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the large hadron collider ( lhc ) will measure the @xmath12 jet production cross section in hadron collisions for various ranges of transverse momenta ( @xmath5 ) with unprecedented statistics and kinematics . with the improvements of @xmath12 tagging pioneered at the tevatron @xcite , the analysis of @xmath12 production with associated muon tags in the lhc environment @xcite is very promising . studies by the cms collaboration have determined that the final states of @xmath12 production can be triggered on and measured out to @xmath4 in the @xmath5 of inclusive @xmath6 meson production by utilizing @xmath12 jet tagging in events containing at least one muon @xcite . the standard model ( sm ) qcd production mechanism for @xmath3 falls rapidly when @xmath13 , thus , studies with restricted @xmath1 ( for such values of @xmath5 and a pseudorapidity ( @xmath14 ) of @xmath2 the variables @xmath5 and @xmath14 are independent from one another ) offer the opportunity to explore the effect that beyond the sm ( bsm ) physics can have on the @xmath5 tail of the @xmath15 distribution .    in utilizing this distribution to search for bsm physics one has to contend with the fact that nlo qcd production leads to a larger background than lo qcd at high @xmath5 due to a @xmath16-channel singularity in @xmath17 . in this paper , we argue that the nlo qcd production background can be significantly reduced through simple kinematic cuts . when the cuts are imposed , the dominant remaining qcd production processes are @xmath10 and bsm physics can more easily produce statistically significant excesses of high @xmath5 events . we restrict our attention to examples of bsm physics with massive new octets under @xmath7 and find that measurements of @xmath15 are quite promising to constrain some @xmath7 octets , affording a @xmath18 discovery reach out to @xmath19 using these cuts . the appearance of new bosons of the form discussed in this paper can be motivated in many scenarios of bsm physics . we concentrate on two models where they appear : a model when a larger gauge group breaks down to qcd as a diagonal subgroup @xcite and the manohar - wise model @xcite which considers minimal flavor violation ( mfv ) @xcite as a global symmetry of new physics that allows specific scalar representations @xcite . we first discuss isolating the signal region by suppressing the nlo qcd production mechanisms through simple kinematic cuts and determine analytically the resulting lo qcd contribution to @xmath15 . we then examine the effect on the calculated distribution due to spin one @xmath7 octets and determine the @xmath18 discovery reach . quarks in both cases can be related through common perturbative fragmentation functions to @xmath6 mesons or other hadronic final states ( or jet functions ) and the relative event rates and discovery reach conclusions will not be significantly effected by this further complication . ]    the tree level effects of some new @xmath7 bosons can be small . this is the case if the strength of the boson s coupling to quarks is proportional to the quark mass . in some models , the largest effect of new physics comes through loop corrections interfering with the sm production mechanisms @xmath10 or one - loop production that is enhanced with an @xmath9-channel resonance . we explore this possibility in detail when the sm is supplemented with an @xmath11 scalar motivated by mfv @xcite . however , for this model , the potential for discovery in this channel is not strong . the dominant contribution to the @xmath15 distribution is qcd production . we first discuss our estimates of the qcd production mechanisms and the isolation of this signal before comparing the bsm signal to this background . when kinematic cuts that we advocate are imposed , the dominant sm production mechanisms are @xmath10 and the bsm signature must be detectable above this background . the hadronic momenta are defined as @xmath20 , where @xmath21 is the hadronic center of mass energy . the momentum of the @xmath12 quark is defined in terms of @xmath22 by p = ( |p_t| , _ t , |p_t| ) . [ loqcd ]        for qcd , the production processes @xmath10 begin at @xmath23 ( see figure 1 ) . alternate heavy flavor production mechanisms through gluon splitting @xmath24 and direct heavy