Cern News
Accelerator Report: LHC pausing production for maintenance to stay strong and highly performing
Even the most cutting-edge machines require moments of respite. That’s why, in the early morning of Monday, 19 June, LHC operation was paused for one week to allow the technical teams to carry out preventive and corrective maintenance on the machine and its subsystems.
One week earlier, in the afternoon of Tuesday, 13 June, the beams were dumped, marking a break in a successful period of luminosity production to switch to a busy and tightly scheduled machine development (MD) programme, with no fewer than 14 different topics to cover, including studies on operating crystal collimators during the energy ramp and beam response, analyses of the diamond-detector-based beam-loss monitors, beam dynamics to better understand slow beam degradation from electron cloud effects, and beam instability measurements with different bunch intensities. In addition, time was allocated to set up cycles and beams for future physics runs that are scheduled after the technical stop.
For each MD, a procedure is drawn up by the proponents, detailing the goals of the MD and the required beam parameters and machine settings. These procedures are then scrutinised by the LHC Studies Working Group (LSWG) and restricted Machine Protection Panel (rMPP) before the topics are selected and scheduled in the MD slot planned in the yearly LHC schedule. Final approval is then given by the LHC Machine Committee (LMC). Although these MDs take time out of potential physics time, they are very valuable in order to better understand the machine and beam behaviour with a view to increasing beam performance not only during Run 3, but also post-LS3, for the HL-LHC era. One could say that they are a worthwhile investment for future luminosity production.
As I write, the machine is in the hands of the Technical Coordination team (EN department) to carry out the many technical stop (TS) activities on the entire LHC and in the experimental caverns. Of the many planned activities, two were already mentioned in the Accelerator Report of 6 April. The first is the reinstallation of the crystal collimator that broke and had to be removed from the ring during the last phase of hardware commissioning at the end of March. This activity is the reason why the TS was extended by a day – to complete the bake-out, pump-down and hardware tests of the crystal collimator. The second activity is the preventive replacement of the two rupture discs installed in April by two discs that have passed the recent pressure test.
The plan is that cryogenic conditions will be restored in the afternoon of Friday, 23 June; the LHC will then be handed back to the Operations team (BE department) at 16.00 to restart all the subsystems. However, the beam will remain off until the end of the afternoon of Saturday, 24 June in order to finalise the crystal collimator reinstallation. Once that is completed, beam operation will be re-established, initially for special physics runs and later for luminosity production.
The (preliminary) outcome of the MD studies will be presented at the LSWG on Tuesday, 27 June – an opportunity to discuss and gain a greater understanding of the machine and beam dynamics with a view to keeping the LHC’s performance strong and increasingly efficient.
anschaef Thu, 06/22/2023 - 10:25 Byline Rende Steerenberg Publication Date Tue, 06/20/2023 - 10:16CMS honours its 2022 Award and PhD Thesis Award winners
CMS PhD Thesis Award winners 2022
Every year, the CMS collaboration recognises the outstanding achievements of young scientists through this award, highlighting the exceptional contributions made by doctoral researchers in advancing the field of high-energy physics.
From the 32 nominations received this year, three winners were selected by the committee: Angira Rastogi, Willem Verbeke and David Walter.
The 32 nominees for this award had to defend their theses between 1 November 2021 and 31 October 2022. Theses covering various aspects of CMS-related work, including physics analysis, simulation, computing, detector development and engineering, were eligible for nomination. The CMS Thesis Award Committee, consisting of 30 scientists, evaluated the theses based on their content, originality and clarity of writing.
Read more on the CMS collaboration’s website.
CMS award winners 2022 (Image: CERN)CMS Award 2022
Every year, the CMS Award Committee honours some of the CMS collaboration’s members for their outstanding work and dedication to the CMS subdetectors. Nominations can be made by any CMS member, for work in a variety of fields, ranging from detector systems and coordination to outreach.
Two special prizes were awarded in 2022, one in memory of Meenakshi Narain and one to the ECAL team that repaired the leak in the ECAL endcaps. In total, sixty awardees were recognised for their remarkable contribution in 2022.
For more information and to consult the list of awardees, visit the CMS collaboration’s website.
thortala Wed, 06/21/2023 - 11:12 Byline CMS collaboration Publication Date Wed, 06/21/2023 - 11:10CMS honours its 2022 Award and PhD Thesis Award winners
CMS PhD Thesis Award winners 2022
Every year, the CMS collaboration recognises the outstanding achievements of young scientists through this award, highlighting the exceptional contributions made by doctoral researchers in advancing the field of high-energy physics.
From the 32 nominations received this year, three winners were selected by the committee: Angira Rastogi, Willem Verbeke and David Walter.
The 32 nominees for this award had to defend their theses between 1 November 2021 and 31 October 2022. Theses covering various aspects of CMS-related work, including physics analysis, simulation, computing, detector development and engineering, were eligible for nomination. The CMS Thesis Award Committee, consisting of 30 scientists, evaluated the theses based on their content, originality and clarity of writing.
Read more on the CMS collaboration’s website.
CMS award winners 2022 (Image: CERN)CMS Award 2022
Every year, the CMS Award Committee honours some of the CMS collaboration’s members for their outstanding work and dedication to the CMS subdetectors. Nominations can be made by any CMS member, for work in a variety of fields, ranging from detector systems and coordination to outreach.
Two special prizes were awarded in 2022, one in memory of Meenakshi Narain and one to the ECAL team that repaired the leak in the ECAL endcaps. In total, sixty awardees were recognised for their remarkable contribution in 2022.
For more information and to consult the list of awardees, visit the CMS collaboration’s website.
thortala Wed, 06/21/2023 - 11:12 Byline CMS collaboration Publication Date Wed, 06/21/2023 - 11:10LHCb celebrates prizewinners
LHCb awarded its annual prizes at its recent collaboration week. As usual, prizes were awarded for outstanding contributions made by early-career scientists and for the best PhD theses. In addition, for the first time, awards were given for outstanding technical contributions to LHCb. The final industry award for contributions to LHCb Upgrade I was also presented.
The following early-career scientists won prizes for their outstanding contributions:
- Abhijit Mathad, for his development of an offline analysis tool;
- Christina Agapopoulou and Marian Stahl, for their contributions to the high-level trigger software;
- Edoardo Franzoso and Gary Robertson, for their commissioning work on the RICH detector;
- Florian Reiss, Sophie Hollitt, Jake Reich and Biljana Mitreska, for their contributions to the alignment of the detector;
- Giovanni Bassi, for the implementation of FPGA-based VELO clustering.
The following collaboration members won awards for their outstanding technical contributions, in the category’s inaugural year:
- Pascal Sainvitu, for his work on the construction and installation of all LHCb subdetectors;
- Karol Sawczuk, for his contributions to the operation of the Data Centre;
- Kevin McCormick, for his activities on the construction of the VELO detector;
- Petr Gorbounov, Dimitra Andreou, Federico de Benedetti and Mark Tobin, for their efforts on the construction and installation of the UT detector;
- Rodolphe Gonzales, Norbert Adjadj, Magali Magne, Christophe Insa and Andreas Zosgornik, for their contributions to the construction and installation of the scintillating fibre detector.
