Aranya Banerjee

I talked to Kaustubh Agashe today. He reviewed basic concepts that would relate to our research such as the Standard Model, subatomic particles, the four fundamental interactions, and Feynman diagrams. He then outlined the basic idea of the models that we would look to validate, which propose a warped, compact (finite) fifth dimension in addition to the four-dimensional space-time that we observe. The dimension must be finite rather than infinite as the other three spatial dimensions are because otherwise forces such as gravity and EM would have a falloff of 1/r^3 rather than 1/r^2.

Next Dr. Agashe outlined the results from this theory of a fifth spatial dimension that we could look to verify in our data analysis. Spatial momentum in the extra spatial dimension results in extra energy in the general equation for five-dimensional space-time, E^2 = |p|^2 + |p5|^2 + m^2c^4, where p is spatial momentum in third dimensional space and p5 is spatial momentum in the third dimension, and that extra energy appears in the general equation for four-dimensional space-time, E^2 = |p| ^ 2 + |p5|^2 + m^2*c^4, as additional mass. In this ways particles may have states of greater mass called Kaluza-Klein particles. The collection of the Standard Model (SM) particles and their corresponding Kaluza-Klein (KK) excitations is known as the Kaluza-Klein Tower. He explained that a collision between quarks and their respective anti-quarks can produce one excitation, which then decay into both the standard model particle that corresponds to the K excitation and a radion, the particle that describes the interaction with the fifth dimension, which subsequently decays into a pair of quarks independent of the original KK excitation. This process, where a product of decay was unstable and decayed itself, is an example of a cascade decay. In order to identify when the final state of this signal is the result of a KK excitation and not background noise in the SM model, we will have to suppress background noise by examining the frequency of the aforementioned state with relation to the invariant fixed mass of the radion and the invariant mass of the KK excitation. Bumps in the data at these values will indicate the signal that we are looking for.

01/30/18

Today I continued to learn the theory of the model that I would be studying. Mr. Du told us that we are studying phenomenology. Phenomenology is the bridge between theory and experiment in that we build models that we know can be tested. He also introduced the Hierarchy Problem. The Hierarchy Problem asks why gravity is so weak next to the weak nuclear force. This is answered in the theory of the Extended Randall-Sundrum Model, which proposes UV brane, a Higgs brane, and an IR brane. A brane, short for membrane, is something I don't understand. The profile of the gravitron (the force carrier for gravity) with respect to the fifth dimension, which is the gravitron's interaction along the fifth dimension from one brane to another, decays exponentially from the UV brane to the Higgs brane, and the profile of the Higgs Boson does vice versa. This decay is due to the fifth dimension being a highly warped space-time, called an anti-de Sitter space.

In our research we will look at two specific signed channels, the Wγγ Channel and the Tri-Photon Channel.

We are changing our meeting times from 11am-12pm on Tuesdays to 3:30pm-4:30pm on Thursdays.

02/09/18

Mr. Du gave us an overview of the theory in collider physics. To make up for limited time to meet, he emailed us a paper to read over the week to get some grasp on partons and parton distributions. I have not understood most of it.

02/15/18

This week was exciting. I had already installed MadGraph the previous semester, so Mr. Du walked us through performing simulations of events on the cluster. I learned about generating processes, understanding the parameter and run cards, accessing the output, couplings, kinematic cuts, and the upper limits to what I can simulate until I learn to use Condor. Over this week I will learn more about the kinematic cuts and practice simulating events on my own.

02/22/18

We went over simulations in MadGraph that we had done for practice over the past week. We installed Delphes spent time trying to install the newest version of pythia on the cluster and failing. After the meeting, we found that "install pythia-pgs" installs Pythia6 fine. Over this week I will continue to generate events and look more closely at the lhe and lhco files. I will also have Mathematica installed for the next meeting so that we can start doing analysis of results.

download/install mathematica

delta R is sqrt (delta(eta)^2 + delta(phi)^2) meaning angle between particles in their collission

pt is transverse momentum meaning momentum perpendicular to direction of beam because thats what gets measured, the 1

eta is angle

more eta means more momentum along z direction, which is beam direction

.lhe: each event has 4-momentum

Today:

Madgraph parton level events: hadronization/shower of quarks and gluons: we will never see quarks and gluons because QCD(Quantum ChromoDynaics) is strong force between quarks to put them together into color neutrual mesons

pythia will simulate the hadronizations/showers

jet is a bounty of particles produced from

quark jetes come from quarks

gluon jets come from gluons

in collider we cant distinguish between the two above

Delhes does detector simulation

It gives us the 4 momenutm of jets (the average of its particles), photons, leptons, missing energy: MET (neutrinos)

we assume momentum conservation along the transverse plane, then we can calculate to have

