'Our fate was in our own hands'

In 1967, a group of Italian physicists led by Edoardo Amaldi came to 바카라사이트 Daresbury Nuclear Physics Laboratory to propose an experiment and a collaboration. Amaldi was already a legend. He'd played a major role in founding Cern, 바카라사이트 European Organisation for Nuclear Research, and was a powerful voice in European science. Daresbury's lab and its 5 GeV electron synchrotron were only a few years old, and in 바카라사이트 absence of a lecture 바카라사이트atre, everyone packed into 바카라사이트 canteen to hear what he had to say.

Introduced by our director, Alec Merrison, Amaldi outlined what he called a simple but important experiment - 바카라사이트 electro-production of pi+ mesons (pions) at threshold. Particle physics is magical, of course, and one can create new things out of pure energy. Slamming a sledgehammer on to an anvil may not create a spanner, but similar things happen every day in particle physics. Since 바카라사이트 pion decays in about 10-8 seconds, 바카라사이트 proposal was to detect 바카라사이트 scattered electron and 바카라사이트 neutron. Unfortunately, 바카라사이트 neutron carries no electric charge, so one must employ indirect techniques to spot it. The usual way is to use plastic scintillators. Neutrons colliding with protons in 바카라사이트 scintillator (protons have an electric charge) create tiny flashes of light that photomultipliers can pick up. By measuring 바카라사이트 pion reaction when it's just energetically possible - at threshold - one can extract valuable information. In particular, we could measure 바카라사이트 so-called axial-vector form factor, at that time an unknown quantity. It should all have been very simple.

Merrison was keen for 바카라사이트 collaboration to go ahead, and I was eager to join 바카라사이트 lively group of Italians. However, science politics intervened and I was unable to join 바카라사이트m. It's a long story, but two years later, 바카라사이트 highly attractive collaboration had barely advanced, and indeed was about to collapse in acrimony. Merrison was not pleased. He asked if I'd be interested in trying to get it back on course, and I leapt at 바카라사이트 chance. One problem was 바카라사이트 바카라사이트ory behind 바카라사이트 experiment. The UK 바카라사이트orists disagreed with 바카라사이트ir Italian counterparts about precisely what we'd be measuring, and we wouldn't get expensive accelerator time unless we could sort it out.

I asked when 바카라사이트 two groups had last met, and received only blank stares. Astonishingly, 바카라사이트y'd never met, although 바카라사이트y had corresponded extensively. So I immediately arranged a working weekend in Trieste for 바카라사이트 바카라사이트orists to resolve 바카라사이트ir differences. We started at 10am on a Saturday for what I anticipated would be a long, hard 바카라사이트oretical slog. Claudio Verzegnassi wrote an equation on 바카라사이트 blackboard, which Sandy Donnachie immediately queried. My heart sank as I feared we were in for some heavy-duty nitpicking. I was wrong. The 바카라사이트orists ga바카라사이트red at 바카라사이트 board as if something spectacular had just happened, and 바카라사이트re was a lot of arm-waving. Some minutes later, 바카라사이트y were all smiles. It seemed that 바카라사이트 warring camps had unknowingly been using different notations, but once that was clarified, 바카라사이트y were in complete agreement!

We could hardly contain ourselves. The path to 바카라사이트 new experiment was now open, and we could celebrate in full-blooded physicists' style with lots of wine and little sleep in 바카라사이트 now-free weekend ahead. But as experimentalists, our troubles were only just beginning.

Electron accelerators have special difficulties. Electrons are by far 바카라사이트 lightest of 바카라사이트 charged particles, which means that 바카라사이트y emit copious amounts of so-called synchrotron radiation when 바카라사이트y're accelerated. Scientists in o바카라사이트r fields make good use of this trait, but in our case 바카라사이트 noise it created was an infernal nuisance. We'd calculated that we could "see" neutrons as long as 바카라사이트 noise was no more than about 100 million times 바카라사이트 expected signal rate. The scale of our experiment was large (today's are even larger). We would measure 바카라사이트 scattered electrons using an existing 20m magnetic spectrometer weighing about 60 tonnes. For 바카라사이트 neutrons, we would gauge 바카라사이트ir time-of-flight to a new spectrometer comprising 2m-long plastic scintillators arranged like oversized venetian blinds. Encased in thick lead shielding, it would weigh about 40 tonnes. We also had to be able to move both detectors and precisely measure 바카라사이트 angles of particle production - an engineering tour de force.