The winners of the 2023 LHCb thesis prize are Saverio Mariani (Fixed-target physics for the LHCb experiment at CERN) and Peter Švihra (Developing a silicon pixel detector for the next-generation LHCb experiment).
The LHCb industry award, which recognises excellence in collaborations between companies and institutes, was presented to the German company ADCO for their production of carbon composite components for the scintillating fibre detector. Michael König, Herbert Schneider and Martin Solowski represented the company at CERN to receive their trophy.
Many congratulations to all the winners!
thortala Wed, 06/21/2023 - 11:02 Byline LHCb collaboration Publication Date Wed, 06/21/2023 - 10:56LHCb celebrates prizewinners
LHCb awarded its annual prizes at its recent collaboration week. As usual, prizes were awarded for outstanding contributions made by early-career scientists and for the best PhD theses. In addition, for the first time, awards were given for outstanding technical contributions to LHCb. The final industry award for contributions to LHCb Upgrade I was also presented.
The following early-career scientists won prizes for their outstanding contributions:
- Abhijit Mathad, for his development of an offline analysis tool;
- Christina Agapopoulou and Marian Stahl, for their contributions to the high-level trigger software;
- Edoardo Franzoso and Gary Robertson, for their commissioning work on the RICH detector;
- Florian Reiss, Sophie Hollitt, Jake Reich and Biljana Mitreska, for their contributions to the alignment of the detector;
- Giovanni Bassi, for the implementation of FPGA-based VELO clustering.
The following collaboration members won awards for their outstanding technical contributions, in the category’s inaugural year:
- Pascal Sainvitu, for his work on the construction and installation of all LHCb subdetectors;
- Karol Sawczuk, for his contributions to the operation of the Data Centre;
- Kevin McCormick, for his activities on the construction of the VELO detector;
- Petr Gorbounov, Dimitra Andreou, Federico de Benedetti and Mark Tobin, for their efforts on the construction and installation of the UT detector;
- Rodolphe Gonzales, Norbert Adjadj, Magali Magne, Christophe Insa and Andreas Zosgornik, for their contributions to the construction and installation of the scintillating fibre detector.
The winners of the 2023 LHCb thesis prize are Saverio Mariani (Fixed-target physics for the LHCb experiment at CERN) and Peter Švihra (Developing a silicon pixel detector for the next-generation LHCb experiment).
The LHCb industry award, which recognises excellence in collaborations between companies and institutes, was presented to the German company ADCO for their production of carbon composite components for the scintillating fibre detector. Michael König, Herbert Schneider and Martin Solowski represented the company at CERN to receive their trophy.
Many congratulations to all the winners!
thortala Wed, 06/21/2023 - 11:02 Byline LHCb collaboration Publication Date Wed, 06/21/2023 - 10:56A diverse meeting for a diverse fire brigade
On 12 and 13 June, the CERN Fire and Rescue service (CFRS) hosted the 18th meeting of the Commission for Women in Fire and Rescue Services of the CTIF (Comité technique international de prévention et d’extinction de feu), an international association of firefighters.
The CTIF was founded in 1900 with the aim to better understand and continuously improve working conditions for firefighters through ongoing dialogue, analysis and sharing of lessons learned from incidents, accidents and fires throughout the world. Its membership spans 38 countries. The CTIF publishes scientific research, articles and reports. It operates through various commissions, working groups, events and seminars.
The first Women’s Committee of CTIF was formed in 1912. Its activities were interrupted by the First World War and it was not reformed until exactly 100 years later, in 2012, when the Commission for Women in Fire and Rescue Services was created to increase the participation of women in the field, share good practice and research and work on issues regarding gender and equal opportunities. The Commission has addressed, inter alia, harassment, maternity and pregnancy-related practices, and equipment issues.
Fifteen representatives of the Commission, hailing from more than 10 different countries, came to CERN to share best practices and exchange views on the challenges of promoting diversity in the field. The Commission’s decision to select Switzerland and, in particular, CERN as the location for their meeting was inspired by the 2022 CFRS recruitment campaign for firefighters and fire officers that resulted in perfect gender parity: the CFRS hired four women and four men. The combined efforts of the CERN Fire and Rescue service, the HSE communications team, IR-ECO and HR on the one hand, and CTIF on the other hand to increase the number of female applications contributed to this result.
As illustrated by their joint hosting of this event, HSE, the CFRS and HR hope to continue their collaboration in order to maintain this momentum for future recruitment campaigns. Beyond being aligned with CERN policy, the CFRS and the leaders of the HSE unit strongly believe in establishing a diverse and gender-balanced workforce.
The event also included a tour of CERN and, in particular, of the CFRS premises, following which the experienced CTIF experts from all over the world provided valuable feedback on steps the CFRS could take to improve and enhance its operations.
thortala Wed, 06/21/2023 - 09:33 Publication Date Wed, 06/21/2023 - 09:33A diverse meeting for a diverse fire brigade
On 12 and 13 June, the CERN Fire and Rescue service (CFRS) hosted the 18th meeting of the Commission for Women in Fire and Rescue Services of the CTIF (Comité technique international de prévention et d’extinction de feu), an international association of firefighters.
The CTIF was founded in 1900 with the aim to better understand and continuously improve working conditions for firefighters through ongoing dialogue, analysis and sharing of lessons learned from incidents, accidents and fires throughout the world. Its membership spans 38 countries. The CTIF publishes scientific research, articles and reports. It operates through various commissions, working groups, events and seminars.
The first Women’s Committee of CTIF was formed in 1912. Its activities were interrupted by the First World War and it was not reformed until exactly 100 years later, in 2012, when the Commission for Women in Fire and Rescue Services was created to increase the participation of women in the field, share good practice and research and work on issues regarding gender and equal opportunities. The Commission has addressed, inter alia, harassment, maternity and pregnancy-related practices, and equipment issues.
Fifteen representatives of the Commission, hailing from more than 10 different countries, came to CERN to share best practices and exchange views on the challenges of promoting diversity in the field. The Commission’s decision to select Switzerland and, in particular, CERN as the location for their meeting was inspired by the 2022 CFRS recruitment campaign for firefighters and fire officers that resulted in perfect gender parity: the CFRS hired four women and four men. The combined efforts of the CERN Fire and Rescue service, the HSE communications team, IR-ECO and HR on the one hand, and CTIF on the other hand to increase the number of female applications contributed to this result.
As illustrated by their joint hosting of this event, HSE, the CFRS and HR hope to continue their collaboration in order to maintain this momentum for future recruitment campaigns. Beyond being aligned with CERN policy, the CFRS and the leaders of the HSE unit strongly believe in establishing a diverse and gender-balanced workforce.
The event also included a tour of CERN and, in particular, of the CFRS premises, following which the experienced CTIF experts from all over the world provided valuable feedback on steps the CFRS could take to improve and enhance its operations.
thortala Wed, 06/21/2023 - 09:33 Publication Date Wed, 06/21/2023 - 09:33Joan Heemskerk wins CERN’s Collide Copenhagen residency award
Following an international open call launched in collaboration with Copenhagen Contemporary in March, Arts at CERN announced today that Dutch artist Joan Heemskerk is the winner of the first Collide Copenhagen residency award.
