MIT Cyclotron magnet (Building 44)
The cyclotron was the first circular particle accelerator design, developed by Ernest Lawrence at Berkeley in the early 30s. Particles started out in the center of the big magnet and were accelerated by an oscillating electric field. The magnetic field from the big magnet causes the accelerated particles to bend in a circle, going in wider circles as they get accelerated. When they reach maximum energy they are extracted to hit a target in the next room.
After Lawrence invented the idea, lots of universities built them. This one dates to about 1940. All that remained of the cyclotron was the big magnet. I think this magnet was capable of a field of about 1 T, maybe 1.5 T. That’s from memory. Unfortunately I can’t find any detailed information about it on the web.
This building was torn down just a couple years ago, in 2020 or so.
At the time this photo was taken, Prof Becker had a small drift chamber that he had built installed in the center of the magnet. (A drift chamber is a type of particle detector in which the passage of a charged particle ionizes a gas in the chamber. The ionization drifts in an electric field to one end of the chamber where it is detected by wires held at a high voltage.) Over the years he used this setup to do experiments on the ionization and electron drift properties of various gas mixtures, with applications to full-sized detectors.
In the green paint on the top part of the magnet yoke you’ll notice the ghost letters “SS”. I think this is the remnants of “SSC” for Superconducting Supercollider, the effort that would have put an energy-frontier proton collider in Texas and beat the LHC to the Higgs boson discovery by 10 years, but was canceled by Congress early in the Clinton administration.
You will notice the glass vessel filled with water in the foreground. Prof Becker had asked me to do a side project that involved measuring a volume of gas, which I was doing by measuring the displacement of the water in the graduated cylinder. My memory is fuzzy but I believe that this was a small R&D test for a component of the AMS02 experiment that was being designed for the International Space Station. You can see that the gas is connected to a small object in the magnet that is then connected to my water setup. I think that small object was a little electromechanical valve, and I was testing its performance in a strong magnetic field. AMS02 was going to have a strong magnet and a gas-based detector (I can't remember for sure but maybe the TRD: ams02.space/detector/transition-radiation-detector-trd ), so this makes some sense. AMS02 finally got off the ground to the International Space Station in 2011 (and probably never would have gotten that far without Sam Ting’s political clout).
Speaking of Sam Ting, this building was his fiefdom. He won the Nobel Prize for the discovery of the J/Psi particle (and thus the charm quark) in 1974. Ting’s group (including Prof Becker) were collecting data at Brookhaven National Lab in New York. Legend has it that they saw a peak in their data but delayed publishing to be absolutely sure of their results. In the meantime a group at SLAC led by Burt Richter saw a peak in electron-positron collisions. In the end, the 2 groups published on the same day in 1974, meaning that credit had to be shared. Ting named the new particle “J”, which looked similar to a Chinese character in his name. The SLAC team gave the name psi. The community settled on using “J/Psi” going forward. Ting had a giant sign with the letter J installed over the entrance to this building ( www.flickr.com/photos/bmeeee/17011649352/ ). Prof Becker kept his punch cards from the original data analysis in a locked cabinet in the building.
Back in the day I heard a story where the spin was that Becker was confident in the discovery but Ting was conservative, and this conservatism led to the publishing delay that cost the MIT team primacy in the discovery over the SLAC team. The legend speculated that a sole discovery by the MIT team would have led to Ting and Becker winning the Nobel Prize together, while in reality the shared discovery with SLAC meant that the prize had to be shared by the groups. Since Ting and Richter were the group leaders, the prize was shared by them, leaving Becker in the lurch. This story is confirmed somewhat in this article published after Prof Becker's death in 2020: news.mit.edu/2020/ulrich-becker-mit-professor-emeritus-ph... (This article also contains a wonderful anecdote that Prof Becker told me personally once, about an encounter with the aging Werner Heisenberg after the discovery of the J/Psi.)
There were accompanying legends that there was a leak of information from the MIT team to SLAC, facilitating them to search at the right energy. This history by Richter certainly doesn’t say that: www.slac.stanford.edu/history/pubs/richterdis.pdf (it's quite amazing that they made the discovery one day and submitted the results for publication the next day) but the MIT News article above does paint a timeline where the Brookhaven results were being discussed privately for quite a while before the SLAC discovery.
By coincidence I went from being an undergrad in Building 44, learning from Prof Becker, to being a graduate student at SLAC working in Group C, which had previously been led by Richter and was then led by Vera Luth who was a junior member on Richter’s team at the time of the J/Psi discovery.