flavor excitation @xmath25 begin at @xmath26 . the contributions from gluon splitting and flavor excitation are dominant when all phase space is integrated over . this has been appreciated theoretically for some time , see @xcite . studies of the total cross section at lhc ( operating at @xmath27 ) using pythia @xcite find that @xmath0 is approximately @xmath28 , with gluon splitting and heavy flavor excitation processes contributing @xmath29 each while the processes @xmath10 contribute @xmath30 . this is mostly due to the @xmath16-channel rutherford scattering enhancement at large @xmath5 for @xmath31 and the effect of pdfs ; @xmath32 is approximately a factor of 200 larger than @xmath33 in the high @xmath5 region . the different processes can be distinguished through their final state kinematics . the processes @xmath10 yield @xmath3 pairs that tend to be back to back and highly symmetric in @xmath5 . in flavor excitation , only one of the quarks undergoes a hard scattering event and the final state @xmath3 pairs are highly asymmetric in @xmath5 . in gluon splitting , the @xmath3 pairs are dominantly produced with an opening angle due to splitting and neither of the quarks undergos a hard scattering interaction . this typically leads to @xmath3 pairs with a small opening angle and small @xmath5 , or both with large @xmath5 but not back to back . using cuts , the different processes can be separated out and a dominant region of @xmath10 production can be isolated . one strategy is to use muonic tags of the @xmath3 decays from the semileptonic @xmath34 decays and @xmath35 decays to allow triggering and to improve the identification and discrimination of @xmath12 jets from backgrounds . a proof of principle is given by an initial cms study that utilizes the opening angle between the @xmath12 quarks to distinguish production mechanisms @xcite . this initial study demonstrates the promise of discriminating the various production mechanisms in a hadron collider environment . note that @xcite insisted on a single @xmath35 decay as it was interested primarily in identifying states with small opening angles . we are interested in @xmath12 jets that are approximately back to back with semi - leptonic muon decays . we advocate a discrimination of the production mechanisms through identified @xmath12 jets by enforcing cuts on the @xmath5 asymmetry and the pseudorapidities of the reconstructed @xmath3 pair of the following form ,    * to isolate the signal region with a small @xmath5 asymmetry enforce @xmath36 where @xmath37 is the total error on the reconstruction of the quark s partonic @xmath5 . the particular value of @xmath38 is not required for our study as the lo production processes we consider trivially satisfy this condition . an optimal value of @xmath38 can be obtained in a nlo study . the error for the @xmath5 asymmetry depends on the decay products and the reconstruction algorithm used ; for the muonic decay tags that we advocate , a cms study @xcite finds a reconstruction error of @xmath39 on @xmath5 of the @xmath6 hadron and fragmentation function errors on the total cross section are on the order of @xmath40 . this cut efficiently reduces the nlo flavor excitation production . * the background due to gluon splitting can be reduced through insisting that the pseudorapidities of the @xmath12 jets lie on different sides of the beam line in the polar angle . this can be done through imposing a cut with @xmath41 on a nlo calculation . the produced @xmath42 pairs will not lie exactly back to back at lo due to the residual boost resulting from the asymmetry of the partonic momenta via pdf effects . these conditions are trivially satisfied by the two - body bsm or qcd production processes for the @xmath5 cuts that we consider while efficiently suppressing the large nlo background from gluon splitting and flavor excitation . further evidence in support of the efficiency of these analytic cuts in isolating the signal region at lhc is supplied by past monte carlo studies of the kinematic properties of the various heavy flavor creation processes at the tevatron @xcite . we compare the effect of bsm bosons on @xmath3 production in the regions with the highest @xmath5 that should be accessible in the cms detector . we restrict the @xmath5 of the final state @xmath3 quarks to generally lie in the