Myrianthopoulos, L.C.
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Single Spin Asymmetry $A_N$ in Polarized Proton-Proton Elastic Scattering at $\sqrt{s}=200$ GeV

The STAR collaboration Adamczyk, L. ; Agakishiev, G. ; Aggarwal, M.M. ; et al.
Phys.Lett.B 719 (2013) 62-69, 2013.
Inspire Record 1117881 DOI 10.17182/hepdata.102952

We report a high precision measurement of the transverse single spin asymmetry $A_N$ at the center of mass energy $\sqrt{s}=200$ GeV in elastic proton-proton scattering by the STAR experiment at RHIC. The $A_N$ was measured in the four-momentum transfer squared $t$ range $0.003 \leqslant |t| \leqslant 0.035$ $\GeVcSq$, the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of $A_N$ and its $t$-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the single spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated by the Pomeron amplitude at this $\sqrt{s}$, we conclude that this measurement addresses the question about the presence of a hadronic spin flip due to the Pomeron exchange in polarized proton-proton elastic scattering.

3 data tables
Table 3

The asymmetry $\varepsilon(\varphi)/(P_B + P_Y)$ for various $t$-intervals.

Table 4

The measured single spin asymmetry $A_N$ for five $-t$ intervals.

Table 5

Fitted value of $r_5$.


Neutron - proton elastic scattering spin - spin correlation parameter. Measurements between 500 and 800 - MeV. 3. Mixtures of C(ss), C(ls), C(ll), and C(nn).

Carlson, V. ; Garnett, R. ; Hill, D. ; et al.
Phys.Rev.D 53 (1996) 3506-3533, 1996.
Inspire Record 404963 DOI 10.17182/hepdata.50927

Measurements are presented for several mixtures of the spin observables CSS,CSL=CLS, CLL, and CNN for neutron-proton elastic scattering. These data were obtained with a free polarized neutron beam, a polarized proton target, and a large magnetic spectrometer for the outgoing proton. The neutron beam kinetic energies were 484, 567, 634, 720, and 788 MeV. Combining these results with earlier measurements allows the determination of the pure spin observables CSS, CLS, and CLL at 484, 634, and 788 MeV for c.m. angles 25°≤θc.m.≤180° and at 720 MeV for 35°≤θc.m.≤80°. These data make a significant contribution to the knowledge of the isospin-0 nucleon-nucleon scattering amplitudes. © 1996 The American Physical Society.

19 data tables
Table 1

Results for the pure spin observables. Statistical errors only. (Data for CSS and CNN at (172.5 to 177.5) and (167.5 to 172.5) degrees are uncertain because of the rapid angular dependence and possible errors in angle, and may be omitted from phase shift analyses.) The CNN data without errors are from a phase shift analysis of Arndt et al. (PR D45 (1992) 3395) [FA92] and were used to derive pure spin observables from the measured data.

Table 2

Results for the pure spin observables. Statistical errors only. (Data for CSS and CNN at (172.5 to 177.5) and (167.5 to 172.5) degrees are uncertain because of the rapid angular dependence and possible errors in angle, and may be omitted from phase shift analyses.) The CNN data without errors are from a phase shift analysis of Arndt et al. (PR D45 (1992) 3395) [FA92] and were used to derive pure spin observables from the measured data.

Table 3

Results for the pure spin observables. Statistical errors only. The CNN data without errors are from a phase shift analysis of Arndt et al. (PR D45 (1992) 3395) [FA92] and were used to derive pure spin observables from the measured data.

