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new release mokka-05-02 [message #378] Thu, 03 November 2005 07:47
musat
Messages: 57
Registered: February 2004
Dear Friends,

We are glad to announce a new Mokka release, the mokka-05-02. It's
available for download from the Mokka Web page at

http://polype.in2p3.fr/geant4/tesla/www/mokka/mokka.html


(from release notes:)


I. Range Cut per region implemented in the Calice Ecal
prototype
II. Bug fix in Geant 4 release 7.1.patch01

Thanks to Adrian Vogel from DESY (adrian.vogel@desy.de) we
now have the folowing new features in this Mokka release:
III. New Geometry Models "D13TDR", "D13Stahl", and "D13XStahl"
IV. Support for a Crossing Angle
V. New Physics List "PhysicsListNeutrons"
VI. New Commands for the Particle Gun
VII. Interface for Guinea Pig Files
VIII. Restructured Plugin Directory
IX. New Hooks for Plugins
X. Modified Definition of the Material "beam"
XI. Revision of the Makefiles
XII. A Comment on Possible Linking Problems
XIII. Miscellaneous
XIV. References

Thanks to Damien Grandjean from IRES, Strassbourg
(Damien.Grandjean@IReS.in2p3.fr), we now have the folowing
new feature in this Mokka release:

XV. New Geometry Models "D14" and "D14_CMOSVTX"
------------------------------------------------------------ ------------------
We recommend to compile and link this new Mokka release mokka-05-02
with Geant 4 release 7.1.patch01

New materials database "materials01" becomes the default. Users running a
local database should download this new database from the central MySQL
server (pollin1.in2p3.fr)

If you wish to use the physics list "LCPhys", make sure you compiled your
Geant 4 installation with the "G4BERTINI_KAON" preprocessor flag defined.
------------------------------------------------------------ ------------------


I. Range Cut per region implemented in the Calice Ecal prototype


Three separate regions were defined in the Ecal prototype (driver Proto03):
the Silicon Cells and Guard-Rings, the Tungsten and the G10 (PCB's).
One new command line option was defined for setting the Range Cut in
the Silicon: -C cut in mm. Three new steering init commands were introduced
to define the Range Cuts in the three regions mentionned above:

/Mokka/init/activeRangeCut - for the Silicon
/Mokka/init/radiatorRangeCut - for the Tungsten
/Mokka/init/pcbRangeCut - for the G10

This new feature is available with any Physics List.


II. Bug fix in Geant 4 release 7.1.patch01

While performing simulations at LLR - Ecole Polytechnique and at DESY,
it was noticed that while using Geant 4 release 7.0 and 7.1, Mokka sometimes
runs into an infinite loop, not processing any more events but still running.
Predrag Krstonosic from DESY saw that the cause of this trouble was
G4ChordFinder that had the end point of the chord set to (nan, nan, nan).
A series of tests was made to tune some parameters belonging, for example,
to G4FieldManager and G4ChordFinder, and to build G4ChordFinder with
different steppers (G4SimpleHeum, G4SimpleRunge, G4HelixSimpleRunge,
G4HelixExplicitEuler, G4HelixImplicitEuler). Every time, Mokka ended by
getting stuck.

According to John Apostolakis a solution was found and it was included in
Geant 4 release 7.1.patch01. Regarding the source of the problem, it has
been found in an electromagnetic process which caused the nan for the
direction. At LLR - Ecole Polytechnique a series of simulations were
performed with event files that caused the problem with previous Geant 4
releases, and it was noticed that with this last Geant 4 patch the infinite
loop didn't show up any more.


III. New Geometry Models "D13TDR", "D13Stahl", and "D13XStahl"

Three new geometry models named "D13TDR", "D13Stahl", and "D13XStahl" have
been added. They are derived from "D10" and offer an improved description of
the beam tube, the overall forward region and the magnetic fields. "D13TDR"
models the forward region as it was described in the TESLA Technical Design
Report [1] (featuring the LAT and LCAL forward detectors and a final focus
length L* of 3.00 m), "D13Stahl" follows a proposal made by Achim Stahl et
al. (LC-DET-2004-034) [2] (featuring the LumCal and BeamCal detectors and a
final focus length L* of 4.05 m), and "D13XStahl" is equal to the second
except that it has a beam crossing angle of 20 mrad.

