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News from ICTPSpecial Edition, SUSY 2013

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SUSY 2013:The Tradition Continues

ICTP is pleased to host the 2013 International Confer-ence on Supersymmetry and Unification of Funda-mental Interactions.

Now in its 21st year, the annual SUSY conference is the world’s largest international meeting devoted to high energy physics, where the community of physi-cists working in physics beyond the Standard Model comes together to explore and analyze new ideas. This year’s meeting comes at a particularly exciting time, in light of the recent discoveries at CERN’s Large Hadron Collider (LHC). Indeed, members of the LHC experiments ATLAS, CMS and LHC will discuss the latest experimental results.

However, the conference’s main focus remains on theoretical and phenomenological aspects of super-symmetric theories, and this year’s SUSY conference upholds that tradition, featuring a number of plenary lectures and parallel sessions lead by some of the world’s top theoretical physicists, including Nima Ar-kani-Hamed, John Ellis and Lawrence J. Hall. Parallel sessions will cover topics ranging from Higgs physics, dark matter and cosmology, string theory, flavour, and non-SUSY models.

In addition, the organizers of SUSY 2013 hope to broaden the appeal of physics with its planned public lectures (to be held in Trieste) by Luciano Maiani, former director general of CERN and current chair of ICTP’s Scientific Council, and Sergio Bertolucci, CERN’s research director. The lectures will be moder-ated by Trieste science journalist Fabio Pagan.

In light of the SUSY conference, ICTP takes the oppor-tunity to present its own SUSY-related research. This newsletter highlights the work of the Centre’s High Energy, Cosmology and Astroparticle Physics section. Along with a guest editorial by Gordon Kane, a mem-ber of the SUSY International Advisory Board, we hope this issue of News from ICTP gives you a deeper understanding of the ICTP-SUSY connection.

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Editorial

have their observed masses. The Standard Model pre-dicted the existence of the Higgs boson, the quantum of the Higgs field, in the early 1970s.

The Higgs boson discovery at the CERN Large Hadron Collider (LHC) was reported a year ago, completing the Standard Model. Although the Standard Model is amazingly successful in describing the world we see, it leaves a number of questions unanswered. Some are ‘why’ questions, such as: why does the Standard Model Lagrangian take the form it does? Some ques-tions are about why quark and lepton masses have the values they do (the Higgs mechanism allows them to have mass but does not explain their values), and some are about cosmological issues such as the dark matter of the universe. The properties of the Higgs boson point to directions to focus on in order to an-swer these ‘why’ and cosmological questions.

The actual properties of the observed Higgs bos-on were somewhat surprising, although they were among those predicted by some workers. Over the years from the proposal a Higgs boson should exist to its discovery, a number of approaches to the under-lying theory for Higgs physics were developed. The observed Higgs boson favoured two of those. The

he Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, will host the 2013 annual International Conference on

Supersymmetry. The timing is auspicious, and having the conference at ICTP is appropriate, as we will see in the following. Everyone is aware that particle physics has entered a new era with data from the Large Hadron Collider at CERN, and dark matter ex-periments. In addition, it is an exciting time because there is increasingly a theoretical framework based on supersymmetry and progress in M/string theories compactified to four dimensions that address many important questions in a unified way. ICTP and Abdus Salam have a distinguished history in super-symmetry.

Let us turn to supersymmetry and related physics. The so-called Standard Model of particle physics is an extraordinary theory. It is a full quantum field theory of the constituents of matter and of the forces that shape the matter into our world. Abdus Salam, Sheldon Glashow and Steven Weinberg got the Nobel Prize for being the first to use the Higgs mechanism to break the electroweak symmetry of the Standard Model in order to allow quarks and electrons and the W and Z bosons that mediate the weak interactions

by Gordon Kane

From left: B. Richter, L. Lederman, P.W. Higgs, H. Schopper, H.S. Virk and Abdus Salam during a

pause of the Summer Workshop in High Energy Physics and Cosmology, ICTP, Trieste, July 1987

Supersymmetry, Abdus Salam, and ICTP

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most likely one was in the framework of supersym-metry. Data on the mass and the Higgs boson decay branching ratios might help distinguish, and will be a major topic at the upcoming conference. Salam, in his 1979 Nobel Prize Lecture, presciently remarked, “To reduce the arbitrariness of the Higgs couplings … one suggestion is to use supersymmetry”. For a num-ber of theoretical and phenomenological reasons, a supersymmetric Standard Model is considered the most promising way to extend and strengthen the Standard Model.

