Hard Parton Physics in High-Energy Nuclear Collisions [RIKEN BNL Workshop proc]

288 Pages·1999·20.565 MB·English

BNL-52574
Formal Report
Proceedings of RIKEN BNL Research Center Workshop Volume 17
HARD PARTON PHYSICS IN HIGH-ENERGY
NUCLEAR COLLISIONS
hcraM ,5-l 1999
srezinagrO
Jim ,llorraC selrahC ,elaG ekiM Tannenbaum and Raju nalapoguneV
NEKIR LNB hcraeseR retneC
gnidliuB 510, Brookhaven lanoitaN Laboratory, Upton, YN 11973, USA
Other RIKEN BNL Research Center Proceedings Volumes:
emuloV 16 - NEKIR retniW loohcS - erutcurtS fo snordaH noitcudortnI- ot QCD Hard
-sessecorP -LNB
emuloV 15 - QCD esahP snoitisnarT - 16525-LNB
emuloV 14 - mutnauQ sdleiF nI dna tuO fo muirbiliuqE - 06525-LNB
emuloV 13 - scisyhP fo eht 1 polfareT aibmuloC-LNB-NEKIR QCD tcejorP
tsriF yrasrevinnA noitarbeleC - 99266-LNB
emuloV 12 - muinokrauQ noitcudorP ni citsivitaleR raelcuN snoisilloC - 95525-LNB
emuloV 11 - tnevE rotareneG rof CIHR nipS scisyhP - 61166-LNB
emuloV 10 - scisyhP fo yr,temiraloP at CIHR - 62956-LNB
emuloV 9 - hgiH ytisneD rettaM ni ,SGA SPS dna CIHR snoisilloC - 26756-LNB
emuloV 8 - noimreF sreitnorF ni rotceV ecittaL eguaG seiroehT - 43656-LNB
emuloV 7 - CIHR nipS scisyhP - 51656-LNB
emuloV 6 - skrauQ dna snoulG ni eht noelcuN - 43256-LNB
emuloV 5 - roloC ,ytivitcudnocrepuS snotnatsnI dna ytiraP noitavresnoC-)?noN( at
hgiH noyraB ytisneD - 50156-LNB
emuloV 4 - noitaruguanI ,ynomereC rebmetpeS 22 dna
muirbiliuqE-noN ynaM ydoB scimanyD - -LYNB 64912
emuloV 3 - nordaH pilF-nipS at CIHRI seigrenE - 42746-LNB
emuloV 2 - evitabrutreP QCD as a eborP fo norlcaH erutcurtS - 32746-LNB
emuloV 1 - nepO sdradnatS rof edacsaC sledoM rof CIHR - 22746-LNB
Preface to the Series
ehT NEKIR LNB hcraeseR retneC saw dehsilbatse siht lirpA at nevabkoorB lanoitaN -obaL
.yrotar tI si dednuf yb eht ukagakiR“ ”ohsykneK etutitsnI( fo lacisyhP dna lacimehC )hcraeseR
fo .napaJ ehT retneC si detacided ot eht yduts fo gnorts ,snoitcaretni gnidulcni drah nips/DCQ
,scisyhp ecittal QCD dna CIHR scisyhp hguorht gnirutrun fo a wen noitareneg fo gnuoy .stsicisyhp
roF eht tsrif ,raey eht retneC lliw evah ylno a yroehT ,puorG htiw na latnemirepxE puorG ot
eb derutcurts .retal ehT yroehT puorG lliw tsisnoc fo tuoba 12- 15 scodtsoP dna ,swolleF dna snalp
ot evah na evitca gnitisiV tsitneicS .margor:p A polfaret lellarap rossecorp lliw eb detelpmoc at
0.6
eht retneC yb eht dne fo siht .raey nI ,noitidda eht retaeC sezinagro spohskrow deretnec no cificeps
smelborp ni gnorts .snoitcaretni
hcaE pohskrow rekaeps si degaruocne ot tceles a wef fo eht tsom tnatropmi seicnerapsnart
morf sih ro reh ,noitatneserp deinapmocca yb a egap fo .noitanalpxe sihT lairetam si detcelloc at
eht dne fo eht pohskrow yb eht rezinagro ot mrof a ,sgnideecor:p hcihw nac erofereht eb elbaliava
nihtiw a trohs .emit
.D.T eeL
yluJ 4, 1997
-kWork performed under the auspices of U.S.iI.0.E. Contract no. DE-ACO2-98CH10886.