The models make use of several new geometry drivers which support a crossing
angle, introduce the final focus quadrupoles, and are able to model the
solenoid field from a field map, including an optional "detector-integrated
dipole" (DID). Apart from the detector components which have simply been
inherited from "D10", the models introduce a couple of new subdetectors which
are shown below. Besides that, they use the subdetectors "ftd01" instead of
"ftd00" and "vxd01" instead of "vxd00".

tubeX00TDR, tubeX00Stahl, tubeX00XStahl (using the driver tubeX00)

The beam tube and the contained vacuum from the interaction point up to a
distance of z = 10 m.

maskX00TDR, maskX00Stahl, maskX00XStahl (using the driver maskX00)

The whole mask of the forward region, including a graphite absorber, the
main support tube, roughly-modelled electronics and vacuum installations,
the final focus magnets with their cryostats, and - for the time being -
also the forward calorimeters, implemented as non-sensitive solid blocks
of material. Note that the models do not make use of the more detailed
"LumiCalS" which was introduced with the model "D12".

fieldX00TDR, fieldX00Stahl, fieldX00XStahl (using the driver fieldX00)

The fields of the final focus quadrupoles as well as the main solenoid,
thereby using the solenoid field maps which have recently been published
by the SLAC magnet group (see the web page of the Beam Delivery Meeting,
2005-07-26) [3]. The superimposed DID field is currently not enabled, but
it is supported by the geometry driver and can be switched on by changing
one flag in the geometry database.

yoke01TDR, yoke01Stahl, yoke01XStahl (using the driver yoke01)

Modifications of the existing subdetector "yoke00", with an octagonal
shape and an adjusted inner diameter of the endcaps.

tpc05 (using the driver tpc03)

A modification of the existing subdetector tpc04, now reading the chamber
gas from its database and fixing a geometry overlap problem with the TPC
endplates. Together with this subdetector, a few gas mixtures have been
added to the Mokka materials database: "TDR_gas" (93% Ar, 5% CH4,
2% CO2), "P5_gas" (95% Ar, 5% CH4), and "P10_gas" (90% Ar, 10% CH4). The
chamber modelled by "tpc05" is currently filled with TDR gas.


IV. Support for a Crossing Angle

Since there is now a geometry model with a crossing angle available, a new
steering command has been added:

/Mokka/init/lorentzTransformationAngle

Sets the angle which is used to transform the momenta of all primary
particles (both from the particle gun and from generator files) from the
centre-of-mass frame (in which they are usually generated) into the
laboratory frame (in which they are detected). Parameters are a scalar
(initial value 0) and an optional unit (default mrad). Be aware that the
given angle is the angle between the incoming beams and the z-axis, i. e.
half the crossing angle between the two beams. This command is only
available in the pre-initialisation state, i. e. it may only appear in
your steering file.

The Lorentz transformation which will be applied acts in the following way:
If you select the angle stated above and then shoot a relativistic particle
straight in the z-direction (for example with the particle gun), its momentum
will actually have the given angle with respect to the z-axis. The energy of
the particle is slightly increased so that the simulated centre-of-mass
energy stays the same, because a small fraction of the particle energy gets
used up in order to boost the centre-of-mass frame with respect to the
laboratory frame. Particles flying in other directions and non-relativistic
particles will be transformed accordingly. Note that the positions of the
vertices will not be Lorentz-transformed.

Please note that it's your own responsibility to make sure you set the
transformation angle correctly - the angle will _not_ be set automatically
when the geometry gets constructed. You may want to select a model with a
head-on detector geometry and still use a small crossing angle such as
2 mrad, in which case there is no need for a second beam tube inside the
interaction region. You may also have a particle generator which already
accounts for the crossing angle - in that case no further transformation will
be needed.

V. New Physics List "PhysicsListNeutrons"

A new physics list named "PhysicsListNeutrons" has been added. It is a
variant of the existing "PhysicsList", intended for simulations including
neutrons (from background reactions). PhysicsListNeutrons enables
gamma-nuclear processes (i. e. neutron production in nuclear reactions) and
uses high-precision models for low-energy neutrons.

You can select PhysicsListNeutrons with the command
"/Mokka/init/physicsListName PhysicsListNeutrons" in your Mokka steering
file. Please note that you need to have the environment variable
"NeutronHPCrossSections" set correctly _at runtime_ - otherwise, Mokka will
be aborted at startup. You should also be aware that the startup of Mokka
will take _much_ longer than usual when you use PhysicsListNeutrons.

