Another week passed and as promised, I sat down in front of my computer and worked on the remaining part of the simulations for the fifth installation of Citizen Science on Hive. The goal of the Citizen Science project being led by @lemouth is to conduct a particle physics study on neutrino mass model at CERN's Large Hadron Collider (LHC). The simulated collisions we produce using MadGraph5 is composed of the signal well hidden in background events. In our current task, we focus on the simulation of the neutrino signal we aim to study. In the future, our goal is to design a selection strategy to determine whether a given event is kept or rejected, this will be dependent on the calculations of the event properties performed.
To move forward with this goal, we first manage to reproduce the plot from our reference scientific article. At CERN, one of the experiments being conducted involve the colliding of two protons. Our concern are the constituent particles of these protons: the quarks . As these quarks are accelerated close to the speed of light, there's a given probability that these particles emit a W boson being sensitive to weak interactions. We are then interested in the new physics that happens as a consequence, the two emitted W bosons exchange a heavy neutrino N, that leads to the production of two leptons of the same electric energy. In the our reference paper, it covers the scope of the production of two muons or two antimuons.
I was able to write my progress report covering the calculations of the signal production rate at 13 TeV which corresponds to the collision energy of LHC Run 2. My previous result used neutrino mass values from 50 GeV to 10,000 GeV. The plot I was able to produce seems to follow the trend of the results from the reference paper. However, following the values from this post by @lemouth, I considered a different range of neutrino masses for the simulations. And for the remaining part of the simulations, we considered the collision energy of 13.6 TeV which corresponds to the LHC Run 3 that began a few weeks ago.
As observed in the figures above, there is not much difference between the plot for the two collision energies considered. However, from the table below, the corresponding cross section values of the neutrino mass values are different for the simulation results of 13 TeV and 13.6 TeV.
Signal rate dependence on the neutrino mass at 13 TeV
| Neutrino mass (GeV) | Cross section (fb) |
|---|---|
| 50 | 3.5584 |
| 100 | 7.9337 |
| 150 | 11.2581 |
| 250 | 14.8646 |
| 500 | 16.1257 |
| 1,000 | 12.3694 |
| 2,500 | 4.9459 |
| 5,000 | 1.7002 |
| 10,000 | 0.4854 |
| 20,000 | 0.1254 |
Signal rate dependence on the neutrino mass at 13.6 TeV
| Neutrino mass (GeV) | Cross section (fb) |
|---|---|
| 50 | 3.8313 |
| 100 | 8.6255 |
| 150 | 12.1733 |
| 250 | 16.2331 |
| 500 | 17.9871 |
| 1,000 | 13.9182 |
| 2,500 | 5.7143 |
| 5,000 | 2.0001 |
| 10,000 | 0.5758 |
| 20,000 | 0.1505 |
For this task, the simulation run took almost 2hrs since there were 20 runs in total performed. As everything is highly automated, aside from setting the parameters of the process, the output produced is only around 37mb.
That's it for the fifth installation of Citizen science project, as there will be a three week time off. I hope that I could use it to catch up on the reading materials related to what we are working on. :) And if this picked your interest on learning about particle physics. Feel free to join us! ✨
I applaud you. Although I cannot do any of the computer work entailed here, I find the whole concept of citizen scientist exciting. You, @lemouth and the other participants are making history. I'll try to follow your progress when the three weeks are up and @lemouth returns from a well-needed vacation.
Thank you for your kind words. :) Yeah, it really is exciting how the project is progressing as this is my first collaborative work on the chain.
Finally, I have found the time to check out this report. Sorry for being so late on it. It was a bad timing, with me disappearing for vacation and having less time than expected before leaving for Canada. Anyway, I am back and thanks to @gwajnberg, I remembered that I didn't comment this blog. Today I fix this, with two comments.
First of all, congratulations for having achieved all the tasks. The plots you have shared are beautiful. Note that you may want to add units (fb) on the Y-axis to make them perfect.
Second, I would like to comment on this:
This shows that there is a gain in reach with every little increase in collision energy. All production rates get larger, so that rare events become slightly less rare. On the other hand, background becomes also more frequent, so that there is no free lunch.
Please note that in case you missed it, I released episode 6 earlier today. I am confident that you will be able to go through it very quickly) :)
Cheers!
Thanks for the comments, I'd add the unit when I redo the plots. This a gentle reminder for me to read through my progress reports before I take on the next tasks for the episode 6, which is a perfect activity for this coming weekend. :)
Does this implies that there's a negative consequence with higher collision energy in terms of having more frequent background. But on the good side, the processes were are interested becomes more occurrent?I am thus looking forward to read your report at some point next week. Feel free to ask questions if needed (although I am sure this is a natural extension of what you have already done so far, so that there may just be no question at all).
More background does not necessarily mean more background with properties mimicking those of a signal. Each analysis at the LHC performs a selection of relevant events. This targets as many signal events as possible, and as few background events as possible. In general, once the full analysis is implemented, even if the background rates increase by a lot, the number of selected signal over the number of selected background events may stay favourable to us (although the analysis may need refinements to get better background rejection).
Does it clarify?
Cheers!
Ohh, that explains clearly to me. And that's the work (designing the analysis and selection rules) we're doing, right? By the way, I re-plot the figures above, incorporating the addition of [fb] units to the y-axis label.
For the 13 TeV:
And for the 13.6 TeV:
This is the work we will do once signal and backgrounds will be both simulated. Note that we will not perform the study blindly as I have good ideas of where to go, but there are parameters of the analysis that will have to be determined.
Thanks also for the new plots. It is unfortunately too late to include one of them in my presentation at HiveFest (because I was too pushed for time). However, one of those in the previous version appears (together with your name) ^^
Cheers!
Wonderful job in the report
!1UP
Click this banner to join "The Cartel" discord server to know more.
Thank you for the support! :)
You have received a 1UP from @gwajnberg!
@stem-curator, @vyb-curator, @pob-curator, @neoxag-curator
And they will bring !PIZZA 🍕.
Learn more about our delegation service to earn daily rewards. Join the Cartel on Discord.
Thanks for your contribution to the STEMsocial community. Feel free to join us on discord to get to know the rest of us!
Please consider delegating to the @stemsocial account (85% of the curation rewards are returned).
You may also include @stemsocial as a beneficiary of the rewards of this post to get a stronger support.
Your content has been voted as a part of Encouragement program. Keep up the good work!
Use Ecency daily to boost your growth on platform!
Support Ecency
Vote for new Proposal
Delegate HP and earn more
Thank you for the support @ecency team! :)
Congratulations @travelingmercies! You have completed the following achievement on the Hive blockchain and have been rewarded with new badge(s):
Your next target is to reach 39000 upvotes.
You can view your badges on your board and compare yourself to others in the Ranking
If you no longer want to receive notifications, reply to this comment with the word
STOPCheck out the last post from @hivebuzz: