Meshchanin, A.P.
[10.0, 12.0]
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The Dijet mass spectrum and a search for quark compositeness in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 2457-2462, 1999.
Inspire Record 473420 DOI 10.17182/hepdata.42143

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level.

2 data tables
Table 1

Dijet cross section for ABS(ETARAP)<1.0.

Table 2

Ratio of cross sections for ABS(ETARAP) < 0.5 / 0.5 < ABS(ETARAP) < 1.0.


Small angle J / psi production in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 35-40, 1999.
Inspire Record 473954 DOI 10.17182/hepdata.42141

This paper presents the first measurement of the inclusive J/Psi production cross section in the forward pseudorapidity region 2.5<|eta|<3.7 in ppbar collisions at sqrt(s)=1.8TeV. The results are based on 9.8 pb-1 of data collected using the D0 detector at the Fermilab Tevatron Collider. The inclusive J/Psi cross section for transverse momenta between 1 and 16 GeV/c is compared with theoretical models of charmonium production.

1 data table
Table 1

Only statistical errors are shown. Cross section tines branching ratio.


Search for first generation scalar leptoquark pairs in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 80 (1998) 2051-2056, 1998.
Inspire Record 450538 DOI 10.17182/hepdata.42159

We have searched for first generation scalar leptoquark (LQ) pairs in the enu+jets channel using ppbar collider data (integrated luminosity= 115 pb^-1) collected by the DZero experiment at the Fermilab Tevatron during 1992-96. The analysis yields no candidate events. We combine the results with those from the ee+jets and nunu+jets channels to obtain 95% confidence level (CL) upper limits on the LQ pair production cross section as a function of mass and of beta, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively.

1 data table
Table 1

The cross section values are extracted with the assumption that BR(LQ --> EQUARK) = 1/2.


Limits on W W Z and W W gamma couplings from p anti-p ---> e neutrino jet jet X events at s**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 79 (1997) 1441-1446, 1997.
Inspire Record 443148 DOI 10.17182/hepdata.42199

We present limits on anomalous WWZ and WW-gamma couplings from a search for WW and WZ production in p-bar p collisions at sqrt(s)=1.8 TeV. We use p-bar p -> e-nu jjX events recorded with the D0 detector at the Fermilab Tevatron Collider during the 1992-1995 run. The data sample corresponds to an integrated luminosity of 96.0+-5.1 pb~(-1). Assuming identical WWZ and WW-gamma coupling parameters, the 95% CL limits on the CP-conserving couplings are -0.33<lambda<0.36 (Delta-kappa=0) and -0.43<Delta-kappa<0.59 (lambda=0), for a form factor scale Lambda = 2.0 TeV. Limits based on other assumptions are also presented.

1 data table
Table 1

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n.


Study of quasiexclusive neutral meson production in p N interactions at E(p) = 70-GeV in the deep fragmentation region.

The SPHINX collaboration Golovkin, S.V. ; Kozhevnikov, A.P. ; Kubarovsky, V.P. ; et al.
Z.Phys.A 359 (1997) 327-335, 1997.
Inspire Record 445405 DOI 10.17182/hepdata.40690

Quasiexclusive neutral meson production in pN-interactions is studied in experiments with the SPHINX facility operating in a proton beam from the IHEP accelerator (Ep=70 GeV). The cross sections and the parameters of the differential distributions for πo, ω, η and Ko production in the deep fragmentation region (xF > 0.79 ÷ 0.86) are presented. The results show that such proton quasiexclusive reactions with baryon exchange may be promising in searches for exotic mesons.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Data on the graph only.

More…

Search for anomalous W W and W Z production 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. 77 (1996) 3303-3308, 1996.
Inspire Record 419962 DOI 10.17182/hepdata.42290

We present results from a search for anomalous WW and WZ production in ppbar collisions at sqrt(s) = 1.8 TeV. We used ppbar->evjjX events observed during the 1992-1993 run of the Fermilab Tevatron collider, corresponding to an integrated luminosity of 13.7 +- 0.7 pb^-1. A fit to the transverse momentum spectrum of the W boson yields direct limits on the CP-conserving anomalous WWgamma and WWZ coupling parameters of -0.9 &lt; delta kappa &lt; 1.1 (with lambda = 0) and -0.6 &lt; lambda &lt; 0.7 (with delta kappa = 0) at the 95% confidence level, for a form factor scale Lambda = 1.5 TeV, assuming that the WWgamma and WWZ coupling parameters are equal.

1 data table
Table 1

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n.


Investigation of the OZI selection rule for connected quark diagrams in hadronic processes. III: Diffractive Phi and omega production in p N collisions at 70-GeV.

The SPHINX collaboration Vavilov, D.V. ; Viktorov, V.A. ; Golovkin, S.V. ; et al.
Phys.Atom.Nucl. 59 (1996) 1186-1190, 1996.
Inspire Record 406501 DOI 10.17182/hepdata.40526

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

This ratio is corrected for the different phase space of the (P PHI) and (P OMEGA) system.


Further study of the quasi-exclusive reactions of the neutral mesons production by 70-GeV protons in p N interactions in the deep fragmentation region. (Revised version, in Russian)

The SPHINX collaboration Vavilov, D.V. ; Viktorov, V.A. ; Golovkin, S.V. ; et al.
IFVE-95-138, 1995.
Inspire Record 406502 DOI 10.17182/hepdata.40645

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Search for N (phi) (1960) baryon

The SPHINX collaboration Balats, M.Ya. ; Belyaev, I.M. ; Dorofeev, V.A. ; et al.
Z.Phys.C 61 (1994) 399-405, 1994.
Inspire Record 376444 DOI 10.17182/hepdata.14371

In the experiments at the SPHINX facility in the 70 GeV proton beam of the IHEP accelerator the diffractive production reactionsp+N→[Σ(1385)0K+] +N andp+N→[Σ(1385)0K+]+N+ (neutral particles) were studied. In the effective mass spectra of the [Σ(1385)0K+] system in these processes there were no signals from the anomalously narrow baryon stateNϕ (1960) which had been observed earlier in the measurement at the BIS-2 setup.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Search for heavy pentaquark exotic baryons with hidden strangeness in the p + N ---> (p Phi) + N and p + N ---> (Lambda (1520) K+) + N reactions at E(p) = 70-GeV

The SPHINX collaboration Dorofeev, V.A. ; Golovkin, S.V. ; Kozhevnikov, A.P. ; et al.
Phys.Atom.Nucl. 57 (1994) 227-237, 1994.
Inspire Record 385732 DOI 10.17182/hepdata.40688

None

2 data tables
Table 1

No description provided.

Table 2

The upper limits for production of EXOTIC-NUCLEON with narrow width (<50 MeV). Linear A-dependence of the cross section is assumed.