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<title>Extra-Dimensional Processes</title>
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<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 [<a href="Bibliography.html" target="page">Bij01</a>] and the KKgluon* process in [<a href="Bibliography.html" target="page">Ask11</a>].
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 <i>G^*</i> production.
<p/><code>flag </code><strong> ExtraDimensionsG*:all </strong>
(<code>default = <strong>off</strong></code>)<br/>
Common switch for the group of lowest-order <i>G^*</i> production
processes, i.e. the two ones below.
<p/><code>flag </code><strong> ExtraDimensionsG*:gg2G* </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → G^*</i>.
Code 5001.
<p/><code>flag </code><strong> ExtraDimensionsG*:ffbar2G* </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → G^*</i>.
Code 5002.
<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-<i>pT</i> tail of <i>G^*</i> 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.
<p/><code>flag </code><strong> ExtraDimensionsG*:gg2G*g </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → G^* g</i>.
Code 5003.
<p/><code>flag </code><strong> ExtraDimensionsG*:qg2G*q </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q g → G^* q</i>.
Code 5004.
<p/><code>flag </code><strong> ExtraDimensionsG*:qqbar2G*g </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → G^* g</i>.
Code 5005.
<p/>
There is also one process for the production of a gluon resonance.
<p/><code>flag </code><strong> ExtraDimensionsG*:qqbar2KKgluon* </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → g^*/KKgluon^*</i>.
Code 5006.
<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 <i>kappaMG</i> follows the conventions in [<a href="Bibliography.html" target="page">Bij01</a>],
where as the flavour dependent couplings follow the conventions used in
[<a href="Bibliography.html" target="page">Dav01</a>].
<p/><code>flag </code><strong> ExtraDimensionsG*:SMinBulk </strong>
(<code>default = <strong>off</strong></code>)<br/>
Parameter to choose between the two scenarios:
<i>off</i>, SM on the TeV brane (common <i>kappaMG</i> coupling);
<i>on</i>, SM in the ED bulk (flavour dependent couplings).
This parameter is only relevant for the lowest-order graviton
(<i>G*</i>) processes, where as the first-order processes
corresponds to the <i>off</i> scenario.
<p/><code>flag </code><strong> ExtraDimensionsG*:VLVL </strong>
(<code>default = <strong>on</strong></code>)<br/>
Parameter to specify Z/W coupling scenario:
<i>off</i>, usual Z/W boson couplings;
<i>on</i>, coupling only to longitudinal Z/W bosons.
In both cases the <i>GZZ</i> and <i>GWW</i> values are used
and this parameter is only relevant when <i>SMinBulk = on</i>.
The formulas for longitudinal bosons should be appropriate up to
<i>O(m_V/E_V)</i> corrections.
<p/><code>parm </code><strong> ExtraDimensionsG*:kappaMG </strong>
(<code>default = <strong>0.054</strong></code>; <code>minimum = 0.0</code>)<br/>
dimensionless coupling, which enters quadratically in all on-shell
partial widths of the <i>G^*</i>. Is
<i>kappa m_G* = sqrt(2) x_1 k / Mbar_Pl</i>,
where <i>x_1 = 3.83</i> is the first zero of the <i>J_1</i> Bessel
function and <i>Mbar_Pl</i> is the modified Planck mass.
In width and cross section calculations, <i>kappa</i> is fixed by
the on-shell <i>G^*</i> mass and <i>kappaMG</i>, i.e.
<i>kappaMG</i> scales with the off-shell <i>G^*</i> mass.
<p/><code>parm </code><strong> ExtraDimensionsG*:Gll </strong>
(<code>default = <strong>0.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and leptons.
<p/><code>parm </code><strong> ExtraDimensionsG*:Gqq </strong>
(<code>default = <strong>0.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and light quarks.
<p/><code>parm </code><strong> ExtraDimensionsG*:Gbb </strong>
(<code>default = <strong>0.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and bottom quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:Gtt </strong>
(<code>default = <strong>0.001</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and top quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:Ggg </strong>
(<code>default = <strong>0.000013</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and gluon.
<p/><code>parm </code><strong> ExtraDimensionsG*:Ggmgm </strong>
(<code>default = <strong>0.000013</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and gamma.
<p/><code>parm </code><strong> ExtraDimensionsG*:GZZ </strong>
(<code>default = <strong>0.001</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and Z boson.