If supersymmetry is indeed part of the laws of nature, each of the basic Standard Model particles must have a partner (differing by half a unit of the property called spin, and perhaps by mass). The initial run of the LHC has apparently not found a signal for super-partners, though most reports of limits are exagger-ated; for example, the actual limits for the gluinos (the superpartners of the gluons that mediate the strong force) are significantly less than a TeV in the string theory that correctly predicted the Higgs mass, though the most publicized limits from oversim-plified models are well over a TeV. The LHC is being upgraded in energy and intensity and the searches for superpartners will be the highest priority when run-

ning begins again in about a year and a half. At this writing a significant part of the data from the first run had not yet been analyzed for the best motivated sig-natures, so there is still a chance of a hint of a signal emerging by the ICTP meeting at the end of August.

The word “supersymmetry” first appeared in a paper by Salam and John Strathdee in 1974. Salam and Strathdee also introduced the concept of superspace that year (as did Julius Wess, Bruno Zumino, and Ser-gio Ferrara independently), and Salam and Strathdee wrote the theory for the non-abelian case also in 1974 (as did Ferrara and Zumino independently). In that era, ICTP was one of a few worldwide top centres for research in supersymmetry.

Salam died after a long illness in 1996 at the age of 70. In his Nobel Prize Lecture he suggested, “There may, however, be indications of a next level of structure around 10 TeV”.

Gordon Kane is Victor Weisskopf Distinguished Uni-versity Professor of Physics at the University of Michi-gan, and Director Emeritus of the Michigan Center for Theoretical Physics

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CTP’s High Energy, Cosmology and Astroparticle Physics (HECAP) section has played a major role in organizing SUSY 2013, which ICTP is hosting

this year from 26 to 31 August 2013. This conference on Supersymmetry and Unification of Fundamental Interactions, considered one of the most important in the field of high energy and particle physics, comes at a time when particle physics is on the cusp of enter-ing unexplored territory that lies beyond the experi-mentally verified Standard Model predictions.

Particle physics at ICTP has always been represented by leaders in the field right from the time of ICTP’s founder and first director Abdus Salam, who was awarded the Nobel Prize in 1979 for his work on elec-troweak unification theory. ICTP continues to have a strong particle physics research focus; the group includes Alexei Smirnov, whose contributions to the field include uncovering the matter effect (now called the Mikheyev-Smirnov-Wolfenstein effect) in neutri-nos; Bobby Acharya, who heads ICTP’s contribution to the ATLAS experiment at CERN; Goran Senjano-vicć, who proposed the seesaw mechanism that can possibly explain the tiny masses of neutrinos; and the newest HECAP staff scientist, Giovanni Villadoro, whose research focus is Large Hadron Collider (LHC) physics, phenomenology, and physics beyond the Standard Model, in particular, supersymmetry.

Acharya and Villadoro are part of the SUSY 2013 organizing committee, along with HECAP scientist Paolo Creminelli, whose research focus is cosmol-ogy; Kumar Narain, string theorist and head of the HECAP section; and ICTP Director Fernando Queve-do. Explaining why the concept of supersymmetry (or SUSY) is important, Villadoro says, “Supersymmetry is one of the main candidate theories that has been proposed to explain physics beyond the Standard Model, that is, beyond the physics we know at the moment.”

With the recent LHC discovery of a Higgs boson-like particle, the last ‘missing piece’ of physics as predict-ed by the Standard Model may have been discovered.

SUSY Research at ICTP

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“The timing of this conference [SUSY 2013] is perfect in light of the recent LHC results,” says Narain.

But, some questions have remained. For example, why does the discovered Higgs boson-like particle have a mass much lighter than expected? What is the nature of dark matter? Is the unification of the forces at the subatomic level (electromagnetic, strong and weak forces) possible? Villadoro, like many theoretical physicists, thinks that the answers may lie in a super-symmetric extension to the existing Standard Model.

So, what is supersymmetry? In brief, supersymmetry is a framework that predicts the existence of a ‘part-ner’ superparticle for every known subatomic particle and puts the matter particles and force particles on an equal footing. “One of the initial motivations of supersymmetry was solving what is known as the mass hierarchy problem or the naturalness problem,” says Narain.

“The principle of naturalness has worked for many physics models in the past,” says Villadoro. “A quick explanation for the naturalness criterion is that the energy scale associated to scalar particles, such as the Higgs boson mass, receives big contributions from any physics lying at higher energy scales. It is there-fore impossible to have large separation of scales without an ‘unnatural’ cancellation of big contribu-tions. In a natural theory, such great differences in scales, as is the case of the small mass of the Higgs boson, require the presence of a symmetry to guar-antee such cancellation. Supersymmetry was consid-ered a good candidate to explain the Higgs boson’s small mass, provided the superpartners of the Higgs boson and the other known particles are detected at an energy scale somewhat close to that of the Higgs particle.”