Collide is the flagship programme of Arts at CERN, which invites artists worldwide from all creative disciplines to submit proposals for a research-led residency grounded on interactions with CERN’s scientific community. The eleventh edition of Collide, and the first of Collide Copenhagen, attracted 592 project proposals from 90 different countries.
Referencing Tim Berners-Lee’s proposal at CERN that all scientists should be able to exchange ideas, Joan Heemskerk’s project, Alice & Bob after Clay +=-> Hello, world!, seeks to develop a new universal language. Through a re-assessment of the cryptographic characters Alice and Bob, the material clay and the computer programme Hello, World!, the produced message, in the form of a light-beam or a radio-signal or something else entirely, would transcend galactic and life-form boundaries.
Joan Heemskerk will complete a two-month residency, which will be split between CERN and Copenhagen Contemporary and dedicated to artistic research and exploration. She will work side by side with physicists, engineers and laboratory staff.
With the support of the curatorial teams of Arts at CERN and Copenhagen Contemporary, the residency will be followed by a phase of designing and producing a new artwork that will become part of an exhibition at Copenhagen Contemporary in 2025, which will examine the impact of technology on humanity.
“CERN has a long history of innovating ideas and is a unique environment for developing new forms of science and art. It fits within the mission of Arts at CERN to welcome an artist who has continually challenged our collective understanding and imagination of the digital realm. We are delighted to support Joan Heemskerk in exploring the possibility of a new language, in dialogue and with the support of our community”, says Mónica Bello, head of Arts at CERN.
“At Copenhagen Contemporary we regard artists as primary investigators of contemporary culture. As a pioneer of digitally based art, Joan Heemskerk has challenged our notions of technology from the early days of the internet – and we are beyond excited to work with her on a new project”, says Marie Laurberg, director of Copenhagen Contemporary.
About Joan Heemskerk
Joan Heemskerk works in photography, video, software, games, websites, performance and installations. She is a member of the art collective JODI, which pioneered web-based art in the mid-1990s. Their practice investigates conventions of the internet, computer programmes and video games, disrupting the languages of these systems: from visual aesthetics to interface elements, from codes and features to errors and viruses. They challenge the relationship between computer technology and users by subverting our expectations about the functionalities and conventions of the systems that we depend upon in our everyday lives.
About the jury
The jury consisted of Mónica Bello, curator and head of Arts at CERN; Irene Campolmi, curator and researcher; Vitor Cardoso, professor of Physics and Villum investigator at the Niels Bohr Institute, University of Copenhagen; Marie Laurberg, director of Copenhagen Contemporary; Filipa Ramos, PhD, writer, curator and lecturer at the Institute Art Gender Nature, Basel Academy of Art and Design; Iliana Tatsi, curator at CERN Science Gateway exhibitions; and Helga Timko, accelerator physicist at the LHC and member of the CERN Cultural Board.
Joan Heemskerk wins CERN’s Collide Copenhagen residency award
Following an international open call launched in collaboration with Copenhagen Contemporary in March, Arts at CERN announced today that Dutch artist Joan Heemskerk is the winner of the first Collide Copenhagen residency award.
Collide is the flagship programme of Arts at CERN, which invites artists worldwide from all creative disciplines to submit proposals for a research-led residency grounded on interactions with CERN’s scientific community. The eleventh edition of Collide, and the first of Collide Copenhagen, attracted 592 project proposals from 90 different countries.
Referencing Tim Berners-Lee’s proposal at CERN that all scientists should be able to exchange ideas, Joan Heemskerk’s project, Alice & Bob after Clay +=-> Hello, world!, seeks to develop a new universal language. Through a re-assessment of the cryptographic characters Alice and Bob, the material clay and the computer programme Hello, World!, the produced message, in the form of a light-beam or a radio-signal or something else entirely, would transcend galactic and life-form boundaries.
Joan Heemskerk will complete a two-month residency, which will be split between CERN and Copenhagen Contemporary and dedicated to artistic research and exploration. She will work side by side with physicists, engineers and laboratory staff.
With the support of the curatorial teams of Arts at CERN and Copenhagen Contemporary, the residency will be followed by a phase of designing and producing a new artwork that will become part of an exhibition at Copenhagen Contemporary in 2025, which will examine the impact of technology on humanity.
“CERN has a long history of innovating ideas and is a unique environment for developing new forms of science and art. It fits within the mission of Arts at CERN to welcome an artist who has continually challenged our collective understanding and imagination of the digital realm. We are delighted to support Joan Heemskerk in exploring the possibility of a new language, in dialogue and with the support of our community”, says Mónica Bello, head of Arts at CERN.
“At Copenhagen Contemporary we regard artists as primary investigators of contemporary culture. As a pioneer of digitally based art, Joan Heemskerk has challenged our notions of technology from the early days of the internet – and we are beyond excited to work with her on a new project”, says Marie Laurberg, director of Copenhagen Contemporary.
About Joan Heemskerk
Joan Heemskerk works in photography, video, software, games, websites, performance and installations. She is a member of the art collective JODI, which pioneered web-based art in the mid-1990s. Their practice investigates conventions of the internet, computer programmes and video games, disrupting the languages of these systems: from visual aesthetics to interface elements, from codes and features to errors and viruses. They challenge the relationship between computer technology and users by subverting our expectations about the functionalities and conventions of the systems that we depend upon in our everyday lives.
About the jury
The jury consisted of Mónica Bello, curator and head of Arts at CERN; Irene Campolmi, curator and researcher; Vitor Cardoso, professor of Physics and Villum investigator at the Niels Bohr Institute, University of Copenhagen; Marie Laurberg, director of Copenhagen Contemporary; Filipa Ramos, PhD, writer, curator and lecturer at the Institute Art Gender Nature, Basel Academy of Art and Design; Iliana Tatsi, curator at CERN Science Gateway exhibitions; and Helga Timko, accelerator physicist at the LHC and member of the CERN Cultural Board.
Computer Security: ChatNoSCRCY
Life has become easier. Instead of your former internet buddy, the good old search engine, giving you reams of answers to your search, the new hype on the market is “ChatGPT”, which produces for you the one and only best answer out there amalgamed from its vast training set of data. Inspiration for your job application to CERN? There you go. Quickly dashing off a travel request in Swahili? Karibu*. A love letter in poetic French? Voilà, mon cœur. Producing a code snippet for a software you need? {int return(1)}. Even creating your “own” photographic artworks has become as easy as pie ─ not to mention films and music in the near future. Deepfakes, anyone?
So, life becomes easier. And more confusing. The truth is becoming blurred, as ChatGPT’s answers are only as good as the information provided by its data set. So, beware: your application form, love letter or program code might not produce the quality and result you expected. Common sense, gut feelings, human intelligence and thinking for yourself are your best friends when it comes to assessing ChatGPT’s “truth” (see “Hallucination”).