The Linear Collider Physics List "LCPhys" by Dennis Wright also enables
gamma-nuclear processes, but up to now it uses neutron models which become
rather poor at low energies (below approximately 20 MeV). LCPhys might
include the high-precision models at some time in the future - as soon as
this happens, PhysicsListNeutrons should be considered obsolete. For more
information on physics lists, have a look at the Geant 4 Hadronic Physics
Home Page [4] by Hans-Peter Wellisch, particularly the section on linear
collider neutron fluxes.

VI. New Commands for the Particle Gun

The commands to control the behaviour of the particle gun have been modified
and partially extended. The previously existing commands "/generator/scan",
"/generator/randomDirections", "/generator/gaussgun", and
"/generator/gaussgun/momentum" have been replaced by the following:

/gun/positionStep

Sets a step by which the position of the gun will be changed after each
shot. The parameters are an optional three vector (default 0 0 0) with an
optional unit (default cm). This command corresponds to the previous
"/generator/scan".

/gun/positionSmearing

Sets the uncertainties (i. e. gaussian sigmas) by which the three
coordinates of the position of the gun will be smeared in each shot. The
parameters are an optional three vector (default 0 0 0) with an optional
unit (default cm). Together with "/gun/position", this command
corresponds to the previous "/generator/gaussgun".

/gun/thetaStep

Sets a step by which the polar angle of the gun will be changed after
each shot. The parameters are an optional scalar (default 0) with an
optional unit (default deg). This functionality is new. Please note that
the polar angle will get stuck if it reaches the boundaries 0 deg or
180 deg.

/gun/thetaSmearing

Sets an uncertainty (see "/gun/directionSmearingMode") by which the polar
angle of the gun will be smeared in each shot. The parameters are an
optional scalar (default 0) with an optional unit (default deg). Together
with "/gun/phiSmearing", this command corresponds to the previous
"/generator/randomDirections" if "/gun/directionSmearingMode" is set to
"uniform".
/gun/phiStep

Sets a step by which the azimuthal angle of the gun will be changed after
each shot. The parameters are an optional scalar (default 0) with an
optional unit (default deg). This functionality is new.

/gun/phiSmearing

Sets an uncertainty (see "/gun/directionSmearingMode") by which the
azimuthal angle of the gun will be smeared in each shot. The parameters
are an optional scalar (default 0) with an optional unit (default deg).
Together with "/gun/thetaSmearing", this command corresponds to the
previous "/generator/randomDirections" if "/gun/directionSmearingMode" is
set to "uniform".

/gun/momentum

Sets the momentum of the particle gun, thus overwriting the kinetic
energy set by "/gun/energy". The parameters are a scalar (initial value
100.106 GeV) with an optional unit (default GeV). Together with
"/gun/momentumSmearing", this command corresponds to the previous
"/generator/gaussgun/momentum". Please note that this value will
implicitly change when you select a different particle type with
"/gun/particle": Whereas the kinetic energy is a basic property of the
Geant 4 particle gun, the momentum is only a derived property which is
calculated from mass and kinetic energy, so it will change when the mass
changes.

/gun/momentumStep

Sets a step by which the momentum of the particle gun will be changed
after each shot. The parameters are an optional scalar (default 0) with
an optional unit (default GeV). This functionality is new. Please note
that the momentum will get stuck if it reaches the boundary 0 GeV.


/gun/momentumSmearing

Sets an uncertainty (i. e. gaussian sigma) by which the momentum of the
particle gun will be smeared in each shot. The parameters are an optional
scalar (default 0) with an optional unit (default GeV). Together with
"/gun/momentum", this command corresponds to the previous
"/generator/gaussgun/momentum".

/gun/directionSmearingMode

Selects the random distribution which is used for the angular
uncertainties given by "/gun/thetaSmearing" and "/gun/phiSmearing". The
parameter is a string (candidates "gaussian" and "uniform", initial value
"gaussian"). A value of "gaussian" indicates that the angular
uncertainties are treated as gaussian sigmas, a value of "uniform"
indicates that the angular uncertainties are treated as half widths of a
uniform distribution. This functionality has been introduced for
compatibility with the previous "/generator/randomDirections".


