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Archive for September, 2011

The limits of science

Friday, September 30th, 2011

– By Byron Jennings, Theorist and Project Coordinator

Many minds, great, mediocre, and small, have pondered from time immemorial the ultimate nature of the universe. They were all searching for the same thing: the answer to the ultimate question of life, the universe, and everything. Naturally, being people, and having no real criteria to decide on the correct answer, they came up with a collection of contradictory answers, including:

  1. Materialism: The idea is that what you see is what you get. There is no man behind the curtain manipulating things. In this view, the mind and consciousness arises from the material brain.
  2. Idealism: Largely the converse of materialism. Here the mind is fundamental and the material objects only exist in the mind.
  3. Solipsism: An extreme form of idealism that says that all that exists is my mind. You are out of luck. Or vise versa. This one appeals to me since it makes me the center of the universe.
  4. Deism:  Materialism with an Omphalic twist. God or gods created the universe and then took an extended coffee break. This tended to be the default view of intellectuals in the age of enlightenment, most notably Thomas Paine (see The Age of Reason).
  5. Theism: God or gods created the universe and stayed around to interact with their creation. This is typical of western religions – Greek, Roman, Germanic, and the Mosaic religions.
  6. Orwellianism: Reality is what the Party says it is. The idea that there is reality apart from what the Party says is a pernicious superstition. This is the extreme case of ideology trumping everything else.
  7. 42: If you do not understand this answer you do not know what the question really is (Deep Thought from the Hitch Hikers Gide to the Galaxy by Douglas Adams).

Number 7 we can ignore (sorry Douglas Adams fans), although the real problem probably is that we do not understand the question. Number 6 is a chilling reminder of what can happen when ideology rules. For all the rest, the scientific method, as a method, is agnostic.

Contrary to popular opinion, the scientific method does not assume materialism, realism, or any other -ism. All one needs to carry out science are observations that can be used to construct and test models. Whether the observations are the result of a material world impinging on the mind through the senses, or purely illusions of the mind as in solipsism, does not really matter.  The relation between the models and reality is different for each of the options one through five, but observation cannot discriminate between them. At best, all observations can do is force ever more creative uses of the Duhem-Quine thesis. No matter how materialistic the universe may appear, there is always a place for God to hide; even if a being with vast knowledge and power showed up, there would be no way to prove he was God and not just a being from some highly advanced civilization.

Scientific models depend not just on observation, but also on simplicity—which is the only antidote to Duhem-Quine. Combining observation and simplicity, the current models of science tend strongly towards materialism. But this could change the next time science lurches in a new direction. Indeed, some claim that this has already happened with quantum mechanics. The measurement process in quantum mechanics is taken by some, possibly misguided souls, to indicate that consciousness has a vital role to play, hence tilting science towards idealism. Quantum mechanics and idealism may be no farther apart then classical mechanics and materialism.

While simplicity is an essential ingredient in constructing our scientific models, can we actually use it as a guide to reality, itself? Perhaps reality is not as simple as our models assume (note the word assume) and the world is only 6,000 thousand years old as Gosse suggested.  The lack of God or gods in our scientific models may be only a symptom of the failure of the simplicity assumption. The mind of God, if he exists, is unfathomable, so there is no guarantee that he would respect simplicity.

How do the models of science relate to the ultimate reality? That is unknown and unknowable. In classical mechanics, the particle trajectories and three-dimensional Euclidean geometry were assumed to be real. The first was destroyed by quantum mechanics, the second by relativity. There is no reason to assume the underpinnings and constructs of any current model will not be similarly undermined by future paradigm shifts. Independent of all that, our models stand, giving us the only useful knowledge available for how the universe works. Niels Bohr stated, “It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature.” As for the ultimate nature of reality, we find that in a song by Iris DeMent, Let the Mystery Be:

but no one knows for certain
and so it’s all the same to me
I think I’ll just let the mystery be

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The last day of Tevatron

Friday, September 30th, 2011

Today, September 30th, is the last day of operations of the largest US particle accelerator, the venerable Tevatron. Form many years it defined the American (and world’s) program in high energy particle physics. It saw its share of discoveries and trained a  ton of graduate students. For a theorist, Tevatron has continuously been a source of new data to explain or a machine that can confirm or rule out a model. What are the most significant papers that came out of the Tevatron?