But, apart from these sociological problems, there are also certain security and privacy aspects to consider. In ChatGPT there is no secrecy!
- Data exposure: Depending on who runs your ChatGPT platform, everything you type in could become mangled into other answers, eventually disclosing some confidential stuff you don’t want to see in the public domain (we’re aware of some CERN developers posting their code snippets into ChatGPT and asking it to find the bug – these might have included passwords or other secrets).
- Data disclosure during training: Any AI needs training. This training is based on lots and lots of training data which may or may not be considered sensitive/restricted. If adequate protection means are omitted, when the AI training mangles different trainings sets, including those of third parties, and if all the tenants are not well separated, your data might make it into the public domain. To third-party tenants or to creative users. It wouldn’t be the first time that a company leaked data through inadequate data protection means.
- Data leakage: Even if you’ve secured the confidentiality of your training data, when it is exposed to third parties for usage or “questioning”, clever people might be able to extract some confidential information by clever questioning.
- Copyright: The training set, and your subsequent result, might be based on copyrighted material. Currently, it is a legal grey area whether or not your new artwork, sound bite or video is subject to those copyrights and you should pay compensation to the owners of the pieces in question.
- Poisoning: This is where an attacker (or an inexperienced AI trainer) manipulates the training sets in such a way that the results are flawed or biased.
- Cheating: Finally, to the chagrin of schoolchildren and students, ChatGPT is a perfect tool to produce results that are not your own. Not your own painting. Not your own homework. Not your own paper. While it might be difficult to spot the real origin today, time may reveal that some authors plagiarised their work.
And, of course, like any other (cloud) software, there are the same computer security and privacy risks that require the same protective means: access control, active system maintenance and patching, encryption and data protection, back-up and disaster recovery, monitoring and logging, etc.
So, like with any new technology, and while ChatGPT definitely has its merits and might well be the next game-changer in IT, it also comes with certain risks linked to copyright, privacy and SeCReCY. Make sure the benefits outweigh the potential harm!
* "Karibu": a Swahili word that in English would mean "don't hesitate" or "please".
_____
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.
anschaef Tue, 06/20/2023 - 11:11 Byline Computer Security team Publication Date Tue, 06/20/2023 - 11:06Computer Security: ChatNoSCRCY
Life has become easier. Instead of your former internet buddy, the good old search engine, giving you reams of answers to your search, the new hype on the market is “ChatGPT”, which produces for you the one and only best answer out there amalgamed from its vast training set of data. Inspiration for your job application to CERN? There you go. Quickly dashing off a travel request in Swahili? Karibu*. A love letter in poetic French? Voilà, mon cœur. Producing a code snippet for a software you need? {int return(1)}. Even creating your “own” photographic artworks has become as easy as pie ─ not to mention films and music in the near future. Deepfakes, anyone?
So, life becomes easier. And more confusing. The truth is becoming blurred, as ChatGPT’s answers are only as good as the information provided by its data set. So, beware: your application form, love letter or program code might not produce the quality and result you expected. Common sense, gut feelings, human intelligence and thinking for yourself are your best friends when it comes to assessing ChatGPT’s “truth” (see “Hallucination”).
But, apart from these sociological problems, there are also certain security and privacy aspects to consider. In ChatGPT there is no secrecy!
- Data exposure: Depending on who runs your ChatGPT platform, everything you type in could become mangled into other answers, eventually disclosing some confidential stuff you don’t want to see in the public domain (we’re aware of some CERN developers posting their code snippets into ChatGPT and asking it to find the bug – these might have included passwords or other secrets).
- Data disclosure during training: Any AI needs training. This training is based on lots and lots of training data which may or may not be considered sensitive/restricted. If adequate protection means are omitted, when the AI training mangles different trainings sets, including those of third parties, and if all the tenants are not well separated, your data might make it into the public domain. To third-party tenants or to creative users. It wouldn’t be the first time that a company leaked data through inadequate data protection means.
- Data leakage: Even if you’ve secured the confidentiality of your training data, when it is exposed to third parties for usage or “questioning”, clever people might be able to extract some confidential information by clever questioning.
- Copyright: The training set, and your subsequent result, might be based on copyrighted material. Currently, it is a legal grey area whether or not your new artwork, sound bite or video is subject to those copyrights and you should pay compensation to the owners of the pieces in question.
- Poisoning: This is where an attacker (or an inexperienced AI trainer) manipulates the training sets in such a way that the results are flawed or biased.
- Cheating: Finally, to the chagrin of schoolchildren and students, ChatGPT is a perfect tool to produce results that are not your own. Not your own painting. Not your own homework. Not your own paper. While it might be difficult to spot the real origin today, time may reveal that some authors plagiarised their work.
And, of course, like any other (cloud) software, there are the same computer security and privacy risks that require the same protective means: access control, active system maintenance and patching, encryption and data protection, back-up and disaster recovery, monitoring and logging, etc.
So, like with any new technology, and while ChatGPT definitely has its merits and might well be the next game-changer in IT, it also comes with certain risks linked to copyright, privacy and SeCReCY. Make sure the benefits outweigh the potential harm!
_____
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.
anschaef Tue, 06/20/2023 - 11:11 Byline Computer Security team Publication Date Tue, 06/20/2023 - 11:06Connecting the small and the large scales
Gravitational waves, like the discovery of the Higgs boson in 2012, have made their mark on a decade of extraordinary discoveries in physics. Unlike gravity, which is created when massive objects leave their mark in the fabric of spacetime, gravitational waves are very weak ripples in spacetime that are caused by gravity-accelerated masses. So far, researchers have been able to detect the gravitational waves produced by the melting together of very heavy objects, such as black holes or neutron stars. When this happens, these echoes from the past reverberate through the whole Universe and finally reach Earth, allowing us to piece together what happened millions of light-years ago.
Current gravitational-wave observatories can only detect a few gravitational waves as they cover just a narrow spectrum of the whole range of wavelengths that are emitted. Future gravitational-wave observatories, such as the Einstein Telescope, a CERN-recognised experiment, need to be larger in order to search for a larger bandwidth of gravitational waves that could tell us more about the Universe.
A key ingredient of future gravitational-wave observatories is ultra-high vacuum technology. As the world-leading R&D facility for applications in this field, CERN is one of the few places where people know how to build very long ultra-high vacuum systems. CERN’s decade-long experience of installing complex and ultra-pure vacuum systems underground is an additional benefit for the Einstein Telescope since it will be installed at least 200 metres below the Earth’s surface. The lead institutes of the Einstein Telescope Collaboration therefore entered into a collaboration agreement with CERN in 2022. Building on this agreement, a workshop was held in March 2023 dedicated to brainstorming on how these systems might look and which materials would work best. The Collaboration hopes to complete a prototype vacuum pipe by the end of 2025. The findings from the workshop will help to reduce not only the cost of building the Einstein Telescope but also potentially the cost of future accelerators.
“The expected sensitivity of the Einstein Telescope will be at least a factor of ten times that of Ligo-Virgo,” says Michele Punturo, who began his career as a physicist at CERN and is now the spokesperson of the Collaboration. “Its low-frequency sensitivity will allow us to detect intermediate mass black holes.”
