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Study of Hypercharge Exchange Reactions of the Type K- p --> 1- 3/2+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Aguilar-Benitez, M. ; Barreiro, F. ; Hemingway, R.J. ; et al.
Nucl.Phys.B 124 (1977) 189-228, 1977.
Inspire Record 101289 DOI 10.17182/hepdata.50024

Results are presented for the quasi two-body hypercharge exchange reactions of the type using data from a high statistics bubble chamber experiment. Total and differential cross sections and the momentum transfer dependence of the meson and hyperon resonance single density matrix elements are discussed. Amplitude analyses are performed for the first two reactions. The results are compared with quark model and duality predictions and with those from other related reactions.

20 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Evidence for Two Pseudoscalar Resonances of $\eta \pi^+ \pi^-$ System in the $D(1285)$ and $e$ / Iota Regions

Ando, A. ; Inaba, S. ; Inagaki, T. ; et al.
Phys.Rev.Lett. 57 (1986) 1296, 1986.
Inspire Record 229782 DOI 10.17182/hepdata.20226

High-statistics data on the reaction π−p→ηπ+π−n at 8.06 GeV/c were obtained. An isobarmodel partial-wave analysis was performed for the ηππ system. The η(1275) meson was confirmed as a narrow IJPC=00−+ resonance. It decays through both δπ and εη. A narrow state with IJPC=00−+ was found in an ηππ decay channel at 1.42 GeV. It has a prominent peak in a δπ decay mode. No significant E(1420) signal with IJPC=01++ was found near the mass region of 1.42 GeV.

1 data table
Table 1

No description provided.


PARITY NONCONSERVATION IN ATOMIC THALLIUM

Drell, Persis S. ; Commins, E.D. ;
Phys.Rev.Lett. 53 (1984) 968-971, 1984.
Inspire Record 208341 DOI 10.17182/hepdata.20404

We present new measurements of parity conservation in the 293-nm transition in atomic Tl81205. Linearly polarized 293-nm photons, polarization ε^, are absorbed by 6P122 atoms in crossed electric and magnetic fields. The transition probability for each Zeeman component contains a term proportional to ε^·B→ε^·E→×B→ arising from interference between the Stark E1 amplitude βE and the parity-nonconserving E1 amplitude Ep. Our result, [ImEpβ]expt=−1.73±0.33 mV/cm, is compared with estimates based on the standard electroweak model.

1 data table
Table 1

Spin of the Tl nucleus is 1/2.


Total hadronic cross-section of gamma rays in hydrogen in the energy range 0.265-GeV to 4.215-GeV

Armstrong, T.A. ; Hogg, W.R. ; Lewis, G.M. ; et al.
Phys.Rev.D 5 (1972) 1640-1652, 1972.
Inspire Record 67298 DOI 10.17182/hepdata.22462

The total cross section of γ rays in hydrogen resulting in hadron production, σT, has been measured over the energy range 265-4215 MeV. A tagging system with narrow energy bins was employed. Structure in the resonance region followed by a steady fall with energy has been observed and the results are analyzed. The forward amplitude of γ-proton scattering is evaluated, and its behavior in the Argand diagram studied as a function of energy. The relationships of the measurements to Regge-pole theory and the vector-dominance model are detailed.

2 data tables
Table 1

No description provided.

Table 2

SPIN AVERAGED FORWARD COMPTON SCATTERING AMPLITUDE. IM(AMP) WAS CALCULATED VIA THE OPTICAL THEOREM FROM A SMOOTH FIT TO THE DATA, AND USED IN THE DISPERSION RELATION TO CALCULATE RE(AMP). AT THRESHOLD THE THOMSON AMPLITUDE IS -3.0 MUB*GEV.


Measurement of the K0 Coherent Regeneration Amplitude in Cu from .6-GeV/c to 1.4-GeV/c

Birnbaum, D. ; Edelstein, R.M. ; Fisk, H.E. ; et al.
Phys.Rev.D 9 (1974) 1242, 1974.
Inspire Record 682 DOI 10.17182/hepdata.21993

The magnitude of |f21(0)|, the coherent K0 regeneration amplitude in Cu, has been measured for K momenta from 600 to 1400 MeVc. Results are compared with predictions of an optical model using forward dispersion relation predictions for real parts of kaon-nucleon scattering amplitudes.

1 data table
Table 1

No description provided.


Atomic Beam Measurement of Parity Nonconservation in Cesium

Gilbert, S.L. ; Wieman, Carl E. ;
Phys.Rev.A 34 (1986) 792-803, 1986.
Inspire Record 237319 DOI 10.17182/hepdata.26392

We present a new measurement of parity nonconservation in cesium. In this experiment, a laser excited the 6S→7S transition in an atomic beam in a region of static electric and magnetic fields. The quantity measured was the component of the transition rate arising from the interference between the parity nonconserving amplitude, scrEPNC, and the Stark amplitude, βE. Our results are ImscrEPNC/β=−1.65±0.13 mV/cm and C2p=-2±2, where C2p is the proton-axial-vector–electron-vector neutral-current coupling constant. These results are in agreement with previous less precise measurements in cesium and with the predictions of the electroweak standard model. We give a detailed discussion of the experiment with particular emphasis on the treatment and elimination of systematic errors. This experimental technique will allow future measurements of significantly higher precision.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).


