E/L decays to K&r in j7p annihilation at rest

12 Pages·2003·1.12 MB·English

2 rebmevoN 1995
PHYSICS LETTERS B
REINESLE scisyhP sretteL B 361(1995) 187-198
syaced ot r&K ni noitalihinna ta tser
E/L j7p
XILEBO noitaroballoC
.A ,anitreB M. ,aihcsurB .B ,aadereC S. De ,aortsaC .A ,aitterreF D. ,aillaG .B ,”ebbocaiG
U. inocraM ,a M. iloP ,*pa M. ,aininicciP N. ,airaseC-inirpmeS .R ihgipS ,a S. ihcceV ,a
.A ,ainazzeV F. ,aittogiV M. ,aalliV .A elatiV ,a .A iloccoZ ,a M. ,binidarroC .A ,balleznoD
.E idoL inizziR b, .L illerutneV b, .A inoneZ ‘, .C olaciC d, .A ,diaL .A inosaM d, .L Musad,
G. Puddu d, S. icreS d, P.P. ,dvokinmeT G. iasU d, V.G. ,eveelbA O.Yu. vosineD ,e
,e
.M.A yksnevtsedhzoR M.G. ,evokinhzopaS .I.V ,ekayterT P. ,fittonaiG .C ,fodlarauG
.A oranaL ,f V. inirehcuL ,f F. uitihciN ,l,f .C ucsarteP ,**f .A ,’v’acsoR .C ,snoivaC
U. idlatsaG g, G. ,anoraM M. odnaroM ,h G. iloicsidneB ,i V. inippiliF ,i .A ,’anatnoF
P. angatnoM ,i .A idnotoR ,i .A ,’oniaS P. inivlaS ,i F. ,jartselaB .E ,jattoB .T ,jinasserB
M.P. Bussa j, .L ,jossuB D. Calvjo, P. ,jollereC S. ,latsoC .A ,jolleicileF .L ,jorerreF
.A ,jippiliF .R ’iningafraG J, .A ,jossarG .A aroiggaM ,j S. ,jollecraM N. ,2,jiarhkafriM
D. ,jireiznaP D. ,janeraP .E ,jottessoR F. ,jollesoT G. ,jisoZ M. ,kollengA F. izzaI ,k
.B ,kitteniM G. ,tiluaP S. ,eorasseT .L ”itnaS
a
Dipartimento di Fisica, Universita di Bologna and INFN, Sezione di Bologna, Bologna, Italy
h Dipartimento di Chimica e Fisica per i Materiali, Universitd di Brescia and INFN, Sezione di Torino, Torino. Italy
c Dipartimento di Chimica e Fisica per i Materiali, Universitd di Brescia and INFN, Sezione di Pavia, Pavia, Italy
d Dipartimenfo di Scienze Fisiche, Universita di Cagliari and INFN, Sezione di Cagliari, Cagliari, Italy
e Joint Institute for Nuclear Research, Dubna, Russia
f Laboratori Nazionali di Frascati dell’INFN, Frascati, Italy
g Laboratori Nazionali di Legnaro dell’INFN, Legnaro, Italy
h Dipartimento di Fisica, Universitd di Padova and INFN, Sezione di Padova, Padova, Italy
i
Dipartimento di Fisica Nucleare e Teorica, Universitd di Pavia, and INFN Sezione di Pavia. Pavia, Italy
j Dipartimento di .acisiF Universild di Torino and INFN, Sezione di Torino, Torino, Italy
k Politecnico di Torino and INFN, Sezione di Torino, Torino, Italy
e Istituto di Fisica, Universita di Trieste and INFN, Sezione di Trieste, Trieste, Italy
m Istituto di Fisica. Universita di Udine and INFN? Sezione di Trieste, Trieste, Italy
devieceR 1 rebmetpeS 1995
:rotidE .L tenatnoM
tcartsbA
ehT stluser fo eht sisylana of 3940 (KKsr)wr stneve morf a elpmas of 18 snoillim p?~ snoitalihinna ni the diuqil
negordyh target of the XILEBO retemortceps at RAEL (CERN) are .detneserp ehT ecneserp of two ralacsoduesp states at
,2c/VeG200.0f614.1 htiw htdiw ,2c/VeG400.0f050.0 tadna 1.46f0.01 ,2c/VeG htiw htdiw ,2c/VeG510.0f501.0 si
reiveslE ecneicS .V.B
IDSS 0370-2693(95)01136-6
188 OBELIX Collaboration/ Physics Letters B 361 (199.5) 187-198
.dehsilbatse ehT rethgil mass ecnanoser syaced ylniam ot ylbissop htiw lanif etats snoitcaretni and a small noitubirtnoc
Ki?n,
gnimoc morf .rm ehT rehgih mass O-+ ,etats hcihw is nees rof eht tsrif emit ni pp noitalihinna at ,tser syaced ylno ot
.?J*K Masses, widths and yaced sedom are ni tnemeerga htiw the sisylana of J/g evitaidar yaced demrofrep yb eht Mark
III .noitaroballoC morF eht tif eht ytirap-G was denimreted ot eb +l. ehT tnanimod ydob-eerht yaced edom fo eht rethgil
ralacsoduesp is devresbo rof eht tsrif emit ni this .tnemerusaem
A gnikirts noitatcepxe fo Quantum -manyDomorhC sensus that eht dnuorg etats llabeulg seil dnuora 1.5
its )DCQ( , eht n&ebA-non dleif yroeht fo gnorts -ni ,2clVeG htiw an ytniatrecnu fo a wef 0.1 .2c/VeG
,noitcaret is eht ecnetsixe fo wen dnik fo ,snosem edam gnomA eht gq-non ,setadidnac eht esac fo eht
E/L
yb ecnelav ,snoulg eht sllabeulg gg( ro ,)ggg ro yb nosem ,seipucco ,yldetbuodnu a laiceps .elor ehT
E-
serutximda fo quarks, antiquarks and snoulg nosem was derevocsid ni 1963 ni snoitalihinna at
(qqg), fip
dellac .sdirbyh rehtonA elpmaxe fo 4q-non snosem era tser [ 51, ni eht )r?jK( yaced ,edom at a mass fo 1.425
krauqitlum states, 2clVeG and htiw ytirap-nips roF ylraen 30
qqqq. Jpc O-+.
