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G. S. Adams,
T Adams,
Z. Bar-Yam,
J. M. Bishop,
V. A. Bodyagin,
D S Brown,
N M Cason,
M. Chasse,
S U Chung,
J. P. Cummings, [......],
D. L. Stienike,
J S Suh,
S. A. Taegar,
A. Tomaradze,
I. N. Vardanyan,
D P Weygand,
D B White,
H. J. Willutzki,
M Witkowski,
A. A. Yershov
[show abstract]
[hide abstract]
ABSTRACT: The exclusive reaction $\pi^- p \to \eta \pi^0 n$, $\eta \to \pi^+ \pi^- \pi^0$ at 18 GeV$/c$ has been studied with a partial wave analysis on a sample of 23~492 $\eta \pi^0 n$ events from BNL experiment E852. A mass-dependent fit is consistent with a resonant hypothesis for the $P_+$ wave, thus providing evidence for a neutral exotic meson with $J^{PC} = 1^{-+}$, a mass of $1257 \pm 20 \pm 25$ MeV$/c^2$, and a width of $354 \pm 64 \pm 60$ MeV$/c^2$. New interpretations of the meson exotics in neutral $\eta \pi^0$ system observed in E852 and Crystal Barrel experiments are discussed.
01/2007;
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G S Adams,
T Adams,
Z Bar-Yam,
J M Bishop,
V A Bodyagin,
D S Brown,
N M Cason,
M Chasse,
S U Chung,
J P Cummings, [......],
D L Stienike,
J S Suh,
S A Taegar,
A Tomaradze,
I N Vardanyan,
D P Weygand,
D B White,
H J Willutzki,
M Witkowski,
A A Yershov
[show abstract]
[hide abstract]
ABSTRACT: The status of spin-exotic mesons is reviewed. There is now compelling evidence for at least three π1 states between one and two GeV. Preliminary results from the reaction π−p → π+π+π−π−π0p show structure in the exotic waves corresponding to IGJPC = 0−2+−.
Journal of Physics Conference Series 07/2005; 9(1):136.
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M Lu,
G S Adams,
T Adams,
Z Bar-Yam,
J M Bishop,
V A Bodyagin,
D S Brown,
N M Cason,
S U Chung,
J P Cummings, [......],
D L Stienike,
J S Suh,
S A Taegar,
A Tomaradze,
I N Vardanyan,
D P Weygand,
D B White,
H J Willutzki,
M Witkowski,
A A Yershov
[show abstract]
[hide abstract]
ABSTRACT: A partial-wave analysis of the mesons from the reaction pi(-)p --> pi(+)pi(-)pi(-)pi(0)pi(0)p has been performed. The data show b(1)pi decay of the spin-exotic states pi(1)(1600) and pi(1)(2000). Three isovector 2(-+) states were seen in the omegarho(-) decay channel. In addition to the well known pi(2)(1670), signals were also observed for pi(2)(1880) and pi(2)(1970).
Physical Review Letters 01/2005; 94(3):032002. · 7.37 Impact Factor
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E I Ivanov,
D L Stienike,
D I Ryabchikov,
G S Adams,
T Adams,
Z Bar-Yam,
J M Bishop,
V A Bodyagin,
D S Brown,
N M Cason, [......],
N B Sinev,
J A Smith,
S A Taegar,
A Tomaradze,
I N Vardanyan,
D P Weygand,
D B White,
H J Willutzki,
M Witkowski,
A A Yershov
[show abstract]
[hide abstract]
ABSTRACT: An amplitude analysis of an exclusive sample of 5765 events from the reaction pi- p-->eta'pi- p at 18 GeV/c is described. The eta'pi- production is dominated by natural parity exchange and by three partial waves: those with J(PC) = 1(-+), 2(++), and 4(++). A mass-dependent analysis of the partial-wave amplitudes indicates the production of the a2(1320) meson as well as the a4(2040) meson, observed for the first time decaying to eta'pi-. The dominant, exotic (non- qq) 1(-+) partial wave is shown to be resonant with a mass of 1.597+/-0.010(+0.045)(-0.010) GeV/c2 and a width of 0.340+/-0.040+/-0.050 GeV/c2. This exotic state, the pi1(1600), is produced with a t dependence which is different from that of the a2(1320) meson, indicating differences between the production mechanisms for the two states.