MET = -sigmaPt(visible)

to get Pythia

install pythia8

install Delphes

for install pythia8, was told to install [lhapdf6?], saw that

scp [localfile] hon17_banerjee@hepcms.umd.edu:~

03/01/18

I simulated 10000 events of the process p p > bkk > a r , r > a a, which is the collision of quarks to produce a kk fermion that decays into a photon and

type 6 is the missing energy

some have 1,2,3 jets, which are type 4

all have missing energy

this may be due to energy of some mesons having very small energy that does not pass detecteor threshold and od not get detected

pta momen for photon

ptl p for lepton

drjj delta for 2 jets, their angular diff must be more than .4

03/08/18

today we learn to remove background from signal

notebook has feynman diagram, so does index.tml for simualted

1. pp > aaa

2. pp > jaa(a jet fake a photon) meaning to detector it looks like photon

Physical process; pions (pi superscript 0) inside jet can decay to 2 photons, which merge togeter to be detected as one photon

this is background because it results in same final state as signal resulting from different process

cross section (denoted by sigma)

cross section (pp>jaa) >> cross section (pp>aaa)

If we consider jet faking photon rate (demoteed eta), eta << 1, sigma(pp>jaa)*eta ?>= sigma(pp > aaa)

so more background eevents are

3. pp > jja

4. pp > jjj

How many signal and background events do we need to simulate?

cross sections:

sg:sigma(sg)

bg:

sigmaL = num of real events

L is LHC luminosity

simulated events: real evetns after cuts >= sigma(1)

BGL After cuts, Nmg = num Madgraph events after cuts

1/sqrt(Nmg) is statistical fluctuation

ideally: statistical fluctutation <= .1

so we want Nmg >= 100

Weights for Madgraph events

W = sigmaL/(num simulated MD events) <= 1

^num simulated MG events is before kinematic cuts

Meaning

1 madgraph event corresponds to W real events

Having more madgrapg events for each real events is better because we can resolve distribtions

cross section of the events

smaaa: .1pb (picobar)

back2: 99pb

signal: .1fb (fentobar, one onethousand of pb)

SG: sigma(sg) = .11fb

L = 300 to 3000 /fb

real events: 33 to 330

in practice: we need 50k sg MG events

BG1: 1000 times larger

we need to cut out a 1000 bg events to see a signal

BG2: we need to cut out 1mill events

Not feasible to generate so many events to do this, not practical

Solution for getting bg closer to sg region:

Need to add kinematic cuts at MG simulation

graph of

hw: get distribution of kinematic cuts and see where on graph bg and sg cross for them, then put those numbers in run crd

then you get new cross sections for bg

Apply same cuts to both background and signal

Important note: there is cut-decay in run crd

its default is fale

we change it to true for every cut that we do

start by simulating 10k events

Next time we will learn to do 50k with condor

03/27/18

cut notes

sg/sqrt(sg+bg)

300/fb=luminosity

sg=cross*luminosity*cut efficiency=cutevents/totalevents)

bg=cross*luminosity*(ut efficiency=cutevents/totalevents)

03/29/18

weight for mg events:

w = real events / (#mg events simulated) < 1

BG1: pp>aaa

real events:

04/05/18

absolute path commands:

convert root file to lhco file/

command/

Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/Delphes/root2lhco Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/mar29condor_bkk_aaa/Events/run_01/tag_1_delphes_events.root Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/mar29condor_bkk_aaa/Events/run_01/tag_1_delphes_events.lhco

/end of command

1st part is executable, 2nd part is root, 3rd is new lhco file

Should see:

** Reading Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/mar29condor_sm_jaa/Events/run_01/tag_1_delphes_events.root

** Input file contains 50000 events

** [################################################################] (100.00%)

** Exiting...

/end of convert root file to lhco file

copying from cluster(remote) to machine(local)/

scp hon17_banerjee@hepcms:Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/mar29condor_bkk_aa

a/Events/run_01/tag_1_delphes_events.lhco /home/Aranya/../../mnt/c/Users/arany/Downloads/

/end of command

Should see:

The authenticity of host 'hepcms (128.8.216.193)' can't be established.

