A newly upgraded version of the BCVEGPY, a generator for hadronic production of the meson $B_c$ and its excited states, is available. In comparison with the previous one [C.H. Chang, J.X. Wang and X.G. Wu, Comput. Phys. Commun. {bf 175}, 624 (2006)],
the new version is to apply an improved hit-and-miss technology to generating the un-weighted events much more efficiently under various simulation environments. The codes for production of $2S$-wave $B_c$ states are also given here.
The $B_c$ meson is a doubly heavy quark-antiquark bound state and carries flavors explicitly, which provides a fruitful laboratory for testing potential models and understanding the weak decay mechanisms for heavy flavors. In view of the prospects in
$B_c$ physics at the hadronic colliders as Tevatron and LHC, $B_c$ physics is attracting more and more attention. It has been shown that a high luminosity $e^+e^-$ collider running around the $Z^0$-peak is also helpful for studying the properties of $B_c$ meson and has its own advantages. For the purpose, we write down an event generator for simulating $B_c$ meson production through $e^+e^-$ annihilation according to relevant publications. We name it as BEEC, in which the color-singlet $S$-wave and $P$-wave $(cbar{b})$-quarkonium states together with the color-octet $S$-wave $(cbar{b})$-quarkonium states can be generated. BEEC can also be adopted to generate the similar charmonium and bottomnium states via the semi-exclusive channels $e^{+}+e^{-}rightarrow |(Qbar{Q})[n]rangle +Q +bar{Q}$ with $Q=b$ and $c$ respectively. To increase the simulation efficiency, we simplify the amplitude as compact as possible by using the improved trace technology. BEEC is a Fortran programme written in a PYTHIA-compatible format and is written in a modularization structure, one may apply it to various situations or experimental environments conveniently by using the GNU C compiler {bf make}. A method to improve the efficiency of generating unweighted events within PYTHIA environment has been suggested. Moreover, BEEC will generate a standard Les Houches Event data file that contains useful information of the meson and its accompanying partons, which can be conveniently imported into PYTHIA to do further hadronization and decay simulation.
We present an improved version of GENXICC, which is a generator for hadronic production of the doubly heavy baryons $Xi_{cc}$, $Xi_{bc}$ and $Xi_{bb}$ and has been raised by C.H. Chang, J.X. Wang and X.G. Wu [Comput. Phys. Commun. 177 (2007) 467; Com
put. Phys. Commun. 181 (2010) 1144]. In comparison with the previous GENXI
Neutron penumbral imaging technique has been successfully used as the diagnosis method in Inertial Confined Fusion. To help the design of the imaging systems in the future in CHINA. We construct the Monte carlo imaging system by Geant4. Use the point
spread function from the simulation and decode algorithm (Lucy-Rechardson algorithm) we got the recovery image.
In the present paper, we provide an addendum to improve the efficiency of generating unweighted events within PYTHIA environment for the generator BCVEGPY2.1 [C.H. Chang, J.X. Wang and X.G. Wu, Comput.Phys.Commun.{bf 174}, 241(2006)]. This trick is h
elpful for experimental simulation. Moreover, the BCVEGPY output has also been improved, i.e. one Les Houches Event common block has been added so as to generate a standard Les Houches Event file that contains the information of the generated $B_c$ meson and the accompanying partons, which can be more conveniently used for further simulation.
