Quantum Diaries

No, this is not a story about being stuck at an airport during the flight chaos last week. I was always expecting that one of the quantum diarists would report on this, but so far nobody reported. I hope that everybody is where he/she wants to be and not stuck at some far away airport.
But the topic is of course the volcano in Iceland and its consequences:
We organized the ATLAS Upgrade Week 2010 at DESY for last week. More than 170 people registered and were supposed to arrive last Monday. In the week before the meeting I was rather busy with the preparation but also other work. When they close the Hamburg airport on Thursday evening I did not even think that this could affect our meeting.
But the longer the airports were closed, the more I started to doubt that people come to Hamburg. During last weekend it was decided that the meeting will start anyway and that people should join via EVO (meetings where people can dial in via computer or a phone bridge). Originally we had planned only very few EVO meetings but now we had to adjust. Luckily DESY is a large national lab and we have the facilities for this kind of meeting. On Monday morning I contacted our IT group and told them, that we have to rearrange due to the changed situation. And within no time, we had arranged the meeting rooms and the colleague at IT booked EVO meetings for the whole week. I implemented the links in the agenda and we were ready to start.

Almost 100 people had to cancel as they could not reach Hamburg. Others arrived one or two days later. So we thought that we should reward some people for the most strenuous journeys with a little award. One person needed 18 hours per train from Udine. Another person flew in from Israel and had long delays during the trip. But the first place was won by a group from Liverpool. They actually took the train through London, Paris, Strasbourg, Karlsruhe to Hamburg. 20 hours with 5 changes is not really the best connection between Liverpool and Hamburg. I hope they enjoy the German wine and remember Hamburg as a sunny nice place.
In the end all participants were happy that we still could discuss important issues and I think the “DESY volcano meeting” will be remembered for a long time.

While everybody else is reporting on the possibility of white Christmas, I am actually sitting in shorts and T-shirt while typing this blog entry. Today we have 33 degrees plus and in two days I will be on the beach. A few days ago I travelled with my husband from Hamburg through Paris and Rio de Janeiro to Porto Alegre in the south of Brasil. My husbands family is living here and we are going to spend Christmas and New Years with them. And afterwards we will stay a bit longer as this is actually my summer vacation. With a family in the souther hemisphere it is not the first time we go on summer vacation during the European winter, but it is the first time over Christmas. And this is really strange!
Porto Alegre is the capital of the southernmost Brazilian state Rio Grande do Sul and one of the biggest cities in Brazil. The city was founded in 1742 by immigrants from Portugal. In the late 19th century the city received many immigrants from other parts of the world, particularly Germany, Italy, and Poland. The vast majority of the population is of European descent. Therefore the city is a very interesting mix of Southern American and European charme. Most people who have not been to Brazil think only of Carneval, the Amazon or beaches. Or people ask me if I was robbed already. Of course this are very limited pictures of such a huge country and I only can speak for the South of Brazil.
Here in the South, Brazil is a very prosperous modern country with a good economy. Porto Alegre is the city with the highest living standard in South America and this is visible all over the place. I love to be here as the Brazilians are the friendliest people I ever met. They always want to make sure that everything is perfect for us and that we spend a very nice holiday. And not only the family members are caring, but just everybody we meet. When we ask for help (for example to find the way) the people are very eager to help. And if we do not understand, as our Portuguese is limited, they take our hands and show us the way.
Now is the first Christmas we spend here in Brazil. For us it is of course very unusual to think of Christmas and Santa Claus in the middle of the summer. The Christmas decoration is usually very green and the use of artificial snow is not common. As they don’t have that many fir trees here, the typical Christmas tree is a pine tree, or a lot of people have artificial Christmas trees, as the fresh trees don’t stay fresh in this heat. These are my very first impressions of Christmas in Brazil upside down and I think I have to report later on again.

