Exclusive
Max results
Sort by Reverse order

Showing 10 of 4206 results

Measurements of B ---> D(s)+ X decays

The CLEO collaboration Gibaut, D. ; Kinoshita, K. ; Pomianowski, P. ; et al.
Phys.Rev.D 53 (1996) 4734-4746, 1996.
Inspire Record 401599 DOI 10.17182/hepdata.47241

This paper describes new measurements from CLEO of the inclusive B→Ds+X branching fraction as well as the B+→Ds(*)+D¯(*)0 and B0→Ds(*)+D(*)− branching fractions. The inclusive branching fraction is B(B→Ds+X)=(12.11±0.39±0.88±1.38)% where the first error is statistical, the second is the systematic error, and the third is the error due to the uncertainty in the Ds+→φπ+ branching fraction. The branching fractions for the B→Ds(*)+D¯(*) modes are found to be between 0.9% and 2.4% and are significantly more precise than previous measurements. The sum of the B→Ds(*)+D¯(*) branching fractions is consistent with the results of fits to the inclusive Ds+ momentum spectrum. Factorization is used to arrive at a value for fDs, the Ds+ decay constant. © 1996 The American Physical Society.

1 data table
Table 1

FORMFACTOR(NAME=FP,C=DECAY CONSTANT) is pseudoscalar meson decay constant. Three different methods are used: 1) C=MUNU: D/S+ --> MU+ NUMU, 2) C = ENU: B --> D/S+ D*BAR / B --> D*BAR E+ NU, and 3) C = PI : B --> D/S+ D*BAR / B0 - -> PI+(RHO+) D*BAR-. The F(D/S) is evaluated from B decay assuming the factorization.


Strangelet search and antinuclei production studies in Pb + Pb collisions

The NA52 (NEWMASS) collaboration Ambrosini, G. ; Appelquist, G. ; Arsenescu, R. ; et al.
Nucl.Phys.A 610 (1996) 306C-316C, 1996.
Inspire Record 432734 DOI 10.17182/hepdata.36512

We searched for long-lived strange quark matter particles, so-called strangelets , and studied particle and antiparticle production in Pb + Pb collisions at 158 GeV/ c per nucleon at zero degree production angle. We give upper limits for the production of strangelets covering a mass to charge ratio up to 120 GeV/ c 2 and lifetimes t lab > 1.2 μ s and plot invariant differential production cross sections as a function of rapidity for a variety of particles.

1 data table
Table 1

No description provided.


Anomalous J / psi suppression in Pb + Pb collisions at 158-A-GeV/c

The NA50 collaboration Gonin, Michel ; Abreu, M.C. ; Alexa, C. ; et al.
Nucl.Phys.A 610 (1996) 404C-417C, 1996.
Inspire Record 432728 DOI 10.17182/hepdata.36494

Cross sections for J ψ,ψ′ and Drell-Yan production in Pb+Pb collisions at 158×A GeV/c are presented and compared with results obtained by the NA38 and NA51 collaborations. The Pb+Pb data have been collected by the NA50 collaboration using the NA38 dimuon spectrometer. The Drell-Yan mechanism is found to scale as (A projectile · B target ) in p+B target and A projectile + B target collisions including Pb+Pb collisions. Regarding J ψ , an anomalous suppression is observed in Pb+Pb collisions with respect to the suppression observed in p+B target , O+B target and S+U collisions. The cross section ratios ψ′ ( J ψ ) are similar in Pb+Pb and S+U collisions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Production of the g(1640) Meson in pi p Interactions at 6 GeV/c

Crennell, D.J. ; Karshon, U. ; Lai, K.W. ; et al.
Phys.Lett.B 28 (1968) 136-139, 1968.
Inspire Record 54727 DOI 10.17182/hepdata.29107

We present the results of a spin determination of the g 1 − (1640) meson from an analysis of its dipion decay mode (π − π 0 ), and find that spin three (or maybe greater) is favored [1,2]. We also report on the observation of an isospin one KK̄ enhancement at 1640 MeV which is consistent with a new decay mode of the g meson. A relative branching ratio of (K K ̄ /ππ) = 8 ± 3 8 % is obtain from our analysis.

2 data tables
Table 1

The values of the cross sections were presented for reactions with KS finalstates for visible KS decays only.

Table 2

The cross section value is corrected for invisible KS decay.


Electroproduction of pions near the $\Delta(1236)$ isobar and the form-factor $G^*_M(q^2)$ of the $({\gamma} N\Delta)$ vertex

Bartel, W. ; Dudelzak, B. ; Krehbiel, H. ; et al.
Phys.Lett.B 28 (1968) 148-151, 1968.
Inspire Record 52791 DOI 10.17182/hepdata.45279

The cross section for inelastic electron-proton scattering was measured at incident electron energies of 1.5 to 6 GeV by magnetic analysis of the scattered electrons at angles between 10° and 35°. For invariant masses of the hardonic final state W ⩽ 1.4 GeV. the measured spectra are compared with theoretical predictions for electroproduction of the Δ(1236) isobar. The magnetic dipole transition form factor G ∗ M ( q 2 ) of the (γ N Δ)-vertex is derived for momentum transfers q 2 = 0.2 − 2.34 (GeV/ c ) 2 ard found to decrease more rapidly with q 2 than the proton form factors.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution.


