PPWFH HFTR HFHWU

HXHTP

CHXHSW

@A @A

| PHH | PRRFV HFTU HFHVI @€gA

HXHSR

€relimin—ryF

@A „he dou˜le r—tio is for the ™om˜ined s—mple of pg —nd €g eventsF

P' levelF „hough the theoreti™—l un™ert—inty of —˜solute ux —nd inter—™tion ™ross

se™tions of neutrinos —re l—rgeD they should ™—n™el in the dou˜le r—tioF ren™eD the

sm—ll dou˜le r—tio ™—n ˜ e ™onsidered —s p ossi˜le eviden™e of # 3 # or # 3 #

" e " (

os™ill—tionsF

enother indi™—tion of the os™ill—tion of —tmospheri™ neutrinos is the distortion

of zenith —ngle distri˜ution of neutrino uxF „he ux of —tmospheri™ neutrinos

dep ends on zenith —ngleF „his dep enden™e is ™—used ˜y the dieren™e of ee™tive

thi™kness of —tmosphereF ren™eD the sh—p e of zenith —ngle distri˜ution should ˜ e

symmetri™ for upgoing versus downgoing neutrinosF „ypi™—l iGv for —tmospheri™

I R

neutrinosD for ex—mpleD of I qe† is IH for downgoing —nd IH for upgoingF

„hereforeD p ossi˜le distortion of zenith —ngle distri˜ution is ™le—r eviden™e of neuE

trino os™ill—tionsF ynly the u—miok—nde exp eriment h—s rep orted the zenith —ngle

IP

distri˜utions of neutrino ux for the time ˜ eingF „hey rep orted — p ossi˜le disE

tortion of zenith —ngle distri˜utions in multiEqe† s—mple @i higher th—n roughly

#

P P P

I qe†AD whi™h suggests the neutrino os™ill—tion with
m $ IH e† —nd with

the l—rge mixing —ngle —s shown in pigF VF wu™h more d—t— —re needed to est—˜E

lish the os™ill—tion of —tmospheri™ neutrinosF ƒup erEu—miok—nde ™—n ™olle™t l—rge

st—tisti™s whi™h —re indisp ens—˜le to test the os™ill—tion hypothesis —nd to derive 0 0

)) (a) (b) 2 U

(eV F

2 -0.5 -0.5 m ∆ Kamiokande

log( -1 -1

Kr Kamiokande -1.5 -1.5

-2 B -2

Super- -2.5 -2.5 Kamiokande

-3 -3 Ch I -3.5 -3.5 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1

sin22θ sin22θ

P

P

pigure VX ellowed regions @WH 7 gvA in the @
m Y sin P A sp—™e @—A for # #

" e

os™ill—tion —nd @˜A for # # os™ill—tionF ‚egions with di—gon—l lines show the

" (

IP

—llowed regions o˜t—ined ˜y u—miok—nde F „he sh—ded region in @˜A is the prelimE

in—ry —llowed region ˜y ƒup erEu—miok—ndeF yther lines indi™—te the regions —˜ ove

IT

—nd to their right —re ex™ludedY fD fugey re—™tor exp eriment Y urD ur—snoy—rsk

IU IV

re—™tor exp eriment Y ghD gho oz re—™tor exp eriment YpDprejus fullyE™ont—ined

IR IW

—tmospheri™ neutrinos Y D ™ompil—tion of upw—rd throughEgoing muons d—t— Y

PH

sD swf upw—rd stopping muons F ƒup erEu—miok—nde9s —n—lysis on # # os™ilE

" e

l—tion w—s not re—dyF

the os™ill—tion p—r—meters from dou˜le r—tio —nd zenith —ngle distri˜utionF

‡e h—ve —n—lyzed fullyE™ont—ined @pgA events of RIRFP live d—ys @PSFS ktonE

ye—rsA —nd — p—rti—llyE™ont—ined @€gA events QUHFV live d—ys @PPFV ktonEye—rsAF

sn — pg eventD —ll the ™h—rged p—rti™les —re ™ont—ined in the inner dete™tor —nd

the tot—l energy of the event is fully re™onstru™tedF sn — €g eventD one ™h—rged

p—rti™leD usu—lly "D es™—p es from the inner dete™tor —nd dep osits energy in the

outer dete™torF „o sep—r—te — pg event from — €g eventD we h—ve required tot—l

num˜er of hits in — sp—ti—l ™luster in the outer dete™tor to ˜ e less th—n IHF foth pg

