Author: Stephen Sekula

Steve Sekula is an Assistant Professor of Experimental Particle Physics at Southern Methodist University. He earned his Ph.D. from the University of Wisconsin-Madison in 2004, and currently spends most of his time either conducting research into the Higgs boson on the ATLAS Experiment or teaching. Oh, and he blogs. We all have flaws.
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To CERN: messages from today, messages from 1980

Next week (June 2-6), I will be at CERN for the first time in many years (and to kickoff my many visits to come!). I am attending the ATLAS Collaboration Physics Week, a four-day event centering on ATLAS physics analysis. I am excited to be heading to the new Mecca of particle physics, the new global hub that will soon define the frontier of collider physics.

In the spirit of that new frontier, I had a very interesting conversation today at lunch. A senior SLAC theoretical physicist started discussing the very interesting evidence that he thinks is mounting for significant contributions to the proton from charm and bottom quarks. Called “intrinsic charm” or “intrinsic bottom”, these contributions mark the ultimate in quantum mechanics. In the classical physics view of the proton, the quarks rattle around inside glued together by the strong force. Quantum mechanics, which accurately described the proton and crushes the classical picture, instead tells us that the proton is mostly NOT the three quarks that define it. It’s mostly gluons, and in fact those gluons are constantly producing pairs of virtual particles that flit in and our of existence and contribute significant structure to the proton. Even in that latter picture, the basis of all computation, there are assumptions about how much you can ignore charm and bottom that may be proving to be wrong.

That more common view sees the contribution of intrinsic charm and bottom as negligible. But, in the high energy environment of leading hadron colliders – the Tevatron and soon the LHC – that picture may be incorrect (c.f. [1,2]). In fact, a recent D0 preliminary result [3] suggest that the proton/anti-proton collision debris close to the beamline (at large rapidity) exhibit behavior that greatly differs from the leading calculations of these collisions. These calculations are provided in the Coordinated Theoretical-Experimental QCD (CTEQ) parton distribution functions (PDFs) [4]. The D0 authors state that the version of CTEQ PDFs used in their comparison do not include the Tevatron Run II data results, so they represent a pre-Run-II picture of QCD at hgh energy. Their data suggests that picture needs updating.

The picture painted at lunch today was of this rich universe of phenomena lurking just inside this deceptively simple picture of the proton. Looking back at some papers on this, I also realize that we are entering an era where these ideas that seemed, perhaps, so far off in 1980 (ala [1]) are on our doorstep now, demanding attention. In the fight to understand the Standard Model, so that we can see beyond it, such issues will become more and more critical.

[1] S.J. Brodsky, P. Hoyer, C. Peterson and N. Sakai. Phys. Lett. B 93 (1980)

[2] http://arxiv.org/abs/hep-ph/0508126

[3] http://www-d0.fnal.gov/Run2Physics/WWW/results/prelim/QCD/Q14/

[4] http://www.phys.psu.edu/~cteq/

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sshfs – remote access for the terminal

In the world of modern HEP computing, your data analysis location may be on a computer far removed from your office. What if your analysis produces a bunch of plots that you want to be able to just look at without constantly transferring them to your local machine? What if you need to edit code that lives on a remote system and isn’t in CVS? How do you get interactive with remote files?

Many people do the following: they make a secure shell connection (SSH connection) to the remote machine. They then run applications on the remote machine which may pop up windows over the network. The overhead of showing windows over a network connection is HUGE, and often wastes the user’s time. Mounting remote disks using NFS or AFS is either a pain in the ass, or banned due to security restrictions. What can you do?

My go-to solution is SSHFS. This is part of the much larger FUSE program – the Filesystem in Userspace program. FUSE makes it possible for the user to realize the usage of a number of filesystem types without having to be superuser, and without compromising overall system security by requiring access to the kernel of the operating system. SSHFS is an implementation of a network filesystem using the SSH connection protocol.

The idea is simple. Using sshfs, you log into the remote machine and then the remote directory is locally mounted into a directory. You can then use local commands – window operations, terminal operations, etc. – to access the files across the network. For instance, if I make an sshfs connection to machine in Europe and want to edit a script, I run EMACS on my local machine and give EMACS the path of the file on my local disk, which corresponds to the remote file located in Europe. It’s no less secure than using SSH, and as long as you aren’t editing or loading multi-100-Megabyte files over a low-end broadband connection, the response is pretty snappy.

I use SSHFS routinely for editing and viewing files. Even for small ROOT analysis demands, I can use it. Obviously, if you have to analyze gigabytes or terabytes of data, this is a BAD idea. But for simple routine editing and file viewing, it’s a life-saver.

