Affolder, Anthony Allen
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Precision measurement of R = sigma-L / sigma-T on hydrogen, deuterium and beryllium targets in deep inelastic electron scattering

The E140X collaboration Tao, L.H. ; Andivahis, L. ; Anthony, P. ; et al.
Z.Phys.C 70 (1996) 387-390, 1996.
Inspire Record 394123 DOI 10.17182/hepdata.13724

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive electron scattering from nuclei at x approximately = 1

Arrington, J. ; Anthony, P. ; Arnold, R.G. ; et al.
Phys.Rev.C 53 (1996) 2248-2251, 1996.
Inspire Record 394586 DOI 10.17182/hepdata.25857

The inclusive A(e,e') cross section for $x \simeq 1$ was measured on $~2$H, C, Fe, and Au for momentum transfers $Q~2$ from 1-7 (GeV/c)$~2$. The scaling behavior of the data was examined in the region of transition from y-scaling to x-scaling. Throughout this transitional region, the data exhibit $\xi$-scaling, reminiscent of the Bloom-Gilman duality seen in free nucleon scattering.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


C-12 (gamma,p) B-11 cross-section from 80 to 157 MeV

Harty, P.D. ; McGeorge, J.C. ; MacGregor, I.J.D. ; et al.
Phys.Rev.C 51 (1995) 1982-1990, 1995.
Inspire Record 411139 DOI 10.17182/hepdata.25963

The C12(γ,p)11B differential cross section has been measured over proton angles ranging from 58° to 128°, using tagged photons of energy 80–157 MeV, for low-lying regions of residual excitation energy in B11. The data have been compared with four different types of calculation. It is shown that scaling of the cross section with momentum mismatch occurs for both the ground-state and excited-state data.

3 data tables
Table 1

EX IN 0 MEV REGION (FROM 0 TO 1.5 MEV). ANGULAR BINS OF 5 DEG WIDTH.

Table 2

EX = 7 (FROM 6.5 TO 8.0 MEV). ANGULAR BINS OF 5 DEG WIDTH.

Table 3

EX = 13 (FROM 12.0 TO 13.5 MEV). ANGULAR BINS OF 5 DEG WIDTH.


A Study of the strong coupling constant using W + jets processes

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 75 (1995) 3226-3231, 1995.
Inspire Record 394610 DOI 10.17182/hepdata.42454

The ratio of the number of W+1 jet to W+0 jet events is measured with the D0 detector using data from the 1992–93 Tevatron Collider run. For the W→eν channel with a minimum jet ET cutoff of 25 GeV, the experimental ratio is 0.065±0.003stat±0.007syst. Next-to-leading order QCD predictions for various parton distributions agree well with each other and are all over 1 standard deviation below the measurement. Varying the strong coupling constant αs in both the parton distributions and the partonic cross sections simultaneously does not remove this discrepancy.

1 data table
Table 1

Two values of ALPHA_S corresponds the two different parton distribution functions (pdf) used in extraction of ALPHA_S from the ratio. The dominant systematic error is from the jet energy scale uncertainty.


Precision measurement of the deuteron spin structure function g1(d)

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Rev.Lett. 75 (1995) 25-28, 1995.
Inspire Record 393667 DOI 10.17182/hepdata.19611

We report on a high-statistics measurement of the deuteron spin structure function g1d at a beam energy of 29 GeV in the kinematic range 0.029<x<0.8 and 1<Q2<10 (GeV /c)2. The integral γ1d=∫1g1ddx evaluated at fixed Q2=3 (GeV /c)2 gives 0.042±0.003(stat)±0.004(syst). Combining this result with our earlier measurement of g1p, we find γ1p−γ1n=0.163±0.010(stat)±0.016(syst), which agrees with the prediction of the Bjorken sum rule with O(αs3) corrections, γ1p−γ1n=0.171±0.008. We find the quark contribution to the proton helicity to be Δq=0.30±0.06.

2 data tables
Table 1

No description provided.

Table 2

Values of G1 computed assuming G1/F1 is independent of Q**2 and evaluated at Q**2 = 3 GeV**2.


Measurement of the Z Z gamma and Z gamma gamma couplings in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 75 (1995) 1028, 1995.
Inspire Record 394245 DOI 10.17182/hepdata.42374

We have directly measured the ZZ-gamma and Z-gamma-gamma couplings by studying p pbar --> l+ l- gamma + X, (l = e, mu) events at the CM energy of 1.8$TeV with the D0 detector at the Fermilab Tevatron Collider. A fit to the transverse energy spectrum of the photon in the signal events, based on the data set corresponding to an integrated luminosity of 13.9 pb~-1 ($13.3 pb~-1) for the electron (muon) channel, yields the following 95% confidence level limits on the anomalous CP-conserving ZZ-gamma couplings: -1.9 < h~Z_30 < 1.8 (h~Z_40 = 0), and -0.5 < h~Z_40 < 0.5 (h~Z_30 = 0), for a form-factor scale Lambda = 500 GeV. Limits for the Z-gamma-gamma$ couplings and CP-violating couplings are also discussed.

