Tag Archives: cern

Islamic Republic of Pakistan to become Associate Member State of CERN: CERN Press Release

Geneva 19 December 2014. CERN1 Director General, Rolf Heuer, and the Chairman of the Pakistan Atomic Energy Commission, Ansar Parvez, signed today in Islamabad, in presence of Prime Minister Nawaz Sharif, a document admitting the Islamic Republic of Pakistan to CERN Associate Membership, subject to ratification by the Government of Pakistan.

“Pakistan has been a strong participant in CERN’s endeavours in science and technology since the 1990s,” said Rolf Heuer. “Bringing nations together in a peaceful quest for knowledge and education is one of the most important missions of CERN. Welcoming Pakistan as a new Associate Member State is therefore for our Organization a very significant event and I’m looking forward to enhanced cooperation with Pakistan in the near future.”

“It is indeed a historic day for science in Pakistan. Today’s signing of the agreement is a reward for the collaboration of our scientists, engineers and technicians with CERN over the past two decades,” said Ansar Parvez. “This Membership will bring in its wake multiple opportunities for our young students and for industry to learn and benefit from CERN. To us in Pakistan, science is not just pursuit of knowledge, it is also the basic requirement to help us build our nation.”

The Islamic Republic of Pakistan and CERN signed a Co-operation Agreement in 1994. The signature of several protocols followed this agreement, and Pakistan contributed to building the CMS and ATLAS experiments. Pakistan contributes today to the ALICE, ATLAS, CMS and LHCb experiments and operates a Tier-2 computing centre in the Worldwide LHC Computing Grid that helps to process and analyse the massive amounts of data the experiments generate. Pakistan is also involved in accelerator developments, making it an important partner for CERN.

The Associate Membership of Pakistan will open a new era of cooperation that will strengthen the long-term partnership between CERN and the Pakistani scientific community. Associate Membership will allow Pakistan to participate in the governance of CERN, through attending the meetings of the CERN Council. Moreover, it will allow Pakistani scientists to become members of the CERN staff, and to participate in CERN’s training and career-development programmes. Finally, it will allow Pakistani industry to bid for CERN contracts, thus opening up opportunities for industrial collaboration in areas of advanced technology.

Footnote(s)

1. CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Union, JINR and UNESCO have Observer Status.

Source : CERN

Join the hunt to break the Higgs boson ‘barrier’

Online volunteers are being asked to spot tiny explosions that could be evidence for new particles that will require new models of physics.

Higgs Hunters [www.higgshunters.org], a project launched today by UK and US scientists working on the ATLAS experiment, enables members of the public to view 25,000 images recorded at CERN’s Large Hadron Collider. By tagging the origins of tracks on these images volunteers could spot sub-atomic explosions caused when a Higgs boson ‘dies’, which some scientists think could generate a kind of particle new to physics.

‘If anything discovering what happens when a Higgs boson ‘dies’ could be even more exciting that the original discovery that the Higgs boson exists made at CERN back in 2012,’ said Professor Alan Barr of Oxford University’s Department of Physics, lead scientist of the Higgs Hunters project. ‘We want volunteers to help us go beyond the Higgs boson ‘barrier’ by examining pictures of these collisions and telling us what they see.’

In the ATLAS experiment at CERN’s Large Hadron Collider protons are smashed together at up to one billion kilometres per hour. Such collisions can generate Higgs bosons: these are known to rapidly decay into other particles and some scientists believe these could include a new type of previously unobserved particle. Simulations predict that these new particles should leave tell-tale tracks inside the ATLAS experiment, which computer programs find difficult to identify, but which human eyes can often pick out.

Professor Andy Haas of New York University said: ‘Writing computer algorithms to identify these particles is tough, so we’re excited to see how much better we can do when people help us with the hunt.’

Professor Chris Lintott of Oxford University’s Department of Physics, Zooniverse Principal Investigator, said: ‘The most exciting citizen science comes when you find the unexpected lurking amongst the data, and who knows what could be out there in the data from the ATLAS experiment?’

Professor Dave Charlton, spokesperson of the ATLAS Collaboration, said: ‘With the Higgs Hunters project, people can look directly at ATLAS data to help us find unexpected phenomena – perhaps volunteers will be able to spot new physics with their own eyes!’

A successful detection of new particles would be a huge leap forward for particle physics, as they would lie beyond the Standard Model – the current best theory of the fundamental constituents of the Universe.

Source: Oxford University

The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b'- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b'- region plotted with a finer binning.
Credit: CERN

CERN makes public first data of LHC experiments

CERN1 launched today its Open Data Portal where data from real collision events, produced by the LHC experiments will for the first time be made openly available to all. It is expected that these data will be of high value for the research community, and also be used for education purposes.

”Launching the CERN Open Data Portal is an important step for our Organization. Data from the LHC programme are among the most precious assets of the LHC experiments, that today we start sharing openly with the world. We hope these open data will support and inspire the global research community, including students and citizen scientists,” said CERN Director General Rolf Heuer.

The principle of openness is enshrined in CERN’s founding Convention, and all LHC publications have been published Open Access, free for all to read and re-use. Widening the scope, the LHC collaborations recently approved Open Data policies and will release collision data over the coming years.

The first high-level and analysable collision data openly released come from the CMS experiment and were originally collected in 2010 during the first LHC run. This data set is now publicly available on the CERN Open Data Portal. Open source software to read and analyse the data is also available, together with the corresponding documentation. The CMS collaboration is committed to releasing its data three years after collection, after they have been thoroughly studied by the collaboration.

“This is all new and we are curious to see how the data will be re-used,” said CMS data preservation coordinator Kati Lassila-Perini. “We’ve prepared tools and examples of different levels of complexity from simplified analysis to ready-to-use online applications. We hope these examples will stimulate the creativity of external users.”

