EPE Data Science Workshop Summer 2021

US/Pacific
Description

This is a Virtual Event for students whom are interested in exploring particle physics research in the summer quarter. Hsu's team will lead a series of hands-on exercises with participating students during this two weeks period. Students could either join the full period of the activity or partial events. Beginning students can work on Computing Tutorials, and advanced students can work on either advanced tutorials (MadGraph analysis, Machine Learning) or join other senior students to work on one of the research topics. Successful students can extend the project after the workshop to earn PHYS499 credits or develop it further into a complete research program.

Time: 4pm~6pm (PDT) June 14-25

Details of the tutorials can be found here:

Overview document 

References:

    • 16:00 16:30
      Computing Tutorial 30m
      Speaker: Haoran Zhao (University of Washington (US))

      00:08:14    Shih-Chieh Hsu:    It will be useful to share screen.
      00:10:00    Shih-Chieh Hsu:    why don’t we read manual now
      00:10:13    Shih-Chieh Hsu:    Can you type the command again
      00:10:22    Shih-Chieh Hsu:    it only has 5 options.
      00:10:28    Shih-Chieh Hsu:    Read it and let us know what you think.
      00:10:41    Shih-Chieh Hsu:    not so many. just a few options
      00:10:52    Shih-Chieh Hsu:    Beverly
      00:10:55    Shih-Chieh Hsu:    what do you think?
      00:10:59    Shih-Chieh Hsu:    after reading the manual
      00:11:07    Shih-Chieh Hsu:    Anyone else can comment
      00:11:49    Shih-Chieh Hsu:    You can also google this command
      00:11:50    Shih-Chieh Hsu:    https://linux.die.net/man/1/wc
      00:13:06    Shih-Chieh Hsu:    Beverly, you asked about what Standard Output is
      00:13:14    Shih-Chieh Hsu:    Remember, Google is our good friend
      00:13:15    Shih-Chieh Hsu:    http://www.linfo.org/standard_output.html
      00:13:24    Beverly Shih:    Thank you
      00:13:57    Kaylin Ingalls (She/her):    I can’t talk out loud but I am in the middle of the shell one
      00:14:00    Riley Maloney:    for the shell notebook should I be working in the normal terminal, PowerShell, … (on windows)
      00:14:02    Kaylin Ingalls (She/her):    No questions
      00:14:13    Kaylin Ingalls (She/her):    :) sorry about not being able to be unmute
      00:14:44    Shih-Chieh Hsu:    you need to use linux environment in Windoes
      00:14:46    Riley Maloney:    alright hahaha I was wondering why I couldn't do a lot of stuff
      00:14:59    Haikun Xue:    do I need a Linux vm for it?
      00:15:03    Shih-Chieh Hsu:    All the exercise here is using Linux shell
      00:15:19    Shih-Chieh Hsu:    You can install docker container to get linux shell
      00:15:32    Alexandre Ramirez:    how do u use ls to select all data containing a or b?
      00:15:42    Randall Scarborough, RSA, 5:    the docker instructions were clear and easy for me to get bash working
      00:17:49    Shih-Chieh Hsu:    Bevelyn, are you using Mac OS?
      00:18:04    Shih-Chieh Hsu:    The MacOS has no -L option for wc command
      00:18:20    Shih-Chieh Hsu:    Again, google is our good friend. Check this post:
      00:18:21    Shih-Chieh Hsu:    https://stackoverflow.com/questions/1655372/longest-line-in-a-file
      00:18:25    Haikun Xue:    so all the notebooks are on Linux?
      00:18:51    Shih-Chieh Hsu:    exactly speaking, all the exercise should be done on shell
      00:18:57    Shih-Chieh Hsu:    either bash shell or tcsh
      00:19:02    Haikun Xue:    ok
      00:19:06    Shih-Chieh Hsu:    You can use Google Colab
      00:19:42    Shih-Chieh Hsu:    Yes
      00:20:18    Shih-Chieh Hsu:    https://stackoverflow.com/questions/59318692/how-can-i-run-shell-terminal-in-google-colab
      00:21:31    Riley Maloney:    I just realized I have Ubuntu on my windows, will that work in place of docker
      00:22:17    Haoran Zhao:    WSL on windows
      00:23:47    Alexandre Ramirez:    What command do u need to do to answer this question? Does it involve /./? List all of the files in /bin that contain the letter a or the letter b
      00:26:12    Shih-Chieh Hsu:    Can Alexandre Ramirez share the screen?
      00:28:27    Alexandre Ramirez:    Thank you!
      00:29:02    Shih-Chieh Hsu:    Again, google is our good friend
      00:29:03    Shih-Chieh Hsu:    https://geek-university.com/linux/wildcard/
      00:29:17    Shih-Chieh Hsu:    You want to learn more about what wildcard mean in linux system.
      00:30:53    Shih-Chieh Hsu:    To learn more environment variable, check this
      00:30:53    Shih-Chieh Hsu:    https://geek-university.com/linux/environment-variables/
      00:31:30    Randall Scarborough, RSA, 5:    I was able to do that using ls *a*b* *b*a*
      00:31:47    Shih-Chieh Hsu:    yes. that was the answer
      00:32:14    Shih-Chieh Hsu:    All these questions can be discussed in the Discord
       