/gun/info

Prints the particle type (including mass), nominal kinetic energy
(including momentum), nominal position, and nominal direction (including
theta and phi components) of the particle gun which will be used for the
next shot. Steps and uncertainties are not displayed. This command has no
parameters. It has been introduced to avoid confusion between
"/gun/energy" and "/gun/momentum".

The "step" and "smearing" commands are cumulative and permanent - their
effects add up and remain valid until the values are re-set. As opposed to
the previous implementation, none of the above commands actually fires the
gun - shots are now always fired by "/run/beamOn".

There have been suggestions to extend the existing single-particle gun in a
way that it can shoot two or even multiple particles with different
properties in a single event. However, for the sake of simplicity, these
ideas have been rejected for the time being. At some time in the future,
Mokka might include the "General Particle Source" which has much more
features than the standard Geant 4 particle gun.


VII. Interface for Guinea Pig Files

Mokka can now read files containing electron-positron pairs created by Guinea
Pig. These files must have names with the suffix ".pairs" (remember that a
symbolic link will do the job in case you're unable or unwilling to rename
your actual files) and can be accessed with the command
"/generator/generator".

Events are generated with the command "/run/beamOn". In the current
implementation, each event contains one single electron or positron because
one single bunch crossing can easily consist of more than 100,000 pairs.
Mokka will be aborted if you try to read past the end of the file, so you
should use a tool like "wc -l" to find out how many single particles (one per
line) are contained in your file.


Guinea Pig uses its own output format for the file "pairs.dat" which contains
the electrons and positrons created by the scattering of beamstrahlung in one
bunch crossing. Each line represents one particle and contains seven values:
the energy (in GeV, positive for electrons and negative for positrons), the
three components of the velocity (in units of the speed of light), and the
three components of the vertex position (in nanometres).


VIII. Restructured Plugin Directory

The contents of the directory "Mokka/source/Plugin" have been split up into
two subdirectories: One contains the "PluginManager" and the "Plugin" base
class, the other one contains all files for the "Checkplots" example plugin.
You may copy the whole directory "Mokka/source/Plugin/Checkplots" and use it
as a template for your own plugins. Make sure to include your plugins in the
top-level makefile "source/GNUmakefile" and in the main makefile
"source/Kernel/GNUmakefile" (just like it's done with the "Checkplots"
example) so that they get compiled and linked into the Mokka executable.


IX. New Hooks for Plugins

Up to now, plugins had the problem that it was not easy to control their
functionality with the help of steering parameters
("/Mokka/init/userInit..."): Plugins are realised as global static objects
(defined by the "INITPLUGIN(plugin, name)" preprocessor macro) and their
constructors - which usually perform the initialisation tasks - are called at
a very early stage of program initialisation. In particular, the steering
file has not yet been parsed for user parameters and UserInit therefore
cannot tell you any values. This problem could be worked around, but not very
elegantly.

For this reason, two hooks "void Plugin::Init(void)" and "void
Plugin::Exit(void)" have been added to the Plugin base class and also to the
PluginManager. These methods are called from main() immediately before the
user interface session is constructed and immediately after the session ends,
respectively. This way you can be sure that all managers are properly
initialised by the time the "Init()" method of your plugin is invoked. You
also know that all managers are still intact when the "Exit()" of your plugin
gets called. A further advantage is that "Init()" and "Exit()" will not be
called for inactive plugins, so your plugin won't do unnecessary work when
it's not activated via "/Mokka/init/registerPlugin" (constructors and
destructors will _always_ be called when your compiled plugin is linked into
the Mokka executable).

You can shift all your initialisation tasks from the constructor to the
"Init()" method and all clean-up tasks from the destructor to "Exit()".
However, you still have to provide a suitable constructor so that your plugin
can be registered with the PluginManager. This constructor doesn't have to
contain any actual statements, but it _must_ call the constructor of the base
class - otherwise your plugin won't be compiled:

MyPlugin::MyPlugin(const std::string &name): Plugin(name) {}


The internal management of the plugins has also been improved: The
PluginManager now checks whether all plugins have unique names and it will
print a warning message when you try to activate a plugin (via
"/Mokka/init/registerPlugin") which does not exist. Furthermore, the
performance of invoking the several hooks (which might have a significant
impact for the stepping and tracking actions) has been increased.


