Observation of polarization effects in Lambda(c)+ semileptonic decay

Polarization of the Λ daughter baryon from Λ c + → Λl + v l decay has been measured for the first time using the ARGUS detector at the DORIS II ϵ + ϵ − storage ring. Expressed in terms of the Λ c + semileptonic asymmetry parameter the result is α Λc = −0.91±0.49 for events in the mass region 1.85< M ( Λl + )<2.20 GeV/ c 2 .

electron positron: colliding beams
colliding beams: electron positron
electron positron: annihilation
annihilation: electron positron
asymmetry
Lambda: polarization
polarization: Lambda
angular distribution
ARGUS
experimental results

References(15)

Figures(0)

Observations of Lambda(charm)+ semileptonic decay

ARGUS

Collaboration

•

H. Albrecht
(
- DESY
)

et al.

- Phys.Lett.B 269 (1991) 234-242
•
DOI:
- 10.1016/0370-2693(91)91480-J

Observation of xi(c)0 semileptonic decay

ARGUS

Collaboration

•

H. Albrecht
(
- DESY
)

et al.

- Phys.Lett.B 303 (1993) 368-376
•
DOI:
- 10.1016/0370-2693(93)91447-U

Polarization effects in exclusive semileptonic Lambda(c) and Lambda(b) charm and bottom baryon decays

J.G. Korner
(
- Mainz U., Inst. Phys. and
- DESY
)
,
M. Kramer
(
- Mainz U., Inst. Phys. and
- DESY
)

- Phys.Lett.B 275 (1992) 495-505
•
DOI:
- 10.1016/0370-2693(92)91623-H

1/m(c) terms in Lambda(c)+ semileptonic decays

Winston Roberts
(
- Old Dominion U. and
- Jefferson Lab
)

- Phys.Lett.B 282 (1992) 453-458
•
DOI:
- 10.1016/0370-2693(92)90668-T

Polarization effects in heavy Lambda decays

Thomas Mannel
(
- Harvard U. and
- DESY
)
,
Winston Roberts
(
- Harvard U.
)
,
Zbigniew Ryzak
(
- Harvard U.
)

- Phys.Lett.B 255 (1991) 593-598
•
DOI:
- 10.1016/0370-2693(91)90273-S

Charm baryons: Theory and experiment

J.G. Korner
(
- Mainz U., Inst. Phys.
)
,
H.W. Siebert
(
- Heidelberg U.
)

- Ann.Rev.Nucl.Part.Sci. 41 (1991) 511-545
•
DOI:
- 10.1146/annurev.ns.41.120191.002455

Semileptonic baryon decays with a heavy quark

Robert L. Singleton
(
- SLAC
)

- Phys.Rev.D 43 (1991) 2939-2950
•
DOI:
- 10.1103/PhysRevD.43.2939

Semileptonic charm baryon decays in the relativistic spectator quark model

- Z.Phys.C 51 (1991) 607-614
•
DOI:
- 10.1007/BF01565586

Predictions for Semileptonic Decays of Charm Baryons. 2. Nonrelativistic and {MIT} Bag Quark Models

- Phys.Rev.D 40 (1989) 2955,
- Phys.Rev.D 44 (1991) 2203 (erratum)
•
DOI:
- 10.1103/PhysRevD.44.2203

Weak Decays of Heavy Mesons in the Static Quark Approximation

Nathan Isgur
(
- Toronto U.
)
,
Mark B. Wise
(
- Caltech
)

- Phys.Lett.B 232 (1989) 113-117
•
DOI:
- 10.1016/0370-2693(89)90566-2

Weak transition form factors between heavy mesons

Nathan Isgur
(
- Toronto U.
)
,
Mark B. Wise
(
- Caltech
)

- Phys.Lett.B 237 (1990) 527-530,
- DPF Conf.1990:0459-464
•
DOI:
- 10.1016/0370-2693(90)91219-2

Review of particle properties. Particle Data Group

et al.

- Phys.Rev.D 45 (1992) S1,
- Phys.Rev.D 46 (1992) 5210 (erratum)
•
DOI:
- 10.1103/PhysRevD.45.S1

ARGUS: A Universal Detector at DORIS-II

ARGUS

Collaboration

•

H. Albrecht
(
- DESY
)

et al.

- Nucl.Instrum.Meth.A 275 (1989) 1-48,
- NUCL. INSTRUM. METHODS A275 (1989) 1-48 AND HAMBURG DESY - DESY 88-080 (88,REC.JUN.) 117p
•
DOI:
- 10.1016/0168-9002(89)90334-3

A Measurement of asymmetry in the decay lambda(c)+ ---> lambda pi+

ARGUS

Collaboration

•

H. Albrecht
(
- DESY
)

et al.

- Phys.Lett.B 274 (1992) 239-245
•
DOI:
- 10.1016/0370-2693(92)90529-D

Measurement of the Lambda(c) decay asymmetry parameter

CLEO

Collaboration

•

P. Avery
(
- Florida U.
)

et al.

- Phys.Rev.Lett. 65 (1990) 2842-2845
•
DOI:
- 10.1103/PhysRevLett.65.2842