<p/><code>parm </code><strong> ExtraDimensionsG*:GWW </strong>
(<code>default = <strong>0.001</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and W boson.
<p/><code>parm </code><strong> ExtraDimensionsG*:Ghh </strong>
(<code>default = <strong>0.001</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling between graviton and Higgs bosons.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgqR </strong>
(<code>default = <strong>-0.2</strong></code>)<br/>
Coupling between KK-gluon and a right-handed light quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgqL </strong>
(<code>default = <strong>-0.2</strong></code>)<br/>
Coupling between KK-gluon and a left-handed light quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgbR </strong>
(<code>default = <strong>-0.2</strong></code>)<br/>
Coupling between KK-gluon and a right-handed bottom quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgbL </strong>
(<code>default = <strong>1.0</strong></code>)<br/>
Coupling between KK-gluon and a left-handed bottom quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgtR </strong>
(<code>default = <strong>4.0</strong></code>)<br/>
Coupling between KK-gluon and a right-handed top quark.
<p/><code>parm </code><strong> ExtraDimensionsG*:KKgtL </strong>
(<code>default = <strong>1.0</strong></code>)<br/>
Coupling between KK-gluon and a left-handed top quark.
<p/><code>mode </code><strong> ExtraDimensionsG*:KKintMode </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 2</code>)<br/>
Choice of full <i>g^*/KK-gluon^*</i> structure or not in relevant
processes.
<br/><code>option </code><strong> 0</strong> : full <i>g^*/KK-gluon^*</i> structure, with
interference included.
<br/><code>option </code><strong> 1</strong> : only pure <i>gluon_{SM}</i> contribution.
<br/><code>option </code><strong> 2</strong> : only pure <i>gluon_{KK}</i> contribution.
<h3>TeV^-1 Sized Extra Dimension, production processes</h3>
This section contains a processes involving the production
of electroweak KK gauge bosons, i.e. <i>gamma_{KK}/Z_{KK}</i>,
in one TeV^-1 sized extra dimension. The process is described
in [<a href="Bibliography.html" target="page">Bel10</a>] and allows for individual final states to be
specified.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2ddbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → d dbar </i>,
Code 5061.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2uubar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → u ubar </i>,
Code 5062.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2ssbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → s sbar </i>,
Code 5063.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2ccbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → c cbar </i>,
Code 5064.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2bbbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → b bbar </i>,
Code 5065.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2ttbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → t tbar </i>,
Code 5066.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2e+e- </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → e+ e- </i>,
Code 5071.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2nuenuebar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → nue nuebar </i>,
Code 5072.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2mu+mu- </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → mu+ mu- </i>,
Code 5073.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2numunumubar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → numu numubar </i>,
Code 5074.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2tau+tau- </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → tau+ tau- </i>,
Code 5075.
<p/><code>flag </code><strong> ExtraDimensionsTEV:ffbar2nutaunutaubar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (gamma_{KK}/Z_{KK}) → nutau nutaubar </i>,
Code 5076.
<h3>TeV^-1 Sized Extra Dimension, parameters</h3>
Irrespective of the parameter options used, the particle produced,
<i>gamma_{KK}/Z_{KK}</i>, will always be assigned code 5000023.
<p/><code>mode </code><strong> ExtraDimensionsTEV:gmZmode </strong>
(<code>default = <strong>3</strong></code>; <code>minimum = 0</code>; <code>maximum = 5</code>)<br/>
Choice of full <i>gamma_{KK}/Z_{KK}</i> structure or not in relevant
processes.
<br/><code>option </code><strong> 0</strong> : full <i>gamma_{SM}/Z_{SM}</i> structure, with
interference included.
<br/><code>option </code><strong> 1</strong> : only pure <i>gamma_{SM}</i> contribution.
<br/><code>option </code><strong> 2</strong> : only pure <i>Z_{SM}</i> contribution.
<br/><code>option </code><strong> 3</strong> : full <i>gamma_{KK}/Z_{KK}</i> structure, with
interference included.
<br/><code>option </code><strong> 4</strong> : only pure <i>gamma_{KK}</i> contribution, with
SM interference included.
<br/><code>option </code><strong> 5</strong> : only pure <i>Z_{KK}</i> contribution, with SM
interference included.