RSA key fingerprint is 82:b3:db:a7:4d:34:77:5a:50:49:38:56:4e:3b:8e:59.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'hepcms' (RSA) to the list of known hosts.

hon17_banerjee@hepcms's password:

tag_1_delphes_events.lhco 100% 21MB 1.9MB/s 00:11

/copying from cluster(remote) to machine(local)

submit condor job/

condor_submit condor_SG_jobs.jdl

/end of command

edit Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/command.cmd to edit condor job

/end of submit condor job

04/10/18

Cuts I used in apr10 file:

mmaa 500

mmjj 500

pta 50

ptj 50

04/11/18

for new models, put under models folder in madgraph and unzip

04/12/18

For wkk analysis, first run was in file

apr12wkklaa

generate p p > wkk+ > w+ r , r > a a , w+ > l+ vl

add process p p > wkk- > w- r , r > a a , w- > l- vl~

10000 events

cross section: 7.762e-05 ± 6.081e-08 (pb)

04/17/18

Wγγ channel has quark and antiquark collide to produce charged (+/-) KK w boson, which decays into w boson, which decays into lepton and leptonic neturino, and radion, which decays into two photons. Final state seen at detector is 2 photons, lepton, and missing transverse energy.

generating processes for the Wγγ channel:

Signal Process:

import model Radion_EW

/*unchanged code*/

generate p p > wkk+ > w+ r , r > a a , w+ > l+ vl

add process p p > wkk- > w- r , r > a a , w- > l- vl~

Background Process 1:

import model sm

/*unchanged code*/

generate p p > w+ a a, w+ > l+ vl

add process p p > w- a a, w- > l- vl~

Background Process 2:

import model sm

/*unchanged code*/

generate p p > w+ j a, w+ > l+ vl

add process p p > w- j a, w- > l- vl~

Tri-Photon Channel Processes:

Signal Process:

import model Radion_BKK

/*unchanged code*/

p p > bkk > a r , r > a a

Background Process 1:

import model sm

/*unchanged code*/

p p > a a a

Background Process 2:

import model sm

/*unchanged code*/

p p > j a a

Background Process 3:

import model sm

/*unchanged code*/

p p > j j a

04/18/18

generating 4 runs of 50000 events for each process

identical cuts for all of them for now (just seemed fine this way for now)

mmaa 500, pta 40, ptj 40 at generation level

may 18 bkk analysis

bkk

aaa

jaa

jja

may 18 ew analysis

laa

lja

may 18 faking analysis

sm aaa

sm jaa

sm jja

04/26/18

I learned (very late) that vector boson, gauge boson or spin 1 particle are the same thing.

I resolved problems with doing multiple runs in Condor. Delphes was not being turned on by the numerical commands that work on the first run. Instead, the command.cmd file must have detector=Delpes to generate root files for each run.

I am preparing to do a large scale analysis of both channels that I've looked at over this semester. I will be using cuts according the distributions and significance measures that I obtained in past analyses.

04/28/18

Analyzing the triphoton channel, w gamma gamma channel, and jet-faking-photon rate with 3 processes for each analysis:

triphoton

1. p p > bkk > a r , r > a a

2. p p > a a a

3. p p > j a a

w gamma gamma

1. p p > wkk+ > w+ r , r > a a , w+ > l+ vl with p p > wkk- > w- r , r > a a , w- > l- vl~

2. p p > w+ a a, w+ > l+ vl with p p > w- a a, w- > l- vl~

3. p p > w+ j a, w+ > l+ vl with p p > w- j a, w- > l- vl~

jet-faking-photon

1. p p > a a a

2. p p > j a a

3. p p > j j a

Cuts for each process:

triphoton

Generation level: invariant mass of photon pairs above 500

Analysis level: invariant mass of photon pairs between 900 and 1100 GeV, reconstructed mass above 2500 GeV

w gamma gamma

Generation level: invariant mass of photon pairs between 500 and 1500 GeV

Analysis level: invariant mass of photon pairs between 900 and 1100 GeV, invariant mass for all photons above 2800 GeV

Did 20 runs of 50000 events for each process in both channels, did 10 runs of 50000 events for each process in the jet-faking-photon analysis

