CERNCOURIER
58
Notes and observations from the high-energy physics community
CERN COURIER JULY/AUGUST 2019BACKGROUND
CERNCOURIER.COMAs part of a series of celebrations to mark Peter Higgs’ 90th birthday,
the University of Edinburgh launched a competition for primary-
school children in Scotland to design a birthday card. Hundreds
of entries were received, and the winning cards in each age group
(ranging from age 4–12) were presented to Higgs at an official birthday
dinner on 29 May. While these and the runners-up designs are indeed
inspired (see below), we can’t help but feel that the students missed
a trick by not riffing on the famous pre-Higgs discovery “blue-
band” plot, in which a global χ^2 fit of electroweak parameters had a
minimum at a Higgs mass of around 90 G eV/c^2.Designs on Higgs at 90
1996 km
Total length of optical fibres
and copper cables that will be
installed or removed during the
current two-year shutdown of
CERN’s accelerator complexTbilisi under the spell of Charm
About 800 physicists from many
parts of the world attended the
18th International Conference on
High Energy Physics, one of the
biennial Rochester Conferences,
in July 1976 in Tbilisi, the capital
of the Georgian Soviet Socialist
Republic. With events found at CERN, Fermilab, DESY and SPEAR,
the consensus clearly was that particles bearing the new quantum
number, charm, have been found. And the charm was not ‘hidden’,
as in the J/ψ and ψ′, but unashamedly ‘naked’, with characteristic
decays involving leptons and strange particles and ‘exotic’
relationships between electric charge and strangeness. The
discovery of charm confirms one of the more striking aspects of a
theory developed over several years by many authors. One version,
sometimes called the ‘standard model’, is based on the work of
Weinberg and Salam and of Glashow, lliopoulos and Maiani. The
theory is proving powerful in predicting phenomena such as neutral
currents, and the understanding brought about by its unification of
electric and weak forces has been compared to that achieved by
Maxwell in unifying electricity and magnetism.
Compiled from text on p252 of CERN Courier July/August 1976.Compiler’s note
With the second generation of quarks complete, the
search was on for a third pair, predicted by Kobayashi
and Maskawa in 1973 and named “top” and “bottom”
by Haim Hartari. Lederman’s team at Fermilab found
the bottom in 1977, but it took another 18 years before
the 173 GeV/c^2 top was finally discovered in 1995,
also at Fermilab, 86,500 times heavier than the lightest
up quark.From the archive: July/August 1976
Media corner
“We will look at this possibility and
will continue to maintain contacts
with you on that matter.”
Russian prime minister Dmitry
Medvedev, who visited CERN on
10 June, quoted by Russian news
agency TASS on the topic of Russia
becoming a CERN Member State.“The discovery doesn’t radically
change our perspective on physics
yet because it matches theoretical
predictions – and it certainly isn’t a
warp engine.”
Theorist Chanda Prescod-Weinstein
on the discovery of CP violation in
charm mesons and its connection
to Star Trek propulsion systems
(New Scientist 15 June).“It is not intended to be used as a
verification tool for a specific theory
but as a means of paving multiple
experimental paths for the future.”
Grigoris Panoutsopoulos and
Frank Zimmermann writing inScientific American (17 June) about
the Future Circular Collider and
whether theory or experiment
should come first.“Our new buildings do have
photovoltaics on the roofs and a
lot of insulation, but if I have one
or two million Euros to spend,
obviously it is better to inject it into
the 90% of energy consumption
[used by the machines, detectors
and computing] rather than the
10% [the buildings use].”
Frédérick Bordry, CERN director of
accelerators and technology,
discussing the environmental
credentials of large laboratories in
the June issue of Physics World.“Particle accelerators can be seen as
analogues to Anton Chekhov’s gun:
if there’s one shown in the first act,
it must be fired in the third.”
From a review of Particle Panic!
How Popular Media and Popularized
Science Feed Public Fears of Particle
Accelerator Experiments (Spr inger
2019) in Cosmos magazine, 15 June.D CheskinD Ricci/2019-070-1The four quarks— Up, Down, Strange,
Charm — sketched by rapporteur
A de Rujula.Cabling in
the SPS
tunnel.CCJulAug19_Background_v3.indd 58 28/06/2019 09:00