<p/><code>parm </code><strong> ExtraDimensionsTEV:nMax </strong>
(<code>default = <strong>10</strong></code>; <code>minimum = 1</code>; <code>maximum = 100</code>)<br/>
The number of included KK excitations.
<p/><code>parm </code><strong> ExtraDimensionsTEV:mStar </strong>
(<code>default = <strong>4000.0</strong></code>; <code>minimum = 1000.0</code>)<br/>
The KK mass <i>m^*</i>, given by the inverse of the single extra
dimension radius.
<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 [<a href="Bibliography.html" target="page">Ask10</a>]. It is also possible to
generate monojet events from scalar graviton emission as described
in [<a href="Bibliography.html" target="page">Azu05</a>], by turning on the option <i>GravScalar</i>.
<p/>
<i>Note:</i> As discussed in [<a href="Bibliography.html" target="page">Ask09</a>], 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.
<p/><code>flag </code><strong> ExtraDimensionsLED:monojet </strong>
(<code>default = <strong>off</strong></code>)<br/>
Common switch for the group of lowest-order <i>G jet</i> emission
processes, i.e. the three ones below.
<p/><code>flag </code><strong> ExtraDimensionsLED:gg2Gg </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → G g</i>.
Code 5021.
<p/><code>flag </code><strong> ExtraDimensionsLED:qg2Gq </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q g → G q</i>.
Code 5022.
<p/><code>flag </code><strong> ExtraDimensionsLED:qqbar2Gg </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → G g</i>.
Code 5023.
<p/><code>flag </code><strong> ExtraDimensionsLED:ffbar2GZ </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → G Z</i>.
Code 5024.
<p/><code>flag </code><strong> ExtraDimensionsLED:ffbar2Ggamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → G gamma</i>. This process corresponds
to the photon limit of the <i>G Z</i> process, as described in
[<a href="Bibliography.html" target="page">Ask09</a>].
Code 5025.
<p/>
The following LED processes with virtual graviton exchange are
available.
<p/><code>flag </code><strong> ExtraDimensionsLED:ffbar2gammagamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (LED G*) → gamma gamma</i>. If the
graviton contribution is zero, the results corresponds to the
SM contribution, i.e. equivalent to
<code>PromptPhoton:ffbar2gammagamma</code>.
Code 5026.
<p/><code>flag </code><strong> ExtraDimensionsLED:gg2gammagamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (LED G*) → gamma gamma</i>.
Code 5027.
<p/><code>flag </code><strong> ExtraDimensionsLED:ffbar2llbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (LED G*) → l l </i>, where
<i>l</i> 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.
<p/><code>flag </code><strong> ExtraDimensionsLED:gg2llbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (LED G*) → l l</i>.
Code 5029.
<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
[<a href="Bibliography.html" target="page">Fra11</a>]. In case of the latter, the value of <i>LambdaT</i>
is used as the value of the cut-off scale <i>Lambda</i>. 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 <i>HardQCD</i> equivalents and should therefore converge
to the same results in the limit of an insignificant graviton
contribution.
<p/>
<i>Warning:</i> These LED dijets processes are still being validated.
<p/><code>flag </code><strong> ExtraDimensionsLED:dijets </strong>
(<code>default = <strong>off</strong></code>)<br/>
Common switch for the group of lowest-order <i>jet jet</i>
production processes with graviton exchange, i.e. the six ones
below.
<p/><code>flag </code><strong> ExtraDimensionsLED:gg2DJgg </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (LED G*) → g g</i>.
Code 5030.
<p/><code>flag </code><strong> ExtraDimensionsLED:gg2DJqqbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (LED G*) → q qbar</i>. Number of
outgoing flavours specified by <i>nQuarkNew</i> parameter
below.
Code 5031.
<p/><code>flag </code><strong> ExtraDimensionsLED:qg2DJqg </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q g → (LED G*) → q g</i> and
<i>qbar g → (LED G*) → qbar g</i>.
Code 5032.
<p/><code>flag </code><strong> ExtraDimensionsLED:qq2DJqq </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q q(bar)' → (LED G*) → q q(bar)'</i>.
Including <i>q</i> and <i>qbar</i> of same or different
flavours, but the outgoing flavours equals the incoming ones.
Code 5033.
<p/><code>flag </code><strong> ExtraDimensionsLED:qqbar2DJgg </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → (LED G*) → g g</i>.