range @xmath43 . the pseudorapidity range is the full geometric acceptance of the cms detector for @xmath2 @xcite . it turns out that for such values of @xmath5 and @xmath14 those two quantities are independent from each other and we can impose separate cuts on them . and @xmath5 it is sufficient to take @xmath44 . for @xmath2 this yields @xmath45 . ] the differential cross section of the qcd and bsm processes in terms of the spin and color averaged matrix element @xmath46 ( in terms of partonic mandelstam variables ) is given by [ eq ] = _ 0 ^ 1 d x_2 _ 0 ^ 1 d x_1 f(x_1 , ) f(x_2 , )  . the @xmath47 are the pdfs evaluated at the renormalization scale @xmath48 . as usual , @xmath49 relate the partonic and hadronic momenta so that @xmath50 . integrating over pseudorapidity , the relevant differential cross section for our @xmath5 cuts is given by = _ ^1 d x_2 _ ^1 d x_1 f(x_1 , ) f(x_2 , ) . the lo qcd @xmath51 amplitudes are given in appendix a , section 1 . the results for various integrated luminosities , @xmath5 ranges , and cm energies for the lhc are given in table i.     @xmath52 & lo [ @xmath53 , 1.4 ] & lo [ 1.0 , 1.4 ] + & 200 @xmath54 & 68 & 4.4 + [ 0pt]7 & 10 @xmath55 & @xmath56 & 220 + 10 & 10 @xmath55 & @xmath57 & @xmath58 + 14 & 10 @xmath55 & @xmath59 & @xmath60 +    the contributions of the two - body qcd production mechanism for @xmath0 up to nlo are known @xcite . in comparing our bsm results with the sm qcd background we restrict ourselves to lo qcd for this production process . we also restrict our attention to lo qcd due to collinear singularities in the nlo qcd production processes that are regulated by @xmath61 . we present results of one - loop interference calculations between the sm and bsm physics where the @xmath12 quark mass is neglected . to compare these results consistently with nlo qcd calculations we would need to include final state masses in both calculations as well as contributions from processes with arbitrarily soft extra gluon emission . the dominant nlo qcd production mechanisms that are larger than the lo qcd production mechanisms ( flavour excitation and gluon splitting ) that we are concerned with are suppressed by the cuts we advocate . however , nlo qcd perturbative corrections of the form of virtual corrections and initial and final state radiation corrections to the lo qcd production rate , that do not have these distinct kinematic signatures , will not be highly suppressed by these cuts . including such corrections is beyond the scope and purpose of this work . we treat the spectrum of the bsm physics as an eft with a single @xmath62 singlet or doublet of bosons added to the sm in each case , assuming the cut - off scale is sufficiently high compared to this mass so that higher dimensional operator effects can be neglected . we begin with the case with tree level exchanges of a massive new spin one @xmath7 boson with a purely vector coupling , sometimes referred to as a coloron in the literature . consider supplementing the sm with a massive spin one @xmath7 octet within the spectrum of bsm physics . many models of dynamical electroweak symmetry breaking with new strong interactions have such a particle , for details see @xcite . a sufficient condition for this particle to appear in a bsm spectrum is to have a symmetry breaking pattern where a higgs mechanism is employed for qcd to emerge as a diagonal subgroup @xmath63 . when the resultant spectrum is reduced to its mass eigenstate basis one obtains @xmath64 with the addition of a massive @xmath7 octet . gauge invariance forbids the single coupling of such a particle to gluon pairs and pair production leading to four @xmath12 and four jet signatures of these states has been recently examined in @xcite . consider the case where the coupling of the massive @xmath7 octet has purely vector - like flavor universal coupling and @xmath65 , where @xmath66 is the ratio of the gauge couplings of the underlying @xmath67 gauge groups . then single production of these states from quarks in @xmath68 collisions will give rise to the dominant source of @xmath3 pairs with the kinematics we are interested in . the spin and color averaged matrix element for the excess contribution compared to qcd in the @xmath9-channel in terms of partonic mandelstam variables is ||^2= ( ) ^4 c_f^2 ( + ) , where the width