摘要:

I summarize the physics issues that are important for a polarized hadron–hadron collider.

ISSN:0094-243X    

DOI:10.1063/1.40480

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The results of experiment with Siberian Snakes are presented. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.40473

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

In low to medium energy accelerators, betatron tune jumps and vertical orbit harmonic correction methods have been used to overcome the intrinsic and imperfection resonances. At high energy accelerators, snakes are needed to preserve polarization. We analyze the effects of snake resonances, snake imperfections overlapping resonances on the spin depolarization. We discuss also results of recent snake experiments at the IUCF Cooler Ring. The snake can overcome various kinds of spin depolarization resonances. These experiments pointed out further that partial snake can be used to cure the imperfection resonances in low to medium energy accelerators. We also examine various snake designs. A new generalized snake concept allows for two possible configurations. The compact configuration offers the advantages of shorter total snake length and smaller horizontal orbit displacement. The split snake configuration allows for dual functions of a snake and a 90° spin rotator at the mid‐section of the snake, which provides helicity state collisions. The requirements for obtaining high luminosity polarized protons at high energy colliders, such as RHIC and SSC, are reviewed.

ISSN:0094-243X    

DOI:10.1063/1.40497

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

A brief review is given of our knowledge of the spin dependent structure functions of the nucleon and of some plans for future experiments.

ISSN:0094-243X    

DOI:10.1063/1.40508

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Assuming that future hadron machines will have polarized proton beams we show the relevance of spin effects for the next generation ofppcolliders and supercolliders. We calculate various helicity asymmetries in the multi‐TeV energy range and also below 1 TeV for a selection of processes in the appropriate kinematic regions. We will see that some of our results are spectacular and can help to pin down fundamental issues in the framework of the Standard Model.

ISSN:0094-243X    

DOI:10.1063/1.40509

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

We examine the role of quarks and gluons in polarized leptoproduction in connection with the famous EMC experimental result. The gluon contribution generated by the axial anomaly is shown to have a well defined physical meaning and its gauge invariance properties are fully clarified. We also emphasize the role of the ghost contribution in the generalized Goldberger‐Treiman relation.

ISSN:0094-243X    

DOI:10.1063/1.40510

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Implications of the EMC experiment and several other experiments for the strangeness content of the proton are presented. The gluon contribution to the proton spin is shown to be arbitrary due to factorisation ambiguities, so adding a gluon contribution cannot explain why &Dgr;smight be large. The polarized gluon distribution &Dgr;gis shown to be given by a gauge invariant but non‐local operator. Other topics discussed include the gauge variation of the forward matrix element ofK&mgr;, whether &Dgr;gcan be measured by studying large transverse momentum jets, the angular momentum sum rule, and the implications of the renormalisation group invariance of &Dgr;&Sgr;+(&agr;s/2&pgr;) &Dgr;gfor quark models. &Dgr;sin the proton is analysed using the chiral quark model, and in the largeNclimit.

ISSN:0094-243X    

DOI:10.1063/1.40511

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

This review of unpolarized parton distributions in the perturbative QCD framework examines contemporary issues on next‐to‐leading order studies, assesses the current status of global analysis of these distributions, and discusses the wide scope of physical processes relevant for improving the second‐generation analyses and for resolving the remaining open questions. Subtlies and pitfalls are delineated—with a view of extracting pertinent lessons for the emerging study of polarized parton distributions.

ISSN:0094-243X    

DOI:10.1063/1.40469

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

A polarized collider has been proposed as an polarization option of the ‘‘PS Collider’’ which is a future project of the Proton Synchrotron at KEK. A brief description on the current plan about the collider is given and the possible physics with this machine is discussed.

ISSN:0094-243X    

DOI:10.1063/1.40470

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized‐beam facility, measurements of beam polarization by polarimeters (Fermilab E‐581), asymmetry measurements in the &pgr;° production at high p⊥and in the &Lgr; (&sgr;°), &pgr;±, &pgr;° production at large xF, ad &Dgr;&sgr;L(pp, p¯p) mesurements (Fermilab E‐704). In future we plan to investigate the proton‐spin crisis by determining the gluon spin distribution in inclusive production of direct gamma, &khgr;2, and J/&psgr;.

ISSN:0094-243X    

DOI:10.1063/1.40471

出版商:AIP    

年代:1991

数据来源: AIP