Cern News

LHC experiments see first evidence of a rare Higgs boson decay

The discovery of the Higgs boson at CERN’s Large Hadron Collider (LHC) in 2012 marked a significant milestone in particle physics. Since then, the ATLAS and CMS collaborations have been diligently investigating the properties of this unique particle and searching to establish the different ways in which it is produced and decays into other particles.

At the Large Hadron Collider Physics (LHCP) conference this week, ATLAS and CMS report how they teamed up to find the first evidence of the rare process in which the Higgs boson decays into a Z boson, the electrically neutral carrier of the weak force, and a photon, the carrier of the electromagnetic force. This Higgs boson decay could provide indirect evidence of the existence of particles beyond those predicted by the Standard Model of particle physics.

The decay of the Higgs boson into a Z boson and a photon is similar to that of a decay into two photons. In these processes, the Higgs boson does not decay directly into these pairs of particles. Instead, the decays proceed via an intermediate "loop" of “virtual” particles that pop in and out of existence and cannot be directly detected. These virtual particles could include new, as yet undiscovered particles that interact with the Higgs boson.

The Standard Model predicts that, if the Higgs boson has a mass of around 125 billion electronvolts, approximately 0.15% of Higgs bosons will decay into a Z boson and a photon. But some theories that extend the Standard Model predict a different decay rate. Measuring the decay rate therefore provides valuable insights into both physics beyond the Standard Model and the nature of the Higgs boson.

Previously, using data from proton–proton collisions at the LHC, ATLAS and CMS independently conducted extensive searches for the decay of the Higgs boson into a Z boson and a photon. Both searches used similar strategies, identifying the Z boson through its decays into pairs of electrons or muons – heavier versions of electrons. These Z boson decays occur in about 6.6% of the cases.

In these searches, collision events associated with this Higgs boson decay (the signal) would be identified as a narrow peak, over a smooth background of events, in the distribution of the combined mass of the decay products. To enhance the sensitivity to the decay, ATLAS and CMS exploited the most frequent modes in which the Higgs boson is produced and categorised events based on the characteristics of these production processes. They also used advanced machine-learning techniques to further distinguish between signal and background events.

In a new study, ATLAS and CMS have now joined forces to maximise the outcome of their search. By combining the data sets collected by both experiments during the second run of the LHC, which took place between 2015 and 2018, the collaborations have significantly increased the statistical precision and reach of their searches.

This collaborative effort resulted in the first evidence of the Higgs boson decay into a Z boson and a photon. The result has a statistical significance of 3.4 standard deviations, which is below the conventional requirement of 5 standard deviations to claim an observation. The measured signal rate is 1.9 standard deviations above the Standard Model prediction.

“Each particle has a special relationship with the Higgs boson, making the search for rare Higgs decays a high priority,” says ATLAS physics coordinator Pamela Ferrari. "Through a meticulous combination of the individual results of ATLAS and CMS, we have made a step forward towards unravelling yet another riddle of the Higgs boson."

“The existence of new particles could have very significant effects on rare Higgs decay modes,” says CMS physics coordinator Florencia Canelli. “This study is a powerful test of the Standard Model. With the ongoing third run of the LHC and the future High-Luminosity LHC, we will be able to improve the precision of this test and probe ever rarer Higgs decays.”

angerard Fri, 05/26/2023 - 09:43 Publication Date Fri, 05/26/2023 - 11:00

LHC experiments see first evidence of a rare Higgs boson decay

The discovery of the Higgs boson at CERN’s Large Hadron Collider (LHC) in 2012 marked a significant milestone in particle physics. Since then, the ATLAS and CMS collaborations have been diligently investigating the properties of this unique particle and searching to establish the different ways in which it is produced and decays into other particles.

At the Large Hadron Collider Physics (LHCP) conference this week, ATLAS and CMS report how they teamed up to find the first evidence of the rare process in which the Higgs boson decays into a Z boson, the electrically neutral carrier of the weak force, and a photon, the carrier of the electromagnetic force. This Higgs boson decay could provide indirect evidence of the existence of particles beyond those predicted by the Standard Model of particle physics.

The decay of the Higgs boson into a Z boson and a photon is similar to that of a decay into two photons. In these processes, the Higgs boson does not decay directly into these pairs of particles. Instead, the decays proceed via an intermediate "loop" of “virtual” particles that pop in and out of existence and cannot be directly detected. These virtual particles could include new, as yet undiscovered particles that interact with the Higgs boson.

The Standard Model predicts that, if the Higgs boson has a mass of around 125 billion electronvolts, approximately 0.15% of Higgs bosons will decay into a Z boson and a photon. But some theories that extend the Standard Model predict a different decay rate. Measuring the decay rate therefore provides valuable insights into both physics beyond the Standard Model and the nature of the Higgs boson.

Previously, using data from proton–proton collisions at the LHC, ATLAS and CMS independently conducted extensive searches for the decay of the Higgs boson into a Z boson and a photon. Both searches used similar strategies, identifying the Z boson through its decays into pairs of electrons or muons – heavier versions of electrons. These Z boson decays occur in about 6.6% of the cases.

In these searches, collision events associated with this Higgs boson decay (the signal) would be identified as a narrow peak, over a smooth background of events, in the distribution of the combined mass of the decay products. To enhance the sensitivity to the decay, ATLAS and CMS exploited the most frequent modes in which the Higgs boson is produced and categorised events based on the characteristics of these production processes. They also used advanced machine-learning techniques to further distinguish between signal and background events.

In a new study, ATLAS and CMS have now joined forces to maximise the outcome of their search. By combining the data sets collected by both experiments during the second run of the LHC, which took place between 2015 and 2018, the collaborations have significantly increased the statistical precision and reach of their searches.

This collaborative effort resulted in the first evidence of the Higgs boson decay into a Z boson and a photon. The result has a statistical significance of 3.4 standard deviations, which is below the conventional requirement of 5 standard deviations to claim an observation. The measured signal rate is 1.9 standard deviations above the Standard Model prediction.

“Each particle has a special relationship with the Higgs boson, making the search for rare Higgs decays a high priority,” says ATLAS physics coordinator Pamela Ferrari. "Through a meticulous combination of the individual results of ATLAS and CMS, we have made a step forward towards unravelling yet another riddle of the Higgs boson."

“The existence of new particles could have very significant effects on rare Higgs decay modes,” says CMS physics coordinator Florencia Canelli. “This study is a powerful test of the Standard Model. With the ongoing third run of the LHC and the future High-Luminosity LHC, we will be able to improve the precision of this test and probe ever rarer Higgs decays.”

angerard Fri, 05/26/2023 - 09:43 Publication Date Fri, 05/26/2023 - 11:00

Accelerator Report: Full house in the LHC LHC page 1 with the filling scheme indicated in the bottom left-hand corner of the display. This is a different filling scheme to the one mentioned in the article – over to you now to decipher the cryptic code! (Image: CERN)

On 11 May, four days before the original schedule had set a target of 1200 bunches per beam, the LHC made its final intensity ramp-up step to 2400 bunches per beam.

In fact, the intensity ramp-up step to 2400 bunches does not mean that there are exactly 2400 bunches in each beam, as the precise number depends on the filling scheme used. For the fill of 11 May, the actual number of bunches was 2347, which lasted close to 11 hours and contributed, with an intensity of 1.3x1011 protons per bunch, 0.48 fb-1 to the integrated luminosity goal of 75 fb-1 for 2023.

