STRANGENESS PRODUCTION IN ANTIPROTON ANNIHILATION AT REST ON 3He

38 Pages·2002·1.75 MB·English

raelcuN scisyhP 625A )1991( 254-514
dnalloH-htroN
SSENEGNARTS NOITCUDORP NI NOTORPITNA NOITALIHINNA AT
REST ON 3He, 4He AND *‘Ne
.F ,’ARTSELAB .A.uY ,’VOSUTAB .G ,4~31LOICSIDNEB .S ,6*SOCSALOSSOB .O.F ,’KIVIERB
.P.M ,6*5ASSUB .L ,6,50SSUB .M.K ,’NESLEINAD .C ,’ODLARAUG .V.I ,’NIKMOLAF
.L ,6,5AVAF .L ,“,50RERREF .V ,+31NIPPILIF .A ,?FUTAAH .A ,’DILSNIETSLAH
T. ,’NESBOCAJ E. IDOL ,“*61NIZZIR .A ,sAROIGGAM .K ,FSOBELKYM .M.J ,9NESLO
.D ,‘=IREIZNAP .G ,6~SONIGARIP .B.G ,*OVROCETNOP .A ,4*31DNOTOR
.M.A ,2YKSNEVTSEDHZOR .P ,?NIVLAS .G.M ,’VOKINHZOPAS .O.S ,’NESNER@S
.F ,6TSOLLESOT .I.V ,’KAYTERT .A 4,31NOILGANEV dna .A ”~41NONEZ
’ Dipartimento di ezneicS ,ehcisiF atisrevinU di Cagliari, I-09100 Cagliari, Italy
and
NFNI - Sezione di Cagliari, I-09100 Cagliari, Italy
’ Joint etutitsnI for Nuclear ,hcraeseR Dubna, SU-101000 Moscow, RSSU
3 Dipartimento di acisiF Nucleare e Teorica, atisrevinU di Pavia, I-27100 Pavia, Italy
4 NFNI - enoizeS di Pavia, I-27100 Pavia, Italy
5 otutitsI di acisiF Generale “‘A. Avogadro”, atisrevinU di Torino, I-10125 ,niruT Italy
6 NFNI - enoizeS di Torino, I-10125 ,niruT Italy
’ scisyhP Department, ytisrevinU of ,olsO N-0316 Oslo 3, Norway
a Laboratori Nazionali di Frascati dell’lNFN, I-00044 ,itacsarF Italy
’ scisyhP Department, ytisrevinU of ,negreB N-5007 ,negreB Norway
i” Dipartimento di Automazione ,elairtsudnI atisrevinU di ,aicserB I-25100 ,aicserB Italy
,PE/NREC ii CH-1211 Geneva 23, dnalreztiwS
devieceR 51 hcraM 0991
desiveR( 02 enuJ )0991
:tcartsbA weN atad era detroper no notorpitna snoitalihinna ta tser htiw noitcudorp fo A dna ,iK gnisu
a remaerts rebmahc htiw ,eH3 eH4 dna eN“ sa sag .stegrat ehT atad edulcni ,A ,iK :KA dna
gKiK noitcudorp setar dna mutnemom ,snoitubirtsid -n mutnemom ,artceps naem srebmun fo
degrahc selcitrap yllareneg dna fo ylevitagen degrahc selcitrap yletarapes rof tnereffid noitcaer
.slennahc ehT sdleiy era derapmoc ot elpmis lairotanibmoc snoitaluclac desab no eht emertxe
snoitpmussa fo A noitcudorp aiv B = 1 ro aiv B = 0 (K )gnirettacser .snoitalihinna A dna gK
mutnemom artceps era derapmoc ot ledom elpmis snoitaluclac erehw B = 0 dna B = 1 snoitalihinna
htiw dna tuohtiw etats-lanif snoitcaretni era .deredisnoc A weiver fo gnitsixe atad no A dna gK
noitcudorp si ,detneserp gniwohs eht ecnedneped no eht p mutnemom dna no eht ssam rebmun
fo eht .tegrat
RAELCUN SNOITCAER ,eH4,3 eN“ ,rab-p( X), E ta ;tser derusaem noip mutnemom
E ,artceps ssenegnarts ,noitcudorp degrahc elcitrap naem .srebmun saG ,stegrat demaerts
.rebmahc
1. Introduction
A process hcihw stisoped elbaredisnoc ygrene otni the suelcun si the noitprosba
of na .notorpitna taerG tseretni has neeb attached ot the elbissop act that, rednu
05.30$/19/4749-5730 @ 1991 - reiveslE ecneicS srehsilbuP .V.B )dnalloH-htroN(
May 1991
416 .F Balestra et al. / Strangeness production
etairporppa ,snoitidnoc a noitcelloc of snoelcun dluoc eb demrofsnart otni a -krauq
noulg amsalp .)PGQ( nA evisnetni search for the PGQ phase si gnieb enod ni
citsivitaler noi-yvaeh noisilloc stnemirepxe at nevahkoorB dna CERN.