X. Modified Definition of the Material "beam"

The definition of the material "beam" has been modified. This material is
used to model the vacuum inside the beam pipe. Before, "beam" consisted of
air at a low density (1.0E-5 g/cm^3) and pressure (0.02 bar), but these
values were still too high and the material composition was not very
realistic either.


The estimated vacuum in the beam delivery system is described in a TESLA Note
(TESLA 2001-14) [5]. The main ingredients of the residual gas are CO/N2 (at a
pressure of 1.0E-8 mbar) and hydrogen (pressure approximately 5 times higher,
but not as relevant due to its small atomic number). The new "beam" material
definition uses 0.5E-8 mbar of CO, 0.5E-8 mbar of N2 (the actual ratio of
these two components is unknown), and 5.25E-8 mbar of H2, giving a total
pressure of 6.25E-11 bar and a density of approximately 1.7E-14 g/cm^3 at STP
temperature (0 deg C). The usage of such small values is made possible by the
recent removal of field width limits in the Mokka database.

Following Mokka's strict policy of backward compatibility, the modified
material definition has been put into a new MySQL database named
"materials01" which will be used by the CGAGeometryManager from now on.


XI. Revision of the Makefiles

The makefiles which belong to the Mokka source code have been revised and
partially shortened. Changes include:


* The variables "G4LIB" and "G4LIBDIR" are not set anymore because they can
be managed internally by the Geant 4 makefiles. As a result, your
"G4WORKDIR" doesn't get cluttered up by all kinds of directories anymore
- all dependencies, object files and object libraries are now put in
subdirectories of "$(G4WORKDIR)/tmp/$(G4SYSTEM)". The Mokka executable is
put in "$(G4WORKDIR)/bin/$(G4SYSTEM)", as before.

* The preprocessor flag "NDEBUG" (which you had to define if you did _not_
want debugging information, i. e. in the standard case) has been replaced
by "MOKKA_DEBUG", which you now have to define if you want additional
debugging information. The common makefile
"source/Kernel/GNUmakefile.common" looks for an environment variable of
the same name and sets the flag accordingly. The renaming also resolves
an overlap with low-level header files in which the same flag is used
(e. g. "assert.h"). In the same course, some assertions were replaced by
calls to "Control::Abort".

* The preprocessor flag "G4R4" is gone (both in the makefiles and in the
source code). It has become obsolete because there are other pieces of
code which need more recent versions of Geant 4 than just 4.0 and these
are not marked in any way. As always, you should use the latest release
of the software, which is Geant 4.7.1.patch01 as of November 2005.

* The support for a custom MYSQL_PATH has been moved to the common makefile
"source/Kernel/GNUmakefile.common". It is now handled in a similar way as
LCIO.

* The common makefile now contains only preprocessor flags which are
appended to the variable "CPPFLAGS". All library inclusions have been
moved to the main makefile "source/Kernel/GNUmakefile" and are appended
to the variable "EXTRALIBS" before "$(G4INSTALL)/config/binmake.gmk" is
read.


* The main makefile "source/Kernel/GNUmakefile" has been significantly
shortened: Many libraries could be left out because they are passed on to
the linker automatically by the Geant 4 makefiles. The options for the
different physics lists are now set by "$(foreach ...)" constructs. The
check for "G4LIB_BUILD_SHARED" has been removed because it is not needed
anymore. Multi-line statements (connected by backslashes) have been
transformed to multiple statements because it was difficult to comment
out one of the lines.

* The include preprocessor flags have been shortened to contain only those
paths which are actually needed for each module. The flags
"-I../../LHEP/include" and "-I../../Packaging/include" have been removed
completely because these modules have ceased to exist as a part of Mokka
- they are now provided by the Geant 4 framework.

* The file "$(G4INSTALL)/config/architecture.gmk" is not included
explicitly anymore because this is already done by
"$(G4INSTALL)/config/binmake.gmk".

* The variable "install" is not set anymore.


If you are not a developer, none of the above issues (except maybe the first)
should matter for you - simply type "make" and go to get some coffee.