The filling scheme is defined according to the needs of the experiments, but it also depends on the beam production scheme selected in the injectors and the needs of the LHC machine itself – such as leaving sufficient empty space for the dump kickers to rise, or choosing specific bunch patterns to reduce the production of electron clouds. Therefore, it may be adapted during the run to maximise the production of luminosity within the given constraints of the LHC and the injectors.

One of the filling schemes defined for 2023 has 2374 bunches per ring. In the left-hand bottom of the LHC page 1 the filling scheme is indicated with what looks like a cryptic code and is described as:

25ns_2374b_2361_1730_1773_236bpi_13inj_hybrid_2INDIV

The first number, “25ns”, indicates the spacing between the bunches, while the second, “2374b”, is the total number of bunches per beam. The following three figures specify the number of bunches that will collide in each of the four LHC experiments: “2361” is the number of bunches out of the 2374 bunches that will collide in ATLAS (IP1) and CMS (IP5); “1730” is the number of bunches that will collide in ALICE (IP2); and “1773” is the number of bunches colliding in LHCb (IP8).

The remainder of the cryptic code is an indication of the beam production scheme used. “236bpi” indicates that the maximum bunch train length coming from the SPS and injected into the LHC contains 236 bunches, but shorter bunch trains may be injected too. “13inj” means that the LHC will inject 13 bunch trains per beam with a maximum length of 236 bunches each. The very last part of the cryptic code contains some special information: “hybrid” means that the bunch train of 236 bunches is produced in the injectors through the so-called hybrid scheme, which is a combination of different bunch patterns; “2INDIV” means that two individual or single bunches are also injected.

The hybrid scheme is produced in the injectors and provides the 236-bunch train with a pattern of seven batches, each with an “8b4e” bunch pattern of 8 bunches and 4 empty buckets (56 bunches). This is then followed by 5 batches of 36 bunches (180 bunches), resulting in the total length of the bunch train of 236 bunches. This hybrid scheme was chosen to maximise the luminosity production while keeping the heat load on the LHC beam screen, which is induced by the production of electron clouds, within acceptable limits. Leaving more gaps in the bunch train by introducing the four empty buckets will lower the total number of bunches that collide, but also limits the heat load, while leaving room to increase the number of protons per bunch from 1.3x1011 to the goal of 1.8x1011.

Today, the LHC is in full production with ~2400 bunches, and the next step is the gradual increase of the number of protons per bunch. As I write, the intensity per bunch has reached 1.6x1011 protons and the integrated luminosity in ATLAS and CMS is 10 fb-1 out of the 75 fb-1 targeted.

anschaef Thu, 05/25/2023 - 11:49 Byline Rende Steerenberg Publication Date Wed, 05/24/2023 - 11:46

Accelerator Report: Full house in the LHC LHC page 1 with the filling scheme indicated in the bottom left-hand corner of the display. This is a different filling scheme to the one mentioned in the article – over to you now to decipher the cryptic code! (Image: CERN)

On 11 May, four days before the original schedule had set a target of 1200 bunches per beam, the LHC made its final intensity ramp-up step to 2400 bunches per beam.

In fact, the intensity ramp-up step to 2400 bunches does not mean that there are exactly 2400 bunches in each beam, as the precise number depends on the filling scheme used. For the fill of 11 May, the actual number of bunches was 2347, which lasted close to 11 hours and contributed, with an intensity of 1.3x1011 protons per bunch, 0.48 fb-1 to the integrated luminosity goal of 75 fb-1 for 2023.

The filling scheme is defined according to the needs of the experiments, but it also depends on the beam production scheme selected in the injectors and the needs of the LHC machine itself – such as leaving sufficient empty space for the dump kickers to rise, or choosing specific bunch patterns to reduce the production of electron clouds. Therefore, it may be adapted during the run to maximise the production of luminosity within the given constraints of the LHC and the injectors.

One of the filling schemes defined for 2023 has 2374 bunches per ring. In the left-hand bottom of the LHC page 1 the filling scheme is indicated with what looks like a cryptic code and is described as:

25ns_2374b_2361_1730_1773_236bpi_13inj_hybrid_2INDIV

The first number, “25ns”, indicates the spacing between the bunches, while the second, “2374b”, is the total number of bunches per beam. The following three figures specify the number of bunches that will collide in each of the four LHC experiments: “2361” is the number of bunches out of the 2374 bunches that will collide in ATLAS (IP1) and CMS (IP5); “1730” is the number of bunches that will collide in ALICE (IP2); and “1773” is the number of bunches colliding in LHCb (IP8).

The remainder of the cryptic code is an indication of the beam production scheme used. “236bpi” indicates that the maximum bunch train length coming from the SPS and injected into the LHC contains 236 bunches, but shorter bunch trains may be injected too. “13inj” means that the LHC will inject 13 bunch trains per beam with a maximum length of 236 bunches each. The very last part of the cryptic code contains some special information: “hybrid” means that the bunch train of 236 bunches is produced in the injectors through the so-called hybrid scheme, which is a combination of different bunch patterns; “2INDIV” means that two individual or single bunches are also injected.

The hybrid scheme is produced in the injectors and provides the 236-bunch train with a pattern of seven batches, each with an “8b4e” bunch pattern of 8 bunches and 4 empty buckets (56 bunches). This is then followed by 5 batches of 36 bunches (180 bunches), resulting in the total length of the bunch train of 236 bunches. This hybrid scheme was chosen to maximise the luminosity production while keeping the heat load on the LHC beam screen, which is induced by the production of electron clouds, within acceptable limits. Leaving more gaps in the bunch train by introducing the four empty buckets will lower the total number of bunches that collide, but also limits the heat load, while leaving room to increase the number of protons per bunch from 1.3x1011 to the goal of 1.8x1011.

Today, the LHC is in full production with ~2400 bunches, and the next step is the gradual increase of the number of protons per bunch. As I write, the intensity per bunch has reached 1.6x1011 protons and the integrated luminosity in ATLAS and CMS is 10 fb-1 out of the 75 fb-1 targeted.

anschaef Thu, 05/25/2023 - 11:49 Byline Rende Steerenberg Publication Date Wed, 05/24/2023 - 11:46

Lebanon inaugurates the computer servers donated by CERN

On 23 May 2023, European and Lebanese stakeholders gathered in the Grand Sérail of Beirut – the headquarters of the Prime Minister of Lebanon – to inaugurate the computing equipment donated by CERN to the country’s academic institutes as part of the High-Performance Computing for Lebanon (HPC4L) project. The ceremony was the conclusion of a long journey whose many obstacles, on the backdrop of an economic crisis, have been overcome thanks to a staunch determination from all involved and an inspiring show of international solidarity.

The ceremony was attended by Swiss representatives and a CERN and CMS delegation. Enrica Porcari, Head of the CERN IT department, Patricia McBride, spokesperson of the CMS delegation and Martin Gastal, CERN advisor for the Middle East, each gave talks to an audience composed of Lebanese scientists and policymakers. Prime Minister H.E. Mr. Najib Mikati concluded the ceremony by saluting the remarkable efforts achieved by all involved in the HPC4L project.

The success of this project, initiated in 2016 by Martin Gastal, was made possible thanks to the unwavering commitment of the CMS collaboration, which, along with the Sharing Knowledge Foundation, launched a fundraising campaign to cover the cost of shipping the hardware, purchasing the equipment required to install it and training Lebanese technical staff at CERN. This knowledge transfer to the country's scientific community, which was organised by CMS, will ensure the smooth operation of the equipment in Lebanon.