ehT noitprosba of p ni ielcun ecudorp yllaitini a erom dezilacol toh“ spot” dna
eno thgim ask whether the metsys yltneuqesbus passed hguorht the PGQ phase.
ikslefaR ‘) has deugra that the egral A ”Z+ noitcudorp cross noitces devresbo ni
P - aT‘“ snoitcaer at 4 c/VeG [ref. I)‘ stcelfer dloc PGQ .noitamrof ,revewoH ti has
netfo neeb detniop ,tuo for ecnatsni yb nonguC et .la 3), that ssenegnarts -ecnahne
stnem are ton ylirassecen serutangis of PGQ ,noitaerc tub rucco osla ni a lanoitnevnoc
cinordah erutcip ecno eno sedulcni noelcunitlum noitprosba .snoitcaer
nihtiW a erom lanoitnevnoc mrof the elcitrap-egnarts noitcudorp woleb the i;ii
dlohserht ni ielcun si detagitsevni )7-4 yb snaem of a epyt-edacsac ledom where the
noitalihinna si deredisnoc ot rucco no a elgnis noelcun (B = 0), dna where the
noitareneg of rr, ,n w dna snoak si dewollof yb the tneuqesbus gnirettacser of these
selcitrap no the laudiser .snoelcun B = 0 noitalihinna secudorp ssenegnarts ni a
tcerid yaw hguorht KK sriap .ylno
gnirettacseR swolla /”K +K or /‘?I -K charge ,egnahcxe tub swolla osla the -rofsnart
noitam of -K/og otni snorepyh Y N’K( + YX or N-K + YX), so ni noitiidda ot
Kk sriap gnirettacser swolla noitcudorp of YK .sriap ,revoeroM gnirettacser of
other selcitrap sesaercni tahwemos the latot elcitrap-egnarts ,dleiy ylniam eud ot
wN gnirettacser 6).
noitalihinnA no erom naht eno noelcun (B > 0 )noitalihinna nac osla ecudorp
KK dna YK ,sriap dna the latot elcitrap-egnarts dleiy si rehgih ni siht lennahc naht
ni the B = 0 case erofeb gnirettacser ‘). roF B = 1 snoitalihinna at rest, ref. )“ stciderp
that the egnarts selcitrap are decudorp at a rate of 17.1% derapmoc ot 4.7% for the
B = 0 .snoitalihinna ,revoeroM ni the snoitalihinna no 3He dna 4He evoba 400 MeV/ c
the B = 1 snoitalihinna dluohs evig a rate of tuoba 10% [ref. .I)“ A ytilibaborp of
the emas edutingam smees ot emoc tuo of stnemirepxe htiw snoitalihinna at rest
no muiretued 9*10).
