Bloom, E.D.
Pion-Proton Scattering
[5.0, 10.0]
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Increased Statistics and Observation of the $g(T$), $g(T$)-prime, and $g(T$)-prime-prime 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Hackenburg, R.W. ; et al.
Phys.Lett.B 201 (1988) 568-572, 1988.
Inspire Record 253944 DOI 10.17182/hepdata.30006

In a new experiment we have obtained 3006 new events in the reaction π − p → φφ n, approximately doubling the statistics which now total 6658. A refined partial wave analysis of the φφ system again reveals three resonances (g T , g T′ , g T′' ) with I G J PC =0 + 2 ++ . The absence of the OZI suppression, and the observation of only three J PC =2 ++ states (g T , g T′ , g T′' ) which comprise virtually all the cross section are unusual characteristics of the data. The large φφn signal occurs over a mostly structureless and incoherent φK + K − n background. All these unusual characteristics are well explained if these states are produced by 1–3 glueballs (multigluon resonances).

2 data tables
Table 1

Total cross section plus systematic error supplied by authors.

Table 2

Absolute cross section based on total cross section of 50 +- 15 nb. Errors quoted in Table are statistical only.


Observation of Three 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Longacre, R.S. ; et al.
Phys.Lett.B 165 (1985) 217-221, 1985.
Inspire Record 218668 DOI 10.17182/hepdata.30309

We present data on 3652 analyzed events of the reaction π - p → φφn at 22 GeV/ c . A partial wave analysis has been performed on the φφ system. The results are well represented by three resonances all with quantum numbers I G J PC = 0 + 2 ++ . The absence of the Okubo-Zweig-Iizuka suppression observed in this reaction, the selection of only three J PC =2 ++ states ( g T , g T′ , and g T ″ ) which comprise virtually all of the cross section, and the large φφn signal over a very different φK + K - n background are all well explained if these states are produced by 1–3 glueballs (i.e. multigluon resonances).

1 data table
Table 1

Slope indicates pion exchange process.


Search for $D^*$- Production With a 16-{GeV}/$c \pi^-$ Beam

Chung, S.U. ; Etkin, A. ; Fernow, Richard C. ; et al.
Phys.Rev.Lett. 48 (1982) 785, 1982.
Inspire Record 170568 DOI 10.17182/hepdata.20594

A search for production of D*−'s using the decay chain D0π−, D0→K+π−, was carried out at the Brookhaven National Laboratory multiparticle spectrometer with a 16-GeV/c π− beam and a hydrogen target. At 95% confidence level the upper limits for the product of peripheral production cross section by branching ratio are 2.4 nb for inclusive D*− production and 1.3 nb for the exclusive channel π−p→D*−Λc.

1 data table
Table 1

UPPER LIMIT TO CROSS SECTIONS.


Amplitude Analysis of the K0(s) K0(s) System Produced in the Reaction pi- p ---> K0(s) K0(s) n at 23-GeV/c

Etkin, A. ; Foley, K.J. ; Longacre, R.S. ; et al.
Phys.Rev.D 25 (1982) 1786, 1982.
Inspire Record 169729 DOI 10.17182/hepdata.24030

We have carried out an amplitude analysis of the KS0KS0 system produced in the reaction π−p→KS0KS0n at 23 GeV/c, based on about 15 000 events in the low-t region (|t−tmin|<0.1 GeV2). Below 1.6 GeV/c2, our favored solution is very similar to those from previous analyses. For higher masses, we observe the KS0KS0 decay of the h(2040) meson. In addition, the l=0 partial wave contains a new state, strongly coupled to KS0KS0, with parameters M=1.771−0.053+0.077 GeV/c2 and Γ=0.200−0.009+0.156 GeV/c2. Since this state is most probably I=0, we call it the S*′(1770). We find an f′f production ratio of 0.23−0.13+0.14, and branching ratios for f-meson and h(2040)-meson decays into KK¯ of (3.1−1.7+0.7)% and (0.67−0.15+0.41)%, respectively. We find, in a detailed comparison of our results with those from other experiments, that our solution is compatible with all known features of both charged and neutral KK¯ systems.

