Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto

G. Aad; T. Abajyan; B. Abbott; J. Abdallah; S.A. Khalek; Mogens Dam; Jørgen Beck Hansen; Peter Henrik Hansen; John Renner Hansen; Jørn Dines Hansen; Simon Johann Franz Heisterkamp; Morten Dam Jørgensen; Nele Maria Philomena Boelaert; Esben Bryndt Klinkby; Ask Emil Løvschall-Jensen; Sascha Mehlhase; Björn Stefan Nilsson; Troels Christian Petersen; Stefania Xella

doi:10.1103/PhysRevD.88.112003

Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto

G. Aad, T. Abajyan, B. Abbott, J. Abdallah, S.A. Khalek, Mogens Dam, Jørgen Beck Hansen, Peter Henrik Hansen, John Renner Hansen, Jørn Dines Hansen, Simon Johann Franz Heisterkamp, Morten Dam Jørgensen, Nele Maria Philomena Boelaert, Esben Bryndt Klinkby, Ask Emil Løvschall-Jensen, Sascha Mehlhase, Björn Stefan Nilsson, Troels Christian Petersen, Stefania Xella

Experimental Particle Physics

73 Citations (Scopus)

Abstract

An updated search is performed for gluino, top squark, or bottom squark R-hadrons that have come to rest within the ATLAS calorimeter, and decay at some later time to hadronic jets and a neutralino, using 5.0 and 22:9 fb^-1 of pp collisions at 7 and 8 TeV, respectively. Candidate decay events are triggered in selected empty bunch crossings of the LHC in order to remove pp collision backgrounds. Selections based on jet shape and muon system activity are applied to discriminate signal events from cosmic ray and beam-halo muon backgrounds. In the absence of an excess of events, improved limits are set on gluino, stop, and sbottom masses for different decays, lifetimes, and neutralino masses. With a neutralino of mass 100 GeV, the analysis excludes gluinos with mass below 832 GeV (with an expected lower limit of 731 GeV), for a gluino lifetime between 10 μs and 1000 s in the generic R-hadron model with equal branching ratios for decays to (formula presented) and (formula presented). Under the same assumptions for the neutralino mass and squark lifetime, top squarks and bottom squarks in the Regge R-hadron model are excluded with masses below 379 and 344 GeV, respectively.

Original language	English
Article number	112003
Journal	Physical Review D (Particles, Fields, Gravitation and Cosmology)
Volume	88
Issue number	11
Pages (from-to)	88
Number of pages	11
ISSN	1550-7998
DOIs	https://doi.org/10.1103/PhysRevD.88.112003
Publication status	Published - 3 Dec 2013

Access to Document

10.1103/PhysRevD.88.112003

Cite this

Aad, G., Abajyan, T., Abbott, B., Abdallah, J., Khalek, S. A., Dam, M., Hansen, J. B., Hansen, P. H., Hansen, J. R., Hansen, J. D., Heisterkamp, S. J. F., Jørgensen, M. D., Boelaert, N. M. P., Klinkby, E. B., Løvschall-Jensen, A. E., Mehlhase, S., Nilsson, B. S., Petersen, T. C., & Xella, S. (2013). Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto. Physical Review D (Particles, Fields, Gravitation and Cosmology), 88(11), 88. Article 112003. https://doi.org/10.1103/PhysRevD.88.112003

Aad, G, Abajyan, T, Abbott, B, Abdallah, J, Khalek, SA, Dam, M , Hansen, JB , Hansen, PH , Hansen, JR , Hansen, JD, Heisterkamp, SJF, Jørgensen, MD, Boelaert, NMP, Klinkby, EB, Løvschall-Jensen, AE, Mehlhase, S, Nilsson, BS, Petersen, TC & Xella, S 2013, 'Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto', Physical Review D (Particles, Fields, Gravitation and Cosmology), vol. 88, no. 11, 112003, pp. 88. https://doi.org/10.1103/PhysRevD.88.112003

@article{612f8016820d40c1ae0b0393cb379d65,

title = "Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto",

abstract = "An updated search is performed for gluino, top squark, or bottom squark R-hadrons that have come to rest within the ATLAS calorimeter, and decay at some later time to hadronic jets and a neutralino, using 5.0 and 22:9 fb-1 of pp collisions at 7 and 8 TeV, respectively. Candidate decay events are triggered in selected empty bunch crossings of the LHC in order to remove pp collision backgrounds. Selections based on jet shape and muon system activity are applied to discriminate signal events from cosmic ray and beam-halo muon backgrounds. In the absence of an excess of events, improved limits are set on gluino, stop, and sbottom masses for different decays, lifetimes, and neutralino masses. With a neutralino of mass 100 GeV, the analysis excludes gluinos with mass below 832 GeV (with an expected lower limit of 731 GeV), for a gluino lifetime between 10 μs and 1000 s in the generic R-hadron model with equal branching ratios for decays to (formula presented) and (formula presented). Under the same assumptions for the neutralino mass and squark lifetime, top squarks and bottom squarks in the Regge R-hadron model are excluded with masses below 379 and 344 GeV, respectively.",