Following the press coverage of the LHC startup is quite entertaining. There seem to be journalists sitting in front of the computer watching any tweet or blog where they might catch some information about something going wrong at the LHC. Or they assume something is wrong with LHC when the web pages are not online or anything out of the ordinary happens. A power cut at LHC makes it very easily into breaking news these days.
Therefore I decided to write about power cuts in the daily life of an accelerator and the experiments. A power cut is a nuisance, but it is part of life when working in particle physics. One has to understand that most of the power cuts are due to safety measures in the whole system. If the current in the power system fluctuates – maybe due to a small problem in the power plant, or it’s the half time of a soccer game and many fridges are opened at the same time to get out the beer – it might happen that our power supplies trip. A power supply is the device between the power outlet in the hall and our detector and in particle physics and it regulates the voltages and currents for our detectors and magnets. These devices were usually specifically designed for exactly the system they serve. Tripping means that the voltage is quickly ramped down because some over-current was detected. With these safety measures, we can make sure that detectors (or accelerator sub-systems) are not damaged when something unusual goes on. And this system is very fast. For example if at home the light flutters due to a glitch or fluctuation in the power system, the TV does not even show that there was a problem. A particle accelerator or a huge experiment would already be shut off just for safety reasons in the moment the light at home just flutters.

Power cuts are normal. Everybody who worked at PS, SPS, LEP or HERA (I guess it is the same at Tevatron) experienced more than enough power cuts.
And what happens then? Within a fraction of the second a lot of power supplies around the accelerator and/or at the experiments are turned off. Then we cannot just turn one switch and everything is back on. It is just normal that it takes some hours, as we first have to see why things were turned off, which parts of the things were turned off etc. When this is established, people have to start switching everything back on, usually in a certain order. And it case of the power cut there can be many devices in a funny state. Mostly they can be reset remotely using software, but sometimes more than a soft reset is needed. It can be that some of the supplies might be on the other side of the accelerator, in case of LHC some km to drive – someone has to get up, (get dressed if the power cut is in the night) and drive there. For example when I was in charge of the ZEUS calorimeter, almost every time when there was a thunderstorm in Hamburg (a usual weather condition in summer)the lights went out in HERA and the experiments. I don’t have an exact statistics, but on average it took something like 6 hours to recover from a power cut.
In case LHC is down due to a power cut for some hours, it does not mean that it is damaged or a bird from the future was harming it. It is normal daily business and we have to live with it….

With all the excitement about the LHC startup and the first paper, other things were falling a bit behind recently. But not all Quantum Diarists are 100% working on the LHC and have to get back to the normal business while keeping a close eye on what is happening at CERN. I am actually right now exactly at that place to do something down-to-earth thing like packing up “my” telescope. After running 22 weeks at CERN with 11 different users from LHC to Linear Collider groups, the telescope is packed into two big boxes to be shipped to DESY for its well-deserved hibernation. The hibernation time is actually rather short, as we will have to put it back together at DESY before the February test beam. Since the packing up and finding all the bits and pieces went a bit faster than originally planned, I had the chance to go to an interesting event in the main auditorium (only the first half day).

“The From the PS to the LHC: 50 Years of Nobel Memories in High-Energy Physics.” On the agenda of the 1 ½ days symposium are alone 13 Nobel laureates from Jack Steinberger to Steven Weinberg, and many other very interesting speakers. I have never seen that many Nobel laureates in one place in my life. Ok, seeing Nobel laureates is not something I do every day anyway… so far I have heard talks of two (Richard Taylor and Martinus Veltman), already some years ago and not at the same time. The nice thing is, that there are that many Nobel prize winners in particle physics which are still healthy enough to come to CERN for such a symposium. And these are not the only laureates. In the last 50 years very regularly this highest possible science award went to particle physicists – showing also the importance of this field for fundamental research. I listed the awards below and hope I did not forget anybody. And I am very curious who is going to be the next laureate in particle physics!!

1960
Donald Arthur Glaser for the invention of the bubble chamber.

1961
Robert Hofstadter for his pioneering studies of electron scattering in atomic nuclei and for his thereby achieved discoveries concerning the structure of the nucleons.

1965
Sin-Itiro Tomonaga, Julian Schwinger, and Richard P. Feynman
for their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics of elementary particles.

1968
Luis Walter Alvarez for his decisive contributions to elementary particle physics, in particular the discovery of a large number of resonance states, made possible through his development of the technique of using hydrogen bubble chamber and data analysis.

1969
Murray Gell-Mann for his contributions and discoveries concerning the classification of elementary particles and their interactions.

1976
Samuel Ting and Burton Richter for their pioneering work in the discovery of a heavy elementary particle of a new kind.