In order to answer this question, let us use a tool that every theorist has in its disposal: SLAC SPIRES database. To be exact, we’ll use its modern incarnation, the INSPIRE. A quick search reveals that the most influential paper that came out of Tevatron (and the forth most influential that came out of Fermilab) is “Observation of top quark production in pˉp collisions” by  the CDF Collaboration, closely followed by a similar paper “Observation of the top quark” from the DO collaboration. Those papers from the two biggest Tevatron experiments describe the discovery of the sixth quark, the heaviest known so far — and probably the heaviest we shall ever see!

What is more striking is that while Tevatron was built to explore the “energy frontier“, i.e. to directly observe New Physics particles, the most influential papers that came out of CDF and D0 collaborations have to do with flavor physics (see also my recent colloquium)! In particular, papers on top quark discovery, discovery and precision measurements of of Bs-meson oscillations (see CDF and D0 papers),  measurements of J/psi (a bound state of charm and anti-charm quars) and b-quark production cross sections were sited by hundreds of researchers worldwide. Many of those analyses — as well as others, e.g. related to precision measurements of properties of W-bosons — greatly influenced indirect searches for physics beyond the Standard Model. I use those results routinely in my work! So maybe the decision to move Fermilab towards “intensity frontier” (i.e. careful precision studies of particle processes at lower energies to catch a glimpse of virtual New Physics particles) is the wise move based on the legacy of Tevatron.

 

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Sitting in the CDF collaboration meeting, discussing new and exciting results, while awaiting the end of the Tevatron in only a few hours...

Hello from Fermilab!

Today is a bittersweet day. As you have read in several posts here on the US LHC blog in Quantum Diaries, most recently from Kathy Copic, Michael Schmitt, and Ken Bloom, the Fermilab Tevatron, which for decades held the title of the “Highest Energy Accelerator in the World” (until the LHC began operations in 2009 of course), is ending its historic 28 year run.

This news has also made it into the popular press, such as the BBC, the Chicago Tribune (which discusses the future of Fermilab in brief as well) and the Washington Post, amongst many other publications and blogs.

Milestones?  Yes, there were many!  And while many of us are now working on the CMS and Atlas experiments in particular at the LHC, those of us who also remain on the Tevatron experiments (CDF and D0) are still working and producing results, and we are excited about the measurements we will publish with the final Tevatron datasets.

Robert Craig Group outlines plans for CDF's "final word" on the global search for the Higgs Boson.

Both D0 and CDF are holding collaboration meetings this week ahead of today’s shutdown.  Many current and former collaborators at our two experiments have traveled here from all over the world, even from CERN, to honor the end of an era of tremendous physics productivity and groundbreaking science here in the Chicago suburbs.

I am sitting here in the CDF collaboration meeting, discussing current and future physics results from CDF with my colleagues, while also discussing such topics as future data preservation (so we can access the data to study in the future as needed), and future tours of CDF and its detector as part of Fermilab’s proud legacy.  It is a pretty surreal feeling, to be pushing for exciting results in the next year while discussing the laying-to-rest of a beloved experiment.

Meanwhile, some of our former CDF colleagues, many of whom are now stationed part-time or full-time at CERN, are feeling wistful as well.  They have gathered together as many of our former ranks as they could find in a short period, and sent a send-off photo from all of them at CERN.

Former CDF colleagues gather at CERN for a farewell photo, sending best wishes as the Tevatron prepare to end operations today. (Photo courtesy of Michael Hoch)

One of my colleagues at CMS, Petra Merkel, who I used to work closely with here at CDF, sent the following thoughts along with the above photo:

“I must say that for most of us CDF has always played a special role, even if we have moved on to other experiments. But still now we frequently dwell upon the font memories we all have of our time at Fermilab, and of the very special atmosphere, which was present in CDF! Good luck to all of you, enjoy the party, and hope to see you soon, maybe at CERN.”

We will begin the shutdown ceremony today at 1:45, Chicago daylight time.  If you want to tune in to live video, the link is here. The schedule of events is exciting, but ceremonial compared to the feelings we all have on this day.

At CDF we will gather for a photo, then watch together the shutdown of the Tevatron in the CDF control room by video.  This will be followed by a champagne toast, and some testimonials from those who were around “in the beginning”.  Then CDF, D0, the Accelerator Division, and the whole lab plan to gather in the Fermilab Wilson Hall atrium to celebrate the end of the Tevatron era.  Both CDF and D0 plan further collaboration festivities into the evening, including an appearance by the CDF band.