of the coloron is approximated by its quark decays as @xmath69 . for colorons of mass @xmath70 the excess of events in the @xmath5 tail is far larger than the uncertainties of the lo qcd estimate of the background . we define a @xmath18 significance by treating the @xmath71 qcd rate as a poisson distribution . to estimate the effect of large @xmath72 corrections we multiply the @xmath71 qcd rate used in the poisson distribution by @xmath73 $ ] and we take @xmath74 . qcd calculation utilizing the @xmath75 formalism of @xcite which resums the large logs of @xmath76 but this is beyond the scope of this work . such a resummation while running down from the @xmath5 scale to @xmath61 justifies our choice of the renormalization scale at @xmath77 . ] we insist on five signal events after a suppression factor of @xmath78 is applied for the branching ratios of both @xmath12 quarks to final states containing a muon and a total signal efficiency of @xmath79 @xcite for each muon , @xmath12 jet trigger . a @xmath18 discovery of colorons is possible in this channel with a reach out to @xmath80 , however , a significant event rate will require @xmath81 of integrated luminosity because of the suppression of the signal due to selection efficiencies and branching ratios . we show the total integrated luminosity required for various coloron masses and operating energies that pass these tests in figure 2 . other sources of events from the @xmath82 background in the signal region are estimated to be a small @xmath83 level background @xcite . fakes from @xmath84 quarks are reduced with the associated @xmath12 jet trigger and light quark fakes are removed by a @xmath85 cut on the muons . the experimental cross section uncertainty is approximately @xmath86 @xcite for the @xmath5 regions we consider and is dominated by a systematic jet energy scale uncertainty of @xmath87 . [ loqcd ]     tail of @xmath3 production for @xmath5 in the range @xmath88 for cm energies @xmath89 , @xmath90 , and in the range @xmath91 to @xmath92 for @xmath93 . we show the range of coloron masses that can be discovered with @xmath18 significance and at least 5 signal events after branching ratio and event selection suppression of @xmath94 is applied to the signal rate . on the left we take @xmath95 , on the right @xmath96 . our discovery reach is dominated by the requirement of @xmath97 signal events after the suppression of @xmath94 is applied to the signal rate , not pdf or theory uncertainties . for example , the signal to background ratio for the entire discovery reach region for @xmath98 and @xmath99 is @xmath100.,title="fig:",height=204 ]    some of the coloron masses which the tail of the @xmath5 distribution is sensitive to are not ruled out by tevatron studies . the most stringent and most model - independent bounds on the mass scale of flavor universal colorons come from resonance searches in the di - jet invariant mass differential distribution @xcite which obtains a @xmath101 confidence limit exclusion bound on the coloron masses in the range of @xmath102 . we emphasize the complementary nature of searches in this channel to the traditional search strategies for colorons that have focused on @xmath103 pair production . new @xmath7 bosons with tree level couplings to quarks , where @xmath104 , can lead to a large excess of events in the tail of the @xmath8 distribution . for small widths a resonance peak can also be reconstructed . however , when the tree level coupling of a new boson to quarks is proportional to the quark mass , which is frequently the case for spin zero bosons , the largest contribution to high @xmath5 events can come from one - loop production interference effects with the sm lo production processes . this is the case for a @xmath11 scalar representation that couples to quarks proportionally to the yukawa coupling . in this section we explore the possible effects on the tail of the @xmath8 distribution due to such a scalar in one - loop corrections . one - loop effects should not be assumed too small to be detected for heavy flavor production @xmath105 due to our kinematic isolation of a signal region with a suppressed qcd background in the tail of the steeply falling @xmath8 distribution . a direct example of the need of considering naively higher order corrections that experience kinematic enhancements is given by the dominance of nlo qcd corrections over lo qcd in heavy flavor production when all phase space is integrated over . in this particular model , two classes of corrections are of potential interest : a class of one - loop corrections to @xmath106 production that are proportional to an enhanced top yukawa coupling and a separate class experiencing a resonant enhancement in the @xmath9-channel . we investigate these loop effects in detail in the following subsection .      