<chapter name="Extra-Dimensional Processes"> 
 
<h2>Extra-Dimensional Processes</h2> 
 
Scenarios with extra dimensions (ED) allow a multitude of processes. 
Currently three different categories of processes are implemented. 
The first involves the production of excited Kaluza Klein states 
within so-called Randall-Sundrum (RS) scenarios, the second is 
related to resonance production in TeV-1 sized extra dimensions 
and the third relates to phenomena from large extra dimensions (LED). 
Due to the close relation between the LED model and a so-called 
unparticle model, similar unparticle processes are also kept in this 
section. 
 
<h3>Randall-Sundrum Resonances, production processes</h3> 
 
The graviton (G*) and gluon (KKgluon*) resonance states are assigned 
PDG code 5100039 and 5100021 respectively. The G* processes are 
described in <ref>Bij01</ref> and the KKgluon* process in <ref>Ask11</ref>. 
Decays into fermion and boson pairs are handled with the correct 
angular distributions, while subsequent decays are handled 
isotropically. 
 
<p/> 
There are two lowest-order processes that together normally 
should be sufficient for a simulation of <ei>G^*</ei> production. 
 
<flag name="ExtraDimensionsG*:all" default="off"> 
Common switch for the group of lowest-order <ei>G^*</ei> production 
processes, i.e. the two ones below. 
</flag> 
 
<flag name="ExtraDimensionsG*:gg2G*" default="off"> 
Scatterings <ei>g g &rarr; G^*</ei>. 
Code 5001. 
</flag> 
 
<flag name="ExtraDimensionsG*:ffbar2G*" default="off"> 
Scatterings <ei>f fbar &rarr; G^*</ei>. 
Code 5002. 
</flag> 
 
<p/> 
In addition there are three first-order processes included. These 
are of less interest, but can be used for dedicated studies of the 
high-<ei>pT</ei> tail of <ei>G^*</ei> production. As usual, it would 
be double counting to include the lowest-order and first-order 
processes simultaneously. Therefore the latter ones are not included 
with the <code>ExtraDimensionsG*:all = on</code> option. In this set 
of processes all decay angles are assumed isotropic. 
 
<flag name="ExtraDimensionsG*:gg2G*g" default="off"> 
Scatterings <ei>g g &rarr; G^* g</ei>. 
Code 5003. 
</flag> 
 
<flag name="ExtraDimensionsG*:qg2G*q" default="off"> 
Scatterings <ei>q g &rarr; G^* q</ei>. 
Code 5004. 
</flag> 
 
<flag name="ExtraDimensionsG*:qqbar2G*g" default="off"> 
Scatterings <ei>q qbar &rarr; G^* g</ei>. 
Code 5005. 
</flag> 
 
<p/> 
There is also one process for the production of a gluon resonance. 
 
<flag name="ExtraDimensionsG*:qqbar2KKgluon*" default="off"> 
Scatterings <ei>q qbar &rarr; g^*/KKgluon^*</ei>. 
Code 5006. 
</flag> 
 
<h3>Randall-Sundrum Resonances, parameters</h3> 
 
In the above scenario the main free parameters are the masses, which 
are set as usual. In addition there are the following coupling parameters. 
The coupling <ei>kappaMG</ei> follows the conventions in <ref>Bij01</ref>, 
where as the flavour dependent couplings follow the conventions used in 
<ref>Dav01</ref>. 
 
<flag name="ExtraDimensionsG*:SMinBulk" default="off"> 
Parameter to choose between the two scenarios: 
<ei>off</ei>, SM on the TeV brane (common <ei>kappaMG</ei> coupling); 
<ei>on</ei>, SM in the ED bulk (flavour dependent couplings). 
This parameter is only relevant for the lowest-order graviton 
(<ei>G*</ei>) processes, where as the first-order processes 
corresponds to the <ei>off</ei> scenario. 
</flag> 
 
<flag name="ExtraDimensionsG*:VLVL" default="on"> 
Parameter to specify Z/W coupling scenario: 
<ei>off</ei>, usual Z/W boson couplings; 
<ei>on</ei>, coupling only to longitudinal Z/W bosons. 
In both cases the <ei>GZZ</ei> and <ei>GWW</ei> values are used 
and this parameter is only relevant when <ei>SMinBulk = on</ei>. 
The formulas for longitudinal bosons should be appropriate up to 
<ei>O(m_V/E_V)</ei> corrections. 
</flag> 
 