An latnemirepxe noitamrifnoc fo eht ecnetsixe fo sraey lareves stnemirepxe dekool at eht 1.4 2c/VeG
eseht states dluow eb an tnatropmi tset fo eht yroeht mass noiger ni a yteirav fo tnereffid :snoitcaer morf
and dluow evig latnemadnuf noitamrofni no eht -eb at tser and ni thgilf ot r ro larehpirep decudni
pp K
ruoivah fo QCD ni eht tnemenifnoc .noiger ;snoitcaer morf and lartnec noitcudorp ot yy
pp rp
ehT hcraes rof qq-non snosem has deedni -per snoisilloc ni -efe ;noitalihinna morf evitaidar -ed
J/(/I
detneser eht main noitavitom fo thgil nosem -ceps yac ot cinordah .yaced A gnilzzup oiranecs denrut
J/$
ypocsort revo eht last .sraey ehT ytluciffid fo this ,tuo ni hcihw deraeppa that eht quantum srebmun as-
hcraes is yltsom eud ot eht ytixelpmoc fo eht nordah detaicos htiw eht states devresbo ni eht mass murtceps
,murtceps erehw states ,palrevo ni eht emas mass ro l++) ] erew tnereffid rof tnereffid -orp
q4 [ ~(0~~) E(
,noiger htiw eht laidar .snoitaticxe ,revoeroM ynam noitcud ,smsinahcem and eht erew ton ,euqinu
Jpc
nosem stenon ypucco a ralimis mass .noiger ,suhT neve nihtiw eht emas epyt fo .noitcaer sihT del ot an
assigning states ot stenon nac eb a detacilpmoc task, esnetni ,etabed llits ton ,dedulcnoc nwonk as eht
“E/L
and woh ot ezingocer a nosem as ro 4q-non is a no eht erem ecnetsixe fo eht wen states and
qQ puzzle”,
cisab .melborp ,ylsuoivbO an assignment fo quantum no eht ytilibissop that eno ro erom fo meht thgim eb
srebmun hcihw era ton dewolla ot a etats ,-+O( a qq-non ,nosem ekil a ,llabeulg a ,dirbyh ro a -itlum
qq
).cte dluow tneserper eht tseb erutangis rof an citoxe krauq etats [ .131-6
.etats erutaN is erom detacilpmoc and up ot won on ehT XIRETSA noitaroballoC at RAEL devresbo
citoxe etadidnac syalpsid ylsuougibmanu neddibrof [ 141, ni noitalihinna at tser ni suoesag -rat
pp
quantum .srebmun ,teg a erutcurts at 1.413 2clVeG ni eht lennahc
etipseD all this, eht tenon erutcurts is eht tseb loot A O-+ assignment was ,decuded
K*K&,T~T~T~.
ew possess rof gnizingocer 4q-non ,snosem rehtegot hguohtla a ytirap-nips sisylana dluoc ton eb demrofrep
htiw an noitacidni fo eht masses, hcihw era ton nwonk eud ot eht detimil statistics.
a ,iroirp tub nac eb dnuof morf sehcaorppa hcus as weN thgil no eht elzzup was dehs yb a laitrap evaw
deripsni-DCQ laitnetop .sledom gnomA ,eseht eht sisylana fo eht E/L noiger demrofrep yb eht Mark
ledom tliub yb yerfdoG and rugsI [ 1 ] is netfo desu ni III noitaroballoC no eht KRr lanif etats morf J/ti
redro ot tset rehtehw a wen derevocsid ecnanoser seod evitaidar yaced [ 151. morF a data elpmas fo ylhguor
ro seod ton gnoleb ot eno fo eht .stenon seidutS 700 stneve morf 6 snoillim detcelloc data, Mark III
qq
fo ecittal QCD [ 14-2 raeppa ot eb gnimoc ot a -noc deterpretni eht E/L signal as eud ot eht ecneserp fo
eerht gnippalrevo secnanoser ,nees rof eht tsrif ,emit
all at a :emit
*
Dipartimento di Energetica, Universid di Firenze. )i )0241(~ htiw Jpc = O-+ and yaced aiv
’
Department of High Energy Physics, Institute of Atomic r7)089(aa
Ph* yOsinc sl,e aBveu chofa raebsts,e nRceo mfarnoima. Sahid Beheshty University, Dept. of )ii (]r )0941 htiw Jpc = O-+ and yaced aiv K*i?
Physics, 19834 Tehran, Iran.
OBELIXC ollaboration/PhysicsL ettersB 361 (1995) 187-198 189
)iii if ( )0241 htiw cpJ = l++ and yaced aiv K*E. noak and eerht snoip ot eb .dezingocer Channels
oslA eht DM2 noitaroballoC dnuof eerht serutcurts ekil and
r+r-rTT+rr-nd’ (n = 0,l) K*K$r%&
ni eht lennahc J/$ + yKl?r [ 161, revewoh yeht (n = 0,l) erew detcejer yb lacitamenik tif and did
erew ton dnuof ot eb ,tnetsisnoc as raf as yaced sedom ton etubirtnoc ot eht aK missing mass .noiger A tuc
era ,denrecnoc htiw esoht fo Mark .III no -TTmfTTr7 tnairavni mass was osla ,deilppa ni redro
,yltneceR a erutcurts ni eht L/E ,noiger gniyduts eht ot tcejer eht )1 .slennahc llA
K*errn$ (n >
syaced ot ,TIV]~ was devresbo ni noitalihinna at eseht stuc derutaef a hgih )%09>( and htooms -iffe
pp
tser ni diuqil negordyh yb eht latsyrC lerraB -oballoC ycneic rof eht detceles lennahc and dewolla ot niatbo
noitar [ 171. a tnetsisnoc dnuorgkcab .noitcuder
nI this repap ew troper eht tsrif noitavresbo fo owt ehT derauqs missing mass fo eht
K*~-~T+T- se-
sralacsoduesp ni eht ,noiger nees ni -alihinna detcel stneve is dettolp ni .giF la. A raelc aK sig-
E/L pp
noit at ,tser ni eht lennahc A spin- nal is ;tneserp eht dehctah aera shows eht stneve -es
K* @tiss~Fmf~TT-.