XII. A Comment on Possible Linking Problems

If you are using granular Geant 4 libraries, you may want to note the
following: Each geometry driver and plugin is instantiated once as a global
static object by the preprocessor macros "INSTANTIATE" and "INITPLUGIN",
respectively, and then registers itself in a list of available code modules
which is kept by a manager. This technique has the advantage that it's
possible to add such modules without having to modify any part of the Mokka
kernel, but it also has the disadvantage of breaking the explicit chain of
dependencies between all the source files. The internal makefiles of Geant 4
rely on these dependencies and collect all libraries which are needed for the
process of linking the final Mokka executable (using the "liblist" tool). As
a result, Geant 4 does not know about the libraries which are _only_ referred
to by geometry drivers or plugins, so these libraries will have to be
included in the main makefile "Mokka/source/Kernel/GNUmakefile" by hand.


Currently this has to be done only for "libG4geomdivision" and
"libG4geomBoolean" because all other needed libraries are _also_ used by
pieces of code which are directly connected (via chains of "#include"
directives) to the top-level file "Mokka/source/Kernel/Mokka.cc". However,
this may change if future geometry drivers or plugins use other "exotic"
classes, and it will also change when you try to compile with special
settings such as the "G4VIS_NONE" flag, for example. (The kernel won't need
some graphics-related classes anymore, but the geometry drivers will still
refer to them.) To be able to link the Mokka executable in these cases,
you'll have to find out which classes cause the problem, which of the Geant 4
libraries contain them, and add these libraries to your main makefile by
hand. Keep in mind that their order matters to the linker because they may
again have depedencies among each other. In the example of "G4VIS_NONE",
appending "-lG4specsolids", "-lG4csg", and "-lG4graphics_reps" (in that
order) to the variable "EXTRALIBS" should currently be sufficient to build
Mokka successfully.

Please keep in mind that this is simply the price which has to be paid for
the flexible approach of geometry driver and plugin management.

XIII. Miscellaneous


* A problem with the geometry drivers "coil00" and "yoke00" has been fixed.
These drivers didn't close their database connections, i. e. they
didn't destroy the "Database" object which they created. This could
cause problems when many instances of Mokka were trying to access the
same database server because the number of MySQL connections is limited.
All driver developers should make sure that their own code doesn't
leave orphaned connections behind. See a related discussion [6] in the
Linear Collider Forum to find out more.

* A geometry overlap in the driver "tpc02" (constructing the subdetector
"tpc04") has been fixed: The overall mother volume of the TPC is now
large enough for the TPC endplates to fit inside. (Please note that this
fix might in principle affect backward compatibility.) Besides, the name
of the corresponding logical volume has been changed from
"TPCInnerShield" (obviously a typo) to "TPCMotherLog" and the copy number
of the second endplate (at z < 0) has been changed from 0 (already in
use) to 1.

* The file access permissions in the Mokka CVS repository have been changed
so that the files are not marked as "executable" anymore - as a
consequence, they won't show up in green in your favourite shell
when you unpack the Mokka tarball or checkout the sources via CVS.

* The width specifications for all fields of type "FLOAT" and "DOUBLE" have
been removed from the central MySQL geometry database. This solves a
problem with MySQL 4.1 which caused numerical values to be truncated when
they exceeded the maximum field width. See a related discussion [7] in
the Linear Collider Forum to find out more.

* The class "DchTbVisManager" and the method "DchTbHit::DrawWithVisM" have
been removed. They were not called from anywhere, but they caused trouble
when trying to compile with the preprocessor flag "G4VIS_NONE".

* A tiny bug in "CGAGeometryManager" has been fixed which caused a wrong
handling of LCIO versions x.0 and x.1 for x > 0.

* A new steering command "/Mokka/init/userInitBool" has been introduced to
define boolean variables cleanly. Possible values are "Y", "YES", "T",
"TRUE", or "1" on the one hand and "N", "NO", "F", "FALSE", or "0" on the
other hand, all case-insensitive.

* The existing commands "/Mokka/init/userInitDouble" and
"/Mokka/init/userInitInt" now do type-checking and will give you a
warning message at startup if they encounter invalid parameters.

* "UserInit" will now give you a warning when you try to define a user
variable twice - the second assignment will be ignored. "UserInit"
also checks whether a user variable has actually been defined when some
piece of code tries to get its value - if not, you'll get a default
return value (the empty string, zero, or "false") as before, but you'll
also get a warning message.

* The command "/generator/generator" will not abort Mokka anymore if a file
with the given name does not exist or cannot be opened.