 The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b'- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b'- region plotted with a finer binning. Credit: CERN
The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b’- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b’- region plotted with a finer binning.
Credit: CERN

In parallel, the CERN Open Data Portal gives access to additional event data sets from the ALICE, ATLAS, CMS and LHCb collaborations, which have been specifically prepared for educational purposes, such as the international masterclasses in particle physics2 benefiting over ten thousand high-school students every year. These resources are accompanied by visualisation tools.

“Our own data policy foresees data preservation and its sharing. We have seen that students are fascinated by being able to analyse LHC data in the past and so, we are very happy to take the first steps and make available some selected data for education” said Silvia Amerio, data preservation coordinator of the LHCb experiment.

“The development of this Open Data Portal represents a first milestone in our mission to serve our users in preserving and sharing their research materials. It will ensure that the data and tools can be accessed and used, now and in the future,” said Tim Smith from CERN’s IT Department.

All data on OpenData.cern.ch are shared under a Creative Commons CC03 public domain dedication; data and software are assigned unique DOI identifiers to make them citable in scientific articles; and software is released under open source licenses. The CERN Open Data Portal is built on the open-source Invenio Digital Library software, which powers other CERN Open Science tools and initiatives.

Further information:

Open data portal

Open data policies

CMS Open Data

 

Footnote(s):

1. CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have Observer Status.

2. http://www.physicsmasterclasses.org(link is external)

3. http://creativecommons.org/publicdomain/zero/1.0/

The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b'- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b'- region plotted with a finer binning.
Credit: CERN

LHCb experiment observes two new baryon particles never seen before

Geneva 19 November 2014. Today the collaboration for the LHCb experiment at CERN1’s Large Hadron Collider announced the discovery of two new particles in the baryon family. The particles, known as the Xi_b’- and Xi_b*-, were predicted to exist by the quark model but had never been seen before. A related particle, the Xi_b*0, was found by the CMS experiment at CERN in 2012. The LHCb collaboration submitted a paper reporting the finding to Physical Review Letters.

Like the well-known protons that the LHC accelerates, the new particles are baryons made from three quarks bound together by the strong force. The types of quarks are different, though: the new X_ib particles both contain one beauty (b), one strange (s), and one down (d) quark. Thanks to the heavyweight b quarks, they are more than six times as massive as the proton. But the particles are more than just the sum of their parts: their mass also depends on how they are configured. Each of the quarks has an attribute called “spin”. In the Xi_b’- state, the spins of the two lighter quarks point in the opposite direction to the b quark, whereas in the Xi_b*- state they are aligned. This difference makes the Xi_b*a little heavier.

“Nature was kind and gave us two particles for the price of one,” said Matthew Charles of the CNRS’s LPNHE laboratory at Paris VI University. “The Xi_b’is very close in mass to the sum of its decay products: if it had been just a little lighter, we wouldn’t have seen it at all using the decay signature that we were looking for.”

 The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b'- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b'- region plotted with a finer binning. Credit: CERN
The mass difference spectrum: the LHCb result shows strong evidence of the existence of two new particles the Xi_b’- (first peak) and Xi_b*- (second peak), with the very high-level confidence of 10 sigma. The black points are the signal sample and the hatched red histogram is a control sample. The blue curve represents a model including the two new particles, fitted to the data. Delta_m is the difference between the mass of the Xi_b0 pi- pair and the sum of the individual masses of the Xi_b0 and pi-.. INSET: Detail of the Xi_b’- region plotted with a finer binning.
Credit: CERN

“This is a very exciting result. Thanks to LHCb’s excellent hadron identification, which is unique among the LHC experiments, we were able to separate a very clean and strong signal from the background,”said Steven Blusk from Syracuse University in New York. “It demonstrates once again the sensitivity and how precise the LHCb detector is.”

As well as the masses of these particles, the research team studied their relative production rates, their widths – a measure of how unstable they are – and other details of their decays. The results match up with predictions based on the theory of Quantum Chromodynamics (QCD).

QCD is part of the Standard Model of particle physics, the theory that describes the fundamental particles of matter, how they interact and the forces between them. Testing QCD at high precision is a key to refine our understanding of quark dynamics, models of which are tremendously difficult to calculate.

“If we want to find new physics beyond the Standard Model, we need first to have a sharp picture,” said LHCb’s physics coordinator Patrick Koppenburg from Nikhef Institute in Amsterdam. “Such high precision studies will help us to differentiate between Standard Model effects and anything new or unexpected in the future.”

The measurements were made with the data taken at the LHC during 2011-2012. The LHC is currently being prepared – after its first long shutdown – to operate at higher energies and with more intense beams. It is scheduled to restart by spring 2015.

Further information

Link to the paper on Arxiv: http://arxiv.org/abs/1411.4849(link is external)
More about the result on LHCb’s collaboration website: http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html#StrBeaBa
Observation of a new Xi_b*0 beauty particle, on CMS’ collaboration website:http://cms.web.cern.ch/news/observation-new-xib0-beauty-particle

Footnote(s)

1. CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have Observer Status.

Source: CERN

This artist’s impression depicts the formation of a galaxy cluster in the early Universe. The galaxies are vigorously forming new stars and interacting with each other. Such a scene closely resembles the Spiderweb Galaxy (formally known as MRC 1138-262) and its surroundings, which is one of the best-studied protoclusters.