ytirap sisylana was ,demrofrep gnidrocca ot hcihw eht detcel yb lacitamenik tif htiw .L.C > %09 rof eht
rethgil ecnanoser has a tnanimod ydob-eerht yaced ot lennahc ni eht mass lavretni 0.21 <
K*@T~T+T-
htiw small snoitubirtnoc gnimoc morf rroa and M2 < 0.31 .4c/2VeG
KRr,
rehgih mass ecnanoser syaced ylno ot sihT ,yaw 3940 ,stneve htiw a noitanimatnoc reppu
K*i?. The K*i?.
tnemirepxe was demrofrep at eht woL -nE timil fo ,%02 erew .detceles sihT laudiser -animatnoc
The
ygre notorpitnA Ring )RAEL( at CERN, using eht noit semoc yltsom morf eht slennahc ’&n-~+rTr-TTr&
XILEBO retemortceps esohw( deliated noitpircsed II( > )1 htiw eno noip deifitnedisim as a ,noak ro
nac eb dnuof ni .feR [ )181 . ehT elohw apparatus is KiK-&m--?rO htiw eno noak gniyaced esolc ot
desremmi ni a citengam ,dleif esohw ytisnetni sehcaer eht xetrev .noiger ehT lennahc htiw all snoip sevig
its mumixam eulav fo 0.5 T gnola its .sixa -orpitnA a htooms ,noitubirtnoc gnisaerced ni eht mass -er
snot htiw a mutnemom fo 200 c/VeM erew deppots noig fo .tseretni ehT noitubirtnoc fo
K+K-T+T-T’
ni a diuqil negordyh tegrat dednuorrus yb a tsrif reyal detalumis stneve ni eht missing mass
K*T?~-+T-
fo 30 niht 1( )mc citsalp ,srotallitnics degnarra ni ,murtceps is nwohs ni .giF la. A esolc tnemeerga htiw
a lerrab and gnidivorp eht noitalihinna semit ot eht dnuorgkcab epahs deniatbo yb eht tif no laer data is
XILEBO thgilf-fo-emit metsys )FOT( . .tnerappa
ehT retuo jet tfird rebmahc (JDC) is detoved ot eht ehT Kf@tiSS~TTSF tnairavni mass noitubirtsid is
gnikcart fo degrahc .selcitrap tI swolla eht -erusaem nwohs ni .giF .bl A tnenimorp signal ni eht mass
stnem fo eht elcitrap mutnemom and fo rieht noiger dnuora 1.4 2c/VeG is .tnedive erehT era owt
dE/dx
and setubirtnoc ot eht noitanimreted fo eht -alihinna seirtne rep ,tneve eud ot eht ecneserp fo owt lacitnedi
noit xetrev and fo eht ygolopot fo eht .tneve ehT -om degrahc snoip ni eht lanif .etats enO nac assume that
mutnem dlohserht no degrahc snoak is 200 .c/VeM eht elbuod degrahc noitanibmoc dedahs(
K&K%*
tuobA 18 noillim stneve erew detcelloc ni 12 .syad aera fo .giF )cl secudorper eht epahs fo eht non
A laiceps reggirt ot tceles a lanif etats htiw at tsael eno tnanoser .noitanibmoc .giF dI shows, rof
K*K%r
degrahc noak [ 191 was deyolpme ni redro ot -itsevni evitartsulli ,sesoprup eht tluser fo eht noitcartbus fo
etag eht lennahc pp -+ K*@ti,,~T~+~-. The sam- eht lairotanibmoc dnuorgkcab morf eht llarevo dis-
elp detsisnoc fo gnorp-4 stneve htiw orez latot ,egrahc ,noitubirt htiw eno yrtne rep ;tneve eht ecnatpecca
all gnitniop ot eht noitalihinna .xetrev noitcerroc has osla neeb .decudortni
ehT eK was ton detceted tub detcurtsnocer yb ehT kaep ecnedive is gnikirts and yrev ralimis ot
1C lacitamenik .tif ehT noitceles airetirc erew desab eht dlo elbbub rebmahc tluser [ 51, tub htiw tsomla
ylniam no eht noitacifitnedi fo eht degrahc noak yb eno redro fo edutingam erom statistics.