in the manohar - wise model @xcite one adds a single @xmath11 scalar representation to the sm . this representation is the only flavor singlet @xcite scalar representation allowed by mfv other than the higgs . we denote the doublet as ^a = (    c s^+^a + s^0^a    )  , where @xmath107 is the color index . the yukawa sector is determined up to overall complex normalization constants , @xmath108 and @xmath109 , as required by mfv to be l = -_u g_i j^u |u_r i t^a q_j s^a-_d g_i j^d |d_r i t^a q_j s^a + h.c . , where @xmath110 and @xmath111 are the standard model yukawa matrices and @xmath112 are flavor indices . see @xcite for a discussion on the current status of the model s phenomenology . the largest effects of this model on the tail of the @xmath8 distribution do not come from tree level exchanges . this is due in part to the suppression by light quark yukawa couplings . the @xmath113 quark yukawa couplings are far larger but their anti - quark pdfs are highly suppressed in the proton . further , gauge invariance forbids a coupling of a single octet scalar to two gluons . the largest effects on @xmath8 come from two potential sources : one - loop production mechanisms that afford an @xmath9-channel resonance with an @xmath114 exchange , and one - loop interference terms with the qcd production mechanisms which are proportional to @xmath115 due to @xmath116 loops . we discuss the effect of each of these on the tail of the @xmath8 distribution in turn . the largest @xmath9-channel resonant production is shown in figure 3 . scalars.,title="fig:",height=207 ]    from the loop parts of those diagrams , the biggest effect on single production of neutral scalars comes from the top quark loop @xcite . this is also true for the @xmath9-channel exchange and we neglect the effects of the other diagrams that are also proportional to the unknown couplings in the scalar potential of the model ( @xmath117 ) , which are expected to further suppress the contribution of the scalar loop diagrams . the amplitude for the top loop is given by i _ s = _ 0 ^ 1 dx _ 0 ^ 1-x dy where we have taken @xmath14 s real and neglected terms proportional to @xmath118 as discussed in the appendix . we approximate the width of the real scalar by @xmath119 as it is dictated by top decays @xcite . we have determined @xmath120 and used equation ( 3 ) to calculate the resulting contribution of the excess events in the @xmath5 tail . unlike the sm higgs , as the @xmath121 is an 8 under @xmath7 , the amplitude in equation ( 7 ) interferes with the sm heavy flavor production amplitudes given in appendix a , section 1 . this process leads to the change in the number of events given by @xmath122 in table ii and the interference introduces another factor of the quark mass . the resulting event rate is too small to be observed because the resonant enhancement is suppressed by @xmath123 and loop factors . quark final states to have an observable event rate in the @xmath5 tail of the @xmath124 distribution . ] for large masses the parameters @xmath125 can be greater than one , however , the constraints from this model s loop corrections to @xmath126 and @xmath127 ( see , @xcite ) still constrain @xmath128 , so no statistically significant excess is observable in the @xmath5 tail from these processes with final state @xmath12 quarks . the largest non - resonant effect comes from the interference of one - loop corrections due to @xmath129 with the sm lo production processes . these corrections are proportional to @xmath115 . the resulting amplitudes and diagrams are given in the appendix . again , after a rather lengthy calculation we have determined the excess event rate due to these effects using equation ( 3 ) . we summarize in table ii the numbers of expected excess events for the various loop processes . .the change in the number of @xmath3 events due to