In particle physics, we often use toy models, both to describe complicated things in (hopefully) easier to understand ways, but also to quickly study the effects of some changes to a detector or to some analysis. Now, students of the University of Tokyo gave us a whole new toy to look at: A full model of the Belle-II detector… constructed in LEGO. Complete with illuminated particle tracks, it gives us all something to look at while we are working to construct the real thing.
Archive for January, 2011
« Des valeurs partagées pour une nouvelle réalité. » Tel sera le thème de la réunion annuelle du Forum économique mondial qui se tiendra cette semaine à Davos ; un thème qui interroge particulièrement la science. Notre discipline repose en effet, et depuis toujours, sur une communauté de valeurs : si les laboratoires de physique des particules du monde entier ne mettaient pas en commun ouvertement et librement leur savoir-faire, notre compréhension de l’Univers au niveau fondamental aurait stagné depuis des années. Et si la recherche fondamentale et la recherche appliquée n’étaient pas en constante interaction dans nos laboratoires, les technologies issues de notre discipline seraient encore dans les limbes. Je me rendrai à Davos cette semaine, et c’est ce message-là que je m’efforcerai de transmettre.
Que le CERN soit invité au forum de Davos cette année est un signe très encourageant pour la science fondamentale. Cela témoigne d’une reconnaissance de la part des membres du Forum de l’importance de la science fondamentale pour la société, et aussi du rôle pilote que joue la physique des particules dans la mondialisation scientifique. Beaucoup voient la mondialisation comme une menace ; pourtant, notre science démontre à quel point elle peut être bénéfique à tous.
Dans notre discipline, les valeurs partagées, à travers le monde, est la règle depuis bien longtemps. La collaboration internationale est dans nos gènes. Aujourd’hui, l’ouverture du CERN à des pays non européens renforce encore cette tendance. Cette année commencera le processus de redéfinition de la stratégie européenne pour la physique des particules, publiée initialement en 2006. Parallèlement, la communauté mondiale de la physique des particules fondamentales travaille sur une vision d’ensemble de la discipline. Tout cela montre que la physique des particules au niveau mondial avance de manière coordonnée, ce qui permet d’optimiser les investissements des organismes de financement afin de diffuser la connaissance et l’innovation au profit de tous.
Cette optimisation ne se limite pas à la collaboration au-delà des frontières, mais concerne également l’enrichissement mutuel de la science fondamentale et de la science appliquée. Le CERN, qui est connu pour sa science fondamentale, a également beaucoup à apporter dans différents domaines de la recherche appliquée. Il suffit de penser au World Wide Web, ou à de nombreuses avancées dans le domaine médical, qui ont vu le jour dans des laboratoires de physique des particules tels que le CERN. L’essentiel est d’assurer la circulation du savoir entre science fondamentale et science appliquée, pour que les nouveaux concepts inspirent les innovateurs, et que les nouvelles technologies inspirent les chercheurs. Par ailleurs, il est capital que des installations aussi médiatisées que le LHC, qui sont de véritables sources d’inspiration, continuent de prospérer. Ce sont des projets de cette envergure qui attirent les jeunes cerveaux vers la science, qui favorisent le dialogue entre science et société, et qui font prendre conscience du rôle essentiel de la science dans la vie de chacun.
Les valeurs partagées sont une évidence dans le monde de la physique des particules ; c’est un message fort que nous enverrons à tous les dirigeants du monde réunis à Davos. Il est beaucoup question, lors de ces rencontres, de l’« esprit de Davos » ; la manifestation n’est pas simplement un moyen de créer un réseau pour les dirigeants, mais aussi une occasion pour les participants de rencontrer des interlocuteurs inhabituels, qui parfois remettent en question leurs modes de pensée et d’action. Je souhaite rentrer pleinement dans cet esprit. Je souhaite renforcer l’idée que dans notre discipline, la science, la mondialisation joue un rôle positif ; je voudrais aussi contester l’idée que nous devons choisir entre recherche fondamentale et recherche appliquée. Nous n’avons pas à choisir. Et ce constat est d’autant plus vrai en un temps de ralentissement économique, alors que la science fondamentale se veut plus importante que jamais.
Rolf Heuer
Want to “play” with subatomic particles? You could work at Brookhaven Lab’s Relativistic Heavy Ion Collider (RHIC) or the LHC — or you could play a new card game invented by a group of Hungarian students and RHIC/PHENIX collaborator Tamás Csörgő.
