June 21 - 25, 2021. Virtual, UNAM (Mexico) and IU (USA)
aszczepa
2021-06-15 17:48
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aszczepa
2021-06-15 17:48
@aszczepa set the channel description: National Nuclear Physics Summer School
 
aszczepa
2021-06-15 17:50
There should be a way to add all the participants all at once ?
 
cefera
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tpapenbr
2021-06-15 17:57
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tpapenbr
2021-06-15 17:59
Hello everyone
 
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2021-06-15 18:25
This message was deleted.
 
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libertad
2021-06-15 19:08
Hello everyone. Thanks for proposing this, it's a great idea
 
cefera
2021-06-15 19:12
If you are the admin you can create an invitation link. You need to go to the admin tools and click in some invitation green button (sorry I have my slack in Spanish, so I do not know exact wording). A window should pop out to invite people. There should be a "create invitation link option". Copy it and send the link to the mailing list.
 
cefera
2021-06-15 19:14
Hi. Everyone. I am going to post and pin the links to the google calendar and the Zoom registration
 
 
cefera
2021-06-15 19:15
 
libertad
2021-06-15 19:45
Hi, this is the link to invite people to join slack
 
 
je.perez43
2021-06-18 21:29
Hello everybody :slightly_smiling_face:
 
giha
2021-06-18 21:29
Hi! How are you?
 
bem4r
2021-06-19 19:01
Hello everyone!
 
jeannierangel
2021-06-20 16:26
Hello people.
 
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sshainporuve
2021-06-20 18:23
Hello everyone
 
chun-jian.zhang
2021-06-20 18:24
hello, everyone, how is going
 
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cefera
2021-06-20 19:05
please check the pinned messages with the info on the google calendar and the registration link for Zoom
 
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abhay.deshpande
2021-06-20 19:15
Hi All, look forward to meeting you tomorrow on Zoom.
 
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fbergabo
2021-06-20 20:00
Hi Everyone! I'm looking forward to the summer school :slightly_smiling_face:
 
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cefera
2021-06-20 22:29
Dear all. Please note that we have changed a bit the schedule on Friday 25. The Google calendar is updated and displays the correct schedule. Sorry for any inconvenience.
 
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cefera
2021-06-21 12:46
Please, post questions here and use it for discussion!
 
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rajesh.sism
2021-06-21 13:37
@wsnow in zoom chat you said, the number of particles in GCE(mu,V,T) are not conserved. Can you please elaborate about the conversation of chemical potential? And the link between particle # and mu.
 
wsnow
2021-06-21 13:40
the chemical potential is defined to be the change in the energy of the system as one adds a particle to the system, at constant entropy
 
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wsnow
2021-06-21 13:41
so there is no ?conservation? of the chemical potetntial: rather there is conservation (or not) of particle number
 
rajesh.sism
2021-06-21 13:47
Thanks for the reply. But i did not understand the non conservation of chemical potential in Grand canonical ensemble. By definition, mu V T should be constant in the GCE. Pardon me if i am missing something
 
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2021-06-21 13:48
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jbarrow
2021-06-21 13:51
Are any of the lectures being recorded? I came late, sorry
 
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wsnow
2021-06-21 14:04
the chemical potential is not ?conserved?: it is an energy associated with the cost of adding or subtracting a particle from a thermo system. The concept of ?conservation? is associated with the particle number, not the chemical potential
 
rajesh.sism
2021-06-21 14:05
Okay. I was thinking all wrong. Thanks for the clarification.
 
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albertojg12
2021-06-21 14:13
@tpapenbr Hello! I had a quick question about your EFT slide. For NLO onward at NN, are the diagrams that have pion exchanges starting at one point and ending at two considered one-pion exchange or two-pion exchange? If they are one-pion exchange, what does it mean for it to start at one point and end at two. If they are two-pion exchange, is there a reason why there is no longer a one-pion exchange diagram at NN for NLO onward?
 
tpapenbr
2021-06-21 14:31
where we see two dashed lines, we think about them as two-pion exchange, independent of whether they end/start in the same point or in different points
 
libertad
2021-06-21 14:42
Most lectures are being recorded, except those in which the lecturers opted out
 
libertad
2021-06-21 14:53
Here the slides of the lecture on Nuclear Matter (part 1) by @tpapenbr
 
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maianh
2021-06-21 15:12
thank @libertad for your sharing the file.
 
libertad
2021-06-21 15:13
you are welcome!
 