    • 16:40 17:10
      Introduction of cross section and luminosity 30m
      Speaker: Shao-Chien Ou (University of Washington (US))

      00:33:46    Shih-Chieh Hsu:    Oscar, if no one works on MadGarph tutorial
      00:33:53    Shih-Chieh Hsu:    it’s better to go through min-lecture
      00:33:56    Shih-Chieh Hsu:    to talk about physics
      00:34:09    Shih-Chieh Hsu:    e.g. what collider is, cross section is, ….,
      00:34:29    Shih-Chieh Hsu:    I don’t think it’s so useful to show how to run docker
      00:34:36    Shih-Chieh Hsu:    if people don’t try to do hands-on works
      00:36:42    Apurva Goel:    thank you, Professor! Haven’t installed it yet but that’s the next step tonight!
      00:41:05    Haikun Xue:    just curious why did they name the unit "barn"
      00:41:16    Joħn Spencer:    Historical context
      00:41:23    Joħn Spencer:    They said "it was like hitting the broad side of a barn"
      00:41:51    Haikun Xue:    lol thanks
      00:42:02    Riley Maloney:    so physicists got jokes lol
      00:42:12    Joħn Spencer:    Oh yes
      00:43:48    Kaylin Ingalls (She/her):    XD Gotta love physics names.
      00:44:30    Beverly Shih:    Can you explain why it doesn’t make sense in the quantum limit
      00:45:12    Shih-Chieh Hsu:    This is a good question!
      00:47:14    Beverly Shih:    Ok thanks
      00:48:14    Shih-Chieh Hsu:    Good questions!
      00:50:42    Alexandre Ramirez:    The target is another particle right?
      00:53:19    Shih-Chieh Hsu:    sigma = area = effective interaction strength,  Omega = angle = (theta, phi) = (polar angle, azimuthal angle) in Spherical coordinate
      00:56:07    Shih-Chieh Hsu:    Good questions!
      01:04:29    Shih-Chieh Hsu:    what is science method?
      01:05:00    Shih-Chieh Hsu:    excellent
      01:08:45    Kaylin Ingalls (She/her):    That condensed explaination was very helpful, thank you.
      01:08:45    Apurva Goel:    thank you!! that was helpful!
      01:11:44    Shih-Chieh Hsu:    define what one event is
      01:12:42    Haikun Xue:    can you elaborate a bit?
      01:13:05    Haoran Zhao:    Proton proton
      01:13:56    Shih-Chieh Hsu:    every proton proton collision is one event.
       

    • 17:20 17:50
      FASER 30m
      Speaker: John William Spencer (University of Washington (US))

      01:21:08    Alexandre Ramirez:    What is CP
      01:23:22    Haikun Xue:    does neutrino link to cp violation?
      02:07:38    Kaylin Ingalls (She/her):    Thank you! This was awesome!! Very well done!!
      02:07:49    Alexandre Ramirez:    Thank you!
      02:11:04    Apurva Goel:    thank you guys!
      02:11:08    Sean:    Thanks!
       

