Search for scalar top and scalar bottom quarks using the OPAL detector at LEP

被引：10

作者：

Ackerstaff, K

Alexander, G

Allison, J

Altekamp, N

Ametewee, K

Anderson, KJ

Anderson, S

Arcelli, S

Asai, S

Axen, D

Azuelos, G

Ball, AH

Barberio, E

Barlow, RJ

Bartoldus, R

Batley, JR

Bechtluft, J

Beeston, C

Behnke, T

Bell, AN

Bell, KW

Bella, G

Bentvelsen, S

Berlich, P

Bethke, S

Biebel, O

Blobel, V

Bloodworth, IJ

Bloomer, JE

Bobinski, I

Bock, P

Bosch, HM

Boutemeur, M

Bouwens, BT

Braibant, S

Brown, RM

Burckharth, HJ

Burgard, C

Burgin, R

Capiluppi, P

Carnegie, RK

Carter, AA

Carter, JR

Chang, CY

Charlton, DG

Chrisman, D

Clarke, PEL

Cohen, I

Conboy, JE

Cooke, OC

机构：

[1] UNIV BOLOGNA,DIPARTMENTO FIS,I-40126 BOLOGNA,ITALY

[2] IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY

[3] UNIV BONN,INST PHYS,D-53115 BONN,GERMANY

[4] UNIV CALIF RIVERSIDE,DEPT PHYS,RIVERSIDE,CA 92521

[5] UNIV CAMBRIDGE,CAVENDISH LAB,CAMBRIDGE CB3 0HE,ENGLAND

[6] CARLETON UNIV,DEPT PHYS,OTTAWA CARLETON INST PHYS,OTTAWA,ON K1S 5B6,CANADA

[7] CARLETON UNIV,CTR RES PARTICLE PHYS,OTTAWA,ON K1S 5B6,CANADA

[8] CERN,EUROPEAN ORG PARTICLE PHYS,CH-1211 GENEVA 23,SWITZERLAND

[9] UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637

[10] UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637

[11] UNIV FREIBURG,FAK PHYS,D-79104 FREIBURG,GERMANY

[12] UNIV HEIDELBERG,INST PHYS,D-69120 HEIDELBERG,GERMANY

[13] INDIANA UNIV,DEPT PHYS,BLOOMINGTON,IN 47405

[14] UNIV LONDON QUEEN MARY & WESTFIELD COLL,LONDON E1 4NS,ENGLAND

[15] RHEIN WESTFAL TH AACHEN,INST PHYS 3,D-52056 AACHEN,GERMANY

[16] UNIV LONDON UNIV COLL,LONDON WC1E 6BT,ENGLAND

[17] UNIV MANCHESTER,DEPT PHYS,SCHUSTER LAB,MANCHESTER M13 9PL,LANCS,ENGLAND

[18] UNIV MARYLAND,DEPT PHYS,COLLEGE PK,MD 20742

[19] UNIV MONTREAL,PHYS NUCL LAB,MONTREAL,PQ H3C 3J7,CANADA

[20] UNIV OREGON,DEPT PHYS,EUGENE,OR 97403

[21] RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND

[22] TECHNION ISRAEL INST TECHNOL,DEPT PHYS,IL-32000 HAIFA,ISRAEL

[23] TEL AVIV UNIV,DEPT PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL

[24] INT CTR ELEMENTARY PARTICLE PHYS,TOKYO 113,JAPAN

[25] UNIV TOKYO,DEPT PHYS,TOKYO 113,JAPAN

[26] KOBE UNIV,KOBE 657,JAPAN

[27] BRUNEL UNIV,UXBRIDGE UB8 3PH,MIDDX,ENGLAND

[28] WEIZMANN INST SCI,PARTICLE PHYS DEPT,IL-76100 REHOVOT,ISRAEL

[29] UNIV HAMBURG,DESY,INST EXPT PHYS 2,D-22607 HAMBURG,GERMANY

[30] UNIV VICTORIA,DEPT PHYS,VICTORIA,BC V8W 3P6,CANADA

[31] UNIV BRITISH COLUMBIA,DEPT PHYS,VANCOUVER,BC V6T 1Z1,CANADA

[32] UNIV ALBERTA,DEPT PHYS,EDMONTON,AB T6G 2J1,CANADA

[33] DUKE UNIV,DEPT PHYS,DURHAM,NC 27708

[34] RES INST PARTICLE & NUCL PHYS,H-1525 BUDAPEST,HUNGARY

[35] INST NUCL RES,H-4001 DEBRECEN,HUNGARY

[36] UNIV MUNICH,SEKT PHYS,D-85748 GARCHING,GERMANY

来源：

PHYSICS LETTERS B | 1996年 / 389卷 / 01期

关键词：

D O I：

10.1016/S0370-2693(96)01395-0

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The scalar top quark can be the Lightest charged supersymmetric particle and it can be lighter than the top quark itself in supersymmetric extensions of the Standard Model. A search for a scalar top quark has been performed using a total data sample of 15.2 pb(-1) at centre-of-mass energies of root s=130, 136, and 161 GeV collected with the OPAL detector at LEP. No evidence was found above the background level expected from the Standard Model, The 95% C.L. lower limit on the scalar top quark mass is 58.7 GeV, if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is smaller than pi/4. If the mixing angle is zero, the limit is 65.4 GeV, These limits were obtained on the condition that the scalar top quark decays into a charm quark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. Assuming a relatively light scalar neutrino, we also studied the complementary decay mode of the scalar top quark in which it decays into a bottom quark, a charged lepton, and a scalar neutrino, A mass limit on the light scalar bottom quark was also set in this study.

引用

页码：197 / 210

页数：14

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