dE/dx. ,yltsriF eht noitceles mhtirogla was denut os ehT ecnanoser yaced Dali& tolp is nwohs ni .giF
ot eveihca an tnemeerga >90% htiw thgilf-fo-emit 2a rof eht stneve ni eht mass lavretni 21.38 2c/VeG
,noitacifitnedi a noitcejer no noip >99.9%, and talf fo .giF .bl ylnO eno mra fo eht is ,tneserp as -ve
K*
ycneiciffe fo tuoba %08 as a noitcnuf fo -nemom tnedi osla morf eht and &cK tnairavni mass
K*rr
.mut elcitraP noitacifitnedi was deilppa ot all -rap snoitcejorp .sgiF( 2b and c) . sihT erutaef is a -moc
selcit detceted ni eht lanif ,etats yb gniriuqer eno denib tceffe fo scitamenik and apparatus dlohserht no
190 XJZEBO scisyhP/noitaroballoC Letters 3 361f1995) 187-198
t
GeV/c’ ’c/VeG
M’,(K+‘-n-‘+n’n-) M (K+‘-K%-‘*)
+t++
1
01
1.6 1.1 1.2 1.3 1.4 1.5 I:6
’c/VeG GeV/c’
(M )*‘-r?K+K M( K*‘-Kk-‘*)
.giF .1 derauqS gnissim ssam fo eht -rr+rrr,*K detceles stneve dilos( :)enil eht dehctah area swohs eht stneve detceles yb lacitamenik tif
htiw .L.C > 90% ot eht .lennahc-rr+rrf’rr”K*K ehT epahs fo eht dettif dnuorgkcab noitubirtnoc si osla nwohs suounitnoc( ,)enil saerehw
eht dehsad enil swohs eht -T&~,*K derauqs gnissim ssam rof ~rr-~+rrTK*K etnoM olraC stneve hcihw evivrus eht emas noitceles
airetirc sa eht laer ;stneve )b tnairavni ssam rof yllacitamenik detceles stneve-a+P’r?”K*K owt( seirtne rep :)tneve laer data
Ki?r
dilos( ,)enil ecaps-esahp-n+rrrn”K*K etnoM olraC stneve dettod( ,)enil laer data htiw wol ecnedifnoc level (0.002 5 .LC < 0.01)
dehsad( ;)enil )c tnairavni ssam rof laer data seunitnoc( )enil dna elbuod degrahc noitanibmoc dedahs( ;)aera )d
Kf??r K*@?r* KBn
tnairavni ssam rof laer data retfa eht elbuod degrahc noitcartbus dna ecnatpecca .noitcerroc
K*K%*
noak mutnemom tuc( woleb 200 MeV/c). ,yllautcA a demrof htiw two tnednepedni ,smargorp eno desab no
charged K* si decudorp together htiw a charge -ujnoc the hcameZ rosnet msilamrof [ 201, the other eno no
gated noak dna syaced otni a lartuen .noak nO the -noc the yticileh msilamrof [ 211. riehT stluser were dnuof
,yrart a lartuen K* si decudorp together htiw a lartuen ot eb ni etelpmoc .tnemeerga
,noak dna syaced otni a charged .noak nI the tsrif case, roF the ygrene part of the ,sedutilpma htob -sivitaler
the charged noak gniliocer tsniaga the K* dluow eb cit rengiW-tierB ,snoitcnuf as llew as sedutilpma -noc
too wols ot eb detected yb the ,sutarappa whereas, ni detcurts ni the gnirettacs htgnel ,noitamixorppa eud
the dnoces case, the mutnemom of the charged ,noak ot the tnereffid scitsiretcarahc of the secnanoser -ni
decudorp ni the yaced of the lartuen K*, si evoba the ,devlov were .desu oT dliub the llarevo edutilpma the
noitceted dlohserht dna the tnerap K* can eb detected. gniwollof snoitpmussa were :edam
ehT 3940 detceles stneve were neht dettimbus ot - the ecneserp of eno or erom secnanoser ni the
htob a labolg tif dna a laitrap evaw .sisylana nI the lartuen Ki?r ,metsys hcihw dluoc yaced ot aor,
krowemarf of the rabosi ledom the noitcaer si -disnoc K*I?, (KR)gr, dna (K?r)$, where (KJ?)s dna
ered as a niahc of ydob-owt .syaced gnisU the dettif (Km) s tneserper a nosemid ni .evaw-S ehT -wollof
atnemom-4 of the lanif state, the sisylana was -rep gni noitazirtemarap for the lartuen (KRrr) metsys
OBELJXC ollaboration/PhysicsL ettersB 361 (1995) 187-198 191
z
z 400
6
< 300
cn
2
al 200
5
100
J
0
0.4 0.6 0.6 1 -0.6 0.7 0.6 0.9 1
M”( K*‘-n-‘+) GeV’/c* GeV/c’
M( K+‘-n-‘*)
400 k ,
0.6 0.7 0.0 0.9 1 0.9 1 1.1 1.2 1.3 1.4
GeV/c’ GeV/c’
M(Kw’) M(K*‘-K’)
Rg. 2. a) KIT ztilaD ,tolp )b K*d tnairavni ,ssam )c %K * tnairavni ,ssam )d K*fl tnairavni .ssam roF all snoitubirtsid
(M K*K%rr) > 1.380 .*c/VeG ehT latnemirepxe stniop )sessorc( era desopmirepus ot eht stluser fo eht tseb tif fo eht ytirup-nips
sisylana dedahs( .)saera
and its rabosi noitisopmoced was :desu tnairavni mass is 5.OL ,*c/VeG ti is larutan ot
ehT tnanoser G?jK lartuen metsys and eht tcepxe that eht STAT( ) noitcaretni dluohs rucco
K*
erew debircsed yb a citsivitaler rengiW-tierB ylniam htiw evitaler latibro angular mutnemom 1=
noitcnuf .)WB( 0. gnicudortnI eht notgninneP-nagroM-uA )PMA(
ehT tnemecnahne at dlohserht .giF( )d2 noitazirtemarap fo eht S)TT( ,edutilpma eht data
Ki?
was deifitnedi rehtie htiw eht )089(au ecnanoser noitpircsed devorpmi ,yltnacifingis tub eht tif was
- and erofereht debircsed yb a ettalF alumrof ton tey ,yrotcafsitas ylbaborp eud ot eht tcaf that ni
(F( )au > [ 221, htiw mass and htdiw nekat morf eht wol mass noiger eht gnitsixe stif ot latnemirepxe
eht weiveR fo elcitraP seitreporP [ 231 - ro htiw data era ton yletelpmoc .elbailer
a lanif etats ,noitcaretni dezirtemarap ni A yrotcafsitas tif was deniatbo yb gnicudortni a
(KE)s
eht gnirettacs htgnel noitamixorppa (aS( Kl?) ) . gnirettacs htgnel ,noitcnuf ro yb gnizilareneg eht
evaw-S metsys ( debircsed AMP edutilpma ni eht noitamixorppa [ 251.