Of ,esruoc gnirettacser nac rucco osla after B = 1 ,snoitalihinna htiw ralimis effects
as those debircsed for B = 0 case. nI yna case, the ecneserp of snorepyh gnoma the
lanif stcudorp of notorp-itna suelcun snoitalihinna ni siht ygrene noiger slaever that
processes tsixe hcihw evlovni erom naht eno .noelcun ,snoaK no the other ,dnah
nac osla eb detareneg ni processes no elgnis .snoelcun
sihT paper si dednetni ot etubirtnoc ot the gnidnatsrednu of the noitcudorp of
iK dna )’2(A ni snoitalihinna of notorpitna at rest no 3He, 4He dna *‘Ne .ielcun
nI ralucitrap we llahs redisnoc soitar ekil
N(A) + )O’GN N(A)+N(E’) NWO,)
=
R = ),OK(N ’ R A = citsaleni(N )stneve ’ g,R citsaleni(N )stneve ’
hcihw dluohs etacidni the evitaler ecnatropmi of the noelcunitlum processes. roF
erup B = 1 snoitalihinna at rest the oitar R has neeb detamitse ot eb 1.46 [ref. .I)“
F. Balestra et al. / Strangeness production 417
roF B = 0 noitalihinna sulp gnirettacser the oitar R has neeb detamitse ot eb 1.10
for C21 woleb 400 MeV/ c dna 1.43 for 20Ne at 600 MeV/c [ref. .I)“
erehT evah neeb yllaitnesse xis stnemirepxe gnitagitsevni egnarts elcitrap -cudorp
noit ni p snoitcaer no ielcun reivaeh naht :muiretued onayiM et al. at VeG4 no
aT‘“ ni a elbbub rebmahc at KEK [refs. ,])“*2 the SP 179 noitaroballoc at 0.6 c/VeG
no 20Ne dna 4He ni a remaerts rebmahc at ,RAEL CERN [refs. ‘2,‘3)], odnoC et al.
at 4.0-0.0 c/VeG no ,C ,T aT dna bP [ref. 14)], htimS et al. at rest no C dna U
[ref. I)“ nimraB et al. at -3.0 1.05 /VeG c dna at rest no 13’Xe [ref. ])”I dna XIRETSA
at rest no 14N [ref. .I)“
nI ref. )2i we detneserp stluser no lartuen elcitrap-egnarts noitcudorp ni -alihinna
snoit of p no eN“ at 607 MeV/c. nI siht work we dnetxe the sisylana ot edulcni
X+’V+eN“+p at rest
X+oV+eH4t-p at rest
X+oV+eH3+p at rest
where V” = )“;Z(A or .gK
ehT latnemirepxe sutarappa detsisnoc of a detnuhs-fles remaerts rebmahc ni a
citengam dleif dna was exposed ot the p smaeb of RAEL ytilicaf at CERN. ehT
sliated of the sutarappa dna sti ecnamrofrep are reported ni ref. .)*I ehT rebmahc
has a evitisnes emulov of 70 90 18 .3mc ehT citengam dleif was 0.5 T (20Ne) dna
x x
0.4 T (4He dna 3He). ehT maeb was degraded morf 105 MeV/c nwod ot 16~ MeV/c
ot ekam the p stop ni the lartnec noiger of the gas target.
ehT paper si dezinagro as :swollof sect. 2 si detoved ot the A dna iK .sdleiy nI
sect. 2.1 we etaulave the seulav of ,,R g,R dna R for 3He, 4He dna 20Ne at rest dna
ni sect. 2.2 the sdleiy of AgK dna gKiK .stneve nI sect. 2.3 we erapmoc ruo data
htiw the elohw dlrow set of ralimis data at rest dna ni .thgilf ediseB A dna zK
,sdleiy siht weiver sredisnoc naem seulav of ,atnemom seitidipar dna gnorp -itlum
.seiticilp nI sect. 2.4 we ekam na sisylana of data desab no elpmis snoitpmussa ni
order ot see whether the data are tnetsisnoc htiw A gnieb decudorp ni erup B = 0
or B = 1 .snoitalihinna
Sect. 3 si detoved ot the mutnemom spectra of ,A gK dna -n dna ot charged
selcitrap .seiticilpitlum nI sect. 3.1 we show the mutnemom snoitubirtsid of ,A iK
dna rr decudorp( ylniam ni noitalihinna stneve tuohtiw )ssenegnarts no 3He, 4He
dna 20Ne at rest. nI sect. 3.2 we ecudortni elpmis sledom ot esylana the data.
