The Collider Detector at Fermilab collected a unique sample of jets originating from bottom-quark fragmentation (b-jets) by selecting online proton-antiproton (p (p) over bar) collisions with a vertex displaced from p (p) over bar interaction point, consistent with the decay of a bottom-quark hadron. This data set, collected at a center-of-mass energy of 1.96 TeV, and corresponding to an integrated luminosity of 5.4 fb(-1), is used to measure the Z-boson production cross section times branching ratio into b (b) over bar. The number of Z -> b (b) over bar events is determined by fitting the dijet-mass distribution, while constraining the dominant b-jet background, originating from QCD multijet events, with data. The result, sigma(p(p)over bar> -> Z) x B(Z -> b (b) over bar) = 1.11 +/- 0.08(stat) +/- 0.14(syst) nb, is the most precise measurement of this process, and is consistent with the standard-model prediction. The data set is also used to search for Higgs-boson production. No significant signal is expected in our data and the first upper limit on the cross section for the inclusive p(p)over bar>-> H -> b (b) over bar process at root s = 1.96 TeV is set, corresponding to 33 times the expected standard-model cross section, or sigma = 40.6 pb, at the 95% confidence level.

Search for standard-model Z and Higgs bosons decaying into a bottom-antibottom quark pair in proton-antiproton collisions at 1.96 TeV / Aaltonen, T., Amerio, S., Amidei, D., Anastassov, A., Annovi, A., Antos, J., Apollinari, G., Appel, J.A., Arisawa, T., Artikov, A., Asaadi, J., Ashmanskas, W., Auerbach, B., Aurisano, A., Azfar, F., Badgett, W., Bae, T., Barbaro-Galtieri, A., Barnes, V.E., Barnett, B.A., et al.. - In: PHYSICAL REVIEW D. - ISSN 2470-0010. - 98:7(2018). [10.1103/PhysRevD.98.072002]

Search for standard-model Z and Higgs bosons decaying into a bottom-antibottom quark pair in proton-antiproton collisions at 1.96 TeV

Giagu, S.;Iori, M.;Rescigno, M.;
2018

Abstract

The Collider Detector at Fermilab collected a unique sample of jets originating from bottom-quark fragmentation (b-jets) by selecting online proton-antiproton (p (p) over bar) collisions with a vertex displaced from p (p) over bar interaction point, consistent with the decay of a bottom-quark hadron. This data set, collected at a center-of-mass energy of 1.96 TeV, and corresponding to an integrated luminosity of 5.4 fb(-1), is used to measure the Z-boson production cross section times branching ratio into b (b) over bar. The number of Z -> b (b) over bar events is determined by fitting the dijet-mass distribution, while constraining the dominant b-jet background, originating from QCD multijet events, with data. The result, sigma(p(p)over bar> -> Z) x B(Z -> b (b) over bar) = 1.11 +/- 0.08(stat) +/- 0.14(syst) nb, is the most precise measurement of this process, and is consistent with the standard-model prediction. The data set is also used to search for Higgs-boson production. No significant signal is expected in our data and the first upper limit on the cross section for the inclusive p(p)over bar>-> H -> b (b) over bar process at root s = 1.96 TeV is set, corresponding to 33 times the expected standard-model cross section, or sigma = 40.6 pb, at the 95% confidence level.
2018
B(b)over-bar production; parton distributions: root-S=8 Tev; jets
01 Pubblicazione su rivista::01a Articolo in rivista
Search for standard-model Z and Higgs bosons decaying into a bottom-antibottom quark pair in proton-antiproton collisions at 1.96 TeV / Aaltonen, T., Amerio, S., Amidei, D., Anastassov, A., Annovi, A., Antos, J., Apollinari, G., Appel, J.A., Arisawa, T., Artikov, A., Asaadi, J., Ashmanskas, W., Auerbach, B., Aurisano, A., Azfar, F., Badgett, W., Bae, T., Barbaro-Galtieri, A., Barnes, V.E., Barnett, B.A., et al.. - In: PHYSICAL REVIEW D. - ISSN 2470-0010. - 98:7(2018). [10.1103/PhysRevD.98.072002]
File allegati a questo prodotto
File Dimensione Formato  
Giagu_Standard-model-Z.pdf

accesso aperto

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 416.21 kB
Formato Adobe PDF
416.21 kB Adobe PDF

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1211600
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 1
social impact