The Einstein Telescope is designed to measure gravitational waves ten times more precisely than existing gravitational-wave detectors and will complement future space-based gravitational wave detectors. The experiment will send a laser beam down into the 120-km-long triangular-shaped tunnel. This beam will be then split into two beams, which are reflected by mirrors. The length of the tunnel has been chosen so that the two laser beams precisely cancel each other. If a gravitational wave crosses the laser signal, it will be perturbed, thus leaving behind an imprint of itself. The nature of this imprint will provide researchers with information about the event that created the gravitational wave in the first place.
Due to the high precision of the signal, the vacuum system in which the laser operates needs to be not only ultra-pure, but also free from vibrations as well as electromagnetic contamination, since both can mimic the signal from the incoming gravitational wave.
Another potential source of modification of the gravitational wave frequency is dark matter, the elusive form of matter that seems to make up most of our Universe. Theorists are already working on models to verify whether a recorded signal could be influenced by dark matter. These searches would complement the searches for dark matter that are currently being carried out in collider and fixed-target experiments at CERN.
Watch a video with Michele Punturo, the spokesperson for the Einstein Telescope Collaboration:
Video interview with Michele Punturo, spokesperson for the Einstein Telescope Collaboration (Video: CERN)
Fact box
- The Einstein Telescope became a CERN-recognised experiment on 16 March 2022
- A collaboration agreement with CERN on vacuum technologies was signed in October 2022
- The Einstein Telescope will comprise three nested detectors, each equipped with two interferometers
- The length of each interferometer will be 10 km
- One of the interferometers will detect low-frequency gravitational waves
- The other interferometer will detect high-frequency gravitational waves
- The Einstein Telescope will detect gravitational waves with frequencies of between 1 Hz and 10 000 Hz
Connecting the small and the large scales
Gravitational waves, like the discovery of the Higgs boson in 2012, have made their mark on a decade of extraordinary discoveries in physics. Unlike gravity, which is created when massive objects leave their mark in the fabric of spacetime, gravitational waves are very weak ripples in spacetime that are caused by gravity-accelerated masses. So far, researchers have been able to detect the gravitational waves produced by the melting together of very heavy objects, such as black holes or neutron stars. When this happens, these echoes from the past reverberate through the whole Universe and finally reach Earth, allowing us to piece together what happened millions of light-years ago.
Current gravitational-wave observatories can only detect a few gravitational waves as they cover just a narrow spectrum of the whole range of wavelengths that are emitted. Future gravitational-wave observatories, such as the Einstein Telescope, a CERN-recognised experiment, need to be larger in order to search for a larger bandwidth of gravitational waves that could tell us more about the Universe.
A key ingredient of future gravitational-wave observatories is ultra-high vacuum technology. As the world-leading R&D facility for applications in this field, CERN is one of the few places where people know how to build very long ultra-high vacuum systems. CERN’s decade-long experience of installing complex and ultra-pure vacuum systems underground is an additional benefit for the Einstein Telescope since it will be installed at least 200 metres below the Earth’s surface. The lead institutes of the Einstein Telescope Collaboration therefore entered into a collaboration agreement with CERN in 2022. Building on this agreement, a workshop was held in March 2023 dedicated to brainstorming on how these systems might look and which materials would work best. The Collaboration hopes to complete a prototype vacuum pipe by the end of 2025. The findings from the workshop will help to reduce not only the cost of building the Einstein Telescope but also potentially the cost of future accelerators.
“The expected sensitivity of the Einstein Telescope will be at least a factor of ten times that of Ligo-Virgo,” says Michele Punturo, who began his career as a physicist at CERN and is now the spokesperson of the Collaboration. “Its low-frequency sensitivity will allow us to detect intermediate mass black holes.”
The Einstein Telescope is designed to measure gravitational waves ten times more precisely than existing gravitational-wave detectors and will complement future space-based gravitational wave detectors. The experiment will send a laser beam down into the 120-km-long triangular-shaped tunnel. This beam will be then split into two beams, which are reflected by mirrors. The length of the tunnel has been chosen so that the two laser beams precisely cancel each other. If a gravitational wave crosses the laser signal, it will be perturbed, thus leaving behind an imprint of itself. The nature of this imprint will provide researchers with information about the event that created the gravitational wave in the first place.
Due to the high precision of the signal, the vacuum system in which the laser operates needs to be not only ultra-pure, but also free from vibrations as well as electromagnetic contamination, since both can mimic the signal from the incoming gravitational wave.
Another potential source of modification of the gravitational wave frequency is dark matter, the elusive form of matter that seems to make up most of our Universe. Theorists are already working on models to verify whether a recorded signal could be influenced by dark matter. These searches would complement the searches for dark matter that are currently being carried out in collider and fixed-target experiments at CERN.
Watch a video with Michele Punturo, the spokesperson for the Einstein Telescope Collaboration:
Video interview with Michele Punturo, spokesperson for the Einstein Telescope Collaboration (Video: CERN)
Fact box
- The Einstein Telescope became a CERN-recognised experiment on 16 March 2022
- A collaboration agreement with CERN on vacuum technologies was signed in October 2022
- The Einstein Telescope will comprise three nested detectors, each equipped with two interferometers
- The length of each interferometer will be 10 km
- One of the interferometers will detect low-frequency gravitational waves
- The other interferometer will detect high-frequency gravitational waves
- The Einstein Telescope will detect gravitational waves with frequencies of between 1 Hz and 10 000 Hz
Preparing for the next era of neutrino research
At CERN’s Neutrino Platform on the Laboratory’s Prévessin site in France sit two large boxes encased in a red grating. Inside these boxes are vast chambers surrounded by shiny stainless steel. The boxes are the cryostat modules of the ProtoDUNE experiment. Despite their large size, they are tiny in comparison to the future size of their successors for the Deep Underground Neutrino Experiment (DUNE), a vast neutrino experiment currently being built in the USA. The Neutrino Platform also houses an assembly station for the Tokai to Kamioka (T2K) experiment, another vast neutrino facility in Japan.
Neutrinos are one of the least well-known types of particles in the Standard Model. Although they are the most abundant massive particles in the Universe, neutrinos have very small mass and only interact through gravity and the weak nuclear force, making them difficult to study. However, neutrinos may hold the key to fundamental questions such as why the Universe is filled with matter and not antimatter. So-called long-baseline neutrino-oscillation experiments could help to answer these questions by studying how neutrinos change their “flavour”, or oscillate, as they travel over a long distance, or baseline.
Once built in the USA, DUNE will send a beam of neutrinos from Fermi National Accelerator Laboratory (Fermilab) near Chicago, Illinois, over a distance of more than 1300 kilometres through the Earth to neutrino detectors located 1.5 km underground at the Sanford Underground Research Facility (SURF) in Sanford, South Dakota. The detectors themselves are vast cryostats filled with liquid argon. When neutrinos interact with the argon, which happens only occasionally, this ionises the argon atoms. The loose electrons and argon atoms are then separated by an electric field that runs through the detector. The shape of the electron cloud created by the ionisation is conserved and detected by the electrode sensors located on the walls of the cryostat. This produces images of the trajectories of particles created by the neutrino interactions, allowing physicists to determine the neutrinos’ properties such as their flavour and mass. These detectors, which use a combination of electric fields passing through a volume of fluid, are called time projection chambers.
