The Virtual Monte Carlo

The concept of Virtual Monte Carlo (VMC) has been developed by the ALICE Software Project to allow different Monte Carlo simulation programs to run without changing the user code, such as the geometry definition, the detector response simulation or input and output formats. Recently, the VMC classes have been integrated into the ROOT framework, and the other relevant packages have been separated from the AliRoot framework and can be used individually by any other HEP project. The general concept of the VMC and its set of base classes provided in ROOT will be presented. Existing implementations for Geant3, Geant4 and FLUKA and simple examples of usage will be described.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 8 pages, LaTeX, 6 eps figures. PSN THJT006. See http://root.cern.ch/root/vmc/VirtualMC.htm

Measures of a sustainable commute as a predictor of happiness

The ways in which we travel—by what mode, for how long, and for what purpose—can affect our sense of happiness and well-being. This paper assesses the relationships between measures of the sustainability of transportation systems in U.S. metropolitan areas and subjective well-being. Associations between self-reported happiness levels from the Gallup Healthways Well-being Index and commute data were examined for 187 core-based statistical areas (CBSA). Wealsosupplementthisquantitativeanalysisthroughbriefcasestudiesofhigh-andlow-performing happiness cities. Our quantitative results indicate that regions with higher commute mode shares by non-automobile modes generally had higher well-being scores, even when controlling for important economic predictors of happiness. We also find that pro-sustainable transportation policies can have implications for population-wide happiness and well-being. Our case studies indicate that both high and low scoring happiness cities demonstrate a dedicated commitment to improving sustainable transportation infrastructure. Our study suggests that cities that provide incentives for residents to use more sustainable commute modes may offer greater opportunity for happiness than those that do not

Mutual positions of the Galilean satellites of Jupiter from photometric observations during their mutual occultations and eclipses in 1997


We report the final results of the 1997 campaign of
photometric observations of the mutual phenomena of the Galilean
satellites carried out at observatories in Kazakhstan, Russia, and
Ukraine. Our results contribute substantially to the
world data bank of such observations
and will allow the model of the motion of Galilean 
satellites to be further refined. To facilitate the use of
photometric data, we reduced them by computing the planetocentric
rectangular
coordinate differences of satellite pairs for a number of instants
of time so we deduce the differences for one instant from one
observed light curve.
It is these reduced data that constitute the principal result of this work. We based our data reduction on the method which we developed in
earlier papers (Emel'yanov 1999; Emel'yanov 2000). The accuracy of observations was estimated in the process of reduction. The paper also describes the equipment used.

The Virtual Monte Carlo

Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 8 pages, LaTeX, 6 eps figures. PSN THJT006. See http://root.cern.ch/root/vmc/VirtualMC.html - Available at http://www.slac.stanford.edu/econf/C0303241/proc/papers/THJT006.PDFInternational audienceThe concept of Virtual Monte Carlo (VMC) has been developed by the ALICE Software Project to allow different Monte Carlo simulation programs to run without changing the user code, such as the geometry definition, the detector response simulation or input and output formats. Recently, the VMC classes have been integrated into the ROOT framework, and the other relevant packages have been separated from the AliRoot framework and can be used individually by any other HEP project. The general concept of the VMC and its set of base classes provided in ROOT will be presented. Existing implementations for Geant3, Geant4 and FLUKA and simple examples of usage will be described

Generation of nonlinear electric field bursts in the outer radiation belt through the parametric decay of whistler waves

International audienceHuge numbers of different nonlinear structures (double layers, electron holes, nonlinear whistlers, etc., referred to as Time Domain Structures, TDS) have been observed by the electric field experiment on the Van Allen Probes. Some of them are associated with whistler waves. Such TDS often emerge on the forward edges of the whistler wave packets and form chains. The parametric decay of a whistler wave into a whistler wave propagating in the opposite direction and an electron acoustic wave is studied experimentally as well as analytically, using Van Allen Probes data. The resulting electron acoustic wave is considered to be the source of electron scale TDS. The measured parameters of the three waves (two whistlers and the electron acoustic wave) are in good agreement with an assumption of their parametric interaction: í µí¼ 0 = í µí¼ 1 + í µí¼ 2 and ⃗ k 0 = ⃗ k 1 + ⃗ k 2. The bicoherence analysis shows the nonlinear nature of the observed electron-acoustic waves as well as the whistler wave and electron acoustic wave phase relation. The estimated decay instability growth rate shows that the process of three-wave interaction can develop in a characteristic time smaller than 1 s, thus, the process is rapid enough to explain the observations. This induced parametric interaction can be one of the mechanisms for quasiperiodic TDS generation in the outer Van Allen radiation belt

Mutual positions of the Galilean satellites of Jupiter from photometric observations during their mutual occultations and eclipses in 1997


We report the final results of the 1997 campaign of
photometric observations of the mutual phenomena of the Galilean
satellites carried out at observatories in Kazakhstan, Russia, and
Ukraine. Our results contribute substantially to the
world data bank of such observations
and will allow the model of the motion of Galilean 
satellites to be further refined. To facilitate the use of
photometric data, we reduced them by computing the planetocentric
rectangular
coordinate differences of satellite pairs for a number of instants
of time so we deduce the differences for one instant from one
observed light curve.
It is these reduced data that constitute the principal result of this work. We based our data reduction on the method which we developed in
earlier papers (Emel'yanov 1999; Emel'yanov 2000). The accuracy of observations was estimated in the process of reduction. The paper also describes the equipment used.