The students — Csaba Török and his friend Judit Csörgő (Tamás’ daughter) — invented the game as an entertaining way to learn about subatomic particles and their interactions, inspired by physics presentations in the science club at their secondary school, where Tamás was a frequent presenter.
The game, now available for purchase in both Hungarian and English, “provides a great opportunity for all people — not just physicists — to get acquainted with some of the elementary particles and concepts of the Standard Model,” said Csaba.
The deck consists of cards that represent particles and anti-particles from neutrinos, to electrons, positrons, muons, and quarks, which can be used for four different games. In “Quark Matter,” a game that models RHIC physics, the cards are mixed face up on a table, packed closely together to represent matter at the instant of collision — a quark-gluon plasma (QGP). The object for each player is to quickly extract particles as they would emerge from the collision, in order: non-interacting neutrinos and antineutrinos first, followed by electron/positron and muon/anti-muon pairs, and then quarks and anti-quarks as they hadronize, or freeze out, to form mesons, baryons, and anti-baryons — all while maintaining a neutral color charge.

Brookhaven's Educational Programs staff introduced the card game to students at Rocky Point Middle School.
As players race to extract cards, the “system” expands just as it does in a real RHIC collision. Players score points for each correct particle pick. More sophisticated players can name the particles as they extract them. Additional games teach and reinforce deeper concepts, such as weak decays and several laws of conservation.
For more information, visit particles card game.
-Karen McNulty Walsh, BNL Media & Communications
Years of Fermilab computing work build base for stunning SDSS image

Top left image shows SDSS-III's view of a small part of the sky, centered on the galaxy Messier 33. The middle top picture is a zoomed-in image on M33, showing the spiral arms of this galaxy, including the blue knots of intense star formation. The top right-hand image shows a further zoomed-in image of M33 highlighting one of the largest areas of intense star formation in that galaxy. Credit: SDSS
The world’s largest, digital, color image of the night sky became public this month. It provides a stunning image and research fodder for scientists and science enthusiasts, thanks to the Sloan Digital Sky Survey, which has a long connection to Fermilab.
Oh, yeah, and the image is free.
The image, which would require 500,000 high-definition TVs to view in its full resolution, is comprised of data collected since the start of the survey in 1998.
“This image provides opportunities for many new scientific discoveries in the years to come,” said Bob Nichol, SDSS-III scientific spokesperson and professor at University of Portsmouth.
Fermilab oversaw all image processing and distribution of data to researchers and the public from 1998 through 2008, for the first seven batches of data. These batches make up a large chunk of the ground-breaking more than a trillion-pixel image. The eighth batch of raw, reduced data, which was released along with the image at the 17th annual meeting of the American Astronomical Society in Seattle was processed by Lawrence Berkley National Laboratory. LBNL, New York University and Johns Hopkins University distributed that data. Fermilab’s SDSS collaboration members now focus solely on analysis.
“This is one of the biggest bounties in the history of science,” said Mike Blanton, professor from New York University and leader of the data archive work in SDSS-III, the third phase of SDSS. “This data will be a legacy for the ages, as previous ambitious sky surveys like the Palomar Sky Survey of the 1950s are still being used today. We expect the SDSS data to have that sort of shelf life.”
The release expands the sky coverage of SDSS to include a sizable view of the south galactic pole. Previously, SDSS only imaged small, spread out slivers of the southern sky. Increasing coverage of the southern sky will aid the Dark Energy Survey and the Large Synoptic Survey Telescope both southern sky surveys that Fermilab participates in.
Comparing the two portions of the sky also will help astrophysicists pinpoint any asymmetries in the type or number of large structures, such as galaxies. Cosmic-scale solutions to Albert Einstein’s equations of general
relativity assume that the universe is spherically symmetric, meaning that on a large enough scale, the universe would look the same in every direction.
Finding asymmetry would mean the current understanding of the universe is wrong and turn the study of cosmology on its head, much as the discovery of particles not included in the Standard Model would do for collider physics.
“We would have to rethink our understanding of cosmology,” said Brian Yanny, Fermilab’s lead scientists on SDSS-III. So far the universe seems symmetric.
Whether the SDSS data reveals asymmetry or not it undoubtedly will continue to provide valuable insight into our universe and fascinate amateur astronomers and researchers.
Every year since the start of the survey, at least one paper about the SDSS has made it in the list of the top 10 astronomy papers of the year. More than 200,000 people have classified galaxies from their home computers using SDSS data and projects including Galaxy Zoo and Galaxy Zoo 2.
