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Chamonix: What The LHC Experiments Will Be Doing This Summer February 3, 2009

Posted by gordonwatts in LHC.

LHC_magnet[1] Wow – I didn’t realize how many meetings there were going on this week! In ATLAS there is the trigger workshop I’m attending in Beatenberg. I know of a Liquid Argon Calorimeter week going on in Marrakesh (lucky bastards!). The Chamonix meeting, however, is the one where everyone wishes they could be a fly on the wall at.

Every year for years and years (going back more than 20 years, I’m given to understand) the CERN accelerator folks decamp to Chamonix to discuss all things CERN accelerators (perhaps to do a bit of skiing to!?!?). CERN is large and quite active – with more than the LHC going on, so they have a lot to discuss! Of special interest, of course, is how they will manage the startup for the LHC.

The current date for startup is this summer — July. That is subject to change, of course, if they find a problem with the ongoing repairs. The news I’ve heard of the repairs has been quite smooth – though I’m not really plugged into the rumor mill. So perhaps that July date will stand – which would be great.

But there is a lot more to decide than the start up date. What energies will they try to run at? How many protons will they put in the machine: how intense will they make the beam? How fast will they ramp the energy and intensity up? Heck, how long will they experiment with single beams before they try colliding beams?

From the experiments point of view, the most important a few collisions (at least in my opinion). It almost doesn’t matter what energy they are at. Even just a few days would be a huge help to commission the detectors. We’ve taken 100’s of millions of cosmic rays now – we know a lot about the basic performance of a substantial fraction of the detector. But the trigger and timing ourselves to match the LHC’s collisions is hard! We all guess there is a lot of work there. And any data at all would be a huge help. The process is sort of like diminishing returns: the first dollop of data lets you get the big things right, the next the next most important things are tuned up, etc. And what is worse is those first fixes are usually the largest and require the most time – imagine if we’d had a few days of collisions last September. Wow – we’d be so much further along than we are today (or we know that we were so much further along if everything had worked)!

Of course everyone wants to do physics as well. There the experiments will probably push for higher energies – if the LHC will accumulate only a small amount of data those higher energies are required to give any competition at all to the Tevatron. Of course, the LHC may want to operate at lower energies to keep things safe.

We’ll see what they say…


2009. Ready or not January 2, 2009

Posted by gordonwatts in ATLAS, CERN, D0, Fermilab, LHC, politics, science.

We’ve made it through the first day of 2009. I have mixed feelings about this coming year.

  • Federal Science Funding Levels. The economy is crashing down around our ears. Business responds quickly (layoffs :() – government is a bit slower. If things followed their natural course of action that would mean science funding, along with everything else, will take yet another hit. However, the incoming Obama administration seems to be committed to spending the USA’s way out of this recession, so in the end funding might not change very much. I am hopeful that hard sciences funding will remain at least stable.
  • Federal Science Funding Directions. Climate change is what the Obama administration is focused on. There is a good chance that if you are researching something connected with climate change you may have access to increased funding opportunities. I would expect a funding profile similar to NIH’s funding during its years of increase. I would like to think that funding will spill over into the physical sciences – it should because there are connections between the physical sciences and clean air technologies. All of this is applied scientific research. I hope that the pure research funding gets an increase as well, as an investment in this countries future (particle physics is pure research, of course). I’m feeling neutral here.
  • Federal Science. Obama’s science team is just a BLAST of fresh air when compared to the current administration’s. After all, his DOE nominee is a Nobel prize winning experimental physicist. Even if the science advisor isn’t elevated to a cabinet position (PDF), there will be someone in the room that knows a great deal about science, research, and how it is done. Even if there are cuts to science funding, I’m very hopeful there will be intelligent cuts rather that unscientifically motivated cuts. I’m very hopeful in this respect.
  • State Universities. The economy in states is depressing. Some states, like my own (Washington) that rely on sales tax are being hit hard and very fast. State universities can’t escape that, obviously, and my university is no exception. Unfortunately, this usually translates to reduced raises, inability to counter offers from outside, reduced support for research, etc. In our own department I wouldn’t be surprised if some people left for other universities that, for whatever reason, were able to make good offers in this awful climate. There is, in fact, already evidence this is happening. The only consolation is most universities are in the same boat, and so most of them are having similar problems. I know less about private universities, but I do know the endowments of many of them are also having difficulty. I’m very downbeat about this: it will be a rough two years at least, I think.
  • My Science. When it comes to the Tevatron and the LHC… Well, I see no reason that the Tevatron shouldn’t continue to break records in luminosity (they just broke one earlier this week). And the experiments will continue to be flooded with data. While it is possible for one experiment or the other to have a catastrophic failure, I doubt that will happen. And they should continue to produce papers and science at a furious rate. I also am looking forward to real LHC collision data this year. While I hope it will be at the full 14 TeV, I suspect it is more likely to be at 2 TeV, just a hair above the Tevatron’s luminosity. We’ll hopefully know what the machine scientists think about that sometime in February. I’m really hopeful about this.
  • New Years Resolutions. Well, I made only one. That way I have a hope of keeping it: make bread more often. 🙂 I think there is a chance that I will keep this one. Especially now that I’ve said it publically. 🙂