2. A and Kz yields
2.1. MEASUREMENTS OF R,, RK; AND R
A dna gK were devresbo hguorht rieht charged yaced :sedom
A + -np (64.1%) , +,OK Y+rr (68.6%).
418 F. BAlestrA et al. / Strangeness production
Each noitalihinna htiw at tsael eno detaicossa ”V etadidnac was ylluf derusaem
dna processed hguorht the ardyH yrtemoeg dna citamenik .margorp No noitcnitsid
dluoc eb edam neewteb A dna JZ”. nI order ot tceles neewteb A dna gK we esu the
gniwollof noitceles :airetirc
(a) nI the case of ytiugibma neewteb A dna gK we tceles the sisehtopyh htiw the
tsehgih ytilibaborp of the citamenik .tif sihT dohtem was desu ni p 4He dna p 20Ne
.ylno
)b( roF p 3He we do the ,noitceles revenehw ,elbissop gnidrocca ot noitasinoi or
noitcudorp of a .noretued noitcnitsiD neewteb ,snoretued snotorp dna +-G si elbissop
ni ‘He dna( 4He, ref. ))“‘ for tracks htiw atnemom 054~ MeV/c dna pid elgna .”04~
Note that fi a noretued d si decudorp ni p 3He + d X, neht X tonnac niatnoc a A
eud ot noitavresnoc of noyrab .rebmun ylralimiS ni p 4He ,-- 3He X hcihw are neve
gnorp ,stneve dna p 4He + 3H X (odd gnorp ,)stneve X tonnac niatnoc a .A
ehT noitceles noiretirc (a) decudortni a dnuorgkcab of A )zK( ni the )A(gK .elpmas
nI order ot etamitse siht dnuorgkcab a etnoM olraC margorp was edam where
eniuneg A dna zK are detrotsid gnidrocca ot the errors gnimoc morf the ardyH
yrtemoeg .margorp ehT A )gK( elpmas was nekat morf the dettif )iK(A .stneve ehT
detrotsid A dna gK are yltneuqesbus processed hguorht the ardyH citamenik
margorp ni the emas yaw as the latnemirepxe .stneve ehT ytilibaborp of gnitceles
the gnorw sisehtopyh hguorht noiretirc (a) snrut tuo ot eb .%01~ ,revewoH the
snoitcerroc yrassecen ni ,R ,R dna ;KR nrut tuo ot eb tuoba 2% or ,ssel ecnis the
rebmun of stneve derrefsnart morf A ot gK si tuoba the emas as that derrefsnart
morf zK ot .A
morF .gif al dna .gif bl we see that there si a laitnatsbus ssol ni V” stneve htiw
short yaced shtgnel here .nwohs sihT si eud ot dab ytilibisiv raen the yramirp .xetrev
gnisU the latnemirepxe mutnemom spectra tuohtiw( stuc ni yaced )htgnel together
htiw the rebmun of stneve htiw yaced htgnel >L 1 mc we nac etamitse noitcerroc
factors =X N,,,/N,,, ot eb (1.76kO.25) (A) dna (1.60*0.20) )tK( for 20Ne, (1.765
0.15) (A) dna (1.63kO.13) $’K( for 4He dna (1.85kO.15 )A( dna (1.63kO.13) )gK(
for 3He. ehT( dashed senil ni .gif al dna .gif bl evah neeb detaluclac gnisu the
corrected latot rebmun of stneve N,,, dna the latnemirepxe mutnemom spectra of
A dna .)gK sihT dohtem thgim dael ot a citametsys noitamitserednu of the latot
rebmun of stneve eud ot a elbissop kcal of wol mutnemom stneve ni the latnemirepxe
mutnemom spectra. ,revewoH ni order ot etagitsevni siht ,rehtruf we yrt ot etamitse
X yb gnisu sledom (see sect. 3).