Aerial view of the ProtoDUNE cryostats (Image: CERN)Back to Prévessin. In 2018, ProtoDUNE began its first run. Both cryostats were tested until 2021, the first in a single-phase configuration of the experiment (ProtoDUNE-SP) and the second in a dual-phase configuration (ProtoDUNE-DP). The first run recorded over four million particle interactions, providing important information about the technology challenges associated with DUNE, and demonstrated that the full experiment was ready for construction. Since January 2023, the Neutrino Platform has been preparing for ProtoDUNE’s second run. The two cryostats are both now single-phase, one measuring the drift of electrons across a horizontal electric field (ProtoDUNE-HD) and the other across a vertical field (ProtoDUNE-VD). Scientists will use this second run to determine how these technologies should be implemented in DUNE. The two cryostats will be filled with liquid argon soon and will begin taking data at the beginning of next year.
The Neutrino Platform also hosts the assembly platform for the T2K experiment. T2K has already been operating for over a decade in Japan, sending beams of neutrinos from Tokai on the East coast over a distance of 295 km to the Super-Kamiokande detector in Kamioka, close to the West coast. In 2011, T2K provided the first evidence of muon neutrino-to-electron-neutrino oscillations and has since hinted at neutrino matter–antimatter asymmetry. One of its detectors, ND280, is currently undergoing an upgrade, which the T2K collaboration hopes will allow it to increase the efficiency of the experiment and more accurately reconstruct the neutrino oscillations.
The ND280 upgrade consists of multiple subdetectors, many of which were assembled and tested at the Neutrino Platform. These include new time projection chambers, one of which is now currently taking cosmic data at CERN. Other types of subdetectors are either already installed or ready to be shipped to Japan after assembly at the Neutrino Platform. As well as individual subdetectors, the new gas system for the whole ND280 detector was completely developed and tested at CERN. Still to be completed is the assembly of another time projection chamber, and its shipment to and installation at T2K. The ND280 upgrade is projected to be finalised in 2023. It is planned that the upgraded ND280 will also serve in the next generation long-baseline neutrino oscillation experiment known as Hyper-Kamiokande (HyperK).
A time projection chamber for the ND280 detector, built at CERN for the T2K experiment (Image: CERN)Want to find out more about neutrinos and the DUNE experiment? Join CERN for a livestream in collaboration with Fermilab and the Sanford Underground Research Facility (SURF) at 6 p.m. CEST on 15 June.
ndinmore Tue, 06/13/2023 - 10:08 Byline Naomi Dinmore Publication Date Tue, 06/13/2023 - 09:57Preparing for the next era of neutrino research
At CERN’s Neutrino Platform on the Laboratory’s Prévessin site in France sit two large boxes encased in a red grating. Inside these boxes are vast chambers surrounded by shiny stainless steel. The boxes are the cryostat modules of the ProtoDUNE experiment. Despite their large size, they are tiny in comparison to the future size of their successors for the Deep Underground Neutrino Experiment (DUNE), a vast neutrino experiment currently being built in the USA. The Neutrino Platform also houses an assembly station for the Tokai to Kamioka (T2K) experiment, another vast neutrino facility in Japan.
Neutrinos are one of the least well-known types of particles in the Standard Model. Although they are the most abundant massive particles in the Universe, neutrinos have very small mass and only interact through gravity and the weak nuclear force, making them difficult to study. However, neutrinos may hold the key to fundamental questions such as why the Universe is filled with matter and not antimatter. So-called long-baseline neutrino-oscillation experiments could help to answer these questions by studying how neutrinos change their “flavour”, or oscillate, as they travel over a long distance, or baseline.
Once built in the USA, DUNE will send a beam of neutrinos from Fermi National Accelerator Laboratory (Fermilab) near Chicago, Illinois, over a distance of more than 1300 kilometres through the Earth to neutrino detectors located 1.5 km underground at the Sanford Underground Research Facility (SURF) in Sanford, South Dakota. The detectors themselves are vast cryostats filled with liquid argon. When neutrinos interact with the argon, which happens only occasionally, this ionises the argon atoms. The loose electrons and argon atoms are then separated by an electric field that runs through the detector. The shape of the electron cloud created by the ionisation is conserved and detected by the electrode sensors located on the walls of the cryostat. This produces images of the trajectories of particles created by the neutrino interactions, allowing physicists to determine the neutrinos’ properties such as their flavour and mass. These detectors, which use a combination of electric fields passing through a volume of fluid, are called time projection chambers.
Aerial view of the ProtoDUNE cryostats (Image: CERN)Back to Prévessin. In 2018, ProtoDUNE began its first run. Both cryostats were tested until 2021, the first in a single-phase configuration of the experiment (ProtoDUNE-SP) and the second in a dual-phase configuration (ProtoDUNE-DP). The first run recorded over four million particle interactions, providing important information about the technology challenges associated with DUNE, and demonstrated that the full experiment was ready for construction. Since January 2023, the Neutrino Platform has been preparing for ProtoDUNE’s second run. The two cryostats are both now single-phase, one measuring the drift of electrons across a horizontal electric field (ProtoDUNE-HD) and the other across a vertical field (ProtoDUNE-VD). Scientists will use this second run to determine how these technologies should be implemented in DUNE. The two cryostats will be filled with liquid argon soon and will begin taking data at the beginning of next year.
The Neutrino Platform also hosts the assembly platform for the T2K experiment. T2K has already been operating for over a decade in Japan, sending beams of nvzheutrinos from Tokai on the East coast over a distance of 295 km to the Super-Kamiokande detector in Kamioka, close to the West coast. In 2011, T2K provided the first evidence of muon neutrino-to-electron-neutrino oscillations and has since hinted at neutrino matter–antimatter asymmetry. One of its detectors, ND280, is currently undergoing an upgrade, which the T2K collaboration hopes will allow it to increase the efficiency of the experiment and more accurately reconstruct the neutrino oscillations.
The ND280 upgrade consists of multiple subdetectors, many of which were assembled and tested at the Neutrino Platform. These include new time projection chambers, one of which is now currently taking cosmic data at CERN. Other types of subdetectors are either already installed or ready to be shipped to Japan after assembly at the Neutrino Platform. As well as individual subdetectors, the new gas system for the whole ND280 detector was completely developed and tested at CERN. Still to be completed is the assembly of another time projection chamber, and its shipment to and installation at T2K. The ND280 upgrade is projected to be finalised in 2023. It is planned that the upgraded ND280 will also serve in the next generation long-baseline neutrino oscillation experiment known as Hyper-Kamiokande (HyperK).
