PASI 2012: rotten tomatoes?

The discussion began with a complaint about a theory slide from yesterday's talks: an equation with 24 terms? why on earth put it there and dedicate 6 seconds to explain it? Are our standards for presentations so achanchados that we tolerate such persistent background of bad talks? How much do we value properly communicating our good science at a conference?

We were just a sample of the young scientists in the conference happily chatting over some half finished dishes of camarao. We let our imagination fly and set to change the world, and the PASI 201X slowly took shape.

The first idea was to have a second projector showing live tweeter comments from the audience. I liked it even if I despise tweeter. Of course, a big loud buzz going off when time is over is essential, just to show the speaker who is in charge. And what if we give 'clickers' to the audience and poll them as the talk goes on? A trap door in the stage would open when the approval rating reaches the level of Italian politicians, sending a surprised speaker into a swimming pool. Maybe we should just give the audience control of advancing the slides. They could decide to halt the presentation in those absurdly complicated slides until the speaker has gone through the torture of explaining every detail. Clickers and technology are out there, power to the people!

Shall we replace session chairs, and their fluctuating skills, with a panel of multidisciplinary experts with the authoritative and intimidatory powers of a thesis defense committee, or of supreme court judges? They would be able to exert enough force to keep even the most reputable figures of our community on track, and discussing topics interesting to the bulk of the audience.

The draft of the plan, which might or might not involve some sort of "last physicist standing" element, is now on the hands of Meredith. I can not reveal more details so as not to interfere with the grant writing process, but we only have to finalize a few things here and there. For example, do we apply to the NSF, or to the Discovery Channel? They need a show to replace the aging MythBusters!

PS: today Ed Brown showed us the way speakers can strike back: Quizes.

Talk-delayed blog post emission

My apologies to Valdir Guimaraes for this late post, but I was busy selfishly tending to my own interests. Valdir told us about Light Radioactive Nuclei Capture Reactions By Phenomenological Potential models. The point of this talk was to demonstrate the importance of knowing capture cross-sections on light nuclei and show us how he can use a potential model based indirect data as well as direct data on neighbouring nuclei to make predictions for these cross-sections.

The light nuclei Valdir is referring to give us insight on light halo nuclei (e.g. 11Li and 11Be) as well as the A=8 gap present in cosmic abundances (e.g. 8Li 8B). Capture cross sections on light nuclei can effect early r-process nucleosynthesis, the pp-chain in the sun, as well as yields for big bang nucleosynthesis. Unfortunately I have to disagree with a point made by Valdir on the motivation for BBN. He said that observed abundances of 4He, 3He, 2H, and 7Li disagree with experimental capture cross sections, but this is actually only true for 7Li. Initially it was thought that all disagreed, but more careful approaches to observation have proved only 7Li disagrees with current nuclear knowledge (see R. Cyburt's lecture on BBN at http://www.nscl.msu.edu/~cyburt).

Ingredients in Valdir's potential model are the spectroscopic factor, the bound state potential, and the scattering potential. Each of these pieces of information are extracted from various pieces of experimental data, e.g. the spectroscopic factor can be obtained from data on transfer reactions. Valdir showed us a few examples of how his potential model accurately reproduced known capture cross-section data and it seems his model does quite a good job. However, maybe I missed them but I didn't see any predictions for less well known cross sections or the impact of these predictions. Without any interesting predictions, the potential model certainly loses the sexy-factor that comes with predictive power.

Brad's FRIB

Longest. Blog. Ever!

Asked what he thought of being blogged/taped as he prepared- Bad Bad Brad Sherrill said he was more concerned about bloggers harping on mistakes or jokes in the talk. How prescient. The live audience seems to be more of a threat than the bloggers, though. I wonder which jokes didn’t make the cut.

Here’s his plan: lay out the beam production mechanisms, discuss some fundamental symmetries you can test with those beams, and then round out the 45 minutes with societal applications and benefits from rare isotope facilities. This is not 100% FRIB, as I thought, but more a picture of where FRIB fits in the (modern) RIB facilities.
This is ambitious and a nice complement for a program that is riddled with a good number of speakers who haven’t fully embraced the spirit of reaching beyond our own special little corner in science.

