Houlden, M.A.
RHO
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Measurement of the spin density matrix for the rho0, K*(892)0 and Phi produced in Z0 decays.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett.B 406 (1997) 271-286, 1997.
Inspire Record 444150 DOI 10.17182/hepdata.47452

The spin density matrix elements for the ϱ 0 , K ∗0 (892) and F produced in hadronic Z 0 decays are measured in the DELPHI detector. There is no evidence for spin alignment of the K ∗0 (892) and F in the region x p ≤ 0.3 ( x p = p p beam ), where ϱ 00 = 0.33 ± 0.05 and ϱ 00 = 0.30 ± 0.04, respectively. In the fragmentation region, x p ≥ 0.4, there is some indication for spin alignment of the ϱ 0 and K ∗0 (892), since ϱ 00 = 0.43 ± 0.05 and ϱ 00 = 0.46 ± 0.08, respectively. These values are compared with those found in meson-induced hadronic reactions. For the F, ϱ 00 = 0.30 ± 0.04 for x p ≥ 0.4 and 0.55 ± 0.10 for x p ≥ 0.7. The off-diagonal spin density matrix element ϱ 1-1 is consistent with zero in all cases.

3 data tables
Table 1

Helicity density matrices elements. The statistical and systematic errors are combined quadratically.

Table 2

Helicity density matrices elements. The statistical and systematic errors are combined quadratically.

Table 3

Helicity density matrices elements. The statistical and systematic errors are combined quadratically.


rivet Analysis
Study of Phi(1020), D*+- and B* spin alignment in hadronic Z0 decays.

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 74 (1997) 437-449, 1997.
Inspire Record 440103 DOI 10.17182/hepdata.47515

Measurements of helicity density matrix elements have been made for the φ(1020), D*± and B* vector mesons in multihadronic Z0 decays in the OPAL experiment at LEP. Results for inclusive φ produced with high energy show evidence for production preferentially in the helicity zero state, with ρ00 = 0.54 ± 0.08, compared to the value of 1/3 expected for no spin alignment. The corresponding element for the D*± has a value of 0.40 ± 0.02, also suggesting a deviation from 1/3. The B* result, with ρ00 = 0.36 ± 0.09, is consistent with no spin alignment. Off-diagonal elements have been measured for the f and D* mesons; for the D* the element Re ρ1−1 is non-zero, indicating non-independent fragmentation of the primary quarks.

4 data tables
Table 1

Helicity density matrices elements. Helicity beam frame is used.

Table 2

Charge conjugated states are understood.

Table 3

Helicity density matrices elements. Charge conjugated states are understood.

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STUDY OF POLARIZATION EFFECTS IN rho0 MESON PRODUCTION IN THE (ANTI)-NEUTRINO CHARGED CURRENT INDUCED QUARK JET

Ammosov, V.V. ; Burtovoy, V.S. ; Gapienko, V.A. ; et al.
Yad.Fiz. 46 (1987) 1673-1679, 1987.
Inspire Record 239544 DOI 10.17182/hepdata.40759

None

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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INVESTIGATION OF THE REACTION ANTI-NEUTRINO N ---> MU+ RHO- N AT HIGH-ENERGIES. (IN RUSSIAN)

Ammosov, V.V. ; Gapienko, V.A. ; Gapienko, G.S. ; et al.
Sov.J.Nucl.Phys. 42 (1985) 236, 1985.
Inspire Record 206937 DOI 10.17182/hepdata.40974

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Results From a $\pi^-$p Slow Proton Trigger Experiment at 12 GeV/c

Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 178 (1981) 197-241, 1981.
Inspire Record 153471 DOI 10.17182/hepdata.34350

A study of the reaction π − p → X − p based on 1.27 × 10 6 events, corresponding to a mean sensitivity of 200 events/μb, is presented. Properties of the exclusive channels π − p → π − π 0 p, π + π − π − p, π + π − π − π 0 p, π + π + π − π − π − p and π + π + π − π − π − π 0 p are discussed.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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K*0 (890) POLARIZATION MEASUREMENTS IN THE HYPERCHARGE EXCHANGE REACTION PI- P ---> K*0 (890) LAMBDA0 / SIGMA0 AT 10-GEV/C

The BARI-BONN-CERN-DARESBURY-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 165 (1980) 383-394, 1980.
Inspire Record 157497 DOI 10.17182/hepdata.34585

K ∗0 (890) production in the hyperchange exchange reaction π − p → K ∗0 (890) Λ 0 Σ 0 at 10 GeV/ c (28 448 events) is discussed. An amplitude analysis in the t ′ range up to 1 GeV 2 shows that the production mechanism is dominated by natural parity exchange (∼84%). Comparisons are made with predictions from a Regge model and a quark model.