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Neutron - proton elastic scattering spin spin correlation parameter measurements between 500-MeV and 800-MeV. 2. C(SS) and C(LS) at forward cm angles

Shima, T. ; Hill, D. ; Johnson, K.F. ; et al.
Phys.Rev.D 47 (1993) 29-45, 1993.
Inspire Record 335383 DOI 10.17182/hepdata.22585

Results are presented for the spin-spin correlation parameters CSS and CLS for free np elastic scattering at neutron beam kinetic energies of 484, 634, 720, and 788 MeV and c.m. angles between 25° and 80°. The measurements were performed with a polarized neutron beam and a polarized proton target. These are the first measurements of this type to be reported in the forward angular region with a free polarized neutron beam. The observables CSS and CLS are both small at all energies, except for CLS at 788 MeV, which is larger than phase-shift analysis predictions by more than one standard deviation for most of the measured points.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Neutron proton elastic scattering spin spin correlation parameter measurements between 500-MeV and 800-Mev: 1. C(SL) and C(LL) at backward c.m. angles

Ditzler, W.R. ; Hill, D. ; Hoftiezer, J. ; et al.
Phys.Rev.D 46 (1992) 2792-2830, 1992.
Inspire Record 334079 DOI 10.17182/hepdata.22741

Final results are presented for the spin-spin correlation parameters CSL and CLL for np elastic scattering with a polarized neutron beam incident on a polarized proton target. The beam kinetic energies are 484, 634, and 788 MeV, and the c.m. angular range is 80°-180°. These data will contribute significantly to the determination of the isospin-0 amplitudes in the energy range from 500 to 800 MeV.

6 data tables
Table 1

Pure np elastic scattering spin variables. CLL and CSL derived from measured combined spin variable. Thus the errors on CLL and CSL are slightly correlated. There are also additional systematic errors of 7 pct associated with beam and 3.3 pct target polarizations respectively.

Table 2

Pure np elastic scattering spin variables. CLL and CSL derived from measured combined spin variable. Thus the errors on CLL and CSL are slightly correlated. There are also additional systematic errors of 7 pct associated with beam and 3.3 pct target polarizations respectively.

Table 3

Pure np elastic scattering spin variables. CLL and CSL derived from measured combined spin variable. Thus the errors on CLL and CSL are slightly correlated. There are also additional systematic errors of 7 pct associated with beam and 3.3 pct target polarizations respectively.

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n p elastic spin transfer measurements at 485-MeV and 635-MeV

McNaughton, K.H. ; Ambrose, D.A. ; Coffey, P. ; et al.
Phys.Rev.C 46 (1992) 47-51, 1992.
Inspire Record 342389 DOI 10.17182/hepdata.26097

We have measured the spin-transfer parameters KLL, KSL, KLS, and KSS at 635 MeV from 50° to 178° c.m. and at 485 MeV from 74° to 176° c.m. These new data have a significant impact on the phase-shift analyses. There are now sufficient data near these energies to overdetermine the elastic nucleon-nucleon amplitudes.

2 data tables
Table 1

Spin transfer parameters from np elastic scattering at 635 MeV. There is an additional overall normalisation of 2 PCT.

Table 2

Spin transfer parameters from np elastic scattering at 485 MeV. There is an additional overall normalisation of 2 PCT.


Energy dependent measurements of the p p elastic analyzing power and narrow dibaryon resonances

Kobayashi, Y. ; Kobayashi, K. ; Nakagawa, T. ; et al.
Nucl.Phys.A 569 (1994) 791-820, 1994.
Inspire Record 320015 DOI 10.17182/hepdata.38528

The energy dependence of the pp elastic analyzing power has been measured using an internal target during polarized beam acceleration. The data were obtained in incident-energy steps varying from 4 to 17 MeV over an energy range from 0.5 to 2.0 GeV. The statistical uncertainty of the analyzing power is typically less than 0.01. A narrow structure is observed around 2.17 GeV in the two-proton invariant mass distribution. A possible explanation for the structure with narrow resonances is discussed.

1 data table
Table 1

Statistical errors only.