* The "ControlMessenger" now makes use of the "G4Tokenizer" and the
conversion methods of "G4UImessenger" instead of handling string streams
by itself.


* You'll now get a warning message if "/Mokka/init/lcioWriteMode" has a
parameter value other than "WRITE_APPEND" or "WRITE_NEW".

* The "MySQLWrapper" now gets compiled without a warning message because it
uses standard functions from "stdlib.h" instead of the deprecated
"strstream" header.

* As you may already have noticed, all the release notes are now collected
in a subdirectory "Mokka/ReleaseNotes".


XIV. References

[1] http://tesla.desy.de/new_pages/TDR_CD/
[2] http://www-flc.desy.de/lcnotes/
[3] http://www-project.slac.stanford.edu/lc/bdir/Meetings/beamde livery/
2005-07-26/index.htm
[4] http://cmsdoc.cern.ch/~hpw/GHAD/HomePage/
[5] http://tesla.desy.de/new_pages/TESLA_Reports/2001/pdf_files/
tesla2001-14.pdf
[6] http://forum.linearcollider.org/index.php?t=tree&goto=33 7
[7] http://forum.linearcollider.org/index.php?t=tree&goto=34 2


XV. New Geometry Models "D14" and "D14_CMOSVTX"

Detector model D14 is same as D12 but contains new sub-detector VXD01 and
new beampipe TUBE02. VXD01 is the realistic geometry of the TESLA TDR vertex
detector. The 5 layers of the vertex detector are composed of ladders instead
simple cylinders used in previous version VXD00. The ladders are attached on
the beryllium support shell by beryllium annulus block. The first layer is
supported by beryllium disk placed directly on the beampipe. The description
of the beampipe TUBE02 is the same as TUBE01 but the radius of the beampipe
central part is 14 mm instead 10 mm to be consistent with the TESLA TDR.

The detector model D14_CMOSVTX is same as D12 but contains the new
subdetectors VXD02 and TUBE02. VXD02 is the realistic geometry of the CMOS
vertex detector concept.(see SNOWMASS 2005 presentations). The mecanical
support is the same as the VXD01 sub-detector.


For both new sub-detectors VXD01 and VXD02, the kapton strip line are still
modelled by cones as in the VXD00 sub-detector. This will be updated in the
next version.

These two new sub-detectors and the new beampipe are build with super
drivers: SVxd01 for the 2 vertex detector geometries and STube01 for the
beampipe. The 2 new super drivers have the following default values as
parameters:

1) SVxd01 - The user can change on fly few parameters of the VXD:
- The radius of the first layer and/or the fifth layer.
(the radius of the other layers are scaled and
the optimal number of ladders per layer is recalculated.)
- The thickess of the ladder support, the silicon active part and
the very front end electronics.
- The kind of material used for the ladder support
- The VXD is surounded by a cryostat or not.

+-------------------------------------+---------------+
| parameter | default_value |
+-------------------------------------+---------------+
| VXD_inner_radius | 15 |
| VXD_outer_radius | 60. |
| VXD_support_ladder_thickness | 0.28224 |
| VXD_active_silicon_thickness | 0.03744 |
| VXD_end_electronics_thickness | 0.19656 |
| VXD_cryostat_option | 1 |
| VXD_support_ladder_material | "beryllium" |
+-------------------------------------+---------------+

2) STube01 - The user can change the thickness of the central part of the
beampipe. The radius of the central part of the beampipe depends on the
radius of the first layer of the VXD. The beampipe will be placed always
at 0.5 mm of the first layer.

+-------------------------------------+---------------+
| parameter | default_value |
+-------------------------------------+---------------+
| TUBE_central_thickness | 0.5 |
+-------------------------------------+---------------+

exemple of steering commands :


/Mokka/init/globalModelParameter TUBE_central_thickness 0.2
/Mokka/init/globalModelParameter VXD_inner_radius 12
/Mokka/init/globalModelParameter VXD_outer_radius 80
/Mokka/init/globalModelParameter VXD_support_ladder_material "graphite"
/Mokka/init/globalModelParameter VXD_support_ladder_thickness 0.05
/Mokka/init/globalModelParameter VXD_active_silicon_thickness 0.05
/Mokka/init/globalModelParameter VXD_end_electronics_thickness 0.05
/Mokka/init/globalModelParameter VXD_cryostat_option 0
 
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