Credit:

ESO/M. Kornmesser

Syracuse Physicists Closer to Understanding Balance of Matter, Antimatter

Physicists in the College of Arts and Sciences have made important discoveries regarding Bs meson particles—something that may explain why the universe contains more matter than antimatter. Distinguished Professor Sheldon Stone and his colleagues recently announced their findings at a workshop at CERN in Geneva, Switzerland. Titled “Implications of LHCb Measurements and Their Future Prospects,” the workshop enabled him and other members of the Large Hadron Collider beauty (LHCb) Collaboration to share recent data results. The LHCb Collaboration is a multinational experiment that seeks to explore what happened after the Big Bang, causing matter to survive and flourish in the Universe. LHCb is an international experiment, based at CERN, involving more than 800 scientists and engineers from all over the world. At CERN, Stone heads up a team of 15 physicists from Syracuse. “Many international experiments are interested in the Bs meson because it oscillates between a matter particle and an antimatter particle,” says Stone, who heads up Syracuse’s High-Energy Physics Group. “Understanding its properties may shed light on charge-parity [CP] violation, which refers to the balance of matter and antimatter in the universe and is one of the biggest challenges of particle physics.” Scientists believe that, 14 billion years ago, energy coalesced to form equal quantities of matter and antimatter. As the universe cooled and expanded, its composition changed. Antimatter all but disappeared after the Big Bang (approximately 3.8 billion years ago), leaving behind matter to create everything from stars and galaxies to life on Earth. “Something must have happened to cause extra CP violation and, thus, form the universe as we know it,” Stone says. He thinks part of the answer lies in the Bs meson, which contains an antiquark and a strange quark and is bound together by a strong interaction. (A quark is a hard, point-like object found inside a proton and neutron that forms the nucleus of an atom.) Enter CERN, a European research organization that operates the world’s largest particle physics laboratory. In Geneva, Stone and his research team—which includes Liming Zhang, a former Syracuse research associate who is now a professor at Tsinghua University in Beijing, China—have studied two landmark experiments that took place at Fermilab, a high-energy physics laboratory near Chicago, in 2009. The experiments involved the Collider Detector at Fermilab (CDF) and the DZero (D0), four-story detectors that were part of Fermilab’s now-defunct Tevatron, then one of the world’s highest-energy particle accelerators. “Results from D0 and CDF showed that the matter-antimatter oscillations of the Bs meson deviated from the standard model of physics, but the uncertainties of their results were too high to make any solid conclusions,” Stone says. He and Zhang had no choice but to devise a technique allowing for more precise measurements of Bs mesons. Their new result shows that the difference in oscillations between the Bs and anti-Bs meson is just as the standard model has predicted. Stone says the new measurement dramatically restricts the realms where new physics could be hiding, forcing physicists to expand their searches into other areas. “Everyone knows there is new physics. We just need to perform more sensitive analyses to sniff it out,” he adds.

Source: Syracuse University

The Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile has taken this beautiful image, dappled with blue stars, of one of the most star-rich open clusters currently known — Messier 11, also known as NGC 6705 or the Wild Duck Cluster. Credit: ESO

Discovery of new subatomic particle sheds light on fundamental force of nature

The discovery of a new particle will “transform our understanding” of the fundamental force of nature that binds the nuclei of atoms, researchers argue.

he Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile has taken this beautiful image, dappled with blue stars, of one of the most star-rich open clusters currently known — Messier 11, also known as NGC 6705 or the Wild Duck Cluster. Credit: ESO
Along with gravity, the electromagnetic interaction and weak nuclear force, strong-interactions are one of four fundamental forces. Lead scientist Professor Tim Gershon, from The University of Warwick’s Department of Physics, explains:
“Gravity describes the universe on a large scale from galaxies to Newton’s falling apple, whilst the electromagnetic interaction is responsible for binding molecules together and also for holding electrons in orbit around an atom’s nucleus.”
Image Credit: ESO

Led by scientists from the University of Warwick, the discovery of the new particle will help provide greater understanding of the strong interaction, the fundamental force of nature found within the protons of an atom’s nucleus.

Named Ds3*(2860)ˉ, the particle, a new type of meson,[1] was discovered by analysing data collected with the LHCb detector at CERN’s Large Hadron Collider (LHC)[2]. The LHCb experiment, which is run by a large international collaboration, is designed to study the properties of particles containing beauty and charm quarks and has unique capability for this kind of discovery.

The new particle is bound together in a similar way to protons. Due to this similarity, the Warwick researchers argue that scientists will now be able to study the particle to further understand strong interactions.

Along with gravity, the electromagnetic interaction and weak nuclear force, strong-interactions are one of four fundamental forces. Lead scientist Professor Tim Gershon, from The University of Warwick’s Department of Physics, explains:

“Gravity describes the universe on a large scale from galaxies to Newton’s falling apple, whilst the electromagnetic interaction is responsible for binding molecules together and also for holding electrons in orbit around an atom’s nucleus.”

The strong interaction is the force that binds quarks, the subatomic particles that form protons within atoms, together. It is so strong that the binding energy of the proton gives a much larger contribution to the mass, through Einstein’s equation E = mc2, than the quarks themselves.[3]

Due in part to the forces’ relative simplicity, scientists have previously been able to solve the equations behind gravity and electromagnetic interactions, but the strength of the strong interaction makes it impossible to solve the equations in the same way.

“Calculations of strong interactions are done with a computationally intensive technique called Lattice QCD,” says Professor Gershon. “In order to validate these calculations it is essential to be able to compare predictions to experiments. The new particle is ideal for this purpose because it is the first known that both contains a charm quark and has spin 3.”

There are six quarks known to physicists; Up, Down, Strange, Charm, Beauty and Top. Protons and neutrons are composed of up and down quarks, but particles produced in accelerators such as the LHC can contain the unstable heavier quarks. In addition, some of these particles have higher spin values than the naturally occurring stable particles.