—nd €g events h—ve ˜ een dou˜ly s™—nned ˜y physi™ists to elimin—te ˜—™kground

events due to dete™tor noiseF „hen the vertex p osition of the neutrino inter—™tion

—nd gerenkov rings h—ve ˜ een re™onstru™ted —utom—ti™—lly ˜y — ™omputerF „he

vertex p osition resolution is estim—ted to ˜ e QH ™m for single ring pg eventsF „he

—ngul—r resolution of single ring pgevents is estim—ted to ˜ e Q degreesF pin—llyD

— P m du™i—l ™ut h—s ˜ een —pplied for events in ˜ oth the pg —nd €g s—mplesF

„ot—l visi˜le energy ™utsD i ! QH we† —nd i ! QSH we† h—ve ˜ een —pplied

vis vis

for the pg —nd the €g s—mpleD resp e™tivelyF „he —™™ur—™y of the —˜solute energy

s™—le is estim—ted to ˜ e PFR 7 ˜—sed on sever—l ™—li˜r—tion sour™esX ™osmi™ r—y

throughEgoing muonsD stopping muonsD muonEde™—y ele™tronsD the inv—ri—nt m—ss

H

of % 9s pro du™ed ˜y neutrino inter—™tionsD xiEgf sour™e ™—li˜r—tionD —nd the SEIT

we† vsxegF „he momentum of p—rti™les —re determined from the tot—l num˜er of

photoEele™trons within — UH degrees h—lfE—ngle ™one rel—tive to the tr—™k dire™tionF

p

„he estim—ted momentum resolution for ele™trons —nd muons is PFS7G i CHFS 7

—nd Q 7D resp e™tivelyD where i is the energy of ele™tron in qe† unitF efter those

redu™tionsD the num˜ er of neutrinos is QDRTP for the pg s—mple —nd PHH for the

€g s—mpleF ivents p er d—y is VFR for the pg s—mple —nd HFSR for the €g s—mpleF

sn the pg eventsD single ring events h—ve ˜ een sele™tedF pigure W shows — typi™—l

single ring ’"Elike4 event —nd —n ’eElike4 eventF „here is — dieren™e ˜ etween the

sh—p e of rings in the gureD sin™e — gerenkov ring from ele™trom—gneti™ ™—s™—des

™—use — more diuse photon distri˜ution th—n th—t from muonsF „he p—rti™le

identi™—tion @€shA metho d whi™h uses the distri˜ution of gerenkov photons in

— ring —s well —s the op ening —ngle of the ring —re —pplied to distinguish muons

from ele™tronsF pigure IH shows the result of €sh for single ring pg eventsF „hose

two p e—ks ™orresp onding to " —nd e —re ™le—rly sep—r—ted in these distri˜utionsF

„he pro˜—˜ility of misEidenti™—tion dedu™ed from wonteg—rlo is less th—n HFS7

for the single ring pg s—mpleF „he €g events —re reg—rded —s "Elike eventsD sin™e a)

b)

pigure WX „ypi™—l s—mples of —A I ring eElike event —nd ˜A "Elike event a) 70 b) 120

60 100

50 80 40

60 30

40 20

20 10

0 0 -10 -8 -6 -4 -2 0 2 4 6 8 10 -30 -20 -10 0 10 20 30

PID parameter PID parameter

pigure IHX histri˜ution of the €sh p—r—meter for "Elike events @€sh`HA —nd

for eElikeevents @€shbHA in —A su˜Eqe† s—mple —nd in ˜A multiEqe† s—mpleF

„he ™losed ™ir™les —nd histogr—ms —re for the d—t— —nd for wonte g—rlo eventsD

resp e™tivelyF

WU7 of the €g events —re ™—used ˜y ™h—rged ™urrent # inter—™tionsF

"

„—˜le P shows the n—l results of two dierent energy regionsD n—mely su˜E

qe† —nd multiEqe†D —™™ording to the denition of sele™tion ™riteri— used in

u—miok—ndeF „he su˜Eqe† s—mple is the su˜set of pg events where IA i `

vis

IFQQ qe†D PA € b IHH we†G™ for eElike eventsD —nd QA € b PHH we†G™ for

e "