The 144 computing servers and 24 disk servers donated by CERN as part of HPC4L have been installed in a dedicated computing centre run by a public–private consortium. This equipment will support the Lebanese academic community for all kinds of research activities, including high-energy physics. Crucially, 20% of the servers’ computing power will be dedicated to the Worldwide LHC Computing Grid (WLCG), a network of computing centres in 42 countries around the world used to store and analyse data from the LHC experiments – thereby bringing Lebanon closer to the LHC community.

________________________

Since 2012, CERN has regularly donated computing equipment that no longer meets its highly specific requirements on efficiency but is still more than adequate for less exacting environments. To date, a total of 2524 servers and 150 network switches have been donated by CERN to countries and international organisations, namely Algeria, Bulgaria, Ecuador, Egypt, Ghana, Mexico, Morocco, Lebanon, Nepal, Palestine, Pakistan, the Philippines, Senegal, Serbia, and the SESAME laboratory in Jordan. CERN strives to maximise its positive impact on society: these donations can play an important role in providing opportunities for researchers and students in their home countries, thus helping to avoid so-called ‘brain-drain’ scenarios.

thortala Thu, 05/25/2023 - 10:57 Byline Thomas Hortala Publication Date Thu, 05/25/2023 - 10:54

Lebanon inaugurates the computer servers donated by CERN

On 23 May 2023, European and Lebanese stakeholders gathered in the Grand Sérail of Beirut – the headquarters of the Prime Minister of Lebanon – to inaugurate the computing equipment donated by CERN to the country’s academic institutes as part of the High-Performance Computing for Lebanon (HPC4L) project. The ceremony was the conclusion of a long journey whose many obstacles, on the backdrop of an economic crisis, have been overcome thanks to a staunch determination from all involved and an inspiring show of international solidarity.

The ceremony was attended by Swiss representatives and a CERN and CMS delegation. Enrica Porcari, Head of the CERN IT department, Patricia McBride, spokesperson of the CMS delegation and Martin Gastal, CERN advisor for the Middle East, each gave talks to an audience composed of Lebanese scientists and policymakers. Prime Minister H.E. Mr. Najib Mikati concluded the ceremony by saluting the remarkable efforts achieved by all involved in the HPC4L project.

The success of this project, initiated in 2016 by Martin Gastal, was made possible thanks to the unwavering commitment of the CMS collaboration, which, along with the Sharing Knowledge Foundation, launched a fundraising campaign to cover the cost of shipping the hardware, purchasing the equipment required to install it and training Lebanese technical staff at CERN. This knowledge transfer to the country's scientific community, which was organised by CMS, will ensure the smooth operation of the equipment in Lebanon.

The 144 computing servers and 24 disk servers donated by CERN as part of HPC4L have been installed in a dedicated computing centre run by a public–private consortium. This equipment will support the Lebanese academic community for all kinds of research activities, including high-energy physics. Crucially, 20% of the servers’ computing power will be dedicated to the Worldwide LHC Computing Grid (WLCG), a network of computing centres in 42 countries around the world used to store and analyse data from the LHC experiments – thereby bringing Lebanon closer to the LHC community.

________________________

Since 2012, CERN has regularly donated computing equipment that no longer meets its highly specific requirements on efficiency but is still more than adequate for less exacting environments. To date, a total of 2524 servers and 150 network switches have been donated by CERN to countries and international organisations, namely Algeria, Bulgaria, Ecuador, Egypt, Ghana, Mexico, Morocco, Lebanon, Nepal, Palestine, Pakistan, the Philippines, Senegal, Serbia, and the SESAME laboratory in Jordan. CERN strives to maximise its positive impact on society: these donations can play an important role in providing opportunities for researchers and students in their home countries, thus helping to avoid so-called ‘brain-drain’ scenarios.

thortala Thu, 05/25/2023 - 10:57 Byline Thomas Hortala Publication Date Thu, 05/25/2023 - 10:54

Fireball at HiRadMat

Fireball (officially “HRMT-62”), a new experiment at the SPS HiRadMat facility, will receive its first beam this week. It is designed to study the micro-instabilities of a high-intensity electron-positron beam interacting with low-density plasma. The electron-positron beam is produced when a 440 GeV/c proton beam from the SPS impinges on a special target. The resulting beam propagates through the plasma and creates a highly unstable system: fluctuations of the magnetic field in the plasma cause charge separation in the beam, and this separation consequently causes further magnetic fluctuations in the plasma. This gives rise to non-linear phenomena and plasma emissions that have never been studied in this way before.

Members of the experimental team are working on the plasma cell during the 2022-2023 year-end-technical stop (YETS) in the HiRadMat surface laboratory. (Image: CERN)

This study should give new insights into extreme astrophysical phenomena, in particular blazar jets and gamma-ray bursts (GRBs). GRBs are among the most energetic phenomena in the Universe and, even though they have been observed in distant galaxies, the enormous amount of energy they release can disrupt radio communications on Earth – some theories even suggest that they affected the evolution of life on Earth. However, the fundamental physical processes involved in GRBs are still not understood.

“Without the unique HiRadMat facility, it would not have been possible to implement Fireball; it will be the first accelerator-driven experiment of this kind”, says Gianluca Gregori, the experiment’s spokesperson from the University of Oxford. “Fireball will help lift the veil on the microphysics processes that are not observable with satellites or ground-based telescopes and are impossible to simulate numerically.”

Installation of Fireball in HiRadMat’s irradiation area. (Image: CERN)

The experiment includes various instruments designed to study the formation of plasma instabilities and magnetic fields, in particular a custom-made magnetic spectrometer with a dipole magnet. “In order to power the magnetic spectrometer in a flexible and cost-effective way, along with SY/ABT and SY/EPC groups we disconnected one of the quadrupoles of the HiRadMat beamline and the optics were recalculated”, explains Nikos Charitonidis, HiRadMat facility coordinator. “The collaboration within CERN has once again been key to implementing all the necessary modifications in terms of beam and infrastructure. I’d really like to thank all the CERN groups involved for their collaborative effort in running this unique facility.”

Since its commissioning in 2011, HiRadMat has taken part in several European Transnational Access programmes, which have made the facility accessible to users from all over the world.

_____

For more information on the HiRadMat facility, read the article published for its 10th anniversary.

anschaef Wed, 05/24/2023 - 11:03 Publication Date Wed, 05/24/2023 - 11:01

Fireball at HiRadMat

Fireball (officially “HRMT-62”), a new experiment at the SPS HiRadMat facility, will receive its first beam this week. It is designed to study the micro-instabilities of a high-intensity electron-positron beam interacting with low-density plasma. The electron-positron beam is produced when a 440 GeV/c proton beam from the SPS impinges on a special target. The resulting beam propagates through the plasma and creates a highly unstable system: fluctuations of the magnetic field in the plasma cause charge separation in the beam, and this separation consequently causes further magnetic fluctuations in the plasma. This gives rise to non-linear phenomena and plasma emissions that have never been studied in this way before.

Members of the experimental team are working on the plasma cell during the 2022-2023 year-end-technical stop (YETS) in the HiRadMat surface laboratory. (Image: CERN)

This study should give new insights into extreme astrophysical phenomena, in particular blazar jets and gamma-ray bursts (GRBs). GRBs are among the most energetic phenomena in the Universe and, even though they have been observed in distant galaxies, the enormous amount of energy they release can disrupt radio communications on Earth – some theories even suggest that they affected the evolution of life on Earth. However, the fundamental physical processes involved in GRBs are still not understood.

“Without the unique HiRadMat facility, it would not have been possible to implement Fireball; it will be the first accelerator-driven experiment of this kind”, says Gianluca Gregori, the experiment’s spokesperson from the University of Oxford. “Fireball will help lift the veil on the microphysics processes that are not observable with satellites or ground-based telescopes and are impossible to simulate numerically.”