“Because the Ds3*(2860)ˉ particle contains a heavy charm quark it is easier for theorists to calculate its properties. And because it has spin 3, there can be no ambiguity about what the particle is,” adds Professor Gershon. “Therefore it provides a benchmark for future theoretical calculations. Improvements in these calculations will transform our understanding of how nuclei are bound together.”

Spin is one of the labels used by physicists to distinguish between particles. It is a concept that arises in quantum mechanics that can be thought of as being similar to angular momentum: in this sense higher spin corresponds to the quarks orbiting each other faster than those with a lower spin.

Warwick Ph.D. student Daniel Craik, who worked on the study, adds “Perhaps the most exciting part of this new result is that it could be the first of many similar discoveries with LHC data. Whether we can use the same technique, as employed with our research into Ds3*(2860)ˉ, to also improve our understanding of the weak interaction is a key question raised by this discovery. If so, this could help to answer one of the biggest mysteries in physics: why there is more matter than antimatter in the Universe.”

The results are detailed in two papers that will be published in the next editions of the journals Physical Review Letters and Physical Review D. Both papers have been given the accolade of being selected as Editors’ Suggestions.

[1] The Ds3*(2860)ˉ particle is a meson that contains a charm anti-quark and a strange quark. The subscript 3 denotes that it has spin 3, while the number 2860 in parentheses is the mass of the particle in the units of MeV/c2 that are favoured by particle physicists. The value of 2860 MeV/c2 corresponds to approximately 3 times the mass of the proton.

[2] The particle was discovered in the decay chain Bs0D0Kπ+ , where the Bs0, D0, K and π+ mesons contain respectively a bottom anti-quark and a strange quark, a charm anti-quark and an up quark, an up anti-quark and a strange quark, and a down anti-quark and an up quark. The Ds3*(2860)ˉ particle is observed as a peak in the mass of combinations of the D0 and K mesons. The distributions of the angles between the D0, K and π+ particles allow the spin of the Ds3*(2860)ˉ meson to be unambiguously determined.

[3] Quarks are bound by the strong interaction into one of two types of particles: baryons, such as the proton, are composed of three quarks; mesons are composed of one quark and one anti-quark, where an anti-quark is the antimatter version of a quark.

The results are detailed in papers titled:

- The LHCb experiment is one of the four main experiments at the CERN Large Hadron Collider, and is set up to explore what happened after the Big Bang that allowed matter to survive and build the Universe we inhabit today. The LHCb collaboration comprises about 700 physicists from 67 institutes in 17 countries.

- CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have Observer Status.

- The UK Science and Technology Facilities Council [www.stfc.ac.uk] coordinates and manages the UK’s involvement and subscription with CERN.

- The University of Warwick researchers who led this work are funded by the Science and Technology Facilities Council and the European Research Council.

- Further information on these results can be found in the LHCb collaboration public web page (http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html#TwoSt) and the CERN Courier Sept. 2014 edition (http://cerncourier.com/cws/article/cern/58193)

Source: Warwick University

Figure 1 (left) Exclusion limits for production of Higgsino production as a function of Higgsino mass and branching fraction. (right) Most sensitive search channel as a function of Higgsino mass and branching fraction. Credit: CERN

Recent results in the search for supersymmetry : CERN CMS

By Frank Wuerthwein, Keith Ulmer and Guillelmo Gomez Ceballos.


Among the leading candidates to describe physics beyond the standard model of particle physics is Supersymmetry, a new symmetry that posits the existence of a partner particle for each known particle in the standard model. Supersymmetry, or “SUSY” as it has come to be known, may help explain the nature of dark matter and the large difference in strength between the fundamental forces of nature. Each year, new experimental results and theoretical developments are reported in the “SUSY” conference series, with the 2014 edition (SUSY2014) happening this week in Manchester, England[1].

Figure 1 (left) Exclusion limits for production of Higgsino production as a function of Higgsino mass and branching fraction. (right) Most sensitive search channel as a function of Higgsino mass and branching fraction. Credit: CERN
Figure 1 (left) Exclusion limits for production of Higgsino production as a function of Higgsino mass and branching fraction. (right) Most sensitive search channel as a function of Higgsino mass and branching fraction. Credit: CERN

Experimental evidence for SUSY has been sought for many years at multiple colliders, including a vast array of search results from the CMS experiment at the Large Hadron Collider at CERN. With data from Run 1 of the LHC collected through the end of 2012, the full set of results thus far has not revealed any striking signs of physics beyond the standard model [2]. New searches presented at SUSY2014 have begun to probe increasingly complicated potential decay chains and to combine multiple searches to access more challenging new physics scenarios. Below we highlight some of the most recent results first presented this summer at SUSY14 and ICHEP 2014 [3].

Figure 2: Exclusion limits versus gluino and neutralino masses for a variety of gluino decay branching fractions from the “razor” search. Credit: CERN
Figure 2: Exclusion limits versus gluino and neutralino masses for a variety of gluino decay branching fractions from the “razor” search. Credit: CERN

Search for new physics in the final states hh, Zh, and ZZ plus MET

After its discovery only two years ago, the Higgs boson is already a powerful tool in the search for new physics. Earlier this year, CMS submitted for publication [4] a set of searches for associate production of W, Higgs, and missing transverse energy (“MET”, indicative of particles escaping the detector). At ICHEP this summer, CMS presented the first combined searches for hh, Zh, and ZZ plus MET. No excess above standard model backgrounds is observed. Figure 1 shows the interpretation of the results in terms of limits on higgsino pair production as a function of the higgsino mass and decay branching fraction. Within the framework of Gauge Mediated Supersymmetry Breaking (GMSB), the neutral higgsino decays to a gravitino and either a higgs or Z boson. The left plot in Figure 1 shows that CMS excludes higgsino production up to ~ 300GeV when the higgsino decays at equal rate to either of these two decays. The right plot in Figure 1 indicates that four different final states dominate the sensitivity in different parts of the 2D parameter space, clearly demonstrating that searches for new physics with one or two higgs bosons in the final state benefit greatly from combining many different decay channels.