"Elike eventsF sn su˜Eqe† s—mpleD the num˜ers of single ring eElike —nd "Elike

events —re WVQ —nd WHHD resp e™tivelyD while the exp e™ted num˜ers using rond—9s

ux —re VIPFP —nd IPIVFQ for the single ring eElike —nd "Elike eventsD resp e™tivelyF

„he multiEqe† s—mple is the su˜set of pgevents with i ! IFQQ qe†F „he

vis

num˜er of single ring eElike —nd "Elike events —re PIV —nd IUTD resp e™tivelyD while

the exp e™ted num˜ers —re IVPFU —nd PPWFHF „he num˜er €g events is PHHD while

the exp e™ted num˜er is PRRFVF „hose num˜ ers —re summ—rized in „—˜F PF es

shown —˜ oveD ƒup erEu—miok—nde o˜served sm—ll dou˜le r—tios for ˜ oth the su˜E

CHXHPW

qe† —nd the multiEqe† energy s—mpleF „he dou˜le r—tio —re HFTII HFHRW

HXHPV

CHXHSW

—nd HFTTS HFHVI for the su˜Eqe† pg s—mple —nd ™om˜ined s—mple of multiE

HXHSR

qe† pg —nd €gD resp e™tivelyF y˜t—ined dou˜le r—tios in ƒup erEu—miok—nde —re

therefore in™onsistent with unityD —nd ™onsistent with the previous results of w—E

ter gerenkov exp erimentsF „husD the —tmospheri™ neutrino —nom—ly h—s ˜ een

est—˜lishedF

pigF II shows the momentum distri˜ution for the pg eventsF yne ™—n see th—t

the sh—p e of the distri˜utions for the eElike —nd "Elike events —re repro du™ed well

˜y the wonte g—rloF ‡e ™—n not determine whether # de™it or # ex™ess t—kes

" e

pl—™e due to PS 7 un™ert—inty in —˜solute norm—liz—tion ™oming from un™ert—inty

of neutrino ux —nd of neutrino inter—™tion ™ross se™tionsF „he de™it@ex™essA of

events in the muons @ele™tronsA of the d—t—D howeverD ™—n not ˜ e expl—ined within —

S 7 un™ert—inty of exp e™ted "ae r—tioF pigure IP shows the dou˜le r—tio vs lepton

momentum in ˜ oth of the s—mplesF st —pp e—rs th—t the sm—ll dou˜le r—tio do es not

dep end strongly on the momentumF pigure IQ shows the dou˜le r—tio vs h D

w —ll

dist—n™e from the inner w—llF i—™h ˜in of h is ™hosen to give the s—me du™i—l

w —ll

m—ssF st is ™le—r th—t the dou˜le r—tio is not dep endent on the vertex p ositionF

„his proves the o˜t—ined sm—ll dou˜le r—tios —re not due to ™ont—min—tion from

—ny kind of in™oming p—rti™les like ™osmi™ r—y muons or neutrons from ro ™kF

„he higher energy neutrinos h—ve the ˜ etter —ngul—r ™orrel—tion to the lepton

pro du™ed vi— gg inter—™tionF por ex—mpleD the —ngle ˜ etween the neutrino —nd

the lepton is roughly PH degrees in multiEqe† s—mpleF „he dire™tion of neutrinos

™—n ˜ e me—sured ˜y using the dire™tion of — single ringF pigF IR shows the zenith

—ngle distri˜ution of "Elike events —nd eElike events in su˜Eqe† —nd multiEqe† C

€g s—mples together with wonte g—rlo exp e™t—tionsF e l—rge de™it of upw—rd

going neutrinos —re signi™—ntly o˜served in the multiEqe† "Elike s—mpleF xote

th—t —ny system—ti™ ee™ts due to the ™ross se™tion —nd neutrino ux ™—l™ul—tion

—re ™—n™eled in the symmetry of the zenith —ngle distri˜utionD —nd ™—nnot expl—in

the presented l—rge distortionF „he hypothesis of neutrino os™ill—tions ™—n n—tuE

r—lly expl—in this —symmetryF €relimin—ry os™ill—tion —n—lysis —ssuming # 3 #

" (

os™ill—tion h—s ˜ een m—deF „he WH 7 gFvF —llowed region is shown in pig VF elE

P

though the suggested region is slightly lower in
m th—n th—t of u—miok—ndeD

Q P

the overl—p region with the u—miok—nde result —pp e—rs —t —round SIH e† F

R ‚esults in upw—rdEgoing muons

enother indi™—tion of neutrino os™ill—tions ™—n ˜ e derived from upw—rdEgoing

muon d—t—F „he upw—rdEgoing muons —re pro du™ed ˜y ™h—rged ™urrent # interE

"