But while there are many proponents of the super-symmetric framework, and over 10,000 scientific pa-pers on supersymmetry have been published since it was first proposed, some physicists view the idea with skepticism. Why? Because so far, no supersymmetric

Kumar NarainHECAP section head

Giovanni Villadoro

particles have been detected by any experiments, including the ones carried out at the LHC.

“During the current run, the LHC reached 8 TeV colli-sion energy,” says Villadoro, adding, “Part of the data obtained at this energy level has been analyzed and we have not found any signatures for superparticles. But, that does not completely rule out the possibility of their existence; perhaps we need to probe at higher energy levels.”

Indeed, one of the motivations for building the LHC was to look for clues to physics beyond the Standard Model and check for SUSY signatures. “LHC is now shut for the next upgrade to 14 TeV, and by 2015 we should be able to probe for SUSY signatures at higher energies,” says Villadoro. But that would still leave the problem of naturalness unsolved. “Even if SUSY is not found at LHC, SUSY remains an important theoreti-cal framework for understanding quantum gravity,” says Narain. “Indeed, string theory, which serves to provide a theory including quantum gravity, assumes the existence of supersymmetry, at least at very high energies,” he adds.

Villadoro says that this is a very interesting period to be looking at SUSY as a framework. “SUSY still has a special role to explain the new physics, and we need to wait for the next LHC upgrade to get a clearer picture,” he says. “As of today, supersymme-try offers one of the most complete pictures of the physics we know.” Narain agrees: “As any physicist, I will be thrilled if and when we detect supersymmetry particles or any hints for supersymmetry. It is one of the most elegant and beautiful theories to explain the physics of our world.”

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ith large experimental facilities giving the-oretical physicists unprecedented ability to gain deeper and fascinating insights

into particle physics, the field is set to enter interest-ing and challenging territories, according to Alexei Smirnov, principal research scientist in ICTP’s HECAP section. Smirnov, considered one of the leaders in the field of neutrino physics, is referring to neutrino detecting facilities, in particular the IceCube detec-tor—a facility located at the South Pole that records neutrino interactions.

Smirnov, whose work on neutrino oscillation estab-lished him as an authority in the field, is current-ly working on three main themes: neutrino mass ordering and CP violation; possible existence of new neutrino species, sterile neutrinos; and theoretical aspects of flavour physics.

The IceCube detector, which is providing important data to neutrino physicists, consists of many thou-sands of sensors (Optical Modules) arranged on “strings” that are distributed over a cubic kilometre under the Antarctic ice. Within this string arrange-ment is the DeepCore region, which has more densely packed strings and can detect particle interactions below 100 GeV. “Using DeepCore experiments, we can see interactions at low energies and also learn more about the properties of neutrinos,” says Smirnov.

“Specifically, I want to use the detector data to estab-lish neutrino mass ordering [determining which neu-trino types are heaviest and lightest],” says Smirnov. “As of today, we know that neutrinos come in three

flavours (electron, muon, tau) and have small, non-zero masses, but we do not know the hierarchy of the masses.” He explains that by using the neutrino interaction data, physicists are looking to establish neutrino mass hierarchy. “This is the next crucial goal in neutrino physics,” he says. The next upgrade to the DeepCore, dubbed PINGU (Precision IceCube Next Generation Upgrade), will bring physicists closer to determination of neutrino mass order, a crucial ele-ment for phenomenology and theory.

Another research theme that Smirnov is currently focusing on is the possible existence of new neutrino species. “New neutrino detectors, including IceCube, can search for sterile neutrinos,” says Smirnov. “Ster-ile neutrinos do not have the weak interactions that usual (active) neutrinos do. Active neutrinos can be transformed to sterile neutrinos and we can detect this disappearance effect.”

His third line of research focuses on a theoretical aspect of neutrino physics. Smirnov explains that in recent years, physicists have gathered more informa-tion about neutrino behaviour and properties—os-cillations, mixing and masses. And, there are hints of an existing symmetry in neutrino mixing. Smirnov and HECAP postdoctoral fellow Daniel Hernández are working on a formalism to explore patterns of this neutrino mixing.

“I expect important aspects in neutrino physics to be uncovered in the near future,” says Smirnov.

Next Steps in Neutrino Physics

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n 14 March 2013, two collaborating experi-ments (ATLAS and CMS) at the Large Hadron Collider (LHC) announced their new results

that reconfirmed the findings presented at CERN in July 2012: the particle discovered last year is very like-ly the Higgs boson. Bobby Acharya, research scientist with ICTP’s HECAP section and head of ICTP’s contri-bution to the ATLAS experiment (working in collabo-ration with the University of Udine under the umbrel-la of the Italian National Institute of Nuclear Physics), says that there are many aspects of the discovery that will be studied in greater detail.

