Alekseev, M.G.
[1000.0, 7000.0]
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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.


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.


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<gW<3.1 for qWe=1 and −0.6<qWe<2.7 for gW=2 at 95% C.L.

1 data table
Table 1

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


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.


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<MW+Mb, we exclude at 95% C.L. the entire (Mtop,MH±) plane for the branching ratio B(H→τν) larger than 75%. We also interpret the results in terms of the parameter tan β of two-Higgs-doublet models.

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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Search for new particles decaying to dijets in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amendolia, S.R. ; et al.
Phys.Rev.Lett. 74 (1995) 3538-3543, 1995.
Inspire Record 392053 DOI 10.17182/hepdata.42387

We have used 19 pb**-1 of data collected with the Collider Detector at Fermilab to search for new particles decaying to dijets. We exclude at 95% confidence level models containing the following new particles: axigluons with mass between 200 and 870 GeV, excited quarks with mass between 80 and 570 GeV, and color octet technirhos with mass between 320 and 480 GeV.

1 data table
Table 1

Here UNSPEC refers to axigluons, excited quarks, colour octet technirhos, ngauge bosons (W' and Z') and diquarks (D and Dc). M is the mass of the new particle (axigluon, q*, ...). Measurements are given to the 95% confidence limit.


Measurement of the B meson differential cross-section, d sigma / d p(T), in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amendolia, S.R. ; et al.
Phys.Rev.Lett. 75 (1995) 1451-1455, 1995.
Inspire Record 393552 DOI 10.17182/hepdata.42432

This paper presents the first direct measurement of the $B$ meson differential cross section, $d\sigma/dp_T$, in $p\overline{p}$ collisions at $\sqrt{s}=1.8$ TeV using a sample of $19.3 \pm 0.7$ pb$~{-1}$ accumulated by the Collider Detector at Fermilab (CDF). The cross section is measured in the central rapidity region $|y| < 1$ for $p_T(B) > 6.0$ GeV/$c$ by fully reconstructing the $B$ meson decays $B~{+}\rightarrow J/\psi K~{+}$ and $B~{0}\rightarrow J/\psi K~{*0}(892)$, where $J/\psi \rightarrow \mu~+\mu~-$ and $K~{*0} \rightarrow K~+ \pi~-$. A comparison is made to the theoretical QCD prediction calculated at next-to-leading order.

3 data tables
Table 1

Charged B meson cross section.

Table 2

Average B meson cross section (including charged and neutral).

Table 3

Total integrated B meson cross section above 6 GeV.


Observation of top quark production in anti-p p collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 74 (1995) 2626-2631, 1995.
Inspire Record 393084 DOI 10.17182/hepdata.42453

We establish the existence of the top quark using a 67 pb^-1 data sample of Pbar-P collisions at Sqrt(s) = 1.8 TeV collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we observe a signal consistent with t-tbar decay to WW b-bbar, but inconsistent with the background prediction by 4.8 sigma. Additional evidence for the top quark is provided by a peak in the reconstructed mass distribution. We measure the top quark mass to be 176 +/-8(stat) +/- 10(sys.) GeV/c^2, and the t-tbar production cross section to be 6.8 +3.6 -2.4 pb.

1 data table
Table 1

Cross section refers to top quark mass equal 176. (+- 8 +- 10) GeV.. Error contains both statistical and systematic uncertainty.


Study of the eta(c) (s wave singlet) state of charmonium formed in anti-p p annihilations and a search for the eta(c)-prime (s wave doublet)

The E760 collaboration Armstrong, T.A. ; Bettoni, D. ; Bharadwaj, V. ; et al.
Phys.Rev.D 52 (1995) 4839-4854, 1995.
Inspire Record 395314 DOI 10.17182/hepdata.42381

The E760 Collaboration performed an experiment in the Antiproton Accumulator at Fermilab to study the two photon decay of the ηc(1 1S0) charmonium state formed in p¯p annihilations. This resulted in a new measurement of the mass Mηc=2988.3−3.1+3.3 MeV/c2 and of the product B(ηc→p¯p)×Γ(ηc→γγ) =(8.1−2.0+2.9) eV. We performed a search for the process p¯p→ηc′(2 1S0)→γγ over a limited range of center-of-mass energies. Since no signal was observed, we derived upper limits on the product of branching ratios B(ηc′→p¯p)×B(ηc′→γγ) in the center-of-mass energy range 3584≤ √s ≤3624 MeV. We observed no signal for the nonresonant process p¯+p→γ+γ and obtain upper limits.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of t anti-t production p anti-p collisions using total transverse energy

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 75 (1995) 3997, 1995.
Inspire Record 396003 DOI 10.17182/hepdata.42358

We analyze a sample of W + jet events collected with the Collider Detector at Fermilab (CDF) in ppbar collisions at sqrt(s) = 1.8 TeV to study ttbar production. We employ a simple kinematical variable "H", defined as the scalar sum of the transverse energies of the lepton, neutrino and jets. For events with a W boson and four or more jets, the shape of the "H" distribution deviates by 3.8 standard deviations from that expected from known backgrounds to ttbar production. However this distribution agrees well with a linear combination of background and ttbar events, the agreement being best for a top mass of 180 GeV/c^2.

1 data table
Table 1

A result of the study of the W + >= 4JETS data sample used in PRL 74, 2626, based on 67 pb-1 of integrated luminosity.. Different fit results due to two choices of the Q2 scale in VECBOS program (see paper).