Physical Review Letters 04/2001; 86(18):3977-80. · 7.37 Impact Factor
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J. M. Bishop,
R. Cady,
N M Cason,
J. Gress, J M LoSecco,
J J Manak,
A H Sanjari,
W D Shephard,
D. L. Stienike,
S. A. Taegar,
D. R. Thompson,
R. W. Hackenburg
[show abstract]
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ABSTRACT: The design, construction, and performance of a 198-element CsI detector built for Brookhaven experiment E852 is described. Design considerations for the array included such factors as rate, magnetic field, sensitivity and acceptance. Signals were obtained with a photodiode/preamplifier combination using PIN photodiodes. Data were taken over the course of two runs during the summers of 1993 and 1994. A calibration procedure using halo-muons is described. The gain, energy resolution, and position resolution of the detector are discussed. Finally, the ability of the detector to be used as a low energy photon veto is illustrated using the data. PACS numbers: xx.xx Typeset using REVT E X I. INTRODUCTION Brookhaven experiment E852 has been under design and construction for several years and had its first large-scale data run in the summer of 1994. The purpose of the experiment is to search for exotic mesons such as glueballs, hybrids, and multiquark states. The experiment will concentrat...
11/1995;
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J M LoSecco,
T Adams,
J. M. Bishop,
N M Cason,
J J Manak,
A H Sanjari,
W D Shephard,
D. L. Stienike,
S. A. Taegar,
D. R. Thompson, [......],
D S Brown,
T. K. Pedlar,
K. K. Seth,
J. Wise,
D. Zhao,
G. S. Adams,
J. Napolitano,
M Nozar,
J. A. Smith,
M Witkowski
[show abstract]
[hide abstract]
ABSTRACT: CPVC DEA DCM1...5 TPX3 C8 TDX4 LGD TPX1 DCM6 CIA Cesium Iodide Endcap ( 18 elements) CIB Cesium Iodide Barrel 180 elements) TCYL Cylindrical Drift Chamber CPVB,C Scintillation counters TPX1,2,3 Proportional Wire Chambers DEA Lead-Scintillator sandwich DCM1...6 MPS Drift Chambers C 8 Threshold Cerenkov ( 11 cells) TDX4 Drift Chamber LGD Pb-Glass Detector 3053 4x4 cm elements) BV EV BV Beam Veto EV Elastic Veto Not to scale - The target to LGD distance is 5 meters shaded regionindicates magnetic field TPX2 Figure 1: Schematic View of the Detector Introduction Quantum Chromodynamics (QCD) is a theory of interacting quarks and gluons. The distinctive charge and color properties are responsible for the quantum numbers of most of the known hadr
11/1995;
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J M LoSecco,
T Adams,
J. M. Bishop,
N M Cason,
J J Manak,
A H Sanjari,
W D Shephard,
D. L. Stienike,
S. A. Taegar,
D. R. Thompson, [......],
D S Brown,
T. K. Pedlar,
K. K. Seth,
J. Wise,
D. Zhao,
G. S. Adams,
J. Napolitano,
M Nozar,
J. A. Smith,
M Witkowski
[show abstract]
[hide abstract]
ABSTRACT: The recent search for non $q \bar{q}$ mesons in $\pi^{-}p$ interactions at Brookhaven National Laboratory is summarized. Many final states such as $\eta \pi$, $\eta' \pi^{-}$, $a_{0} \pi$, $f_{1} \pi$, $a_{2} \pi$, $b_{1} \pi$, which are favored decay modes of exotics, are under investigation.