Acharya says that the physicists will now try to de-velop even more sensitive measurements of the spin and parity. Another aspect they want to measure in greater detail is the Higgs boson interaction with all particles, as it is responsible for the masses of Stand-ard Model particles and interacts with all particles.“At the moment, we don’t have very sensitive meas-urements of the interaction of the Higgs with fermi-ons, i.e., quarks and leptons,” says Acharya. “For the interactions with fermions, we need more data so will have to wait until the LHC starts up again in 2015.”

Explaining why it is important to understand if the Higgs boson fits into the Standard Model or goes beyond it, Acharya says, “This is of paramount impor-tance! The Higgs—being the giver of mass—couples directly to all particles with mass and even indirectly to all particles without mass (e.g., photons). So, if there is physics beyond the Standard Model, then we expect some properties of the Higgs to be different with respect to the Standard Model.” Elaborating on

this, Acharya says that there could be new particles, which are light enough for the Higgs to decay into. “An example could be new neutral particles, which are dubbed “invisible Higgs decays” since the neutral particles would escape detection like the neutrinos,”he says.

Currently, the Udine/ICTP ATLAS group is working on invisible Higgs decays. Loan Truong (a former ICTP diploma student from Vietnam and now a SISSA/ICTP PhD student) and Acharya are work-ing on this together with ATLAS physicists from Brookhaven National Laboratory, University of Texas at Arlington, University of Wisconsin and University of Montreal. “In general, we will look for ‘excesses’ or ‘deficits’ in the number of Higgs decays into a given final state with respect to the Standard Model,” explains Acharya.

Acharya and the ATLAS collaboration will be pub-lishing their results on invisible Higgs decays in the coming months.

What’s Next for the Higgs Boson?

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xplaining the origin of neutrino mass and understanding the nature of symmetry has been central to Goran Senjanovic’s career as a

particle physicist. Senjanovic’s paper (with his adviser Rabindra Mohapatra) on the seesaw mechanism, which unveiled the mystery behind the smallness of neutrino masses, and his work on left-right symmetry of electroweak interactions are considered milestones in particle physics.

“In 1974, when I was starting my graduate studies, Jogesh Pati and Abdus Salam published their work on left-right symmetry and my world of research opened up,” says Senjanovic, talking about how he began his nearly four decade-long career as a theoretical phys-icist. In 1979, Salam and Steven Weinberg shared the Nobel Prize in Physics with Sheldon Lee Glashow for their work on the theory of the unified weak and elec-tromagnetic interaction, and this contributed to the basis for Senjanovic’s future work in particle physics.

Senjanovic went on to build upon the theory that left-right symmetry can be spontaneously broken and according to this theory neutrinos were supposed to have masses. “This [neutrinos having masses] was a curse because the standard model assumed that neutrinos were massless,” says Senjanovic. But later experiments showed that neutrinos oscillate (i.e., they are created in one flavour [electron, muon, tau] but can change the flavour) and oscillation is possible only if neutrinos have non-zero masses.

“With the seesaw mechanism, Mohapatra and I were able to explain why neutrinos have tiny masses,” says Senjanovic. Senjanovic and Mohapatra’s paper on

the seesaw mechanism would go on to become one of the highest cited papers in the field. “All particles have left- and right-handed species capable of in-teractions. But with neutrinos it was different; it was assumed that neutrinos existed only as left-handed particles that could have weak interactions,” explains Senjanovic. “We postulated that a gauge boson medi-ates right-handed weak interactions in neutrinos and that the right-handed neutrinos could be seen only at a high energy scale.”

At one point, Senjanovic shifted research focus because many of these theories could not be tested, until the Large Hadron Collider (LHC) came into play. With the LHC, it became possible to probe for par-ticles at high energy scales. “Over the last few years, I have gone back to work on things that I started 30 years ago because the LHC has made it feasible to test the theories,” says Senjanovic.

“In the recent years I have worked with ICTP postdoc-toral fellow Miha Nemevsek, former postdoctoral fel-low Yue Zhang and former diploma student Vladimir Tello, expanding on these theories of left-right symmetry. I am particularly proud of a paper titled ‘Left-Right Symmetry: From Majorana to Dirac’, that Nemevsek, Tello and I published in 2012.”

“Today, with large experimental facilities like the LHC, I see a possibility of probing the Higgs mech-anism for neutrinos and establishing the origin of neutrino mass,” says Senjanovic. “And, understanding the origin of neutrino mass and the nature of symme-try has always been my main motive in physics.”

The Nature of Symmetry and Neutrino mass

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he European Space Agency (ESA) released its Planck space telescope observations on 21 March 2013. And with this data, scientists now

have more precise information about the age, con-tents and origins of our universe. The observations, collected over 15 months, were compiled into a col-ourful map of cosmic microwave background (CMB) radiation, showing the oldest light and fluctuations in temperature that were imprinted on the deep sky when the universe was about 370,000 years old.

