Go, P.T.
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Measurement of the neutral kaon regeneration amplitude in carbon at momenta below 1-GeV/c.

The CPLEAR collaboration Angelopoulos, A. ; Apostolakis, A. ; Aslanides, E. ; et al.
Phys.Lett.B 413 (1997) 422-430, 1997.
Inspire Record 449883 DOI 10.17182/hepdata.47397

The neutral kaon regeneration amplitude in carbon at momenta between 250 and 750 MeV/ c was determined by measuring the interference of inherent and coherently regenerated K S amplitudes. This interference appears in the rates of initially pure (tagged) K 0 and K 0 decaying to π + π − after crossing a carbon absorber.

1 data table
Table 1

No description provided.


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.


Dijet production by color-singlet exchange at the Fermilab Tevatron

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 80 (1998) 1156-1161, 1998.
Inspire Record 447619 DOI 10.17182/hepdata.42182

We report a new measurement of dijet production by color-singlet exchange in pp¯ collisions at s=1.8TeV at the Fermilab Tevatron. In a sample of events with two jets of transverse energy ETjet>20GeV, pseudorapidity in the range 1.8<|ηjet|<3.5, and η1η2<0, we find that a fraction R=[1.13±0.12(stat)±0.11(syst)]% has a pseudorapidity gap within |η|<1 between the jets that can be attributed to color-singlet exchnage. The fraction R shows no significant dependence on ETjet or on the pseudorapidity separation between the jets.

1 data table
Table 1

Q=SS and Q=OS means same-side and opposite-side events.


Search for first generation leptoquark pair production in 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. 79 (1997) 4327-4332, 1997.
Inspire Record 447250 DOI 10.17182/hepdata.42184

We present a search for first generation leptoquark with 110pb^1 of data collected with the CDF detector. We set 95% C.L. cross section limits as a function of the leptoquark mass.

1 data table
Table 1

It is assumed that first generation scalar leptoquark has the ranching ratio to electron and quark equal to 1.


rivet Analysis
Measurement of the differential cross-section for events with large total transverse energy in 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. 80 (1998) 3461-3466, 1998.
Inspire Record 448075 DOI 10.17182/hepdata.42179

We present a measurement of the differential cross section dσ/dΣETjet for the production of multijet events in pp¯ collisions where the sum is over all jets with transverse energy ETjet>ETmin. The measured cross section for events with ΣETjet>320GeV is compared to O(αs3) perturbative QCD predictions and QCD parton shower Monte Carlo predictions. The agreement between the O(αs3) predicted and observed event rates is reasonable for ETmin=100GeV, but poorer for ETmin=20GeV.

2 data tables
Table 1

The ET shown here (unless specified otherwise) is the sum of all the jets' individual ETs. All jets are required to have the absolute values of their pseudorapidity < 4.2 and data are given for two different minimum ET cut-offs.. The errors given are statistical only.

Table 2

Integrated cross sections. Again ET is the sum of the individual ETs of thejets.


Properties of jets in W boson events from 1.8-TeV anti-p p collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 79 (1997) 4760-4765, 1997.
Inspire Record 448076 DOI 10.17182/hepdata.54006

We present a study of events with W bosons and hadronic jets produced in pbar p collisions at a center of mass energy of 1.8 TeV. The data consist of 51400 W^+/- -> e^+/- nu decay candidates from 108 pb^-1 of integrated luminosity collected with the CDF detector at the Tevatron Collider. The cross sections and jet production properties have been measured for W + \geq 1 to \geq 4 jet events. The data are compared to predictions of leading order QCD matrix element calculations with added gluon radiation and simulated fragmentation.

10 data tables
Table 1

W and Z0 + njet cross sections.. Data for Z0 read from the plot.

Table 2

ET distribution of the highest ET jet W + >=1jet production. Data read from the plot.

Table 3

ET distribution of the second highest ET jet W + >=2jet production. Data read from the plot.