Measurement of a Mixed Spin Spin Correlation Parameter for $n p$ Elastic Scattering

Garnett, R. ; Rawool, M. ; Carlson, V. ; et al.
Phys.Rev.D 40 (1989) 1708, 1989.
Inspire Record 25430 DOI 10.17182/hepdata.23054

The mixed spin-spin correlation parameter Cσσ≈0.5CSS−0.8CSL for np elastic scattering was measured for incident-neutron-beam kinetic energies of 484, 634, and 788 MeV over the center-of-mass angular range 75°-180°. These Cσσ data are important for determining the I=0 nucleon-nucleon amplitudes and provide strong constraints on the phase-shift solutions. It was found that the P11, S13, and D13 isospin-0 partial waves are most strongly affected.

3 data tables
Table 1

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.475 * CSS + 0.088 CNN + 0.1390 CLL - 0.744 CSL.

Table 2

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.506 * CSS + 0.064 CNN + 0.163 CLL - 0.809 CSL.

Table 3

Mixed spin parameter POL.POL(NAME=CXX) is given by 0.528 * CSS + 0.050 CNN + 0.178 CLL - 0.824 CSL.


Spin Correlation Parameter A(nn) ($\theta^*$) for $n p$ Elastic Scattering at 790-{MeV}

Nath, S. ; Glass, G. ; Hiebert, J.C. ; et al.
Phys.Rev.D 39 (1989) 3520, 1989.
Inspire Record 25429 DOI 10.17182/hepdata.23226

The spin-correlation parameter Ann for free n-p elastic scattering has been measured for the first time for incident-neutron-beam energy En=790 MeV and c.m. angles 48°≤θ*≤149°. The data are compared with the widely differing predictions of several phase-shift analyses, clearly favoring one of them. They also are compared with recently published quasifree Ann data for the more limited c.m. angular region 98°≲θ*≲122°.

1 data table
Table 1

No description provided.


The Acceleration of Polarized Protons to 22-{GeV}/$c$ and the Measurement of Spin Spin Effects in $p$ (Polarized) + $p$ (Polarized) $\to p + p$

Khiari, F.Z. ; Cameron, P.R. ; Court, G.R. ; et al.
Phys.Rev.D 39 (1989) 45, 1989.
Inspire Record 262472 DOI 10.17182/hepdata.23245

Accelerating polarized protons to 22 GeV/c at the Brookhaven Alternating Gradient Synchro- tron required both extensive hardware modifications and a difficult commissioning process. We had to overcome 45 strong depolarizing resonances to maintain polarization up to 22 GeV/c in this strong-focusing synchrotron. At 18.5 GeV/c we measured the analyzing power A and the spin-spin correlation parameter Ann in large- P⊥2 proton-proton elastic scattering, using the polarized proton beam and a polarized proton target. We also obtained a high-precision measurement of A at P⊥2=0.3 (GeV/c)2 at 13.3 GeV/c. At 18.5 GeV/c we found that Ann=(-2±16)% at P⊥2=4.7 (GeV/c)2, where it was about 60% near 12 GeV at the Argonne Zero Gradient Synchrotron. This sharp change suggests that spin-spin forces may have a strong and unexpected energy dependence at high P⊥2.

3 data tables
Table 1

No description provided.

Table 2

2.2 GeV point taken from Brown et al., PR D31(85) 3017.

Table 3

No description provided.


Measurement of C(ll) and C(sl) in $N P$ Elastic Scattering at 484-{MeV} and 634-{MeV}

Burleson, G.R. ; Faucett, J.A. ; Fontenla, C.A. ; et al.
Phys.Rev.Lett. 59 (1987) 1645, 1987.
Inspire Record 21907 DOI 10.17182/hepdata.3247

The spin-spin correlation parameters CLL=(L,L;0,0)=ALL and CSL=(S,L;0,0)=ASL for np elastic scattering were measured for incident polarized-neutron–beam kinetic energies of 484 and 634 MeV over the center-of-mass angles from ≃80° to 180°. The data are important for determining the I=0 nucleon-nucleon amplitudes. These results are compared with phase-shift calculations.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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