Paolo Creminelli, research scientist at ICTP’s High Energy, Cosmology and Astroparticle Physics section, says that the Planck experiment is a pinnacle of hu-man achievement. “There was no question of second chances in this experiment,” he says. “Everything from the launch of the satellite to obtaining data had to be precise, and it was. In fact, one can say the experiment went better than planned.”

Creminelli, whose research interests include inflation, in particular non-Gaussianity, and alternatives to inflation, says that with the Planck results we know all the cosmological parameters better than before. “The experimental results are so precise that they will possibly remain state-of-the-art for the immediate foreseeable future,” he says.

In terms of theoretical cosmology, the Planck results are consistent with the Standard Model. “The data has allowed us to rule out many complex inflation theories in favour of simple ones,” says Creminelli. “So, while we know our universe with a precision like never before, the results do not reveal anything remarkable.”

But what do these data mean for SUSY? Some scien-tists have hoped to find hints to supersymmetry in the CMB. Since supersymmetry predicts existence of new superparticles, scientists theorize that some of these superparticles could make up the mysterious dark matter that constitutes approximately 27% of our universe. However, the currently-released Planck data does not provide explicit evidence for SUSY in the CMB.

But other experiments may offer more solid hints. Gabrijela Zaharijas, a postdoctoral fellow in the HECAP group who works on dark matter, says that a rich lineup of experimental programmes, including Fermi LAT, Alpha Magnetic Spectrometer (AMS), nuclear recoil experiments such as XENON and LUX, the next run of LHC in 2015, and the next round of Planck in 2015, together with future experiments like the Square Kilometre Array and Cherenkov Telescope array, are expected to provide more concrete indi-cations to whether the SUSY framework can explain the nature of dark matter.

Can SuSy explain the Nature of Dark matter?

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The 2012 ICTP Prize has been awarded to Argentine-an physicist Pablo Mininni, a professor at the Uni-versity of Buenos Aires (UBA). The prize recognizes Mininni’s important contributions to advancing the understanding of fluid and magnetofluid turbulence at a fundamental theoretical level as well as work-ing out a range of applications in astrophysics and atmospheric sciences.

“Turbulence is ubiquitous in many flows in nature, and working on this problem has given me the op-portunity to work in collaboration with astronomers, solar and space physicists, atmospheric scientists, and mathematicians,” says Mininni. He enjoys work-ing on problems in fluid dynamics, and more specif-ically problems related to turbulent flows, because of the broad range of applications of the field, including applications in the generation of magnetic fields by turbulent flows in the Sun and in the Earth’s core, as well as turbulence in plasmas and in rotating flows. “More recently, I became interested in mechanisms that give rise to the generation of helical (non-mirror symmetric) flows in stratified turbulence, a problem that can be relevant for atmospheric and geophysical systems,” he adds.

Mininni received his PhD from UBA and went on to work at the National Center for Atmospheric Research (NCAR), USA. “As a PhD student I attended several schools at ICTP and it gave me the opportunity to network with top scientists in my area of research,” he says. “The experience has always been fantastic.” Apart from being a visitor to the Centre, Mininni has been collaborating with ICTP to implement the openEyA system (ICTP’s automated recording system) at UBA.

Mininni says that the prize has come as a huge sur-prise to him and he feels honoured. “These recogni-tions are really important, not only for the research-

Research on turbulence theory and applications honoured

ers, but also for the scientific community,” he says. “It is certainly reassuring when institutions give these recognitions and support the work scientists do.” Mininni adds that the ICTP Prize is especially encour-aging because it “comes from an institution with a central commitment to the development of science in developing countries.”

The ICTP Prize was created in 1982. It recognizes young scientists (under 40) from developing coun-tries who work and live in those countries and who have made outstanding and original contributions to physics. The prize includes a sculpture, certificate and a cash award of €3,000. To view the full citation of Mininni’s award, as well as a list of past winners, see the ICTP Prize webpage at www.ictp.it/about-ictp/prizes-awards/the-ictp-prize.aspx.

Each year, the ICTP Prize is given in honour of a scientist who has made outstanding contributions to the field in which the prize is given. The 2012 ICTP Prize honours Marshall N. Rosenbluth (1927-2003), an American plasma physicist and member of the National Academy of Sciences. He made contribu-tions to discoveries in controlled thermonuclear fusion, plasma physics, and computational statistical mechanics.

In 1964, with the encouragement of Abdus Salam, he organized ICTP’s first activity, a plasma physics work-shop that would gain historical significance by bring-ing together in Trieste leading plasma physicists from the Soviet block and Western countries. He headed the plasma physics research activities in 1965-1966, and became a member of the ICTP Scientific Council between 1975 and 1982.