Figure 3: Dilepton invariant mass distribution for “same flavor” events, compared to the background prediction from “opposite flavor” events. Credit:CERN
Figure 3: Dilepton invariant mass distribution for “same flavor” events, compared to the background prediction from “opposite flavor” events. Credit:CERN

Search for gluino pair production via the decays to top pairs, bottom pairs, or top and bottom plus MET

Up to now, CMS searches for gluino pair production inspired by “natural SUSY” (i.e. SUSY in which the masses of the SUSY partners are not much higher than those of the Higgs boson) have focused on final states with either four top or four b-quarks plus MET. In contrast, theoretically any combination of MET plus 4 quarks, top or bottom, is well justified. At ICHEP, CMS presented the first complete exploration of sensitivity across the full set of possible final states and branching fractions. Figure 2 shows the corresponding exclusion curves in the gluino vs neutralino mass plane. This search employs the so-called “razor” variables, and its sensitivity is dominated by all-hadronic final states. The more top quarks there are in the final state for a given gluino mass, the less momentum is left for all the decay products, and the harder it is thus to distinguish signal from background. Accordingly, the sensitivity decreases as the number of top quarks per event increases.

Figure 4: MSSMvsSM limit in the MSSM mmod+h scenario. At each mA - tanβpoint a Hypothesis test is performed testing the MSSM (A+H+h+BKG) hypothesis against the SM (hSM+BKG) hypothesis. Credit: CERN
Figure 4: MSSMvsSM limit in the MSSM mmod+h scenario. At each mA – tanβpoint a Hypothesis test is performed testing the MSSM (A+H+h+BKG) hypothesis against the SM (hSM+BKG) hypothesis. Credit: CERN

Searching for SUSY with an “Edge”

The dilepton invariant mass distribution for leptons from the decays χ20 to l+l- χ10, or similar decays via a slepton as an intermediate state, display the striking feature of a kinematic “edge” [5, 6]. As these decays conserve lepton flavor, this edge is present only in same-flavor events, i.e. ee and μμ, and is completely absent in the “opposite flavor” lepton sample, i.e. eμ events. In contrast, backgrounds for which each of the two leptons come from a different W decay, e.g. top pairs, WW, etc., will have identical dilepton distributions for same and opposite flavor. Thus, the eμ sample in data provides a perfect model of the background dilepton mass distribution – modulo effects from the trigger and lepton reconstruction. The kinematic edge is a sufficiently striking signature to reveal new physics even at relatively modest hadronic activity, HT and MET, i.e. in the presence of sizeable top and Z backgrounds.

CMS presented a search for such an “edge” in dilepton events with jets and MET at SUSY2014 using the full 8TeV data sample [7]. Figure 3 overlays the dilepton mass distribution in ee plus μμ (data points), with the corresponding one from eμ (pink histogram). The blue shaded region depicts the systematic error envelope for the background prediction. A small excess is visible below the Z peak. A signal region of 20GeV < mll < 70GeV was chosen before data taking. Within this region, 860 events are observed with an expected standard model background yield of 730 ± 40. The small excess is consistent with a 2.6 sigma fluctuation of the standard model background. For more details see [8].

Search for additional neutral MSSM Higgs bosons in the H→ττ decay channel

Another highlight among the CMS results presented at the SUSY2014 conference is the search for additional neutral Higgs bosons decaying to τ leptons, which is the most promising channel to search for such Higgs bosons in the context of the minimal SUSY extension of the standard model, the MSSM. Following the release of a preliminary result based on the full data set of the 2011/2012 data taking period [8], additional results based on a new interpretation of the data have been presented at this conference for the first time [9]. While the data selection has not changed, extensive work has set the ground for a new interpretation of the data in the context of modern benchmark models. In particular, the new models take into account the presence of the recently discovered Higgs boson with a mass of 125 GeV, as proposed in [10]. Also for the first time the model-dependent exclusion contours as a function of the mass of the CP-odd Higgs boson, A, and the ratio of the vacuum expectation values of the two SUSY Higgs doublets, tanβ, have been derived, taking the presence of the newly discovered Higgs boson properly into account in the test statistic. As recently demonstrated by CMS [11], all observations of the new boson are so far compatible with the SM expectation within ~10% accuracy, which justifies the standard model hypothesis to be the better choice for the test statistic. The hypothesis test now becomes a search based on a model with three Higgs bosons compared against the standard model with only one Higgs boson. Traditional limits, based on the test statistic excluding the Higgs boson from the standard model hypothesis have also been made public on the CMS web-pages [12]. Also made available to the public is an extended database of results based on a model-independent single-resonance search model, which will be extremely valuable to theorists engaged in model building. Figure 1 shows the exclusion contour in a modified mh,max scenario, also referred to as mh,mod+ exploiting the new statistical treatment for the statistical inference.

By Frank Wuerthwein, Keith Ulmer and Guillelmo Gomez Ceballos.


[1] http://www.susy2014.manchester.ac.uk

[2] https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSUS

[3] http://ichep2014.es

[4] https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSUS13006

[5] http://cds.cern.ch/record/1194507/files/SUS-09-002-pas.pdf

[6] https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSUS11011

[7] https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSUS12019

[8] CMS Collaboration, “Search for Neutral MSSM Higgs Bosons Decaying to Tau Pairs in pp Collisions”, (2013), CMS-PAS-HIG-13-021.

[9] CMS Collaboration, “Search for Neutral MSSM Higgs Bosons Decaying to Tau Pairs in pp Collisions”, to be submitted to JHEP.