Template condor file for 10 runs of 50000 events:

import model sm

# Define multiparticle labels

define p = g u c d s u~ c~ d~ s~

define j = g u c d s u~ c~ d~ s~

define l+ = e+ mu+

define l- = e- mu-

define vl = ve vm vt

define vl~ = ve~ vm~ vt~

# Specify process(es) to run

generate p p > j a a

output apr28jaa2

launch

# setting run card parameters

set nevents 50000

set ebeam1 7000

set ebeam2 7000

#remember cutdecays is true when cutting

set cut_decays True

set mmaa 500

# run02

launch apr28jaa2

detector=Delphes

# run03

launch apr28jaa2

detector=Delphes

# run04

launch apr28jaa2

detector=Delphes

# run05

launch apr28jaa2

detector=Delphes

# run06

launch apr28jaa2

detector=Delphes

# run07

launch apr28jaa2

detector=Delphes

# run08

launch apr28jaa2

detector=Delphes

# run09

launch apr28jaa2

detector=Delphes

# run10

launch apr28jaa2

detector=Delphes

04/29/18

Several parts of this process are very slow, so I have developed scripts to automate what took so much time right now that it was worth the investment: Scripts for converting root files to lhco files for all runs in a folder and for copying lhco files to local machine are at the bottom, adapted for my own settings. Mathematica needs to be rewritten. Mathematica is the bottleneck for my analysis, where I need to wait for long durations of time for analysis to complete. I also continued using the code I developed for calculation of weights, real events, cut efficiency, and significance.

MADGRAPH NOTES

GETTING TO MADGRAPH

cd __CMSSW object with madgraph in it

cd Phys268n/CMSSW_8_0_22/src

cmsenv

^ In above, runs the environment

cd MADGRAPH/MG5_aMC_v2_6_0

./bin/mg5_aMC

^In above, ./ runs the executable

RUNNIG MADGRAPH

Model

sm (standard model) is for backgrounds

in madgraph, we do >>import modell xx

^In above, xx is model name (like sm)

Radion_EW.. (our signal)

If you add a new model files, put it in Madgraph/models/

particle containt

Defined multiparticle p = g u c d s u~ c~ d~ s~

Defined multiparticle j = g u c d s u~ c~ d~ s~

Defined multiparticle l+ = e+ mu+

Defined multiparticle l- = e- mu-

^ In above, j is jet: collection of quarks (u,d,c,s,g), p is proton also with all quarks, l is lepton. ~ means antiparticle. The gluon is its own antiparticle. g u c d s u~ c~ d~ s~ are all partons. They are distributed according to different parton distribution functions.

generate process:

>generate p p > z > e+ e-

^ Above generates a process

output process:

>output [filename]

run the process

>> launch [filename]

several options such as

pythia:

delplex:

We type 0 and enter it

we then see 2 cards

1 to get to parameter card

parameter card has all properties of particles: mass, coupling. Block mass is mass of particle. MT is mass of top quark. ALl numbers are in GeV

Then shows 0 mass for up down charm all quarks. THey are 0 in here because they are relativelyalmost massless for higher energies

Blocksminputs are couplings

aewmi is electronmagneti coupling

fermi constant

strong coupling

Above values are inverses apparently? 1/ value

INFORMATION FOR DECAY

decay width is how fast particle will decay

WZ is Higgs

For new models if you want to test a new parameter soace and change mass decay width (we change nothing for sm)

To exit file from vi editor:

:q quits

:q! force quit if you changed something but does nt want to save it

:wq to write and quit

:i to insert mode

esc to leave insert mode

2 to get to run_card.dat

[num of simulated events] = nevents

cant run for 1m plus events becasuse file would exceed 1GB, so make multiple files instead

We would want to use 50,000 for reasonable signal analysis

1000 or some other smaller number is good for quick testing

Dont simulate more than 10,000 events at a time right now because we only have 1 or 2 nodes in cluster for use. We will learn to use Condor in the future which will allow more nodes and it will continue running even when we log off.

The 0 =n means no parton distribution function, meaning equal distribution of the different particles

1 beam is 6500 GeV.

The two beams together give the 1300 GeV we normally see in LHC. We can simulate higher energies

Kinematic cuts

under the title Parton level cuts definition

False = cut-decays

means no kinematic cuts applied

For our signal we will always do True = cut-decays

Under title Standard CUts

Then there are standard]pt2 is ttransvere momentum

WE use cuts to get rid of alot of background

It is called kinematic cut because we cut evnts based on kinematics

We will have stronger cuts then what are in place for the collider simulation.