i
CONTENTS
Preface to the Series
. . . . . . . . . . . . . . . . . . . . . . , . . * . . . . . . . . . . . . . . . i
Introduction
J. Carroll, C. Gale, M. muabnennaT dna R. Venugopalan . . . . . . . . . . , 1
Overview of Hard snotraP rof CIHR
G. Sterman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
muideM-nI ygrenE ssoL dna Jet scitsiretcarahc ni raelcuN -illoC
snois
I.P. Lokhtin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
erehW si eht ygrenE ?ssoL
X.-N. Wang . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
thgiL enoC msilamroF rof gnulhrtssmerB ni elpitluM gnirettacS
B. Kopeliovich . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . 22
yhW gnidaeL selcitraP naC eB desU ot erusaeM gnirettacS-draH at CIHR
.M J. Tannenbaum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Jets at AREH
M.W.Krasny . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Jets at eht nortaveT
J.Blazey . . . . . . . . . ~ . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Hard notraP scisyhP at eht nortaveT + stluseR morf 00
K. Turner . . . . . . . . . , . . . . . . . . . . . . . . . , . , . . . . . . . 47
snotraP ni A + A snoisilloC a,t CIHR htiw XINEHP
P. Stankus . . . . . . . . . . . . , . . . . . . . . . . . . . , . . . . . . . 52
ralugnA snoitalerroC at tp-hgiH
.C eivligO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Data steS rof hgiH tp scisyhP htiw eht RATS rotceteD
W.B. Christie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
noulG tejiniM noitcudorP ni hgiH ygrenE raelcuN snoisilloC
X ouG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
esrevsnarT mutnemoM ecnednepeD fo eht ladgiM-k.uhcnaremoP-uadnaL tceffE
U.A. Wiedemann . . . . . . . . . . . . . . . . . . . . . . . . . . , . 75
stluseR no tejiniM incitcudorP ni nordaH dna raelcuN snoisilloC
New
A. Leonidov . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
gniydutS notraP noitagaporP scimanyD ni :.1FATS hgiH s‘”r7fp ni Year-l
T.M. Cormier . . . . . . . ,. . . . . . . . . . . . . . . . . . . . . . . . 88
cinotraP erutciP fo raelcuN gniwodahS at llamS *x
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
I. Sarcevic
notpeliD noitcudorP at balimreF dna CIHR
J.C.Peng . . . . . . . . . . . . . . . . , , . . . . . . . . . . . . . . . . . . 98
deziralopnU dna deziraloP notraP snoitubirtsiD ni ielcuN
.S Kumano . . . . . . . . . . . . . . . . I . . . . . . . . . . . . . . . . . . 103
tp-hgiH tceriD notohP dna 7r” noitcudorP morf E706
109
M.Begel.....................................
A lacitirC lacigolonemonehP ydutS fo evisulcnI y‘ noitcudorP
P. Aurenche . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Hard notohP & noiP noitcudorP at CIHR seigrenE
P.Levai . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
noiP dna tceriD notohP noitcudorP ni raelcuN snoisilloC
T.Awes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
scisyhP htiw eht RATS HCIR
G.J. Kunde . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . 132
noulG gniwodahS dna detaleR QCD anemonehP
L. Frankfurt . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . 139
raelcuN gniwodahS fo noulG noitubirtsiD noitcnuF at CIHR dna CHL
146
J. Jalilian-Marian . . . . . ,, . . . . . . . . . . . . . . . . . . . . . . . . .
Hard gnirettacS ni deziraloP snoisilloC at ClHR
pp
W. Vogelsang . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
snotohP ni deziraloP noisilloC at XINEHP
pp
Y. 158
Goto . . . . . . . . . . . . ..I.....................
A tceriD noitcartxE fo GA htiw RATS
163
J. Sowinski _ , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ydutS fo rovalf-nipS erutcurtS fo eht noelcuN h,::iw XINEHP