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albertojg12
2021-06-21 16:58
Here were Dr. Ayala?s answers to some of the questions in the chat (he accidentally direct messaged them to me in the zoom chat so I?ll post them here for others). Q - What is the motivation behind using N_c != 3? I?ve never understood why some people choose N_c to be anything besides the real-world value, is it perhaps to connect to some technicolor or unifying theory? A - ?There are several reasons to speak in general about Nc. In the context of a general gauge theory ?Nc? stands for the number of ?charges?; for QCD these are 3 color charges. However, think of the electroweak sector that involves in tow ?weak isospin charges?; in this case ?N_c=2". So when thinking of a general field theory based in a non-Abeliag group it is useful to thinc of Nc to be generañ In the case of QCD , another interesting limit is of course to think theoretically in the case that Nc is large: this is the large Nc limit where one can do approximations to also extract general features of the interaction that help to understand its properties? Q - What?s the best way of thinking about axial flavor symmetry/transformations? I?ve only seen the math for it, but don?t have a good intuition about what it means. A - ?Once we have a the QCD Lagrangian in the massless limit, one can ask oneself what are symmetries. As you can see from the lecture, these symmetries involve vector rotations (only gamma_mu) but also an ?axial vector rotations? (gamma_mu gamma_5). The physical content becomes clearer when you male the combinations gamma_mu(1\pm gamma_5) whose eigenvalues, called chirality, coincide with those of the helicity operator for massless quarks.?
 
cefera
2021-06-21 16:58
Thanks a lot!
 
aszczepa
2021-06-21 17:02
Also, when N_c \to infty QCD becomes special. One can (relatively easy) show that in this limit resonances like rho mesons or Delta baryons etc. become stable.
 
gdaleg2
2021-06-21 17:30
will these lecture be posted today? or later in the week? I also joined late and would like to catch up before tomorrow if possible. Thanks!
 
victor1montesinos
2021-06-21 17:36
I don't know if this has already been said, but where will we get access to today's recording of the lectures?
 
jbarrow
2021-06-21 18:14
Might I recommend a school-related YouTube channel with unlisted (nonpublic) videos?
 
cefera
2021-06-21 18:21
We are recording the lectures of those speakers who have granted permission and will be made, at least, available to the students. Please, understand that there are copyright, permissions and licensing issues associated to posting the lectures online. We have to comply with both UNAM, IU and NSF rules before doing so.
 
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gleckenby
2021-06-21 18:43
Thanks @libertad for sharing the first set of slides. Is it possible to have the full set of slides for each lecture available? I find it really helpful to be able to bounce back and forth between slides whilst the lecturers are talking so I can check what came before.
 
libertad
2021-06-21 20:21
sure, when we get the complete set of slides we can put them together :slightly_smiling_face:
 