nI .gif b91 dna .gif 17a we evah derapmoc the latnemirepxe mutnemom -ubirtsid
snoit of A dna zK htiw ledom .snoitciderp nI the latnemirepxe data we evah edam
a tuc at 1 mc ni the yaced ,htgnel dna the ledom snoitciderp are dethgiew .ylgnidrocca
ehT ledom secudorper the mutnemom snoitubirtsid ylriaf ,llew dna we etamitse X
ot eb 1.85kO.04 (A) dna 1.71*0.04 ,)gK( tnetsisnoc htiw seulav of X nevig .evoba
nI elbat 1 we tneserp the latot rebmun of snotorpitna N,, the rebmun of stneve
detected, the rebmun of stneve htiw L > 1 mc dna the corrected srebmun N,,, . yllaniF
.F artselaB te .la / ssenegnartS noitcudorp 914
0 2 4 6 a 10 12 14 1 htgnel6 3
yaced cm
(b)
125
100
75
50
0 0 2 4 6 a 10 12 14 16 3
htgnel
decay mc
.giF 1. )a( noitubirtsiD fo yaced shtgnel rof A ni .eH4 (b) noitubirtsiD fo yaced shtgnel rof gK ni .eH4
diloS :enil ;tnemirepxe dehsad :enil .detaluclac
TABLE 1
Total number of antiprotons ND and number of produced A and Kg in p 3He, p “He and p *‘Ne at rest:
)a( oN yaced htgnel )L( ,tuc (b) >L 1 ,mc )c( srebmun fo A dna iK detcerroc rof ssol ni rebmahc
p
3He at rest f, 4He at rest p *‘Ne at rest
ND LN cOm L(cbm1 ) Corr. ND L NcOu t L(c>ml ) ‘2x1. ND LN C”t O L(cm) b-1 .noc
N(A) 14319 28 27 5019 72645 292 268 472*49 30364 103 87 153127
NW:) 101 96 156* 16 325 295 481*47 93 85 136*25
024 .F Balestra et al. / Strangeness production
snoitcerroc for lartuen yaced sedom of A dna ,zK elbarusaemnu stneve (9%), gnorw
snoitulos )%2~( dna gninnacs ycneiciffe (98%) are nekat otni tnuocca ot evig the
stluser detneserp ni elbat 2.
2.2. ;K;K DNA ;KA SDLEIY
nI p 4He snoitalihinna at rest, where the scitsitats are ,tsehgih we dnuof 42 stneve
htiw 2 elbisiv V”: ,gKA72 gKgK9 dna .AA6 tsriF we eciton that the rebmun of AA
stneve si tnetsisnoc htiw the %01- gnorw snoitulos gnimoc morf the citamenik tif
.noitceles eroferehT we redisnoc the AA stneve ot eb .,”KA retfA noitcerroc for
gnorw snoitulos we evah 11 gKgK dna 3 1 A EK .
.3.2 NA LATNEMIREPXE REVIEW
A weiver of gnitsixe data no R, R,J dna R Kg where iK dna A are decudorp ni
suelcun-p snoitalihinna are nevig ni elbat 3 together htiw the gnidnopserroc seulav
morf pp dna pd .snoitalihinna hguohtlA the data no elcitrap-egnarts noitcudorp ni
p suelcun snoitalihinna are rather detimil we nac ekam the gniwollof snoitavresbo
morf elbat :3
2.3.1. Annihilations at rest.
(a) A :noitcudorp
)i( R, si tuoba 1% nehw A> 4.
)ii( R,(A34)> >)eH3(,R R,,(‘H).
