Improved sensitivity to charged Higgs searches in top quark decays t → bH+ → b(τ+ ντ) at the LHC using τ polarisation and multivariate techniques

被引：10

作者：

Ali, Ahmed ^{[1
]}

Barreiro, Fernando ^{[2
]}

Llorente, Javier ^{[2
]}

机构：

[1] Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany

[2] Univ Autonoma Madrid, Dept Fis, Fac Ciencias C 11, E-28049 Madrid, Spain

来源：

EUROPEAN PHYSICAL JOURNAL C | 2011年 / 71卷 / 09期

关键词：

QCD CORRECTIONS; BOSON DECAY; SIGNATURE; CMS;

D O I：

10.1140/epjc/s10052-011-1737-8

中图分类号：

O412 [相对论、场论]; O572.2 [粒子物理学];

学科分类号：

摘要：

We present an analysis with improved sensitivity to the light charged Higgs (m(H+) < m(t) - m(b)) searches in the top quark decays t -> bH(+) -> b(tau(+) nu tau) + c.c. in the t<(t)over bar> and single t/(t) over bar t production processes at the LHC. In the Minimal Supersymmetric Standard Model (MSSM), one anticipates the branching ratio B(H+ -> tau(+) nu tau) similar or equal to 1 over almost the entire allowed tan beta range. Noting that the tau(+) arising from the decay H+ -> tau(+) nu tau are predominantly right-polarized, as opposed to the t+ from the dominant background W+ -> tau(+) nu tau, which are left-polarized, a number of H+/W+ -> tau(+)nu tau discriminators have been proposed and studied in the literature. We consider hadronic decays of the tau(+/-), concentrating on the dominant one-prong decay channel tau(+/-) -> rho(+/-)nu(tau) The energy and p(T) of the charged prongs normalised to the corresponding quantities of the rho(+/-) are convenient variables which serve as tau(+/-) polariser. We use the distributions in these variables and several other kinematic quantities to train a boosted decision tree (BDT). Using the BDT classifier, and a variant of it called BDTD, which makes use of decorrelated variables, we have calculated the BDT(D)-response functions to estimate the signal efficiency vs. the rejection of the background. We argue that this chain of analysis has a high sensitivity to light charged Higgs searches up to a mass of 150 GeV in the decays t -> bH(+) (and charge conjugate) at the LHC. For the case of single top production, we also study the transverse mass of the system determined using Lagrange multipliers.

引用

页码：1 / 19

页数：19

共 57 条

[1] Observation of Electroweak Single Top-Quark Production [J].

Aaltonen, T. ;

Adelman, J. ;

Akimoto, T. ;

Alvarez Gonzalez, B. ;

Amerio, S. ;

Amidei, D. ;

Anastassov, A. ;

Annovi, A. ;

Antos, J. ;

Apollinari, G. ;

Apresyan, A. ;

Arisawa, T. ;

Artikov, A. ;

Ashmanskas, W. ;

Attal, A. ;

Aurisano, A. ;

Azfar, F. ;

Badgett, W. ;

Barbaro-Galtieri, A. ;

Barnes, V. E. ;

Barnett, B. A. ;

Barria, P. ;

Bartsch, V. ;

Bauer, G. ;

Beauchemin, P. -H. ;

Bedeschi, F. ;

Beecher, D. ;

Behari, S. ;

Bellettini, G. ;

Bellinger, J. ;

Benjamin, D. ;

Beretvas, A. ;

Beringer, J. ;

Bhatti, A. ;

Binkley, M. ;

Bisello, D. ;

Bizjak, I. ;

Blair, R. E. ;

Blocker, C. ;

Blumenfeld, B. ;

Bocci, A. ;

Bodek, A. ;

Boisvert, V. ;

Bolla, G. ;

Bortoletto, D. ;

Boudreau, J. ;

Boveia, A. ;

Brau, B. ;

Bridgeman, A. ;

Brigliadori, L. .

PHYSICAL REVIEW LETTERS, 2009, 103 (09)

[2] Search for Charged Higgs Bosons in Decays of Top Quarks in pp Collisions at s=1.96 TeV [J].

Aaltonen, T. ;

Adelman, J. ;

Akimoto, T. ;

Alvarez Gonzalez, B. ;

Amerio, S. ;

Amidei, D. ;

Anastassov, A. ;

Annovi, A. ;

Antos, J. ;

Apollinari, G. ;

Apresyan, A. ;

Arisawa, T. ;

Artikov, A. ;

Ashmanskas, W. ;

Attal, A. ;

Aurisano, A. ;

Azfar, F. ;

Azzurri, P. ;

Badgett, W. ;

Barbaro-Galtieri, A. ;

Barnes, V. E. ;

Barnett, B. A. ;

Bartsch, V. ;

Bauer, G. ;

Beauchemin, P. -H. ;

Bedeschi, F. ;

Beecher, D. ;

Behari, S. ;

Bellettini, G. ;

Bellinger, J. ;

Benjamin, D. ;

Beretvas, A. ;

Beringer, J. ;

Bhatti, A. ;

Binkley, M. ;

Bisello, D. ;

Bizjak, I. ;

Blair, R. E. ;

Blocker, C. ;

Blumenfeld, B. ;

Bocci, A. ;

Bodek, A. ;

Boisvert, V. ;

Bolla, G. ;

Bortoletto, D. ;

Boudreau, J. ;

Boveia, A. ;

Brau, B. ;

Bridgeman, A. ;

Brigliadori, L. .

PHYSICAL REVIEW LETTERS, 2009, 103 (10)

[3] Observation of Single Top-Quark Production [J].

Abazov, V. M. ;

Abbott, B. ;

Abolins, M. ;

Acharya, B. S. ;

Adams, M. ;

Adams, T. ;

Aguilo, E. ;

Ahsan, M. ;

Alexeev, G. D. ;

Alkhazov, G. ;

Alton, A. ;

Alverson, G. ;

Alves, G. A. ;

Ancu, L. S. ;

Andeen, T. ;

Anzelc, M. S. ;

Aoki, M. ;

Arnoud, Y. ;

Arov, M. ;

Arthaud, M. ;

Askew, A. ;

Asman, B. ;

Atramentov, O. ;

Avila, C. ;

BackusMayes, J. ;

Badaud, F. ;

Bagby, L. ;

Baldin, B. ;

Bandurin, D. V. ;

Banerjee, P. ;

Banerjee, S. ;

Barberis, E. ;

Barfuss, A. -F. ;

Bargassa, P. ;

Baringer, P. ;

Barreto, J. ;

Bartlett, J. F. ;

Bassler, U. ;

Bauer, D. ;

Beale, S. ;

Bean, A. ;

Begalli, M. ;

Begel, M. ;

Belanger-Champagne, C. ;

Bellantoni, L. ;

Bellavance, A. ;

Benitez, J. A. ;

Beri, S. B. ;

Bernardi, G. ;

Bernhard, R. .