2012 ICTP Prize Awarded toArgentinean Physicist Pablo mininni

ICTP Awards

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ICTP and the International Mathematical Union (IMU) announced that the 2013 Ramanujan Prize for Young Mathematicians from Developing Countries will be awarded to Professor Ye Tian, Academy of Mathematics and Systems Science, Chinese Academy of Sciences.

The prize is in recognition of his outstanding contri-butions to Number Theory. These include the com-pletion of the proof of a multiplicity one conjecture for local theta correspondences and important work related to Heegner points and to the Birch and Swin-nerton-Dyer conjecture: the non-existence of points on twisted Fermat curves, and recently remarkable progress on the congruent number problem, showing the existence of infinitely many congruent numbers with arbitrarily many prime factors. The Selection Committee consisted of Augustin Banyaga, Ngô Bào Châu, Zhi-Ming Ma, and Lothar Göttsche (Chair). The Prize is funded jointly by ICTP and the IMU.

Mohammad Dhafer Al-Amri of Saudi Arabia has been awarded the 2013 International Commission for Optics (ICO)/ICTP Gallieno Denardo Award at the annual Winter College on Optics held at ICTP.

Al-Amri is an associate professor at the National Centre for Mathematics and Physics, King Abdul-Aziz City for Science and Technology (KACST) in Saudi Arabia. The award cites his pioneering research in the field of optical lithography and microscopy, quantum teleportation of multi-qubit systems, and the reversal of weak measurements in optical systems. The award also recognizes Al-Amri’s leadership role in establish-ing a quantum optics research programme at KACST under difficult circumstances.

ICTP and the ICO established the award to recognize a researcher under 40 years of age from a developing country who has made significant contributions to the field of optics.

The recipient receives a certificate, US$1,000, and an invitation to participate in and deliver a lecture at an ICTP activity relevant to optics.

The award is named in honour of Gallieno Denardo, who coordinated optics activities at ICTP for more than twenty years.

Award goes to Chinese mathematician Saudi Arabian scientist wins this year’s ICO/ICTP prize

2013 ramanujan Prize Announced

optics Award Announced

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Can using only high-end climate models to study climate change mean losing sight of the forest for the trees? Yes, according to ICTP scientists Fred Kucharski and Riccardo Farneti of the Centre’s Earth System Physics section. To avoid the situation where the climate community is too lost in details to see the big picture, Kucharski and Farneti emphasize the impor-tance of using “intermediate complexity models”.

In their recently published paper titled “On the need of intermediate complexity general circulation mod-els”, which appeared in the Bulletin of the American Meteorological Society (Volume 94, Issue 1), Kucharski and Farneti stress the importance of intermediate complexity models, using SPEEDY (Simplified Param-eterizations, primitivE-Equation DYnamics) as an example.

SPEEDY is an atmospheric general circulation model (AGCM) that has been developed at ICTP. “While this kind of model may not be used to study every aspect of climate change, it can be used to study the funda-mental dynamics that affect climate systems,” says Farneti. “Rather than making climate projections, the model tries to answer why climatic variations occur.”

“Intermediate complexity models can run with lower computational power,” says Kucharski. “Moreover, many of them are freely available for download and use.”

The memory requirement to run SPEEDY, for exam-ple, is about 35 MB, and it can run on older desktop computers with low hardware specifications. “This means the models can be used by researchers from

Intermediate complexity models can keep things simple and provide robust results

Seeing the Big Picture on Climate Change and variability

developing countries and by graduate students who have access to limited resources,” adds Farneti.

“If you look at the mean climate, the results obtained using SPEEDY are as good as those from the best models,” says Kucharski. Both Kucharski and Farneti say that the aim is to keep things simple and provide a modelling system that can run on inexpensive computational equipment and at the same time allow efficient investigations for a broad range of research questions arising in the field of Earth-system science.

Fred Kucharski and Riccardo Farneti

Research and Training

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Although the Kondo effect—a phenomenon that arises from the interactions between a single mag-netic atom and the many electrons in a non-magnet-ic, metallic host—was discovered in the 1930s and explained in the 1960s, it continues to be a subject of interest to condensed matter physicists, especially those studying matter at the nano scale. That is be-cause it can help scientists to understand electronic transport through artificially created nano-objects, including semiconductor quantum dot transistors and molecular electronic devices.

When the Kondo effect is observed in a nano-device that is sandwiched between two large electron seas in two electric contacts (leads), the many-electron state arising due to a resonance scattering on the magnetic impurity is usually referred as a “Kondo cloud”. Whether it is possible to measure and control a Kondo cloud is still under ongoing debate.

The ability to control a Kondo cloud in mechanical nano-devices would allow the possibility for a super-high tunability of mechanical dissipation as well as supersensitive detection of mechanical displacement.

