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CERN Courier – Digital Edition Welcome to the Digital Edition of the March/April 2021 Issue of CERN Courier CERNMarch/April 2021 cerncourier.com COURIERReporting on international high-energy physics WELCOME CERN Courier – digital edition Welcome to the digital edition of the March/April 2021 issue of CERN Courier. Hadron colliders have contributed to a golden era of discovery in high-energy physics, hosting experiments that have enabled physicists to unearth the cornerstones of the Standard Model. This success story began 50 years ago with CERN’s Intersecting Storage Rings (featured on the cover of this issue) and culminated in the Large Hadron Collider (p38) – which has spawned thousands of papers in its first 10 years of operations alone (p47). It also bodes well for a potential future circular collider at CERN operating at a centre-of-mass energy of at least 100 TeV, a feasibility study for which is now in full swing. Even hadron colliders have their limits, however. To explore possible new physics at the highest energy scales, physicists are mounting a series of experiments to search for very weakly interacting “slim” particles that arise from extensions in the Standard Model (p25). Also celebrating a golden anniversary this year is the Institute for Nuclear Research in Moscow (p33), while, elsewhere in this issue: quantum sensors HADRON COLLIDERS target gravitational waves (p10); X-rays go behind the scenes of supernova 50 years of discovery 1987A (p12); a high-performance computing collaboration forms to handle the big-physics data onslaught (p22); Steven Weinberg talks about his latest work (p51); and much more. To sign up to the new-issue alert, please visit: http://comms.iop.org/k/iop/cerncourier To subscribe to the magazine, please visit: https://cerncourier.com/p/about-cern-courier EDITOR: MATTHEW CHALMERS, CERN DIGITAL EDITION CREATED BY IOP PUBLISHING ATLAS spots rare Higgs decay Weinberg on effective field theory Hunting for WISPs CCMarApr21_Cover_v1.indd 1 12/02/2021 09:24 CERNCOURIER www. V OLUME 6 1 N UMBER 2 M ARCH / A PRIL 2 0 2 1 CERNCOURIER.COM Your DIGITAL POWER ELECTRONICS V OLUME 61 N UMBER 2 M ARCH /A PRIL 2 02 1 Partner IN THIS ISSUE It’s ALL ATLAS Baikal-GVD CERN about the DETAILS Dalitz decay ATLAS spots rare decay of the Higgs boson Universal search Baikal-GVD will continue the Staff search CER N’s efforts to attract to a photon and a low-mass electron or muon pair. 17 astrophysical neutrino search. 33 non-physicists into key roles. 61 NEWS PEOPLE ANALYSIS ENERGY FRONTIERS FIELD NOTES CAREERS OBITUARIES AEgIS on track to test First evidence for rare Tooling up to hunt dark Accelerating talent • Jack Steinberger antimatter free fall Higgs-boson decay matter • Computing at CERN • Martinus Veltman • NICA sees first beam • Supersymmetry collaboration kicks off The challenge of attracting • Günther Plass • CLOUD and Arctic sea searches • Precision • Quark-matter fireballs engineers, technicians • André Martin ice Quantum sensing leap for B0 Light shines in Protvino. 21 • s • and others who build and • Stephanie Zimmermann • Farewell Daya Bay inside lead nuclei. 17 maintain CERN’s complex • Stephen Reucroft • The core of SN1987A. 7 infrastructure. 61 • Jean-Claude Berset. 69 FEATURES WISPS Müller-Elsner DESY/Heiner INR RAS HADRON COLLIDERS LHC In search of WISPs Russia’s particle- Discovery machines A decade in LHC New experiments will physics powerhouse Lyn Evans and Peter publications expand the search for The Institute for Nuclear Jenni look at the lessons Alex Kohls, Jens Vigen axions and other weakly Research in Moscow learned from 50 years and Micha Moskovic interacting ‘slim’ particles continues to leave its of experience with look back on the that could hail from far mark on neutrino and hadron colliders and first 10 years of LHC above the TeV scale. 25 high-energy physics. 33 their detectors. 38 publications. 47 OPINION DEPARTMENTS VIEWPOINT INTERVIEW REVIEWS FROM THE EDITOR 5 Power Supply Systems CERN Connecting physics Still seeking The hitchhiker’s NEWS DIGEST 15 Precision Current Measurements with society solutions guide to weak decays APPOINTMENTS 62 We must communicate Steven Weinberg reflects An expedition to & AWARDS Beamline Electronic Instrumentation the applications and on effective field theory new physics summits RECRUITMENT 64 impact of our field, and his latest attempt to • The science of On the cover: CERN’s FMC and MicroTCA argues Barbora Bruant understand the fermion learning physics. 57 Intersecting Storage Rings, BACKGROUND 74 Gulejova. 49 mass hierarchy. 