<parm name="ExtraDimensionsG*:kappaMG" default="0.054" min="0.0"> 
dimensionless coupling, which enters quadratically in all on-shell 
partial widths of the <ei>G^*</ei>. Is 
<ei>kappa m_G* = sqrt(2) x_1 k / Mbar_Pl</ei>, 
where <ei>x_1 = 3.83</ei> is the first zero of the <ei>J_1</ei> Bessel 
function and <ei>Mbar_Pl</ei> is the modified Planck mass. 
In width and cross section calculations, <ei>kappa</ei> is fixed by 
the on-shell <ei>G^*</ei> mass and <ei>kappaMG</ei>, i.e. 
<ei>kappaMG</ei> scales with the off-shell <ei>G^*</ei> mass. 
</parm> 
 
<parm name="ExtraDimensionsG*:Gll" default="0.0" min="0.0"> 
Coupling between graviton and leptons. 
</parm> 
 
<parm name="ExtraDimensionsG*:Gqq" default="0.0" min="0.0"> 
Coupling between graviton and light quarks. 
</parm> 
 
<parm name="ExtraDimensionsG*:Gbb" default="0.0" min="0.0"> 
Coupling between graviton and bottom quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:Gtt" default="0.001" min="0.0"> 
Coupling between graviton and top quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:Ggg" default="0.000013" min="0.0"> 
Coupling between graviton and gluon. 
</parm> 
 
<parm name="ExtraDimensionsG*:Ggmgm" default="0.000013" min="0.0"> 
Coupling between graviton and gamma. 
</parm> 
 
<parm name="ExtraDimensionsG*:GZZ" default="0.001" min="0.0"> 
Coupling between graviton and Z boson. 
</parm> 
 
<parm name="ExtraDimensionsG*:GWW" default="0.001" min="0.0"> 
Coupling between graviton and W boson. 
</parm> 
 
<parm name="ExtraDimensionsG*:Ghh" default="0.001" min="0.0"> 
Coupling between graviton and Higgs bosons. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgqR" default="-0.2"> 
Coupling between KK-gluon and a right-handed light quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgqL" default="-0.2"> 
Coupling between KK-gluon and a left-handed light quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgbR" default="-0.2"> 
Coupling between KK-gluon and a right-handed bottom quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgbL" default="1.0"> 
Coupling between KK-gluon and a left-handed bottom quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgtR" default="4.0"> 
Coupling between KK-gluon and a right-handed top quark. 
</parm> 
 
<parm name="ExtraDimensionsG*:KKgtL" default="1.0"> 
Coupling between KK-gluon and a left-handed top quark. 
</parm> 
 
<modepick name="ExtraDimensionsG*:KKintMode" default="0" min="0" max="2"> 
Choice of full <ei>g^*/KK-gluon^*</ei> structure or not in relevant 
processes. 
<option value="0">full <ei>g^*/KK-gluon^*</ei> structure, with 
interference included.</option> 
<option value="1">only pure <ei>gluon_{SM}</ei> contribution.</option> 
<option value="2">only pure <ei>gluon_{KK}</ei> contribution.</option> 
</modepick> 
 
<h3>TeV^-1 Sized Extra Dimension, production processes</h3> 
 
This section contains a processes involving the production 
of electroweak KK gauge bosons, i.e. <ei>gamma_{KK}/Z_{KK}</ei>, 
in one TeV^-1 sized extra dimension. The process is described 
in <ref>Bel10</ref> and allows for individual final states to be 
specified. 
 