In order to find a resolution to the problem of Kondo cloud detection, ICTP scientist Mikhail Kiselev and an international team of researchers suggested an approach using nano-electromechanics.

Nano-electromechanics is a new and rapidly devel-oping field of modern quantum transport condensed matter physics. It typically deals with devices that contain mechanical and electronic components that are strongly coupled to each other.

Article explores dynamics of Kondo effect in nano-electromechanics

Condensed matter research Published

In a paper published online on 5 February in Physical Review Letters and titled “Kondo force in shuttling devices: dynamical probe for a Kondo cloud”, Kiselev and his colleagues from Chalmers University of Tech-nology, University of Gothenburg and Tel-Aviv Uni-versity reveal findings from a study of the Kondo force on a quantum dot attached to a vibrating cantilever, by which they can follow the inertia of a Kondo cloud.

“If this cloud exists, and if we start to move spin which is a quantum impurity, then the cloud will follow it with some retardation. Our paper addresses the question of how to calculate and measure this re-tardation effect and what kind of information we can get from this, both theoretically and experimentally,” states Kiselev.

Kiselev adds that the research can have application in spintronics, molecular electronics, and be imple-mented in various types of nano-devices. “In particu-lar, one of the application of nano-electromechanics is in metrology, allowing the measurement and detec-tion of tiny electrical currents,” he explains.

He adds that this idea of using dynamical probes to study Kondo clouds opens new possibilities for stud-ying non-equilibrium phenomena which account for spin and combining non-equilibrium physics with the effects of strong correlations and resonance scattering.

Coloured image of a mechanical single electron transistor. The gold island located at the center of a string can shuttle electrons between the source

and drain electrodes when excited by ultrasonic waves

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Nuclear and radioactive materials, though useful and beneficial in many fields including energy, medicine, agriculture and industry, could pose a danger to the environment and to the public if handled improperly.

To help developing countries build effective nuclear security strategies, ICTP and the International Atomic Energy Agency (IAEA) conducted the third annual International School on Nuclear Security in Trieste from 8 to 19 April 2013.

The school, which combined ICTP’s international network of researchers in developing countries with IAEA nuclear security expertise, plays an essential role in supporting countries’ efforts to prepare ex-perts who are well equipped and qualified to analyze national nuclear security needs, prevent and combat the threat of sabotage or the use of nuclear and ra-dioactive material for criminal or unauthorized acts, and prepare effective response measures to nuclear security events.

This year’s school attracted 182 applicants, of which 48 were selected, representing 39 countries (7 of which are least-developed countries). Participants came from regulatory authorities, universities, re-search institutes, national ministries, and law en-forcement agencies.

It is probably one of ICTP’s more unusual scientific activities, but the College on Soil Physics has been going strong; this year marked the 30th anniversary of the College, which ran from 25 February to 1 March 2013. Donald Gabriels, Emeritus Professor of the Department of Soil Management, Faculty of Biosci-ence Engineering of Ghent University, Belgium, who has been a course director since the activity’s incep-tion in 1983, says that soil physics has become more relevant today than ever before. “The fields of interest have widened. Today, soil physics finds application in fields including climatology, hydrology, and agricul-ture,” he says.

The idea to establish an activity in soil physics was the result of a chance encounter between Abdus Salam and Gabriels. Although the theme was slightly outside the purview of theoretical physics, Salam quickly realized the importance of the field to the developing world. “Once Salam understood how important soil physics is to developing countries, he gave his complete support to the programme,” says Gabriels. The college has trained more than 850 participants from developing countries over the past three decades.

ICTP, IAEA hold 3rd school on nuclear security

Celebrating three decades, ICTP college highlights soil’s key role in the Earth system

Attendees of the ICTP/IAEA third annual

International School on Nuclear Security

College on Soil Physics participants

Promoting ‘nuclear security culture’ in the Developing World

The Importance of Soil

Research and Training

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News Highlights

A school on superstring theory held at ICTP in April 2013 featured lectures by leading researchers in the field, including Juan Martín Maldacena, from the Institute for Advanced Study, Princeton, USA, a win-ner of the Fundamental Physics Prize in 2012 and a member of ICTP’s Scientific Council. Maldacena, who was awarded ICTP’s Dirac Medal in 2008, has a long association with the superstring school and ICTP; this year he lectured on “Black holes in quantum gravity”.

“String theory is a long-term endeavour, and it is guided mostly by looking at the mathematical con-sistency of the theories,” says Maldacena, adding that string theory continues to be of interest because it has applications across fields. “For example,” he says, “through the gauge gravity duality to problems in condensed matter physics, in nuclear physics, in quark gluon plasma, and so on, and it can be used as a model to solve a variety of problems.”

Maldacena first came to the ICTP school as a student in 1994. “It has always been of a very high quality, and it is a good place to hear about the latest develop-ments in the field,” he says.

