Alves, Gilvan
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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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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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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.


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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