Installation of Fireball in HiRadMat’s irradiation area. (Image: CERN)

The experiment includes various instruments designed to study the formation of plasma instabilities and magnetic fields, in particular a custom-made magnetic spectrometer with a dipole magnet. “In order to power the magnetic spectrometer in a flexible and cost-effective way, along with SY/ABT and SY/EPC groups we disconnected one of the quadrupoles of the HiRadMat beamline and the optics were recalculated”, explains Nikos Charitonidis, HiRadMat facility coordinator. “The collaboration within CERN has once again been key to implementing all the necessary modifications in terms of beam and infrastructure. I’d really like to thank all the CERN groups involved for their collaborative effort in running this unique facility.”

Since its commissioning in 2011, HiRadMat has taken part in several European Transnational Access programmes, which have made the facility accessible to users from all over the world.

_____

For more information on the HiRadMat facility, read the article published for its 10th anniversary.

anschaef Wed, 05/24/2023 - 11:03 Publication Date Wed, 05/24/2023 - 11:01

Collaboration with CERN – an asset for scientific communities in the Middle East

Ever since its creation, CERN has sought to forge peaceful ties between countries all over the world, particularly through scientific collaboration, and the Middle East and North Africa (MENA) region is no exception. Today, the Organization is seeking to strengthen its links with countries in the region against the unique political backdrop. 

Partnerships between universities and the large LHC experiments (ATLAS, CMS, ALICE and LHCb) are central to CERN’s strategy in the MENA region. Although the level of involvement varies widely from one country to another, Martin Gastal, adviser for relations with the MENA region, notes strong interest across the region: “How a collaboration develops depends on many factors, in particular the country’s administrative and financial situation. Nevertheless, all the countries have demonstrated a desire to collaborate more closely with the CERN experiments.”

Morocco, which was the first country in the region to sign an international cooperation agreement with CERN, in April 1997, is a prime example: its partnership with ATLAS has since evolved into diplomatic relations with the Organization. These relations look set to continue to intensify as the country is considering joining CERN as an Associate Member State. The same is true for Egypt, which signed an international cooperation agreement in 2006, as the Egyptian Minister of Higher Education has also expressed a desire for Egypt to become an Associate Member State of CERN. In addition, CERN is on the receiving end of fruitful initiatives by various other countries, such as Bahrain, which, in summer 2022, offered its services to build a piece of equipment for the CMS detector – an aluminium access frame for the tracker region and the associated installation jig.

Leaving aside the machines, these agreements have an impact on countless individual careers, giving dozens of students the opportunity to cut their teeth at CERN. Every year, summer students from the region are invited to visit the LHC experiments, where they are shown round by colleagues from their region and get to see the contributions made by MENA universities to particle physics research.

In parallel, efforts to prevent a brain drain from the MENA region are a lynchpin of CERN’s involvement there. By building up the capacity of local institutes, CERN helps make the countries in the region attractive hubs for particle physics research and for science and technology in general. An obvious example of this is the donation of IT equipment, such as the servers donated in 2019 to An-Najah National University in the West Bank, which paved the way for the university to join the ATLAS collaboration in March 2022, opening up career opportunities for dozens of Palestinian students and researchers. Similarly, CERN sent a large quantity of computer servers to Lebanon following a fundraising campaign for the High-Performance Computing for Lebanon (HPC4L) project, which aims to support the Lebanese scientific community. These donations support students and researchers in their work in the fields of artificial intelligence, algorithm development and machine learning for experimental physics.

In 2017, CERN was granted the status of Observer to the Council of SESAME, the International Centre for Synchrotron Light for Experimental Science and Applications in the Middle East. This organisation, based in Jordan, is the latest to have applied the CERN governance model to particle physics. Transcending political barriers, the laboratory has for the first time given representatives from countries across the region, including Iran and Israel, the opportunity to reach shared positions on scientific cooperation. “The common denominator is science, which makes the bridge of peace easier to cross – they are able to speak freely,” says Martin Gastal.

CERN’s involvement in SESAME is just one of several avenues being explored by the Organization to promote science in the MENA region. Its intention is to tap into the enthusiasm of the region’s countries and scientific communities to chart a path forward with them.

Reema Altamimi is from Nablus in Palestine. She is currently studying for a Masters degree at the University of Paris II, and spent a period as an intern in the Education, Communication and Outreach group at CERN in 2022, thanks to a grant from the Sharing Knowledge Foundation.

thortala Wed, 05/24/2023 - 10:36 Byline Reema Altamimi Publication Date Wed, 05/24/2023 - 10:34

Collaboration with CERN – an asset for scientific communities in the Middle East

Ever since its creation, CERN has sought to forge peaceful ties between countries all over the world, particularly through scientific collaboration, and the Middle East and North Africa (MENA) region is no exception. Today, the Organization is seeking to strengthen its links with countries in the region against the unique political backdrop. 

Partnerships between universities and the large LHC experiments (ATLAS, CMS, ALICE and LHCb) are central to CERN’s strategy in the MENA region. Although the level of involvement varies widely from one country to another, Martin Gastal, adviser for relations with the MENA region, notes strong interest across the region: “How a collaboration develops depends on many factors, in particular the country’s administrative and financial situation. Nevertheless, all the countries have demonstrated a desire to collaborate more closely with the CERN experiments.”

Morocco, which was the first country in the region to sign an international cooperation agreement with CERN, in April 1997, is a prime example: its partnership with ATLAS has since evolved into diplomatic relations with the Organization. These relations look set to continue to intensify as the country is considering joining CERN as an Associate Member State. The same is true for Egypt, which signed an international cooperation agreement in 2006, as the Egyptian Minister of Higher Education has also expressed a desire for Egypt to become an Associate Member State of CERN. In addition, CERN is on the receiving end of fruitful initiatives by various other countries, such as Bahrain, which, in summer 2022, offered its services to build a piece of equipment for the CMS detector – an aluminium access frame for the tracker region and the associated installation jig.

Leaving aside the machines, these agreements have an impact on countless individual careers, giving dozens of students the opportunity to cut their teeth at CERN. Every year, summer students from the region are invited to visit the LHC experiments, where they are shown round by colleagues from their region and get to see the contributions made by MENA universities to particle physics research.

In parallel, efforts to prevent a brain drain from the MENA region are a lynchpin of CERN’s involvement there. By building up the capacity of local institutes, CERN helps make the countries in the region attractive hubs for particle physics research and for science and technology in general. An obvious example of this is the donation of IT equipment, such as the servers donated in 2019 to An-Najah National University in the West Bank, which paved the way for the university to join the ATLAS collaboration in March 2022, opening up career opportunities for dozens of Palestinian students and researchers. Similarly, CERN sent a large quantity of computer servers to Lebanon following a fundraising campaign for the High-Performance Computing for Lebanon (HPC4L) project, which aims to support the Lebanese scientific community. These donations support students and researchers in their work in the fields of artificial intelligence, algorithm development and machine learning for experimental physics.

In 2017, CERN was granted the status of Observer to the Council of SESAME, the International Centre for Synchrotron Light for Experimental Science and Applications in the Middle East. This organisation, based in Jordan, is the latest to have applied the CERN governance model to particle physics. Transcending political barriers, the laboratory has for the first time given representatives from countries across the region, including Iran and Israel, the opportunity to reach shared positions on scientific cooperation. “The common denominator is science, which makes the bridge of peace easier to cross – they are able to speak freely,” says Martin Gastal.