A time projection chamber for the ND280 detector, built at CERN for the T2K experiment (Image: CERN)Want to find out more about neutrinos and the DUNE experiment? Join CERN for a livestream in collaboration with Fermilab and the Sanford Underground Research Facility (SURF) at 6 p.m. CEST on 15 June.
ndinmore Tue, 06/13/2023 - 10:08 Byline Naomi Dinmore Publication Date Tue, 06/13/2023 - 09:57LHCb tightens precision on key measurements of matter–antimatter asymmetry
The Big Bang is thought to have created equal amounts of matter and antimatter, yet the Universe today is made almost entirely of matter, so something must have happened to create this imbalance.
The weak force of the Standard Model of particle physics is known to induce a behavioural difference between matter and antimatter – known as CP symmetry violation – in decays of particles containing quarks, one of the building blocks of matter. But these differences, or asymmetries, are hard to measure and insufficient to explain the matter–antimatter imbalance in the present-day Universe, prompting physicists to both measure precisely the known differences and to look for new ones.
At a seminar held at CERN today, the LHCb collaboration reported how it has measured, more precisely than ever before, two key parameters that determine such matter–antimatter asymmetries.
In 1964, James Cronin and Val Fitch discovered CP symmetry violation through their pioneering experiment at Brookhaven National Laboratory in the US, using decays of particles containing strange quarks. This finding challenged the long-held belief in this symmetry of nature and earned Cronin and Fitch the Nobel Prize in Physics in 1980.
In 2001, the BaBar experiment in the US and the Belle experiment in Japan confirmed the existence of CP violation in decays of beauty mesons, particles with a beauty quark, solidifying our understanding of the nature of this phenomenon. This achievement ignited intense research efforts to further understand the mechanisms behind CP violation. In 2008, Makoto Kobayashi and Toshihide Maskawa received the Nobel Prize in Physics for their theoretical framework that elegantly explained the observed CP violation phenomena.
It its latest studies, using the full dataset recorded by the LHCb detector during the second run of the Large Hadron Collider (LHC), the LHCb collaboration set out to measure with high precision two parameters that determine the amount of CP violation in decays of beauty mesons.
One parameter determines the amount of CP violation in decays of neutral beauty mesons, which are made up of a bottom antiquark and a down quark. This is the same parameter as that measured by the BaBar and Belle experiments in 2001. The other parameter determines the amount of CP violation in decays of strange beauty mesons, which consist of a bottom antiquark and a strange quark.
Specifically, these parameters determine the extent of time-dependent CP violation. This type of CP violation stems from the intriguing quantum interference that occurs when a particle and its antiparticle undergo decay. The particle has the ability to spontaneously transform into its antiparticle and vice versa. As this oscillation takes place, the decays of the particle and antiparticle interfere with each other, leading to a distinctive pattern of CP violation that changes over time. In other words, the amount of CP violation observed depends on the time the particle lives before decaying. This fascinating phenomenon provides physicists with key insights into the fundamental nature of particles and their symmetries.
For both parameters, the new LHCb results, which are more precise than any equivalent result from a single experiment, are in line with the values predicted by the Standard Model.
“These measurements are interpreted within our fundamental theory of particle physics, the Standard Model, improving the precision with which we can determine the difference between the behaviour of matter and antimatter,” explains LHCb spokesperson Chris Parkes. “Through more precise measurements, large improvements have been made in our knowledge. These are key parameters that aid our search for unknown effects from beyond our current theory.”
Future data, from the third run of the LHC and the collider’s planned upgrade, the High-Luminosity LHC, will further tighten the precision on these matter–antimatter asymmetry parameters and perhaps point to new physics phenomena that could help shed light on what is one of the Universe’s best-kept secrets.
Find out more on LHCb's website: precise measurement of the CP-violating phase φs and precise measurement of the unitarity triangle angle β
angerard Tue, 06/13/2023 - 08:17 Publication Date Tue, 06/13/2023 - 12:35
LHCb tightens precision on key measurements of matter–antimatter asymmetry
The Big Bang is thought to have created equal amounts of matter and antimatter, yet the Universe today is made almost entirely of matter, so something must have happened to create this imbalance.
The weak force of the Standard Model of particle physics is known to induce a behavioural difference between matter and antimatter – known as CP symmetry violation – in decays of particles containing quarks, one of the building blocks of matter. But these differences, or asymmetries, are hard to measure and insufficient to explain the matter–antimatter imbalance in the present-day Universe, prompting physicists to both measure precisely the known differences and to look for new ones.
At a seminar held at CERN today, the LHCb collaboration reported how it has measured, more precisely than ever before, two key parameters that determine such matter–antimatter asymmetries.
In 1964, James Cronin and Val Fitch discovered CP symmetry violation through their pioneering experiment at Brookhaven National Laboratory in the US, using decays of particles containing strange quarks. This finding challenged the long-held belief in this symmetry of nature and earned Cronin and Fitch the Nobel Prize in Physics in 1980.
In 2001, the BaBar experiment in the US and the Belle experiment in Japan confirmed the existence of CP violation in decays of beauty mesons, particles with a beauty quark, solidifying our understanding of the nature of this phenomenon. This achievement ignited intense research efforts to further understand the mechanisms behind CP violation. In 2008, Makoto Kobayashi and Toshihide Maskawa received the Nobel Prize in Physics for their theoretical framework that elegantly explained the observed CP violation phenomena.
It its latest studies, using the full dataset recorded by the LHCb detector during the second run of the Large Hadron Collider (LHC), the LHCb collaboration set out to measure with high precision two parameters that determine the amount of CP violation in decays of beauty mesons.
One parameter determines the amount of CP violation in decays of neutral beauty mesons, which are made up of a bottom antiquark and a down quark. This is the same parameter as that measured by the BaBar and Belle experiments in 2001. The other parameter determines the amount of CP violation in decays of strange beauty mesons, which consist of a bottom antiquark and a strange quark.
Specifically, these parameters determine the extent of time-dependent CP violation. This type of CP violation stems from the intriguing quantum interference that occurs when a particle and its antiparticle undergo decay. The particle has the ability to spontaneously transform into its antiparticle and vice versa. As this oscillation takes place, the decays of the particle and antiparticle interfere with each other, leading to a distinctive pattern of CP violation that changes over time. In other words, the amount of CP violation observed depends on the time the particle lives before decaying. This fascinating phenomenon provides physicists with key insights into the fundamental nature of particles and their symmetries.
For both parameters, the new LHCb results, which are more precise than any equivalent result from a single experiment, are in line with the values predicted by the Standard Model.
“These measurements are interpreted within our fundamental theory of particle physics, the Standard Model, improving the precision with which we can determine the difference between the behaviour of matter and antimatter,” explains LHCb spokesperson Chris Parkes. “Through more precise measurements, large improvements have been made in our knowledge. These are key parameters that aid our search for unknown effects from beyond our current theory.”
Future data, from the third run of the LHC and the collider’s planned upgrade, the High-Luminosity LHC, will further tighten the precision on these matter–antimatter asymmetry parameters and perhaps point to new physics phenomena that could help shed light on what is one of the Universe’s best-kept secrets.
