Date

Production of neutron rich isotopes from the fragmentation of Si-28 projectiles at p(lab) = 14.6-GeV/c per nucleon

The E814 collaboration Barrette, J. ; Bellwied, R. ; Braun-Munzinger, P. ; et al.
Phys.Rev.C 52 (1995) 956-963, 1995.
Inspire Record 406590 DOI 10.17182/hepdata.25860

An investigation of the production of neutron-rich isotopes from the fragmentation of Si28 projectiles at plab=14.6 GeV/c per nucleon was performed using the BNL-AGS-E814 spectrometer. We have measured the inclusive production cross sections of neutron-rich fragments (6He, He8, Li8, Li9, Be10, Be11, and B13). We have also measured the transverse momentum distributions for He6 and Li9, and the forward and transverse energy distributions associated with He6 production. The momentum distributions were analyzed in the context of the Goldhaber model. The question of whether the fragments are produced in the decay of the projectile following its electromagnetic excitation was also investigated.

1 data table

No description provided.


E decay to eta pi pi in anti-p p annihilation at rest

The Crystal Barrel collaboration Amsler, C. ; Armstrong, D.S. ; Baker, C.A. ; et al.
Phys.Lett.B 358 (1995) 389-398, 1995.
Inspire Record 407517 DOI 10.17182/hepdata.28511

We have observed the ηπ + π − and ηπ 0 π 0 decay modes of the E meson in p p annihilation at rest into π + π − π 0 π 0 η . The mass and width of the E meson are 1409 ± 3 and 86 ± 10 MeV. The production and decay branching ratio is B( p p → Eππ)B(E → ηππ) = (3.3 ± 1.0) × 10 −3 . With a spin-parity analysis we determine that J P = 0 − . The observation of the ηπ 0 π 0 decay mode establishes that E is isoscalar ( C = +1). We find that E decays to η ( ππ ) s (where ( ππ ) s is an S-wave dipion) and πa 0 (980)(→ πη ) with a relative branching ratio of (78 ± 16) %. Using the K K π production and decay branching ratio measured earlier we determine that B[E → K K π] B[E → ηππ] = 0.61 ± 0.19 . A comparison with observations in radiative J Ψ decays suggests that E and ι η (1416) are identical.

1 data table

Unobserved channels (E --> ETA 2PI0)2PI0 and (E --> ETA PI+ PI-)PI+PI- was taken into account.


Search for pion neutron bound states in 14.6-A/GeV Si + nucleus collisions

The E814 collaboration Barrette, J. ; Bellwied, R. ; Braun-Munzinger, P. ; et al.
Phys.Rev.C 52 (1995) 2679-2683, 1995.
Inspire Record 407608 DOI 10.17182/hepdata.25875

We have conducted a search for bound states of a negative pion and a number of neutrons (pineuts) using the E814 spectrometer. A beam of Si28 at a momentum of 14.6A GeV/c was used to bombard targets of Al, Cu, Sn, and Pb. We describe our experimental technique, present measured upper limits for pineut production, and discuss the significance of our results.

1 data table

AUTHORS NAMED CHARGED- BY PINEUT. Here ALL means the total number of interactions.


Observation of radiative anti-p p annihilation into a phi meson

The Crystal Barrel collaboration Amsler, C. ; Armstrong, D.S. ; Augustin, I. ; et al.
Phys.Lett.B 346 (1995) 363-370, 1995.
Inspire Record 401140 DOI 10.17182/hepdata.28709

The annihilation p p → Φγ has been investigated with the Crystal Barrel detector at LEAR for antiprotons stopped in liquid hydrogen. The observed branching ratio BR ( p p → Φγ = (1.7 ± 0.4) · 10 −5 is almost two orders of magnitude higher than expected from the OZI-rule. As a by-product, the branching ratios BR ( p p → K L K S ) = (9.0 ± 0.6) · 10 −4 and BR ( p p → Φπ 0 ) = (5.5 ± 0.7) · 10 −4 have been measured.

1 data table

No description provided.


First observation of the production of nucleon resonances in anti-proton annihilation in liquid deuterium

The Crystal Barrel collaboration Amsler, C. ; Armstrong, D.S. ; Augustin, I. ; et al.
Phys.Lett.B 352 (1995) 187-192, 1995.
Inspire Record 405540 DOI 10.17182/hepdata.28705

None

1 data table

No description provided.


