Abstract
This thesis presents a measurement of the lifetime of the B hadron by usage of the mini-vertex detector and a new identification method for B hadrons by means of the hadronic decay into a J/{psi}. The clear signature of the J/{psi}decay into a lepton pair is used in order to select 106 such events of the ALEPH data set of the years 1990 and 1991. The inclusive branching ratio of the J/{psi}production in the Z{sup 0} decay results to: Br(Z{sup 0}{yields}J{psi}X)=(3.5{+-}0.35{+-}0.23)x10{sub -3}. The resulting inclusive branching ratio for B hadrons into J/{psi}mesons Br(B{yields}J{psi}X)=(1.13{+-}0.12{+-}0.08)% is compatible with the world mean value of (1.12{+-}0.16)%. Under usage of a simultaneous fit of the signal and background lifetime by the maximum-likelihood method the inclusive lifetime of the B hadrons is determined to: {tau}{sub B}=(1.26{sub -0.16}{sup +0.18}{+-}0.05)ps. With the measured value of the lifetime and the semileptonic branching ratio for the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.044{+-}0.007{+-}0.003 is obtained. If the differential branching ratio dBr( anti B{sup 0}{yields}D{sup *+}l anti {nu})/dq{sup 2} is used for the determination of the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.042{+-}0.007{+-}0.003 is obtained. (HSI)
Citation Formats
Lauber, J.
Measurement of the mean lifetime of bottom hadrons by the reaction Z{sup 0} {yields}b anti b {yields}J/{psi}X by usage of the silicon vertex detector in ALEPH at the LEP storage ring; Messung der mittleren Lebensdauer von Bottom-Hadronen mit der Reaktion Z{sup 0} {yields}b anti b {yields}J/{psi}X unter Benutzung des Silizium-Vertex-Detektors in ALEPH am LEP-Speicherring.
Germany: N. p.,
1993.
Web.
Lauber, J.
Measurement of the mean lifetime of bottom hadrons by the reaction Z{sup 0} {yields}b anti b {yields}J/{psi}X by usage of the silicon vertex detector in ALEPH at the LEP storage ring; Messung der mittleren Lebensdauer von Bottom-Hadronen mit der Reaktion Z{sup 0} {yields}b anti b {yields}J/{psi}X unter Benutzung des Silizium-Vertex-Detektors in ALEPH am LEP-Speicherring.
Germany.
Lauber, J.
1993.
"Measurement of the mean lifetime of bottom hadrons by the reaction Z{sup 0} {yields}b anti b {yields}J/{psi}X by usage of the silicon vertex detector in ALEPH at the LEP storage ring; Messung der mittleren Lebensdauer von Bottom-Hadronen mit der Reaktion Z{sup 0} {yields}b anti b {yields}J/{psi}X unter Benutzung des Silizium-Vertex-Detektors in ALEPH am LEP-Speicherring."
Germany.
@misc{etde_10131471,
title = {Measurement of the mean lifetime of bottom hadrons by the reaction Z{sup 0} {yields}b anti b {yields}J/{psi}X by usage of the silicon vertex detector in ALEPH at the LEP storage ring; Messung der mittleren Lebensdauer von Bottom-Hadronen mit der Reaktion Z{sup 0} {yields}b anti b {yields}J/{psi}X unter Benutzung des Silizium-Vertex-Detektors in ALEPH am LEP-Speicherring}
author = {Lauber, J}
abstractNote = {This thesis presents a measurement of the lifetime of the B hadron by usage of the mini-vertex detector and a new identification method for B hadrons by means of the hadronic decay into a J/{psi}. The clear signature of the J/{psi}decay into a lepton pair is used in order to select 106 such events of the ALEPH data set of the years 1990 and 1991. The inclusive branching ratio of the J/{psi}production in the Z{sup 0} decay results to: Br(Z{sup 0}{yields}J{psi}X)=(3.5{+-}0.35{+-}0.23)x10{sub -3}. The resulting inclusive branching ratio for B hadrons into J/{psi}mesons Br(B{yields}J{psi}X)=(1.13{+-}0.12{+-}0.08)% is compatible with the world mean value of (1.12{+-}0.16)%. Under usage of a simultaneous fit of the signal and background lifetime by the maximum-likelihood method the inclusive lifetime of the B hadrons is determined to: {tau}{sub B}=(1.26{sub -0.16}{sup +0.18}{+-}0.05)ps. With the measured value of the lifetime and the semileptonic branching ratio for the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.044{+-}0.007{+-}0.003 is obtained. If the differential branching ratio dBr( anti B{sup 0}{yields}D{sup *+}l anti {nu})/dq{sup 2} is used for the determination of the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.042{+-}0.007{+-}0.003 is obtained. (HSI)}
place = {Germany}
year = {1993}
month = {Sep}
}
title = {Measurement of the mean lifetime of bottom hadrons by the reaction Z{sup 0} {yields}b anti b {yields}J/{psi}X by usage of the silicon vertex detector in ALEPH at the LEP storage ring; Messung der mittleren Lebensdauer von Bottom-Hadronen mit der Reaktion Z{sup 0} {yields}b anti b {yields}J/{psi}X unter Benutzung des Silizium-Vertex-Detektors in ALEPH am LEP-Speicherring}
author = {Lauber, J}
abstractNote = {This thesis presents a measurement of the lifetime of the B hadron by usage of the mini-vertex detector and a new identification method for B hadrons by means of the hadronic decay into a J/{psi}. The clear signature of the J/{psi}decay into a lepton pair is used in order to select 106 such events of the ALEPH data set of the years 1990 and 1991. The inclusive branching ratio of the J/{psi}production in the Z{sup 0} decay results to: Br(Z{sup 0}{yields}J{psi}X)=(3.5{+-}0.35{+-}0.23)x10{sub -3}. The resulting inclusive branching ratio for B hadrons into J/{psi}mesons Br(B{yields}J{psi}X)=(1.13{+-}0.12{+-}0.08)% is compatible with the world mean value of (1.12{+-}0.16)%. Under usage of a simultaneous fit of the signal and background lifetime by the maximum-likelihood method the inclusive lifetime of the B hadrons is determined to: {tau}{sub B}=(1.26{sub -0.16}{sup +0.18}{+-}0.05)ps. With the measured value of the lifetime and the semileptonic branching ratio for the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.044{+-}0.007{+-}0.003 is obtained. If the differential branching ratio dBr( anti B{sup 0}{yields}D{sup *+}l anti {nu})/dq{sup 2} is used for the determination of the CKM matrix element vertical stroke V{sub cb}vertical stroke =0.042{+-}0.007{+-}0.003 is obtained. (HSI)}
place = {Germany}
year = {1993}
month = {Sep}
}