)iii( R, (A 3 4) si tuoba 3 semit Rn (2H).
ehT errors are too egral ot enimreted how R,, sdneped no A for A > 4.
)b( iK :noitcudorp
)H‘(;kR - )H*(;,R > R,$3He) > R,$4He) > Rg(“Ne) .
ehT rewol seulav of R,, dna R for *H dna 3He yam tcelfer that these ielcun evah a
esool erutcurts ni ruovafsid of gnirettacser ro/dna noelcunitlum .noitalihinna nI
TABLE 2
dleiY fo A dna gK rep( ,)ji R,(%), R&%) dna gK/A oitar (R) ni p ,eH3
p eH4 dna p *‘Ne ta tser
p eH3 ta tser p eH4 ta tser p eN“ ta tser
R 53.0 i 80.0 61.0*50.1 92.0+81.1
,,R (%) 11.0*55.0 21.0*21.1 51.0*58.0
&: (%) 02.0*95.1 11.0*70.1 21.Oi27.0
124
Q-
’w
”o; ”08
d dd
x +! x-ii
“-3
d dd
422 .F Balestra et al. / Strangeness production
4.0
t
3.5
I-
3.0
2.5
%*R 2.0
t
1.5
-t
1.0
0.5
+
0.0 +
2.4
2.0 t
1.6
“q” 1.2
t
0.8
0.4
, ,
0.0 I I I , I ,
1.4
1.2
1.0
R 0.8
0.6
0.4
0.2
I * I * 1I II
H2 eH4 N4‘ iT84 ‘6’T,
H‘ eH3 ‘2C eNO2 ‘31X, 208Pb
.giF .2 noitubirtsiD fo ,,R :KR dna R rof tnereffid stnemirepxe no ’V+Ap X ta tser =’V( zK ro .)A
fig. 2 we show the noitubirtsid of ,AR R,; dna R for tnereffid stnemirepxe no +AP V”
X at rest (V” si iK or .)A
2.3.2. snoitalihinnA ni thgirf below 1600 MeV/c.
(a) R,(*H) dna R,$*H) esaercni htiw mutnemom ni hcus a yaw that R syats
tsomla .tnatsnoc
F. Balestra et al. / Strangeness production 423
)b( R,, sesaercni as a noitcnuf of A.
(c) R,, at 600 MeV/c si regral naht the gnidnopserroc eulav at rest.
(d) R(‘H) syats tnatsnoc htiw gnisaercni mutnemom dna si tuoba eno order of
edutingam rellams naht R(A 2 4).
2.3.3. Annihilation above 1600 MeV/c.
(a) evobA AX dlohserht R, (‘H) esaercni htiw ygrene elihw Rk$‘H) si ylriaf
.tnatsnoc tA 9 ,c/VeG R, (‘H) .)H‘$,Ri- A ralimis ruoivaheb si devresbo for
R,(*H) dna R,$*H).
)b( R,1(2H) dna )H2(i,R yrav ylhtooms hguorht the AA ,dlohserht yrartnoc ot
the noitautis for R,,, )aTI“( hcihw si tuoba eno order of edutingam regral at 4-3 c/VeG
naht at rest.
(c) R,, )aT’81( at 4-3 c/VeG si eno order of edutingam regral naht R, (‘H) dna
R,4(2H) at the emas .atnemom nO the other ,dnah R,g sdneped yletaredom of A.
emoS processes ni aT‘“ esaercni ylgnorts the A noitcudorp tuohtiw gnicuder the
zK .dleiy
(d) )H‘(;,R < Rk$‘H), dna siht si ton yltneiciffus decnalab yb )H‘(nR > R,,(‘H).
nI elbat 4 we tneserp the tnerruc latnemirepxe noitautis gninrecnoc the latot citsaleni
cross noitces niT( = totu - aa,. eW refni that niT( sevaheb as 3’2A )H‘(,iic rebmun( ni
)sisehtnerap revo a egral egnar of A dna of ?I .mutnemom morF elbat 5 we see that
a, dna ;ka etaived ylgnorts morf hcus a ruoivaheb ‘).
