Atwood, W.B
[2.0, 3.0]
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rivet Analysis
Measurement of the proton form factor by studying $e^{+} e^{-}\rightarrow p\bar{p}$

The BESIII collaboration Ablikim, M. ; Achasov, M.N. ; Ai, X.C. ; et al.
Phys.Rev.D 91 (2015) 112004, 2015.
Inspire Record 1358937 DOI 10.17182/hepdata.73442

Using data samples collected with the BESIII detector at the BEPCII collider, we measure the Born cross section of $e^{+}e^{-}\rightarrow p\bar{p}$ at 12 center-of-mass energies from 2232.4 to 3671.0 MeV. The corresponding effective electromagnetic form factor of the proton is deduced under the assumption that the electric and magnetic form factors are equal $(|G_{E}|= |G_{M}|)$. In addition, the ratio of electric to magnetic form factors, $|G_{E}/G_{M}|$, and $|G_{M}|$ are extracted by fitting the polar angle distribution of the proton for the data samples with larger statistics, namely at $\sqrt{s}=$ 2232.4 and 2400.0 MeV and a combined sample at $\sqrt{s}$ = 3050.0, 3060.0 and 3080.0 MeV, respectively. The measured cross sections are in agreement with recent results from BaBar, improving the overall uncertainty by about 30\%. The $|G_{E}/G_{M}|$ ratios are close to unity and consistent with BaBar results in the same $q^{2}$ region, which indicates the data are consistent with the assumption that $|G_{E}|=|G_{M}|$ within uncertainties.

1 data table
Table 1

Summary of the Born cross section $\sigma_\text{Born}$, the effective FF $|G|$, and the related variables used to calculate the Born cross sections at the different c.m.energies $\sqrt{s}$, where $N_\text{obs}$ is the number of candidate events, $N_\text{bkg}$ is the estimated background yield, $\varepsilon^\prime=\varepsilon\times(1+\delta)$ is the product of detection efficiency $\varepsilon$ and the radiative correction factor $(1+\delta)$, and $L$ is the integrated luminosity. The first errors are statistical, and the second systematic.


rivet Analysis
Measurement of inclusive monmentum spectra and multiplicity distributions of charged particles at s**(1/2) approx. 2-GeV to 5-GeV.

The BES collaboration Dunwoodie, W. ; Bai, J.Z. ; Ban, Y. ; et al.
Phys.Rev.D 69 (2004) 072002, 2004.
Inspire Record 622224 DOI 10.17182/hepdata.22183

Inclusive momentum spectra and multiplicity distributions of charged particles measured with BESII detector at center of mass energies of 2.2,2.6,3.0,3.2,4.6 and 4.8 GeV are presented. Values of the second binomial moment, $R_2$, obtained from the multiplicity distributions are reported. These results are compared with both experimental data from high energy $e^+e^-$, $ep$ and $p\bar{p}$ experiments and QCD calculations.

12 data tables
Table 1

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 2.2 GeV.. Errors are statistical and systematic added in quadrature.

Table 2

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 2.6 GeV.. Errors are statistical and systematic added in quadrature.

Table 3

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 3.0 GeV.. Errors are statistical and systematic added in quadrature.

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rivet Analysis
Measurements of the Cross Section for e+e- -> hadrons at Center-of-Mass Energies from 2 to 5 GeV

The BES collaboration Bai, J.Z. ; Ban, Y. ; Bian, J.G. ; et al.
Phys.Rev.Lett. 88 (2002) 101802, 2002.
Inspire Record 552757 DOI 10.17182/hepdata.41990

We report values of $R = \sigma(e^+e^-\to {hadrons})/\sigma(e^+e^-\to\mu^+\mu^-)$ for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

1 data table
Table 1

Measured values of R.


Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Barlow, D.B. ; Saha, A. ; Seth, K.K. ; et al.
Phys.Rev.C 37 (1988) 1977-1986, 1988.
Inspire Record 242361 DOI 10.17182/hepdata.26282

Angular distributions of the spin-correlation parameters Asl and All for the reaction pp→π+d have been measured at pion center-of-mass angles 40°≤θπ+*≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of All were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Charged Meson Pair Production in $\gamma \gamma$ Interactions

Boyer, J. ; Burke, D.L. ; Butler, F. ; et al.
Phys.Rev.Lett. 56 (1986) 207, 1986.
Inspire Record 220003 DOI 10.17182/hepdata.20236

The cross section for the production of π+π− or K+K− pairs in γγ interactions is measured for mππ between 1.7 and 3.5 GeV/c2 and for two intervals of γγ center-of-mass scattering angle. Results are compared with predictions of a QCD model.

2 data tables
Table 1

Data read off graph.