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Measurement of the pbar p -> Ks Ks Reaction from 0.6 to 1.9 GeV/c

Evangelista, C. ; Palano, A. ; Drijard, D. ; et al.
Phys.Rev.D 56 (1997) 3803-3810, 1997.
Inspire Record 446452 DOI 10.17182/hepdata.41669

The pbar p -> Ks Ks -> 4pi+/- cross section was measured at incident antiproton momenta between 0.6 and 1.9 GeV/c using the CERN Low Energy Antiproton Ring (LEAR). This investigation was part of a systematic study of in-flight antiproton-proton annihilations into two-neutral-meson final states in a search for hadronic resonances. A coarse scan of the pbar p -> Ks Ks cross section as a function of center-of-mass energy between 1.964 and 2.395 GeV/c^2 and a fine scan of the region surrounding the Xi(2220) are presented. Upper limits on the product branching ratio BR(Xi -> pbar p)BR(Xi -> Ks Ks) are determined for a wide range of mass and width assumptions based on the non-observation of the Xi(2220). A rise in the pbar p -> Ks Ks cross section is observed near 2.15 GeV/c^2, which is consistent with the f2(2150) resonance.

1 data table
Table 1

No description provided.


Search for new gauge bosons decaying into dileptons in 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. 79 (1997) 2192-2197, 1997.
Inspire Record 442760 DOI 10.17182/hepdata.42195

We have searched for heavy neutral gauge bosons (Z′) in dielectron and dimuon decay modes using 110pb−1 of p¯p collisions at s=1.8TeV collected with the Collider Detector at Fermilab. We present a limit on the production cross section times branching ratio of a Z′ boson decaying into dileptons as a function of Z′ mass. For mass MZ′>600GeV/c2, the upper limit is 40 fb at 95% confidence level. We set the lower mass limits of 690, 590, 620, 595, 565, 630, and 600GeV/c2 for ZSM′, Zψ, Zη, Zχ, ZI, ZLR, and ZALRM, respectively.

1 data table
Table 1

M is the mass of ZPRIME boson. Sigma times branching ratio.


Limits on quark - lepton compositeness scales from dileptons produced in 1.8-TeV p anti-p collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 79 (1997) 2198-2203, 1997.
Inspire Record 443871 DOI 10.17182/hepdata.42186

The dilepton mass spectrum in pp¯→l+l−+X interactions is studied using dielectrons (ee) and dimuons (μμ) in 110pb−1 of data collected with the Collider Detector at Fermilab. The data are consistent with standard model predictions. The mass spectrum, being a probe for new physics, is examined for new interactions of quarks and leptons from a common composite structure. Assuming a contact interaction with the conventional coupling g02/4π=1, limits on chiral quark-electron and quark-muon compositeness scales in the range of 2.5 to 4.2 TeV are obtained.

2 data tables
Table 1

Di-electron data and Standard Model event predicitions.

Table 2

Di-muon data and Standard Model event predicitions.


Double parton scattering in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.D 56 (1997) 3811-3832, 1997.
Inspire Record 442259 DOI 10.17182/hepdata.42212

A strong signal for double parton (DP) scattering is observed in a 16pb−1 sample of p¯p→γ/π0+3jets+X data from the CDF experiment at the Fermilab Tevatron. In DP events, two separate hard scatterings take place in a single p¯p collision. We isolate a large sample of data (∼14000events) of which 53% are found to be DP. The process-independent parameter of double parton scattering, σeff, is obtained without reference to theoretical calculations by comparing observed DP events to events with hard scatterings in separate p¯p collisions. The result σeff=(14.5±1.7−2.3+1.7)mb represents a significant improvement over previous measurements, and is used to constrain simple models of parton spatial density. The Feynman x dependence of σeff is investigated and none is apparent. Further, no evidence is found for kinematic correlations between the two scatterings in DP events.

1 data table
Table 1

The cross section for Double Parton scattering comprised of scatterings A and B is written: SIG(DP) = SIG(A)*SIG(B)/CONST(NAME=SIG-EFF). The value of the constant SIG-EFF is measured here.