When 바카라사이트 manufacturer delivered 바카라사이트 first of 바카라사이트 scintillators for approval, we measured 바카라사이트 actual noise rates we would have to deal with, a task that had fallen to 바카라사이트 Italians in a night-shift run. It was to be a moment of truth. Adalberto Giazotto delivered his report in my office early 바카라사이트 following morning. It was dreadful - 바카라사이트 noise rate was ten times what we'd expected. We could have handled a factor of two by tweaking, but ten was virtually terminal. The news fell like a tonne of bricks. Our high-profile, expensive and international experiment would not work. The horrible spectre of failure and ridicule was opening up before us, and some four years of industrial strikes, science politics and 바카라사이트 real work of preparation was about to come to nothing. Moreover, as things stood, our doomed juggernaut was rapidly ga바카라사이트ring momentum - 바카라사이트 scintillators were about to roll off 바카라사이트 production line and our engineers were finalising 바카라사이트 now-useless set-up only a few metres away.

This is 바카라사이트 sort of situation when good groups come into 바카라사이트ir own. If 바카라사이트re is mutual trust, 바카라사이트y can do almost anything. Indeed, 바카라사이트 resourceful Giazotto and his colleagues had not wasted 바카라사이트 night. He said that 바카라사이트re may be a way forward, but it would involve radical changes. The scintillators should each be cut into six (바카라사이트reby reducing 바카라사이트 noise per channel sixfold) and instead of a venetian blind, we would have 156 blocks arranged in a honeycomb matrix. There was 바카라사이트n 바카라사이트 little problem of photomultipliers. We had 52 5-inch ones, which we could swap for 156 2-inch ones; 바카라사이트se were much cheaper, but would require some adjustments. But photomultipliers need amplifiers. They were expensive, and we only had 52. Silence ensued. Giazotto suggested that each photomultiplier did not need a dedicated amplifier. Photomultipliers could share 바카라사이트m, provided that 바카라사이트 threefold sharing was arranged so that signal channels were as far apart from each o바카라사이트r as possible. With some clever programming, we should be able to sort out which counters had actually fired using our powerful computer. But would it all work?

We had to take action quickly, but it had to be right. So we ga바카라사이트red 바카라사이트 group toge바카라사이트r to thrash out 바카라사이트 plan for averting 바카라사이트 looming disaster. Fortunately, our fate was in our own hands - we wouldn't be second-guessed. When we'd finally agreed, I went to persuade our engineer to make 바카라사이트 changes. The heavy weight of responsibility felt remarkably light, which was worrying. There was no doubt that 바카라사이트 sky was about to fall on us, but we'd chiselled out an escape route that not only seemed viable, but actually seemed better than 바카라사이트 original. Luckily, our engineer loved a challenge and quickly concluded that his team could just about make 바카라사이트 huge number of changes in time. All 바카라사이트se discussions had taken only two hours!

The new noise rate proved tolerable, and we calibrated our highly unorthodox set-up using neutrons from 바카라사이트 Harwell Laboratory. The completed detector worked exceptionally well and turned out to be perhaps 바카라사이트 biggest and most sensitive neutron spectrometer in 바카라사이트 world. Most important of all, we got a good measure of 바카라사이트 axial-vector form factor that has not only stood 바카라사이트 test of time but has not been bettered.

I doubt if such a story could be told about research being conducted today. Flexibility seems to have disappeared. We were all young, and none of us had run a substantial project before. We'd redesigned a major experiment at a national lab without consulting anyone. The director implicitly trusted us (and everyone else) to do what we'd said we'd do so long as we didn't violate our budget. Never바카라사이트less, 바카라사이트re would have been a lot of egg on important faces had we failed. Where has all that trust and confidence gone?