Code 5034.
<p/><code>flag </code><strong> ExtraDimensionsLED:qqbar2DJqqbarNew </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → (LED G*) → q' qbar'</i>. Number of
outgoing flavours specified by <i>nQuarkNew</i> parameter below.
Code 5035.
<h3>Large Extra Dimensions, parameters</h3>
<p/><code>flag </code><strong> ExtraDimensionsLED:GravScalar </strong>
(<code>default = <strong>off</strong></code>)<br/>
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 [<a href="Bibliography.html" target="page">Azu05</a>] and includes two
coupling constants below.
<p/><code>mode </code><strong> ExtraDimensionsLED:n </strong>
(<code>default = <strong>2</strong></code>; <code>minimum = 1</code>)<br/>
Number of extra dimensions.
<p/><code>parm </code><strong> ExtraDimensionsLED:MD </strong>
(<code>default = <strong>2000.</strong></code>; <code>minimum = 100.0</code>)<br/>
Fundamental scale of gravity in <i>D = 4 + n</i> dimensions.
<p/><code>parm </code><strong> ExtraDimensionsLED:LambdaT </strong>
(<code>default = <strong>2000.</strong></code>; <code>minimum = 100.0</code>)<br/>
Ultraviolet cutoff parameter for the virtual graviton exchange processes.
<p/><code>mode </code><strong> ExtraDimensionsLED:NegInt </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 1</code>)<br/>
Allows to change sign of the interference terms in the graviton exchange
processes, common in connection to using the <i>Hewett</i> convention
[<a href="Bibliography.html" target="page">Hew99</a>].
<br/><code>option </code><strong> 0</strong> : 1
<br/><code>option </code><strong> 1</strong> : -1
<p/><code>mode </code><strong> ExtraDimensionsLED:CutOffMode </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 3</code>)<br/>
Options for when the hard scale of the process (e.g. <i>sHat</i>)
approaches or exceed the scale of validity of the low energy effective
theory (e.g. <i>M_D</i>). <i>Note:</i> Option 1 only concerns the
graviton emission processes and the form factor is currently not available
for the scalar graviton processes.
<br/><code>option </code><strong> 0</strong> : Do nothing, i.e. all values of <i>sHat</i> contribute.
<br/><code>option </code><strong> 1</strong> : Truncate contributing <i>sHat</i> region
([<a href="Bibliography.html" target="page">Ask09</a>]).
<br/><code>option </code><strong> 2</strong> : Form factor, using <i>mu = renormScale2</i> .
<br/><code>option </code><strong> 3</strong> : Form factor, using <i>mu = E_jet</i>.
<p/><code>parm </code><strong> ExtraDimensionsLED:t </strong>
(<code>default = <strong>1.</strong></code>; <code>minimum = 0.001</code>)<br/>
Form factor parameter.
<p/><code>parm </code><strong> ExtraDimensionsLED:g </strong>
(<code>default = <strong>1.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling related to scalar graviton emission.
<p/><code>parm </code><strong> ExtraDimensionsLED:c </strong>
(<code>default = <strong>1.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Coupling related to scalar graviton emission.
<p/><code>mode </code><strong> ExtraDimensionsLED:nQuarkNew </strong>
(<code>default = <strong>3</strong></code>; <code>minimum = 0</code>; <code>maximum = 5</code>)<br/>
Number of allowed outgoing new quark flavours in the above
<i>q qbar → (LED G*) → q' qbar'</i> and
<i>g g → (LED G*) → q' qbar'</i>
processes. Similar to <i>HardQCD:nQuarkNew</i> for the QCD processes.
<p/><code>mode </code><strong> ExtraDimensionsLED:opMode </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 1</code>)<br/>
Options to specify <i>S</i> function for LED dijet amplitudes.
<br/><code>option </code><strong> 0</strong> : Use detailed amplitude, as described in [<a href="Bibliography.html" target="page">Fra11</a>].
<br/><code>option </code><strong> 1</strong> : Use conventional <i>LambdaT</i> parametrization,
like the other LED processes.
<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
<i>Graviton</i> in the event record. The graviton and unparticle
emission as well as virtual graviton and unparticle exchange processes
are described in [<a href="Bibliography.html" target="page">Ask10</a>].
