Search for third generation scalar leptoquarks decaying to a top quark and a tau lepton at sqrt(s) = 13 TeV

Search for third generation scalar leptoquarks decaying to a top quark and a tau lepton at sqrt(s) = 13 TeV

CMS

Collaboration

2017

20 pages

Report number:

CMS-PAS-B2G-16-028

Experiments:

CERN-LHC-CMS

View in:

CERN Document Server

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Abstract:

A search for pair production of heavy scalar leptoquarks (LQs) decaying into a top quark and a

\tau

lepton is presented. The search considers final states with an electron or a muon, one or two

\tau

leptons decaying to hadrons, and additional jets. The data collected in proton-proton collisions in 2016 at

{\sqrt{s}=13}~\mathrm{TeV}

with the CMS detector at the LHC, corresponding to an integrated luminosity of

35.9~\mathrm{fb}^{-1}

are used. No evidence for pair production of leptoquarks is found. Upper limits on the production cross section are set as a function of LQ mass, assuming a branching fraction of unity for the decay

\mathrm{LQ}\to \mathrm{t} \tau

, excluding masses below

900~\mathrm{GeV}

at

95\%

confidence level. These results provide the most stringent exclusion limits on the production of scalar leptoquarks in the top quark and

\tau

lepton decay channel to date.

Note:

Preliminary results

Data
p p: colliding beams
leptoquark: scalar
leptoquark: pair production
leptoquark: decay
tau: hadronic decay
final state: ((n)jet lepton)
p p: scattering
family: 3
leptoquark: branching ratio

References(73)

Figures(13)

[1]

Leptoquarks in Lepton - Quark Collisions

W. Buchmuller
(
- Hannover U. and
- DESY
)
,
R. Ruckl
(
- DESY
)
,
D. Wyler
(
- Zurich, ETH
)

- Phys.Lett.B 191 (1987) 442-448,
- Phys.Lett.B 448 (1999) 320-320 (erratum)
•
DOI:
- 10.1016/0370-2693(87)90637-X

[2]

Lepton Number as the Fourth Color

Jogesh C. Pati
(
- Maryland U.
)
,
Abdus Salam
(
- ICTP, Trieste and
- Imperial Coll., London
)

- Phys.Rev.D 10 (1974) 275-289,
- Phys.Rev.D 11 (1975) 703-703 (erratum)
•
DOI:
- 10.1103/PhysRevD.10.275

[3]

Unity of All Elementary Particle Forces

H. Georgi
(
- Harvard U.
)
,
S.L. Glashow
(
- Harvard U.
)

- Phys.Rev.Lett. 32 (1974) 438-441,
- Also in *Lichtenberg, D.B. (ed.), Rosen, S.P. (ed.): Developments In The Quark Theory Of Hadrons, Vol. 1*, 492-495, and in *Froggatt, C.D., Nielsen, H.B.: Origin of symmetries* 330-333
•
DOI:
- 10.1103/PhysRevLett.32.438

[4]

Unified Interactions of Leptons and Hadrons

Harald Fritzsch
(
- Caltech
)
,
Peter Minkowski
(
- Caltech
)

- Annals Phys. 93 (1975) 193-266,
- In *Mohapatra, R. N. ( Ed.), Lai, C. H. ( Ed.): Gauge Theories Of Fundamental Interactions*, 432-505
•
DOI:
- 10.1016/0003-4916(75)90211-0

[5]

Technicolor

Edward Farhi
(
- CERN
)
,
Leonard Susskind
(
- Stanford U., ITP
)

- Phys.Rept. 74 (1981) 277
•
DOI:
- 10.1016/0370-1573(81)90173-3

[6]

Walking technicolor signatures at hadron colliders

Kenneth D. Lane
(
- Boston U.
)
,
M.V. Ramana
(
- Boston U.
)

- Phys.Rev.D 44 (1991) 2678-2700
•
DOI:
- 10.1103/PhysRevD.44.2678

[7]

LIGHT LEPTOQUARKS

Barbara Schrempp
(
- Hamburg U.
)
,
Fridger Schrempp
(
- Hamburg U.
)

- Phys.Lett.B 153 (1985) 101-107
•
DOI:
- 10.1016/0370-2693(85)91450-9

[8]

Composite Leptoquarks at the LHC

Ben Gripaios
(
- CERN
)

- JHEP 02 (2010) 045
•
e-Print:
- 0910.1789
•
DOI:
- 10.1007/JHEP02(2010)045

[9]

Evidence for an excess of $\bar{B} \to D^{(*)} \tau^-\bar{\nu}_\tau$ decays

BaBar

Collaboration

•

J.P. Lees
(
- Annecy, LAPP
)

et al.

- Phys.Rev.Lett. 109 (2012) 101802
•
e-Print:
- 1205.5442
•
DOI:
- 10.1103/PhysRevLett.109.101802

[10]

Measurement of an Excess of $\bar{B} \to D^{(*)}\tau^- \bar{\nu}_\tau$ Decays and Implications for Charged Higgs Bosons

BaBar

Collaboration

•

J.P. Lees
(
- Annecy, LAPP
)

et al.

- Phys.Rev.D 88 (2013) 7, 072012
•
e-Print:
- 1303.0571
•
DOI:
- 10.1103/PhysRevD.88.072012

[11]

Observation of B0 ---> D*- tau+ nu(tau) decay at Belle

Belle

Collaboration

•

A. Matyja

et al.

- Phys.Rev.Lett. 99 (2007) 191807
•
e-Print:
- 0706.4429
•
DOI:
- 10.1103/PhysRevLett.99.191807

[12]

Observation of $B^+ \to \bar{D}^*0 \tau^+ \nu_\tau$ and Evidence for $B^+ \to \bar{D}^0 \tau^+ \nu_\tau$ at Belle

Belle

Collaboration

•

A. Bozek
(
- Cracow, INP
)

et al.

- Phys.Rev.D 82 (2010) 072005
•
e-Print:
- 1005.2302
•
DOI:
- 10.1103/PhysRevD.82.072005

[13]

Measurement of the branching ratio of $\bar{B} \to D^{(\ast)} \tau^- \bar{\nu}_\tau$ relative to $\bar{B} \to D^{(\ast)} \ell^- \bar{\nu}_\ell$ decays with hadronic tagging at Belle

Belle

Collaboration

•

M. Huschle
(
- Karlsruhe U., EKP
)

et al.

- Phys.Rev.D 92 (2015) 7, 072014
•
e-Print:
- 1507.03233
•
DOI:
- 10.1103/PhysRevD.92.072014

[14]

Measurement of the ratio of branching fractions $\mathcal{B}(\bar{B}^0 \to D^{+}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}^0 \to D^{+}\mu^{-}\bar{\nu}_{\mu})$

LHCb

Collaboration

•

Roel Aaij
(
- CERN
)

et al.

- Phys.Rev.Lett. 115 (2015) 11, 111803,
- Phys.Rev.Lett. 115 (2015) 15, 159901 (erratum)
•
e-Print:
- 1506.08614
•
DOI:
- 10.1103/PhysRevLett.115.111803