51 the first hadron collider.38 www.caenels.com CERN COURIER MARCH/APRIL 2021 3 MASTER - February 2021_Paolo.indd 1 05/02/21 13:20 CCMarApr21_Contents_v3.indd 3 12/02/2021 09:42 CERNCOURIER www. V OLUME 6 1 N UMBER 2 M ARCH / A PRIL 2 0 2 1 edwardsvacuum.com CERNCOURIER.COM ENABLING RESEARCH IN UHV FROM THE Edwards are able to supply a total • Primary pumps nXDS dry scroll EDITOR vacuum package from UHV through to pumps and RV oil sealed rotary vane atmospheric pumping from a range of pumps for excellent ultimate and products including: superior vapour handling • Ultra-high vacuum Gamma Ion With our advanced modelling The rewards of bold thinking pumps for low cost and vibration capabilities and years of experience free operation in scientific research, rest assured ack in the early 1960s, as this month’s cover feature European strategy for particle physics, CERN is exploring the Edwards has the vacuum expertise to describes (p38), discussion raged at CERN about the most ambitious long-term technological path in undertaking • High vacuum nEXT and STP meet your application requirements. Bnext best step for particle physics. At the time, the high- a feasibility study for a future circular hadron collider with a turbomolecular pumps including energy frontier was commanded by the great proton synchro- centre-of-mass energy of at least 100 TeV. If built, the success versions for high throughput and [email protected] trons, such as Brookhaven’s Cosmotron and, later, CERN’s of this mother of all hadron colliders will have each generation Proton Synchrotron, which drove fixed-target experiments. of previous machine and its detectors to thank. radiation hardened designs But a new type of machine capable of exploiting the full energy Matthew of proton beams for the production of new particles – the Know your limits Chalmers hadron collider – was revving up in the sidelines. In Decem- As productive as hadron colliders are in probing nature at Editor ber 1965 the CERN Council approved the construction of the the highest energies, many current mysteries, such as dark more technologically innovative Intersecting Storage Rings matter and the origin of neutrino masses, may well origi- (ISR) over a very high-energy proton synchrotron, although nate from phenomena at the latter would materialise 10 years later in the Super Proton energy scales inaccessible Synchrotron (SPS). The ISR’s first proton–proton collisions, to any collider imaginable. which reached a centre-of-mass energy of 62 GeV, took place Fortunately, models involv- on 27 January 1971, opening the era of hadron colliders. ing such scales can be tested From the ISR came the ingenious conversion of the SPS now and in the near future by a CERN-PHOTO-201802-030-9 into a proton–antiproton collider (Spp–S), the demonstration series of experiments – some of large-scale superconducting magnet technology for the using magnets from the LHC Tevatron at Fermilab, and the LHC, whose elegant magnet and HERA in fact – searching design has enabled the highest collision energies (13 TeV) for very weakly interacting and luminosities to date. Each machine, and its increasingly “slim” particles that arise complex detectors, was a step into the unknown, requiring in extensions of the Stand- the invention of new technologies and sharp political and ard Model (see p25). Effective organisational skills to build and operate ever larger facil- field theory is another power- ities. The payoff was the discovery of the Standard Model’s ful tool to pursue such signals cornerstones: the W and Z bosons at the Spp–S, the top quark from far beyond the TeV scale, at the Tevatron, and the Higgs boson at the LHC. Not to be Discovery machine The LHC. explains Steven Weinberg in omitted from the hadron-beam collider success story are the this issue’s interview (p51). leaps in understanding of strongly interacting matter brought Meanwhile at CERN: ATLAS reports the first evidence for a Each machine, about by Brookhaven’s Relativistic Heavy-Ion Collider and the rare “Dalitz” decay of the Higgs boson (p17); pulsed-mode anti- and its LHC, and the deep-inelastic scattering experiments at DESY’s hydrogen paves the way to test antimatter in free fall (p7); and increasingly so-far unique electron–proton collider HERA, which revealed the CLOUD experiment reveals a new mechanism that could complex the proton’s innards in full colour. accelerate the loss of Arctic sea ice (p9). Elsewhere in this issue: H a l f a c e nt u r y a f t e r t h e ISR’s fi r s t c ol l i s io n s, a n d w it h a t l e a st quantum sensors target gravitational waves (p10); X-rays go detectors, was 15 years of LHC operations still to come, particle physicists behind the scenes of supernova 1987A (p12); a high-performance a step into o n c e a g a i n fi n d t h e m s e l v e s d e b a t i n g t h e n e x t b e s t s t e p for the computing collaboration forms to handle the big-physics data the unknown fie l d.
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