<p/>
<i>Note:</i> As discussed in [<a href="Bibliography.html" target="page">Ask09</a>], 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.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:monojet </strong>
(<code>default = <strong>off</strong></code>)<br/>
Common switch for the group of lowest-order <i>U jet</i> emission
processes, i.e. the three ones below.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:gg2Ug </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → U g</i>.
Code 5045.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:qg2Uq </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q g → U q</i>.
Code 5046.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:qqbar2Ug </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>q qbar → U g</i>.
Code 5047.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:ffbar2UZ </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → U Z</i>.
Code 5041.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:ffbar2Ugamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → U gamma</i>. This process corresponds
to the photon limit of the <i>U Z</i> process, as described in
[<a href="Bibliography.html" target="page">Ask09</a>].
Code 5042.
<p/>
The following processes with virtual unparticle exchange are available.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:ffbar2gammagamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (U*) → gamma gamma</i>. 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.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:gg2gammagamma </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (U*) → gamma gamma</i>.
Code 5044.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:ffbar2llbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>f fbar → (U*) → l lbar </i>, where
<i>l</i> 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.
<p/><code>flag </code><strong> ExtraDimensionsUnpart:gg2llbar </strong>
(<code>default = <strong>off</strong></code>)<br/>
Scatterings <i>g g → (U*) → l lbar</i>.
Code 5049.
<h3>Unparticles, parameters</h3>
<p/><code>mode </code><strong> ExtraDimensionsUnpart:spinU </strong>
(<code>default = <strong>2</strong></code>; <code>minimum = 0</code>; <code>maximum = 2</code>)<br/>
Unparticle spin.
<p/><code>parm </code><strong> ExtraDimensionsUnpart:dU </strong>
(<code>default = <strong>1.4</strong></code>; <code>minimum = 1.0</code>)<br/>
Scale dimension parameter.
<p/><code>parm </code><strong> ExtraDimensionsUnpart:LambdaU </strong>
(<code>default = <strong>2000.</strong></code>; <code>minimum = 100.0</code>)<br/>
Unparticle renormalization scale.
<p/><code>parm </code><strong> ExtraDimensionsUnpart:lambda </strong>
(<code>default = <strong>1.0</strong></code>; <code>minimum = 0.0</code>)<br/>
Unparticle coupling to the SM fields.
<p/><code>parm </code><strong> ExtraDimensionsUnpart:ratio </strong>
(<code>default = <strong>1.0</strong></code>; <code>minimum = 1.0</code>; <code>maximum = 1.0</code>)<br/>
Ratio, <i>lambda'/lambda</i>, between the two possible coupling constants
of the spin-2 ME. <b>Warning:</b> A <i>ratio</i> value different from one
give rise to an IR divergence which makes the event generation very slow, so
this values is fixed to <i>ratio = 1</i> for the moment.
<p/><code>mode </code><strong> ExtraDimensionsUnpart:CutOffMode </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 1</code>)<br/>
Options for when the hard scale of the process (e.g. <i>sHat</i>)
approaches or exceed the scale of validity of the low energy effective
theory (<i>Lambda_U</i>). This mode only concerns the unparticle
emission processes.
<br/><code>option </code><strong> 0</strong> : Do nothing, i.e. all values of <i>sHat</i>
contribute.
<br/><code>option </code><strong> 1</strong> : Truncate contributing <i>sHat</i> region
([<a href="Bibliography.html" target="page">Ask09</a>]).
<p/><code>mode </code><strong> ExtraDimensionsUnpart:gXX </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 2</code>)<br/>
Chiral unparticle couplings, <i>gXX = gLL = gRR</i>. Only relevant
for lepton production from spin-1 unparticle exchange.
<br/><code>option </code><strong> 0</strong> : 1
<br/><code>option </code><strong> 1</strong> : -1
<br/><code>option </code><strong> 2</strong> : 0
<p/><code>mode </code><strong> ExtraDimensionsUnpart:gXY </strong>
(<code>default = <strong>0</strong></code>; <code>minimum = 0</code>; <code>maximum = 2</code>)<br/>
Chiral unparticle couplings, <i>gXY = gLR = gRL</i>. Only relevant
for lepton production from spin-1 unparticle exchange.
<br/><code>option </code><strong> 0</strong> : 1
<br/><code>option </code><strong> 1</strong> : -1
<br/><code>option </code><strong> 2</strong> : 0
</body>
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