Tag archives: particle accelerator
By Tushna Commissariat
After months of rumours, speculation and some 500 papers posted to the arXiv in an attempt to explain it, the ATLAS and CMS collaborations have confirmed that the small excess of diphoton events, or “bump”, at 750 GeV detected in their preliminary data is a mere statistical fluctuation that has disappeared in the light of more data. Most folks in the particle-physics community will have been unsurprised if a bit disappointed by today’s announcement at the International Conference on High Energy Physics (ICHEP) 2016, currently taking place in Chicago.
The story began around this time last year, soon after the LHC was rebooted and began its impressive 13 TeV run, when the ATLAS collaboration saw more events than expected around the 750 GeV mass window. This bump immediately caught the interest of physicists the world over, simply because there was a sniff of “new physics” around it, meaning that the Standard Model of particle physics did not predict the existence of a particle at that energy. But also, it was the first interesting data to emerge from the LHC after its momentous discovery of the Higgs boson in 2012 and if it had held, would have been one of the most exciting discoveries in modern particle physics.
By Tushna Commissariat
If you have never been one of the lucky few to have wandered the tunnels of a particle accelerator, but have always wondered what lies within, take a look at the video above. The European X-ray Free Electron Laser (European XFEL) – which is currently under construction in Germany and will come online next year – will provide ultrashort (27,000 X-ray flashes per second) and ultrabright X-ray laser flashes that are needed to study chemical reactions in situ or to study extreme states of matter (you can read more about the kind of research that will be done there in the September issue of Physics World magazine). The XFEL tunnel is 3.4 km long and you can zoom across all of it in the 5 minute long video. I particularly enjoyed watching particular locations where engineers could be seen carrying out tests, as well as watching folks on bicycles wobble out of the camera’s way.
On a slightly related note, if, like me, you occasionally get a bit muddled when it comes to certain details of different particle accelerators – for example which came first, the synchrotron or the cyclotron – take a look at this excellent “primer” over at Symmetry magazine.
By Matin Durrani in Beijing, China
I had just landed in Beijing this morning when I saw an e-mail from my colleague Mingfang Lu waiting for me on my phone. Mingfang, who’s editor-in-chief at the Beijing office of the Institute of Physics, which publishes Physics World, has been helping me to organize my itinerary for the next week as I gather material for our upcoming special report on physics in China. You may remember we published a Physics World special report on China in 2011 but so much has happened since then that we felt it’s easily time for another.
Mingfang’s e-mail was to say we would be off at 2.30 p.m. to interview Xinchou Lou, a particle physicist at the Institute of High Energy Physics, about the country’s ambitious plans for a “Higgs factory”. If built, this 240 GeV Circular Electron–Positron Collider (CEPC) would be a huge facility (50 km or possibly even 100 km in circumference) that will let physicists study the properties of the Higgs boson in detail. I say “if”, but knowing China’s frenetic progress in physics, it will almost certainly be a case of “when”.
By Hamish Johnston at the APS April Meeting in Salt Lake City
This morning Mei Bai of the Jülich Institute for Nuclear Physics in Germany used a lovely phrase during her talk at the APS April Meeting. She showed a slide called the “accelerator tree”‘, which refers to a paper by Ugo Amaldi called “The importance of particle accelerators“.
By Tushna Commissariat in New York City, US
I’m not one to rejoice in someone else’s misfortune, but I must admit that I couldn’t help but be a bit pleased when I heard that the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory (BNL) had a malfunction last Friday. You see, I happened to be visiting the collider and its detectors yesterday, and if a malfunctioning superconducting magnet had not shorted a diode last Friday, I would not have had the chance to go down into the collider tunnel, which was a great experience.
RHIC – which, along with the Large Hadron Collider at CERN, is the only other detector capable of colliding heavy ions and is, in fact, the only spin-polarized collider in the world – has been running since the year 2000, and accelerator director Wolfram Fischer tells me that I am rather “lucky” as “failed magnets are very rare”. Indeed, he said that after initial teething problems when RHIC was switched on, this was the first such magnet failure that has occurred in the past 15 years. But fear not, the RHIC maintenance crew is already hard at work – the diode will soon be replaced and the collider should be up and running again in the next few days.
By Tushna Commissariat
I’m sure that many of us, while watching videos of astronauts on board the International Space Station (ISS), floating around with their halo-like hair, have given much thought to how they shower, wash their hair, brush their teeth and, indeed, poop and pee! Well, you can stop stretching your imagination and take a look for yourself – we spotted this story on the Slate website, where you can see the latest videos from the European Space agency, where Italian astronaut Samantha Cristoforetti, who is currently on the ISS, gives us a tour of both the toilet (above) and the “shower” area (below). She even demonstrates exactly how to wash your hair in space – it looks rather fuss-free if you ask me!
By Hamish Johnston and Tushna Commissariat
As it’s Good Friday today, it can only mean that this week’s Red Folder will include a selection of the best physics-related April Fool jokes from earlier this week. Fermilab’s daily e-bulletin Fermilab Today had an entire joke edition up in the morning – their lead story was probably our favourite as the lab announced its new breakfast cereal dubbed “Neutrin-Os”, but their new day spa sounds pretty good too. CERN went for the funny if slightly obvious Star Wars joke, confirming the existence of the Force, but a slightly more subtle joke came earlier in the week from CERN Bulletin, which ran a story about CERN’s computer-security department handing out prizes for best password – we are still not quite sure if they were joking or not! Astronomy Picture of the Day had a truly fantastic image (see above) of a Lunar Grazing Module described as a “multipurpose celestial bovine containment system”.
By Tushna Commissariat at CERN
Regular readers of Physics World will know that I am currently visiting the CERN particle physics lab in Geneva, ahead of the restart of the Large Hadron Collider (LHC) in the coming weeks. My first stop yesterday afternoon was a press conference in which CERN’s director-general Rolf Heuer and other leading physicists briefed us about “Run 2” and what researchers are hoping to discover. You can read about what they had to say here: “Large Hadron Collider fires up in a bid to overturn the Standard Model“.
I managed to squeeze in a quick last-minute visit to the Compact Muon Solenoid (CMS) detector before it is sealed up tight for the next three years. My host was CMS communications officer Achintya Rao, who took me and a few others deep underground into the bowels of the CMS – and what a sight it was!
By Tushna Commissariat
This week, we came across the above video on “extra dimensions”, in which physicist Don Lincoln talks about the possible physical reality of such dimensions and why we need them. The video begins with Lincoln pointing out just how weak a force gravity is, especially when compared with, say, magnetism. He then goes on to talk about how gravity may exist in more than the three dimensions we experience, making sure to point out that these “extra dimensions” are not of the Hollywood variety in which a different reality may exist. This video is part of Fermilab’s “Big Mysteries” video series – be sure to take a look at the rest.
By Hamish Johnston
In the 25th anniversary issue of Physics World, I made the bold assertion that laser acceleration will bring particle therapy to the masses by removing the need for treatment centres to have large and expensive accelerators. Instead, therapeutic beams of protons and other charged particles will be made using compact and relatively inexpensive lasers.
Now, medical physicist Umar Masood and colleagues at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the University of Dresden have published plans for a laser-driven proton-therapy facility.