To the end of an era and the beginning of a new one:  Here’s to continued exciting results from the Tevatron, and the wonderful results to come in the new LHC era…. Cheers!

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Tevatronic Rhapsody

Friday, September 30th, 2011

The big news today is that one of the biggest accelerators is shutting down after 28 years of excellent service. When SLAC closed down PEP-II, I wrote a tribute to the tune of American Pie (called “The Day the Mesons Died”) so it’s only fair that I do the same for Tevatron.

Although most of the time, Tevatron was an accelerator that always happened to be on the wrong side of the continent or the wrong side of the Atlantic, I did start my particle physics career with the help of CDF. I worked on Monte Carlo simulations, trying to find a strategy for measuring Bs oscillations. That’s where it all began, and for that I’m grateful.

So here we are, Tevatronic Rhapsody, (hastily written in the gaps between work) to the tune of Queen’s Bohemian Rhapsody. If you really want to annoy your office mates, you can sing along with this backing track.

Tevatronic Rhapsody

Is this the data?
Is this Monte Carlo?
Caught in a meeting
No escape from the next slideshow
Open your eyes
Look up to the slides and see
Is that the top quark?
Is it the final piece?
Because it’s rarely come
Quickly go
Mass is high
Lifetime low
Any way it decays doesn’t really matter to me
(\ell b)

Bs just flipped it quarks
Put an s where there was b
Now it violates CP
Bs, you were too heavy
But not for D0 and CDF!
Bs, ooooh
You decayed into hadrons
And showed us how to violate CP
With a phase, complex phase
Because antimatter matters

Too late, our time has come
No funding for the beams
No more events to be seen
Goodbye antiprotons
We’ve got to go
Got to analyze the data for results

Bs, oooh (any way the fit goes)
You went to two muons
More often than in the Standard Model
[Celebratory guitar riff]

I see a little silhouette-o of a peak
Is it Higgs? Is it Higgs?!
Will we get a Nobel Prize?
ICHEP, Lepton-Photon,
Conferences they go on

Set the limits! (Set the limits!) Set the limits! (Set the limits!) Set the limits! Make a plot!
Upload the taaaaalk!

Here is a spectrum, with strange topology
It is a dijet, it’s an anomaly!
Technicolor, or a monstrosity?

Heavy top, lighter top, is it CPT?
CPT? No! It violates Lorentz!
CPT?
CPT? No! It violates Lorentz!
CPT?
CPT? No! It violates Lorentz!
Violates Lorentz!
(CPT?)
Violates Lorentz!
(CPT?)
Violates Lorentz-enz-enz-enz!

Oh bottom mesons, and charmed mesons, and baryons, we saw them!
The quark model had positions set aside for all, (except the X!)

So you think you can stop us and turn off our beams?
So you think we won’t be publishing reams?
Oh, data
We’ve still got loads of data!
Just gotta publish
Just gotta analyze data

[Time to rock out]

The universe, it matters, anyone can see
More than antimatters, to me

Have a great Friday! And congratulations to everyone who worked with Tevatron. Today is the end of a glorious era and A Job Well Done (as we Brits say).

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the transatlantic shot setup

Friday, September 30th, 2011


As many others have posted, today is the day that the Fermilab Tevatron collider will end its 28-year career. (See the front page of Quantum Diaries for many more details!) It’s important to understand that Fermilab itself is not shutting down – there are other projects still taking place there. The Tevatron has been a huge part of Fermilab’s scientific program over the last few decades, though, and we should celebrate all its successes!

I did my Ph.D. research with the CDF Collaboration at Fermilab, using data delivered by the Tevatron. I even lived on the lab site for two years, in “the Michigan house,” which was a house full of Michigan graduate students. One thing I remember fondly about living at the lab was playing softball there (on the site! – go Springfield Isotopes!) and having after-game BBQ’s at our house.

I’m sad to be missing what promises to be a great farewell BBQ for the Tevatron at Fermilab tomorrow, but people everywhere will be raising a toast as they send around the last beams. I have an email in my inbox from friends at CERN, many of whom did their Ph.D. research at Fermilab like I did, having a farewell party tonight. They’ve even invented a signature cocktail, called the Transatlantic Shot Setup. I’ll be toasting with my family in sunny Florida, where we’re all together for my cousin’s wedding.