1979
Sheldon Lee Glashow, Abdus Salam, and Steven Weinberg for their contributions to the theory of the unified weak and electromagnetic interaction between elementary particles, including, inter alia, the prediction of the weak neutral current.

1980
James Cronin and Val Logsdon Fitch for the discovery of violations of fundamental symmetry principles in the decay of neutral K-mesons.

1984
Carlo Rubbia Simon and van der Meer for their decisive contributions to the large project, which led to the discovery of the field particles W and Z, communicators of weak interaction.

1988
Jack Steinberger, Leon Lederman and Melvin Schwartz
for the neutrino beam method and the demonstration of the doublet structure of the leptons through the discovery of the muon neutrin.

1990
Jerome I. Friedman, Henry W. Kendall, and Richard E. Taylor for their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics”

1999
Gerardus ‘t Hooft and Martinus Veltman for elucidating the quantum structure of electroweak interactions in physics.

2004
David J. Gross, H. David Politzer, and Frank Wilczek for the discovery of asymptotic freedom in the theory of the strong interaction.

2008
Makoto Kobayashi and Toshihide Maskawa for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature.

AND (also 2008)
Yoichiro Nambu for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics.

These are really different times and so exciting! I am sitting at home in Hamburg, actually supposed to work on a talk. But I am constantly staring at the online version of the LHC beam display, any other online feed I could find, and also Pauls comments here on QD. And this is really exciting! Also my husband is asking all the time what the status is and how many turns were done.
You can also follow all the details on Twitter, as anounced earlier today by the DG. Hope you all stay tuned to follow this in the next days, weeks, months and years to come!!

As you might have figured, we are again at the same meeting, Frank and I: The 3rd Annual Meeting of the Helmholtz Alliance “Physics at the Terascale”.
The Terascale, already explained in April by Frank (and I am not allowed to copy and paste 😉 ) is a structured research network as a tool for a more effective collaboration, in particular between experimentalists and theorists. The name Terascale was chosen as the network is focusing mainly on LHC and Linear Collider physics, both machine running at very high energy. Eighteen German universities, 2 Helmholtz institutes and 1 Max Planck Institute (Munich) are part of this alliance.

More than 250 people decided to visit DESY for this meeting, also a lot of students and post-docs. Today is already the last day, we started Wednesday afternoon with the program. There were many different meetings to exchange the status and experiences of particle physics at the Terascale in Germany.
Setting up such an infrastructure in Germany is not an easy task, as the universities are free and used to do their research independently. Of course this independence is conserved, but now new ideas to exchange knowledge were introduced. For example a new group was founded all working on SiPM (Silicon Photon Multipliers) to make sure that the understanding of this new devices is enhanced by a lively exchange of new results. And combined studies are also part of the plan.
For both evenings a social event was planned, a reception with Arabic food on Wednesday and a Italian dinner on Thursday. As physicists, especially students, have the tendency to take a lot of food at a buffet and empty a buffet within minutes, the dinner opening speech on Thursday included some explanation how to approach the buffet. -Take a small plate only for the starters and come back for a large plate for the main course. “Do not take starters and main course at the same time.“ This was also said to make sure that all people do get a dinner, as it is sometimes the case that people lining up last, only find empty pots.
It seemed to have worked out quite well as we all had starters (on a small plate) and a main course (on a large plate). Unfortunately it was not mentioned to use only the small desert plates for the desert. People were seen piling a huge mountain of chocolate mousse on standard dinner plates. In the end the starter and the main course worked out fine, but only a few people could enjoy the desert. So there is room for improvement in respect of dinner manners. When we arrived at the buffet, we only could see that there used to be some chocolate mousse….
Frank actually wanted that I use the word “naked” in the title. But looking at the weather outside, I could not think of something where one can be that lightly dressed. It is very typical Hamburg November weather with all kinds of clouds and raindrop sizes. And after the chocolate mousse disaster, I think Frank would have loved to have access to a chocolate factory within the Terascale Alliance – the latest German infrastructure for particle physics.