1 data table
Table 1

The anomalous CP-conserving Z Z GAMMA. CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: h = hi0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n. See article for details.


A Measurement of the ratio sigma x B (p anti-p ---> W ---> e neutrino) / sigma x B (p anti-p ---> Z0 ---> e e) in p anti-p collisions at s**(1/2) = 1800-GeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amendolia, S.R. ; et al.
Phys.Rev.D 52 (1995) 2624-2655, 1995.
Inspire Record 395439 DOI 10.17182/hepdata.42470

We present an analysis of data from p p¯ collisions at a center-of-mass energy of √s =1800 GeV. A measurement is made of the ratio R≡σB(p p¯→W→eν)/σB(p p¯→Z0→ee). The data represent 19.6 pg−1 collected by the Collider Detector at Fermilab during the 1992–1993 collider run of the Fermilab Tevatron. We find R=10.90±0.32(stat)±0.29(syst), and from this value we extract a measurement of the W→eν branching ratio Γ(W→eν)/Γ(W)=0.1094±0.0033(stat)±0.0031(syst). From this branching ratio we set a limit on the top quark mass of mt>62 GeV/c2 at the 95% confidence level. In contrast with direct searches for the top quark, this limit makes no assumptions about the allowed decay modes of the top quark. In addition, we use a calculation of the leptonic width Γ(W→eν) to obtain a value for the W total decay width: Γ(W)=2.064±0.060(stat)±0.059(syst) GeV.

1 data table
Table 1

The cross section ratio contains the branching ratio of W --> E NU and Z0 --> E+ E-. RE = PBAR P --> W+ X.


Comparison of a new calculation of energy-energy correlations with e+ e- ---> hadrons data at the Z0 resonance

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.D 52 (1995) 4240-4244, 1995.
Inspire Record 39718 DOI 10.17182/hepdata.22336

We have compared a new QCD calculation by Clay and Ellis of energy-energy correlations (EEC’s) and their asymmetry (AEEC’s) in e+e− annihilation into hadrons with data collected by the SLD experiment at SLAC. From fits of the new calculation, complete at O(αs2), we obtained αs(MZ2)=0.1184±0.0031(expt)±0.0129(theory) (EEC) and αs(MZ2)=0.1120±0.0034(expt)±0.0036(theory) (AEEC). The EEC result is significantly lower than that obtained from comparable fits using the O(αs2) calculation of Kunszt and Nason.

1 data table
Table 1

The data are compared to the predictions of Monte-Carlo. Two values of ALPHA_S are corresponded the two theoretical models used in the comparison.


Extraction of the ratio F2(n) / F2(p) from muon - deuteron and muon - proton scattering at small x and Q**2

The E665 collaboration Adams, M.R. ; Aid, S. ; Anthony, P.L. ; et al.
Phys.Rev.Lett. 75 (1995) 1466-1470, 1995.
Inspire Record 393866 DOI 10.17182/hepdata.42379

The ratio of the deuteron to proton structure functions is measured at very small Bjorken x (down to 10–6) and for Q2>0.001 GeV2 from scattering of 470 GeV muons on liquid hydrogen and deuterium targets. The ratio F2n/F2p extracted from these measurements is found to be constant, at a value of 0.935±0.008±0.034, for x<0.01. This result suggests the presence of nuclear shadowing effects in the deuteron. The dependence of the ratio on Q2 is also examined; no significant variation is found.

2 data tables
Table 1

F2(N) / F2(P) = 2F2(DEUT)/F2(P) - 1.

Table 2

F2(N) / F2(P) = 2F2(DEUT)/F2(P) - 1. The systematic uncertainty in the Q**2 dependece is negligible as compared to the statistical uncertainty.


phi meson production from p anti-p collisions at s**(1/2) = 1.8-TeV

The E735 collaboration Alexopoulos, T. ; Allen, C. ; Anderson, E.W. ; et al.
Z.Phys.C 67 (1995) 411-416, 1995.
Inspire Record 405368 DOI 10.17182/hepdata.14115

Fermilab experiment E735 located at the CO intersection region of the\(\sqrt s= 1.8\) TeV\(p\bar p\) collider analysed over 900 Φ→K+K− events. Measured were the transverse momentum spectrum, the correlation between the average transverse momentum <pt> and the charged particle multiphcityNc, as well as the probability of Φ production per charged track,NΦ/Nc, versusNc. We have also made an estinate of the total inclusive cross section for Φ mesons,\(\sigma (p\bar p \to \phi X) = 7.3 \pm 2.2 mb\).

3 data tables
Table 1

Corrected phi meson transverse momentum distribution at rapidity = 0.

Table 2

Total inclusive cross section.

Table 3

Ratio of phi to rho0 production in high and low charged particle multiplicity events.