    • 16:00 16:30
      Computing Tutorial 30m
      Speaker: Haoran Zhao (University of Washington (US))

      00:34:32    Riley Maloney:    we can see it, can you hear us?
      00:34:35    Haikun Xue:    can you hear us?
      00:34:41    Alexandre Ramirez:    yes
      00:34:41    Shih-Chieh Hsu:    yes. we can see it.
      00:34:44    Haoran Zhao:    nope...
      00:34:57    Shih-Chieh Hsu:    we can hear you
      00:34:59    Haoran Zhao:    anyone speaking? 
      00:38:41    Haikun Xue:    ls *a**b*
      00:50:15    Kevin Jiarui Wang:    I have a question. Is the "shell directory" just what folder the shell is looking at right now, or is it a specific directory?
      00:52:26    Joħn Spencer:    Question: How do you search for a string in a file?
      00:53:26    Kevin Jiarui Wang:    Thanks
      01:01:00    Shih-Chieh Hsu:    In terms of setting up environment, there is a difference between tcsh and bash shell.  Pay attention on which shell you are using.
      01:02:59    Shih-Chieh Hsu:    vi
      01:03:07    Shih-Chieh Hsu:    are you using text editor: vi?
      01:04:14    Shih-Chieh Hsu:    you are using: vim
      01:04:18    Haoran Zhao:    vim
      01:04:21    Haoran Zhao:    apt install vim 
      01:04:42    Haoran Zhao:    vim text editor
      01:04:57    Shih-Chieh Hsu:    For everyone, please indicate your current progress in this google spreadsheet  https://docs.google.com/spreadsheets/d/1fX6O2uA3zn4FcsdCiCxhtiymYWTG6QH8idla-fBiF2g/edit#gid=0
      01:13:02    Alexandre Ramirez:    Where can we see these recordings?
      01:13:11    Joħn Spencer:    indico page
      01:16:08    Shih-Chieh Hsu:    slides and recording are available
      01:16:09    Shih-Chieh Hsu:    https://indico.cern.ch/event/1046620/

    • 16:40 17:10
      Standard Model introduction 30m
      Speaker: Shao-Chien Ou (University of Washington (US))

      01:22:57    Shih-Chieh Hsu:    For those of you whom are new to particle physics, you can explore this website: https://particleadventure.org/
      01:23:41    Shih-Chieh Hsu:    You will hear many jargons of particle physics to work on projects in this research team. You are encouraged to explore and ask questions.
      01:23:57    Alexandre Ramirez:    Yeah I have been watching PBS space time for an introduction
      01:24:18    Shih-Chieh Hsu:    coo. you can share this nice PBS video with the team.
      01:24:18    Joħn Spencer:    PBS space time is good, but beware Matt also uses a lot of jargon
      01:24:35    Joħn Spencer:    "PBS video" - PBS space time is actually a YouTube channel
      01:26:32    Alexandre Ramirez:    I'm not sure which videos I watched, I will share in the discord when I can
      01:28:37    Shih-Chieh Hsu:    John, can you clone this google slide and edit a correct version.
      01:30:00    Haikun Xue:    that's pretty cool
      01:30:28    Shih-Chieh Hsu:    John, I think we have slightly different understanding of the notation
      01:30:47    Shih-Chieh Hsu:    To me, the right hand side diagram is correct
      01:30:56    Shih-Chieh Hsu:    The left hand side diagram was wrong
      01:32:28    Shih-Chieh Hsu:    https://en.wikipedia.org/wiki/Feynman_diagram
      01:33:40    Shih-Chieh Hsu:    https://arxiv.org/pdf/1602.04182.pdf
      01:33:46    Shih-Chieh Hsu:    Chapter 6 as example
      01:34:50    Yi-Lun (Alan):    I think we can just use direction to say whether incoming particles or outgoing particles are particle or anti-particles.
      01:36:20    Shih-Chieh Hsu:    When a particle line go against time direction, it’s an anti-particle
      01:36:30    Shih-Chieh Hsu:    it’s the simple rule
      01:36:58    Joħn Spencer:    "When a particle line go against time direction, it’s an anti-particle" - This is what I was saying
      01:37:55    Shih-Chieh Hsu:    https://www.quantumdiaries.org/2010/02/14/lets-draw-feynman-diagams/
      01:37:55    Apurva Goel:    what is the current question?
      01:39:59    Shih-Chieh Hsu:    I have a different interpretation of the t-channel diagram. There are no new particles created. It’s particle A and particle B exchange a particle with momentum J.
      01:40:41    Alexandre Ramirez:    what is meant by t-channel diagram? how do I recognize one
      01:40:43    Shih-Chieh Hsu:    The s-channel, there are indeed new particle created.
      01:41:06    Shih-Chieh Hsu:    Oscar, you can explain t-ch and s-ch again.
      01:41:58    Shih-Chieh Hsu:    https://en.wikipedia.org/wiki/Mandelstam_variables
      01:43:14    Alexandre Ramirez:    I understand thank you
      01:43:21    Shih-Chieh Hsu:    In s-channel, we stated that   q and q-bar annihilate into a photon, which further decays to electron positron pair
      01:43:42    Shih-Chieh Hsu:    yes.
      01:43:52    Shih-Chieh Hsu:    Very good obersrvation
      01:44:01    Shih-Chieh Hsu:    That is the beauty of Feynman Diagram
      01:44:14    Shih-Chieh Hsu:    The t-channel is a scattering process
      01:44:28    Shih-Chieh Hsu:    The s-channel is a creation/decay process
      01:44:44    Shih-Chieh Hsu:    In Quantum Field Theory, s-ch and t-ch are actually identical
      01:44:57    Shih-Chieh Hsu:    It’s all about how you interpret them w.r.t. time arrow
      01:47:00    Shih-Chieh Hsu:    https://docs.google.com/spreadsheets/d/1fX6O2uA3zn4FcsdCiCxhtiymYWTG6QH8idla-fBiF2g/edit#gid=0
       