The K?T (K?r)s) was N/D
ni eht gnirettacs htgnel noitamixorppa ( OS nI eht tsrif ,esac eht sretemarap erew denimreted
(K?r) )
[241. yb gnittif eht esahp stfihs morf .feR [ 261, ,saerehw
eromrehtruF ti was nees :taht ni eht dnoces ,esac yeht erew denimreted morf ruo
- eht TT& noipid ,snoitubirtsid gniliocer against data. esehT sretemarap erew neht desu ni all eht
dluoc ton eb decudorper ylpmis yb esahp tneuqesbus ,stif gnieb etiuq tnednepedni morf eht
Ki?n-,
.ecaps euD ot eht tcaf that ni this esac eht T&I noitpircsed fo eht KRT lartuen .metsys A elbissop
192 OBELJX Collaboration/ Physics Letters B 361 (1995) 187-198
noitubirtnoc fo p” )-- -r& denrut tuo ot eb -gen A labolg tif fo lanoisnemid& ecaps was .demrofrep
.elbigil neviG a tniop y ni hcus ecaps eht derauqs suludom fo
ehT yratnemele sedutilpma rof pp + E/L dn-- eht latot edutilpma is nettirw as
erew neht detcurtsnoc as :swollof
1. E/L -+ K*l?: INy)12 = c ,~I)Y~JAI (5)
JK
Ak = A(~)BW(E/L)[BW(K**)D(K**)
erehw eht sum is revo all elbissop states, and
pp Jpc
+GdIW(K*‘)D(K*‘)] (1)
A,K(Y) = ~xke”Ak(y),
2. E/L -+ (Kk)gi-:
k
is eht sum fo yratnemele ,sedutilpma htiw x and 4
Ak = AfdBW(&‘~)F(ao)D(ao) (2)
eerf .sretemarap
nihtiW eht ro( )Q xirtam msilamrof [ 271 rof
P
ecnanoser ,noitcudorp eht evitaler phases neewteb -fid
Ak = A(TT)BW(E/L)S~(K~?)D(K~) )3( tneref yaced slennahc fo eht emas ecnanoser era dexif
at eht emas .eulav
3.
E/L + (KT)& Data erew dettif yb eht mumixam doohilekil dohtem
yb gniziminim eht noitcnuf
Ak = A(~)BW(E/L)[S~(K*T~)D(K*~~)
+G. So(Kw>D(K%~)] (4) c = 2- )L(gol
ereH eht E/LA ( ,ytirap-G71-r) is eht D sebircsed evaw-s noipid eht angular ,noitcaretni trap ni G eht is = l([gol~2- i=l _ )f J Yd21)YWI 21)iYWI 1f+ )7(
yticileh ro hcameZ ,smsilamrof gnidrocca ot eht -na
ralug atnemom .noitisopmoced ehT seulav fo angular erehw f sebircsed an tnerehocni esahp ekil-ecaps
mutnemom neewteb and ,noipid and edisni noipid dnuorgkcab .noitubirtnoc Masses and widths fo
E/L E/L
erew ,detcirtser ni eht ,tif ot 0 and 1. erew eerf .sretemarap
tceriD noitcudorp sessecorp ekil pp d nI eht lennahc ecnis eht mass
K*RITT, pp -+ E/L( ITT), E/L
erew osla nekat otni .tnuocca ecniS ni this is hcum retaerg than eht noipid mass, eht )T-Z( -sys
UO~TT,
esac ereht ,era ni ,elpicnirp ynam elbissop angular -om met is ni evaw-s and eht evitaler angular mutnemom
mutnem and nipsosi ,snoitisopmoced yeht erew dedda neewteb eht and eht noipid is osla lauqe ot .orez
E/L
yltnerehocni summing revo all spin .stnenopmoc sihT was deifirev no eht data and brings an tnatropmi
ehT noitanimatnoc morf rehto snoitcaer ot eht :noitacilpmi a O-+ ecnanoser nac ylno emoc morf a
lennahc-,+,=&eK*K ~)%02~( debircsed ,evoba I oS pp etats and a I++ ecnanoser morf a 3 PI jTp .etats
was detubirtsid as esahp :ecaps erofereht ti was as- ehT ygetarts dewollof gnirud eht sisylana was ot
demus ton ot erefretni htiw rehto .sedutilpma sihT -yh kool rof eht muminim tes fo sedutilpma hcihw -orp
sisehtop was dekcehc no laer data yb gnitceles stneve sediv eht tseb noitpircsed fo eht data. ehT tpmetta ot
htiw a wol ecnedifnoc level 200.0( 5 .L.C 5 )10.0 tif eht data yb esahp ecaps plus eht tcerid noitcudorp
rof eht .lennahc-r7+n*meK*K enO nac assume that slennahc was detcejer yb eht
j?p + K*Rmr, aomm
eseht stneve llew tneserper eht dnuorgkcab epahs and .tif oslA eht tif htiw an laixa rotcev ecnanoser was -nu
deedni rieht noitubirtsid denrut tuo tnetsisnoc htiw a .lufsseccus
esahp ekil-ecaps ruoivaheb ees( .giF 1 )b . ehT epahs enO ro erom tnanoser O-+ states ni eht KZ?r metsys
fo eht noitubirtsid llew seerga htiw that deniatbo htiw nipsosi I = 0 had ot eb .decudortni
morf etnoM olraC noitalumis fo eht gnitanimatnoc eerhT rojam spuorg fo stif erew .demrofrep htoB eht
snoitcaer and its evitatitnauq noitamitse is ni doog doohilekil noitcnuf and eht 2X-oduesp detaluclac no a
tnemeerga htiw what deniatbo morf eht stluser fo eht subset fo smargotsih erew deredisnoc as airetirc rof eht
spin ytirap .sisylana ssendoog fo eht .tif ehT detceles smargotsih erew eht
OBEUX Collaboration /Physics L.etters B 36lf1995) 187-l 98 193
tsom evitisnes ot eht nesohc edutilpma -azirtemarap
.noit
)i( nI eht tsrif puorg fo ,stif eht yaced slennahc
r1)089& and erew nekat otni .tnuocca
E/L --+ K+i?
ehT ralacsoduesp-eno ecnanoser sisehtopyh did ton
edivorp a yrotcafsitas .tif
nehW a dnoces ralacsoduesp ecnanoser was -ortni
,decud a gib esaerced ni eht doohilekil noitcnuf tuoba(
0 0
1.1 1.2 1.3 1.4 1.5 I.6 1.1 1.2 1.3 1.4 1.5 1.6
400 )stinu was .devresbo ehT main stcepsa fo eht tif
We4 c&/c' M(Kp'0 G&/C*
stluser erew that eht wol mass etats deyaced ylbareferp Fig. 3. KRrr invariant mass (experimental points) with superim-
ot UO~F, saerehw eht hgih mass etats deyaced ylniam posed the result of the best fit from spin-parity analysis (shaded
ot area) under the hypothesis of E/L + NT, K’a, (K?T)&.