MIT Cyclotron magnet (Building 44)
The cyclotron was the first circular particle accelerator design, developed by Ernest Lawrence at Berkeley in the early 30s. Particles started out in the center of the big magnet and were accelerated by an oscillating electric field. The magnetic field from the big magnet causes the accelerated particles to bend in a circle, going in wider circles as they get accelerated. When they reach maximum energy they are extracted to hit a target in the next room.
After Lawrence invented the idea, lots of universities built them. This one dates to about 1940. All that remained of the cyclotron was the big magnet. I think this magnet was capable of a field of about 1 T, maybe 1.5 T. That’s from memory. Unfortunately I can’t find any detailed information about it on the web.
This building was torn down just a couple years ago, in 2020 or so.
At the time this photo was taken, Prof Becker had a small drift chamber that he had built installed in the center of the magnet. (A drift chamber is a type of particle detector in which the passage of a charged particle ionizes a gas in the chamber. The ionization drifts in an electric field to one end of the chamber where it is detected by wires held at a high voltage.) Over the years he used this setup to do experiments on the ionization and electron drift properties of various gas mixtures, with applications to full-sized detectors.
In the green paint on the top part of the magnet yoke you’ll notice the ghost letters “SS”. I think this is the remnants of “SSC” for Superconducting Supercollider, the effort that would have put an energy-frontier proton collider in Texas and beat the LHC to the Higgs boson discovery by 10 years, but was canceled by Congress early in the Clinton administration.
You will notice the glass vessel filled with water in the foreground. Prof Becker had asked me to do a side project that involved measuring a volume of gas, which I was doing by measuring the displacement of the water in the graduated cylinder. My memory is fuzzy but I believe that this was a small R&D test for a component of the AMS02 experiment that was being designed for the International Space Station. You can see that the gas is connected to a small object in the magnet that is then connected to my water setup. I think that small object was a little electromechanical valve, and I was testing its performance in a strong magnetic field. AMS02 was going to have a strong magnet and a gas-based detector (I can't remember for sure but maybe the TRD: ams02.space/detector/transition-radiation-detector-trd ), so this makes some sense. AMS02 finally got off the ground to the International Space Station in 2011 (and probably never would have gotten that far without Sam Ting’s political clout).
Speaking of Sam Ting, this building was his fiefdom. He won the Nobel Prize for the discovery of the J/Psi particle (and thus the charm quark) in 1974. Ting’s group (including Prof Becker) were collecting data at Brookhaven National Lab in New York. Legend has it that they saw a peak in their data but delayed publishing to be absolutely sure of their results. In the meantime a group at SLAC led by Burt Richter saw a peak in electron-positron collisions. In the end, the 2 groups published on the same day in 1974, meaning that credit had to be shared. Ting named the new particle “J”, which looked similar to a Chinese character in his name. The SLAC team gave the name psi. The community settled on using “J/Psi” going forward. Ting had a giant sign with the letter J installed over the entrance to this building ( www.flickr.com/photos/bmeeee/17011649352/ ). Prof Becker kept his punch cards from the original data analysis in a locked cabinet in the building.
Back in the day I heard a story where the spin was that Becker was confident in the discovery but Ting was conservative, and this conservatism led to the publishing delay that cost the MIT team primacy in the discovery over the SLAC team. The legend speculated that a sole discovery by the MIT team would have led to Ting and Becker winning the Nobel Prize together, while in reality the shared discovery with SLAC meant that the prize had to be shared by the groups. Since Ting and Richter were the group leaders, the prize was shared by them, leaving Becker in the lurch. This story is confirmed somewhat in this article published after Prof Becker's death in 2020: news.mit.edu/2020/ulrich-becker-mit-professor-emeritus-ph... (This article also contains a wonderful anecdote that Prof Becker told me personally once, about an encounter with the aging Werner Heisenberg after the discovery of the J/Psi.)
There were accompanying legends that there was a leak of information from the MIT team to SLAC, facilitating them to search at the right energy. This history by Richter certainly doesn’t say that: www.slac.stanford.edu/history/pubs/richterdis.pdf (it's quite amazing that they made the discovery one day and submitted the results for publication the next day) but the MIT News article above does paint a timeline where the Brookhaven results were being discussed privately for quite a while before the SLAC discovery.
By coincidence I went from being an undergrad in Building 44, learning from Prof Becker, to being a graduate student at SLAC working in Group C, which had previously been led by Richter and was then led by Vera Luth who was a junior member on Richter’s team at the time of the J/Psi discovery.