169
N.Saito . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
noitaziraloP seidutS htiw ni RATS
W’s
175
A. Ogawa . . . . . . . , . . . , . . . . . . . . , . . . . . . . . . . . . .
gnitagitsevnI eht snigirO fo esrevsnarT nipS seirtemmysA at CIHR
181
D.Boer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ygrenE ssoL ni nihT samsalP
.lA Gyulassy . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . 187
snoulG at woL x
A. Kovner . . . . . . . . ,. . . . . . . . . . . . . . , . . . . . . . . . 193
gnirettacS fo owT kcohS sevaW dna ygrenE-hgiH evitceffE noitcA
I. Balitsky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
:J-llamS eru,tcurtS noitcnuF fo a suelcuN gnidulcnI elpitluM noremoP
F2
segnahcxE
Y. Kovclqov . . . . . . . . . . . . . . . . . 204
stceffE fo gniwodahS no laitinI snoitidnoC dna Hard seborP ni raelcuN
snoisilloC
R.Vogt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
llamS 2, Hard snoisillocbuS dna tfoS-draH ecafretnI
G. nosfatsuG . . . . . . . . . . . . . . . ,, . . . . . . . . . . . . . . . . . . 216
HIJING etnoM olraC
X.N. Wang . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
:INV noitalumiS fo ygrenE-hgiH elcitraP snoisilloC ni QCD
R. Longacre . . . . . . . . . . . . . . # . . . . . . . . . . . . . . . . . . . . 226
yalpretnI neewteB Hard dna tfoS scisyhP ni AA snoisilloC at CIHR
H.Sorge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
A worB-woL kooL at eht ytilartneC ecnednepeD fo Hard gnirettacS setaR
dna gnihcneuQ ni A-A dna p-A snoisilloC
B.A. Cole . . . . . . . . . . . . . . . . . , . , . . . . . . . . . . . . . . . . 240
neddiH dna nepO mrahC at CIHR
D. Kharzeev . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
gnidnatsrednU labolG serutaeF - 1
S.Jeon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
yrammuS - sevitcepsreP Hard snotraP @ CIHR
L. McLerran . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
tsiL fo stnapicitraP
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
pohskroW adnegA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Introduction
ehT LNB-NEKIR retnec pohskr:ow no “Hard notrap scisyhp ni hgih ygrene raelcun
”snoisilloc saw dleh at LNB morf hcraM !ht5-tsl 1999. ehT sucof fo eht pohskrow saw no
drah seborp fo suelcun-suelcun snoisilloc taht lliw eb derusaem at CIHR htiw eht XINEHP
dna RATS .srotceted erehT erew tuoba 45 srekaeps dna revo 70 deretsiger stnapicitrap at
eht ,pohskrow htiw ylhguor a retrauq fo eht srekaeps morf .saesrevo
tuobA 60% fo eht sklat erew yroeht .sklat A. ecin weivrevo fo yroeht rof CIHR saw
dedivorp yb egroeG .namretS ehT laciteroeht sklat erew no a ediw egnar fo scipot ni QCD
hcihw nac eb deifissalc rednu eht :gniwollof
a) ygrene ssol dna eht ladgiM-kuhcnaremoP-uadnaL ,tceffe
b) tejinim n:oitcudorp dna ,noitarbiliuqe
)c llams x scisyhp dna laitini ,snoitidnoc
)d raelcun notrap snoitubirtsid dna ,gniwodahs
)e nips ,scisyhp
)f ,notohp ,notpel-id dna mrahc ,noitcudorp
)g ,noitazinordah dna snoitalumis ’fo hgih tp scisyhp ni tneve -areneg
.srot
lareveS fo eht latnemirepxe sklat dessucsid eht seitilibapac fo eht XINEHP dna RATS
srotceted at CIHR ni gnirusaem hgih tp selcitrap ni yvaeh noi .snoisilloc nI ,lareneg eseht
sklat erew dedulcni ni eht tnaveler yroeht .siioisses A noisses saw tes edisa ot ssucsid eht
nips margorp at CIHR htiw deziralop notorp .smaeb nI ,noitidda ereht erew srekaeps
morf 08, ,AREH eht dexif tegrat stnemirepxe at ,balimreF dna eht NREC dexif tegrat
bP+bP ,margorp ohw dedivorp lanoitidda evitcepsrep no a egnar fo seussi fo ecnaveler ot
;CIHR morf stej at eht ,nortaveT otl noitarutas fo notrap snoitubirtsid at ,AREH dna tnecer
gnilzzup atad no tcerid notohp noitcudorp ni dexif tegrat ,stnemirepxe gnoma .srehto
ehT htdaerb dna htped fo eht scipot ,dessucsid as llew as eht esolc noitcaretni neewteb
tnemirepxe dna ,yroeht edam rof a yrev gnitalumits .erehpsomta ehT aedi rof hcus a
pohskrow detanigiro htiw sualK ,regieG-redniK ohw dessap yawa yllacigart ni eht hsarc
fo riassiwS .tlF 111. s’sualK aedi saw ot evah lauqe srebmun fo elcitrap dna raelcun
,stsicisyhp stsiroeht dna ,stsilatnelmirepxe teg rehtegot dna hsarht tuo eht suoirav QCD