    • 17:20 17:50
      Boosted Higgs classification 30m
      Speakers: Yi-Lun Chung (Academia Sinica (TW)), Yi-Lun Chung (National Tsing Hua University (TW))

      01:57:35    Alexandre Ramirez:    how do I acces the archive?
      01:58:09    Shih-Chieh Hsu:    Which archive?
      01:58:15    Shih-Chieh Hsu:    the slide and recording?
      01:58:17    Alexandre Ramirez:    to see his work
      01:58:21    Shih-Chieh Hsu:    oh
      01:58:26    Shih-Chieh Hsu:    just click the link
      01:58:41    Beverly Shih:    https://arxiv.org/abs/2009.05930
      01:59:07    Haikun Xue:    I don't think the slides are up yet
      02:00:32    Haikun Xue:    thanks
      02:04:56    Haikun Xue:    why are they massless from the equation?
      02:08:52    Haikun Xue:    ok will check out thanks
      02:16:21    Kaylin Ingalls (She/her):    how can a higgs decay into something with more mass than it has? Like, how is a higgs with mass smaller than 2* the mass of a w boson able to decay into two w bosons?
      02:18:40    Haikun Xue:    so the mass of Higgs boson does not vary?
      02:19:43    Kaylin Ingalls (She/her):    ahhh that makes sense, thanks!
      02:20:35    Shih-Chieh Hsu:    Really?
      02:20:42    Shih-Chieh Hsu:    How about off-shell Higgs boson
      02:21:24    Shih-Chieh Hsu:    You need to introduce Resonance concept
      02:25:07    Shih-Chieh Hsu:    https://www.cpp.edu/~pbsiegel/phy40413/lectures/lecture10.pdf
      02:25:48    Shih-Chieh Hsu:    on-shell means at the mass peak value
      02:25:58    Shih-Chieh Hsu:    off-shell means not at the mass peak value
      02:26:22    Shih-Chieh Hsu:    http://physik.uibk.ac.at/hephy/bachelor/Higgs/HowToFindANewParticle.pdf
      02:27:31    Apurva Goel:    those are nice links! thank you, Prof.!
      02:27:43    Alexandre Ramirez:    ^
      02:29:19    Alexandre Ramirez:    what is a fermion loop?
      02:34:06    Apurva Goel:    can there even be a higgs jet?
      02:35:44    Apurva Goel:    ok. thanks.
      02:36:27    Kaylin Ingalls (She/her):    what is the ghost association method?
      02:39:17    Shih-Chieh Hsu:    https://iopscience.iop.org/article/10.1088/1742-6596/645/1/012008/pdf
      02:39:28    Kaylin Ingalls (She/her):    thank you!
      02:51:13    Kaylin Ingalls (She/her):    Thank you!! that was very interesting!
      02:51:38    VAN THA BIK LIAN:    thank you!
      02:51:54    Haikun Xue:    Thanks
      02:52:09    Shih-Chieh Hsu:    https://indico.cern.ch/event/1046620/
       