Of course, this should also be a fun year, as noted by the Beacon News:

Frustrated with their failed attempt to destroy the world in 2008, the scientists at Fermilab and their counterparts at Switzerland’s CERN physics lab resolve to perfect their new device, the Large Planet-Sucking Black-Hole-o-Tron.

Here is to another great year of data collection and science at the Tevatron and first collision data at the LHC!

Some Official Information and Even Pictures December 5, 2008

Posted by gordonwatts in LHC.

image Robert Aymar is the outgoing Director General of CERN. He gave a recent update of CERN accelerator activities at the ECFA conference. It is a complete update, but there are a few pages in the middle with information on the current state of the LHC. And – lo!!!!! – pictures. Just two. And no ice is visible. I’ve extracted one of the pictures and put in here. That is the link between two magnets – normally the two magnets should be totally lined up.

There are three mitigation strategies that he lists in this talk:

  • Improve the quench detection system. The improved sensors will help better localize problems as well as detect them a bit faster.
  • Add relief valves all around the accelerator. If such a disaster occurs again then these releif valves should prevent the violent pressurization that occurred and caused such a lot of damage (like the moved magnets shown above).
  • Better anchoring of the magnets. So if there is another pressure build up the magnets are less likely to move!

He also mentions two other inter connects similar to the one that failed that have an abnormal resistance – but their resistance is thought to be much less than the interconnect that failed. In ATLAS we’ve been having to evacuate the cavern due to numerous electrical tests of the LHC when they were localizing these. Nanohoms. So small! 🙂

Unfortunately, there is no real mention of schedule in this talk. It is nice to see something that is officially public. This matches the talk I saw on Monday, but, of course, it looks like CERN has made it officially public. It would be nice if they would do the same thing to that other talk too.

What is sad about this is I found this out from a news posting in DZERO, which was linking to a USLHC blog. Why did it come to me that way!? They can do a little better!!

The LHC turnon December 3, 2008

Posted by gordonwatts in LHC.

Last week there was a talk at an ATLAS meeting that got wide coverage in the blogosphere. The talk, by Jorg Wenninger, was full of detail, and Not Even Wrong did an excellent job of summarizing the talk.

One thing that worried a lot of us was picked up by Peter in his posting:

There is also a plan is to add pressure release valves on every dipole cryostat, but this is highly problematic since it will require warming up all the sectors and likely would not allow the LHC to run with beam during 2009.

As we saw in a meeting here at CERN earlier this week, that turns out not to be entirely true. They can actually add pressure relief valves to the LHC magnets while they are cold. They can do more to the warm sections, but they can do enough to the cold sections to make it capable of withstanding a massive quench like the one on September 19th.

This extra information is nice because it means that when CERN talks about starting to run in summer 2009 it doesn’t mean the accelerator will be in danger of a similar disaster. My impression is sometime in early February there will be a final discussion on exactly what the run parameters will be, along with a startup date more precise than July 2009. I also suspect there won’t be any further news before then. BTW, during this talk it was commented that they have already started to replace the damaged magnets. Nice to see them working so fast, though I suppose they have to in order to meet the fairly aggressive schedule of startup next summer!

The LHC did make BlackHoles October 7, 2008

Posted by gordonwatts in LHC, life.
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This joke was told to me by the father of a friend at a 1-year-old birthday party. He isn’t a scientist, but, like many people, fascinated by the science that is going on.

I see the LHC did produce a blackhole after all! It just drifted over to wall street and is starting to swallow the universe there…

I’m sure we can rewrite this to make it better – but the idea is just too good to not write it down…

LHC To Be Opened This Weekend October 3, 2008

Posted by gordonwatts in LHC.
1 comment so far

Well, I may not be getting my gossip from blogs right now, but my email still renders it. I’m given to understand that Lyn Evans, head of LHC operations, said that they will finally have access to the tunnel this weekend at the LHC conference in Split – so they can figure out exactly what went wrong. He gave a talk there, but this information came during the Q&A session. Further, from their preliminary examination they have enough magnet spares to replace everything that looks like it might have been damaged. That is very good news. Next week is ATLAS week and Evans is scheduled to give another talk there – perhaps he will have more details by then. Sadly, that meeting isn’t public so even if he does post slides I can’t point everyone to them!

That Is Just Sad September 24, 2008

Posted by gordonwatts in LHC.