The production of nucleon resonances in proton proton collisions at high energy and large momentum transfers

Allaby, J.V. ; Binon, F. ; Diddens, A.N. ; et al.
Phys.Lett.B 28 (1968) 229-232, 1968.
Inspire Record 56834 DOI 10.17182/hepdata.29196

Experimental results are presented on the excitation of the nucleon isobars N ∗ (1518) and N ∗ (1688) in proton-proton collisions at an incident momentum of 19.2 GeV/ c and in the range of four-momentum squared 0.6 ⩽7 z . sfnc ; t | ⩽ 5.8 GeV 2 .

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).


AN INVESTIGATION OF THE 1.4-GeV/c**2 NUCLEON ISOBAR IN PROTON PROTON INTERACTIONS

Tan, T.H. ; Perl, Martin L. ; Martin, F. ; et al.
Phys.Lett.B 28 (1968) 195-198, 1968.
Inspire Record 52678 DOI 10.17182/hepdata.29198

The production of N ∗ (1400) isobar in the reaction pp → pN ∗+ (1400), where N ∗ (1400) → n π + and p π 0 , is investigated with the aid of one-pion exchange model. The one-pion exchange mechanism does not seem to dominate the production process. The isospin of N ∗ (1400) is found to be I = 1 2 , and the elasticity of the resonance is estimated to be 0.66.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (?////Due to fitting mass spectrum).


A study of the reaction pi-minus + p ---> lambda + anti-lambda + n at 7 and 12 gev/c

Beusch, W. ; Fischer, W.E. ; Pepin, M. ; et al.
Phys.Lett.B 28 (1968) 211-214, 1968.
Inspire Record 56830 DOI 10.17182/hepdata.29078

Over 100 unambiguous π − + p → Λ + Λ + n events have been observed in a magnet spark chamber. The data provide good evidence for peripheral production of Λ Λ and n Λ (via meson exchange) and against peripheral n Λ (double baryon exchange). No resonances in the Λ Λ system are observed. Angular distributions and Λ( Λ ) polarizations are analysed.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (?////Corrected for neutral decays, absorption).


Study of the muon pair production at center-of-mass energies from 20-GeV to 136-GeV with the ALEPH detector

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Lett.B 399 (1997) 329-341, 1997.
Inspire Record 440218 DOI 10.17182/hepdata.47490

The total cross section and the forward-backward asymmetry for the process e + e − → μ + μ − ( nγ ) are measured in the energy range 20–136 GeV by reconstructing the effective centre-of-mass energy after initial state radiation. The analysis is based on the data recorded with the ALEPH detector at LEP between 1990 and 1995, corresponding to a total integrated luminosity of 143.5 pb −1 . Two different approaches are used: in the first one an exclusive selection of events with hard initial state radiation in the energy range 20–88 GeV is directly compared with the Standard Model predictions showing good agreement. In the second one, all events are used to obtain a precise measurement of the energy dependence of σ 0 and A FB 0 from a model independent fit, enabling constraints to be placed on models with extra Z bosons.

2 data tables
Table 1

Exlclusive analysis from events with hard ISR.

Table 2

Inclusive analysis from evvents with no specific selection of hard ISR.


Pion absorption on He-3 and He-4 with emission of three energetic protons.

The LADS collaboration Lehmann, A. ; Androic, D. ; Backenstoss, G. ; et al.
Phys.Rev.C 55 (1997) 2931-2950, 1997.
Inspire Record 440453 DOI 10.17182/hepdata.25724

Results from a 4π solid angle measurement of the reactions 3He(π+,ppp) and 4He(π+,ppp)n at incident pion energies of Tπ+=70, 118, 162, 239, and 330 MeV are presented. For 3He the total absorption cross sections and their decomposition into two-proton and three-proton components are evaluated; for 4He the three-proton absorption cross sections are given. The differential distributions of the three-proton multinucleon absorption mode of both nuclei are analyzed and compared to each other by making use of a complete set of variables. The data are investigated for signatures of initial and final state interactions: it is found that more than half of the three-proton yield cannot be accounted for by cascade mechanisms. The remaining strength shows dependence on the incident pion angular momentum, but also structures that are not explained by simple semiclassical models.

3 data tables
Table 1

Absorption cross section. Total errors are presented.

Table 2

First and second errors are due to fits and normalization uncertainties, respectively.

Table 3

First and second errors are due to fits and normalization uncertainties, respectively.