Find out more on LHCb's website: precise measurement of the CP-violating phase φs and precise measurement of the unitarity triangle angle β
angerard Tue, 06/13/2023 - 08:17 Publication Date Tue, 06/13/2023 - 12:35
Accelerator Report: Overcoming setbacks, antiprotons return as LHC recovers luminescent brilliance
The Accelerator Report published on 10 May highlighted that the 2023 antiproton physics run was delayed by 50 days (reducing the run to 122 days instead of the 172 initially scheduled) due to a broken magnet in the injection region of the Antiproton Decelerator (AD). Consequently, the beam commissioning of the AD was due to start on 12 June and the delivery of antiprotons to the AD-ELENA experiments on 30 June.
Following the hard work of many experts, the AD operations team received on Friday, 1 June at 11:58 – 12 days earlier than rescheduled – the green light from the AD injection kicker expert: beam could be injected again in the AD ring, signalling the start of the beam commissioning. The AD operations team and the equipment experts rescheduled their activities to focus on the AD beam commissioning in order to bring forward the rescheduled start of physics, reducing the number of lost physics days from 50 to about 40. This is, of course, much welcomed by the AD-ELENA experimental users, who are eagerly awaiting low-energy antiprotons to perform their experiments.
The RF finger module (right-hand side) ensures a low-impedance (low-resistivity) electrical connectivity between the LHC vacuum chambers. When this electrical connection is not good enough, it affects the circulating beam by making it unstable, deteriorating its quality or creating losses that can lead to a beam dump. (Image: CERN)The rest of the LHC injector chain is running well for the LHC and the fixed-target experiments. However, the LHC suffered a temporary dip in luminosity production due to the replacement last week of a radiofrequency (RF) finger module in the machine section located near the ATLAS experiment (Point 1).
In the early evening of Thursday, 25 May, the LHC beam was dumped during acceleration on two consecutive fills. Both beam dumps were triggered by slow local losses* left of Point 1. X-ray imaging investigations and beam-loss studies led to the conclusion that one of the RF finger modules in a warm section was heating up or arcing, degrading the vacuum in that area and causing the slow local beam losses. The luminosity production was interrupted and, during the long Whitsun weekend, various teams intervened in the LHC tunnel to replace the RF finger module (with subsequent vacuum pumping). Already in the morning of Tuesday, 30 May, beams were injected and circulated to check the vacuum conditions. In the evening, a first fill with only 700 bunches per beam, followed by a second fill with 1200 bunches, were used for physics while also conditioning the area of the newly installed RF finger module. In the following days, the intensity ramped up to 2400 bunches and, in a second stage, the intensity per bunch was increased from 1.3x1011 to 1.6x1011 protons per bunch.
Until further notice and pending greater understanding of the cause of the RF finger module fault, the bunch intensity will be limited to 1.6x1011 protons per bunch. By now, the LHC is again filled with the default 2400 bunch filling scheme with 1.55x1011 protons per bunch, producing close to 1 fb-1 per day. As I write, the integrated luminosities for ATLAS and CMS are each 16 fb-1, which is about 5 fb-1 below the target value, but we’re catching up.
____
* “Slow local losses” happen when some beam particles get lost in specific parts of the ring when interacting with the gas molecules in the degraded vacuum. This process takes some time before the threshold to dump the beam is reached.
anschaef Wed, 06/07/2023 - 13:44 Byline Rende Steerenberg Publication Date Tue, 06/06/2023 - 13:27Accelerator Report: Overcoming setbacks, antiprotons return as LHC recovers luminescent brilliance
The Accelerator Report published on 10 May highlighted that the 2023 antiproton physics run was delayed by 50 days (reducing the run to 122 days instead of the 172 initially scheduled) due to a broken magnet in the injection region of the Antiproton Decelerator (AD). Consequently, the beam commissioning of the AD was due to start on 12 June and the delivery of antiprotons to the AD-ELENA experiments on 30 June.
Following the hard work of many experts, the AD operations team received on Friday, 1 June at 11:58 – 12 days earlier than rescheduled – the green light from the AD injection kicker expert: beam could be injected again in the AD ring, signalling the start of the beam commissioning. The AD operations team and the equipment experts rescheduled their activities to focus on the AD beam commissioning in order to bring forward the rescheduled start of physics, reducing the number of lost physics days from 50 to about 40. This is, of course, much welcomed by the AD-ELENA experimental users, who are eagerly awaiting low-energy antiprotons to perform their experiments.
The RF finger module (right-hand side) ensures a low-impedance (low-resistivity) electrical connectivity between the LHC vacuum chambers. When this electrical connection is not good enough, it affects the circulating beam by making it unstable, deteriorating its quality or creating losses that can lead to a beam dump. (Image: CERN)The rest of the LHC injector chain is running well for the LHC and the fixed-target experiments. However, the LHC suffered a temporary dip in luminosity production due to the replacement last week of a radiofrequency (RF) finger module in the machine section located near the ATLAS experiment (Point 1).
In the early evening of Thursday, 25 May, the LHC beam was dumped during acceleration on two consecutive fills. Both beam dumps were triggered by slow local losses* left of Point 1. X-ray imaging investigations and beam-loss studies led to the conclusion that one of the RF finger modules in a warm section was heating up or arcing, degrading the vacuum in that area and causing the slow local beam losses. The luminosity production was interrupted and, during the long Whitsun weekend, various teams intervened in the LHC tunnel to replace the RF finger module (with subsequent vacuum pumping). Already in the morning of Tuesday, 30 May, beams were injected and circulated to check the vacuum conditions. In the evening, a first fill with only 700 bunches per beam, followed by a second fill with 1200 bunches, were used for physics while also conditioning the area of the newly installed RF finger module. In the following days, the intensity ramped up to 2400 bunches and, in a second stage, the intensity per bunch was increased from 1.3x1011 to 1.6x1011 protons per bunch.
Until further notice and pending greater understanding of the cause of the RF finger module fault, the bunch intensity will be limited to 1.6x1011 protons per bunch. By now, the LHC is again filled with the default 2400 bunch filling scheme with 1.55x1011 protons per bunch, producing close to 1 fb-1 per day. As I write, the integrated luminosities for ATLAS and CMS are each 16 fb-1, which is about 5 fb-1 below the target value, but we’re catching up.
____
* “Slow local losses” happen when some beam particles get lost in specific parts of the ring when interacting with the gas molecules in the degraded vacuum. This process takes some time before the threshold to dump the beam is reached.
anschaef Wed, 06/07/2023 - 13:44 Byline Rende Steerenberg Publication Date Tue, 06/06/2023 - 13:27CERN marks World Environment Day with a new video
Monday 5 June marked the 50th anniversary of World Environment Day, one of the United Nations' vehicles for encouraging worldwide awareness and action for the environment. As a leading scientific organisation, CERN is committed to environmentally responsible research, with the support of its Member and Associate Member States and collaborating institutes, notably through the European Particle Physics Communications (EPPCN network). On this special day, CERN published a new video showcasing the diverse ways in which it acts to minimise its impact on the environment.
CERN will publish its third environment report later this year. In the meantime, you can find out more in its first and second reports on: https://hse.cern/environment-report.
anschaef Wed, 06/07/2023 - 11:37 Publication Date Wed, 06/07/2023 - 11:36Σελίδες
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