    • 16:00 16:30
      Computing Tutorial 30m
      Speaker: Haoran Zhao (University of Washington (US))

      00:16:36    Haoran Zhao:    https://stackoverflow.com/questions/37937984/git-refusing-to-merge-unrelated-histories-on-rebase
      00:16:46    Haoran Zhao:    --allow-unrelated-histories
      00:18:09    Haoran Zhao:    git pull origin master --allow-unrelated-histories
      00:25:34    Haoran Zhao:    sudo apt install vim 
      00:26:21    Haoran Zhao:    
      :q
      00:30:01    Ke Li:    :set nu
      00:40:46    Ke Li:    :wq
      00:45:35    Haoran Zhao:    GUI = Graphical user interface 
       

    • 16:40 17:10
      Feynman Diagram Instroduction 30m
      Speaker: Shao-Chien Ou (University of Washington (US))

      0:46:26    Shih-Chieh Hsu:    Can you first summarize the discussion on Madgraph discord channel?
      01:06:26    Shih-Chieh Hsu:    Excellent! Concept crossed!
      01:08:50    VAN THA BIK LIAN:    can you please quickly go over what a t-channel is and what s-channel is?
      01:09:14    Shih-Chieh Hsu:    Notation reminder   e-: electron   e+: positron   q-bar: anti-quark  q: quark
      01:11:25    Shih-Chieh Hsu:    left: electron and positron scattering by exchanging a virtual quark
      01:12:02    Shih-Chieh Hsu:    that is right
      01:12:15    Shih-Chieh Hsu:    Sorry for the mistake
      01:12:23    Shih-Chieh Hsu:    the wave should mean a W,Z or a photon
      01:12:41    Alexandre Ramirez:    Why do we not distinguish between W ,Z and a photon?
      01:12:52    Shih-Chieh Hsu:    We need to label them
      01:13:12    Shih-Chieh Hsu:    it’s just too much  to design the cartoon
      01:13:19    Alexandre Ramirez:    ok
      01:13:49    Shih-Chieh Hsu:    right: positron and electron annihilates to gauge boson (W,Z,gamma), and gauge boson decays to electron-positron pair
      01:15:28    Joħn Spencer:    Actually W is not possible (charge=+-1)
      01:15:39    Shih-Chieh Hsu:    Yes. It’s not possible in this case
      01:15:47    Shih-Chieh Hsu:    It can only be Z*/gamma
      01:15:54    Shih-Chieh Hsu:    in this particular case
      01:16:04    Joħn Spencer:    Yes, agreed.
      01:17:04    Shih-Chieh Hsu:    Yes. Mathematical expression :)
      01:17:22    Shih-Chieh Hsu:    Remember, there is an imaginary number in the quantum wave
      01:17:33    Shih-Chieh Hsu:    but the physical world is only real
      01:17:49    Shih-Chieh Hsu:    Before we move on. Let’s do a round table tutorial progress update: https://docs.google.com/spreadsheets/d/1fX6O2uA3zn4FcsdCiCxhtiymYWTG6QH8idla-fBiF2g/edit#gid=0
      01:21:44    Shih-Chieh Hsu:    BTw, you don’t have to study systematics
      01:21:58    Shih-Chieh Hsu:    I notice the default setting enable the systematic variation
      01:22:11    Shih-Chieh Hsu:    you can change MadGraph configuration to disable PDF uncertainties

    • 17:20 17:35
      Photon-jet 15m
      Speaker: Ke Li (University of Washington (US))

      01:25:40    Shih-Chieh Hsu:    There are many non-trivial and abstract concept in fundamental particle physics. It’s good to review the same concept multiple times in order to reinforce learning and eventually understand the concept.
      01:36:44    Alexandre Ramirez:    What is a Lorentz boost?
      01:53:06    Shih-Chieh Hsu:    http://www.phys.ufl.edu/~avery/course/4390/f2015/lectures/relativistic_kinematics_2.pdf
      01:59:47    Shih-Chieh Hsu:    https://particleadventure.org/color.html
      02:03:39    Shih-Chieh Hsu:    https://math.ucr.edu/home/baez/physics/ParticleAndNuclear/gluons.html
      02:15:16    Apurva:    Really appreciate the effort put into the slides though!!
      02:15:23    Apurva:    Thank you guys!!
      02:15:26    Kaylin Ingalls (She/her):    This was very interesting! thank you!!
      02:15:35    Alexandre Ramirez:    Thank you!
      02:16:37    Apurva:    That makes sense! Thank you , Prof!
       

