Dixon, Roger L
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Electroproduction of $\phi$ mesons

Dixon, Roger L. ; Galik, R. ; Herzlinger, M. ; et al.
Phys.Rev.Lett. 39 (1977) 516, 1977.
Inspire Record 120120 DOI 10.17182/hepdata.20949

We report measurements of the electroproduction of ϕ mesons from hydrogen at Q2 values of 0.23, 0.43, and 0.97 GeV2 with |t| varying from 0.125 to 1.3 GeV2 at each Q2 point. The data show no evidence for a Q2 dependence of the slope of the t distribution; the forward cross section falls with increasing Q2 as the square of the ϕ propagator; the decay angular distributions agree with the predictions of s-channel helicity conservation; and the ratio of the longitudinal to the transverse component increases linearly with Q2.

4 data tables
Table 1

'DATA POINT ONE'.

Table 2

'DATA POINT TWO'.

Table 3

'DATA POINT THREE'. POOR STATISTICS - NOT IN PUBLISHED FIGURE.

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Measurement of the Reactions K- p --> Sigma+ pi- and pi- p --> p pi- Near the Backward Direction at 3.0-GeV/c and 5.1-GeV/c

Hoffman, E.W. ; Dixon, Roger L. ; Fletcher, J.M. ; et al.
Phys.Rev.Lett. 35 (1975) 138-141, 1975.
Inspire Record 2233 DOI 10.17182/hepdata.21176

We have measured differential cross sections for K−p→Σ+π− and π−p→pπ− at 3.0 and 5.1 GeV/c near the backward direction. At 3.0 GeV/c both have a dip near −u∼0.1 (GeV/c)2. At 5.1 GeV/c, dσdu for π−p→pπ− falls exponentially with slope 3.8±0.1 (GeV/c)−2 whereas dudσ for K−p→Σ+π− exhibits a decreasing slope for larger |u|. These data are discussed in terms of SU(3), and the relative importance of the helicity-flip and -non-flip amplitudes is investigated.

1 data table
Table 1

No description provided.


Atomic mass dependence of D+- and D0, anti-D0 production in 250-GeV pi+- nucleon interactions

The Fermilab E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 70 (1993) 722-725, 1993.
Inspire Record 341731 DOI 10.17182/hepdata.19741

We measure the relative cross sections for D mesons produced in interactions of π− and π+ beams with targets of Be, Cu, Al, and W. The measurement is based on 1400 fully reconstructed decays of the types D0→K−π+, D+→K−π+π+, and charge conjugates. We find that the cross section for the production of both neutral and charged D’s by either π− or π+ is well fitted by the form Aα where A is the atomic mass and α=1.00±0.05±0.02, where the errors are statistical and systematic, respectively. There is no significant dependence of α on the transverse or longitudinal momentum of the D meson or on the charge of either the incident pion or the produced D mesons.

1 data table
Table 1

No description provided.


SPECTROMETER STUDY OF PHI MESON ELECTROPRODUCTION

Dixon, Roger L. ; Galik, R. ; Larson, D. ; et al.
Phys.Rev.D 19 (1979) 3185, 1979.
Inspire Record 133151 DOI 10.17182/hepdata.24302

We report measurements of the electroproduction of φ mesons from hydrogen at Q2 values of 0.23, 0.43, and 0.97 GeV2 with |t| varying from 0.125 to 1.3 GeV2 at each Q2 point. The data show no evidence for a Q2 dependence of the slope of the t distribution, the forward cross section falls with increasing Q2 as the square of the φ propagator, the decay angular distributions agree with the predictions of s-channel helicity conservation, and the ratio of the longitudinal to the transverse component increases linearly with Q2.

1 data table
Table 1

No description provided.


Feynman-x and transverse momentum dependence of D meson production in 250-GeV pi, K and p nucleon interactions.

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 77 (1996) 2392-2395, 1996.
Inspire Record 418093 DOI 10.17182/hepdata.42291

We measure the differential cross sections with respect to Feynman x ( xF) and transverse momentum ( pT) for π, K, and p-induced charm meson production using fully reconstructed D+, D0, and Ds decays. The shapes of these cross sections are compared to the theoretical predictions for charm quark production of next-to-leading order perturbative QCD using modern parametrizations of the pion and nucleon parton distributions. We observe the differences expected in production induced by projectiles with different gluon distributions, harder distributions being indicated for mesons than for protons.

5 data tables
Table 1

Additional systematic errors of 6 pct, 6 pct and 9 pct respectively for pi, K and p beams.

Table 2

Additional systematic errors of 6 pct, 6 pct and 9 pct respectively for pi, K and p beams.