seussi tnaveler ot .CIHR tI s,aw a yrev citsilaedi ,noisiv dna ni ecitcarp ti yam evah
dekrow tuo tahwemos yltnereffid morf tahw eh dah .dennalp ,sselehtreveN ew eveileb
eht erehpsomta fo eht pohskrow saw eno eh dlrlow evah ,deyojne dna decnahne htiw sih
ylevil .tirips ehT pohskrow dna eseht sgnideecorp are detacided ot eht yromem fo sualK
.regieG-redniK
miJ llorraC
selrahC elaG
ekiM muabnennaT
ujaR nalapoguneV
Overview of Hard Partons for RHIC
George Sterman
Institute for Theoretical Physics
State University of New Crk at Stony Brook
Stony Brook, NY 117&-3840, USA
Perturbative Quantum Chromodynamics (pQCD) is the appropriate tool to describe QCD
dynamics at short distances. It allows us to treat quantities that are dominated by short-
distance physics and are yet observable, directly or indirectly. Hard scattering at RHIC requires
a reevaluation of pQCD formalism., appropriate to propagation through a dense, potentially
hot, final-state medium. The basic pQCD obserl;ables are the total and jet cross section-
s in e+e- annihilation, S(Q) = C,,,,,%(Q/p) a,(,~,). A n even richer class of observables can
be expressed as factorized conwoZzl;!:ionso f short-distance quantities with long-distance, non-
perturbative matrix elements. Examples are hard-scattering cross sections in hadron-hadron,
including nucleus-nucleus scattering,
ii’
relevant to a large class of final states F, characterized by heavy masses (or high momentum
transfers) M, that will be observable at RHIC, including jet, high-pr hadron, heavy-quark.
weak vector boson and direct photon production. The sums are over parton types i and i’.
with convolutions usually over their fractional momenta. The factorization scale p separates
perturbative dynamics from the long-distance funct,ions 4, describing the distributions of par-
tons in hadrons or nuclei, and/or th!e fragmetation of partons into hadrons. DGLAP evolution
equations, of the form @$(p)/dp = P(Q,(,Q))@c$, f o 11o w from the independence of the physica.
cross section from ,u, assuming that h is large enough tha.t a,(,~) and &D/P are small. With
its polarization capability, RHIC will make possible the measurement of spin-dependent distri-
butions. Nuclear collisions will pron:lote corrections to (1) associated wit,h multiple scatterings.
which are generally small corrections for nucleons, t-o prominence.
Of special interest are final states characterized by a hierarchy of hard scales, such as for t,he
production of heavy quarks or of geometrically narrow, but energetic jets. Denoting the induced
ratios by T, corrections of the form (r:(p) ln” T can arise at each order: with n :L k 5 2n + 1.
depending on the dynamics. Resummation techniques typically allows us to organize, a.nd often
explicitly to sum, infinite series of s,uch logarithms. Resummation is intimately related to t.he
sa.me factorization properties that l.ead t,o Eq. (l), and, in a wider context,, to eSfct?.ve field
theonJ descriptions of QCD dynamics. nI evitceffe dleif theories, evolut,ion is mnnifcstecl in the
renormalization of comp0sit.e operators. often pat,h--ordered exponc-:llti;lls. that, act. as sources
of soft gluons, associated with fast-moving part,ons, Iiv, = P exp--.l!/ ,I;;” d:~~i’ l A(y,f?)].
Relativistic effects t,ranslat,e evitwbrutrep scilnanylc revo long tlista.nces. For pp collisions.
the evolution is bet,wcen the scattered partons and the surrounding vacuum. In pA collisions.
nuclear media nlodify lligh-energy final states. tyI)ically t:hrough rrlr,tl(>st c:hanges in singlcl--
part~icle spect.ra. or relat,ivc transverse nlomenta. lcraH snotrl;p irl t,l~(: AA c~ollisions of RHIC’
may be scnsit,ive probes of oi~rl~~e vollit.ioii of tlic procllicctl liot sJ31.(:1ri. ‘The c~omparisoii of liigli-
117.p llotorls anal lladrons. st liclics of ,jct, fl-agIrient;ltio!i. spcct~r;~; K:ll (!S coi-rcl;Lt,ioris eXl1 OffCl
iI.Iltl
iiiforiiiat~ion oil t,lic clist.ril)ut ion of onerg!~ iri tlic c3l,;mtlirig lLa(lroIli(. ‘I’llc cvolutioll 01‘
IIliltt ('I‘.
off-shell I);ut,olis t.lilotigh liot lliat.t,c:r \vill ;~lso ~(‘17’1: OI tseL c1l.t li;~~l~.c,iiiz;ltic~~I~)r oc(5s itsc>lf.
2