<flag name="ExtraDimensionsTEV:ffbar2ddbar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; d dbar </ei>, 
Code 5061. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2uubar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; u ubar </ei>, 
Code 5062. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2ssbar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; s sbar </ei>, 
Code 5063. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2ccbar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; c cbar </ei>, 
Code 5064. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2bbbar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; b bbar </ei>, 
Code 5065. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2ttbar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; t tbar </ei>, 
Code 5066. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2e+e-" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; e+ e- </ei>, 
Code 5071. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2nuenuebar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; nue nuebar </ei>, 
Code 5072. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2mu+mu-" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; mu+ mu- </ei>, 
Code 5073. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2numunumubar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; numu numubar </ei>, 
Code 5074. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2tau+tau-" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; tau+ tau- </ei>, 
Code 5075. 
</flag> 
 
<flag name="ExtraDimensionsTEV:ffbar2nutaunutaubar" default="off"> 
Scatterings <ei>f fbar &rarr; (gamma_{KK}/Z_{KK}) &rarr; nutau nutaubar </ei>, 
Code 5076. 
</flag> 
 
<h3>TeV^-1 Sized Extra Dimension, parameters</h3> 
 
Irrespective of the parameter options used, the particle produced, 
<ei>gamma_{KK}/Z_{KK}</ei>, will always be assigned code 5000023. 
 
<modepick name="ExtraDimensionsTEV:gmZmode" default="3" min="0" max="5"> 
Choice of full <ei>gamma_{KK}/Z_{KK}</ei> structure or not in relevant 
processes. 
<option value="0">full <ei>gamma_{SM}/Z_{SM}</ei> structure, with 
interference included.</option> 
<option value="1">only pure <ei>gamma_{SM}</ei> contribution.</option> 
<option value="2">only pure <ei>Z_{SM}</ei> contribution.</option> 
<option value="3">full <ei>gamma_{KK}/Z_{KK}</ei> structure, with 
interference included.</option> 
<option value="4">only pure <ei>gamma_{KK}</ei> contribution, with 
SM interference included.</option> 
<option value="5">only pure <ei>Z_{KK}</ei> contribution, with SM 
interference included.</option> 
</modepick> 
 
<modeopen name="ExtraDimensionsTEV:nMax" default="10" min="1" max="100"> 
The number of included KK excitations. 
</modeopen> 
 
<parm name="ExtraDimensionsTEV:mStar" default="4000.0" min="1000.0"> 
The KK mass <ei>m^*</ei>, given by the inverse of the single extra 
dimension radius. 
</parm> 
 
<h3>Large Extra Dimensions, production processes</h3> 
 
The LED graviton, where the KK-modes normally are summed and do not 
give rise to phenomena individually, is assigned PDG code 5000039. 
The graviton emission and virtual graviton exchange processes use 
the same implementation as the corresponding unparticle processes, 
which are all described in <ref>Ask10</ref>. It is also possible to 
generate monojet events from scalar graviton emission as described 
in <ref>Azu05</ref>, by turning on the option <ei>GravScalar</ei>. 
 
<p/> 
<ei>Note:</ei> As discussed in <ref>Ask09</ref>, for the graviton or 
unparticle emission processes the underlying Breit-Wigner mass 
distribution should be matched to the graviton mass spectrum in order 
to achieve an optimal MC efficiency. 
 
<p/> 
The following lowest order graviton emission processes are available. 
 
<flag name="ExtraDimensionsLED:monojet" default="off"> 
Common switch for the group of lowest-order <ei>G jet</ei> emission 
processes, i.e. the three ones below. 
</flag> 
 
<flag name="ExtraDimensionsLED:gg2Gg" default="off"> 
Scatterings <ei>g g &rarr; G g</ei>. 
Code 5021. 
</flag> 
 
<flag name="ExtraDimensionsLED:qg2Gq" default="off"> 
Scatterings <ei>q g &rarr; G q</ei>. 
Code 5022. 
</flag> 
 
<flag name="ExtraDimensionsLED:qqbar2Gg" default="off"> 
Scatterings <ei>q qbar &rarr; G g</ei>. 
Code 5023. 
</flag> 
 
<flag name="ExtraDimensionsLED:ffbar2GZ" default="off"> 
Scatterings <ei>f fbar &rarr; G Z</ei>. 
Code 5024. 
</flag> 
 
<flag name="ExtraDimensionsLED:ffbar2Ggamma" default="off"> 
Scatterings <ei>f fbar &rarr; G gamma</ei>. This process corresponds 
to the photon limit of the <ei>G Z</ei> process, as described in 
<ref>Ask09</ref>. 
Code 5025. 
</flag> 
 
<p/> 
The following LED processes with virtual graviton exchange are 
available. 
 
