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Measurement of CP violating asymmetries in B0 decays to CP eigenstates

The BaBar collaboration Aubert, Bernard ; Boutigny, D. ; De Bonis, I. ; et al.

Phys.Rev.Lett. 86 (2001) 2515-2522, 2001.

Inspire Record 553002 DOI 10.17182/hepdata.50471

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23 million Upsilon(4S)-->B-anti-B decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events where one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta=0.34 +/- 0.20 (stat) +/- 0.05 (syst).

1 data table

Table 1

Standard Model predicts the time-dependent rate asymmetry as follows: A(t) = (B0(t)-BBAR0(t))/(B0(t)+BBAR0(t)) = SIN(2*BETA)*SIN(Delta(M)*t), where Delta(M) is the mass difference between the two B0 mass eigenstates. The total systematic error equals +0.50 -0.46.

Elliptic flow in Au + Au collisions at s(N N)**(1/2) = 130-GeV.

The STAR collaboration Ackermann, K.H. ; Adams, N. ; Adler, C. ; et al.

Phys.Rev.Lett. 86 (2001) 402-407, 2001.

Inspire Record 533414 DOI 10.17182/hepdata.93232

Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au+Au collisions at sqrt(s_NN)=130 GeV using the STAR TPC at RHIC. The elliptic flow signal, v_2, averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic flow are also presented.

2 data tables

Table 1

Elliptic flow as a function of centrality defined as nch/nmax. Also given is epsilon, the initial space eccentricity of the overlap region, as well as the cumulative fraction of events starting with the most central. From the results of the study of non-flow contributions by different subevent selections and the maximum magnitudes of the first and higher-order harmonics, we estimate a systematic error for v2 of about 0.007, with somewhat smaller uncertainty for the mid-centralities where the resolution of the event plane is high.

Table 2

Elliptic flow as a function of transverse momen-tum for minimum bias events

Search for CP violation in D0 and D+ decays.

The FOCUS collaboration Link, J.M. ; Paolone, V.S. ; Reyes, M. ; et al.

Phys.Lett.B 491 (2000) 232-239, 2000.

Inspire Record 527840 DOI 10.17182/hepdata.42984

A high statistics sample of photoproduced charm particles from the FOCUS (E831) experiment at Fermilab has been used to search for CP violation in the Cabibbo suppressed decay modes D+ to K-K+pi+, D0 to K-K+ and D0 to pi-pi+. We have measured the following CP asymmetry parameters: A_CP(K-K+pi+) = +0.006 +/- 0.011 +/- 0.005, A_CP(K-K+) = -0.001 +/- 0.022 +/- 0.015 and A_CP(pi-pi+) = +0.048 +/- 0.039 +/- 0.025 where the first error is statistical and the second error is systematic. These asymmetries are consistent with zero with smaller errors than previous measurements.

3 data tables

Table 1

All N-values corrected by efficiencies obtained from Monte-Carlo simulations. The CP asymmetry can be written as: ACP=(eta(D)-eta(DBAR))/(eta(D)+eta(DBAR)), where eta(Q=D+ KK)=(N(Q=D+ KK)/N(Q=D+ K) - N(Q=D- KK)/N(Q=D- K))/(N(Q=D+ KK)/N(Q=D+ K) + N(Q=D- KK)/N(Q=D- K)).

Table 2

All N-values corrected by efficiencies obtained from Monte-Carlo simulations. The CP asymmetry can be written as: ACP=(eta(D)-eta(DBAR))/(eta(D)+eta(DBAR)), where eta(Q=D0 KK)=(N(Q=D0 KK)/N(Q=D0 K) - N(Q=DBAR0 KK)/N(Q=DBAR0 K))/(N(Q=D0 KK)/N(Q=D0 K) + N(Q=DBAR0 KK)/N(Q=DBAR0 K)).

Table 3

All N-values corrected by efficiencies obtained from Monte-Carlo simulations. The CP asymmetry can be written as: ACP=(eta(D)-eta(DBAR))/(eta(D)+eta(DBAR)), where eta(Q=D0 PIPI)=(N(Q=D0 PIPI) - N(Q=DBAR0 PIPI))/(N(Q=D0 PIPI) + N(Q=DBAR0 PIPI)).

The compact emulsion spectrometer.

Buontempo, S. ; Camilleri, L. ; Catanesi, M.G. ; et al.

Nucl.Instrum.Meth.A 457 (2001) 464-470, 2001.

Inspire Record 531752 DOI 10.17182/hepdata.49938

An emulsion spectrometer has been built and tested with pion beams in a 0.7 T magnetic field. A momentum resolution, Δ P / P =13%±1%, has been obtained for 5 and 10 GeV /c particles.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

A measurement of the transverse polarization of Lambda-hyperons produced in n C reactions in the EXCHARM experiment.

The EXCHARM collaboration Aleev, A.N. ; Balandin, V.P. ; Dvalishvili, E.A. ; et al.

Eur.Phys.J.C 13 (2000) 427-432, 2000.

Inspire Record 509253 DOI 10.17182/hepdata.43333

New precise data of the$\Lambda^0$polarization are obtained in the EXCHARM experiment at the Serpukhov accelerator. The$\Lambda^0$

2 data tables

Table 1

LAMBDA polarization as a function of PT for the whole XL region.

Table 2

LAMBDA polarization as a function of PT for three XL regions.

Tensor analyzing powers in the reactions p(d,p)d and p(d,p)p n at zero angle for incident-deuteron momenta between 3.5-GeV/c and 6.5-GeV/c.

Azhgirei, L.S. ; Chernykh, E.V. ; Ladygin, V.P. ; et al.

Phys.Atom.Nucl. 61 (1998) 432-447, 1998.

Inspire Record 474393 DOI 10.17182/hepdata.17151

None

12 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Tensor analyzing power T(20) in backward elastic d p scattering and breakup at 0-degrees between 3.5-GeV/c and 6.5-GeV/c

Azhgirey, L.S. ; Chernykh, E.V. ; Kobushkin, A.P. ; et al.

Phys.Lett.B 391 (1997) 22-28, 1997.

Inspire Record 456818 DOI 10.17182/hepdata.28323

The tensor analyzing power T 20 for the p ( d , p d) and p ( d , p ) pn reactions θ cm p = 180° have been measured at incident deuteron momenta from 3.5 to 6.5 GeV/ c . For both reactions T 20 remains negative up to internal momentum k ⋍ 0.85 GeV/ c and show a rich structure beyond the region where T 20 is expected to be determined by the S - and D -states of the deuteron. The T 20 data for deuteron breakup without pion production, close to the backward elastic kinematics, were obtained simultaneously with the elastic data.

1 data table

Table 1

K is the internal momentum of the nucleon.

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

Table 1

No description provided.

Table 2

No description provided.