Amidei, D.
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Search for the top quark decaying to a charged Higgs boson in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2667-2671, 1994.
Inspire Record 383998 DOI 10.17182/hepdata.50929

We present the results of a search in p¯p collisions at s=1.8 TeV for the top quark decaying to a charged Higgs boson (H±). We search for dilepton final states from the decay chain tt¯→HH (or HW, or WW) + bb¯→ll+X. In a sample of 19.3 pb−1 collected during 1992-93 with the Collider Detector at Fermilab, we observe 2 events with a background estimation of 3.0 ± 1.0 events. Limits at 95% C.L. in the (Mtop,MH±) plane are presented. For the case Mtop

6 data tables
Table 1

Upper limits on the cross section at 95PCT CL. CONST(TAN(BETA)) is model parameter describing the charged Higgs decay (see text).

Table 2

Upper limits on the cross section at 95PCT CL. CONST(TAN(BETA)) is model pameter describing the charged Higgs decay (see text).

Table 3

Upper limits on the cross section at 95PCT CL. CONST(TAN(BETA)) is model pameter describing the charged Higgs decay (see text).

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Measurement of the B meson and b quark cross-sections at s**(1/2) = 1.8-TeV using the exclusive decay B0 ---> J / psi K*0 (892)

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 50 (1994) 4252, 1994.
Inspire Record 382305 DOI 10.17182/hepdata.51050

This paper reports the measurement of the B meson and b quark cross sections through the decay chain B0→J/ψ K*(892)0, J/ψ→μ+μ−, K*(892)0→K+π−, using 4.3 pb−1 of data collected at the Collider Detector at Fermilab in p¯p collisions at qrts=1.8 TeV. We obtain σB=1.5±0.7(stat)±0.6(syst) μb for B0 mesons with transverse momentum PT>9.0 GeV/c and rapidity ‖y‖<1.0. Using this result, we find σb=3.7±1.6(stat)±1.5(syst) μb for b quarks with PT>11.5 GeV/c and rapidity ‖y‖<1.0. The b quark cross section is compared to next-to-leading order QCD calculations and previous measurements.

2 data tables
Table 1

B0 meson cross section.

Table 2

Bquark cross section.


The Charge asymmetry in W boson decays produced in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 74 (1995) 850-854, 1995.
Inspire Record 379592 DOI 10.17182/hepdata.42427

The charge asymmetry has been measured using $19,039W$ decays recorded by the CDF detector during the 1992-93 run of the Tevatron Collider. The asymmetry is sensitive to the ratio of $d$ and $u$ quark distributions to $x<0.01$ at $Q~2 \approx M_W~2$, where nonperturbative effects are minimal. It is found that of the two current sets of parton distributions, those of Martin, Roberts and Stirling (MRS) are favored over the sets most recently produced by the CTEQ collaboration. The $W$ asymmetry data provide a stronger constraints on $d/u$ ratio than the recent measurements of $F_2~{\mu n}/F_2~{\mu p}$ which are limited by uncertainties originating from deutron corrections.

1 data table
Table 1

Charge asymmetry defined as (DSIG(Q=L+)/DYRAP - DSIG(Q=L-)/DYRAP)/ (DSIG(Q=L+)/DYRAP + DSIG(Q=L-)/DYRAP). Here LEPTON are E and MU.


b anti-b quark pair correlations in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
FERMILAB-PUB-94-131-E, 1994.
Inspire Record 380743 DOI 10.17182/hepdata.42477

None

1 data table
Table 1

No description provided.


Measurement of W - photon couplings with CDF in p - anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 74 (1995) 1936-1940, 1995.
Inspire Record 377331 DOI 10.17182/hepdata.42429

We report on a study of W+ photon production in approximately 20 pb−1 of p−p¯ collisions at s=1.8 TeV recorded with the Collider Detector at Fermilab. Our results are in good agreement with standard model expectations and are used to obtain limits on anomalous CP-conserving WWγ couplings of −2.3<Δκ<2.2 for λ=0 and −0.7<λ<0.7 for Δκ=0 at 95% C.L. We obtain the same limits for CP-violating couplings. These results provide limits on the higher-order electromagnetic moments of the W boson of 0.8

1 data table
Table 1

E + MU combined. Limits on CP-conserving anomalous WWGAMMA couplings DELTA(K) and LAMBDA (see paper).