In the three months leading up to the image’s release a record number of queries, akin to click counts on a Web page, occurred on the seventh batch of data. During that time, 90 terabytes of pictures and sky catalogues were down loaded by scientists and the public. That equates to about 150,000 one-hour long CDs.
Scientists will continue to use the old data and produce papers from it for years to come. Early data also works as a check on the new data to make sure camera or processing flaws didn’t produce data anomalies.
“We still see, for instance, data release six gets considerable hits and papers still come out on that in 100s per year,” Yanny said.
So far, SDSS data has been used to discover nearly half a billion astronomical objects, including asteroids, stars, galaxies and distant quasars. This new eighth batch of data promises even more discoveries.
Fermilab passed the job of data processing and distribution on to others in 2008. The eight batch of data was processed by Lawrence Berkley National Laboratory and distributed by LBNL, New York University and Johns Hopkins University.
Fermilab’s four remaining SDSS collaboration members now focuses solely

illustration of the concept of baryon acoustic oscillations, which are imprinted in the early universe and can still be seen today in galaxy surveys like BOSS. Credit: Chris Blake and Sam Moorfield and SDSS.
on analysis. They are expected to produce a couple dozen papers during the next few years. The group touches on all of SDSS-III’s four sky surveys but focus mainly on the Baryon Oscillation Spectroscopic Survey, or BOSS, which will map the 3-D distribution of 1.5 million luminous red galaxies.
“BOSS is closest to our scientists’ interests because its science goals are to understand dark energy and dark matter and the evolution of the universe,” Yanny said.
For more information see the following:
* Larger images of the SDSS maps in the northern and southern galactic hemispheres are available here and here.
*Sloan’s YouTube channel provides a 3-D visualization of the universe.
*Technical journal papers describing DR8
and the SDSS-III project can be found on the arXiv e-Print server.
*EarthSky has a good explanation of what the colors in the images represent and how SDSS part of an on-going tradition of sky surveys.
*The Guardian newspaper has a nice article explaining all the detail that can be seen in the image.
— Tona Kunz
Hi, folks!
I’ve been absent for a while on account of switching jobs: from “graduate student/research assistant” to “plot-slash-table-making automaton.” The cynical among you may argue that these are essentially the same thing, but it helps me sleep at night to believe otherwise. Well. At any rate, I’ve had several blog post ideas sloshing around in my head for months now, and rather than age to perfection, they’ve gotten all… mushy. Here is your first serving of mushed thought.
I went home to Michigan for Christmas. Things were pretty much the same, modulo the effects of prolonged regional economic distress and the strange sensation that everything and everyone was larger than they should be (cars, portion sizes, distances to points of interest, family members). Naturally people wanted to know what I’d been up to, but I was mostly at a loss for words: How does one condense high-energy physics and la vie CERNoise into a quip or anecdote that connects with non-physicists?
“I work a lot.”
Surprisingly, that seemed to satisfy most questioners. Also: “Haven’t managed to destroy the world yet.” For more thorough and eloquent answers, I turned to CERN’s visitor center and gift shop, bringing home a few CERN/physics books as both gifts and conversational references. When a friend asked about “the Higgs Bassoon,” I pointed her to a fully illustrated children’s book showing the basics of the Standard Model and how physicists are able to study it. “No, it’s not a woodwind instrument, it’s a hypothetical fundamental scalar boson.” This was the same book I gifted to my mom; tomorrow, on her 50th birthday, I will be sending her a quiz to assess what she learned. I am a terrible son. My dad had mentioned to me a drinking buddy who fancied himself a physics enthusiast, so I gave my dad a more advanced but still brief introduction to particle physics in order to impress this guy and, one hopes, get a free drink or two out of the exchange. See? My field has practical applications. In related news, my grandma found the Higgs Boson.
The whole experience has underscored the importance of accurate, accessible communication between scientists and the general public. This US LHC blog is a nice venue for such conversations, right? 🙂 But as for a much wider scale, let me just say that I’m incredibly thankful for all the science journalists and other folks out there engaged in outreach (Daisy, Bryan, Katie, …). We all benefit from your excellent metaphors.
I went home to New York for New Years. I was surprised to find that people in bars really like hearing about the LHC; I was not surprised to hear some call it the “Large Hardon Collider.” Emergency physics lessons ensued.