—™tions in the ro ™k ne—r the dete™torF sf the energy of muons is l—rger th—n sever—l 200 a) 300 b)

175 250

150 200 125

100 150

75 100

50 50 25

0 0 0 200 400 600 800 1000 1200 1400 0 200 400 600 800 1000 1200 1400 MeV/c MeV/c

80 120 c) d) 70 100 60

80 50

40 60

30 40 20

20 10

0 0 100 1 10 100 110

GeV GeV

pigure IIX womentum distri˜ution for @—AeElike —nd @˜A"Elike events in the su˜E

qe† s—mple —nd ™A eElike —nd dA "Elike events in the wultiEqe† s—mple from

ƒup erEu—miok—ndeF „he histogr—ms show the wg predi™tionF 4 R 1.4 (a) (b) 3.5 1.2 3 1 2.5 0.8 2

0.6 1.5

0.4 1

0.2 0.5

0 0 0 500 1000 1500 1 10 100

momentum (MeV/c) momentum (GeV/c)

pigure IPX „he momentum dep enden™e of the dou˜le r—tio ‚ for —A su˜Eqe† —nd

˜A multiEqe†F „he ™losed ™ir™les show the d—t—F „he histogr—ms with dotted line

P

P

show the exp e™ted one with # 3 # os™ill—tion in the ™—se of @
m Dsin P Aa

" (

Q

@S  IH DIFAF

2.5 2.5

2.25 a) 2.25 b)

2 2

1.75 1.75

1.5 1.5 R R 1.25 1.25

1 1

0.75 0.75

0.5 0.5

0.25 0.25

0 0 0 200 400 600 800 1000 1200 1400 1600 0 200 400 600 800 1000 1200 1400 1600 (cm) (cm)

Dwall Dwall

pigure IQX „he dou˜le r—tio ‚ in e—™h h ˜in for —A the su˜Eqe† —nd ˜A the

w —ll

multiEqe† s—mpleF „he Pm du™i—l volume ™uts —re —lso shownF 300 300 (a) (b)

200 200 Number of Events Number of Events

100 100

0 0 -1 -0.5 0 0.5 1 -1 -0.5 0 0.5 1

COS Θ COS Θ 200 200 (c) (d)

150 150

100 100 Number of Events Number of Events

50 50

0 0 -1 -0.5 0 0.5 1 -1 -0.5 0 0.5 1

COS Θ COS Θ

pigure IRX „he dou˜le r—tio ‚ —s — fun™tion of zenith —ngle for @—Asu˜Eqe† eElikeD

@˜A su˜Eqe† "ElikeD @™A multiEqe† eElikeD @dA multiEqe† "Elike eventsF ristogr—ms