A Precision measurement of the prompt photon cross-section in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2662-2666, 1994.
Inspire Record 375582 DOI 10.17182/hepdata.19680

A prompt photon cross section measurement from the Collider Detector at Fermilab experiment is presented. Detector and trigger upgrades, as well as 6 times the integrated luminosity compared with our previous publication, have contributed to a much more precise measurement and extended PT range. As before, QCD calculations agree qualitatively with the measured cross section, but the data has a steeper slope than the calculations.

1 data table
Table 1

Note that the sytematic uncertainties are approximately 100 pct correlated bin to bin.


W boson + jet angular distribution in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2296-2300, 1994.
Inspire Record 374152 DOI 10.17182/hepdata.42492

The W+jet angular distribution is measured using W→eν events recorded with the Collider Detector at Fermilab (CDF) during the 1988-89 and 1992-93 Tevatron runs. The data agree well with both a leading order and a next-to-leading order theoretical prediction. The shape of the angular distribution is similar to that observed in photon + jet data and significantly different from that observed in dijet data.

2 data tables
Table 1

Data normalized to 1 in the cos(theta) range -0.6 to 0.6.

Table 2

Data normalized to 1 in the abs(cos(theta)) range <0.3.


Evidence for top quark production 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 50 (1994) 2966-3026, 1994.
Inspire Record 372952 DOI 10.17182/hepdata.50086

We present the results of a search for the top quark in 19.3 pb−1 of p¯p collisions at √s =1.8 TeV. The data were collected at the Fermilab Tevatron collider using the Collider Detector at Fermilab (CDF). The search includes standard model tt¯ decays to final states eeνν¯, eμνν¯, and μμνν¯ as well as e+ν+jets or μ+ν+jets. In the (e,μ)+ν+jets channel we search for b quarks from t decays via secondary vertex identification and via semileptonic decays of the b and cascade c quarks. In the dilepton final states we find two events with a background of 0.56−0.13+0.25 events. In the e,μ+ν+jets channel with a b identified via a secondary vertex, we find six events with a background of 2.3±0.3. With a b identified via a semileptonic decay, we find seven events with a background of 3.1±0.3. The secondary vertex and semileptonic-decay samples have three events in common. The probability that the observed yield is consistent with the background is estimated to be 0.26%. The statistics are too limited to firmly establish the existence of the top quark; however, a natural interpretation of the excess is that it is due to tt¯ production. We present several cross-checks. Some support this hypothesis; others do not. Under the assumption that the excess yield over background is due to tt¯, constrained fitting on a subset of the events yields a mass of 174±10−12+13 GeV/c2 for the top quark. The tt¯ cross section, using this top quark mass to compute the acceptance, is measured to be 13.9−4.8+6.1 pb.

1 data table
Table 1

Cross section refers to top quark mass equals 174 +- 10 +13 - 12 GeV. Two events in the dilepton final states and six events in the electron or muon nu jets final states.


rivet Analysis
Evidence for color coherence in p anti-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 50 (1994) 5562-5579, 1994.
Inspire Record 374155 DOI 10.17182/hepdata.42448

Color coherence effects in pp¯ collisions are observed and studied with CDF, the Collider Detector at the Fermilab Tevatron collider. We demonstrate these effects by measuring spatial correlations between soft and leading jets in multijet events. Variables sensitive to interference are identified by comparing the data to the predictions of various shower Monte Carlo programs that are substantially different with respect to the implementation of coherence.

8 data tables
Table 1

Observed normalised transverse energy distribution of the leading (highest ET) jet.. Data read from plot in the preprint.

Table 2

Observed normalised transverse energy distribution of the second highest ET jet.. Data read from plot in the preprint.

Table 3

Observed normalised pseudorapidity distribution of the third highest ET jet.. Data read from plot in the preprint.

More…

Measurement of the ratio sigma B (W ---> e neutrino) / sigma B (Z0 ---> e+ e-) in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 220-224, 1994.
Inspire Record 373743 DOI 10.17182/hepdata.50100

We present a measurement of the ratio σB(W→eν)σB(Z0→e+e−) in p¯p collisions at s=1.8 TeV The data represent an integrated luminosity of 21.7 pb−1 from the 1992-1993 run of the Collider Detector at Fermilab. We find σB(W→eν)σB(Z0→e+e−)=10.90±0.32(stat)±0.29(syst). From this value, we extract a value for the W width, Γ(W)=2.064±0.061(stat)±0.059(syst) GeV, and the branching ratio, Γ(W→eν)Γ(W)=0.1094±0.0033(stat)±0.0031(syst), and we set a decay-mode-independent limit on the top quark mass mtop>62 GeV/c2 at the 95% C.L.

1 data table
Table 1

No description provided.