interference with the octet amplitudes where we restrict @xmath5 between 1.0 and 1.4 @xmath130 , and use an operating energy of @xmath27 for lhc . the results in the table do not have a selection cut or branching ratios to muons applied . the results are given using mstw pdfs for @xmath131 of integrated luminosity . we use @xmath132 , @xmath133 and take @xmath134 . the process for @xmath135 is given in appendix a , section 2 . the process for @xmath136 is given in appendix a , section 3 . we have checked that the processes for @xmath135 and @xmath137 analytically have the correct decoupling behavior . the remaining two processes come from the direct square and the interference of equation ( 7 ) with the lo qcd results in appendix a , section 1 . these are negligible despite the resonance enhancement . we present the results with the unknown @xmath108 and @xmath109 factored out . we also show the constraints on these parameters from allowing a @xmath138 deviation of @xmath127 @xcite and a @xmath139 deviation in @xmath126 @xcite . light octets are not ruled out by direct production and are consistent with ewpd down to @xmath140 @xcite . all of these mechanisms do not lead to a statistically significant excess of events in the @xmath5 tail of @xmath42 production . [ cols="^,^,^,^,^,^",options="header " , ]     for the @xmath5 range of integration @xmath141 the results are not large enough to be detected , despite the highly suppressed background and the enhancement of these loop effects . the lo qcd background to compare these results to is given in table i. the experimental uncertainty of the cross section in the high @xmath5 region has a systematic uncertainty on the order of @xmath142 . no statistically significant excess is expected in this model in the @xmath5 tail . our results additionally imply that these effects on the @xmath3 cross section determined at the tevatron are also negligible , affording no significant constraint on the model . heavy flavor production at hadron colliders has a long history of surprises and challenges to both theorists and experimentalists . due to the long standing difficulties of accommodating the measured @xmath143 at the tevatron within our understanding of qcd , which have only recently been overcome , exploring high @xmath5 production of @xmath42 pairs at the lhc as a constraint on bsm physics demands great caution . despite this , one can impose simple kinematic cuts to improve the discovery reach of heavy flavor production by suppressing the nlo qcd flavor excitation and gluon splitting processes . this allows one to more efficiently exploit @xmath12 tagging with associated muons which affords a significant @xmath5 reach for final state @xmath6 mesons at lhc . we have determined the reach for a @xmath144 discovery of flavor universal colorons using this technique at lo in qcd . we have also demonstrated that the effects on @xmath3 production in the manohar - wise model are not large enough to afford a statistically significant deviation from the expected qcd production background .    for the @xmath5 reach in @xmath8 to be fully exploited in the lhc era , further work on precision studies of heavy flavor production in the standard model is of increased importance in light of this discovery potential . improvements of the sm calculations of heavy flavor production and the associated systematic uncertainties would have to be carefully examined at lhc before any evidence of new physics could be claimed . however , our results are promising for further work to develop the heavy flavor production program at lhc with this aim for discovery of new massive @xmath7 bosons with tree level couplings to quarks not proportional to the quark mass .      