Here are some implementations of FUSE and SSHFS for different operating systems:

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Messages for the Community

Support for Science - Under Construction: Lisa and I are your SLUO Washington trip co-chairsThis past week, three user organizations joined forces yet again in a well-organized and well-executed act of science diplomacy and headed to Washington D.C. to carry messages to Congress. Messages were also received, and will here be delivered in a short form for the community to heed. A more detailed report of this trip will be formulated over the next week and made available to the community through the user organizations.

The trip included 49 participants, with about 25% from SLAC, 31% from USLHC, and the rest from Fermilab. We met with over 200 Congressional offices, including a significant number of even short face-to-face meetings with members of Congress themselves. In addition, we sent small groups to the President’s Office of Management and Budget and to the science agencies, NSF and DOE Office of Science. A few of us were also invited to have drinks after normal Congressional business with Congressman Bill Foster, who is a physicist with significant business experience and now represents Fermilab’s district.

Messages from Congress

The biggest message from the Congress as a whole is that they still very much believe in funding science. From the Democrats who clearly control the Congress, to the most fiscally conservative Republicans, science is seen as an investment worth making, well thought-out and well-managed by the agencies overall. They still support the America COMPETES Act that passed in 2007 and laid out a blueprint for doubling the combined physical sciences budgets of NIST, NSF, and DOE in something like 7 years.

There were other messages, of course, from a smaller number of Congresspersons but no less important. There are many in the general body of Congress who still do not understand the significant role of the DOE Office of Science in funding basic research that benefits the nation and their districts. They hear “science” and they think of NIH or NSF, not DOE. DOE is seen as a technology agency, not a research agency or a steward of research tools. We have a LOT of work to do here, both in the community and in the agencies themselves.

Another significant messages regarded our field. There are key members of Congress with significant understanding of particle physics who caution us that we must commit to sending our best and brightest to the agencies to do 5-10 years of service. This is needed so that well-informed and highly regarded members of the community are making policy, not just sitting back and complaining about it. Our field, mainly due to the way universities view such work and due to the way we as colleagues view that work, holds the best close to the vest and sends “failed” candidates, those who didn’t get faculty jobs or those who didn’t have exceptional careers in the field, to Washington. One member of Congress noted that this is a sure recipe for the destruction of our field, and change needs to happen.

A final message was this: this year may be an easy one, and next year may be much, much harder. That is because this is the year that Congress took out a huge mortgage on the future. Next year, if things don’t start to improve, they will wake up and realize they cannot afford the mortgage. They will panic, perhaps, and make cuts across the board. Science may not survive that, and we may yet again go from the boom to the bust, the kind of bust that causes 20% layoffs again. It is imperative that we keep the dialogue going about the centrality of science to the economic solution, hope for better times but plan for worsening ones.

Messages from Office of Management and Budget

The conversation at OMB this year was a more casual one than in years past. The strong message that came through this year is the President’s commitment to science, even in worsening times. That said, the plan is to keep the FY10 budget flat. This is because the science agencies are overwhelmed with Recovery Act and FY09 money, and flushing that through the system needs to happen responsibly at a time when they are crunched for staff. FY10 will be flat, but have the arc of Recovery Act money on top of it, effectively bringing it to the level of the America COMPETES Act. FY11 will see a growing budget again.

The other large message was about DOE’s Office of Science. While there is a recognition that some awakening is happening, there is still frustration that DOE is not managing its brand. Congress still doesn’t get what they do overall, and even the agency itself seems not to understand the breadth of its own program. Change needs to happen here if we ever hope to have the effective science policy the community deserves.

Messages from NSF and DOE

We are still digesting these, and while I was not personally present on the NSF visit I can say that they clearly made their priority of moving DUSEL forward a top one, and a big topic of the conversation. Underground science is a critical focus of the particle physics and astronomy program at NSF. There was some frustration expressed about how fast LSST is moving itself forward on private money, even a sense that they are dangerously ahead of the agency. I got this information second-hand, but it was clearly weighing on the mind of the person reporting it to me.

From DOE, we got a sense both of optimism and caution. The optimism is that things will improve in the country, and the path ahead as planned by the America COMPETES Act will hold. The amount of money being handled by the agency is being treated with caution of the same scale as the increase. There is a concern that if a bust follows the boom this year, universities might suffer, but the agency seems confident it can prepare for that scenario. The President has tasked the nation to spend more on science, and the head of the DOE has tasked the basic research parts of the agency to prepare for growth. We learned that the NASA community has expressed some concern that it’s not part of this focus, but the statement from the top has been clear: the physical science agencies will move ahead.

Summary

Be positive, but proceed with foresight and planning. Know that science is at the top of the nation’s priorities, but we lack a firm champion in the Senate. The science agencies stand ready to deliver, albeit in the face of extreme scrutiny and without the personnel to do it as quickly as is preferred. Prepare for next year, and keep in touch with Congress so they don’t forget we are people too.