To explain how “shot setup” is related to Fermilab, I found this quote from an interview with Duke professor (and CDF and ATLAS collaborator) Mark Kruse.

Interviewer: What does doing your research look like?

MARK: So in the control room, things are most active during so-called “shot setup.” So “shot setup” is when the Tevatron has accumulated bunches of protons and anti-protons, injects them into the Tevatron accelerator, starts to accelerate them in opposite directions. And during that time, you’ve got to do various things to the proton/anti-proton beam. But as soon as the beams are stable and of good quality and they start colliding, then we have to be there at that instant in order to determine okay, things are running really well now. And of course during those first instances during “shot setup” and during data collection, it’s those first few minutes in essence that we have to keep a very close eye on how the detectors are performing.

For everyone that has spent time in the CDF or D0 control rooms and everyone who would have liked to, I give you:

=== The Transatlantic Shot Setup ===
A signature Tevatron shutdown cocktail
courtesy of Corrinne Mills (fellow blogger and fellow former Springfield Isotope) et al.

3 parts bourbon
1 part green Chartreuse
1 generous part lemon juice
0.5 parts simple syrup or to taste

Shake in a cocktail shaker and pour into glasses. Top with seltzer/sparkling water. For a non-transatlantic shot setup, you can leave out the French Chartreuse and stick with the American bourbon.

Cheers!

P.S. – Want to watch the events at Fermilab today? From 2 pm Central time, you can watch the broadcast online!

P.P.S – Here you can see some of the transatlantic celebrators from the CDF collaboration — all at CERN now!

 

 

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Yesterday we at Northwestern enjoyed a site visit by the DOE. The point of a site visit is to allow the DOE representative to assess, first hand, what the researchers are actually doing. Many senior physicists in HEP can write wonderful prose extolling the achievements of their groups, but a face-to-face meeting stretching over several hours allows the DOE representative to probe and check.

Anyway, one of the pleasures of the site visit is hearing what other researchers in your own institution have accomplished. There was one very brief presentation concerning the D0 experiment at the Tevatron, during which the speaker trotted out some of the nicest D0 results in electroweak and top physics. Since I am working hard in electroweak physics in CMS, and used to work in electroweak physics in CDF, I tend to view such presentations with a very critical eye. But indeed, setting aside any quibbles about systematic uncertainties and acceptance corrections, the achievements of the D0 Collaboration – and of the CDF Collaboration – are astounding considering the starting point back in the 1980s when I was still a graduate student. As Ken Bloom nicely explained, the physics results produced by D0 and CDF over a decade of 2 TeV running are far beyond anyone’s expectations, back in the 1980s. For example, the possibility of measuring of the top quark with an error better than 1.5 GeV was ridiculed at the start of Run II – yet look how well the Tevatron experiments have done and how important this result is for particle physics. Look at the measurement of the W mass, of Bs mixing and heavy flavor spectroscopy, of a wide range of QCD tests and studies of weak boson production, etc. etc. These results are like stars in the constellation of collider physics.

Two or three generations of Tevatron experimenters achieved what no one would have expected – projections for such measurements would have been considered pipe dreams, pie in the sky, or fantasy. Yet they did it, providing an excellent starting point for the LHC.

During the dinner that concludes the DOE site visit, we discussed prospects for measuring longitudinal WW scattering, which is intimately related to the existence and properties of a Higgs boson. The common wisdom is that it is very difficult and perhaps impossible to measure the cross section accurately. However, one or the theorists argued that, given time and data, experimenters always achieve more than one ever expects. I think he is right – and the record of the Tevatron proves it.

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When the proton becomes larger

Thursday, September 29th, 2011

The TOTEM experiment at the LHC has just confirmed that, at high energy, protons behave as if they were becoming larger. In more technical terms, their total cross-section – a parameter linked to the proton-proton interaction probability – increases with energy. This phenomenon, expected from previous measurements performed at much lower energy, has now been confirmed for the first time at the LHC’s unprecedented energy.

A composite particle like the proton is a complex system that in no way resembles a static Lego construction: sub-components move inside and interactions keep the whole thing together, but in a very dynamic way. This partly explains why even the very common proton can still be hiding secrets about its nature, decades after its discovery.