Juan Martín Maldacena discusses black holes, gauge theories, string theory and gravity

2012 Fundamental Physics Prize Winner lectures at ICTP

ICTP and the Kuwait Foundation for the Advance-ment of Sciences (KFAS) have agreed to a new joint programme of support for scientists from Kuwait and the Arab world to be involved in ICTP research and educational activities.

The Kuwait Programme at ICTP helps scientists participate in key activities at ICTP: Scientific Calen-dar events such as conferences and workshops; the Postgraduate Diploma Programme; and postdoctor-al work.

ICTP, KFAS agree to renewed support for scientists from the Arab world

A Boost for Arab Science

The Director General of KFAS, Dr. Adnan Shihab-El-din, formalized the agreement at a meeting held on 22 March in Trieste with ICTP Director Fernando Quevedo and the Centre’s top scientists. “KFAS is pleased to be a part of ICTP’s unique forum for North-South science collaboration,” Shihab-Eldin said, adding that KFAS has been supporting the engagement of Arab scientists in ICTP activities for more than 30 years.

“This long-term cooperation between ICTP and KFAS represents the spirit of ICTP’s core mission to foster the growth of advanced studies and research in physical and mathematical sciences, especially in support of excellence in developing countries,” said Director Quevedo.

Three-dimensional printers—printers that can pro-duce solid objects out of plastic or other materials—are quickly capturing the world’s imagination. ICTP has opened a 3D Printing Lab to promote the use of this new, low-cost technology in science education for developing countries.

“We designed this lab to be a friendly, modern place open to creativity,” said Enrique Canessa, coordinator of ICTP’s Science Dissemination Unit (SDU). Canessa, along with colleagues Carlo Fonda and Marco Zenn-aro, assembled the lab and promoted the technology at a workshop on 3D printing for science education and sustainable development that they organized in May.

“We are interested in 3D printing because of its many applications, and with its low cost it can be an acces-sible technology for the masses,” explained Canessa. Added Fonda, “We want to expose Lab visitors to this technology to see what they may invent to fit their needs.”

SDU’s hope is that the printers will make an impact in developing countries. Their low cost and open source instructions already make the printers an attractive technology for cash-strapped countries, and with SDU’s training assistance, developing countries could easily adapt this new technology.

ICTP opens 3D Printing labCutting-edge technology opens new dimensions to science education

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giovanni villadoro, a theoretical physicist with a background in LHC physics, phenomenology, and physics beyond the Standard Model, has been appointed to ICTP’s High Energy, Cosmology

and Astroparticle Physics (HECAP) section as a re-search scientist. Villadoro was a research associate at the SLAC National Accelerator Laboratory, Stanford University, prior to his appointment at ICTP.

He obtained his PhD from the University of Rome “La Sapienza” and went on to pursue postdoctoral work at Harvard University followed by a fellowship at CERN.

yamiko Samu is ICTP’s new institute advancement officer, assisting the Centre in effectively pursuing new public and pri-vate funding for its key strategic initiatives. For the past 15 years,

Samu has worked for Habitat for Humanity, an in-ternational, non-profit organization that builds and rehabilitates affordable housing around the world. Starting as a field officer in Habitat’s Malawi office, Samu worked his way up through the organization’s branch in South Africa and then its headquarters in the US, where he was a fundraising officer. He has a BA degree in economics and computers from the University of Malawi and completed postgraduate studies in public policy and management at the Uni-versity of London.

New Staff

In Memoriam

It is with great sadness that ICTP learned of the death of Padma Kant Shukla, a frequent visitor to ICTP and a distinguished professor of phys-ics at Ruhr University Bochum, Germany.

Shukla, who was an important figure in the field of plasma physics and held the Ruhr University Bochum International Chair in the Faculty of Physics and Astronomy, had participated in ICTP training activities in plasma physics for more than two decades, serving as a course director for workshops and colleges on plasma physics since 1995.

Nigerian-born Professor Emeritus James O.C. Ezeilo began his asso-ciation with ICTP in the early 1970s by participating in mathematical activities. He then became a member of the ICTP Scientific Council in the 1990s, where he represented Africa. He was a member of the Council of the Edward Bouchet Abdus Salam Institute (EBASI), and the author of nearly 100 scientific papers, and won several academic prizes and awards.

Padma Kant Shukla1950 to 2013

James O.C. Ezeilo1930 to 2013

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The Abdus Salam International Centre for Theoretical Physics (ICTP) is administered by two United Nations agencies—the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the International Atomic Energy Agency (IAEA)—under an agreement with the Government of Italy.

News from ICTP is a bi-annual publication designed to keep scientists and staff informed on past and future activities at ICTP and initiatives in their home countries. The text may be reproduced freely with due credit to the source.

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EditorMary Ann Williams

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