K*k.
,revewoH hguohtla htiw owt secnanoser a -fingis (K&ST with: (a) one pseudoscalar and (b) two pseudoscalar
tnaci tnemevorpmi ni eht tif was ,devresbo data -ed
noitpircs deraeppa ton tey :yrotcafsitas 2x was 3 rof
eht tif htiw eno O-+ and 2 rof eht tif htiw owt O-+.
nI ,ralucitrap a citametsys ycnapercsid neewteb dettif
and latnemirepxe data ni eht mass noitubirtsid
(Ka)
at dlohserht was .devresbo sihT detseggus a tnereffid
noitazirtemarap rof eht metsys ni smret fo a
(Ki?)s
gnirettacs htgnel .alumrof
)ii( nI eht dnoces puorg fo ,stif eht syaced
E/L +
and erew assumed. ehT stluser era -er
(KZ?)sr K*Z? w(cos6) rod w(cosd) rod
detrop ni elbaT 1.
ehT gnirettacs htgnel ni evaw-S was a eerf -ap Fig. 4. Decay angular distribution of: (a) E/L recoiling against
Kk?
the dipion in the pp rest frame and h) one pion recoiling against
retemar and ti denrut tuo ~Ku = 5.0- f 0.1 .‘-VeG
the (Kt?) system in the E/L rest frame; superimposed is the result
euD ot eht smallness fo this ,rebmun this edutilpma
of the best lit for two resonances (shaded area).
tonnac eb deterpretni as gnirrefer ot eht a~( )089 -ser
.ecnano (L/E/)~(L/E )1 N 0.4.
ecnO erom ereht was a tnetsisnoc tnemevorpmi fo )iii( ,yllaniF ni eht driht puorg fo ,stif eht -idda
eht tif nehw a dnoces ecnanoser htiw was lanoit ( yaced edom was :decudortni
Jpc = OF+ KGT)& E/L -+
,decudortni as nac eb nees morf elbaT 1.
agr,K*R, (K?r)$, (KE)p
tI is gnitseretni ot eciton that, yltnednepedni morf stluser era nwohs ni elbaT 2 and Figs. 3 and
The
eht noitpircsed fo eht metsys )089(a( ro 4. A gib ecnereffid ni eht doohilekil neewteb eno and
Ki?
(OS ot ebircsed eht yaced fo eht wol mass -uesp owt states, hcihw yaced yltnanimod ot and
Ki?) ) (K?r) sR
,ralacsod eht hgih mass ecnanoser ,syaced ni htob ot ,ylevitcepser nac eb .devresbo ecniS eht wol
K*R,
,sesac ylno ot K*R. snoitcarF era etiuq ,elbats as llew ygrene (K?r) s metsys is ton ,tnanoser eht E/L yaced
as masses and widths. edom ot ( is yllacitcarp tnelaviuqe ot eht -eerht
K?r) SK
nI redro ot tset rehtehw eht is ,decudorp ni pjj ydob tcerid .yaced ehT emas nac eb said fi eht
E/L (KIT)
at ,tser ton yleuqinu morf laitini ,etats laitini dlohserht tnemecnahne is ,debircsed ton yb a
pp ‘SO (KR)s
1S3 and lP3 states erew osla .deredisnoc A slight -mi ecnanoser ,)~a( tub yb a gnirettacs htgnel ,edutilpma
tnemevorp ni eht doohilekil was devresbo and, as -xe ni hcihw eht gnirettacs htgnel sekat a small .eulav
,detcep eht 1S3 and lP3 snoitubirtnoc denrut tuo ot eb ,eroferehT eht yaced edom ( and
KT) SK (KK) gr are
desserppus htiw tcepser ot OS* : OS‘ - ,%48 IS3 N deedni ,tnelaviuqe as detacidni yb a nosirapmoc fo eht
,%6 and .%01 ehT noitcudortni fo eseht -ini tif stluser nwohs ni elbaT 2 (last owt .)stif
3P1 N
lait states decuder ylthgils eht dnuorgkcab ,noitcarf tceriD ydob-eerht ,syaced ro ,ydob-owt-isauq ni
hcihw detluser .%51- On eht rehto hand, eht evitaler hcihw eht rabosi is a ylkaew gnitcaretni metsys (as
thgiew fo eht owt secnanoser deniamer ,elbats htiw rof ecnatsni eht JT ( )TV s ,)metsys erew osla ,devresbo
the
0.03 0.02
f &
with Back- ground 0.38 f0.03 0.27 f0.02 0.22 f0.02
GeV/cz),
Background 0.20 0.23 in ?rrr
i
are K’
GeV/c*), 0.03 0.03 0.04 f0.02 - 0.07 f0.03
in zt f
Kmr
widths
are K’ 0.11 0.05
and r
0.098 f0.014 0.108 f0.014
widths 0.014
and f (masses m
I- 0.108 E/42) _ 1.450 f0.006 1.466 f0.007
v
(masses Nf. W)s
resonances K 0.01
0.007 ( - <
f O-+
resonances Nf. E/L(~) m _ 1.466 two parameters K?r)st 0.01
O-+ and fitting ( - < -
two parameters *i? f 0.03 of one of K*R
and fitting K _ 0.22 number - - 0.20 f0.05 0.15 f0.04
one of + the
0.01 0.01
of hypotheses
0.01 and E/d3 ogr - < <
number E/L@) (Kg)slr - < the
in
the hypotheses and the f 0.004 f 0.004 (Ki?)sw, pseudo-x2 I- 0.056 f0.006 0.046 f0.005 0.052 f0.004
the
in s,
K*R, pseudo-X* l- 0.078 0.052 (Kn-)L, E/41) m 1.410 f0.002 1.414 f0.002 1.416 f0.002
g~, L, the 0.002 K’R, function &r
(Kf?) f qvr, (K - - 0.49 f0.06
L -t E/ function E/L(l) In 1.426f0.002 1.416 E/ L --) likelihood Kr)st
( 0.30 f0.06 0.44 f0.07 -
from the fits with of the maximum likelihood E/b(l) 4 (KK)s7r K*i? KB) SV, K* R) 0.23 f0.03 0.461tO.03 K&T, K*a) 0.47 f0.04 < 0.01 from the fits with values of the maximum E/41) - aorr K*W a,pr, K*R, (KT)& 0.23 0.04 f0.02 f0.05 aor, K*t, ( KT) $) 0.09 < 0.01 f0.04 K*K, (K@sT) 0.04 0.02 f0.02 f0.01
Table 1 Fractional contributions corresponding values Nf L X2 ( ( one-resonance fit 2.6 7 -2420 IWO-resonancefir ((-2630 1.3 12 Table 2 Fractionals contributions with the corresponding Nf L X2 one-resonancefit ( -2310 2.6 6 two-resonance fit ( -2606 1.3 11 two-resonancefir (aorr, -2660 1.3 14
OBEUX Collaboration/ Physics Letters B 361(1995) 187-198 195
nehw hcus edutilpma was nekat ylticilpxe otni -ca
,tnuoc ni ordah noitcudorp ssecorp 1281 as llew as ni
J/(cl yaced [ 161.