with solid line show the exp e™t—tion from wonte g—rlo without os™ill—tionsF „he

h—t™hed ˜ oxes show the errors due to wonte g—rlo st—tisti™sF ristogr—m with

P

P

d—shed line show the exp e™t—tion with # 3 # os™ill—tion with @
m Dsin P Aa

" e

Q

@S  IH DIFAF gos aI ™orresp onds to down going p—rti™lesF

qe†D they p—ss through the dete™torF „hese —re ™—lled upw—rdEgoingEthrough

muonsF „he typi™—l neutrino energy is the order of IHH qe† for upw—rdEgoingE

through muonsF

pw—rdEgoing through muons h—ve ˜ een sele™ted in QTP live d—ys d—t— s—mE

pleF ell the dire™tion —nd entering p osition of muons h—ve ˜ een re™onstru™ted

—utom—ti™—lly ˜y — progr—mD then l—ter ˜y m—nu—l tting to me—sure them more

pre™iselyF gosmi™ r—y muonsD whi™h —re the m—in ˜—™kground eventsD h—ve ˜ een

e—sily reje™ted ˜y —pplying the zenith —ngle ™ut @ ™os  H AF „he p—th length

z

of the muon tr—™k in the inner dete™tor h—s ˜ een required to ˜ e more th—n U mF

„his ™orresp onds to — IFU qe† ™utF „he tot—l o˜served num˜er of upw—rdEgoingE

through muons is RHW in QTP live d—ysF „he exp e™ted num˜er of upw—rdEgoing

through muons from — ™—l™ul—tion is RRS  VWF st is h—rd to ™omp—re the o˜t—ined

num˜er of upgoing muons to the exp e™ted one sin™e —˜solute num˜er h—s —˜ out

PH 7 un™ert—inty due to the ux of —tmospheri™ neutrinos —nd the ™ross se™tionF

roweverD p ossi˜le distortion of zenith —ngle distri˜ution is free from su™h systemE

—ti™sD —nd ™ould ˜ e eviden™e of neutrino os™ill—tions just —s in the vertexE™ont—ined

event d—t—F

pigure IS shows the zenith —ngle distri˜ution o˜t—ined from u—miok—nde —nd

from ƒup erEu—miok—nde together with the exp e™t—tionF „he ™losed ™ir™les —nd

op en ™ir™les show the d—t— of u—miok—nde —nd of ƒup erEu—miok—ndeD resp e™E

tivelyF „hose d—t— of two exp eriments —gree wellF „he exp e™ted distri˜utions in

P

P Q

the ™—se of no os™ill—tion —nd the os™ill—tion with @
m Dsin P Aa@S IH DIFAF

for ˜ oth exp eriments —re —lso shown with thin solid lines —nd with thin d—shed

linesD resp e™tivelyF „hose plotted histogr—ms —re ˜ estEtted ones within PH 7 unE

™ert—inty in —˜solute norm—liz—tionF „he d—t— of two exp eriments —re ™onsistent

with e—™h exp e™t—tion with no os™ill—tion with in errorsD though the st—tisti™s is

not enough so f—rF roweverD it is interesting th—t the hypothesis of # 3 # osE

" x

P

™ill—tion with the p—r—meter suggested ˜y the ™ont—ined d—t—D for ex—mple @
m D

P

Q P

sin P Aa@S  IH e† DIFAD —grees well with the d—t—D orD even ts ˜ etterF epE

p—rently mu™h more st—tisti™s —nd further study of system—ti™ error —re needed to

give — de™isive —nswer for neutrino os™ill—tionsF

pigure ISX „he zenith —ngle distri˜ution of upw—rd going through muons from

u—miok—nde @full ™ir™leA —nd ƒup erEu—miok—nde @op en ™ir™leAF ristogr—ms show

the exp e™ted distri˜utions from no os™ill—tion @thi™k solid —nd d—shed lines for

ƒup erEu—miok—nde —nd u—miok—ndeD resp e™tivelyA —nd from # # os™ill—tion

" (

P

P Q P

with
m aS IH e† —nd sin P a I @thin solid —nd d—shed lines for ƒup erE

u—miok—nde —nd u—miok—ndeD resp e™tivelyAF „he results —nd exp e™ted lines for

u—miok—nde were multiplied ˜y — f—™tor HFVIW to s™—le its geometri™—l ee™t to

ƒup erEu—miok—ndeF „he exp e™ted lines —re the ˜ est tted ones o˜t—ined within

the —˜solute s™—le un™ert—inty of PH7F

RFI puture longE˜—seline exp eriment —t uiu

„he ee™t of neutrino os™ill—tion suggested ˜y the —tmospheri™ neutrino d—t— ™—n

˜ e studied ˜y longE˜—seline neutrino os™ill—tion exp eriments using high intensity

# ˜ e—mF yne of the p ossi˜le exp eriment is the one ˜ etween uiuE€ƒ —nd ƒup erE

"

PI

u—miok—nde @™—lled uPuAF st h—s the ˜—seline length of PSH km —nd the —ver—ge

P P

energy of # ˜ e—m is roughly IFS qe† so th—t it is just sensitive to the
m $ IH

"