libertad
2021-06-21 20:22
Here the slides of the lectures of @ayala
 
cefera
2021-06-21 21:56
Please find enclosed today's Zoom chat (do not mind time tag). 01:52:36 FELIX NDAYISABYE: Thanks for recording this rectures 02:09:40 Angel Nava: Can someone clarify the ?A? in p/A please? 02:09:59 Todd Mendenhall: proton or nucleus of mass number A I think 02:11:02 Filip Bergabo: Yes, A = 1 is a proton. A = 2 is deuteron, etc... 02:11:57 Angel Nava: I see so the p is actually the momentum and does not represent the proton, thanks. 02:12:50 Filip Bergabo: I think p/A in the reaction just means using a proton or a nucleus with A number different than 1. I read p/A as (proton or nucleus) 02:13:15 Todd Mendenhall: yes, emphasis on the OR in p/A 02:14:35 Angel Nava: Okay I think that makes more sense, thanks 02:14:53 Gauri Devi: I think In p-A,A-A collisions, streams of secondary particles ,known as jets are produced. what is cause of increased jet radie ? 02:15:10 Diptanil Roy: ?Inside the quarks"? 02:15:24 Gauri Devi: please sure me what is exact definition of jet? 02:15:24 William Snow: question for Abhay, unless someone else knows? 02:16:37 Manuel Rosales: Jet is just a clustering of particles that result from the collision between quarks that fragment. 02:16:40 Angel Nava: These are beams of particles, I believe that?s what ?jet" refers to but I?m not 100% sure. 02:17:12 Joshua Lin: In particle collision events, high-energy particles fly off from the initial condition and shower (e.g. if you start with a quark quark -> quark quark event, by colour confinement the final state quarks will go on to hadronize into mesons and baryons, in a cone that people call a jet) 02:17:31 William Snow: ?exact definition? of a jet is not quite possible, it is just when the momentum of a cluster of hardons form a high momentum quark or gluon in one direction is large compared to the transverse dimensions. roughly with a longitudinal momentum beyond 1-2 GeV so start to get a ?jet" 02:22:34 Gauri Devi: what is cause of increasing jet radie? 02:22:53 Angel Nava: Thanks for this really descriptive and clear lecture! 02:24:43 Rajesh Kumar: great lecture 02:25:03 Gauri Devi: thanks for this lecture 02:25:26 Omar Alejandro Díaz Caballero: great lecture! 02:26:02 Gauri Devi: It's more beneficial lecture 02:28:28 Joshua Lin: Maybe the spinning top has something to do with eddy currents induced? 02:29:27 William Snow: something like ?eddy currents? is going on inside the proton: some of the proton angular momentum is known to be from the quark orbital angular momentum inside 02:30:13 Joshua Lin: Is this mainly from the valence quarks, or do the sea quarks also somehow contribute to angular momentum? 02:30:58 Debarshi Dey: Is alpha the EM coupling constant or the strong coupling constant? The interaction is between the photon and the quarks? 02:31:00 William Snow: question for Abhay. The answer I think is not yet known for sure 02:31:25 William Snow: yes alpha is EM coupling 02:32:36 William Snow: angular momentum of proton can come from quark spin, quark orbital motion, gluon helicity. all contributions are nonzero and roughly the same size 02:36:57 Debarshi Dey: What exactly is delta_sigma? The difference between which cross-sections? 02:37:11 William Snow: Dear Folks: pdf slides of Thomas Papenbrok?s are in the Slack channel now from Libertad 02:37:39 William Snow: difference between two different spin states of the electron 02:47:11 Angel Nava: Is there a good way to understand or build an intuition for why the baryon density of the sun was close to zero? I guess intuitively I would have expected it to be higher than nuclear matter so I was surprised by that point in the previous lecture. 02:48:02 Debarshi Dey: I;m not clear about the delta sigma yet 02:49:37 sachin shain: Earlier there was a question why the cut off of chiPT is 400 Mev instead of 1GeV, is it because we only consider pions not other mesons? The cut off scale then should be kaon mass around 500 MeV. 02:49:51 William Snow: temperature of the Sun is ?low? only ~few keV in energy units. Energy scale of nucleon bound states is ~MeV. The sun is cold! note that the p-p fusion reactions that burn in the Sun are very slow as they are quantum tunneling through the Coulomb barrier 02:49:54 sachin shain: why is it 400 Mev instead of 500 MeV? 02:50:20 Thomas Papenbrock: In the phase diagram that I showed, density was in units of nuclear density. Compared to that (high) density of about 10^15 g/cm^3, the density at the center of our sun is small (only at about 160 g/cm^3) 02:50:49 Joshua Barrow: Is it understood what the distribution of polarization of the nucleons within the nuclei used within the EIC will be? How are these polarized? 