When I searched for “Large Hadron Collider” on google the other day it told me:


I suppose any press is better than no press!

Will There Be LHC Beam This Year? September 23, 2008

Posted by gordonwatts in CERN, LHC.

Well… I wrote this post last night – before the press release that arrived in my email this morning at 10:50am (pacific time) – there will be no beam in the LHC until early spring… I’ll leave the rest of the post below, though I don’t know if it has any value at this point… But I’m too lazy to write a new one!

I’m not privy to inside information (if I was I wouldn’t write this post!). But you can do the following calculation yourself.

The LHC is going to be down for 2 months. That means the machine will be cold and ready to start power up in mid November. The current winter shutdown will probably commence at the end of November. That means only two weeks of time to power the machine up, put beam back in, try collisions (at 900 GeV), sync up the RF system and perhaps try acceleration. 900 GeV, by the way, is the beam injection energy: one doesn’t have to commission the whole acceleration sequence in order to run the LHC at 900 GeV.

Not a lot of time. From the accelerator point of view I’m not sure it makes sense. ATLAS and CMS, as well as others, however, are probably dying for any data they can get their hands on. They have had a taste, but even a week of collisions at 900 GeV would go a long way to helping with the commissioning. That isn’t to say that both experiments won’t have plenty to do during the winter shutdown even if the collisions don’t occur. I believe both will want to open up their detectors and get inside to the parts that are not easily accessible, for example.

Finally, there is politics. Closing out the year without collisions will be “a tough beat”. The newspapers are watching everything we do and they will surely report on this as a disappointment. Scientifically (given the information I have – which is the same that everyone else has and is undoubtedly not complete), it seems like the case for beam this year is on thin ice.

This whole post is based on the premise that the problem that occurred is as the LHC accelerator division expects: something that will take one or two days to fix. If a magnet needs to be swapped out with a spare or something similar to that, then I’d guess we will almost certainly not have beam. We should have the answer to that question as soon as they have a look inside the magnet, which will occur when it is warm in a little less than a month. As CERN has said:

“It’s too early to say whether we’ll still be having collisions this year,” said James Gillies, chief of communications for CERN, in an e-mail message.

The winter shutdown is due to the very high electricity costs in Geneva. I’m used to electricity use spiking in the summer as everyone turns on their A/C. Anyone know what causes the high cost in Geneva during the winter?

Every Move You Make… September 23, 2008

Posted by gordonwatts in LHC, press.
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Here is a bit of news that showed up on CNET:

The European Organization for Nuclear Research, or CERN, the organization that built the LHC, announced Thursday that a transformer that helps cool part of the collider had malfunctioned, forcing operations to be suspended.

Think about that for a minute. CNET – a tech web publication – is following the ups and downs of the LHC. Have we ever had that level of interest in a HEP experiment before!? Not that I’m aware of. I remember the Fermilab start-up and even then no one tracked it like this.

One thing about the article:

No word on why it took CERN so long to let us know about the malfunction, though.

I don’t know for sure, but I can guess: they aren’t used to this level of press interest. So telling the press exactly what is going on with the machine gets done after everything else is taken care of (how to fix, implement the plan, etc.).

I wonder if they will have the latest magnet quench web page? We should write a desktop widget which has LHC status. 🙂

LHC is Turning on FAST September 19, 2008

Posted by gordonwatts in Fermilab, LHC.

During Frank’s talk he said that he was a bit "depressed that it took 25 years to build machine, but just a few weeks to commission" – implying it wasn’t enough of a challenge.

I am, frankly, amazed at how fast this thing has turned on. None of my previous experience had prepared me for how fast they have turned on. The engineering job is incredible. Here they turned on 10 September and they are talking about first collisions (at 900 GeV — really small compared to the planned 14 TeV final operation) this coming weekend!

Given the number of moving parts, electronics, etc., in this machine… well, this is a breath-taking to have gotten this far. As a long-time member of the US community I’m also feeling a bit embarrassed. Our last start up – Fermilab Run 2 – was not nearly as smooth. One key difference between the LHC and Fermilab’s startup, btw, is that all the bits are present in the accelerator from the get-go. Fermilab has continuously been adding bits to the accelerator to improve it (many bits were delayed due to the funding profile).

If we in the USA get a chance to build another accelerator we are going to have to make sure we step up and match (or come close to matching) CERN’s accelerator division!

UPDATE: Yeah Yeah. I know. 2 months of downtime now. 🙂 What can I say? The accident was probably caused by me posting this. I don’t know if you saw the CERN press release – but note how it said that in a non-super conducting machine this fix would take a few days? The 2 months is because they have to warm the machine up and then cool it down again. What is a magnet replacement at Fermilab? 8 days? I wonder what the difference is in the cryo systems?