Meshchanin, A.P.
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MEASUREMENT OF POLARIZATION IN THE pi- p ---> pi0, n, pi0 ---> 2 gamma REACTION AT 40-GeV/c WITH THE REGISTRATION OF ALL REACTION PRODUCTS

Borisov, N.S. ; Kazarinov, Yu.M. ; Liburg, M.Yu. ; et al.
JINR-P1-84-311, 1984.
Inspire Record 203007 DOI 10.17182/hepdata.9904

None

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


OBSERVATION OF THE ASYMMETRY IN THE REACTION pi- polarized p ---> omega n AT 40-GeV/c

Vasiliev, A.N. ; Matulenko, Yu.A. ; Meshchanin, A.P. ; et al.
44-51, 1984.
Inspire Record 206927 DOI 10.17182/hepdata.10530

None

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


MEASUREMENT OF ASYMMETRY IN THE REACTION pi- polarized p ---> K0 LAMBDA AT 40-GeV/c

Vasiliev, A.N. ; Matulenko, Yu.A. ; Meshchanin, A.P. ; et al.
52-59, 1984.
Inspire Record 206928 DOI 10.17182/hepdata.10569

None

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


Polarization in the Reaction $\pi^-$ Polarized $p \to \pi^0 n$ at 40-{GeV}/$c$

Avvakumov, I.A. ; Apokin, V.D. ; Bagaturiya, Yu.Sh. ; et al.
Nucl.Phys.B 255 (1985) 253-272, 1985.
Inspire Record 206940 DOI 10.17182/hepdata.33791

The paper presents results on measuring the polarization in the reaction π − p→ π 0 n at 40 GeV/ c in the 4-momentum transfer range 0<| t |⩽2 (GeV/ c ) 2 . The results based on the statistics of about 2.2 million recorded events made it possible to observe a noticeable value and complex structure in the polarization behaviour up to | t |⩽2 (GeV/ c ) 2 .

2 data tables match query

POLARIZATION ASYMMETRY OSCILLATIONS IN REACTION pi- p ---> p0 n AT t <= 3-GeV/c**2

Apokin, V.D. ; Arestov, Yu.I. ; Belikov, N.I. ; et al.
Sov.J.Nucl.Phys. 45 (1987) 840, 1987.
Inspire Record 234598 DOI 10.17182/hepdata.40905

None

1 data table match query
Table 1

No description provided.


THE OBSERVATION OF THE ASYMMETRY IN THE REACTION pi- polarized p ---> pi0 X AT THE ANGLE 90-degrees IN cms AT 40-GeV/c

Vasiliev, A.N. ; Matulenko, Yu.A. ; Meshchanin, A.P. ; et al.
60-66, 1984.
Inspire Record 206936 DOI 10.17182/hepdata.40968

None

1 data table match query
Table 1

No description provided.


Measurement of the angular distribution of electrons from W ---> e neutrino decays observed in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.D 63 (2001) 072001, 2001.
Inspire Record 533572 DOI 10.17182/hepdata.41717

We present the first measurement of the electron angular distribution parameter alpha_2 in W to e nu events produced in proton-antiproton collisions as a function of the W boson transverse momentum. Our analysis is based on data collected using the D0 detector during the 1994--1995 Fermilab Tevatron run. We compare our results with next-to-leading order perturbative QCD, which predicts an angular distribution of (1 +/- alpha_1 cos theta* + alpha_2 cos^2 theta*), where theta* is the polar angle of the electron in the Collins-Soper frame. In the presence of QCD corrections, the parameters alpha_1 and alpha_2 become functions of p_T^W, the W boson transverse momentum. This measurement provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W boson mass measurement.

1 data table match query
Table 1

Angular distributions of the emitted charged lepton is fitted to the formula d(sig)/d(pt**2)/dy/d(cos(theta*)) = const*(1 +- alpha_1*cos(theta*) + alpha_2*(cos(theta*))**2). The angle theta* is measured in the Collins-Soper frame. alpha_1 velues are calculated based on the measured PT(W) of each event. Possible variations of alpha_1 are treated as a source of systematic uncertainty.


Measurement of A(c) with charmed mesons at SLD.

The SLD collaboration Abe, Kenji ; Abe, Koya ; Abe, Toshinori ; et al.
Phys.Rev.D 63 (2001) 032005, 2001.
Inspire Record 533573 DOI 10.17182/hepdata.41721

We present a direct measurement of the parity-violation parameter $A_c$ in the coupling of the $Z^0$ to $c$-quarks with the SLD detector. The measurement is based on a sample of 530k hadronic $Z^0$ decays, produced with a mean electron-beam polarization of $|P_e| = 73 %$. The tagging of $c$-quark events is performed using two methods: the exclusive reconstruction of $D^{\ast+}$, $D^+$, and $D^0$ mesons, and the soft-pions ($\pi_s$) produced in the decay of $D^{\ast+}\to D^0 \pi_s^+$. The large background from $D$ mesons produced in $B$ hadron decays is separated efficiently from the signal using precision vertex information. The combination of these two methods yields $A_c = 0.688 \pm 0.041.$

1 data table match query
Table 1

CONST(NAME=A_C) is connected with the forward-backward asymmetry by following way: ASYM(NAME=FB) = ABS(P_e)*CONST(NAME=A_C)*2z/(1 + z**2), where z = cos(theta), theta is the polar angle of the outgoing fermion relative to the incident electron, P_e is the longitudinal polarization of the electron beam. Two values for constant A_c were obtained using two different c-quark tagging methods: exclusive charmed-meson reconstruction (C=EXCLUSIVE) and inclusive soft-pion analysis (C=SOFT_PIONS).


Measurement of the left-right forward - backward asymmetry for charm quarks with D*+ and D+ mesons

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.Lett. 75 (1995) 3609-3613, 1995.
Inspire Record 404272 DOI 10.17182/hepdata.19646

We present a direct measurement of Ac=2vcac(vc2+ac2) from the left-right forward-backward asymmetry of D*+ and D+ mesons in Z0 events produced with the longitudinally polarized SLAC Linear Collider beam. These Z0→cc¯ events are tagged on the basis of event kinematics and decay topology from a sample of hadronic Z0 decays recorded by the SLAC Large Detector. We measure Ac0=0.73±0.22(stat)±0.10(syst).

1 data table match query
Table 1

No description provided.


Spin correlation in t anti-t production from p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 256-261, 2000.
Inspire Record 524260 DOI 10.17182/hepdata.42996

The D0 collaboration has performed a study of spin correlation in tt-bar production for the process tt-bar to bb-bar W^+W^-, where the W bosons decay to e-nu or mu-nu. A sample of six events was collected during an exposure of the D0 detector to an integrated luminosity of approximately 125 pb^-1 of sqrt{s}=1.8 TeV pp-bar collisions. The standard model (SM) predicts that the short lifetime of the top quark ensures the transmission of any spin information at production to the tt-bar decay products. The degree of spin correlation is characterized by a correlation coefficient k. We find that k>-0.25 at the 68% confidence level, in agreement with the SM prediction of k=0.88.

1 data table match query
Table 1

No description provided.