02:51:39 Thomas Papenbrock: A single kaon cannot be exchanged between nucleons because strangeness must be conserved. two-kaon exchange than comes in at 1GeV, which is high 02:52:53 Thomas Papenbrock: There are interactions from chiral effective field theory with many different cutoffs, starting t about 400 MeV and going alll the way to 500 - 600 MeV 02:53:26 sachin shain: okay. Thanks. 02:54:13 Sangyeong Son (Kyungpook National Univ.): the second lightest meson in SU(2) flavor is rho meson so that I understand one must choose the cutoff at least lower than 780 MeV 03:01:03 Abhay Deshpande: Debashri your questions: Is alpha the EM coupling constant or the strong coupling constant? The interaction is between the photon and the quarks? ? if quark is involved, photon is color neutral but can split in to quark-anti-quark pair and those can interact with a gluon ? this is called photon-gluon fusion. The interaction constant involved here is STRONG INTERACTION constant Alpha_S, which is not constant. It depends on Q ? the energy scale. However, if the photon interactions with the quark, which has electrical charge ? then the interaction can be simply electromagnetic. Here the interaction is mediated by a Electromagnetic constant. Alpha_e. Over normal energy regimes (of our world) this is constant?. but on cosmological scales there is evidence that all couplings of all forces unify at certain high energy. Which means that all constants at cosmological scale should ?vary? or ?walk?, to merge in to one another. 03:04:58 Debarshi Dey: Thanks Abhay. So basically it could be both alpha_e and alpha_s? depending on whether the interaction is a photon-gluon fusion or simply a photon-quark interaction. Is that correct? 03:11:05 Abhay Deshpande: Yes, Debashri. Just remember, Alpha_EM is much smaller than Alpha_S (over typical regions of energies that we observe them). So the ?STRONG? interactions are ?strong??. 03:12:21 Debarshi Dey: Okay thanks Abhay for such a descriptive reply. Much appreciated. 03:18:21 Desmond Shangase: What is the motivation behind using N_c != 3? I've never understood why some people choose N_c to be anything besides the real-world value, is it perhaps to connect to some technicolor or unifying theory? 03:22:37 Roland Farrell: I believe it?s to distinguish from N_c = infty (large N). A lot of QCD phenomenology can be understood in large N so it?s a very useful construct. 03:25:50 Desmond Shangase: Thanks for the response. My question is more along the lines of: "why do we entertain large N in the first place?". What was the motivation for allowing N_c to vary to infinity? 03:26:00 Joshua Lin: (General N_c also allows you to write things down like the SU(5) grand unified theory) 03:27:40 Filip Bergabo: I think there's two answers: 1) It's much easier to go from the general case where N_c is general to the case N_c = 3 than to go the other way around. 2) Some QCD calculations simplify a lot if you take the "Large N_c Limit". In this case, you will have only an approximate result, but you simplify your algebra a lot! 03:27:59 Alberto Garcia: What?s the best way of thinking about axial flavor symmetry/transformations? I?ve only seen the math for it, but don?t have a good intuition about what it means. 03:29:25 Desmond Shangase: Thanks @rolanf2, Filip, and Joshua 03:29:45 Filip Bergabo: You're welcome! There's probably other reasons too :) 03:30:41 Omar Alejandro Díaz Caballero: I think, that the axial symmetry is the starting point for left/right quarks and that leads to weak interactions, but thats is just my physical intuition of that, i may be wrong tho 03:32:52 Alberto Garcia: Thanks @Omar. I think you?re right. 03:48:25 Laxman Sharma Paudel: How about everyone post their questions on slack channel rather here? 04:11:49 Libertad Barrón Palos: Those in Mexico City, seismic alarm is ON due to an scheduled earthquake drill 04:12:50 Chi Kin Tam: where does the error come from in theoretical value? 04:46:53 Guy Leckenby: Did I read correctly that when we eat the Goldstone bosons with SSB, that produced 3 W and 3 Z massive bosons? That slide skipped by a bit fast for me. 04:49:22 Guy Leckenby: Thanks 04:50:09 Omar Alejandro Díaz Caballero: 2 W and one Z 04:58:50 Mia Kumamoto: Is it related to the vacuum quark condensate? 04:59:28 Desmond Shangase: I always thought of this as a consequence of QCD binding energy 05:02:16 Adam Szczepaniak: E (gluons) = m (proton) c^2 05:07:54 Adrian Santana: ty very much for the lectures 05:07:58 Victor Montesinos: Thank you very much 05:08:04 Angel Nava: Thanks to all the organizers and the presenters! 05:08:09 WENDY T. T. T. CHINGUWO: thank you 05:08:15 Aboona, Bassam Emad (He/Him): Thank you very much !
 