1 data table
Table 1

No description provided.


Study of the Reaction pi- p --> K0 Y* at 8.0-GeV/c, 10.7-GeV/c, and 15.7-GeV/c

Foley, K.J. ; Love, W.A. ; Ozaki, S. ; et al.
Phys.Rev.D 15 (1977) 609, 1977.
Inspire Record 4145 DOI 10.17182/hepdata.24625

We present differential and total cross sections for the reactions π−p→K0[Σ(1385)Λ(1405)] and π−p→K0Λ(1520) at incident pion momenta of 8.0, 10.7, and 15.7 GeV/c. Pions from the decay of the forward K0s's were detected in the forward leg of the BNL double-vee spectrometer and the recoil Y* 's were identified by the missing-mass technique.

3 data tables
Table 1

Axis error includes +- 20/20 contribution.

Table 2

Axis error includes +- 20/20 contribution.

Table 3

Axis error includes +- 20/20 contribution.


High Statistics Investigation of K0 K- Decay of a2- Produced by 23-GeV/c pi- on Hydrogen

Margulies, M. ; Kramer, M.A. ; Foley, K.J. ; et al.
Phys.Rev.D 14 (1976) 667, 1976.
Inspire Record 3806 DOI 10.17182/hepdata.24780

We present the results of an experiment to study the reaction π−p→A2−p, A2−→KS0K− at 22.4 and 23.9 GeV/c. We have 3346 KS0K− events in the effective mass region 1.1 to 1.5 GeV, and covering the |t′| interval 0.0 to 1.0 (GeV/c)2. Because of the low background in this channel, we are able to study various |t′| regions, including the region 0.2 to 0.29 (GeV/c)2 in which the original split A2 peak was observed. We find no substructure in any region. We have also derived differential and total cross sections. The differential cross sections are well fitted by the form dσdt′=At′ebt′ with b≈7.0 (GeV/c)−2. The total cross section is in good agreement with the value derived from other experiments that measure the A2−→ρ0π− decay mode.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Neutral associated production by 8, 10.7 and 15.7 gev/c pi- incident on protons

Foley, K.J. ; Love, W.A. ; Ozaki, S. ; et al.
Phys.Rev.D 8 (1973) 27-38, 1973.
Inspire Record 81979 DOI 10.17182/hepdata.22059

We present differential and total cross sections for two reactions: π−p→K0Λ and π−p→K0Σ0. The incident pion momenta were 8, 10.7, and 15.7 GeVc. The results are based on an analysis of approximately 22 600 events of the two reactions where the π+ and π− from the decay of the KS0 were detected in the forward leg of the Double Vee Magnetic Spectrometer. The separation of Λ recoils from Σ0 recoils was accomplished by the missing-mass technique.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

K0(s) k- decay of a2- produced by 20.3-gev/c pi- on hydrogen

Foley, K.J. ; Love, W.A. ; Ozaki, S. ; et al.
Phys.Rev.D 6 (1972) 747-756, 1972.
Inspire Record 73969 DOI 10.17182/hepdata.22252

We present the results of an analysis of data for the reaction π−p→KS0K−p at 20.3-GeV/c incident π momentum. We find that the K0K− effective-mass spectrum shows a single peak in the A2 region which is well fitted by a Breit-Wigner shape. The data in the A2-peak region are inconsistent with the split-A2 shape reported earlier. The distribution in t of the A2 events shows a forward dip followed by an exponential falloff. The A2 decay angular distribution is well fitted by a single resonance with quantum numbers JP=2+. The results of an analysis of the density-matrix elements for this reaction are given.

2 data tables
Table 1

CORRECTED FOR UNSEEN K0 DECAYS AND FOR BREIT-WIGNER RESONANCE TAILS.

Table 2

INCLUDING THE DENSITY MATRIX ELEMENTS OMITTED FROM THIS FIT GIVES NO SIGNIFICANT IMPROVEMENT AND THE NEW PARAMETERS ARE CLOSE TO ZERO. LIM INDICATES FITTED VALUE LIMITED FROM VARIATION BY PHYSICAL CONSTRAINTS FROM OTHER PARAMETERS.