nI elbat 6 we tneserp a weiver of lacitamenik ,seititnauq charge seiticilpitlum dna
seiticilpitlum of evitagen tracks (Y dna )-K where we nac ekam the gniwollof
:snoitavresbo
- ehT egareva rebmun of charged selcitrap NC,, dna of evitagen selcitrap -,N are
rehgih for noitalihinna stneve ni lareneg lla( )sepyt naht for those htiw A dna/ro
.iK sihT stcelfer the fact that stneve htiw egnarts elcitrap noitcudorp evah ssel
ygrene elbaliava for noitcudorp of r*.
TABLE 4
latoT citsaleni ssorc snoitces ni p A .snoitcaer ehT eulav rof eN‘“ si -itserednu
detam yb %5= .fer[ .])93 srebmuN ni sesehtnerap morf nit = A213 o,“(‘H)
006 MeV/ c 0003 c/VeM 0004 MeV/ c
H‘ 7.49 f 4.2 ‘*) 1*35 )13 *4.05 )132.1
H2 1.3k8.261 )43 )’3311=
eH4 932 * 5 *‘)
)6*832(
*‘Ne 12+326 )93
+896( )81
aT‘*‘ )6303*6561 )”03*8261
)23*6961( )83*3161(
424 .F Balestra et al. / Strangeness production
TABLE 5
ssorC snoitces fo A dna zK ni p A snoitalihinna
600 MeV/ c 4 /VeG c
H* .fer[ I)“ eH4 .fer[ I)“ *‘Ne .fer[ I)“ H‘ .fer[ I)“ aT‘“ .fer[ ])’I
,,a )bb 41.0*56.0 76.3 * 65.0 3.21 8.2k 35.0 * 50.0 21-k391
:KU )bm( 47.3 * 65.0 09.3 * 35.0 *4.5 1.1 09.1 f 70.0 6*28
- NC,, for stneve htiw A si rehgih naht for those htiw gK hcihw yam tcelfer that the
suelcun si erom ylgnorts .devlovni
- Note that we nac ylno state the rewol stimil of NC,, for p aT‘*‘ at 4 .c/VeG ehT
nosaer si that sgnorp htiw mutnemom ssel naht 100 MeV/c tonnac eb devresbo ni
that .tnemirepxe ecniS ni ruo tnemirepxe we are gnisu a gas target we are elba ot
detect hcus sgnorp dna we evah deedni etiuq a tol of meht 19,20).
.4.2 ATAD SISYLANA
eW llahs tsrif emussa that lla A are decudorp hguorht K ,gnirettacser ni the
processes
,-NP )rrm(KK ...2,1,0=m
dewollof yb
htiw a niatrec ytilibaborp PK,,, of K gnitrevnoc ot A ni the .suelcun gnimussA a
PK~ rate as nevig evoba we nac etaluclac PK+,, as
PK+* = (R/l )exp/Pi& *
PiCell si na etamitse of the egareva eulav of the seitilibaborp Pco_~ dna P,-+, that
”K or -K trevnoc ot a A ni the .suelcun fI PC+,, si nwonk we nac etamitse R desab
no the gniwollof :snoitpmussa
- ehT noitcudorp of ,KK together htiw yna rebmun of ,snoip has a ytilibaborp PcK
of tuoba %7-5 htiw respect ot the latot rebmun of stneve ni NN snoitalihinna at
rest ‘). nI ref. 21) a eulav of PK~ = 3% si dnuof ni suelcun-notorpitna .snoitalihinna
eW therefore emussa the PkK rate ot eb 3% (or ylevitanretla 5%) at rest.
eW etaluclac R = ( Rn)exp/RKg for htob these two .sevitanretla sA ni ref. )“ we
emussa PK~ ot esaercni ylraenil as a noitcnuf of the notorpitna ,mutnemom .e.i at
607 MeV/c we tup PK~ = 4.5 (6.5)%.