[10] M. S. Carena et al, “MSSM Higgs boson searches at the Tevatron and at the LHC: Impact of different benchmark scenarios” Eur. Phy. J C 73, 2552 (2013) (arXiv:hep-ph/0511023).

[11] CMS Collaboration, “Precise determination of the mass of the Higgs boson and studies of the compatibility of its couplings with the standard model”, (2014), CMS-PAS-HIG-14-009.

[12] https://indico.hep.manchester.ac.uk/contributionDisplay.py?contribId=288….

Source: CERN CMS

ginipkcnin

Science, Economy and Peace: A study focusing Pakistan

Syed Faisal ur Rahman


 

 Abstract: A key difference between the first world and the third world is their progress in the fields of science and technology. Pakistan is mainly known as an agricultural economy but agriculture sector does not contribute much in shaping the modern global economy. We will analyze how science and technology helped in improving the lives of people but also will see its role in the economic development of countries. In the age of conflicts, war and economic rivalry, it is often hard to find common grounds for humanity to proceed for common goals. Fortunately, some big science projects have proved to be a beacon of hope for humanity in pursuing a better peaceful and prosperous future for this world.We will give an overview of some of the projects pursued by countries who are normally rivals at military and economic fronts, but for pursuing science goals they have to join hands, giving a better hope for peace and economic development. We will also see how Pakistan can learn from the experiences of other countries and regions to build a better future for it’s people.

 


 

Introduction

Last century saw enormous developments in the field of science and technology, which also helped countries to rapidly develop their potential in industry, medical sciences, defense, space and many other sectors. Countries which made science and technology research and education as priority areas emerged as stronger nations as compared to those who merely relied on agriculture and the abundance of natural resources.

We can also see that big science projects, involving one or more than one country, have served our society through spin-off technologies, human resource development, boosting up economic activity and cooperation. Also, we will study the role of some big science projects in promoting peace and stability in the world.

Global Economy and Pakistan

According to Central Intelligence Agency (CIA) world factbook public data [14], global economy has a size of 71.3 trillion dollars if we look at Gross Domestic Product (GDP) based on official exchange rate and 83.12 trillion dollars based on GDP purchasing power parity (PPP).

The contribution of different sectors based on CIA world fact book 2012 estimates, is as:

Agriculture- 5.9%

Industry -30.2%

Services- 63.9%

Pakistan which comprises of ~2.5-2.7 (2011 World Bank Data) percent of world population, only has 230.5 billion dollars GDP (official exchange rate) and 514.6 billion dollars GDP (PPP) which makes it around 0.32 % of the world economy based on GDP (official exchange rate) and 0.62% based on GDP(PPP). This shows a serious gap in income scales of some of the developed countries of the world and a relatively poor economy like Pakistan. This high population and low GDP mean less money available to individuals living in the country. GDP per capita (PPP) of the world is 12,400 dollars based on CIA world factbook 2012 estimates and for Pakistan the figure is 2,900 dollars.

Pakistan is also relatively more dependent on the agricultural sector. Pakistan’s labor composition is estimated in 2012 CIA world fact book as:

Agriculture- 20.1%

Industry- 25.5%

Services- 54.4%

If we look at the labor distribution, then according to 2007 estimates, Pakistan’s ~45% population is involved in the agricultural sector, which is more than industry (~21%) and services (~34%).

 Science, Technology and Global Economy

Below is plot of World Bank 2011 data [13] for countries with highest Gross National Income (GNI) per capita:

gnipercapita

Fig. 1: GNI per capita for 2011 based on World Bank Data

If we look at figure 1 then we can clearly see that most countries in top 20 GNI are knowledge based economies and some represent natural resource or energy based economies. In comparison with these economies, Pakistan’s GNI is 1,120 dollars based on the same criteria.

A more direct comparison can be given between GDP and science output is the table below showing top scientific and technical journal producers and their GDP rankings:

Rank(based on column 3) Country Scientific and Technical Journal Articles (2009, World Bank Data)[13] GDP Ranking ( based on 2011, World Bank Data) Human Development Index(HDI, based on 2012 UNDP Data) [11] Category
1 United States 208,601 1 Very High
2 China 74,019 2 Medium
3 Japan 49,627 3 Very High
4 United Kingdom 45,649 7 Very High
5 Germany 45,003 4 Very High
6 France 31,748 5 Very High
7 Canada 29,017 10 Very High
8 Italy 26,755 7 Very High
9 South Korea 22,271 14 Very High
10 Spain 21,543 11 Very High
11 India 19,917 8 Medium
12 Australia 18,923 12 Very High
13 Netherlands 14,866 16 Very High
14 Russia 14,016 9 High
15 Brazil 12,306 6 High
16 Sweden 9,478 20 Very High
17 Switzerland 9,469 18 Very High
18 Turkey 8,301 17 High
19 Poland 7,355 21 Very High
20 Belgium 7,218 22 Very High
46 Pakistan 1,043 45 Low

Table 1: Pakistan and the top 20 Sci-tech journal articles producing countries and their GDP rankings (based on the World Bank data). Also we have presented the Human Development Index (HDI) categories of these countries based on the 2012 United Nations Development Program’s HDI data.

Figures in table 1, clearly shows some relation between scientific output and the size of the overall economy. There are few exceptions like Saudi Arabia, which makes regularly into the top 20 economies and is not one of the top producers of scientific and technical journal articles. We can find such inconsistencies as there is more than one factor which contributes to the size of the economy like exploitation of energy resources, minerals, large size of populations and various other factors.