One-spin pion asymmetry in the d(pol.) + A --> pi+- + X processes near Theta(pi) = 90-degrees.

Averichev, G.S. ; Agakishiev, G. ; Asanova, M.E. ; et al.
Dubna JINR - 1(69)-95 (95/04,rec.Jul.) 27-36, 1995.
Inspire Record 404986 DOI 10.17182/hepdata.70491

None

1 data table

No description provided.


Measurement of the Form Factors for the Decay $D_s^+ \to \phi \mu^+ \nu$

The E687 collaboration Frabetti, P.L. ; Cheung, H.W.K. ; Cumalat, John P. ; et al.
Phys.Lett.B 328 (1994) 187-192, 1994.
Inspire Record 372405 DOI 10.17182/hepdata.42502

The fermilab high-energy photoproduction experiment E687 provides a sample of approximately 90 events of the decay mode D + s → φμ + ν . The ratios of the form factors governing the decay are measured to be R v =1.8±0.9±0.2 and R 2 = 1.1±0.8±0.1, implying a polarization of Г 1 /Г t = 1.0±0.5±0.1 for the electron decay, consistent with our measurement of the form factor for the decay D + → K ∗0 μ + ν .

1 data table

With a vetor meson in the final state, there are four formfactors, V(Q2), A1(Q2), A2(Q2), A3(Q2). Charge conjugated states are understood.


Search for N (phi) (1960) baryon

The SPHINX collaboration Balats, M.Ya. ; Belyaev, I.M. ; Dorofeev, V.A. ; et al.
Z.Phys.C 61 (1994) 399-405, 1994.
Inspire Record 376444 DOI 10.17182/hepdata.14371

In the experiments at the SPHINX facility in the 70 GeV proton beam of the IHEP accelerator the diffractive production reactionsp+N→[Σ(1385)0K+] +N andp+N→[Σ(1385)0K+]+N+ (neutral particles) were studied. In the effective mass spectra of the [Σ(1385)0K+] system in these processes there were no signals from the anomalously narrow baryon stateNϕ (1960) which had been observed earlier in the measurement at the BIS-2 setup.

2 data tables

No description provided.

No description provided.


Centrality dependence of longitudinal and transverse baryon distributions in ultrarelativistic nuclear collisions

The E814 collaboration Barrette, J. ; Bellwied, R. ; Braun-Munzinger, P. ; et al.
Phys.Rev.C 50 (1994) 3047-3059, 1994.
Inspire Record 385496 DOI 10.17182/hepdata.25982

Inclusive double differential multiplicities d2N/dy dpt and related quantities have been measured for protons and deuterons produced in 14.6A GeV/c Si+Al and Si+Pb collisions using the E814 forward spectrometer at the AGS at BNL. Collision ‘‘centrality’’ is determined by measuring Nc, the total charged particle multiplicity in the pseudorapidity range 0.85<η<3.8. For both systems Si + Al and Si + Pb, an increase in the proton rapidity distribution dN/dy at midrapidity and a corresponding decrease at higher rapidities are observed with increasing Nc. For Si+Pb, Boltzmann slope parameters TB increase significantly in the most central collisions. The measured distributions exhibit a centrality dependence even when σ/σgeo≲10%, where full overlap between the Si and Pb nuclei occurs in a simple geometric picture. The proton rapidity distribution dN/dy is presented for the symmetric system Si+Al over the entire rapididty interval. The total number of protons, which is the integral of this quantity over rapidity, varies with Nc. Results are compared with various model calculations, mostly using the hadronic cascade codes ARC and RQMD. No significant nuclear transparency is observed, indicating that large baryon and energy densities are produced in these collisions.

1 data table

No description provided.


The Search for heavy pentaquark exotic baryons with hidden strangeness in the p + N ---> (p Phi) + N and p + N ---> (Lambda (1520) K+) + N reactions at E(p) = 70-GeV

The SPHINX collaboration Dorofeev, V.A. ; Golovkin, S.V. ; Kozhevnikov, A.P. ; et al.
Phys.Atom.Nucl. 57 (1994) 227-237, 1994.
Inspire Record 385732 DOI 10.17182/hepdata.40688

None

2 data tables

No description provided.

The upper limits for production of EXOTIC-NUCLEON with narrow width (<50 MeV). Linear A-dependence of the cross section is assumed.