P

e† region suggested ˜y the ƒup erEu—miok—nde d—t—F

„he IP qe† proton ˜ e—m is extr—™ted from uiuE€ƒ within I "se™ ˜y every

C

P se™ondsF % 9s pro du™ed ˜y IP qe† protons —re fo ™used ˜y horn m—gnets —nd

C

de™—y into " # in the PHH m long de™—y tunnelF „he fr—™tion of # in the ˜ e—m

" e

is less th—n I 7F „here —re two kind of ˜ e—m monitorsD the % monitor —nd the

" monitorD in the de™—y tunnelF „he % monitor downstre—m the horn m—gnets is

— g—s gerenkov dete™tor whi™h me—sures the emission —ngle of gerenkov photons

pro du™ed ˜y the % ˜ e—m with v—rious g—s pressureF „his monitor provides the

inform—tion —˜ out distri˜ution of momentum —nd divergen™e of % ˜ e—mF „he

" monitor downstre—m the ˜ e—m dump me—sures the prole of "9s from the %

de™—ysF „hose two monitors —re useful to underst—nd pro du™tion of # ˜ e—mF

"

„here is — front dete™tor QHH m —p—rt from the t—rget to me—sure initi—l ux of

# ˜ e—mF „he front dete™tor ™onsists of the pine qr—in hete™tor —nd IHHH ton w—E

"

ter gerenkov dete™torF „he pine qr—in hete™tor is — tr—™kingEtype dete™tor whi™h

™onsists of — ’s—ndwi™h4 of s™intill—ting ˜ er tr—™ker —nd w—ter l—yer —s — t—rgetF

„he —im of the dete™tor is to me—sure the —˜solute # ux with S 7 —™™ur—™y ˜y

"

™hoosing qu—siEel—sti™ gg inter—™tionF „he IHHH ton w—ter gerenkov dete™tor h—s

the s—me ™ongur—tion —s ƒup erEu—miok—ndeF „he —im of the dete™tor is to study

the dete™tor resp onse whi™h is ™h—r—™teristi™ for w—ter gerenkov te™hnique with

neutrino ˜ e—m wellEme—sured ˜y the pine qr—in hete™torF

„he num˜er of ™h—rged ™urrent inter—™tions —t ƒup erEu—miok—nde is —˜ out

PH

QSH for IH protons on t—rget @€y„A in twoye—rs of runningF „his exp eriment

™—n se—r™h for # 3 # —nd # 3 # indep endentlyF # 3 # os™ill—tion ™—n

" e " ( " e

˜ e o˜served —s —n —pp e—r—n™e of eElike events —t ƒup erEu—miok—ndeF # 3 #

" (

os™ill—tion ™—n ˜ e o˜served —s p ossi˜le distortion of # energy sp e™trum whi™h

"

™—n ˜ e re™onstru™ted from single ring "Elikeevents —t ƒup erEu—miok—ndeF pigE

ure IT shows re™onstru™ted energy sp e™trum of # 9s with noEos™ill—tion —nd with

" os™ill—tionF yne ™—n see the signi™—nt distortion in the sp e™trum in the ™—se of a) b)

c) d)

pigure ITX „he exp e™ted energy distri˜ution of # —t ƒup erEu—miok—nde re™onE

"

stru™ted from single ring "Elike eventsF „he histogr—ms show the d—t— without

os™ill—tionF „he ™rosses shows the d—t— in the ™—se of # # os™ill—tion with

" (

P

P P P P Q P

sin P a I —nd —A with
m aIH e† D ˜A with
m aS IH e† D ™A with

P Q P P Q P

m aQ IH e† D dA with
m aP IH e† F 0

)) 10 2 (eV 2 m

∆ -1 99% C.L.

10 90% C.L. log( σ 3

-2 10

-3 10

-4 10 0 0.2 0.4 0.6 0.8 1 2

sin 2θ

P

P

pigure IUX „he sensitivity plot in @
m Dsin P A sp—™e for # dis—pp e—r—n™e se—r™h

"

PH

with IH €y„ ˜y using the neutrino energy sp e™trum —n—lysisF i—™h ™ontour —t

WH 7 gFvFDWW 7 gFvF —nd Q ' level is shownF elso shown —re the —llowed region

from u—miok—nde —nd ƒup erEu—miok—nde resultsF

P

os™ill—tion with
m suggested ˜y —tmospheri™ neutrino d—t—F „he sensitivity for

P

the # dis—pp e—r—n™e me—surement is plotted in pigure IUF „he region where
m

"