NEW OBSERVATION OF A PARITY VIOLATION IN CESIUM

Bouchiat, M.A. ; Guena, J. ; Pottier, L. ; et al.
Phys.Lett.B 134 (1984) 463-468, 1984.
Inspire Record 200186 DOI 10.17182/hepdata.30610

The parity violation induced by weak neutral currents is measured in a ΔF =1 hyperfine component of the 6S–7S transition of the Cs atom. The measured value ( Im E PV 1 β ) = −1.78 ± 0.26 (statistical rms deviation) ±0.12 (systematic uncertainty) mV/cm, agrees with our previous measurement in a ΔF =0 component, and constitutes an important cross-check. Our result excludes a parity violation induced by a purely axial hadronic neutral current.

1 data table
Table 1

(7s)2S1/2:F=3 --> (6s)2S1/2:F=4 transition.


A study of the hypercharge exchange reactions k- p ---> 1- 1/2+ at an incoming momentum of 4.25 gev/c

De Groot, A.J. ; Hodgland, W. ; Jongejans, B. ; et al.
Nucl.Phys.B 74 (1974) 77-101, 1974.
Inspire Record 94650 DOI 10.17182/hepdata.32272

Results are reported of a study of the hypercharge reactions K − p → ωΛ (la), K − p → φΛ (lb), K − p → φ ∑ o (lc), K − p → ϱ o Λ (ld), K − p → ϱ o ∑ o (le), K − p → ϱ − ∑ + (lf) in a 12 events/ub bubble chamber experiment using K − mesons of 4.25 GeV/ c momentum. Total and differential cross sections are presented as well as the density matrix elements of the peripherally produced vector meson and (except for reaction (1f)) the hyperon polarization. For reactions (1a) and (1b) an amplitude analysis is performed. The mass and the width of the ϱ−, φ− and f-meson have been determined.

4 data tables
Table 1

FURTHER DATA FROM THIS COLLABORATION ON THESE REACTIONS WITH TEN TIMES BETTER STATISTICS ARE PRESENTED IN M. J. LOSTY ET AL., NP B133, 38 (1978).

Table 2

No description provided.

Table 3

No description provided.

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PRODUCTION AND DECAY ANGULAR DISTRIBUTIONS OF THE Y* (1385) IN THE LINE REVERSED REACTIONS: pi+ p ---> K+ Y* (1385) AND K- p ---> pi- Y* (1385) AT 11.5-GeV/c

Cautis, C.V. ; Ballam, Joseph ; Bouchez, J. ; et al.
Nucl.Phys.B 156 (1979) 507-531, 1979.
Inspire Record 133382 DOI 10.17182/hepdata.34679

We have measured in a single experimental setup, the differential cross sections and decay angular distributions of the Y ∗ (1385) produced in the two line-reversed reactions: π + p → K + Y ∗+ (1385) (279 events/ω b ) and K − p → π − Y ∗+ (1385) (190 events/ωb) at 11.5 GeV/ c . The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find the differential cross sections and Y ∗ polarizations for the two reactions to be in agreement with exchange-degeneracy predictions, if kinematic differences are taken into account. The Stodolsky-Sakurai and additive quark model predictions are in agreement with the main features of the decay angular distributions of the Y ∗ (1385), except for small violations at low momentum transfer, which can be associated with a finite helicity non-flip contribution in the forward direction.

6 data tables
Table 1

Axis error includes +- 10/10 contribution.

Table 2

THESE FINAL DIFFERENTIAL CROSS SECTIONS ARE INCLUDED IN THE RECORD OF J. BALLAM ET AL., PRL 41, 676 (1978).

Table 3

TRANSVERSITY AMPLITUDES FOR SIG(1385P13)+ PRODUCTION. THE IMAGINARY PARTS OF T(11) AND T(-1-1) WERE ARBITRARILY FIXED AT ZERO.

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K0(L) K0(S) TRANSMISSION REGENERATION ON DEUTERONS AND NEUTRONS IN A MOMENTUM RANGE OF 10-GEV/C - 50-GEV/C

The BERLIN-BUDAPEST-DUBNA-PRAGUE-SERPUKHOV-SOFIYA-TBILISI collaboration Albrecht, K.-F. ; Birulev, V.K. ; Genchev, V. ; et al.
Nucl.Phys.B 158 (1979) 29-38, 1979.
Inspire Record 145094 DOI 10.17182/hepdata.34627

The energy dependence of the K L 0 -K S 0 transmission regeneration amplitudes on deuterons and neutrons in the momentum region 10–50 GeV/ c is determined. The moduli of the modified transmission amplitudes are momentum dependent. These dependences are fitted by the expression A j p − nj , where A j and n j ( j = d, n) are constants: A d =2.88 ±0.04 mb , n d =0.546±0.030, for deuterons , A n =1.97 ±0.14 mb , n n =0.530±0.019, for neutrons , The amplitude phases do not depend on the kaon momentum and are equal to ϕ d = (−130.9 ± 2.7)° ϕ n = (−132.3 ± 1.7)°. The mean value of the ratio of the total cross-section differences for K 0 and K 0 interactions with neutrons and protons is determined. The residues of the partial ω and ϱ amplitudes, which contribute to the kaon-nucleon interaction amplitudes, are also obtained.

2 data tables
Table 1

FORWARD CROSS SECTION, AMPLITUDE AND PHASE FOR K0 REGENERATION.

Table 2

(AK0 - K0) TOTAL CROSS SECTION DIFFERENCES.