<flag name="ExtraDimensionsLED:ffbar2gammagamma" default="off"> 
Scatterings <ei>f fbar &rarr; (LED G*) &rarr; gamma gamma</ei>. If the 
graviton contribution is zero, the results corresponds to the 
SM contribution, i.e. equivalent to 
<code>PromptPhoton:ffbar2gammagamma</code>. 
Code 5026. 
</flag> 
 
<flag name="ExtraDimensionsLED:gg2gammagamma" default="off"> 
Scatterings <ei>g g &rarr; (LED G*) &rarr; gamma gamma</ei>. 
Code 5027. 
</flag> 
 
<flag name="ExtraDimensionsLED:ffbar2llbar" default="off"> 
Scatterings <ei>f fbar &rarr; (LED G*) &rarr; l l </ei>, where 
<ei>l</ei> is a charged lepton. If the graviton contribution 
is zero, the results corresponds to the SM contribution, i.e. 
similar to <code>WeakSingleBoson:ffbar2gmZ</code>. Does not 
include t-channel amplitude relevant for e^+e^- to e^+e^- 
and no K-factor is used. 
Code 5028. 
</flag> 
 
<flag name="ExtraDimensionsLED:gg2llbar" default="off"> 
Scatterings <ei>g g &rarr; (LED G*) &rarr; l l</ei>. 
Code 5029. 
</flag> 
 
<p/> 
Dijet production including graviton exchange is also available, using 
the same effective theory approach as the LED G exchange processes 
above or including more detailed amplitudes in accordance with 
<ref>Fra11</ref>. In case of the latter, the value of <ei>LambdaT</ei> 
is used as the value of the cut-off scale <ei>Lambda</ei>. For this 
reason the dijet processes only relates to the LED model and no 
unparticle versions are available. The processes are grouped together 
like their <ei>HardQCD</ei> equivalents and should therefore converge 
to the same results in the limit of an insignificant graviton 
contribution. 
 
<p/> 
<ei>Warning:</ei> These LED dijets processes are still being validated. 
 
<flag name="ExtraDimensionsLED:dijets" default="off"> 
Common switch for the group of lowest-order <ei>jet jet</ei> 
production processes with graviton exchange, i.e. the six ones 
below. 
</flag> 
 
<flag name="ExtraDimensionsLED:gg2DJgg" default="off"> 
Scatterings <ei>g g &rarr; (LED G*) &rarr; g g</ei>. 
Code 5030. 
</flag> 
 
<flag name="ExtraDimensionsLED:gg2DJqqbar" default="off"> 
Scatterings <ei>g g &rarr; (LED G*) &rarr; q qbar</ei>. Number of 
outgoing flavours specified by <ei>nQuarkNew</ei> parameter 
below. 
Code 5031. 
</flag> 
 
<flag name="ExtraDimensionsLED:qg2DJqg" default="off"> 
Scatterings <ei>q g &rarr; (LED G*) &rarr; q g</ei> and 
<ei>qbar g &rarr; (LED G*) &rarr; qbar g</ei>. 
Code 5032. 
</flag> 
 
<flag name="ExtraDimensionsLED:qq2DJqq" default="off"> 
Scatterings <ei>q q(bar)' &rarr; (LED G*) &rarr; q q(bar)'</ei>. 
Including <ei>q</ei> and <ei>qbar</ei> of same or different 
flavours, but the outgoing flavours equals the incoming ones. 
Code 5033. 
</flag> 
 
<flag name="ExtraDimensionsLED:qqbar2DJgg" default="off"> 
Scatterings <ei>q qbar &rarr; (LED G*) &rarr; g g</ei>. 
Code 5034. 
</flag> 
 
<flag name="ExtraDimensionsLED:qqbar2DJqqbarNew" default="off"> 
Scatterings <ei>q qbar &rarr; (LED G*) &rarr; q' qbar'</ei>. Number of 
outgoing flavours specified by <ei>nQuarkNew</ei> parameter below. 
Code 5035. 
</flag> 
 
<h3>Large Extra Dimensions, parameters</h3> 
 
<flag name="ExtraDimensionsLED:GravScalar" default="off"> 
Allow the monojet processes to produce scalar graviton emission 
instead of the default tensor one. The scalar option is according 
to the processes described in <ref>Azu05</ref> and includes two 
coupling constants below. 
</flag> 
 