P

Q P

is gre—ter th—n Q  IH e† —nd sin P is gre—ter th—n HFT ™—n ˜ e explored ˜y

this exp erimentF

„he ™onstru™tion of the new neutrino ˜ e—mline h—s ˜ een st—rted in IWWTF „he

inst—ll—tion of the front dete™tor will ˜ e st—rted from yg„D IWWVF „he rst neuE

trino ˜ e—m will ˜ e extr—™ted from t—nDIWWWF „he physi™s run will ˜ e st—rted eprD

IWWW —nd ™ontinues for P$Q ye—rsF st will give — ™on™lusive result for the os™ill—tion

p—r—meter —nd mo desF

S gon™lusion

ƒup erEu—miok—nde is the l—rgest underground w—ter gerenkov dete™tor dedi™—ted

to the dete™tion of neutrinos —nd proton de™—ysF ƒup erEu—miok—nde h—s ˜ een

™ontinuously running from epril ID IWWT —nd ™olle™ts mu™h gre—ter st—tisti™s of

neutrino d—t— th—n h—s ˜ een —™hieved so f—r ˜y —ny underground neutrino exp erE

imentF

„he prelimin—ry results in sol—r neutrino —re rep orted ˜—sed on QUR liveEd—ys

d—t—F „he o˜served ux of sol—r neutrinos is —pp—rently sm—ller th—n the exp e™t—E

tion of ƒƒwD —nd ™onsistent to the previous result of u—miok—ndeF „he h—yGxight

dieren™e is ™onsistent to zero within errorF „his result p—rti—lly ex™ludes the lower

P

m region in the l—rgeE—ngle solution of wƒ‡F „he o˜served energy sp e™trum

of d—t—Gƒƒw is not signi™—ntly distorted with ™urrent errors though — t with —

P

distorted sp e™trum gives ˜ etter 1 th—n ™omp—rison to the undistorted sh—p eF

„he prelimin—ry results in —tmospheri™ neutrinos —re presented ˜—sed on RIR

liveEd—ys d—t—F „he dou˜le r—tios —re me—sured ˜ oth in the su˜Eqe† s—mple —nd

the multiEqe† s—mpleF foth —re —pp—rently sm—ller th—n unity —nd ™onsistent

with the previous u—miok—nde resultF woreoverD — l—rge de™it of upgoing # is

"

o˜served in multiEqe† s—mpleF „hose —nom—lies —re h—rd to expl—in ˜y st—nd—rd

physi™s —nd ™ould ˜ e eviden™e of neutrino os™ill—tionsF „he prelimin—ry results

in upw—rdEgoingEthrough muons ˜—sed on QTP d—ys d—t— —re —lso rep ortedF „he

o˜served zenith —ngle distri˜ution is still ™onsistent with the exp e™t—tion within

errorsF roweverD it is —lso ™onsistent with # 3 # os™ill—tion with the p—r—meters

" x

suggested ˜y the —tmospheri™ resultF wu™h more st—tisti™s —re needed to give— de™isive —nswer for neutrino os™ill—tionsF

„he p—r—meter region suggested ˜y —tmospheri™ neutrino result will ˜ e exE

plored ˜y the long ˜—seline exp eriment using — high intensity # ˜ e—m from uiuE

"

€ƒ st—rting in IWWWF ‡e m—y ™onrm # 3 # os™ill—tions ˜y dete™ting — p ossi˜le

" x

distortion of the # energy sp e™trum —t ƒup erEu—miok—ndeF st is ex™iting th—t osE

"

