Abreu, P.
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First measurement of the neutron electromagnetic form-factor in the timelike region

Antonelli, A. ; Baldini, R. ; Bertani, M. ; et al.
Phys.Lett.B 313 (1993) 283-287, 1993.
Inspire Record 359376 DOI 10.17182/hepdata.28867

The first measurement of the neutron form factor in the time-like region has been performed by the FENICE experiment at the ADONE e + e − storage ring. Results at q 2 = 4.0 and 4.4 (GeV/ c ) 2 , together with a new measurement of the proton form factor are presented here.

2 data tables
Table 1

Neutron form factor and cross section.

Table 2

Preliminary analysis of proton form factor and cross section.


Mass and transverse momentum dependence of dielectron production in p + d and p + p collisions at 4.9-GeV

The DLS collaboration Huang, H.Z. ; Beedoe, S. ; Bougteb, M. ; et al.
Phys.Rev.C 49 (1994) 314-319, 1994.
Inspire Record 356615 DOI 10.17182/hepdata.38156

Dielectron production in p+d and p+p collisions at the beam kinetic energy of 4.9 GeV has been measured with the Dilepton Spectrometer. Features of the dielectron cross section have been studied with cuts on the mass and transverse momentum of the pairs. The spectra for several regions of phase space are presented as a function of the pair mass and transverse momentum.

8 data tables
Table 1

Mass distribution.

Table 2

Mass distribution.

Table 3

Transverse momentum distribution.

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Search for quark compositeness, axigluons and heavy particles using the dijet invariant mass spectrum observed in p anti-p collisions

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Akimoto, H. ; et al.
Phys.Rev.Lett. 71 (1993) 2542-2546, 1993.
Inspire Record 356676 DOI 10.17182/hepdata.19713

The dijet invariant mass distribution has been measured in the region between 140 and 1000 GeV/c2, in 1.8 TeV p p¯ collisions. Data collected with the Collider Detector at Fermilab show agreement with QCD calculations. A limit on quark compositeness of Λc>1.3 TeV is obtained. Axigluons with masses between 240 and 640 GeV/c2 are excluded at 95% C.L. if we assume ten open decay channels. Model-independent limits on the production of heavy particles decaying into two jets are also presented.

1 data table
Table 1

No description provided.


Axial and pseudoscalar nucleon form-factors from low-energy pion electroproduction

Choi, Seonho ; Estenne, V. ; Bardin, G. ; et al.
Phys.Rev.Lett. 71 (1993) 3927-3930, 1993.
Inspire Record 360772 DOI 10.17182/hepdata.19697

The cross section for exclusive π+ electroproduction on the proton has been measured near threshold for the first time at two different values of the virtual photon polarization (ɛ∼0.2 and ɛ∼0.7). Using the low energy theorem for this reaction we deduce the axial and pseudoscalar weak form factors GA and GP at ‖t‖=0.073, 0.139, and 0.179 (GeV/c)2. The slope of GA agrees with the value obtained in neutrino experiments. GP satisfies the pion pole dominance hypothesis, which is thus verified for the first time in this range of transfer.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of bottom quark production in 1.8-TeV p anti-p collisions using semileptonic decay muons

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.Lett. 71 (1993) 2396-2400, 1993.
Inspire Record 356237 DOI 10.17182/hepdata.19723

We present a measurement of the b-quark cross section in 1.8 TeV p-p¯ collisions recorded with the Collider Detector at Fermilab using muonic b-quark decays. In the central rapidity region (‖yb‖<1.0), the cross section is 295±21±75 nb (59±14±15 nb) for pTb>21 GeV/c (29 GeV/c). Comparisons are made to previous measurements and next-to-leading order QCD calculations.

1 data table
Table 1

No description provided.


Polarization of $\Sigma^+$ and $\bar{\Sigma^-}$ Hyperons Produced by 800-GeV/c Protons

The E761 collaboration Morelos Pineda, Antonio ; Albuquerque, I.F. ; Bondar, N.F. ; et al.
Phys.Rev.Lett. 71 (1993) 2172-2175, 1993.
Inspire Record 356301 DOI 10.17182/hepdata.19722

We have mesured the polarization of 375-GeV/c Σ+ and Σ¯ − hyperons produced by 800-GeV/c protons incident on a Cu target. We find that the Σ+ polarization rises with increasing pt to a maximum of 16% at pt=1.0 GeV/c and then decreases to 10% at pt=1.8 GeV/c. We compare this Σ+ polarization with data at lower energies. The Σ¯ − polarization has been measured for the first time. It has the same sign as the Σ+ but smaller magnitude in a similar kinematical region.

4 data tables
Table 1

Data from Horizontal targeting.

Table 2

Data from Vertical targeting.

Table 3

Data from Horizontal targeting.

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Measurement of Drell-Yan electron and muon pair differential cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 49 (1994) R1-R6, 1994.
Inspire Record 355927 DOI 10.17182/hepdata.42543

We measure the Drell-Yan differential cross section d2σdMdy||y|<1 over the mass range 11

3 data tables
Table 1

Dielectron differential cross section.

Table 2

Dimuon differential cross section.

Table 3

Drell-Yan differential cross section for combined dielectron and dimuon data. Error includes both statistics and systematics.


Search for excited electrons using the ZEUS detector

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Phys.Lett.B 316 (1993) 207-218, 1993.
Inspire Record 355574 DOI 10.17182/hepdata.45106

This paper reports a search for excited electrons at the HERA electron-proton collider. In a sample corresponding to an integrated luminosity of 26 nb − , no evidence was found for any resonant state decaying into e − γ , ν W − or e − Z 0 . Limits on the coupling strength of an excited electron have been determined for masses between 45 and 225 GeV. This study also reports the observation of the wide-angle e γ Compton scattering process.

1 data table
Table 1

No description provided.


Direct photon production in anti-p p and p p interactions at s**(1/2) = 24.3-GeV

The UA6 collaboration Sozzi, G. ; Ballocchi, G. ; Bernasconi, A. ; et al.
Phys.Lett.B 317 (1993) 243-249, 1993.
Inspire Record 358422 DOI 10.17182/hepdata.28782

Inclusive direct photon invariant cross sections have been measured in both p p and pp collisions at √ s = 24.3 GeV at the CERN SPS, permitting the first measurement of the difference of the p p and pp cross sections. The direct photon cross section in p p collisions has been found to be systematically larger than that in pp collisions, which indicates a significant contribution of the q q annihilation term as predicted by theoretical calculations.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of inclusive jet cross-sections in photoproduction at HERA

The H1 collaboration Abt, I. ; Ahmed, T. ; Andreev, V. ; et al.
Phys.Lett.B 314 (1993) 436-444, 1993.
Inspire Record 356741 DOI 10.17182/hepdata.28821

The inclusive jet cross section in photoproduction has been measured as a function of transverse energy and pseudorapidity using the H 1 detector at the HERA electron-proton collider. The results are compared with leading order QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.