15.05 Baha points out Brad’s tongue slip of identifying the protons as neutrons.
15.08 9 is less than 8. Ernst finds the new nucleus: Z=7 flourine. Congratulations, Ernst. But you don’t get to name it. Ernstinated toothpaste just sounds weird.
15.11 List of production mechanisms. Promises resources for the wiki. I must recruit him. Cha-ching for the Rare Isotope Facilities working group! The trick is to get all these promises made during the talks to be realized in the next week before people stop working on it.
15.12 List of good mechanisms for producing nuclei close to stability. (p,n), (p,nn) Also, fusion evaporation has large cross section. Good to know.
15.13 Fusion-fission!! 238U+12C fizzes to heavier isotopes—laser acceleration in the future. Good for getting nuclear physics on the movie screen. Lasers are camera friendly. How does one get the job of being a consultant for Hollywood?? That is never covered in physics career services….
15.15 Brad is doing the math in his head for 3He(58Ni,60Zn)n real quick. It quickly washes over his face that (58Ni,60Zn)n is ok. I enjoyed some of the finer details of production concerns for different types of nuclei. Having spent so much time at the NSCL, I have had a hard time wrapping my head around what happens at other types of facilities.
15.18 On to higher energy production mechanisms.
15.20 Spallation (wiki commons file shown) Ooo- video! It is just like fragmentation, except you get the beam nucleus from the target instead of the primary beam.
15.22 Shows range of isotopes you get for given processes. Nice to see what you will get at what facilities without having to look up a table. It is not quite second nature to me yet. But soon we will have the wiki. Hendrik will see to that.
15. 25 Explains abrasion and oblation terms and fills in details of fragmentation process. I hate abrasion/oblation talks and all their terminology. Brad confirms my suspicion that those talks employ unnecessary mystery about what they are doing.
15.28 He is behind schedule. I am worried he won’t get through all three sections. He is still in the first! One too many production curves, Brad.
15.29 Q_g term name- historical, and now I want to know the story. Probably a let down. Q_g is binding energy between beam and fragment (ME(beam) – ME(frag)). Production cross sections tell you about how well mass models are doing. Ah. That excited a few people in the room.
15.32 He’s screwed. No way he has enough time. I’ve never seen this before from Brad.
15.35 In 1966, 1000 know isotopes. Now, around 3000.
15.38 He’s referencing my jargon page. Must steal his pictures for jaron page in the name of my (non)working group page.
15.39 Reminds us the efficiencies are an important factor in getting a good intensity beam. True dat.
15.43 Good map. Going to steal that, too. This talk is more reconnaissance for me….
15.45 Holy crap—2E13 particles from U fission!!!
15.46 LISE++ advertisement.
15.49 Rap- You can thank Zach Meisel. YouTube making its entrance into the physics conference world. Fun at Brad’s expense. Good sport.
15.50 Still sorry he didn’t get to symmetries and societal impact as promised. Turns out- Brad is a tease.

Overtime: So when do you think FRIB will see first light? Brad: 2018. I’ll be starting a pool on how far behind schedule they ultimately go. Cash only.

15.54 Dying to AutoTune Brad Sherrill’s talk. Any suggestions on the music? Would be better if there were video of Brad talking.

15.55 Questions- finally. Discussion includes high vs. low energy experiment, the 6-12 months dead time between the NSCL turning off and FRIB turning on; a new hire Oscar at the NSCL to look at correlations in Beta decay for new physics in the weak interactions; doing EDM measurements an order of magnitude beyond TRIUMF. Baha wants the latter in writing: Done.

Simulation of Silicon Detector Response

It was increadible how Zach looked like very calm during his presentation. He had changed a little the title of his talk, but he could show the results of the simulations using GEANT4 for the response of a DSSD detector comparing with experimental data. And he did propaganda of Marcelo's talk on Thursday. I don1t knowif Marcelo was expecting it. : )

6He+9Be reaction

This was one of the student seminars and Kelly did a very good presentation. In the beginning she was a little nervous, like all the students when present their work in a different language and in front of too many professors. In her place, I would stay in a panic.

She talked about the study of 6He+9Be reaction, the experimental results obtained in Brazil and the theoretical predictions were made in colaboration with people from Seville, Spain.

The Drinks of Brazil - Caipirinha

The Caipirinha is the national drink of Brazil. I have collected accounts of the Caipirinha being a good 'any time' drink to have in the morning, afternoon or night; However, if you drink too many in the morning you will be out like it's night. According to the International Bartenders Association it is made with 2 teaspoons of sugar 1/2 a lime and 5 cl of cachaça, although I doubt most bartenders measure that exactly. The Caipifruta replaces lime with some other fruit and sometimes adds condensed milk.

Break up in Buenos Aires

Alberto Pacheco presented what I found was the most clear description of break up reactions so far. Perhaps it was that I was blogging the talk and payed 'extra attention'. Perhaps it was that he restricted the explanations of break up to the bare essentials - referring to the talks from last week for additional information. It worked for me.

We learned how break up is a reaction when something breakups. We detect the pieces flying out, and from there we'd like to understand what happened. It's not so simple as it sounds. Experimentalists collect information on energy and momentum of the reaction products, in a limited set of detectors. This must be used to reconstruct how the reaction proceed (with SUPERKINETICO code), and understand which of the many alternative processes we group in the breakup bag took place. Understanding breakup is an advancement of science in itself, but it also contributes to fields such as astrophysics (better understanding of capture reactions through Coulomb dissociation), and reaction theory (to enhance or reduce fission by breakup? such is the question).

He showed results for 6Li+144Sm, and 7Li+144Sm, but I missed what the results had to say about the aforementioned questions. It would also had been nice to have some words about the Tandar lab, which I think was for the first time a main character in the plot.