P

P Q

™ill—tions with the p—r—meters @
m Dsin P A$ @S  IH DIAD whi™h —re —llowed ˜y

˜ oth the u—miok—nde —nd the ƒup erEu—miok—nde —tmospheri™ neutrino resultsD

™—use l—rge distortion of the # energy sp e™trumF rop efullyDwem—y determine

"

the mo de —nd p—r—meter of neutrino os™ill—tions —nd op en — new eld of neutrino

physi™sF

‚eferen™es

‘I“ „he ƒup erEu—miok—nde ™oll—˜ or—tionD snstitute for gosmi™ ‚—y ‚ese—r™h

@sg‚‚AD niversityof„okyoD qifu niversityD x—tion—l v—˜ or—tory for righ

inergy €hysi™s @uiuAD uo˜ e niversityD wiy—gi niversity of idu™—tionD xiE

ig—t— niversityD ys—k— niversityD„ok—i niversityD„okyo snstitute of „e™hE

nologyD„ohoku niversityD foston niversityD fro okh—ven x—tion—l v—˜ or—E

toryD niversity of g—liforni—D srvineD g—liforni— ƒt—te niversityD hominguez

rillsD qeorge w—son niversityD niversityofr—w—iiD vos el—mos x—tion—l

v—˜ or—toryD vouisi—n— ƒt—te niversityD niversity of w—ryl—ndD ƒt—te niE

versity of xew ‰ork —t ƒtony fro okD niversityof‡—rs—wD niversityof

‡—shingtonF

‘P“ ƒeeD for ex—mpleD tFxFf—h™—ll —nd wFrF€insonne—ultD ‚evF wo dF €hysF TU

@IWWSA UVIF

‘Q“ uFv—ndeD to ˜ e pu˜lished in x eutr ino WTD €ro ™eedings of the IUth sntern—E

tion—l gonferen™e on xeutrino €hysi™s —nd estrophysi™sD relsinkiD pinl—ndD

tune IWWTF ƒee —lso fF„Fglevel—nd et —lFD xu™lF €hysF f @€ro ™F ƒupplFA QV

@IWWSA RUF

‘R“ ‰Fpukud— et —lFD €hysF ‚evF vettF UU @IWWTA ITVQF

‘S“ tFxFe˜ dur—shitov et —lFD €hysF ‚evF vettF UU @IWWTA RUHVF

‘T“ ‡Fr—mp el et —lFD €hysF vettF f QVV @IWWTA QVRF

‘U“ „he ƒup erEu—miok—nde ™oll—˜ or—tionD dr—ft in prep—r—tionF

‘V“ ƒeeD for ex—mpleD xFr—t— —nd €Fv—ng—™kerD €reprint veƒƒxƒEeƒ„ WUGPW

@w—yIWWUAD —nd referen™es thereinF

‘W“ ƒF€Fwikheyev —nd eF‰uFƒmirnovD ƒovF tF xu™lF €hysF RP @IWVSA WIQY

vF‡olfensteinD €hysF ‚evF h IU @IWUVA PQTWY i˜idF PH @IWUWA PTQRF

‘IH“ fe™kerEƒzendy et —lFD €hysF ‚evF h RT @IWWPA QUPHF

‘II“ ‚Fgl—rk et —lFD to ˜ e pu˜lished in €hys ‚evF vettF ‚Fgl—rkD priv—te ™ommuE

ni™—tion for the @"aeA a@"aeA v—lueF

d—t— wg

‘IP“ ‰Fpukud— et —lFD €hysF vettF f QQS @IWWRA PQUF

‘IQ“ wFegliett— et —lFD iurophysF vettF VD @IWVWA TIIF

‘IR“ uFh—um et —lFD F €hysF g TT @IWWSA RIUF

‘IS“ ‡F‡FwFellison et —lFD €hysF vettF f QWI @IWWUA RWIF wFgFqo o dm—nnD for

the ƒoud—nEP ™oll—˜ or—tionD t—lk presented —t ƒixth gonferen™e on the snterE

se™tions of €—rti™le —nd xu™le—r €hysi™sD wont—n—D ƒeD w—yEtuneD IWWUF

‘IT“ fF e™hk—r et—lFD xu™lF €hysF f RQR @IWWSASHQF

‘IU“ qF ƒF †idy—kin et—lFD ƒovF €hysF ti„€ UID RPR @IWWHAY ti„€ vettF SWD QWH

@IWWRAF

‘IV“ gho oz ™oll—˜ or—tionD preprint hepEexGWUIIHHHP @S xov IWWUA

‘IW“ ‡F pr—ti et—lFD €hysF ‚evF h RV @IWWQA IIRHF

‘PH“ ‚F fe™kerEƒzendy et—lFD €hysF ‚evF vettF TW @IWWPA IHIHF

‘PI“ uFxishik—w— sxƒE‚epFEWPRD @IWWPAF