Download presentation
Presentation is loading. Please wait.
1
in the impact parameter represantation
ASI-2008 « SYMMETRY and SPIN » PRAHA -2008 Spin-flip amplitude in the impact parameter represantation Oleg V. Selyugin BLTPh,JINR
2
Structure of hadron elastic scattering amplitude
Introduction Structure of hadron elastic scattering amplitude Non-linear equations and saturation Basic properties of the unitarization schemes b-dependence of the phases Analysing power in different unitarization schemes Summary P. , B. Nicolescu, O.V. Selyugin
3
Total cross-section Understand the asymptotic behavior of stot
new (precise) data to constraint the fit: stot vs (ln s)g 1% error ~1mb
4
Predictions Model stot sel/stot r(t=0) B (t=0) COMPET 111 0.11 Marsel
103 0.28 0.12 19 Dubna 128 0.33 0.19 21. Pomer.(s+h) 150 0.29 0.24 21.4 Serpukhov 230 0.67
5
Pomerons stot(s)~ Landshoff 1984 – soft P a = 0.08
Regge theory stot(s)~ Landshoff 1984 – soft P a = 0.08 Simple pole – (s/s0)a Double pole – Ln (s/s0) Triple pole – Ln2(s/s0) +C 1976 BFKL (LO) - P -a2 = 0.4 a2 = 0.45 1988 HERA data (Landshoff ) – hard P 2005 – Kovner – 7 P -ai =
7
Regge limit for fixed t The crossing matrix factorized in the limit
the Regge-pole contributions to the helicity amplitudes in the s-chanel when exchanged Regge poles have natural parity
8
Impact parameter representation
9
Unitarity in impact parameter representation
S S+ = 1
10
Saturation bound
11
Non-linear equation (K-matrix)
12
Non-linear equation (eikonal)
13
Eikonal and K-matrix
14
Eikonal and K-matrix
15
Interpolating form of unitarization
16
Normalization and forms of unitarization
Low energies
17
Inelastic cross sections
eikonal U-matrix
18
Asymptotic features of unitarization schemes
Low energies High energies
19
Effect of antishadowing
S. Troshin (hep-ph/ v4 June 4 « Black Disk Limit is a direct consequence of the exponential unitarization with an extra assumption on the pure imaginary nature of the phase shift » Renormalized eikonal
20
2 TeV
21
14 TeV
22
Corresponding phases
23
Renormalization of the U-matrix - K-matrix
24
RHIC beams +internal targets º
fixed target mode Ö s ~ 14 GeV
25
Analysing power
27
Eikonal case
29
K-matrix U-matrix
30
A N - eikonal
31
A N - eikonal
32
A N – Born term
33
A N – K-matrix
34
A N – K-matrix
35
A N – UT-matrix
36
A N – UT-matrix
38
A N – UT-matrix (New fit of from
39
Summary Unitarization effects is very important for the description spin correlation parameters at RHIC Non-linear equations correspond to the different forms of the unitarization schemes. They can have the same asymptotic regime. An interpolating form of unitarization can reproduce both the eikonal and the K-matrix (extended U-matrix} unitarization
40
Summary The true form of the unitarization, which is still to be determined, can help to determine the form of the non-linear equation, which describes the non-perturbative processes at high energies.
41
END
42
The experiments on proton elastic scattering occupy
an important place in the research program at the LHC. It is very likely that BDL regime will be reached at LHC energies It will be reflected in the behavior of B(t) and r(t).
43
Double Spin Correlation parameter
44
The Elastic Process: Kinematics
scattered proton (polarized) proton beam RHIC beams + internal targets º fixed target mode Ö s ~ 14 GeV polarized proton target or Carbon target recoil proton or Carbon essentially 1 free parameter: momentum transfer t = (p3 – p1)2 = (p4 – p2)2 <0 + center of mass energy s = (p1 + p2)2 = (p3 – p4)2 + azimuthal angle j if polarized ! Þ elastic pp kinematics fully constrained by recoil proton only ! С П И Н 0 5 Alessandro Bravar
45
Complex eikonal and unitarity bound
46
Some AN measurements in the CNI region
pC Analyzing Power p = 21.7 GeV/c PRL89(02)052302 pp Analyzing Power p = 200 GeV/c PRD48(93)3026 no hadronic spin-flip with hadonic spin-flip AN(%) no hadronic spin-flip r5pC µ Fshad / Im F0had Re r5 = ± 0.058 Im r5 = ± 0.226 highly anti-correlated -t С П И Н 0 5 Alessandro Bravar
47
Spin correlation parameter - AN
ANbeam (t ) = ANtarget (t ) for elastic scattering only! Pbeam = Ptarget . eB / eT
48
Soft and hard Pomeron Donnachie-Landshoff model;
Schuler-Sjostrand model
49
Such form of U-matrix does not have the BDL regime
Predictions at LHC (14 TEV)
50
Corresponding phases
51
Radius of the saturation
Low s
53
momentum transfer t = (p3 – p1)2 = (p4 – p2)2 <0
+ center of mass energy s = (p1 + p2)2 = (p3 – p4)2 + azimuthal angle j if polarized ! Þ elastic pp kinematics fully constrained by recoil proton only
54
Soft and hard Pomeron Donnachie-Landshoff model;
Schuler-Sjostrand model Cudell-Lengyel-Martynov-Selyugin
56
Corresponding phases 2
57
Extended forms of the unitarization
Ter-Martirosyan-Kaidalov Giffon-Martynov-Predazzi eikonal U-matrix
58
Interpolating form of unitarization
59
Elastic scattering amplitude
60
Impact parameter representation and unitarization schemes
61
General form of Unitarization
Ter-Martirosyan, Kaidalov Desgrolard, Martynov Miettinen, Thomas eikonal K-matrix
64
Eikonal
65
Impact parameters dependence
The Froissart bound Factorization
66
Bound on the region of validity of the U-matrix phase
Corresponding phases Bound on the region of validity of the U-matrix phase
67
U-matrix
68
TANGH
69
Total cross sections at the LHC
70
The r parameter linked to stot via dispersion relations
sensitive to stot beyond the energy at which is measured predictions of stot beyond LHC energies Or, are dispersion relations still valid at LHC energies?
71
If all particles are the same the amplitude do not changes with
2 last combination don’t satisfied the cgarge invariants and change signe of time If all particles are the same the amplitude do not changes with Change з1бз2 on л1бл2 and P->K K->P So the 6 cobination also disappear.
72
Saturation of the Gluon dencity
73
Interpolating form of unitarization
74
Interpolating form of unitarization
75
A N – UT-matrix
76
Eikonal and renormalized U-matrix
77
The nuclear slope parameter b
t-region of 10-2 10-1 GeV2 The b parameter is sensitive to the exchange process Its measurement will allow to understand the QCD based models of hadronic interactions “Old” language : shrinkage of the forward peak b(s) 2 ’ log s ; where ’ is the slope of the Pomeron trajectory 0.25 GeV2 Not simple exponential - t-dependence of local slope Structure of small oscillations?
78
An-UfT AN UmTei
79
Non-linear equations U-matrix eikonal
Similar presentations
© 2025 SlidePlayer.com Inc.
All rights reserved.