author = "G. Aad and T. Abajyan and B. Abbott and J. Abdallah and S.A. Khalek and Mogens Dam and Hansen, {J{\o}rgen Beck} and Hansen, {Peter Henrik} and Hansen, {John Renner} and Hansen, {J{\o}rn Dines} and Heisterkamp, {Simon Johann Franz} and J{\o}rgensen, {Morten Dam} and Boelaert, {Nele Maria Philomena} and Klinkby, {Esben Bryndt} and L{\o}vschall-Jensen, {Ask Emil} and Sascha Mehlhase and Nilsson, {Bj{\"o}rn Stefan} and Petersen, {Troels Christian} and Stefania Xella",

year = "2013",

month = dec,

day = "3",

doi = "10.1103/PhysRevD.88.112003",

language = "English",

volume = "88",

pages = "88",

journal = "Physical Review D (Particles, Fields, Gravitation and Cosmology)",

issn = "1550-7998",

publisher = "American Physical Society",

number = "11",

}

TY - JOUR

T1 - Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto

AU - Aad, G.

AU - Abajyan, T.

AU - Abbott, B.

AU - Abdallah, J.

AU - Khalek, S.A.

AU - Dam, Mogens

AU - Hansen, Jørgen Beck

AU - Hansen, Peter Henrik

AU - Hansen, John Renner

AU - Hansen, Jørn Dines

AU - Heisterkamp, Simon Johann Franz

AU - Jørgensen, Morten Dam

AU - Boelaert, Nele Maria Philomena

AU - Klinkby, Esben Bryndt

AU - Løvschall-Jensen, Ask Emil

AU - Mehlhase, Sascha

AU - Nilsson, Björn Stefan

AU - Petersen, Troels Christian

AU - Xella, Stefania

PY - 2013/12/3

Y1 - 2013/12/3

N2 - An updated search is performed for gluino, top squark, or bottom squark R-hadrons that have come to rest within the ATLAS calorimeter, and decay at some later time to hadronic jets and a neutralino, using 5.0 and 22:9 fb-1 of pp collisions at 7 and 8 TeV, respectively. Candidate decay events are triggered in selected empty bunch crossings of the LHC in order to remove pp collision backgrounds. Selections based on jet shape and muon system activity are applied to discriminate signal events from cosmic ray and beam-halo muon backgrounds. In the absence of an excess of events, improved limits are set on gluino, stop, and sbottom masses for different decays, lifetimes, and neutralino masses. With a neutralino of mass 100 GeV, the analysis excludes gluinos with mass below 832 GeV (with an expected lower limit of 731 GeV), for a gluino lifetime between 10 μs and 1000 s in the generic R-hadron model with equal branching ratios for decays to (formula presented) and (formula presented). Under the same assumptions for the neutralino mass and squark lifetime, top squarks and bottom squarks in the Regge R-hadron model are excluded with masses below 379 and 344 GeV, respectively.

AB - An updated search is performed for gluino, top squark, or bottom squark R-hadrons that have come to rest within the ATLAS calorimeter, and decay at some later time to hadronic jets and a neutralino, using 5.0 and 22:9 fb-1 of pp collisions at 7 and 8 TeV, respectively. Candidate decay events are triggered in selected empty bunch crossings of the LHC in order to remove pp collision backgrounds. Selections based on jet shape and muon system activity are applied to discriminate signal events from cosmic ray and beam-halo muon backgrounds. In the absence of an excess of events, improved limits are set on gluino, stop, and sbottom masses for different decays, lifetimes, and neutralino masses. With a neutralino of mass 100 GeV, the analysis excludes gluinos with mass below 832 GeV (with an expected lower limit of 731 GeV), for a gluino lifetime between 10 μs and 1000 s in the generic R-hadron model with equal branching ratios for decays to (formula presented) and (formula presented). Under the same assumptions for the neutralino mass and squark lifetime, top squarks and bottom squarks in the Regge R-hadron model are excluded with masses below 379 and 344 GeV, respectively.

U2 - 10.1103/PhysRevD.88.112003

DO - 10.1103/PhysRevD.88.112003

M3 - Journal article

SN - 1550-7998

VL - 88

SP - 88

JO - Physical Review D (Particles, Fields, Gravitation and Cosmology)

JF - Physical Review D (Particles, Fields, Gravitation and Cosmology)

IS - 11

M1 - 112003

ER -

Search for long-lived stopped R-hadrons decaying out of time with pp collisions using the ATLAS detecto

Abstract

Access to Document

Fingerprint

Cite this