One way of studying the inner properties of the protons is to observe how they interact with each other, which, in technical terms, implies calculating the total cross-section of the proton-proton interactions. Early measurements at the CERN ISR surprisingly showed that the cross-section increases when the energy increases. This was then confirmed by the CERN SppS Collider and the Tevatron. But this is the first time that the trend has been confirmed at the highest energy, that of the LHC. “TOTEM’s result of (98 ± 3) mbarn for the total cross-section confirms that, even at the so far unexplored energy of the LHC, the proton behaves as if it were becoming larger”, says Karsten Eggert, spokesperson of the TOTEM collaboration.

Measuring the proton-proton total cross-section is not a trivial exercise. “We requested a special run of the LHC”, explains Eggert. “The beam divergence in the proximity of the interaction points in the machine had to be much smaller than in standard LHC operation. In only thirty minutes of data taking with this special beam configuration TOTEM collected sufficient data to measure the elastic proton-proton scattering cross-section, which ,made it possible to determine the total cross-section by using the so-called optical theorem” .

From the CERN Bulletin

TOTEM measurement of the total cross-section of the proton at the 7 TeV centre-of-mass energy

shown in red, in perfect agreement with extrapolation from lower energy measurements.

 

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Quand le proton se fait plus grand

Thursday, September 29th, 2011

L’expérience TOTEM du LHC vient de confirmer que, à de hautes énergies, les protons se comportent comme s’ils devenaient plus grands. En termes plus techniques, leur section efficace totale (paramètre lié à la probabilité d’interaction proton-proton) augmente avec l’énergie. Ce phénomène, que des mesures réalisées à des énergies beaucoup plus basses laissaient entrevoir, a été confirmé pour la première fois grâce aux énergies générées par le LHC et jamais atteintes auparavant.

Une particule composite comme le proton est un système complexe qui ne ressemble en rien à une construction statique telle qu’un Lego : des sous-éléments se déplacent à l’intérieur du système et des interactions permettent d’en conserver l’unité, tout cela de manière très dynamique. C’est cette structure qui explique, en partie, pourquoi même le proton, cette particule très commune, peut encore receler des secrets sur sa nature, des décennies après sa découverte.

Pour étudier les propriétés internes des protons, l’une des méthodes possibles consiste à observer la façon dont ils interagissent entre eux. En termes techniques, on cherche à calculer la section efficace totale des interactions proton-proton. Des mesures effectuées précédemment aux ISR du CERN avaient révélé que, de manière surprenante, la section efficace augmentait lorsque les énergies étaient plus hautes. Le collisionneur SppS du CERN et le Tevatron ont ensuite fait la même observation. C’est en revanche la première fois que cette tendance est confirmée aux plus hautes énergies, celles du LHC. « Les résultats de (98 ± 3) mbarn pour la section efficace totale, obtenus par l’expérience TOTEM, confirment que, même aux énergies très élevées du LHC, les protons se comportent comme s’il devenaient plus grands », explique Karsten Eggert, porte-parole de la collaboration TOTEM.

La mesure de la section efficace totale n’est pas une mince affaire. « Nous avons demandé une exploitation spéciale du LHC, poursuit Karsten Eggert. La divergence des faisceaux à proximité des points d’interaction devait être beaucoup plus petite que pour une exploitation standard du LHC. En seulement trente minutes de prise de données avec cette configuration de faisceau particulière, TOTEM a pu recueillir suffisamment d’informations pour mesurer la section efficace de diffusion élastique proton-proton, ce qui nous a permis de déterminer la section efficace totale en appliquant ce qu’on appelle le théorème optique. »

Le mode de calcul actuel s’appuie sur les mesures de luminosité effectuées par l’expérience CMS, mais dans ses programmes futurs, la collaboration TOTEM souhaiterait utiliser uniquement ses propres détecteurs afin d’obtenir une mesure indépendante de la luminosité. « Dans un avenir assez proche, nous allons bénéficier d’une exploitation spéciale du LHC de plus longue durée et pourrons rapprocher nos détecteurs des faisceaux », ajoute Karsten Eggert.

Les récents résultats de l’expérience TOTEM apporteront une contribution importante à notre connaissance de la nature des protons. D’après la théorie, nous savons qu’il existe une limite de taille que les protons peuvent atteindre aux plus hautes énergies. « À l’heure actuelle, nos résultats concordent parfaitement avec les données issues des rayons cosmiques et les extrapolations faites à partir des mesures précédentes. Ces résultats constituent la première confirmation expérimentale de certaines hypothèses émises de longue date au sujet du comportement du proton à de hautes énergies », conclut Karsten Eggert.