It’s easy to forget about (or at least willfully ignore) my institution, Stony Brook University, when it’s so far away, but since I was in the neighborhood, I swung by to say hello to my advisor and physics friends who don’t work at CERN. This was a dangerous move: advisors are pretty much obligated to request plots and tables from their advisees, and I quickly reverted to the automaton existence I’d left behind. Sigh. Absence really does make the heart grow fonder — will keep in mind next time I consider visiting.
Oh, one more thing before I get back to making last-minute plots for the ATLAS note I and my colleagues have been working on for some time (and will soon be submitting!) : Let’s please have a moment of silence for the Tevatron, a pioneer and workhorse in high-energy physics for the past two decades, whose funding won’t be extended beyond 2011.
It’s time for the LHC to really, really shine.
— Burton
娘が生まれて四週間になる。生活環境が激変したことで研究アクティビティを落としたら、それこそ最も自分が自分を嫌いになるので、分担育児を研究の技術にすり替える技術を着々と習得している。
思えば7年前に上の子が生まれた時は、全て妻に任せっぱなし。自分は研究をがんがんやればそれでいいと思っていた。子供が生まれたことは仕事に打ち込むための動機の一つ、という捉え方だった。その頃の日記を見てみると、まさにそう書いてある。しかし今回はかなり違う。家庭の環境がその頃から変わっているということもあるし、研究環境も駒場から理研に移って変わったということもあるが、真の理由はそれではない。むしろ、demandingな環境をいかにさばき能率を上げることが出来るか、を楽しめるようになったという感じだ。
育児はかけがえの無い時間だ。小さな小さな人間としての娘、自分では何も出来ない娘を腕に抱えていると、この時間は他の何物にも代え難いという事実が頭を占領する。一方で、自分にはやりたい仕事があり、家族でやり遂げたい夢もある。で、自分の時間が限られているからどれかをあきらめよう、という考え方は決してしたくない。どれもやる。そのためにはどうすればいいか。そう考える。
誰かがtwitterで言っていた、「育児と仕事を同時にすることは、育児をあきらめることなのです」と。それはある意味正しい。しかし育児には完璧はない。こちらも学んで行くのだ。仕事にも完璧はない。仕事をしながら学んで行くのだ。従って、あきらめるという観点自体を持ち込むことは、疲れた自分をいやす程度の目的でしかない、と理解しておくことは重要だ。健康が第一なので、疲れていると休まないといけない。それはあきらめだろうか。いや、次のステップへの準備なのだ。
夜3時間置きに起きる娘との時間を、幸福に感じることができる今は、成功していると言える。もちろん、妻が献身的に育児をしているから、分担と言っても自身の担当の時間は少なく、それがストレスをかなり軽減しているのは明らかだ。しかし明らかに7年前とは違う自分がいることを認識している。夜起きる必要があるのなら、日本の夜が昼になっているヨーロッパの共同研究者と議論すれば良いではないか。
いろいろな人の助けで、研究室も大変円滑に動いている。研究室発の論文にはRIKEN-MP-#という番号をつけている。研究室が始まって9ヶ月、この番号も13になった。毎週の研究室ミーティングから始まり、議論とセミナーが続々と続く。4月からのセミナーの数も30に近くなっている。まさに、研究室メンバーの努力と、研究室を支えてくださる方々のおかげである。
日本科技大教授上田次郎の言葉が好きだ。「なぜベストを尽くさないのか」
Shared norms for the new reality. That’s the theme of the World Economic Forum’s annual meeting in Davos next week, and it’s a subject that resonates well with science. Shared norms underpin the success of our field and always have: if the world’s particle physics labs did not share their know-how freely and openly, our understanding of the universe at the fundamental level would be decades behind. And if basic and applied research did not constantly interact at our labs, the technologies our field has spawned would still be waiting in the wings. I’ll be going to Davos next week, and this is the message I’ll be taking with me.
The fact that CERN has been invited to speak at Davos this year is a very positive sign for basic science. It shows that the members of the Davos club recognise the value of basic science to society, and it also recognises the leading role that particle physics plays in scientific globalization. To many, globalization is seen as a threat, but our science shows how it can work to the benefit of all.
In our field, sharing norms around the world has been a reality for decades. Cross border collaboration is in our genes. Today, with CERN opening up to countries from beyond Europe, it is becoming more firmly established than ever. This year, Europe begins the process of reviewing its strategy for particle physics, first published in 2006. And in parallel, the global particle physics community is working towards a global vision for the field. Together, these initiatives show that particle physics around the world is planned and executed in a coordinated way. They ensure that funding agencies can be confident that their investments in particle physics are optimised to deliver knowledge and innovation for the benefit of all.
