# Changes between Version 2 and Version 3 of kkg_FV

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Timestamp:
11/03/15 16:11:04 (19 months ago)
Comment:

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Unmodified
 v2 Colored vector bosons from new strong dynamics, Kaluza-Klein gluons or KKg’s (G*) in a dual 5D picture, have been searched for mainly in the t-tbar channel.  The analysis in [http://arxiv.org/pdf/1409.7607v2.pdf 1409.7607v2] analyzes the tc decay as depicted below: [[Image(wiki:KKg.png)]] In this model, the third generation quarks couple differently than the light quarks under an extended The benchmark adopted here is a simple renormalizable model of an extended color gauge sector, which realizes next-to-minimal flavor violation (NMFV). In this model, the third generation quarks couple differently than the light quarks under an extended {{{ #!latex $SU(3)_1 \times SU(3)_2$ }}} color gauge group.  The mixing between light and third generation quarks is induced by the interactions of all three generation quarks with a set of new heavy vector0like quarks.  The model reproduces the CKM mixing and generates flavor-changing neutral currents (FCNCs) from non-standard interactions.  Due to the specific structure of the model, dangerous FCNCs are naturally suppressed and a large portion of the model parameter space is allowed by the data on meson mixing process and on color gauge group.  The mixing between light and third generation quarks is induced by the interactions of all three generation quarks with a set of new heavy vector-like quarks.  The model reproduces the CKM mixing and generates flavor-changing neutral currents (FCNCs) from non-standard interactions.  Due to the specific structure of the model, dangerous FCNCs are naturally suppressed and a large portion of the model parameter space is allowed by the data on meson mixing process and on {{{ #!latex $b \to \gamma$. $b \to s\gamma$. }}} The model has the color gauge structure {{{ #!latex $SU(3)_1 \times SU(3)_2$ }}} The extended color symmetry is broken down to {{{ #!latex $\bf 3, \bar{3}$ $(\bf 3, \bar{3})$ }}} under the color gauge structure.  It is assumed that color gauge breaking occurs at a scale much higher than the electroweak scale. under the color gauge structure.  It is assumed that color gauge breaking occurs at a scale much higher than the electroweak scale, u>>v. Breaking the color symmetry induces a mixing between the $\cot\omega = \frac{g_1}{g_2} \qquad g_s = g_1 \sin\omega = g_2 \cos\omega$, }}} where g_s is the QCD strong coupling and g_1 and g_2 are the SU(3)_1 and SU(3)_2 gauge couplings, respectively.  The mixing diagonalization reveals two color vector boson mass eigenstates: the mass-less SM gluon and a new massive color-octet vector boson G* given by where g_s is the QCD strong coupling and g_1, g_2 are the SU(3)_1 and SU(3)_2 gauge couplings, respectively.  The mixing diagonalization reveals two color vector boson mass eigenstates: the mass-less SM gluon and a new massive color-octet vector boson G* given by {{{ #!latex G*'s form an extended color group and can be produced at the LHC by quark-antiquark fusion determined by the G* coupling to light quarks The G* can be produced at the LHC by quark-antiquark fusion determined by the G* coupling to light quarks {{{ #!latex $\Gamma[G^{*} \to t_L \bar c_L]=\Gamma[G^{*} \to c_L \bar t_L]\simeq \left(V_{cb}\right)^2 \frac{g^2_s}{48\pi} M_{G^{*}} \left( \cot\omega+\tan\omega \right)^2,$ }}} where V_cb=0.0415$is the CKM matrix element. Note here that G* FCNCs are induced by the mixing among left-handed quarks generated by the exchange of heavy vector-like quarks. This mixing is controlled by the 3x3 matrices U_L and D_L in the up- and down-quark sectors, respectively. In particular, the G* to tc flavor violating decay is controlled by the where {{{ #!latex$V_{cb}=0.0415$}}} is the CKM matrix element. Note here that G* FCNCs are induced by the mixing among left-handed quarks generated by the exchange of heavy vector-like quarks. This mixing is controlled by the 3x3 matrices U_L and D_L in the up- and down-quark sectors, respectively. In particular, the {{{ #!latex$G* \to tc$}}} flavor violating decay is controlled by the {{{ #!latex {{{ #!latex$b\to s \gamma$. \rm{So }$(D_L)_{23}b\to s \gamma$. }}} So {{{ #!latex$(D_L)_{23}$}}} is thus forced to be small and, as a consequence,$(U_L)_{23}\simeq V_{cb}\$. }}} See more details in * [http://arxiv.org/pdf/1409.7607v2.pdf 1409.7607v2] * [http://arxiv.org/pdf/1412.3094.pdf 1412.3094] == Note == == Model Files == Need to reread and make sure everything is the same as paper. * [attachment:proc_card_mg5.dat proc_card]: for generation of 500 GeV KKg (place in Cards/) * [attachment:run_card.dat run_card]: for generation of 500 GeV KKg (place in Cards/) * [attachment:kkg_FV.zip kkg_FV]: the model and parameter cards for specific mass generations == Generation specifics == In [http://arxiv.org/pdf/1409.7607v2.pdf 1409.7607v2], the samples were generated with the mass as the scale, dsqrt_q2fact1, and dsqrt_q2fact2 in the run_card.  These samples were also generated without the pre-included !MadGraph cuts as demonstrated in the run_card.dat for 500 GeV mass included above.  The specific generations run were {{{ p p > kkg > b~ c l- vl~ @1 p p > kkg > b c~ l+ vl @2 }}} To generate a specific mass, param_card.dat in the generation file to the card of the appropriate mass in the param_cards directory (included as part of the model zip file).