enO rojam noitaredisnoc morf selbaT 1 and 2 is that
eht dnoces ralacsoduesp syaced yltnanimod ot
K*R,
etiuq yltnednepedni morf eht yaced fo eht tsrif .etats
ehT noitubirtnoc fo a +fI ,ecnanoser htiw mass
and htdiw ralimis ot that detroper yb eht MARK III
noitaroballoC [ 151, did ton evorpmi eht ytilauq fo eht
.tif ehT reppu timil rof eht ecneserp fo hcus ecnanoser
denrut tuo ~2.5%.
ehT emas nac eb said rof elbissop snoitubirtnoc
morf rf ( )5821 ro/dna q ( ))0921 hcihw did ton -ortni
ecud stnemevorpmi ni eht .tif
ehT tif stluser htiw G = - 1 erew hcum reroop than
esoht htiw G = +l, os that eht E/L ytirap-G was dexif -
ot +l ni eht .sedutilpma 0 1 53 ,““,,,j’,,‘,’ 41 1 45 SI 0 53.1 I-““““““ 41 1 54 51
nI eht ,selbat as dnuorgkcab era detacidni all -nu M(KK”) C/V& U(YKn) &v/c’
detnuocca tnanoser-non snoitubirtnoc ot eht detceles .giF 5. stluseR fo eht laitrap evaw :sisylana laitrap evaw seitisnetni
dna dnuorgkcab .noitubirtnoc
,lennahc plus eht noitanimatnoc morf rehto gnitepmoc
snoitcaer gnideef hguorht eht noitceles .airetirc -eroM
,revo eht snoitairav devresbo ni eht dnuorgkcab -netni ylno eno yrtne rep ,tneve eht dnuorgkcab ,gniniatnoc
ytis ni eht tnereffid gnittif sesehtopyh era ylbamuserp ni this ,esac osla eht lairotanibmoc .noitubirtnoc
eud ot snoitubirtnoc morf detnuoccanu small -opmoc Using a tes fo gnirefretni ,sedutilpma eht -isnetni
stnen fo eht .edutilpma ehT ecnedicnioc fo a doog ,seit as llew as eht evitaler phases, erew detamitse htiw
doohilekil htiw a wol eulav fo eht dnuorgkcab hcihw( a mumixam doohilekil tif rof tnereffid mass
(KI?v)
denrut tuo ylthgils rehgih than eht noitanimatnoc -moc .slavretni ylnO eht tnanimod laitini etats and
pp ‘&
gni morf rehto )snoitcaer is an noitacidni that eht tsom an tnerehocni dnuorgkcab detubirtsid as esahp ecaps
tnatropmi sevaw erew yltcerroc nekat otni .tnuocca erew nekat otni .tnuocca ehT seitisnetni erew -uclac
An tnatropmi scitsiretcarahc fo eht detceles detal morf eht evitaler snoitcarf fo hcae yratnemele
lennahc-r7&rr7cKfK is that ereht era owt -ibmoc ,sedutilpma htiw eht latot sum dezilamron ot eht -mun
snoitan gnitubirtnoc ot eht ,metsys eud ot eht reb fo stneve ni eht nevig mass .nib
(KR?r)
ecneserp fo owt lacitnedi .snoip fI eno stolp eno -moc nI redro ot niatbo a elbats noitulos against -issop
noitanib against eht ,rehto owt lacitamenik snoiger nac elb seitiugibma ni eht gninnib ,erudecorp eht sisylana
eb :dehsiugnitsid eno erehw eht masses fo htob -moc was deirrac tuo rof tnereffid gnippalrevo-non mass nib
snoitanib llaf htob ni eht tnanoser noiger ( 05.1-73.1 ,sezis gniriuqer a htooms knil fo eht evitaler phases
,)2clVeG and rehtona erehw ylno eno noitanibmoc neewteb gniruobhgien mass bins.
is ni eht noiger fo tnanoser ruoivaheb ereht( era owt ehT ytisnetni fo hcae laitrap evaw is nwohs ni .giF
hcus gnippalrevo-non .)snoiger ehT tnaveler -manyd 5. As ,detcepxe eht dnuorgkcab ytisnetni noitubirtsid
sci devresbo ni ruo lanif ,etats .e.i eht ecneraeppa fo had a epahs ralimis ot eht lairotanibmoc dnuorgkcab
and eht dlohserht tnemecnahne ni eht mass eno elbuod( degrahc .noitanibmoc ehT
K’ KI? K*K%*)
,noitubirtsid era yllacitamenik desserppus ni eht -revo kaew O-+u~7r evaw ytisnetni demees osla ton ot
lapping .noiger sihT erutaef was nekat otni tnuocca evah yna elbakramer erutcurts and ti was ralimis ot
ni a laitrap evaw sisylana )AWP( : yb gnimrofrep a eht epahs fo eht lairotanibmoc :dnuorgkcab rof that
tif fo eht data using esoht stneve fo a nevig nosaer this evaw was nesohc as eht ecnerefer .evaw
(KKr)
mass nib hcihw degnoleb ylno ot eht gnippalrevo-non ehT (+-O evaw ytisnetni dewohs a kaep ni
Kr)sR
mass .snoiger nI this ,esac eht edutilpma desu eht noiger fo 1.4 ,2c/VeG elihw eht O-+
(KRa) K*R was
rof eht tif is llew elbatius ot ebircsed a metsys htiw erom tnenimorp at rehgih mass seulav dnuora( 1.45
196 scisyhP sretteL
OBELJX Collaboration/ B 361 (1995)1 87-198
depo sisylana ,smargorp doog ecnedive rof eht -sixe
ecnet fo owt secnanoser ni eht mass noiger fo eht
E/L
nosem was ,deniatbo htob secnanvser gnieb yletinifed
dehsilbatse ot eb .sralacsoduesp
ehT lennahc noitcaer sdeecorp yltsom morf ,&l -ini
lait :etats eht evaw-P noitubirtnoc denrut tuo ot eb on
erom than .%01- ehT lennahc is detanimod yb -oser
nant noitcudorp 08( ot .)%09
gninrecnoC eht wol mass ,ecnanoser eht tif htiw a
small evaw-S gnirettacs htgnel was yletinifed -teb
Ki?