je.perez43
2021-06-22 00:34
I want to give my sincere apologies for these morning interruptions.
 
tpapenbr
2021-06-22 00:59
don?t worry about it
 
basantmagdy
2021-06-22 07:11
I want to know when the lectures Start today? How I can follow-up them?
 
sukhendu_d
2021-06-22 07:29
Can we have the pdf of presentation slides by @abhay.deshpande sir?
 
tpapenbr
2021-06-22 11:57
Today?s lecture slides
 
moywrigh
2021-06-22 12:17
Basant, I have sent you the links to the calendar/schedule and Zoom privately.
 
wsnow
2021-06-22 12:50
Abhay sorry for the \alpha confusion, I can see that I can;t keep one eye on the Zoom chat and another on the presentation and get everything right
 
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2021-06-22 13:15
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epassema
2021-06-22 13:49
Please find attached the slides of my presentation of yesterday.
 
epassema
2021-06-22 13:51
Please find attached the slides of my lecture of today.
 
albertojg12
2021-06-22 13:52
I can?t open the pdf and get an error saying the file is damaged. Not sure if it?s my computer or the file.
 
giha
2021-06-22 14:01
I receive the same error
 
mendenhallt16
2021-06-22 14:08
Same issue
 
twa73
2021-06-22 14:14
I can?t open it either. Edit: the pdf posted a few minutes earlier can be opened. Seems to be an upload issue
 
moywrigh
2021-06-22 15:36
I have asked Dr Passemar to upload again. IU Adminstrator.
 
epassema
2021-06-22 16:21
Ok very sorry I am going to upload it again.
 
ayala
2021-06-22 16:53
Identifying what the ?number of constituents N" is in a system to have an appropriate thermodynamical description is a very interesting and deep question. In general we need that this number is of order of Avogadro's number. How we reach this number in a given system depends on the interaction and the energy involved; Think of a gas in a box. If the interaction is electromagnetic, interactions are long range and the energies involved are small such that vacuum is not involved. There, the number N needs to be reached by "real molecules". In a HIC, interactions are short range and energies high enough such that vacuum is involved and can get excited. In this case, virtual particles in vacuum provide the conditions that makes us think that N is large. In fact, in the equilibrium formulation, equilibrium is reached only through the contribution of particles excited from vacuum. From this point of view, for a given energy in the collision, if these conditions are met in a HIC, then one needs a higher energy to reach these conditions in collisions of smaller systems
 
wsnow
2021-06-22 17:00
Alejandro: many thanks for this response. I think the textbooks have not yet caught up with the fact as you point out that the relevant ?N? is not necessarily the number of ?real? particles
 
ayala
2021-06-22 17:01
How we can increase the density or increasing temperature or both at the same time, experimentally to reach the critical point? The temperature and baryon density are controlled by the energy that you put in the collision. The more enregy you put in the more average kinetic energy, and thus temperature is available to the products of the collision. However, if you reduce the collision energy then you use the "stopping power" of the colliding nuclei and the n the interaction region becomes one where matter is compressed and density (and thus baryon density, since the nuclei are made out of baryons) is large. So, the upshot is that if you want large densities and still large temperatures, you reduce the energy of te collision, albeit this needs to be still relativistic (at leat a few GeV per colliding nucleon)
 
ayala
2021-06-22 17:03
how do particles act as a collective behaviour, in a statistical model? When the system hadronizes, it still consists of many hadrons that are bouncing off each other and thus transmitting energy and momentum to each other. This is the way particles equillibrate, that is, through scattering
 
ayala
2021-06-22 17:07
if you have come close to equilibrating in the dynamics, the collective thermodynamic properties determine the statistics. In this case however we are in a sense trying to go ?backwards? to use the statistics to infer if the behavior that made then was collective True, but you need to also bare in mind that the equilibrium conditions (T and mu) will be different for different collision energies. In this sense what you are trying to do is to extract those values out of the final equilibrium state.
 
ayala
2021-06-22 17:08
Is there a good way to interpret a complex value for the chemical potential? This is not possible if the chemical potential is baryon chemical potential, this is the reason why it is important to circumvent the sign problem
 
wsnow
2021-06-22 17:09
Alejandro: a historcal question. As I recall the Hagedorn temperature you discussed was already discussed in the 60s before there was direct evidence of hadron substructure. Did anyone at the time make the thermodynamic argument you gave to conclude before the experiments that there had to be hadron substructure?
 
wsnow
2021-06-22 17:11
if so: once again thermodynamics is the winner. Thermo was used to help invent quasntum mechanics by Planck and to learn about balck holes by Bekenstein/Hawking
 
ayala
2021-06-22 17:13
could you please comment on the mean pt fluctuations which is related to the heat capacity? Do you think normalized kurtosis have sensitivity to the CP at RHIC-BES energy? The mean pt is a measure of the average energy and thus of the average temperature at freeze out. Mean pt fluctuations are thus related to temperature fluctuations. The heat capacity of a substance is the amount of "heat" that you need to make the substance to raise its temperature so there is a strong connection between these fluctuations and the heat capacity.
 