2 data tables
Table 1

DENSITY MATRIX ELEMENTS IN THE GOTTFRIED-JACKSON SYSTEM ALLOWING FOR COHERENT S-WAVE BACKGROUND TO P-WAVE BREIT-WIGNER K*(892)0 RESONANCE.

Table 2

No description provided.


Production of phi and f' in 10-GeV/c K- p Interactions

The Bari-Bonn-CERN-Daresbury-Glasgow-Liverpool-Milan-Vienna collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 127 (1977) 384, 1977.
Inspire Record 5792 DOI 10.17182/hepdata.35286

None

4 data tables
Table 1

FOR THE FPRIME A PURE 2+ STATE IS ASSUMED AND ONLY JZ=+1,0,-1 CONTRIBUTIONS ARE CONSIDERED.

Table 2

No description provided.

Table 3

No description provided.

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A High Statistics Study of Omega0 Production

The Carleton-Michigan State-Ohio State-Toronto collaboration Shaevitz, M.H. ; Reay, N.W. ; Reibel, K. ; et al.
Phys.Rev.Lett. 36 (1976) 8, 1976.
Inspire Record 2932 DOI 10.17182/hepdata.37234

We report results from a study of π−p→ω0n at 6.0 GeV/c based on 28 000 events from a charged and neutral spectrometer. Background under the ω0 is only 7%, a large improvement over deuterium-bubble-chamber work. Density matrix elements, projected cross sections, and effective trajectories for natural and unnatural exchanges are presented.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Study of the A2: An Analysis of the Reaction pi- p --> eta pi- p and a Missing Mass Spectrum at 6-GeV/c

Underwood, D. ; Conforto, G. ; Kramer, M.A. ; et al.
Phys.Rev.D 11 (1975) 2345-2366, 1975.
Inspire Record 103078 DOI 10.17182/hepdata.24888

The reaction π−p→X−p, X−→ηπ−, η→γγ has been studied in an optical spark-chamber experiment at the Argonne ZGS (Zero Gradient Synchrotron) at a beam momentum of 6.0 GeV/c and with 0.27≤|t|≤0.42 (GeV/c)2. The ηπ mass spectrum contains about 1400 events in the mass range 0.80

2 data tables
Table 1

No description provided.

Table 2

THIS FIT ASSUMES ALL OTHER DENSITY MATRIX ELEMENTS (RHO(2M) AND RE(RHO(10))) ARE ZERO SINCE THEY ARE QUITE CONSISTENT WITH ZERO IN A FULL FIT. QUOTED ERRORS INCLUDE SYSTEMATIC ERRORS, WHILE STATISTICAL FITTING ERRORS ARE SHOWN SEPARATELY.


The reaction pi+ p ---> omega delta++(1236) at 11.7 gev/c

Evans, D. ; Maddock, R.O. ; Pinter, G.F. ; et al.
Nucl.Phys.B 51 (1973) 205-220, 1973.
Inspire Record 84297 DOI 10.17182/hepdata.32709

For the reaction π + p → ωΔ ++ data on the total cross section ( σ = 61 ± 12 μ b), differential cross sections, spin density matrix elements and statistical tensor elements are given. We observe natural and unnatural parity exchange contributions to the total cross section. We note that the value of ϱ 00 is not zero and in the helicity frame exhibits a dip at t ≈ −0.25 (GeV/ c ) 2 . A qualitative theoretical discussion of our results is presented.

9 data tables
Table 1

CORRECTED FOR BACKGROUND, RESONANCE TAILS AND UNSEEN OMEGA DECAY MODES.

Table 2

NORMALIZED TO THE TOTAL CROSS SECTION. SOME BACKGROUND IS PRESENT.

Table 3

NORMALIZED TO THE TOTAL CROSS SECTION. SOME BACKGROUND IS PRESENT.

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