Ejercicio 2

Con el ejercicio siguiente, puedes testear cuan bueno es tu dominio de identificación de sucesos. Hemos escogido, para ello, diez ejemplos. Están almacenados aquí en formato electrónico para que los bajes. En las Clases Magistrales Internacionales, están ya almacenados en el ordenador. Tienen que ser leidos con el programa MINERVA (con "leer sucesos localmente")



Tu tarea es didtinguir entre suceso de señal y ruido. Los sucesos de señal producen exactamente una partícula W. En ellos tienes que determinar, también, si la partícula W ha decaido en un electrón o positrón o en un muon o antimuon, y el (anti)neutrino asociado. Sucesos con jets, partículas Z y pares de quark top son sucesos de ruido



Puedes chequear tus resultados usando la tabla de abajo. Para cada suceso, escoge el proceso que crees que ha producido el suceso. Pulsando "Confirmar tarea" puedes ver el número de sucesos correctamente identificados. Pulsando "Respuestas correctas" puedes ver las respuestas correctas



¡Diviértete con el test!
 
Event
W+→e++νe
W-→e-+
ν
e
W+→μ++νμ
W-→μ-+
ν
μ
WW-→l-+
ν
l+l++νl
Background
01
02
03
04
05
06
07
08
09
10




  • 0 MINERVA can only display information on muons in cross-sectional view if the muon travels through the barrel region. In this example the muon leaves in forward direction and thus can only be identified with help of the side view. Tracking and calorimeter information is available in cross-sectional view though.
  • The red track cannot be identified as an electrically charged lepton, arisen from a different vertex (compared to the positron shown with orange track) and is thus not of interest.
  • Missing transverse energy is too little.
  • Missing transverse energy is too little. Electron candidate (orange track) is not well isolated from electrically charged particles around.
  • MET>25 GeV, there is exactly one electron (electric charge = -1) in the event, well isolated. It is not visible in cross-sectional view since it moves in forward direction but can be clearly identified in side view.
  • MET>25GeV, there is exactly one anti-muon (electric charge = 1) arising from the right vertex (see enlarged side view on bottom left), well isolated, with PT>20GeV.
  • MET > 25 GeV. Two hight-PT, isolated tracks arising from two vertices. Only the red track (PT > 20 GeV) can be combined with calorimeter clusters and thus identified as electron (electric charge = -1).
  • MET > 25 GeV, there are exactly two, oppositely electrically charged leptons in the event (a positron and a muon), both are well-isolated from Jets. The muon can only be identified in side view since it moves in forward direction. There is also another high-PT track in the event, which cannot be assigned to third electrically charged lepton.
  • Possible muon candidates are not isolated from Jets.
  • There are two orange tracks in the event. The one that can be combined with clusters in the calorimeter goes up in cross-sectional-view. It is overlaid by a purple track, whose accompanying particle was produced so close to our electron candidate, that we cannot really say it was isolated (look at the enlarged views).