we thank mark wise for collaboration during the early stages of the work presented here . we further thank mark wise , maxim pospelov , saba zuberi and brian batell for comments on the manuscript . research at the perimeter institute is supported in part by the government of canada through nserc and by the province of ontario through medt . the lo and nlo qcd results for @xmath0 are well known in the literature @xcite . we summarize the simple lo results for completeness and to explain a trick @xcite that we employ to simplify our subsequent one - loop calculations . as discussed in section ii , cuts on the @xmath5 asymmetry and the opening angle of the reconstructed @xmath3 pair can isolate the kinematic region where the dominant qcd ( or bsm ) production mechanisms are the @xmath10 processes . the lo results for these processes in qcd are given by @xmath145 \ , \left[\bar{u}(p ) \ , \gamma_{\mu } \ , t^a \ , v(\bar{p } ) \right ] , \nonumber\\ i   \mathcal{m}^{gg}_{sm}&=&-i g_s^2\ , \bar{u}(p)\bigg[[t^a , t^b]\frac{1}{s } \left(g^{\mu\nu}(\slashed{p}_1-\slashed{p}_2)+2\gamma^{\nu}p_2^{\mu}-2\gamma^{\mu}p_1^{\nu}\right)\nonumber\\ & & \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ + \,t^bt^a\frac{1}{t } \gamma^{\nu}(\slashed{p}_1-\slashed{\bar{p}})\gamma^{\mu}+ t^at^b\frac{1}{u}\gamma^{\mu}(\slashed{p}-\slashed{p}_1)\gamma^{\nu}\bigg ] v(\bar{p})\ .\end{aligned}\ ] ]    note that in @xmath146 we have modified the triple gluon vertex of qcd to eliminate the dependence on @xmath147 . this does not change the final answer once the gluon is summed over physical polarizations as the difference is proportional to @xmath148 and @xmath149 @xcite . this trick does , however , allow us to sum over the physical and non - physical polarizations of the gluon as the spurious contributions to the amplitude , which are proportional to this momentum dependence , are removed . when calculating the interference of the lo qcd processes with such a modification , this trick allows one to set to zero all factors of @xmath147 in our results for the one - loop interference effects of the @xmath11 scalar with qcd , and sum over all polarizations of the gluon , simplifying significantly intermediate steps of the calculation . our one - loop result for the modification of @xmath151 ( see figure 4 ) is given as the following gauge invariant amplitude ( where we have set all external masses to zero ) @xmath152 \ ,   \left[\bar{v}_i(p_2 ) \ , \gamma_\mu \ , t^a u_i ( p_1 ) \right]\nonumber\\ & & \times \bigg[c_a \bigg [ a_1(m_s^2,m_t^2 ) -a_1(m_t^2,m_s^2 ) + a_2(m_s^2,m_t^2)+ \frac{1}{2 } \bigg]\nonumber\\ & & + \,\,c_f \bigg[\ , 2 \ , a_1(m_t^2,m_s^2 ) - \,2 \ , a_2(m_s^2,m_t^2 ) + \frac{3m_t^2-m_s^2}{2(m_s^2-m_t^2)}\,\bigg]\nonumber\\ & & + \,\,c_f\bigg[\,\frac{m_s^2(m_s^2 - 2m_t^2)}{(m_s^2-m_t^2)^2}\ln\left(\frac{m_s^2}{\mu^2}\right ) + \frac{m_t^4}{(m_s^2-m_t^2)^2}\ln\left(\frac{m_t^2}{\mu^2}\right ) \bigg]\bigg ] \ , \end{aligned}\ ] ] where a_1(m_s^2,m_t^2 ) & = & _ 0 ^ 1 dx ( ) + & & -_0 ^ 1 dx ( ) , + a_2(m_s^2,m_t^2 ) & = & - _ 0 ^ 1 dx + ( ) + & & + _ 0 ^ 1 dx ( ) , and for the @xmath7 case @xmath153 . the formulas for the @xmath158-channel diagrams are obtained from the @xmath16-channel results by substituting @xmath159 . we define the following feynman parameter volumes as a short hand d v(x , y ) & = & _ 0 ^ 1 dx _ 0 ^ 1-x dy , + d v(x , y , z ) & = & _ 0 ^ 1 dx _ 0 ^ 1-x dy _ 0 ^ 1-x - y dz . our @xmath16-channel results are as follows ( again , after setting all external masses to zero ) . the expressions below should be contracted with @xmath160 . @xmath161x t\bigg]\ , \nonumber\\ \mathcal{m}^t_{e}&= & \frac { c_a \ , t^b \ , t^a}{t } \ , \bigg[\bar{u}_l(p ) \gamma_{\nu}(\slashed{p}_1-\slashed{\bar{p}})\gamma_{\mu}v_l(\bar{p } )   \ , \int d v(x , y ) \ , \ln\left(\frac { f_2(x , y)}{\mu^2}\right)\nonumber\\ & & + \ , \int d v(x , y ) \ , \frac{1}{f_2(x , y ) } \bar{u}_l(p)\gamma_{\mu}v_l(\bar{p})[(p_1-\bar{p})_{\nu}(2x-1)+p_{\nu}(2y-1)]x t\bigg]\ , \nonumber\\ \mathcal{m}^t_{f}&= & \frac{\left ( 2 \ , c_f - c_a\right)t^bt^a}{t } \bigg[\bar{u}_l(p ) \gamma_{\nu}(\slashed{p}_1-\slashed{\bar{p}})\gamma_{\mu}v_l(\bar{p})\ ,   \int d v(x , y ) \ ,   \left [ \ln \left(\frac{f_{3}(x , y)}{\mu^2}\right)+1\right ] \nonumber\\ & & - \int d v(x , y ) \ ,   \frac{1 } { f_{3}(x , y)}\bar{u}_l(p ) \gamma_{\nu}(\slashed{p}_1-\slashed{\bar{p } } ) [ \slashed{p}_1(1-x)-\slashed{\bar{p}}y+m_t]\gamma_{\mu}[-\slashed{p}_1x - \slashed{\bar{p}}y + m_t]v_l(\bar{p } ) \bigg]\ , \nonumber\\ \mathcal{m}^t_{g}&= & \frac{\left(2 \ , c_f - c_a\right)t^bt^a}{t } \bigg [ \bar{u}_l(p ) \gamma_{\nu}(\slashed{p}_1-\slashed{\bar{p}})\gamma_{\mu}v_l(\bar{p})\int d v(x , y ) \ , \left[\ln \left(\frac{f_{4}(x , y)}{\mu^2}\right)+1\right]\nonumber\\ & & - \int d v(x , y ) \ ,   \frac{1 } { f_{4}(x , y)}\bar{u}_l(p ) [ \slashed{p}_2x+\slashed{p}y+m_t]\gamma_{\nu}[\slashed{p}_2(x-1)+\slashed{p}y+m_t ] ( \slashed{p}_1-\slashed{\bar{p}})\gamma_{\mu}v_l(\bar{p } ) \bigg]\ , \nonumber\\ \mathcal{m}^t_{h}&=&0\ , \end{aligned}\ ] ] where @xmath162    the @xmath9-channel and @xmath16-channel box diagram results are @xmath163 - \bar{u}_l(p)\gamma_{\mu}v_l(\bar{p})\bigg[\frac{p_{\nu}(1-x - y)+\bar{p}_{\nu}z}{2f_{5}(x , y , z)}\bigg ] \nn \\ & & + \,\bar{u}_l(p)\slashed{p}_1v_l(\bar{p})\bigg [ \frac{x g_{\mu\nu}}{2f_{5}(x , y , z)}+\frac{x\left[\bar{p}_{\mu}(1-x - z)+p_{\mu } y\right ] \left[p_{\nu}(1-x - y)+\bar{p}_{\nu}z\right]}{[f_{5}(x , y , z)]^2}\bigg ] \ , \bigg ] ,   \nn \\ ! \left[(2 c_f - c_a)t^bt^a   + \frac{c_a}{2}\delta^{ba}\right]\!