Second Semester Homework

Home Work 1 (2/11/16)      

Ok, after looking at Tal’s code and Jacobs logbook, I became aware of several mistakes that were hindering my progress greatly

·       Firstly, my mass was not an array, it was just an integer, hence why I was only getting one number.

·       I was correct in figuring out how to isolate the electrons using a temporary variable and their PPID

·       I also did not know that when doing the DY, you were supposed to keep the regular Z Boson cards in place, I kept commenting them out which was probably an issue as well

·       Here is an explanation of what the new added Z Boson lines do

  pythia.readString("NewGaugeBoson:ffbar2gmZZprime = on");

                  Sets the scattering to be a fermion and an anti fermion to a Z prime boson

  pythia.readString("32:m0 = 150.");

Sets the nominal mass to 150

  pythia.readString("32:mMin = 90.");

Restricts the invariant mass to be above 90

  pythia.readString("32:mMax = 300.");

Restricts the invariant mass to be below 300

pythia.readString("PhaseSpace:mHatMin = 20. ");

Sets the minimum invariant mass to 20

  pythia.readString("Zprime:gmZmode = 3");

You choose the contributions such as gamma^*, Z^0, or Z^’0. Option 3 means only Z^’0 contributions.

  pythia.readString("Beams:eCM = 14000.");

Sets the collision center of mass energy to 14 TeV

  pythia.readString("32:onMode = off");

  pythia.readString("32:onIfAny = 11");

·       Here is the proper Invariant Mass Histogram with the spike at 1500 GeV

I borrowed some of Tal’s aesthetic tricks to make the graphs look really nice so here is the comparison of DY with regular Z for 1000 events

·       This next part dealing with the background was very confusing and I am very glad that Tal, Jacob, and Avi were able to figure it out. I thought that the sigma was the sigmaInteraction that was mentioned but I guess it’s some other number, I’m not sure how those guys knew that.

·       Anyways, the number we are actually looking for is the sigma number on the right hand side, 7.330 E-11 mb. This is for the DY events

·       To calculate the number of events produced, use the formula

·       So for the Regular Z Boson, the equation is (Don’t forget to convert!)

·       For some reason, I can’t get the sigma from the DY events to show up L

·       I don’t know exactly what the ratio is but there is a lot more background than signal

·       In order to increase the ratio, a cut should be made around 200 GeV in order to eliminate the background

Finally, the mass with a cut at 200 GeV

Homework 2 (2/14/16)

·      Running the initial set up commands went well. Checked back with HW1 just to double check how to git clone. After the ./example run an image popped up as well as a lot of information. I will attempt to interpret what it is saying

·      It appears to have done an analysis of 3 different materials: lead, liquid Argon, and something called Galactic.

·      It has data for each element

o   Z = # of protons

o   N = Mass #

o   A = mass

·      It also has data on density, RadL, Nucl.Int.Length, and Imean

·      There is also data on the makeup of the calorimeter

·      It did this later, which I am pasting here because I think it will be important to know what type of variable each of these methods takes

Attributes available for modeling and filtering with

  "/vis/modeling/trajectories/create/drawByAttribute" and

  "/vis/filtering/trajectories/create/attributeFilter" commands:

G4TrajectoriesModel:

  Event ID (EventID): G4int

  Run ID (RunID): G4int

G4SmoothTrajectory:

  Charge (Ch): unit: e+ (G4double)

  Track ID (ID): G4int

  Initial kinetic energy (IKE): G4BestUnit (G4double)

  Initial momentum magnitude (IMag): G4BestUnit (G4double)

  Initial momentum (IMom): G4BestUnit (G4ThreeVector)

  No. of points (NTP): G4int

  PDG Encoding (PDG): G4int

  Parent ID (PID): G4int

  Particle Name (PN): G4String

G4SmoothTrajectoryPoint:

  Auxiliary Point Position (Aux): G4BestUnit (G4ThreeVector)

  Step Position (Pos): G4BestUnit (G4ThreeVector)

·       It provides a lot of options later such as

Draw hits at end of event:

#/vis/scene/add/hits

#

# To draw only gammas:

#/vis/filtering/trajectories/create/particleFilter

#/vis/filtering/trajectories/particleFilter-0/add gamma

#

# To invert the above, drawing all particles except gammas,

# keep the above two lines but also add:

#/vis/filtering/trajectories/particleFilter-0/invert true

#

# Many other options are available with /vis/modeling and /vis/filtering.

# For example, to select colour by particle ID:

#/vis/modeling/trajectories/create/drawByParticleID

#/vis/modeling/trajectories/drawByParticleID-0/default/setDrawStepPts true

# To select or override default colours (note: e+ is blue by default):

#/vis/modeling/trajectories/list

#/vis/modeling/trajectories/drawByParticleID-0/set e+ yellow

#

# To superimpose all of the events from a given run:

/vis/scene/endOfEventAction accumulate

·  It appears that /vis/modeing and /vis/filtering will be very usefull

·  It is now displaying Idle> so I assume it is asking me for commands similar to the way we entered root and used commands in the root environment

·  The command /run/beamOn 1 gave me a lot of data, most notably it outlined all of the Hadronic processes for all sorts of particles from neutrons to pion+ to positrons and muons

·  At the end of the data, this was outputted which seems like it might be an issue but I’m going to choose to ignore it until it actually messes something up

XIO:  fatal IO error 0 (Success) on X server "localhost:11.0"

      after 212 requests (211 known processed) with 20 events remaining.

WARNING - Attempt to delete the physical volume store while geometry closed !

WARNING - Attempt to delete the logical volume store while geometry closed !

WARNING - Attempt to delete the solid store while geometry closed !

WARNING - Attempt to delete the region store while geometry closed !

·   I did not initially get a pretty picture to pop up so I ran the example code again and this time I didn’t close the window that popped up but it was still a black canvas with white rectangles on it, nothing too fancy

·   In the second run, the fatal error did not occur and a ton more data was outputted it took forever to scroll through but I think the error might have occurred because I closed the window

·   I saw this at the very bottom of the run

WARNING: 1 event has been kept for refreshing and/or reviewing.

  "/vis/reviewKeptEvents" to review them.

·   So I typed /vis/reviewKeptEvents and it gave me a list of commands so on a hunch I used the command /vis/scene/add/trajectories and right away a lot of lines appeared on the canvas which is displayed below

·  As evident from the picture, it is mostly green so id have to look in the example code to see what track was set to the color green. Another notable thing about this picture is the red line going perfectly straight to the left

The histograms in the B4.root file were pretty uneventful, plotting things like Eabs, Egab, Labs, and Lgap

2/17/17

• I have now encountered some problems with GEANT

• I am getting the error "/home/eno/CMSSW_7_4_0: No such file or directory." when I try to run "source G4_Setup.sh"

• It worked the other day and it seems like other people are having the same problem so I'm going to wait until this weekend to work on it