    • 17:40 17:55
      Vector Boson Scattering Wgamma 15m
      Speaker: Elham E Khoda (University of Washington (US))
    • 16:00 16:30
      Computing Tutorial 30m
      Speaker: Haoran Zhao (University of Washington (US))

      00:09:35    Shih-Chieh Hsu:    https://docs.google.com/spreadsheets/d/1fX6O2uA3zn4FcsdCiCxhtiymYWTG6QH8idla-fBiF2g/edit#gid=0
      00:09:47    Shih-Chieh Hsu:    thanks for updating spreadsheet
      00:14:47    Shih-Chieh Hsu:    make a pull request
      00:15:18    Shih-Chieh Hsu:    thank you. Beverlyn
      00:15:28    Shih-Chieh Hsu:    Zach, you could try :)
      00:15:41    Shih-Chieh Hsu:    No.
      00:15:53    Shih-Chieh Hsu:    No
      00:16:09    Shih-Chieh Hsu:    You can go through common issues
      00:16:15    Shih-Chieh Hsu:    on Discord
      00:26:15    Shih-Chieh Hsu:    Whitespace is used to denote blocks. When you indent, it becomes a child of the previous line.
      00:27:22    Shih-Chieh Hsu:    In C++, you use brackets ‘{’ and ’}’ to define blocks.
      00:28:37    Shih-Chieh Hsu:    in C++, whitespace doesn’t mean anything
      00:38:16    Shih-Chieh Hsu:    Mind the version of package. It’s common issues in programming.

    • 16:40 17:10
      MadGraph Tutorial 30m
      Speaker: Shao-Chien Ou (University of Washington (US))

      00:41:26    Shao-Chien Ou:    https://hackmd.io/@D2NCN-LxSNiAK6etDgTKYA/H1dyeyj1D
      00:51:46    Haikun Xue:    must be at rest?
      00:53:57    Shih-Chieh Hsu:    Does everyone understand what a center-of-mass frame is?
      00:54:33    Alexandre Ramirez:    ^ I have forgotten
      00:54:44    Shih-Chieh Hsu:    John, you can edit a slide with cartoon to pose the question.
      00:54:54    Shih-Chieh Hsu:    This can be a homework assignment for discussion next week
      00:55:39    Shih-Chieh Hsu:    I suggest Oscar to move on
      00:59:29    Apurva:    e=mc^2 + p^2 c^2
      00:59:46    Apurva:    sqrooted
      01:00:05    Apurva:    e=mc^2
      01:00:25    Haikun Xue:    e = sqrt (mc^2 + p^2 c^2)
      01:00:36    Haikun Xue:    wait no
      01:00:54    David Lai:    E^2 = (mc^2)^2 + (pc)^2
      01:01:58    Apurva:    ahhh^ haha i missed the square in mc^2
      01:03:11    Zach Marucheck:    I haven’t seen the relativistic equation before so this is helpful
      01:03:30    Shih-Chieh Hsu:    p24 statement is strange
      01:03:43    Shih-Chieh Hsu:    what do you mean “total mass"?
      01:04:03    Haikun Xue:    p = mv right? so it only matters when v is close to c?
      01:04:22    Shih-Chieh Hsu:    The invariant mass of center-of-mass system is the total energy of the COM system.
      01:04:31    Shih-Chieh Hsu:    I don’t understand the concept of total mass
      01:05:08    Shih-Chieh Hsu:    Invariant mass -> it’s invariant
      01:05:22    Shih-Chieh Hsu:    Can you explain whether M=m1 + m2 ?
      01:05:47    Shih-Chieh Hsu:    Because you said “total mass”
      01:05:52    Shih-Chieh Hsu:    mass of particle 1 is m1
      01:05:55    Shih-Chieh Hsu:    mass of particle 2 is m2
      01:06:02    Shih-Chieh Hsu:    so, total mass is M=m1+m2
      01:06:12    Shih-Chieh Hsu:    This is my interpretation of your statement
      01:06:17    Shih-Chieh Hsu:    No. That is fine
      01:06:24    Shih-Chieh Hsu:    It’s the last statement wrong
      01:06:48    Shih-Chieh Hsu:    The invaraint mass is the “total energy” of the center-of-mass system
      01:06:58    Shih-Chieh Hsu:    Can you explain the reason?
      01:07:45    Shih-Chieh Hsu:    Good. My next question, in which case, M=m1+m2?
      01:08:20    Shih-Chieh Hsu:    it’s more than just center-of-mass frame
      01:08:25    Shih-Chieh Hsu:    you need one more condition
      01:08:39    Shih-Chieh Hsu:    May I suggest a breakout room discussion
      01:08:51    Shih-Chieh Hsu:    Can I edit this slide?
      01:09:00    Shih-Chieh Hsu:    Send us the google slide
      01:09:09    Shao-Chien Ou:    https://docs.google.com/presentation/d/1R9x9xJ9DZl8LMEP4kSXNXnOG4ohToyW4HB3EZ4riSws/edit#slide=id.ge00e65cf31_0_99
      01:21:37    Shih-Chieh Hsu:    Excellent answer!
      01:23:26    Shih-Chieh Hsu:    mathematically, it means p1=0, p2=0,
      01:23:45    Shih-Chieh Hsu:    particle1, particle2 are at rest :)