11/1995;
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N M Cason,
T Adams,
J. M. Bishop, J M LoSecco,
J J Manak,
A H Sanjari,
W D Shephard,
D. L. Stienike,
S. A. Taegar,
D. R. Thompson, [......],
D S Brown,
T. K. Pedlar,
K. K. Seth,
J. Wise,
D. Zhao,
G. S. Adams,
J. Napolitano,
M Nozar,
J. A. Smith,
M Witkowski
11/1995;
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B.B. Brabson,
R.R. Crittenden,
A.R. Dzierba,
T. Foxford,
J. Gunter,
R. Lindenbusch,
P.T. Smith,
E. Scott,
T. Sulanke,
S. Teige, [......],
T. Adams,
J.M. Bishop,
R.D. Cady,
N.M. Cason, J.M. LoSecco,
J.J. Manak,
W.D. Shephard,
D.L. Stienike,
S.A. Taegar,
D.R. Thompson
[show abstract]
[hide abstract]
ABSTRACT: Two prototype lead glass calorimeters have been constructed and tested at the AGS at Brookhaven National Lab. The first is a 25-element prototype (P1)
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
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R.R. Crittenden,
A.R. Dzierba,
J. Gunter,
R. Lindenbusch,
D.R. Rust,
E. Scott,
P.T. Smith,
T. Sulanke,
S. Teige,
B.B. Brabson, [......],
D.S. Brown,
T.K. Pedlar,
K.K. Seth,
J. Wise,
D. Zhao,
G.S. Adams,
J. Napolitano,
M. Nozar,
J.A. Smith,
M. Witkowski
[show abstract]
[hide abstract]
ABSTRACT: A 3045 element lead glass calorimeter and an associated fast trigger processor have been constructed, tested and implemented in BNL experiment E852 in conjunction with the multi-particle spectrometer (MPS). Approximately, 109 all-neutral and neutral plus charged triggers were recorded with this apparatus during data runs in 1994 and 1995. This paper reports on the construction, testing and performance of this lead glass calorimeter and the associated trigger processor.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
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Z. Bar-Yam,
J.P. Cummings,
J.P. Dowd,
P. Eugenio,
M. Hayek,
W. Kern,
E. King,
N. Shenhav,
S.U. Chung,
R.W. Hackenburg, [......],
D.S. Brown,
T. Pedlar,
K.K. Seth,
J. Wise,
D. Zhao,
G.S. Adams,
J. Napolitano,
M. Nozar,
J.A. Smith,
M. Witkowski
[show abstract]
[hide abstract]
ABSTRACT: A cylindrical multiwire drift chamber with axial charge-division has been constructed and used in experiment E852 at Brookhaven National Laboratory. It serves as a trigger element and as a tracking device for recoil protons in π p interactions. We describe the chamber's design considerations, details of its construction, electronics, and performance characteristics.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
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G.S. Adams,
T. Adams,
Z. Bar-Yam,
J.M. Bishop,
V.A. Bodyagin,
D.S. Brown,
N.M. Cason,
S.U. Chung,
J.P. Cummings,
K. Danyo, [......],
N.B. Sinev,
D.L. Stienike,
S.A. Taegar,
D.R. Thompson,
A. Tomaradze,
I.N. Vardanyan,
D.P. Weygand,
D. White,
H.J. Willutzki,
A.A. Yershov
[show abstract]
[hide abstract]
ABSTRACT: The number of pseudoscalar mesons in the mass range from 1400 to 1500 MeV/c2 has been a subject of considerable interest for many years, with several experiments having presented evidence for two closely spaced states. A new measurement of the reaction π−p→K+K−π0n has been made at a beam energy of 18 GeV. A partial wave analysis of the K+K−π0 system shows evidence for three pseudoscalar resonances, η(1295), η(1416), and η(1485), as well as two axial vectors, f1(1285), and f1(1420). Their observed masses, widths and decay properties are reported. No signal was observed for C(1480), an IGJPC=1+1−− state previously reported in φπ0 decay.
Physics Letters B.