ret than eht eno htiw eht an .ecnanoser ,revoeroM osla
a ecnanimod fo E/L + ( KT)sL?, and again a small
0
noitubirtnoc fo r7au was .dnuof euD ot eht smallness
fo and gnirettacs ,shtgnel and ecnis and
a,K aKr Kn-
-1
mass artceps revoc a detimil mass noiger -trats
1.4 1.425 1.45 1.475 1.5 Kg
gni morf ,dlohserht eht yaced slennahc and
M(KK5r) GeV/c' (KZ?)sn-
( nac eb deredisnoc tnelaviuqe and yrev -imis
K?T)s~
.giF 6. esahP noitom fo eht +-O ?I*K .evaw
ral ot a esahp ekil-ecaps .ruoivaheb sihT snaem that eht
wol mass ecnanoser smees ot yaced ylniam ot
Kkv,
.)2c/VeG A tif fo eseht seitisnetni htiw rengiW-tierB ylbissop htiw lanif etats ,snoitcaretni htiw a small -noc
sedivorp stluser ni tnemeerga htiw esoht fo eht labolg noitubirt gnimoc morf ,TQU and a elbigilgen eno morf
tif 2)1( = 1.403 f 0.006 and r = 0.04 f 0.01 ,2clVeG Mass and htdiw era m = 1.416 200.0f 2c/VeG
K*i?.
m = 64.1-44.1 and r = 021.0-660.0 .)*c/VeG and r = 0.050 f 0.004 .2cfVeG
nI eht noiger 34.1-83.1- 2c/VeG the phase noitom gninrecnoC eht rehgih mass ,ecnanoser stluser erew
fo eht (+-O )TIK sR evaw htiw tcepser ot eht rr~u+-O etiuq ,elbats gnitacidni a tnanimod yaced ot htiw
K* R,
evaw detluser tsomla ,tnatsnoc hcihw snaem that htob an ytisnetni yletamixorppa -2/l 3/l fo eht tsrif -oser
sevaw era gnitanoser ,rehtegot ro that envn is -tanoser .ecnan Mass and htdiw era m = 1.46 & 0.01 ’c/VeG
.gni morF eht ecnetsixe fo a raelc tnemecnahne -bo and lY = 0.105 f 0.015 .2c/VeG
devres ni eht (+-O ?is)rrK ,ytisnetni eht tsrif -ehtopyh Masses, widths and yaced sedom era ni tnemeerga
sis smees erom ,elbaborp .e.i a tnanoser ruoivaheb fo htiw eht sisylana fo J/$ evitaidar yaced demrofrep yb
htob sevaw nac eb .deugra ,deednI morf eht labolg ,tif eht Mark III noitaroballoC [ 151.
a small tnanoser noitubirtnoc morf eht r?ca+-O evaw tnanimod ydob-eerht yaced edom fo eht rethgil
The
was .devresbo O-+ is devresbo ereh rof eht tsrif .emit lanoitiddA
ehT esahp fo eht ?Z*K+-O evaw evitaler ot eht snoitubirtnoc morf tcerid noitcudorp snoitcaer pp 4
~Q‘-O evaw shows a dipar drawrof noitom .giF( K’ Kmr and aomm denrut tuo ot eb yrev small.
)6 ni eht emas mass noiger erehw eht ytisnetni fo ehT stluser fo eht laitrap evaw sisylana erew sub-
eht evaw has a kaep dnuora( 64-l-44.1 yllaitnats ni tnemeerga htiw esoht fo eht labolg .tif
O-+K*R
.)2c/VeG sihT sedivorp a raelc noitacidni fo eht ehT esahp noitom fo eht O-+ K*R evaw demrifnoc
ecneserp fo a ecnanvser ni that .evaw eht ecnetsixe fo a dnoces ralacsoduesp etats ni pp -na
ehT tluser fo PWA is that ereht is a tnanoser -curts noitalihin at .tser
erut ni eht mass noiger dnuora 1.4 2clVeG htiw erehT is on noitacidni ni eseht data fo eht ecneserp
KNIT
a main yaced edom (Kz)&, rehtegot htiw a dnoces fo a elbissop 1+ + ,etats as ti dluohs eb ,detcepxe eud ot
,ecnanoser gniyaced vt K*R, at rehgih mass seulav eht muinotorp evaw-S ecnanimod ni Bp noitalihinna
64.1-44.1( .)*c/VeG at tser ni .2HL
nI ,noisulcnoc morf eht tif fo 3940 pp noitalihinna sesylanA fo rehgih statistics data samples era
ni diuqil negordyh otni eht lanif etats :dedeen ni redro ot yfitnauq eht small snoitubirtnoc
K*~T~T+IT-,
- a data elpmas gnideecxe suoiverp data ni KRTT yb a fo rlna and K’R ot eht tsrif ecnanvser yaced and ot
rotcaf xis - demrofrep htiw owt yltnednepedni -leved niatbo a erom esicerp noitaulave fo mass and htdiw