On Saturday there was the open day at DESY in Hamburg in conjunction with the science night in Hamburg. More than 13000 people visited DESY to take a look at the large science center. As I was still travelling until Friday, I was not involved in the preparation of the open day and therefore was surprised to see what was prepared. The open day was masterly prepared so that nobody gets lost on our site. Every visitor received a small map where the buildings with things to see where highlighted and even a bus shuttle service was in place to bring the people quickly from one end to the other. What I liked a lot where the colored spotlights giving some different look of buildings or trees – a very nice atmosphere.

One of the experimental halls of the former Hera accelerator – Hera West – was being prepared for public tours recently, and of course part of the exhibition on Saturday. In the hall different samples of high energy physics detectors were on display, the biggest being the Hera-B experiment itself.
The visitors also had the possibility to walk the ~1.5 km from the Hera-B experiment to the next Hera experiment H1 through the Hera tunnel (25m under ground). This was a very popular tour and people were lining up for up to one hour to get down to the tunnel.

I think it is very important for scientists to talk to non-scientists once in a while and to try to explain what all this is about in a language understandable for non-scientists. After all, our science is funded by tax money, paid mostly by non-scientists. So we owe the tax payers a good explanations why we need all this huge machines and fancy detectors. I spend a few hours in the Hera-West hall close to some of the exhibits answering questions. As most people visiting such an open day are very interested and open-minded, the discussions are lively and fun. And the people also have a lot of real good questions. I usually have a lot of fun and enjoy the discussions with people from all different backgrounds. Open days are a great invention!

Last Saturday I went with two friends to Kennedy Space Center at the East Coast of Florida. We left Orlando in the morning and drove the roughly 80km to the West coast.

It was a beautiful day with blue skies and a lot of sun. Late morning we arrived at the Space Center and we could directly enter as there were no line ups.
At 11:00 we went to the auditorium where an astronaut gave a talk on being an astronaut. It was very interesting as he was Alfred Worden, one of the Astronauts of Apollo 15* mission. His two colleagues actually touched the moon while we was circulating around the moon to study the lunar surface and environment in great detail using a panoramic camera, gamma ray spectrometer, mapping camera, laser altimeter, mass spectrometer, and lunar sub-satellite that was launched at the end of the mission.
While he was talking on Saturday very detailed about many aspects of such a journey to the moon (eating, sleeping and whatever in outer space), I was always trying to realize that there is a person standing in front of me who was once behind the moon and back. Even so I know that this is reality, it is still amazing what mankind can do. Especially keeping in mind that all technologies where at a rather different stage than nowadays.
After the “meeting with an astronaut” we took a tour bus to different stations on the huge areal of Kennedy Space center. The areal is actually 55km long and 10 km. We were told more than once that about 5000 alligators would be living in the area. But we did not see one. One stop was a look out point to the shuttle launch spot. We could not go much closer as the Atlantis was actually parked there as it is supposed to be launched mid November. Really cool to see a shuttle in reality (even so it was hard to see)!
Later on we went back to the main center and did a shuttle start simulation. That means we were in a simulator seat (many people together in a bus-like shuttle) and we were told many time before it started that it would be the most realistic shuttle simulation and that we would be doing the same movements under almost real condition as a person sitting in a space shuttle during a launch. I actually started to worry that I would get sick as I expected it to be rather rough. After some time the countdown of the last 10 seconds started and we were launched. The first two minutes were really shaky and loud, but then we were in outer space … It was real fun, but I think they softened it a bit to avoid that people get sick. A shuttle start cannot be that smooth!
All in all it was very interesting and fascinating to go there and if you ever get to go to Florida, don’t miss the Kennedy Space Center.

*Apollo 15 was the ninth manned mission in the Apollo program, the fourth mission to land on the Moon and the eighth successful manned mission. It was the first of what were termed “J missions”, long duration stays on the Moon with a greater focus on science than had been possible on previous missions. The mission began on July 26, 1971, and concluded on August 7. NASA called it the most successful manned flight ever achieved.