    • 17:20 17:40
      Calorimeter Clustering with SPVCNN 20m
      Speaker: Alexander Joseph Schuy (University of Washington (US))

      01:26:13    Shih-Chieh Hsu:    I can’t talk loud
      01:26:18    Shih-Chieh Hsu:    anyone else can comment
      01:27:08    Shih-Chieh Hsu:    people get lost in Ke’s talk
      01:27:17    Shih-Chieh Hsu:    it’s good to talk more about what calorimeter is
      01:33:43    Alexandre Ramirez:    what is a scintillator
      01:35:18    Apurva:    cool plot!
      01:39:51    Shih-Chieh Hsu:    Scintillator is used in the PET tomography https://en.wikipedia.org/wiki/Positron_emission_tomography
      01:41:03    Shih-Chieh Hsu:    Check this animation about two proton accelerated by the LHC and collides in the center of ATLAS
      01:41:03    Shih-Chieh Hsu:    https://www.youtube.com/watch?v=AHT9RTlCqjQ
      01:41:41    Haikun Xue:    cool video
      01:41:57    Beverly Shih:    Thanks for the video
      01:49:54    Haikun Xue:    how do you decide how many hidden layers to use?
      01:50:17    Apurva:    i suppose that’d depend on the model you’re training?
      01:50:56    Haikun Xue:    so you would know some underlying pattern before setting up the program?
      01:51:45    Apurva:    is there an accuracy trade-off with convolutional neural networks?
      01:54:06    Apurva:    ok, interesting.. then what is the performance/running-time tradeoff between these algorithms?
      01:58:10    Haikun Xue:    What can we learn from the cluster patterns?
      01:58:19    Apurva:    cool!! thank you for this brief but fun intro!
      02:00:19    Haikun Xue:    thanks!
      02:00:45    Apurva:    what are some of the coolest applications of machine learning in particle physics that you’ve heard of?
      02:00:49    Kaylin Ingalls (She/her):    thanks! This was great!
      02:02:57    Shih-Chieh Hsu:    The coolest application of ML on particle physics so far - I would say it is the Higgs boson discovery in 2012 which leads to Nobel Prize in 2013
      02:03:06    Apurva:    Absolutely!! thanks so much for sharing!
      02:03:41    Morgan Cassidy:    Thanks!
       

    • 16:00 16:30
      Computing Tutorial 30m
      Speaker: Haoran Zhao (University of Washington (US))
    • 16:40 17:10
      Machine Learning Tutorial 30m
      Speaker: Ajay Rawat (University of Washington (US))
    • 17:20 17:50
      Search for monoSbb and VBS Zgamma 30m
      Speaker: Qibin Liu (Tsung-Dao Lee Institute (CN) & Shanghai Jiao Tong University (CN))