CERN’s involvement in SESAME is just one of several avenues being explored by the Organization to promote science in the MENA region. Its intention is to tap into the enthusiasm of the region’s countries and scientific communities to chart a path forward with them.

Reema Altamimi is from Nablus in Palestine. She is currently studying for a Masters degree at the University of Paris II, and spent a period as an intern in the Education, Communication and Outreach group at CERN in 2022, thanks to a grant from the Sharing Knowledge Foundation.

thortala Wed, 05/24/2023 - 10:36 Byline Reema Altamimi Publication Date Wed, 05/24/2023 - 10:34

ISOLDE takes a solid tick forward towards a nuclear clock

Atomic clocks are the world’s most precise timekeepers. Based on periodic transitions between two electronic states of an atom, they can track the passage of time with a precision as high as one part in a quintillion, meaning that they won’t lose or gain a second over 30 billion years – more than twice the age of the Universe.

In a paper published today in Nature, an international team at CERN’s nuclear physics facility, ISOLDE, reports a key step towards building a clock that would be based on a periodic transition between two states of an atomic nucleus – the nucleus of an isotope of the element thorium, thorium-229.

Such a nuclear clock could be more precise than today’s most precise atomic clocks, thanks to the different size and constituents of a nucleus compared to those of an atom. In addition, it could serve as a sensitive tool with which to search for new phenomena beyond the Standard Model, currently the best description there is of the subatomic world. For instance, it could allow researchers to look for variations over time of fundamental constants of nature and to search for ultralight dark matter.

Artist’s impression of a nuclear clock. (Image: APS/Ann. Phys.  531, 1800381 (2019))

Ever since 2003, when Ekkehard Peik and Christian Tamm proposed a nuclear clock based on the transition between the ground state of the thorium-229 nucleus and the first, higher-energy state (called an isomer), researchers have been racing to observe and characterise this nuclear transition.

In the two decades, researchers have measured with ever increasing precision the isomer’s energy, the precise value of which is required to develop lasers to drive the transition to the isomer. However, despite much effort, they have not succeeded in observing the light emitted in the transition from the isomer to the ground state. This phenomenon, known in nuclear physicists’ parlance as the radiative decay of the isomer, which has a relatively long lifetime, is a key ingredient in developing a nuclear clock, because it would allow, among other things, the isomer’s energy to be determined with higher precision.

A team working at ISOLDE has now achieved this feat by producing thorium-229 nuclei in the isomeric state in a novel way and investigating the nuclei using a technique called vacuum-ultraviolet spectroscopy. The wavelength of the observed light corresponds to an isomer’s energy of 8.338 electronvolts (eV) with an uncertainty of 0.024 eV – a value that is seven times more precise than the previous most precise measurements.

Significant to the team’s success was the production of isomeric thorium-229 nuclei via the so-called beta decay of actinium-229 isotopes, which were made at ISOLDE and incorporated in calcium fluoride or magnesium fluoride crystals.

“ISOLDE is currently one of only two facilities in the world that can produce actinium-229 isotopes,” says the main author of the paper, Sandro Kraemer. “By incorporating these isotopes in calcium fluoride or magnesium fluoride crystals, we produced many more isomeric thorium-229 nuclei and increased our chances of observing their radiative decay.”

The novel approach of producing thorium-229 nuclei also made it possible to determine the lifetime of the isomer in the magnesium fluoride crystal. Knowledge of this lifetime is needed to predict the precision of a thorium-229 nuclear clock based on this solid-state system. The long lifetime that was measured, namely 16.1 minutes with an uncertainty of 2.5 minutes, confirms theoretical estimates and indicates that a clock precision competitive with that of today’s most precise atomic clocks is attainable.

“Solid-state systems such as magnesium fluoride crystals are one of two possible settings in which to build a future thorium-229 nuclear clock” says the team’s spokesperson, Piet Van Duppen. “Our study marks a crucial step in this direction, and it will facilitate the development of the lasers needed to drive the periodic transition that would make such a clock tick.”

 

ISOLDE takes a solid tick forward towards a nuclear clock. (Video: CERN)

 

ssanchis Tue, 05/23/2023 - 14:37 Publication Date Wed, 05/24/2023 - 17:05

ISOLDE takes a solid tick forward towards a nuclear clock

Atomic clocks are the world’s most precise timekeepers. Based on periodic transitions between two electronic states of an atom, they can track the passage of time with a precision as high as one part in a quintillion, meaning that they won’t lose or gain a second over 30 billion years – more than twice the age of the Universe.

In a paper published today in Nature, an international team at CERN’s nuclear physics facility, ISOLDE, reports a key step towards building a clock that would be based on a periodic transition between two states of an atomic nucleus – the nucleus of an isotope of the element thorium, thorium-229.

Such a nuclear clock could be more precise than today’s most precise atomic clocks, thanks to the different size and constituents of a nucleus compared to those of an atom. In addition, it could serve as a sensitive tool with which to search for new phenomena beyond the Standard Model, currently the best description there is of the subatomic world. For instance, it could allow researchers to look for variations over time of fundamental constants of nature and to search for ultralight dark matter.

Artist’s impression of a nuclear clock. (Image: APS/Ann. Phys.  531, 1800381 (2019))

Ever since 2003, when Ekkehard Peik and Christian Tamm proposed a nuclear clock based on the transition between the ground state of the thorium-229 nucleus and the first, higher-energy state (called an isomer), researchers have been racing to observe and characterise this nuclear transition.

In the two decades, researchers have measured with ever increasing precision the isomer’s energy, the precise value of which is required to develop lasers to drive the transition to the isomer. However, despite much effort, they have not succeeded in observing the light emitted in the transition from the isomer to the ground state. This phenomenon, known in nuclear physicists’ parlance as the radiative decay of the isomer, which has a relatively long lifetime, is a key ingredient in developing a nuclear clock, because it would allow, among other things, the isomer’s energy to be determined with higher precision.

A team working at ISOLDE has now achieved this feat by producing thorium-229 nuclei in the isomeric state in a novel way and investigating the nuclei using a technique called vacuum-ultraviolet spectroscopy. The wavelength of the observed light corresponds to an isomer’s energy of 8.338 electronvolts (eV) with an uncertainty of 0.024 eV – a value that is seven times more precise than the previous most precise measurements.

Significant to the team’s success was the production of isomeric thorium-229 nuclei via the so-called beta decay of actinium-229 isotopes, which were made at ISOLDE and incorporated in calcium fluoride or magnesium fluoride crystals.

“ISOLDE is currently one of only two facilities in the world that can produce actinium-229 isotopes,” says the main author of the paper, Sandro Kraemer. “By incorporating these isotopes in calcium fluoride or magnesium fluoride crystals, we produced many more isomeric thorium-229 nuclei and increased our chances of observing their radiative decay.”

The novel approach of producing thorium-229 nuclei also made it possible to determine the lifetime of the isomer in the magnesium fluoride crystal. Knowledge of this lifetime is needed to predict the precision of a thorium-229 nuclear clock based on this solid-state system. The long lifetime that was measured, namely 16.1 minutes with an uncertainty of 2.5 minutes, confirms theoretical estimates and indicates that a clock precision competitive with that of today’s most precise atomic clocks is attainable.

“Solid-state systems such as magnesium fluoride crystals are one of two possible settings in which to build a future thorium-229 nuclear clock” says the team’s spokesperson, Piet Van Duppen. “Our study marks a crucial step in this direction, and it will facilitate the development of the lasers needed to drive the periodic transition that would make such a clock tick.”