ayala
2021-06-22 17:15
Yes, in fact in Hagedorn's original note this is conjectured
 
wsnow
2021-06-22 17:24
thx for info
 
chun-jian.zhang
2021-06-22 19:56
thank you. and do you think the normalized kurtosis has sensitivity to the CP at RHIC-BES energy?
 
davoudi
2021-06-22 21:23
Strong Interactions on the Lattice I
 
tpapenbr
2021-06-22 22:38
Tomorrow?s lecture slides
 
mashephe
2021-06-23 12:12
Here's a copy of my slides for later this morning.
 
erica_cardozo
2021-06-23 15:03
has joined #nnpss
 
ayala
2021-06-23 16:51
what are restrictions when we select a specific centrality class ? and the range of pesuorapidity ? how multiplicity changes according the type of collision ? In practice, the centrality class that a given collision belongs to requires estimating the number of participants and spectators. The last can be estimated for instance using the forward detectors. Once this is done then one uses a Glauber model to assign to it a dentrality class according the the translation plot shown in pp 101 of the lectures. The range of pseudorapidity is selected by appling cuts to the tracks. If the particle is ultrarelativistic these cuts are simply geometrical in other words one considers only tracks within a ginven angular cone around the transverse direction. If the particle is not ultrarelativistic one can always use the energy (for identified particles) and pz to find the pseudorapidity and use only the selected range of pseudorapidity to make the cuts. If RAA shows a only momentum shift (not actually fewer particles formed), should?t the RAA ratio go to one if integrated over the entire pT spectrum? Yes, provided that you count all of the particles in the away side within a cone which is larger than the cone in the leading side. However, for the R_AA analysis you keep both cones (leading and away sides) of the same size to emphasize that within such cone the away side particle lost energy that was then redistributed in soft modes and thus carachterizes the interaction with the bulk particles.
 
bem4r
2021-06-23 17:21
Would it be possible to post the slides from @abhay.deshpande?
 
abhay.deshpande
2021-06-23 17:31
Sorry folks, forgot to upload my slides from yesterday. I am uploading both slides now:
 
abhay.deshpande
2021-06-23 17:34
Bassam Aboona, can you or some one else confirm you now see my slides from lectures 1 and 2?
 
je.perez43
2021-06-23 17:38
I can see your slides. Thank you!
 
rajeev.singh
2021-06-23 17:39
Yes Sir, I can see.
 
moywrigh
2021-06-23 17:41
Yes, we can see them. Thank you!
 
bem4r
2021-06-23 17:43
@abhay.deshpande Thank you very much! Yes, I am able to see them.
 
andi.mankolli
2021-06-23 21:44
Thank you. That's a very intuitive explanation!
 
maianh
2021-06-24 14:04
Dear Prof. @Maria Jose Garcia Borge. Thank you so much for coming through this school. I am extremely grateful and greatly appreciate the presentation you gave. Cannot wait to see you tomorrow with in-flight method and some experiments using RIBs. Could you please share your slides with us?
 
davoudi
2021-06-24 15:14
Slides for today?s lecture (including those of last time).
 
abhay.deshpande
2021-06-24 15:35
Folks, here is the EIC lecture 3. . If there are questions, I am happy to answer them here. Good luck and my best wishes to all of you.
 
mashephe
2021-06-24 15:53
Slides for today's lecture:
 
giha
2021-06-24 18:08
General question for all speakers: for many of us grad students, our advisor?s expertise constrains the general subject of our day-to-day research. For example, one can?t exactly write a thesis on relativistic heavy ion collisions if one?s advisor has funding for low energy nuclear physics or vice versa. If we want to get involved in your subfield post-graduation, what?s the best way to prepare? What are some necessary skills that are unique to your subfield, and what are your favorite resources for learning?
 