Also we can see that most sci-tech journal articles producing countries are in very high HDI countries with 3 in high and 2 in medium categories. We can see two medium category countries are two of the largest populations on earth i.e. China and India. HDI of a country depends on the access to health, income, access to education and living standard of the citizens of that country. This indicator provides a more realistic picture as compared to GDP for measuring quality of life as countries with large populations like China and India can have high GDP despite lower average income or can have a higher number of sci-tech publications or output despite not doing well in per person averages. In comparison to these countries, Pakistan is in the low HDI category which shows the low quality of life for the citizens of Pakistan.

Pakistan and comparison with India and China

We further narrow our comparison with countries having similar regional and economic history. For this we select India and China. India and China reside in the same region as Pakistan and got independence in the same time period of the late 40s. China has the largest population in the world and India has the second largest population having relatively high population density.

If we look at the historical comparisons after the separation of the East Pakistan from the federation, we can see we were well ahead of both China and India, in terms of GNI per capita and the economic freedom, for a good part of our history. Apart, from being relatively free market economy, Pakistan also did well in the development of techno-industry. Almost all major scientific organizations related to heavy industries, space, nuclear, agricultural and other areas developed in earlier decades of Pakistan. In later years, Pakistan was left behind in development by the two countries. One of the main reasons behind this is Pakistan’s lack of interest in the science and technology sectors and the inability to keep up with the pace of science and technology development in India and China. We can see historical GNI comparisons between Pakistan, China and India.

China adopted a focused techno-industrial development approach. According to Campbell, 2013 [3] paper, China developed its industrial base on Soviet lines till 1959 focusing on heavy industries. After that, till 1976 ideological domination of economic projects and economy didn’t progress much.  Then China adopted a more independent technology research policy with a relatively liberal economic agenda and in 2001 with further Chinese shift towards a market economy from a controlled economy, these policies started to give results as the involvement of private sector in such projects ensured the translation of technology research into commercial success.

Similarly, India focused strongly on science and technology from its early days and also started to initially focus on heavy industries on Soviet lines. Later, especially in early 1990s, with the liberalization of the economy and the policy shift towards more market economy, India started to promote small technology based industries. A good focus of India was on software industry which not only helped India in bringing more export revenues, but also helped improve corporate governance in India (Arora et al, 2002)[1]. This led to more productivity in many industries of India and with gradual shifts towards a market economy India also saw rapid economic growth.

Fig. 2: GNI comparison between Pakistan, China and India (World Bank 2013 Data)

Collaboration in Science and World Peace

Apart from economic development, science projects have also contributed in promoting peace and collaboration among many countries including many rival countries. The lead in promoting scientific collaboration for peace was taken by Europe. After the World War II, Europe learned to promote economic cooperation instead of unnecessary rivalry. This cooperation in economic areas grew further and expanded in other areas like science and technology. Launch of The European Organization for Nuclear Research, or CERN[4] in 1954 was a huge step in promoting scientific collaboration among European countries in post-World War II scenario. This spirit continued even in Cold War days (Gillies, 2011) [6] as the idea of exploring the nature of matter and energy proved to be bigger than the prejudices and blind nationalism.

This spirit continued further in other big sciences and we now see countries like USA, China, Russia, UK and others doing collaborations in space sciences, particle physics, astronomy, medicine and many other areas. Some of the examples in this regard are Square Kilometer Array (SKA), Synchrotron-Light for Experimental Science and Applications in the Middle East (SESAME), Search for Extra-terrestrial Intelligence (SETI), International Space Station (ISS) and other projects are forwarding such spirit.

Apart from this many countries are involved in other collaborative projects as well. These projects are always welcomed in civil society and the scientific community as a way to promote peace.

Pakistan is also involved in some of these projects like CERN and SESAME. Pakistan’s collaboration with CERN formally started in past two decades. Pakistan’s connection with CERN is even older than Pakistan’s formal entry in this collaboration. This connection was established through Pakistan’s Nobel Laureate, Dr. Abdus Salam. Still a lot is needed to be done by Pakistan to get the best out of these collaborations with CERN.

In SESAME, Pakistan played a key role by becoming a founding member. The idea is a brain child of Dr. Abdus Salam and Middle East based MESC (Middle East Scientific Cooperation) group headed by Sergio Fubini, a theoretician at CERN, who aspired for a synchrotron radiation source in the Middle East (Historical highlights, SESAME website) [10]. SESAME shares the same spirit of science for peace with CERN as it is helping to bridge the gap between historically rival nations and in improving people to people relations between countries like Pakistan, Iran, Israel, Palestinian Authority, Egypt, Turkey and others who are often involved in heated conflicts in the region. The project was shown full support by 45 Nobel Laureates in a joint declaration which also demanded friends of science and peace to support the project (Declaration, PETRA VI meeting, June 2008) [5].

Pakistan is still behind many countries of the world in space sciences despite being among the first few countries to launch a space rocket in the 1960s. Similarly, Pakistan has not played a significant role in any significant collaboration related to the promotion of astronomy. Our neighboring countries are playing key roles in projects like SKA (skatelescope.org, participating countries) [8] and are also expected to join ISS in the future (Spacenews, 2010) [9].

Big Science and Economic Development

Big science projects have not only played a crucial role in bringing peace or satisfying human curiosity to know more about the nature and origin of matter, energy and the universe, but the path to achieve such scale of science has led to many spin-off technology developments.

Development of World Wide Web (WWW) is a result of data sharing architecture designed for CERN (webfoundation.org, history of the web) [7], Wi-Fi is a result of CSIRO’s efforts to develop better techniques for radio astronomy (csiro.au, outcomes)[12], research in radio astronomy has also played a key role in developing techniques for locating cellular telephones, location for faulty transmitters (Bout, 1999)[2] and various other technologies.

