Search for bosonic stop decays in R-parity violating supersymmetry in e+ p collisions at HERA

A search for scalar top quarks in R-parity violating supersymmetry is performed in e+p collisions at HERA using the H1 detector. The data, taken at s=319GeV and 301 GeV, correspond to an integrated luminosity of 106pb−1 . The resonant production of scalar top quarks t˜ in positron quark fusion via an R-parity violating Yukawa coupling λ′ is considered with the subsequent bosonic stop decay t˜→b˜W . The R-parity violating decay of the sbottom quark b˜→dν¯e and leptonic and hadronic W decays are considered. No evidence for stop production is found in the search for bosonic stop decays nor in a search for the direct R-parity violating decay t˜→eq . Mass dependent limits on λ′ are obtained in the framework of the minimal supersymmetric Standard Model. Stop quarks with masses up to 275GeV can be excluded at the 95% confidence level for a Yukawa coupling of electromagnetic strength.

Note:

20 pages, 5 figures and 2 tables

positron p: colliding beams
positron p: inclusive reaction
squark: search for
squark: top
squark: decay modes
squark: bottom
supersymmetry
R parity: violation
coupling: Yukawa
squark: mass

References(27)

Figures(6)

Supersymmetry, Supergravity and Particle Physics

Hans Peter Nilles
(
- Geneva U. and
- CERN
)

- Phys.Rept. 110 (1984) 1-162
•
DOI:
- 10.1016/0370-1573(84)90008-5

The Search for Supersymmetry: Probing Physics Beyond the Standard Model

Howard E. Haber
(
- UC, Santa Cruz and
- SLAC
)
,
Gordon L. Kane
(
- Michigan U.
)

- Phys.Rept. 117 (1985) 75-263
•
DOI:
- 10.1016/0370-1573(85)90051-1

Search for squark production in R parity violating supersymmetry at HERA

H1

Collaboration

•

A. Aktas

et al.

- Eur.Phys.J.C 36 (2004) 425-440
•
e-Print:
- hep-ex/0403027
•
DOI:
- 10.1140/epjc/s2004-01982-2

Searches at HERA for squarks in R-parity violating supersymmetry

H1

Collaboration

•

C. Adloff

et al.

- Eur.Phys.J.C 20 (2001) 639-657
•
e-Print:
- hep-ex/0102050
•
DOI:
- 10.1007/s100520100716

Isolated electrons and muons in events with missing transverse momentum at HERA

H1

Collaboration

•

V. Andreev

et al.

- Phys.Lett.B 561 (2003) 241-257
•
e-Print:
- hep-ex/0301030
•
DOI:
- 10.1016/S0370-2693(03)00497-0

Possible excess in charged current events with high Q**2 at HERA from stop and sbottom production

Tadashi Kon
(
- Seikei U.
)
,
Takashi Matsushita
(
- Tokyo Metropolitan U.
)
,
Tetsuro Kobayashi
(
- Fukui Inst. Tech.
)

- Mod.Phys.Lett.A 12 (1997) 3143-3152
•
e-Print:
- hep-ph/9707355
•
DOI:
- 10.1142/S0217732397003265

R-parity violation at HERA

J. Butterworth
(
- Oxford U.
)
,
Herbert K. Dreiner
(
- Oxford U.
)

- Nucl.Phys.B 397 (1993) 3-34
•
e-Print:
- hep-ph/9211204
•
DOI:
- 10.1016/0550-3213(93)90334-L

The H1 detector at HERA

H1

Collaboration

•

I. Abt

et al.

- Nucl.Instrum.Meth.A 386 (1997) 310-347
•
DOI:
- 10.1016/S0168-9002(96)00893-5

The H1 lead / scintillating fiber calorimeter

et al.

- Nucl.Instrum.Meth.A 386 (1997) 397-408
•
DOI:
- 10.1016/S0168-9002(96)01171-0

Hard diffractive scattering in high-energy e p collisions and the Monte Carlo generator RAPGAP

Hannes Jung
(
- DESY
)

- Comput.Phys.Commun. 86 (1995) 147-161
•
DOI:
- 10.1016/0010-4655(94)00150-Z

A Model for Initial State Parton Showers

Torbjorn Sjostrand
(
- Fermilab
)

- Phys.Lett.B 157 (1985) 321-325
•
DOI:
- 10.1016/0370-2693(85)90674-4

ARIADNE version 4: A Program for simulation of QCD cascades implementing the color dipole model

Leif Lonnblad
(
- DESY
)

- Comput.Phys.Commun. 71 (1992) 15-31,
- Comput. Phys. Commun. 71 (1992) 15-31 and Hamburg DESY - DESY 92-046 (92/02,rec.Apr.) 15 p
•
DOI:
- 10.1016/0010-4655(92)90068-A

Heracles: An Event Generator for $e p$ Interactions at {HERA} Energies Including Radiative Processes: Version 1.0

- Comput.Phys.Commun. 69 (1992) 155-172,
- Comput. Phys. Commun. 69 (1992) 155-172 and Hamburg DESY - DESY 90-041 (90,rec.May) 16 p
•
DOI:
- 10.1016/0010-4655(92)90136-M