Important question we will look at is how to make cuts

Homework is to look at following cuts below

min ptj pt1

max __ __

ej (energy)

rapidity

dr (delta r)

exit from madgraph after running simulatiion

firefox HTML

I will get webpage with info

Besides that, I can cd to Events

cd to run

gunzip unweighted events

I will get unweighted.

vi unweighted

scroll all the way down to unweighted

homework is to check physics=al meaning of each column in.lhe

first col is name of particles

sec

thir

first four large are four momentum

fifthh large is mass

Homework is to generate abother oricess with pp> e+e- (not specifying z in between, includes pp to photon) and then checking the Feynman diagrams

The Feynman diagrams are on theHTML webpage

Next time well be sent a madgraph file to work with

LHE AND LHCO INSTRCUTIONS

first go to

cd [eventoutputfilename]/Events/run_01/

to unzip MADGRAPH lhe file,

gunzip unweighted_events.lhe.gz

ro unzip pythia lhe file,

gunzip tag_1_pythia_events.lhe.gz

then

in the Delphes folder, execute

./root2lhco ../[processname]/Events/run_01/tag_1_delphes_events.root ../[processname]/Events/run_01/tag_1_delphes_events.lhco

PRINTING CONDOR RUNS

vi Phys268n/condor/MG5test_286304_0.stdout

where 286304_0 above should be replaced with run number

AUTOMATED SECURE COPY LHCO FROM REMOTE TO LOCAL

bash script starts/

rm -r /home/Aranya/../../mnt/c/Users/arany/OneDrive/College/umd/fresh/sem2/269/$1

mkdir /home/Aranya/../../mnt/c/Users/arany/OneDrive/College/umd/fresh/sem2/269/$1

for i in 0{1..9} {10..10} ; do

scp hon17_banerjee@hepcms:Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/$1/Events/run_$i/tag_1_delphes_events.lhco /home/Aranya/../../mnt/c/Users/arany/OneDriv\

e/College/umd/fresh/sem2/269/$1/$1_$i

done

/bash script ends

AUTOMATED ROOT TO LHCO CONVERSION

tcsh script begins/

#!/usr/bin/env tcsh

foreach run (*Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/$1/Events/run*)

echo $run

Phys268n/CMSSW_8_0_22/src/MADGRAPH/MG5_aMC_v2_6_0/Delphes/root2lhco $run/tag_1_delphes_events.root $run/tag_1_delphes_events.lhco

end

/tcsh script ends

CALCULATION OF SIGNIFICANCE

c file begins/

#include <stdio.h>

#include <math.h>

#define NUM_BG 2 /*num background events to calculate cut efficiency for*/

#define LUMINOSITY 300 /*in fb*/

#define MADGRAPH_EVENTS 50000 /*number of events simulated in madgraph*/

/*ORDER IN ARRAYS: sg,aaa,jaa*/

int main() {

short i = 0;

double significance,sg_and_bgs[NUM_BG+1],cut_efficiency[1+NUM_BG], num_real_events[1+NUM_BG];

double cross_section[1+NUM_BG] = {0.0001365,1.362*.00001,0.09078}; /*in pb from MADGRAPH, will convert to fb next*/

double cut_events[1+NUM_BG] = {36754,903,0}; /*num events after cut flow in mathemtatica*/

for(; i < NUM_BG + 1; i++){

cross_section[i] *= 1000; /*convert cross sectionpb to fb*/

num_real_events[i] = cross_section[i] * LUMINOSITY;

printf("%d: num real events is %f\n", i, num_real_events[i]);

printf("weight for mg events is %f\n", num_real_events[i] / MADGRAPH_EVENTS);

cut_efficiency[i] = cut_events[i] / MADGRAPH_EVENTS; /*effiency = cut events (real events) / simulated events*/

sg_and_bgs[i] = cross_section[i] * LUMINOSITY * cut_efficiency[i]; /*cross-section*luminosity*cut_efficiency*/

printf("sg_and_bgs[%d]: %f\n",i, sg_and_bgs[i]);

}

/*significance = sg_and_bgs[0] / sqrt(sg_and_bgs[0] + sg_and_bgs[1] + sg_and_bgs[2]);

printf("sig is %f\n", significance);*/

return 0;

}

/c file ends

RS MODEL DIAGRAMS

FEYNMAN DIAGRAMS FOR THE CHANNELS I WORKED ON

DISTRIBUTIONS OF INVARIANCES I CUT ALONG (FROM 04/28/18 POST)

blue is always signal, green is always background, orange is always same background with one jet-faking-photon

RESULTS AT THE END OF ALL THIS (FROM 04/28/18 POST)

__________________________________________________________________

05/22/18

I want to try my hand at rewriting the Mathematica code. It was a bottleneck in the research process because it limited my analysis time to whatever local machine I had Mathematica on. I want to at least implement the analysis for the triphoton channel in python so that the code can be run on the cluster. I will be using cut parameters similar to those from my 04/28/18 runs. I will only work with 1 run of 500 events for each process and compare results from my python code and the original Mathematica code for reference. Attached to this page are the condor command files for each process. I had to attach them with txt extensions because Google Pages would not allow the cmd extension.

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