 

ISOLDE takes a solid tick forward towards a nuclear clock. (Video: CERN)

 

ssanchis Tue, 05/23/2023 - 14:37 Publication Date Wed, 05/24/2023 - 17:05

Computer security: A bank à la CERN

When doing cybersecurity, protective measures must be adapted to your environment and needs. For a bank, it’s obvious that protecting physical and digital money, and confidential data about customers, is of the utmost importance. Hence, security is tight, well controlled and comes with lots of restrictions, giving attackers a very small attack surface to penetrate through. For CERN, with its open environment and academic freedom, the “bank” approach definitely doesn’t work. But what if we were to build a bank à la CERN?

First, our bank would have many entrances: through CERN’s outer perimeter firewall or via GSM, but also allowing people to connect to the Wi-Fi network once they’re registered. Instead of having single entrances, like one Windows Terminal server cluster or one LXPLUS cluster, our bank has both. Plus the possibility to tunnel through using Windows Gateways or “SSHUTTLE”. Similarly complex and diverse is the situation for entering the Technical Network used for accelerator controls and technical infrastructure: Terminal servers, Linux gateways, access for selected and approved virtual machines, web proxies allowing tunnelling, etc. On the way out, a bank would have locked you out. No news pages. No Facebook or Instagram. No Amazon. Internet access is tied down, strictly controlled, and reserved for professional purposes only. Tolerance of “personal use” just doesn’t exist.

Secondly, our bank would be crowded with strangers: “bring your own device” (BYOD) is a common standard at CERN. A bank would strictly keep out any devices that are not centrally managed. There, you wouldn’t have your personal laptop or smartphone on par with its internal network; you wouldn’t have admin rights on any of your professional devices; the operating system and applications would be imposed on you; and any personal use would be blocked.  

Thirdly, our bank wouldn’t know who you really are ─ in the digital sense. At the CERN bank, you log in with your account and a password, but that’s it. There’s no strong verification to check whether the person who’s logging in and knows the password is really who they claim to be. A real bank would have put in place two-factor authentication for each and every access, as well as tight access controls and a tight lock-out procedure in case you’re logging in from an “unusual location”. No exceptions even if you left your second factor, your smartphone, at home. You’d have to run home and get it.

Fourth, our bank would have flying ads and posters from other companies all over the walls. As we don’t distinguish between personal and professional usage, our bank’s email addresses can be used for other things. Signing up on for a social media account? Sure! Registering with your local grocery store? Done deal. Buying theatre tickets? There you go. Plus, messages can be automatically forwarded to any third-party mail provider if you believe their mail service is better. All of that’s a no-go in a real bank. Its email address is for professional business only. And all emails remain on their mail servers to guarantee confidentiality. Reading emails on your personal device is blocked.

Fifth, our bank’s systems accept any currency transaction. Importing the newest Python library from Anaconda? Downloading a fancy container image from Docker? Running NPM to update local code? All easily possible and all eventually pushed into production. Without checks, curation or control. A real bank applies maximum due diligence and a tight authoring process. While that slows down any deployment, it reduces the risk that “counterfeit money” makes it into their vaults.

So, would you trust our bank with your money? Better not. Fortunately, we’re not a bank. And our balance between academic freedom, accelerator and experiment operations, and “security” is definitely not the same as that between “finance” and “security”. In fact, a bank-like balance, a bank-like security posture, would kill our academic freedom and inhibit our efficient and effective operations. Still, don’t you think we could do better? We could:

1. Ensure that our entrances, our gates, are consolidated and better controlled. While our internet gate is well guarded , initial discussions on reviewing the interaction and inter-dependency between IT services, developers and the Technical Network have just started and need your commitment;
2. Improve the protection of our pool of BYOD, as BYOD is the only way for the Organization to accommodate thousands of researchers coming and going, connecting locally and remotely every month. Therefore, additional protective means have been made available for BYOD and for devices owned by CERN;
3. Make (wider) use of two-factor authentication to protect our computing accounts and their passwords from any malicious use;
4. Definitely be more vigilant and careful with CERN email addresses and when browsing the web. Just “STOP ─ THINK ─ DON’T CLICK” before risking too much; and
5. Put in place a better software development process, in particular when importing packages, libraries, virtual images and containers from third-party sources.

Do you want to learn more about computer security incidents and issues at CERN? Follow our Monthly Report. For further information, questions or help, check our website or contact us at Computer.Security@cern.ch.

thortala Tue, 05/23/2023 - 10:39 Byline Computer Security team Publication Date Tue, 05/23/2023 - 10:18

Computer security: A bank à la CERN

When doing cybersecurity, protective measures must be adapted to your environment and needs. For a bank, it’s obvious that protecting physical and digital money, and confidential data about customers, is of the utmost importance. Hence, security is tight, well controlled and comes with lots of restrictions, giving attackers a very small attack surface to penetrate through. For CERN, with its open environment and academic freedom, the “bank” approach definitely doesn’t work. But what if we were to build a bank à la CERN?

First, our bank would have many entrances: through CERN’s outer perimeter firewall or via GSM, but also allowing people to connect to the Wi-Fi network once they’re registered. Instead of having single entrances, like one Windows Terminal server cluster or one LXPLUS cluster, our bank has both. Plus the possibility to tunnel through using Windows Gateways or “SSHUTTLE”. Similarly complex and diverse is the situation for entering the Technical Network used for accelerator controls and technical infrastructure: Terminal servers, Linux gateways, access for selected and approved virtual machines, web proxies allowing tunnelling, etc. On the way out, a bank would have locked you out. No news pages. No Facebook or Instagram. No Amazon. Internet access is tied down, strictly controlled, and reserved for professional purposes only. Tolerance of “personal use” just doesn’t exist.

Secondly, our bank would be crowded with strangers: “bring your own device” (BYOD) is a common standard at CERN. A bank would strictly keep out any devices that are not centrally managed. There, you wouldn’t have your personal laptop or smartphone on par with its internal network; you wouldn’t have admin rights on any of your professional devices; the operating system and applications would be imposed on you; and any personal use would be blocked.  

Thirdly, our bank wouldn’t know who you really are ─ in the digital sense. At the CERN bank, you log in with your account and a password, but that’s it. There’s no strong verification to check whether the person who’s logging in and knows the password is really who they claim to be. A real bank would have put in place two-factor authentication for each and every access, as well as tight access controls and a tight lock-out procedure in case you’re logging in from an “unusual location”. No exceptions even if you left your second factor, your smartphone, at home. You’d have to run home and get it.

Fourth, our bank would have flying ads and posters from other companies all over the walls. As we don’t distinguish between personal and professional usage, our bank’s email addresses can be used for other things. Signing up on for a social media account? Sure! Registering with your local grocery store? Done deal. Buying theatre tickets? There you go. Plus, messages can be automatically forwarded to any third-party mail provider if you believe their mail service is better. All of that’s a no-go in a real bank. Its email address is for professional business only. And all emails remain on their mail servers to guarantee confidentiality. Reading emails on your personal device is blocked.

Fifth, our bank’s systems accept any currency transaction. Importing the newest Python library from Anaconda? Downloading a fancy container image from Docker? Running NPM to update local code? All easily possible and all eventually pushed into production. Without checks, curation or control. A real bank applies maximum due diligence and a tight authoring process. While that slows down any deployment, it reduces the risk that “counterfeit money” makes it into their vaults.