\int \!d v(x , y , z)\bigg [ \frac{1}{f_{6}(x , y , z)}\bar{u}_l(p ) \gamma_{\nu}\gamma_{\mu}[\slashed{p}_1(y+z-1)-\slashed{p}_2 x ]   v_l(\bar{p } ) \bigg . \nn \\ & & \bigg.+\frac{1}{f_{6}(x , y , z)}\bar{u}_l(p)\big[\gamma_{\mu}[\slashed{p}_1 z - \slashed{p}_2 ( x+y)+\slashed{p}y]\gamma_{\nu}+ [ \slashed{p}_1 z + \slashed{p}_2(1-x - y)]\gamma_{\nu } \gamma_{\mu}\big]v_l(\bar{p } ) \bigg . \nn \\ & & \bigg.+ \frac{1}{[f_{6}(x , y , z)]^2 } \bar{u}_l(p ) m_t^2 \big [ [ \slashed{p}_2(1-x - y)+\slashed{p}_1 z]\gamma_{\nu}\gamma_{\mu } + \gamma_{\nu}[-\slashed{p}_2 ( x+y ) + \slashed{p}_1 z + \slashed{p } y]\gamma_{\mu}\big]v_l(\bar{p } ) \bigg . \nn \\ & & \bigg.+ \frac{1}{[f_{6}(x , y , z)]^2 } \bar{u}_l(p ) m_t^2\gamma_{\nu}\gamma_{\mu}[-\slashed{p}_1 ( 1-y - z)-\slashed{p}_2 x]v_l(\bar{p } ) \bigg . \nn \\ & & \bigg.\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!+ \frac{1}{[f_{6}(x , y , z)]^2 } \bar{u}_l(p ) [ \slashed{p}_2(1-x - y)+\slashed{p}_1 z ] \gamma_{\nu}[-\slashed{p}_2(x+y)+\slashed{p}_1 z + \slashed{p}y]\gamma_{\mu}[-\slashed{p}_2 x - \slashed{p}_1(1-y - z ) ] v_l(\bar{p } ) \bigg ] , \nonumber\\ \mathcal{m}^t_{k}&= & - 8 \ , c_a \ , \delta^{ab } \int d v(x , y , z )   \bigg [ \frac{1}{f_{7}(x , y , z ) } \ , \bar{u}_l(p ) \ , \gamma_{\mu}[p_2^{\nu}(2y+2z-1)-2\bar{p}^{\nu}y+2p^{\nu}x ]   v_l(\bar{p } ) \bigg . \nn \\ & & + \bigg . \,\frac{1}{f_{7}(x , y , z ) } \ ,   \bar{u}_l(p)\big[\gamma_{\nu}\gamma_{\mu}[-\slashed{p}_2(y+z-1)-\slashed{p}x+m_t ] + [ -\slashed{p}_2(y+z)+\slashed{\bar{p}}y+m_t]\gamma_{\mu}\gamma_{\nu}\big]v_l(\bar{p } ) \bigg . \nn \\ & & + \,\frac{1}{[f_{7}(x , y , z)]^2}\bar{u}_l(p)[-\slashed{p}_2(y+z)+\slashed{\bar{p}}y+m_t]\gamma_{\mu } [ -\slashed{p}_2(y+z-1)-\slashed{p}x+m_t][2\bar{p}^{\nu}y-2p^{\nu}x]v_l(\bar{p } ) \bigg ] , \nonumber\\ \mathcal{m}^s_{l , m}\!&=&\!\!-\frac{2 c_f}{s } \ , \left[t^a , t^b\right ] \bar{u}_l(p)\left[g^{\mu\nu } ( \slashed{p}_1-\slashed{p}_2)+2\gamma^{\nu}p_2^{\mu}-2\gamma^{\mu}p_1^{\nu}\right]v_l(\bar{p } ) \int_0 ^ 1 dx \ , x \ ,   \ln \left(\frac{m_s^2x+m_t^2(1-x)}{\mu^2}\right),\nonumber\\ \mathcal{m}^s_{n}&=&\frac{c_a}{s } \left[t^a , t^b\right ] \bar{u}_l(p)\left[g^{\mu\nu } ( \slashed{p}_1-\slashed{p}_2)+2\gamma^{\nu}p_2^{\mu}-2\gamma^{\mu}p_1^{\nu}\right]v_l(\bar{p } ) \int d v(x , y ) \ , \ln \left(\frac{f_8(x , y)}{\mu^2}\right ) , \nonumber\\ \mathcal{m}^s_{o}&= & \frac{\left ( 2 c_f - c_a\right)}{s } \ , \left[t^a , t^b\right ] \ , \bar{u}_l(p)\left[g^{\mu\nu } ( \slashed{p}_1-\slashed{p}_2)+2\gamma^{\nu}p_2^{\mu}-2\gamma^{\mu}p_1^{\nu}\right]v_l(\bar{p } ) \nn \\ & & \times \int d v(x , y ) \ , \bigg[\ln \left(\frac{f_9(x , y)}{\mu^2}\right)+1- \frac{m_t^2 + s x y } { f_9(x , y)}\bigg]\ , \!\!\!\!\!\!\!\!\!\!\!\!\!\end{aligned}\ ] ] where @xmath164
we discuss the potential of measurements of @xmath0 to constrain new bosonic degrees of freedom at the lhc when @xmath1 for a pseudorapidity cut @xmath2 . by suppressing the nlo qcd production of @xmath3 pairs through simple kinematic constraints 
 we show how to more efficiently exploit cms s reach out to @xmath4 in @xmath5 for @xmath6 mesons in searches for new physics . using this technique 
 we investigate the potential for discovery of new massive spin one and spin zero @xmath7 octet bosons by analyzing their effect on the @xmath8 distribution . in some cases , the tree level contributions are small and the largest effect of new physics on the @xmath5 tail of the distribution is due to one - loop resonant @xmath9-channel production or interference effects with the lo standard model production mechanisms @xmath10 . 
 we explore this possibility in some detail when the standard model is extended with an @xmath11 scalar motivated by minimal flavor violation .