The key here is to understand the importance of basic and fundamental sciences, and understanding the importance of adopting the right strategy for using the resulting science and technologies for economic and social development.

 Pakistan and Suggestions to Develop Science and Technology for Economic Development

The purpose of presenting various examples, data and figures is to show the necessity of developing a solid foundation for science and technology in Pakistan. We are a country with significant potential in minerals, energy and agricultural resources. Also, we have developed some advanced technology base in the defense sector. We also have a small but energetic Information Technology industry, which is growing well despite difficulties due to law and order situation, and electricity crisis in the country.

Below are some of the steps we can take to promote science and technology in Pakistan and then use it for developing Pakistan’s economy.

a) We need to improve basic science education in the country. The school level curriculum is way behind as compared to other parts of the world. We need to produce students who can think big and even if they do not pursue science as their career, they should be at least educated enough to appreciate the importance of fundamental research. Even if students end up pursuing management studies or end up as key decision makers in government or private sector offices then they will be better equipped to realize the importance of science and technology research in the progress of our country or to come up with business idea which will exploit scientific knowledge.

b) We need to promote research and development in the universities by encouraging industry-academia linkages by providing tax incentives for industries involved in promoting research and development in the universities of Pakistan.

c) We need to share the technology base developed in defense sector with the private sector so that it can be used for peaceful commercialization of technology.

d) We need to give tax and reward incentives to the private sector for contributing in fundamental sciences.

e) We need to promote collaboration between universities and strategic national organizations like SUPARCO and NESCOM.

f) The most important thing which is needed to be done is to give the leading role in policy making to the civilian scientists with sound academic and research background. Currently, institutions like SUPARCO, NESCOM and other institutions are under the direct or indirect control of military personnel who usually do not have enough academic and research background to make the right decisions and set the right priorities in the key areas of science and technology.

g) Another thing lacking in Pakistan is active inter-university and intra-university collaboration for science projects related to interdisciplinary sciences.

h) We also need to give priority to the science and technology collaboration in academic and fundamental research areas when planning our foreign policy. Currently, our foreign policy is security focused with no serious efforts to strengthen academic ties with other countries. Our embassies are needed to be run by people who understand how important it is to interact with the academia of the country they are serving in and how important it is to help our universities in making right relationships in foreign countries for scientific research. This will again be dependent on how good we will do in producing non-science graduates who understand the importance of science and technologies as most foreign office employees come from the arts departments, the business schools etc.

i) We finally need to start playing an active role in major areas of science and technology like particle   physics, astronomy, high performance computing, quantum computing, nano-technology and other areas where we have a potential to go ahead but lacking any serious progress due to lack of proper policy making and interest.

We also need to identify our strengths and weaknesses in various areas of technology and divide our science and technology base in:

a)      Commercial

In this category we can place technologies like information & communication, agricultural, pharmaceutical etc.

b)      Defense

Pakistan has done a significant investment over the past few decades in the development of nuclear, missile, fighter jets and other technologies. We can use these technologies for commercial purposes like producing energy or developing civil aeronautical industry.

c)       Strategic

Not all science and technology research produces immediate results but, their long term impact can be seen in other developed countries and some of them are mentioned above. In this category we can place big sciences like space, radio astronomy and high energy physics or even areas like quantum computing, geophysics etc.

d)      Fundamental or Basic

Fundamental or basic sciences help in creating the grounds for developments in other area mentioned previously. Physics is considered as the most fundamental science and in relative broader terms special sciences like chemistry and biology are also often made part of this category. In more liberal definitions, people also include mathematics, statistics and economics in this area as well. We need to improve research in this area and also we need to improve the teaching quality of these subjects in primary, secondary, higher secondary and tertiary level education systems.

This categorization will help Pakistan in better prioritizing the areas based on need and capacity.

Conclusions

We discussed the importance of science and technology in the economic development. We also presented a comparison between Pakistan and other countries, including neighboring China and India. We also discussed the role of science and technology in promoting peace and collaboration. We also discussed how big sciences can contribute to the economy through spin-off technologies. In the end, we also discussed some  suggestions for developing science and technology in Pakistan.

References

  1. Arora A. and Athreye A.,2002. The Software Industry and India’s Economic Development. Information Economics and Policy 14 (2002) 253-273.
  2. Bout P. V., April, 1999. Recent Examples of Technology Fostered by Radio Astronomy (Document).
  3.  Campbell J.R.,2013. Becoming a Techno-Industrial Power: Chinese Science and Technology Policy. Issues in Technology Innovation 23 (2013).
  4. CERN official website – http://home.web.cern.ch/
  5. Ely Wiesel Foundation Declaration, June, 2008. Declaration accepted by the Plenary Meeting of the Nobel Laureates at the PETRA IV Meeting on 19 June 2008 and released by Ely Wiesel Foundation.
  6. Gillies J., 2011, CERN can be model for global co-operation, http://www.publicserviceeurope.com/article/477/cern-can-be-model-for-global-co-operation
  7. History of web-Web foundation website http://www.webfoundation.org/vision/history-of-the-web/
  8. Participating Countries, SKA website- http://www.skatelescope.org/the-project/history-of-the-organisation/participating-countries-2/
  9. Seilding P.B. , Feb. 3, 2010, http://www.spacenews.com
  10. SESAME official website- www.sesame.org.jo
  11. United Nations Development Program (UNDP) HDI http://hdr.undp.org/en/statistics/hdi/
  12. Wireless LANs, CSIRO website- http://www.csiro.au/en/Outcomes/ICT-and-Services/People-and-businesses/wireless-LANs.aspx
  13. World Bank’s World Development Indicators (WDI) – http://data.worldbank.org/indicator
  14. World Fact Book, CIA-https://www.cia.gov/library/publications/the-world-factbook/‎