Smith, L.C.
[1.0, 2.0]
Max results
Sort by Reverse order

Showing 10 of 104 results

The Inclusive jet cross-section 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) 2451-2456, 1999.
Inspire Record 473457 DOI 10.17182/hepdata.42154

We have made a precise measurement of the central inclusive jet cross section at sqrt(s) = 1.8 TeV. The measurement is based on an integrated luminosity of 92 pb-1 collected at the Fermilab Tevatron pbar-p Collider with the D-Zero detector. The cross section, reported as a function of jet transverse energy (ET >= 60 GeV) in the pseudorapidity interval |eta| <= 0.5, is in good agreement with predictions from next-to-leading order quantum chromodynamics.

2 data tables
Table 1

Inclusive cross section for ABS(ETARAP)<0.5. The quoted systematic (DSYS) errors do not include the luminosity uncertainty of 6.1 PCT.

Table 2

Inclusive cross section for 0.1<=ABS(ETARAP)<=0.7. Data are taken from the AIP E-PAPS ftp site shown above. The quoted (DSYS) errors are the total systematic errors including the luminosity uncertainty.


Search for second generation leptoquarks in the dimuon plus dijet channel of p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 81 (1998) 4806-4811, 1998.
Inspire Record 473168 DOI 10.17182/hepdata.42155

We report on a search for second generation leptoquarks (Phi_2) using a data sample corresponding to an integrated luminosity of 110 pb^{-1} collected at the Collider Detector at Fermilab. We present upper limits on the production cross section as a function of Phi_2 mass, assuming that the leptoquarks are produced in pairs and decay into a muon and a quark with branching ratio beta. Using a Next-to-Leading order QCD calculation, we extract a lower mass limit of M_{\Phi_2} > 202 (160) GeV$/c^{2} at 95% confidence level for scalar leptoquarks with beta=1(0.5).

1 data table
Table 1

Cross section times branching ratios.


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.


Measurement of the sigma(W + >= 1 jet) / sigma(W) cross-section ratio from anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 81 (1998) 1367-1372, 1998.
Inspire Record 469969 DOI 10.17182/hepdata.42146

The ratio of the W+≥1 jet cross section to the inclusive W cross section is measured using W±→e±ν events from p¯p collisions at s=1.8TeV. The data are from 108pb−1 of integrated luminosity collected with the Collider Detector at Fermilab. Measurements of the cross section ratio for jet transverse energy thresholds (ETmin) ranging from 15 to 95 GeV are compared to theoretical predictions using next-to-leading-order QCD calculations. Data and theory agree well for ETmin>25GeV, where the predictions lie within 1 standard deviation of the measured values.

1 data table
Table 1

No description provided.


Analyzing powers for pi+- p(pol.) elastic scattering between 87-MeV and 263-MeV.

Hofman, G.J. ; Smith, G.R. ; Ambardar, T. ; et al.
Phys.Rev.C 58 (1998) 3484-3493, 1998.
Inspire Record 483008 DOI 10.17182/hepdata.25722

Analyzing powers for πp elastic scattering were measured using the CHAOS spectrometer at energies spanning the Δ(1232) resonance. This work presents π+ data at the pion kinetic energies 117, 130, 139, 155, 169, 180, 193, 218, 241, and 267 MeV and π− data at 87, 117, 193, and 241 MeV, covering an angular range of 50°<~θc.m.<~180° at the higher energies and 90°<~θc.m.<~180° at the lower energies. Unique features of the spectrometer acceptance were employed to reduce systematic errors. Single-energy phase shift analyses indicate the resulting S11 and S31 phases favor the results of the SM95 phase shift analysis over that of the older KH80 analysis.

18 data tables
Table 1

Measurement of the PI+ analysing power at 117 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Table 2

Measurement of the PI+ analysing power at 139 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Table 3

Measurement of the PI- analysing power at 87 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

More…

Exclusive measurements of pi+- p --> pi+ pi+- n near threshold.

The CHAOS collaboration Kermani, M. ; Amaudruz, P.A. ; Bonutti, F. ; et al.
Phys.Rev.C 58 (1998) 3419-3430, 1998.
Inspire Record 483005 DOI 10.17182/hepdata.25726

The pion induced pion production reactions π±p→π+π±n were studied at projectile incident energies of 223, 243, 264, 284, and 305 MeV, using a cryogenic liquid hydrogen target. The Canadian High Acceptance Orbit Spectrometer was used to detect the two outgoing pions in coincidence. The experimental results are presented in the form of single differential cross sections. Total cross sections obtained by integrating the differential quantities are also reported. In addition, the invariant mass distributions from the (π+π−) channel were fitted to determine the parameters for an extended model based on that of Oset and Vicente-Vacas. We find the model parameters obtained from fitting the (π+π−) data do not describe the invariant mass distributions in the (π+π+) channel.

2 data tables
Table 1

Total cross sections were obtained by integrating the differential cross section over all three variables: M(pi,pi)**2, t, Cos(Theta(pi)).

Table 2

Total cross sections were obtained by integrating the differential cross section over all three variables: M(pi,pi)**2, t, Cos(Theta(pi)).


Determination of the pi+- p --> pi+- pi+ n cross section near threshold.

Lange, J.B. ; Duncan, F. ; Ambardar, A. ; et al.
Phys.Rev.Lett. 80 (1998) 1597-1600, 1998.
Inspire Record 468089 DOI 10.17182/hepdata.19535

The total cross section for the π−p→π−π+n reaction has been measured at incident pion kinetic energies of 200, 190, 184, and 180 MeV. In addition, the π+p→π+π+n reaction was measured at 200 and 184 MeV. A fit of the cross sections by heavy baryon chiral perturbation theory yields values of 8.5±0.6(mπ−3) and 2.5±0.1(mπ−3) for the reaction matrix elements A10 and A32, which correspond to values for the s-wave isospin-0 and isospin-2 π−π scattering lengths of a0=0.23±0.08(mπ−1) and a2=−0.031±0.008(mπ−1), respectively.

1 data table
Table 1

No description provided.


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.


Measurement of the top quark mass and t anti-t production cross-section from dilepton events at the collider detector at Fermilab

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 80 (1998) 2779-2784, 1998.
Inspire Record 449926 DOI 10.17182/hepdata.42173

We present an analysis of dilepton events originating from top-antitop production in proton-antiproton collisions at sqrt{s}=1.8 TeV at the Fermilab Tevatron Collider. The sample corresponds to an integrated luminosity of 109+-7 pb^{-1}. We observe 9 candidate events, with an estimated background of 2.4+-0.5 events. We determine the mass of the top quark to be M_top = 161+-17(stat.)+-10(syst.) GeV/c^2. In addition we measure a top-antitop production cross section of 8.2+4.4-3.4 pb (where M_top = 175 GeV/c^2 has been assumed for the acceptance estimate).

1 data table
Table 1

No description provided.