This is for sure true here at the conference. As Frank already pointed out, it is very cold in the conference centre while we have a beautiful summer day outside. I am also wearing a long sleeve shirt and regret very much that I left my fleece jacket in my room.
So I am also in Florida, at the IEEE NSS/MIC conference. This conference exists since more than 50 years and was established when instrumentation for the detection of particles and ionising radiation became a necessity. They started out with a rather small group of people. Many years this conference was held one year in San Francisco and the other year in Norfolk, the largest Navy base in the US. Only in 1998 they decided to go with this conference outside of the US and held the conference in Toronto, Canada. That was actually the first time I came to this event. Since then this conference changed into a travelling meeting. We were in Seattle, Lyon, San Diego, Norfolk, Portland, Rome, Puerto Rico, Hawaii, Dresden and now Orlando in Florida.
What does NSS/MIC mean? It stands for Nuclear Science Symposium and Medical Imaging Conference. Yes, Nuclear! When asked at the US border what conference I would be attending while being in the US, I usually say “Medical Imaging Conference” as the word “nuclear” always makes this guys nervous and might result in a lot of questions. Medical sounds really harmless.
But by nuclear one means everything related to detection of particles. And it is a large field. Here one meets not only particle physicists, but also people working at nuclear plants, in hospitals or people from the army. And this makes it even more interesting, to learn from completely different communities.
Yesterday for example I talked some time to a medical physicist and learned why they build this tiny little PETs*. Those small-animal PETs are for clinical studies at rats. For example when a cancer medication is tested, the rat can be placed in such a device and the impact of the medicine can be studied live using this device. Developing such a mini device is not as easy one would think. This conference is, besides many other topics, the place where experts on these devices meet and exchange their experience.
Important are also the evenings here. The last couple of days we were sitting outside close to the pool and met people from all over the world. As I attend this conference since 10 years, I have a lot of friends who I meet only once a year. But then we always have a nice time and exchange a lot of different view on science in the different fields.

By the way, the title of this blog was actually driven by a scientific talk. On one slide in a presentation on silicon detectors we (Frank and I) saw a picture of a silicon chip after dicing
and before it is attached to any other electronics – the speaker labeled that picture with “the naked die” …. our association was more in the direction of freezing in this building when not dressed sufficiently.

* PET positron emission tomography is a nuclear medicine imaging technique which produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule.

Clearly, it is meeting and conference season! A lot of the recent blog entries were about interesting meetings at nice places around the world.
One of the nice meetings each fall in the last few years is the EUDET annual meeting, currently ongoing at the University of Geneva and CERN. Yes, I am in Geneva again. But as the first two days of the meeting are at the University, I get something else to see than the CERN site. I was reminded ones more, that Geneva is a beautiful city. And the weather (cold but sunny) was having an additional positive impact.
The University of Geneve is actually already 450 years old and the meeting are taking place in a nice older building with a classical auditorium. Martin Pohl, one of the organisers of this meeting and professor at this University, gave an overview on science in Switzerland and especially in Geneva. And with this talk he convinced us impressively that Geneva is not “only” the home of CERN.
The EUDET meeting is 2 1/2 days long. On Monday, the first day, we spend all day in parallel sessions to have the opportunity to discuss our joint research activities in detail. In “my” session we talked all day about the EUDET telescope and its future and also had a number of telescope users reporting on their experiences and their first results. We had a lively discussions and I think all of us learned something on Monday.
Yesterday and today are filled with plenary sessions with overviews on all this activities, but also some view to the future. EUDET is now in its forth year and will be finished at the end of 2010. So we started already some time ago to discuss what could follow after this. And this is of course the main topics during the coffee breaks or also at dinner as we have to get the proposals for this future ready in the next couple of weeks.
Last night we had the conference dinner. A conference dinner is not just a dinner for eating something nice, but at the dinner you can get a feeling for a collaboration. You meet people in a relaxed atmosphere and get to talk in a
less surrounding. Our hosts in Geneva selected a very nice venue, the restaurant “De L’arquebuse La Broche”. This is actually a place I would never go to when being in Geneva as from the outside (and also inside) it looks so Posh that I would be afraid to loose a considerable fraction of a month’s salary to pay my dinner. But our host must have found a way to convince them to offer a nice dinner for all of us for a still reasonable price.
And we had reason to celebrate. The EUDET project was proposed roughly 5 years ago. The inventors at that point thought of a nice program to enhance the infrastructure for detector research towards a linear collider within Europe. At this year’s meeting we could see that we reached alread 95% of the goals set 5 years ago! And we still have some time to reach the remaining 5%. A very good reason to celebrate!