Tiré du Bulletin du CERN

Mesure de TOTEM de la section efficace totale du proton à une énergie dans le centre de masse de 

7 TeV en accord parfait avec l’extrapolation des mesures faites à plus faible énergie.

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Tevatron past as LHC prologue

Wednesday, September 28th, 2011

This Friday, Fermilab will turn off the Tevatron for the last time after a 28-year run. It has been a constant in my life as a particle physicist, and indeed for a whole generation of particle physicists. I know some people who have managed to spend their entire careers involved with the Tevatron in some way. Not true for me; I was on hiatus at the Cornell Electron Storage Ring for five years as a graduate student. But the Tevatron was where I had my first experiences as an undergraduate researcher; as a college freshman, I was stunned to find myself with a Fermilab ID card in my pocket and suddenly in on the hunt for the top quark. (No dice; another six years, significant detector upgrades, and more than an order of magnitude more data had to come first.) And as a postdoctoral researcher, it was where I had my greatest triumphs (moderate as they may be) as a full-time researcher. (As a professor with many other things to juggle, it would be a stretch to call me a full-time researcher now.) I learned a tremendous amount along the way about physics and about how to be a physicist.

(But I will not be attending the shutdown ceremonies on September 30 — it’s Rosh Hashanah, the Jewish new year. What is it with the managers of particle physics laboratories who can’t read a calendar? So much for getting Fermilab Today to pick up this blog post….)

The Tevatron’s longevity surely puts it into a special category of scientific enterprises that have captured the public imagination because of their epic scope. The Voyager 1 satellite, for instance, has been chugging along since 1979, and barring unforeseen circumstances will continue to tell us about the nature of the universe. The Tevatron in its own way will keep chugging along too, as there is so much data yet to analyze that it will keep teaching us about the universe for some years to come.

I’m not going to tick off all of the accomplishments of the Tevatron and CDF and D0, its principal experiments; this has been done elsewhere, and also has been covered in excellent presentations at the DPF meeting by Steve Holmes and Paul Grannis, both of whom were there pretty much from the beginning. (Chris Quigg also provides a lovely summary of the physics achievements in the CERN Courier.) But what I would like to point out is that the Tevatron program of 2011 is not the program that was envisioned when the machine design was launched in the late 1970’s. The clear targets of the machine were the W and Z bosons and the top quark, and these are now understood in detail because of the Tevatron. But as far as I know, no one anticipated the program of bottom-quark physics that emerged, no one thought that precision measurements of masses could be done at a hadron collider, and even just a few years ago it would have been optimistic to suggest that the Tevatron experiments would have the capability to observe the Higgs boson. On the accelerator side, the final instantaneous luminosity was a factor of 400 better than design, meaning that there was an average 35% annual improvement over twenty years.

Since this is an LHC blog — what can we learn about the LHC from this? It is that we should not underestimate the potential that we have in front of us. The LHC will likely operate for as long as the Tevatron has, and we can realistically expect similar performance improvements along the way. We should also not underestimate how our experimental reach can be increased through advances in detector technology, and the just plain cleverness that physicists will bring to the table when given the chance to solve a challenging and important problem. In 2037, there will be new generation of particle physicists for whom the LHC is a constant of life, and I expect that we will be looking back on an LHC legacy that is just as memorable as that of the Tevatron.

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Fermilab’s Tevatron Shutdown Event

Wednesday, September 28th, 2011

So this Friday is the shutdown of Fermilab’s Proton/Anti-Proton Collider the Tevatron. After almost 30 years of service and numerous discoveries the collider has run her course and is scheduled to be turned off.

Instead of this being a sad event Fermilab is going to let the old girl go out with a bang! A celebration is planned and I hope to be able to blog about it and bring pictures and thoughts about the days activities.

CDF has their experiments collaboration meeting going on over the next few days (at which I am giving a talk on my own analysis) and then a big celebration planned on Friday when they finally shut down the detector and the accelerator.

Live streaming media from both the Main Control room as well as CDF and D0 control rooms will be provided by Fermilab Visual Media Services.

Additionally, Chicago’s own National Public Radio WBEZ did a show about the Tevatron that can be found here

The festivities and physics to come are sure to be exciting. So instead of being sad about the end of one of the most ground breaking experiments in science…here is a picture of a Corgi in a swing….adorable!

 

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