<modeopen name="ExtraDimensionsLED:n" default="2" min="1"> 
Number of extra dimensions. 
</modeopen> 
 
<parm name="ExtraDimensionsLED:MD" default="2000." min="100.0"> 
Fundamental scale of gravity in <ei>D = 4 + n</ei> dimensions. 
</parm> 
 
<parm name="ExtraDimensionsLED:LambdaT" default="2000." min="100.0"> 
Ultraviolet cutoff parameter for the virtual graviton exchange processes. 
</parm> 
 
<modepick name="ExtraDimensionsLED:NegInt" default="0" min="0" max="1"> 
Allows to change sign of the interference terms in the graviton exchange 
processes, common in connection to using the <ei>Hewett</ei> convention 
<ref>Hew99</ref>. 
<option value="0">1</option> 
<option value="1">-1</option> 
</modepick> 
 
<modepick name="ExtraDimensionsLED:CutOffMode" default="0" min="0" max="3"> 
Options for when the hard scale of the process (e.g. <ei>sHat</ei>) 
approaches or exceed the scale of validity of the low energy effective 
theory (e.g. <ei>M_D</ei>). <ei>Note:</ei> Option 1 only concerns the 
graviton emission processes and the form factor is currently not available 
for the scalar graviton processes. 
<option value="0">Do nothing, i.e. all values of <ei>sHat</ei> contribute. 
</option> 
<option value="1">Truncate contributing <ei>sHat</ei> region 
(<ref>Ask09</ref>).</option> 
<option value="2">Form factor, using <ei>mu = renormScale2</ei> .</option> 
<option value="3">Form factor, using <ei>mu = E_jet</ei>.</option> 
</modepick> 
 
<parm name="ExtraDimensionsLED:t" default="1." min="0.001"> 
Form factor parameter. 
</parm> 
 
<parm name="ExtraDimensionsLED:g" default="1.0" min="0.0"> 
Coupling related to scalar graviton emission. 
</parm> 
 
<parm name="ExtraDimensionsLED:c" default="1.0" min="0.0"> 
Coupling related to scalar graviton emission. 
</parm> 
 
<modeopen name="ExtraDimensionsLED:nQuarkNew" default="3" min="0" max="5"> 
Number of allowed outgoing new quark flavours in the above 
<ei>q qbar &rarr; (LED G*) &rarr; q' qbar'</ei> and 
<ei>g g &rarr; (LED G*) &rarr; q' qbar'</ei> 
processes. Similar to <ei>HardQCD:nQuarkNew</ei> for the QCD processes. 
</modeopen> 
 
<modeopen name="ExtraDimensionsLED:opMode" default="0" min="0" max="1"> 
Options to specify <ei>S</ei> function for LED dijet amplitudes. 
<option value="0">Use detailed amplitude, as described in <ref>Fra11</ref>. 
</option> 
<option value="1">Use conventional <ei>LambdaT</ei> parametrization, 
like the other LED processes.</option> 
</modeopen> 
 
<h3>Unparticles, production processes</h3> 
 
As mentioned above, the similar unparticle and graviton processes 
share the same implementations. The unparticle processes, however, 
only use the dedicated unparticle parameters below. The unparticle 
is also assigned the PDG code 5000039 and is therefore called 
<ei>Graviton</ei> in the event record. The graviton and unparticle 
emission as well as virtual graviton and unparticle exchange processes 
are described in <ref>Ask10</ref>. 
 
<p/> 
<ei>Note:</ei> As discussed in <ref>Ask09</ref>, for the graviton or 
unparticle emission processes the underlying Breit-Wigner mass 
distribution should be matched to the graviton mass spectrum in order 
to achieve an optimal MC efficiency. 
 
<p/> 
The following unparticle emission processes are available. 
 
