HEPData Search

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Bounds on the CP asymmetry in like sign dileptons from B0 anti-B0 meson decays

The CLEO collaboration Jaffe, D.E. ; Mahapatra, R. ; Masek, G. ; et al.

Phys.Rev.Lett. 86 (2001) 5000-5003, 2001.

Inspire Record 551926 DOI 10.17182/hepdata.47284

We have measured the charge asymmetry in like-sign dilepton yields from B^0 B^0-bar meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a_ll = [N(l+l+) - N(l-l-)]/[N(l+l+) + N[l-l-)] = +0.013 +/- 0.050 +/- 0.005 . We combine this result with a previous, independent measurement and obtain Re(epsilon_B)/(1+|epsilon_B|^2) = +0.0035 +/- 0.0103 +/- 0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon_B.

1 data table

Table 1

CONST(NAME=EPSILON) is CP impurity parameter.

Study of D*+ and search for D**0 production by neutrinos in BEBC

The Big Bubble Chamber Neutrino collaboration Asratvan, A.E. ; Aderholz, M. ; Ammosov, V.V. ; et al.

Z.Phys.C 68 (1995) 43-46, 1995.

Inspire Record 395454 DOI 10.17182/hepdata.47928

Data from BEBC experiments are combined to provide large statistics for neutrino interactions. ChargedD* mesons are produced in (1.22±0.25)% of neutrino and (1.01±0.31)% of antineutrino charged current interactions. The mean fraction of the hadronic laboratory energy taken by theD*+ in these events is 0.59±0.03±0.08. Less than 18% of all chargedD* mesons from (anti)neutrino interactions are found to be daughters ofD**0 (at the 90% confidence level).

4 data tables

Table 1

Mean fractional hadronic energy carried by the D*+- in the laboratory system.

Table 2

Mean value of the Bjorken scaling variable X.

Table 3

Rate of charged D* meson production per charged current neutrino interaction.

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A High Statistics Measurement of the Proton Structure Functions F(2) (x, Q2) and R from Deep Inelastic Muon Scattering at High Q2

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.

Phys.Lett.B 223 (1989) 485-489, 1989.

Inspire Record 276661 DOI 10.17182/hepdata.12557

We present results on a high statistics study of the proton structure functions F 2 ( x , Q 2 ) and R = σ L / σ T measured in deep inelastic scattering of muons on a hydrogen target. The analysis is based on 1.8 × 10 6 events after all cuts, recorded at beam energies of 100, 120, 200 and 280 GeV and covering a kinematic range 0.06 ⩽ x ⩽ 0.80 and 7 GeV 2 ⩽ Q 2 ⩽260 GeV 2 . At small x , we find R to be different from zero in agreement with predictions of perturbative QCD.

105 data tables

Table 1

THE AVERAGE VALUES OF Q**2 AT EACH OF THE X VALUES LISTED IN THIS TABLE ARE 15,20,20,25,30,35,40,45,50,50.

Table 2

R=SIG(L)/SIG(T) IS TAKEN TO BE ZERO.

Table 3

R=SIG(L)/SIG(T) IS TAKEN TO BE ZERO.

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Nuclear Effects in Deep Inelastic Muon Scattering on Deuterium and Iron Targets

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.

Phys.Lett.B 189 (1987) 483-487, 1987.

Inspire Record 244886 DOI 10.17182/hepdata.30200

New Results are presented on nuclear effects in deep inelastic muon scattering on deuterium and iron targets at large Q 2 . The ratio F Fe 2 (x) F D 2 2 (x) measured in the kinematic range 0.06⩽ x ⩽0.70, 14GeV 2 ⩽ Q 2 ⩽70 GeV 2 is in good agreement with earlier measurements in the region of x > 0.25. At lower x , the structure function ratio exhibits an enhancement of ≈5%.

1 data table

Table 1

Q**2 RANGE FOR EACH X BIN IS AS FOLLOWS: 14 TO 20, 16 TO 30, 18 TO 35, 18 TO 46, 20 TO 106, 23 TO 106, 23 TO 150, 26 TO 200, 26 TO 200, 26 TO 200 GEV**2.