Such optimisation does not just apply to cross border collaboration, but also to the cross fertilisation of basic and applied science. CERN is known as a basic science lab, but we have much to contribute in applied areas of research as well. Just think of the World Wide Web, or numerous advances in the medical arena that began their lives in particle physics labs like CERN. What’s essential is to ensure that knowledge flows between basic and applied science, so that new ideas are there for the innovators, and that new technologies are there for the basic scientists. It’s essential too that highly visible facilities like the LHC, which have the power to inspire, continue to thrive. It’s projects like these that attract bright young minds to science as a whole, that serve as a vehicle for greater dialogue between science and society, and that can foster appreciation of the vital role science plays in all of our lives.
The fact that sharing norms comes so naturally to particle physics is a strong message to the world leaders who will come together next week in Davos. The World Economic Forum makes much of the ‘spirit of Davos’, saying that the meeting is not simply a network for leaders, but rather an opportunity for participants to connect with people they don’t know, people who challenge the way they think and act. My aim is to enter fully into the spirit of Davos. To reinforce the message that in our field of science, globalization is a force for the good, while challenging the notion that we have a choice between basic and applied research. We do not. And that’s particularly true at a time of economic downturn, when basic science is more important than ever.
Rolf Heuer
A New Year: Heavy Ions, Dark Matter, and back to a Life on the Road
It is the middle of January, and the new year is definitely keeping me busy. Lectures are still on at the Technical University of Munich, and a good week ago, I kicked of the year for my students with a journey back in time for me: Heavy Ion Physics, and the search for / study of the Quark Gluon Plasma, or what is now called a strongly coupled QGP aka The Perfect Liquid. For my PhD thesis finished six years ago, I worked at the STAR experiment at Brookhaven’s Relativistic Heavy Ion Collider RHIC, a facility we’ll be hearing of here quite a bit in the future in BNL’s blog, I’m sure. Back in my time as a student at RHIC, the results that led to the discovery of the sQGP, such as the observation of collective flow of the matter produced in the collisions, evidence for the absorption of jets in the hot and dense medium (“Jet Quenching”), … were just coming together, truely an exciting time. Today, things are equally exiting in this field: We are now seeing first results from Lead-Lead collisions at the LHC, which show a fantastic strength of the jet quenching, spectacularly illustrated by event displays from the experiments, and a continuation of the almost ideal hydrodynamic behavior of the matter it this new, much higher energy. The very first impressions were nicely summarized in a Physics Viewpoint.
I’ve been giving my lecture on high energy hadron collider physics for the third Winter in a row, but this time is really special: All topics that I cover now have new LHC results to go along… Detector physics, Top Quarks, seaches for exotic phenomena like micro black holes, heavy ion physics… and SUSY will be coming up next on my list. I hope I can convey some of this excitement to my students!
Then, two days ago I took a quick detour to Dark Matter physics, since I had Laura Baudis from Zurich as a guest in the Munich physics colloquium. Another area with a lot of excitement currently: Direct detection experiments could see really convincing signals from dark matter particles any time now, and there is already quite some controversy about exiting results. Definitely something to watch out for in the near future!
And, after a couple of weeks in Munich, I’m back to my life on the road: Two days in Hamburg, already completely filled with discussions about publication plans and analysis results from the CALICE calorimeters… And the trip gives me the opportunity to blog from where I usually do: At the airport, waiting to board…
Given that today is Martin Luther King Day it seems like a good time to reflect on the under-representation of African Americans in physics. This is a chart showing the number of African Americans who earned PhDs in physics in the US:
African Americans earn approximately 2% of PhDs in physics earned by US citizens in the US. You can find more statistics on African Americans in physics here. African Americans are about 12% of the US population. Clearly something is wrong here.
I am not the right person to talk about what it is like to be a black physicist. I can’t tell you what it feels like because I’m white. Even though I’m not the ideal person to talk about this, someone has to say something because the problem is huge. It is too big to ignore. There are only 56 African American women with PhDs in physics. I only know two black physicists in heavy ion physics, neither of them are originally from the US, and one is still a graduate student. We have to do something because it threatens the viability of scientific research. We are not recruiting the best and the brightest to the field.
This is a really complicated problem and I don’t have a solution. Changing this – inspiring young black girls and boys to pursue careers in science and technology – will not be easy. But we have to try.