So, would you trust our bank with your money? Better not. Fortunately, we’re not a bank. And our balance between academic freedom, accelerator and experiment operations, and “security” is definitely not the same as that between “finance” and “security”. In fact, a bank-like balance, a bank-like security posture, would kill our academic freedom and inhibit our efficient and effective operations. Still, don’t you think we could do better? We could:

1. Ensure that our entrances, our gates, are consolidated and better controlled. While our internet gate is well guarded , initial discussions on reviewing the interaction and inter-dependency between IT services, developers and the Technical Network have just started and need your commitment;
2. Improve the protection of our pool of BYOD, as BYOD is the only way for the Organization to accommodate thousands of researchers coming and going, connecting locally and remotely every month. Therefore, additional protective means have been made available for BYOD and for devices owned by CERN;
3. Make (wider) use of two-factor authentication to protect our computing accounts and their passwords from any malicious use;
4. Definitely be more vigilant and careful with CERN email addresses and when browsing the web. Just “STOP ─ THINK ─ DON’T CLICK” before risking too much; and
5. Put in place a better software development process, in particular when importing packages, libraries, virtual images and containers from third-party sources.

Do you want to learn more about computer security incidents and issues at CERN? Follow our Monthly Report. For further information, questions or help, check our website or contact us at Computer.Security@cern.ch.

thortala Tue, 05/23/2023 - 10:39 Byline Computer Security team Publication Date Tue, 05/23/2023 - 10:18

Eleven successful years and counting for the Be a Scientist project

For four months, 30 teachers and 684 schoolchildren aged from 7 to 12 from the Geneva, Ain and Haute-Savoie regions were initiated into the scientific research process. Like scientists looking for particles that are invisible to the human eye, the pupils came up with hypotheses, collected data and conducted experiments to try to work out what was inside mystery boxes provided by CERN. All they had been told was that they mustn’t open or damage the boxes in the process.

As the project unfolded, the 30 classes taking part used a collaborative web platform to share how their investigations were progressing. They also had the chance to visit CERN and the University of Geneva’s PhysiScope. Their thinking and research was enhanced by being immersed in the laboratory environment and talking to scientists.

The project rounded off in style with a final conference in CERN’s Globe of Science and Innovation on Thursday, 11 May 2023. Pupils from three classes in Geneva shared their findings in the form of an animated film, posters and exhibition stands. After months of suspense, the pupils also finally found out what was inside the boxes.

The Be a Scientist project, which was launched in 2011, is an education programme based on a collaboration between the University of Geneva (the Physiscope and the Laboratory of Didactics and Science Epistemology), the Geneva Department of Education and the French Ministry of Education.

Are you a teacher and want to take part in a future programme? Visit https://voisins.cern/en/be-scientist. Registration for the 2024 edition will open at the end of the summer.

thortala Tue, 05/23/2023 - 09:50 Publication Date Tue, 05/23/2023 - 09:49

Eleven successful years and counting for the Be a Scientist project

For four months, 30 teachers and 684 schoolchildren aged from 7 to 12 from the Geneva, Ain and Haute-Savoie regions were initiated into the scientific research process. Like scientists looking for particles that are invisible to the human eye, the pupils came up with hypotheses, collected data and conducted experiments to try to work out what was inside mystery boxes provided by CERN. All they had been told was that they mustn’t open or damage the boxes in the process.

As the project unfolded, the 30 classes taking part used a collaborative web platform to share how their investigations were progressing. They also had the chance to visit CERN and the University of Geneva’s PhysiScope. Their thinking and research was enhanced by being immersed in the laboratory environment and talking to scientists.

The project rounded off in style with a final conference in CERN’s Globe of Science and Innovation on Thursday, 11 May 2023. Pupils from three classes in Geneva shared their findings in the form of an animated film, posters and exhibition stands. After months of suspense, the pupils also finally found out what was inside the boxes.

The Be a Scientist project, which was launched in 2011, is an education programme based on a collaboration between the University of Geneva (the Physiscope and the Laboratory of Didactics and Science Epistemology), the Geneva Department of Education and the French Ministry of Education.

Are you a teacher and want to take part in a future programme? Visit https://voisins.cern/en/be-scientist. Registration for the 2024 edition will open at the end of the summer.

thortala Tue, 05/23/2023 - 09:50 Publication Date Tue, 05/23/2023 - 09:49

Let’s quantum

On 6 May, CERN hosted its first-ever workshop for high-school students on all things quantum. The event was organised jointly by CERN’s Quantum Technology Initiative (QTI) and Finland’s QPlayLearn team in the context of World Quantum Day 2023.

A total of 30 enthusiastic students from local schools in France and Switzerland attended the workshop. During the half-day event, the students, aged 15 to 18, were introduced to the fascinating field of quantum science and technology.

The workshop kicked off with a lecture held in French by Su Yeon Chang, a doctoral student in quantum computing at CERN. In her lecture, Chang explained what quantum physics is and how its fundamental concepts work. She also covered the basic principles of quantum computing and its potential and current challenges.

An interactive “Learn-by-Play” session followed this introductory lecture and was set up as a tournament. Split into small groups of three, the students rotated through seven quantum-game stations, gathering points based on the number and the complexity of the levels they completed in the games. Each game corresponded to one quantum physics concept, such as quantum states, quantum superposition, quantum entanglement and quantum tunnelling. While following the instructions provided and playing the games, the students built up intuition about the various principles of quantum physics. Supervised by mentors at each station, they were able to ask questions and expand their understanding of a particular concept before going on to the next game.

“We learned a lot in just half a day, starting with a lecture and continuing with fun and interesting games,” says William Schwager, a student from the Collège Sismondi in Geneva. “I would certainly recommend this event to anyone who is interested in science.”

At the end of the workshop, three winning teams were announced and were awarded first-, second- and third-place certificates. Quantum-themed giveaway items were also handed out to every participant to encourage further exploration of the various aspects of quantum science and technology.

“Promoting early quantum-physics education is essential to ensure that we can form a generation of researchers and engineers that is able to develop and use quantum technologies in the future”, says Alberto Di Meglio, coordinator of the CERN QTI. “By allowing students to explore topics that are new or supplementary to their curriculum, in a way that is both accessible and interesting to them, we help build the quantum experts and quantum ecosystems of tomorrow.”

The event was a great success, and it would not have been possible without the support of QPlayLearn, which provided content for the Learn-by-Play session. QPlayLearn is a team of quantum physicists, educational and social scientists and professional communicators working to teach the beauty of quantum physics and the impact of quantum technologies in an engaging and clear, yet accurate, way to everyone.

“We believe in the importance of science education and scientific literacy for our society. We also believe that the learning process can be fun as well as effective, and should always take into account multiple needs and backgrounds,” says Caterina Foti, coordinator of QPlayLearn. “Development of innovative interactive tools for multilevel education for all possible audiences lies at the core of our mission.”

abelchio Mon, 05/15/2023 - 14:14 Byline Anastasiia Lazuka Publication Date Tue, 05/16/2023 - 10:00

Let’s quantum

On 6 May, CERN hosted its first-ever workshop for high-school students on all things quantum. The event was organised jointly by CERN’s Quantum Technology Initiative (QTI) and Finland’s QPlayLearn team in the context of World Quantum Day 2023.

A total of 30 enthusiastic students from local schools in France and Switzerland attended the workshop. During the half-day event, the students, aged 15 to 18, were introduced to the fascinating field of quantum science and technology.

The workshop kicked off with a lecture held in French by Su Yeon Chang, a doctoral student in quantum computing at CERN. In her lecture, Chang explained what quantum physics is and how its fundamental concepts work. She also covered the basic principles of quantum computing and its potential and current challenges.