Table 2

Data read off graph.


MEASUREMENTS OF SPIN CORRELATION PARAMETER A(NN) AND ANALYZING POWER AT 90-degrees FOR P (polarized) P (polarized) ---> D PI+ BETWEEN 500-MEV AND 800-MEV

Glass, G. ; Bhatia, T.S. ; Hiebert, J.C. ; et al.
Phys.Rev.Lett. 53 (1984) 1984-1987, 1984.
Inspire Record 214991 DOI 10.17182/hepdata.20423

Measurements of the spin observables ANN(90∘) and AN0(90∘) for the reaction pp→dπ+ between 500 and 800 MeV are presented and compared with previous measurements and with predictions from theories and a partial-wave analysis. These are the first available measurements of ANN above 590 MeV.

1 data table
Table 1

ANALYSING POWER IS POL.POL(NAME=AN0).


MEASUREMENT OF DELTA SIGMA-l AND C (L, L) = (L, L : 0, 0) N PROTON PROTON SCATTERING BETWEEN 300-MEV AND 800-MEV

Auer, I.P. ; Ditzler, W.R. ; Hill, D. ; et al.
Phys.Rev.D 29 (1984) 2435-2468, 1984.
Inspire Record 205458 DOI 10.17182/hepdata.23728

Measurements are reported of the difference ΔσL between proton-proton total cross sections for parallel and antiparallel spin states and of the parameter CLL for proton-proton elastic scattering near 90°, for thirteen energies between 300 and 800 MeV. The ΔσL results agree well with previous ANL ZGS and SIN data, but disagree with recent results from TRIUMF. Attempts to understand the cause of the discrepancy have been unsuccessful, but possible sources are discussed. The ΔσL and CLL results have been used with other experimental data to extract quantities which depend only on spin-singlet, coupled spin-triplet, and spin-triplet partial waves. Structure is found in these quantities, which appears to be associated with the resonantlike D21 and F33 partial waves. Additional similar structure is also found, which may be due either to the P03 partial wave or the (P23,F23) partial-wave pair.

3 data tables
Table 1

ERROR IS STATISTICAL ONLY (ERROR IN BRACKETS IS STATISTICAL WITH THE ENERGY DEPENDENT UNCERTAINTIES FOLDED IN).

Table 2

ERRORS ARE STATISTICAL ONLY. THERE IS ADDITION OF 2.0 AND 2.1 PCT SYSTEMATICS.

Table 3

No description provided.


Measurements of the Spin Spin Correlation Parameter C(ss) = (S,s:o,o) at 487-{MeV}, 639-{MeV} and 791-{MeV}

Ditzler, W.R. ; Hill, D. ; Imai, K. ; et al.
Phys.Rev.D 29 (1984) 2137, 1984.
Inspire Record 201499 DOI 10.17182/hepdata.23771

The spin-spin correlation parameter CSS=(S,S;0,0) has been measured for p−p elastic scattering over a large angular range. The data are particularly useful in checking currently available phase-shift solutions.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


MEASUREMENT OF THE DIFFERENCE IN P P TOTAL CROSS-SECTIONS FOR PURE PARALLEL AND ANTIPARALLEL TRANSVERSE SPIN STATES (DELTA SIGMA (T AT T(P) = 487-MEV, 639-MEV, AND 791-MEV

Ditzler, W.r. ; Hill, D. ; Imai, K. ; et al.
Phys.Rev.D 27 (1983) 680-683, 1983.
Inspire Record 192364 DOI 10.17182/hepdata.23817

The difference between total cross sections in pure transverse-initial-spin states for the p−p interaction has been measured at Tp=487, 639, and 791 MeV, using a frozen-spin target. A comparison with previous data and available phase-shift analyses is made.

1 data table
Table 1

No description provided.


C(LL) = (L, L: 0, 0) MEASUREMENTS AND A STRUCTURE DUE TO A P PARTIAL WAVE IN THE P P SYSTEM

Burleson, G.r. ; Cottingame, W.b. ; Greene, S.j. ; et al.
Nucl.Phys.B 213 (1983) 365-370, 1983.
Inspire Record 191085 DOI 10.17182/hepdata.34015

Measurements of C LL of pp elastic scattering near θ c.m. = 90° at thirteen energies between 300 and 800 MeV are reported. These, together with previous values of C NN , are used to extract values of two quantities, ƒ s and ƒ t , which contain only spin-singlet and only coupled spin-triplet partial waves, respectively. The ƒ s curve, which is not dependent on C LL , exhibits the behavior expected for the previously conjectured 1 D 2 resonance. The ƒ t curve also exhibits a resonance-like behavior, which could be due either to the 3 P 0 or the 3 P 2 partial wave.

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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