Table 3

Result of fitting DSIG/dXL spectra with form (1-XL)**POWER.

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Forward cross-sections for production of D+, D0, D/s, D*+ and Lambda/c in 250-GeV pi+-, K+-, and p nucleon interactions.

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 77 (1996) 2388-2391, 1996.
Inspire Record 418771 DOI 10.17182/hepdata.42294

We measure forward cross sections for production of D+, D0, Ds, D*+, and Λc in collisions of π±, K±, and p on a nuclear target. Production induced by different beam particles is found to be the same within statistics. Strange and baryonic final states are seen to contribute appreciably to the total charm cross section, which our measurements indicate is larger than but consistent with QCD predictions. The energy dependence mapped out by these and previous measurements is consistent with theory. Leading-particle asymmetry measurements for K and p-induced charm production are also presented.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Enhanced leading production of D+- and D*+- in 250-GeV pi+- - nucleon interactions

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 72 (1994) 812-815, 1994.
Inspire Record 361344 DOI 10.17182/hepdata.42499

A leading charm meson is one with longitudinal momentum fraction, xF>0, whose light quark (or antiquark) is of the same type as one of the quarks in the beam particles. We report on the production asymmetry, A=[σ(leading-σ(nonleading)]/[σ(leading)+σ(nonleading)] as a function of xF. The data consist of 1500 fully reconstructed D± and D*± decays in Fermilab experiment E 769. We find a significant asymmetry for the production of charm quarks is not expected in perturbative quantum chromodynamics.

2 data tables
Table 1

Asymmetry as function of XL.

Table 2

Asymmetry as function of PT**2.


D*+- production in 250-GeV pi+- N interactions

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.D 49 (1994) R4317-R4320, 1994.
Inspire Record 354345 DOI 10.17182/hepdata.42544

We report results from Fermilab experiment E769 on the differential cross sections of D*± charm vector mesons with respect to Feynman-x (xF) and transverse momentum (PT), and on the atomic mass dependence of the production. The D* mesons were produced by a 250 GeV π beam on a target of Be, Al, Cu, and W foils. The dσdxF distribution is fit by the form ((1−xF)n) with n=3.5±0.3±0.1, the dσdPT2 distribution by exp(−b×PT2) with b=0.70±0.07±0.04 GeV−2, and the cross section A dependence by Aα with α=1.00±0.07±0.02. These results are compared to the equivalent parameters for the production of pseudoscalar D0 and D± charm mesons.

5 data tables
Table 1

Data are in arbitrary units and are the weighted averages bin-by-bin for the 3 D0 modes KPI, K3PI and KPIPI0.

Table 2

Data are in arbitrary units and are the weighted averages bin-by-bin for the 3 modes KPI, K3PI and KPIPI0.

Table 3

Results of fit to DSIG/DXL distribution of the form (1-XL)**POWER in the XL range 0.1 to 0.6.

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Beam flavor dependence in the hadroproduction of D+- and D(s)+- mesons

The E769 collaboration Wallace, A. ; Alves, G.A. ; Amato, S. ; et al.
FERMILAB-CONF-94-184-E, 1994.
Inspire Record 375038 DOI 10.17182/hepdata.43049

None

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Feynman-x and Transverse Momentum Dependence on $D^{\pm}$ and $D^0$, $\bar{D}^0$ Production in 250 GeV $\pi^-$ Nucleon Interactions

The Fermilab E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 69 (1992) 3147-3150, 1992.
Inspire Record 338063 DOI 10.17182/hepdata.19804

We measure the differential cross section with respect to Feynman-x (xF) and transverse momentum (PT) for charm meson production using targets of Be, Al, Cu, and W. In the range 0.1<xF<0.7, dσ/dxF is well fit by the form (1-xF)n with n=3.9±0.3. The difference between n values for D− and D+ is 1.1±0.7. However, we find an asymmetry of 0.18±0.06 favoring the production of D− compared to D+. In the lower PT range, <2 GeV, dσ/dPT2 is well fit by the form exp(-b×PT2) with b=1.03±0.06 GeV−2, while in the higher PT range, 0.8 to 3.6 GeV, it is well fit by the form exp(-b’×PT) with b’=2.76±0.08 GeV−1. The shape of the differential cross section has no significant dependence on atomic mass of the target material.

4 data tables
Table 1

No description provided.

Table 2

Results of fit to DSIG/DXL distribution of the form (1-XL)**POWER in the XL range 0.1 to 0.7. Statistical errors only. Systematic errors are small in comparison.

Table 3

Results of fit to DSIG/DPT**2 distribution of the form exp(-POWER*PT**2) in the PT**2 range 0.0 to 4.0 GeV**2.

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