<flag name="ExtraDimensionsUnpart:monojet" default="off"> 
Common switch for the group of lowest-order <ei>U jet</ei> emission 
processes, i.e. the three ones below. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:gg2Ug" default="off"> 
Scatterings <ei>g g &rarr; U g</ei>. 
Code 5045. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:qg2Uq" default="off"> 
Scatterings <ei>q g &rarr; U q</ei>. 
Code 5046. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:qqbar2Ug" default="off"> 
Scatterings <ei>q qbar &rarr; U g</ei>. 
Code 5047. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:ffbar2UZ" default="off"> 
Scatterings <ei>f fbar &rarr; U Z</ei>. 
Code 5041. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:ffbar2Ugamma" default="off"> 
Scatterings <ei>f fbar &rarr; U gamma</ei>. This process corresponds 
to the photon limit of the <ei>U Z</ei> process, as described in 
<ref>Ask09</ref>. 
Code 5042. 
</flag> 
 
<p/> 
The following processes with virtual unparticle exchange are available. 
 
<flag name="ExtraDimensionsUnpart:ffbar2gammagamma" default="off"> 
Scatterings <ei>f fbar &rarr; (U*) &rarr; gamma gamma</ei>. If the unparticle 
contribution is zero in the spin-2 case, the results corresponds to 
the SM contribution, i.e. equivalent to 
<code>PromptPhoton:ffbar2gammagamma</code>. 
Code 5043. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:gg2gammagamma" default="off"> 
Scatterings <ei>g g &rarr; (U*) &rarr; gamma gamma</ei>. 
Code 5044. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:ffbar2llbar" default="off"> 
Scatterings <ei>f fbar &rarr; (U*) &rarr; l lbar </ei>, where 
<ei>l</ei> is a charged lepton. If the unparticle contribution 
is zero, the results corresponds to the SM contribution, i.e. 
similar to <code>WeakSingleBoson:ffbar2gmZ</code>. Does not 
include t-channel amplitude relevant for e^+e^- to e^+e^- 
and no K-factor is used. 
Code 5048. 
</flag> 
 
<flag name="ExtraDimensionsUnpart:gg2llbar" default="off"> 
Scatterings <ei>g g &rarr; (U*) &rarr; l lbar</ei>. 
Code 5049. 
</flag> 
 
<h3>Unparticles, parameters</h3> 
 
<modeopen name="ExtraDimensionsUnpart:spinU" default="2" min="0" max="2"> 
Unparticle spin. 
</modeopen> 
 
<parm name="ExtraDimensionsUnpart:dU" default="1.4" min="1.0"> 
Scale dimension parameter. 
</parm> 
 
<parm name="ExtraDimensionsUnpart:LambdaU" default="2000." min="100.0"> 
Unparticle renormalization scale. 
</parm> 
 
<parm name="ExtraDimensionsUnpart:lambda" default="1.0" min="0.0"> 
Unparticle coupling to the SM fields. 
</parm> 
 
<parm name="ExtraDimensionsUnpart:ratio" default="1.0" min="1.0" max="1.0"> 
Ratio, <ei>lambda'/lambda</ei>, between the two possible coupling constants 
of the spin-2 ME. <b>Warning:</b> A <ei>ratio</ei> value different from one 
give rise to an IR divergence which makes the event generation very slow, so 
this values is fixed to <ei>ratio = 1</ei> for the moment. 
</parm> 
 
<modepick name="ExtraDimensionsUnpart:CutOffMode" default="0" min="0" max="1"> 
Options for when the hard scale of the process (e.g. <ei>sHat</ei>) 
approaches or exceed the scale of validity of the low energy effective 
theory (<ei>Lambda_U</ei>). This mode only concerns the unparticle 
emission processes. 
<option value="0">Do nothing, i.e. all values of <ei>sHat</ei> 
contribute.</option> 
<option value="1">Truncate contributing <ei>sHat</ei> region 
(<ref>Ask09</ref>).</option> 
</modepick> 
 
<modepick name="ExtraDimensionsUnpart:gXX" default="0" min="0" max="2"> 
Chiral unparticle couplings, <ei>gXX = gLL = gRR</ei>. Only relevant 
for lepton production from spin-1 unparticle exchange. 
<option value="0">1</option> 
<option value="1">-1</option> 
<option value="2">0</option> 
</modepick> 
 
<modepick name="ExtraDimensionsUnpart:gXY" default="0" min="0" max="2"> 
Chiral unparticle couplings, <ei>gXY = gLR = gRL</ei>. Only relevant 
for lepton production from spin-1 unparticle exchange. 
<option value="0">1</option> 
<option value="1">-1</option> 
<option value="2">0</option> 
</modepick> 
 
</chapter> 
 
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