tpapenbr
2021-06-24 20:56
what?s the best way to prepare: (For low-energy nuclear theory) Good working knowledge of QM including second quantization; numerical skills;
 
tpapenbr
2021-06-24 20:56
what are your favorite resources for learning? Not-too-large-sized research problems that lead to a publication in a few months
 
davoudi
2021-06-25 00:48
@giha and all, in the US funding system, a full-time graduate student is not paid more than 20hr/week even if the student is working on their thesis and done with their courses. So technically, and what I always remind my students, they can and they should spend at least half of their time learning new things, whether it is directly related to their ongoing paid research or not. Once you graduate, you will be paid to do a specific things full-time, so it is your chance as a grad student to get yourself as educated as possible so to develop useful tools and understandings of different subject areas. So if you decide to do something different as a post-doc, you will not have a hard time switching between fields. After all, that?s why you are in this summer school. One of the ways to learn (best way!) is to do a research project, so don?t be shy to start new collaborations and expand beyond you mainstream work. I can give you hundred examples of how this worked out extremely well for many students I know. Keep in mind though: openness and honestly with you advisor is a key. You do not want to compromise your thesis work or your relationship with your advisor by embarking on a work that he/she doesn?t approve or is not informed of. Always update your advisor and keep expressing your appreciation for their wisdom and vision. After all the majority of physicists are reasonable and supportive and if you convince them that you are doing something useful with your time and you have good reasons for branching out, they would totally understand.
 
davoudi
2021-06-25 00:57
Now ? how you reach out to other faculty, particularly outside your own institution (assuming advisor approves), to get them trust you and give you a project. You should keep in mind that faculty are oversubscribed, overcommitted, and extremely busy. Even managing their own group can be twice a full-time job, why should they supervise you. Here connections matter. If your advisor can be your reference and assure a colleague that you are motivated and can be useful, that helps. If you have attended a summer school and have shown interest and strength in the subject material, for example have shown dedication in solving exercises and contributed to discussions, it can have good impression on instructors and give them a reason to talk to you afterwards. If such connections do not work out or cannot be built, there are systematic ways to take advantage of multi-institutional programs. For example, US Department of Energy has Graduate Research Fellowship programs which pays students over summer to spend time at a national lab of their choice and work with the PIs there. You should keep an eye for such opportunities in your country and go for them if you are eligible.
 
moywrigh
2021-06-25 10:51
Dr Borge is sharing a paper she recently wrote about RIB facilities
 
aszczepa
2021-06-25 12:08
1. Read, read, and ?. read. Now that all ?classic? papers are online you don?t even have to spend nights in the library. 2. Reach out to researchers who work on topics that you may be interested in (again its much easier these days with the online tools) 3. Get involved in various projects
 
mashephe
2021-06-25 12:36
Regarding exploring new things... for those wanting to explore data analysis, try this: https://particle-physics-playground.github.io
 
aszczepa
2021-06-25 14:24
Hi Thomas can you point me most recent reviews and maybe code repo for coupled cluster calculations
 
davoudi
2021-06-25 14:37
The slides for today?s lecture (including those of the past two lectures):
 
giha
2021-06-25 14:40
@davoudi Thanks for such comprehensive advice! I guess there?s no better way to learn than to get involved in whatever capacity we can.
 
giha
2021-06-25 16:01
@aszczepa Thank you as well! I agree the internet makes acquiring background knowledge that much easier.
 
tho14
2021-06-25 16:08
Hello everyone, and thanks to all the speakers for the highly informative talks. Here is the general question I had for the speakers at the end of the school: What is the best option for students currently in the Physics PhD. program to navigate the PhD. to faculty pipeline? Is it in one?s best interest to only get a postdoc position following the PhD instead of getting into the industry for a different kind of experience before returning to academia? Thank you!
 
arnava
2021-06-25 17:14
Hi Zohreh thanks again for your talks, I wanted to ask a question that I felt was too tangential for your talks, I have a naive understanding of axions but I do know they have been proposed as dark matter candidates and that they can arise from QCD. Is there a way to describe these using lattice QCD?
 
sdawid
2021-06-26 18:13
Dear @tho14 and All, I am not sure how helpful this could be, but in 2016 there was a special issue of Nature discussing some realities of the young researchers' lives. It can be found here https://www.nature.com/collections/bfgpmvrtjy.
 
 
tho14
2021-06-26 20:44
Hi @sdawid, thanks for sharing these links. They are really great reads and I found them very insightful!
 
tpapenbr
2021-06-28 12:51
 
tpapenbr
2021-06-28 12:53
 
tpapenbr
2021-06-28 13:01
Those codes are mainly for education purposes; the one we use runs on computers at ORNL
 
jforson
2021-06-28 16:25
Hello. I was wondering if someone had the nuclear astrophysics slides from Friday?