An interactive “Learn-by-Play” session followed this introductory lecture and was set up as a tournament. Split into small groups of three, the students rotated through seven quantum-game stations, gathering points based on the number and the complexity of the levels they completed in the games. Each game corresponded to one quantum physics concept, such as quantum states, quantum superposition, quantum entanglement and quantum tunnelling. While following the instructions provided and playing the games, the students built up intuition about the various principles of quantum physics. Supervised by mentors at each station, they were able to ask questions and expand their understanding of a particular concept before going on to the next game.

“We learned a lot in just half a day, starting with a lecture and continuing with fun and interesting games,” says William Schwager, a student from the Collège Sismondi in Geneva. “I would certainly recommend this event to anyone who is interested in science.”

At the end of the workshop, three winning teams were announced and were awarded first-, second- and third-place certificates. Quantum-themed giveaway items were also handed out to every participant to encourage further exploration of the various aspects of quantum science and technology.

“Promoting early quantum-physics education is essential to ensure that we can form a generation of researchers and engineers that is able to develop and use quantum technologies in the future”, says Alberto Di Meglio, coordinator of the CERN QTI. “By allowing students to explore topics that are new or supplementary to their curriculum, in a way that is both accessible and interesting to them, we help build the quantum experts and quantum ecosystems of tomorrow.”

The event was a great success, and it would not have been possible without the support of QPlayLearn, which provided content for the Learn-by-Play session. QPlayLearn is a team of quantum physicists, educational and social scientists and professional communicators working to teach the beauty of quantum physics and the impact of quantum technologies in an engaging and clear, yet accurate, way to everyone.

“We believe in the importance of science education and scientific literacy for our society. We also believe that the learning process can be fun as well as effective, and should always take into account multiple needs and backgrounds,” says Caterina Foti, coordinator of QPlayLearn. “Development of innovative interactive tools for multilevel education for all possible audiences lies at the core of our mission.”

abelchio Mon, 05/15/2023 - 14:14 Byline Anastasiia Lazuka Publication Date Tue, 05/16/2023 - 10:00

Accelerator Report: mostly on schedule, sometimes not…

Today, almost the whole accelerator complex is operational and providing beams to all the experimental facilities as scheduled. The LHC experiments are taking data, while the LHC is nearing the end of the intensity ramp-up phase; already last weekend it was colliding beams with 1200 bunches per beam, one week earlier than initially scheduled. As I write, beams with ~1800 bunches are in collision – the last step before the full machine is filled with ~2400 bunches per beam.

This picture shows the AD quadrupole where the water leak was situated. This is a half quadrupole that simultaneously generates a dipolar field to deviate the antiproton beam and a quadrupolar field to focus the antiprotons. (Image: CERN)

The only physics that has not yet started is at the Antiproton Decelerator (AD), which was initially scheduled to start on 11 May, but unfortunately had to be delayed due to a technical problem. On 14 March, during the hardware recommissioning of the antiproton complex concluding the year-end technical stop (YETS), a water leak appeared in a special quadrupole magnet in the AD machine. The leak, situated at the entry of the insulated magnet coils, could not be repaired in situ, which meant that the roof of the AD tunnel had to be opened and the magnet removed for repair in the magnet workshop. The coils were exchanged, the magnet was tested and the magnet field maps were measured. After full validation, the repaired magnet was re-installed in the AD tunnel on 28 April, which was followed by electrical and vacuum reconnection. After the initial vacuum pump down, vacuum leak detections were performed with success. Since the vacuum in the AD machine needs to be of very high quality, the vacuum chamber and associated equipment had to be baked-out. This is a more than two-week-long process that started last week: the vacuum chamber and associated equipment for the whole vacuum sector concerned are heated up to evacuate and pump the residual gas molecules, including those from the surface layer of the vacuum chamber. Upon completion of the bake-out, cooldown is needed, equipment needs to be removed and the machine made ready to be commissioning with beam.

While various teams were busy repairing and validating the magnet and its reconnection, the AD-ELENA operations team continued the hardware recommissioning of the other parts of the AD, while also performing ELENA beam commissioning with H- ions from a local ion source with the aim of minimising the time lost and being as efficient as possible for the recommissioning of the antiproton beams for the experiments.

This means that the beam commissioning of the AD will start on 12 June and be compressed to aim for delivery of antiprotons from ELENA to the eagerly waiting AD-ELENA experiments on 30 June.

All the technical teams at CERN work hard during the YETS to execute the huge task of corrective and preventive maintenance in addition to consolidation and upgrade activities. Thanks to their efforts and high-quality work, most of the accelerator complex was recommissioned efficiently and delivered nearly all the required beams on – and in some cases ahead of – schedule. Sometimes, nevertheless, a single component that had previously functioned well and showed no signs of weakness can cause problems that force us to change some of our plans.

anschaef Fri, 05/12/2023 - 09:33 Byline Rende Steerenberg Publication Date Fri, 05/12/2023 - 09:31

Accelerator Report: mostly on schedule, sometimes not…

Today, almost the whole accelerator complex is operational and providing beams to all the experimental facilities as scheduled. The LHC experiments are taking data, while the LHC is nearing the end of the intensity ramp-up phase; already last weekend it was colliding beams with 1200 bunches per beam, one week earlier than initially scheduled. As I write, beams with ~1800 bunches are in collision – the last step before the full machine is filled with ~2400 bunches per beam.

This picture shows the AD quadrupole where the water leak was situated. This is a half quadrupole that simultaneously generates a dipolar field to deviate the antiproton beam and a quadrupolar field to focus the antiprotons. (Image: CERN)

The only physics that has not yet started is at the Antiproton Decelerator (AD), which was initially scheduled to start on 11 May, but unfortunately had to be delayed due to a technical problem. On 14 March, during the hardware recommissioning of the antiproton complex concluding the year-end technical stop (YETS), a water leak appeared in a special quadrupole magnet in the AD machine. The leak, situated at the entry of the insulated magnet coils, could not be repaired in situ, which meant that the roof of the AD tunnel had to be opened and the magnet removed for repair in the magnet workshop. The coils were exchanged, the magnet was tested and the magnet field maps were measured. After full validation, the repaired magnet was re-installed in the AD tunnel on 28 April, which was followed by electrical and vacuum reconnection. After the initial vacuum pump down, vacuum leak detections were performed with success. Since the vacuum in the AD machine needs to be of very high quality, the vacuum chamber and associated equipment had to be baked-out. This is a more than two-week-long process that started last week: the vacuum chamber and associated equipment for the whole vacuum sector concerned are heated up to evacuate and pump the residual gas molecules, including those from the surface layer of the vacuum chamber. Upon completion of the bake-out, cooldown is needed, equipment needs to be removed and the machine made ready to be commissioning with beam.

While various teams were busy repairing and validating the magnet and its reconnection, the AD-ELENA operations team continued the hardware recommissioning of the other parts of the AD, while also performing ELENA beam commissioning with H- ions from a local ion source with the aim of minimising the time lost and being as efficient as possible for the recommissioning of the antiproton beams for the experiments.

This means that the beam commissioning of the AD will start on 12 June and be compressed to aim for delivery of antiprotons from ELENA to the eagerly waiting AD-ELENA experiments on 30 June.

All the technical teams at CERN work hard during the YETS to execute the huge task of corrective and preventive maintenance in addition to consolidation and upgrade activities. Thanks to their efforts and high-quality work, most of the accelerator complex was recommissioned efficiently and delivered nearly all the required beams on – and in some cases ahead of – schedule. Sometimes, nevertheless, a single component that had previously functioned well and showed no signs of weakness can cause problems that force us to change some of our plans.

anschaef Fri, 05/12/2023 - 09:33 Byline Rende Steerenberg Publication Date Fri, 05/12/2023 - 09:31