ATLAS

Searching for dark matter in all channels

Physicist at many Germany universities and unstitutes have contributed to the analyses in a recently published overview paper about the searches for Dark Matter at the ATLAS experiment. The paper has been accepted for publication by the Journal of High Energy Physics.

News article on ATLAS-FSP103
(Photo: ATLAS)

The question about the nature of Dark Matter stays unanswered. Thr ATLAS collaboration at CERN has summarised the searches for Dark Matter in a summary paper. With the data from proton-proton collisions at the LHC that was taken in 2015 and 2016, more stringent exclusion limits have been set on numerous representative processes. An extensive number of production mechanisms and final states have been covered.

BMBF supports Mainz projects in particle physics

Federal Ministry of Research provides 7 million euros for cooperative research work at CERN. ATLAS experiment and development of scintillator-based particle detectors as one of Mainz's main tasks in the coming years.

University Press Release
(Photo: ETAP/JGU)

Physicists from Johannes Gutenberg University Mainz (JGU) are involved in numerous projects of the international large-scale research institution CERN in Geneva. The Federal Ministry of Education and Research (BMBF) will continue to financially support this work in the coming years. For the three-year funding period until mid-2021, the BMBF provides nearly 7 million euros. "Projects at major research institutions are usually accompanied by a long-term commitment. “We therefore thank the Federal Ministry of Research for its continued support of these tasks with long-term, substantial funding,” says Prof. Dr. med. Georg Krausch, President of Johannes Gutenberg University Mainz. "The grants are also an award for our physicists, who make important contributions to the impressive research at CERN in many areas. We are also pleased that the achievements of the Mainz's physicists have been recently rewarded with the approval of the Cluster of Excellence PRISMA+," says the JGU President. The BMBF funds will be particularly used for Mainz's participation in cooperation projects such as the ATLAS experiment or the NA62 experiment.

One focus of the group Experimental Particle and Astroparticle Physics (ETAP) is the research on the Large Hadron Collider (LHC), the largest particle accelerator in the world, which has been in operation at CERN since 2008. "The Mainz group has taken a great deal of responsibility for the ATLAS experiment at the LHC," explains Prof. Dr. Volker Büscher from ETAP. Prof. Büscher is spokesperson of ATLAS Germany since July 2018, in which the 17 institutions working on the experiment are organised. ATLAS discovered the Higgs boson in 2012 together with another LHC experiment.

An important task of the ATLAS experts from Mainz is to analyze the data collected and recorded when the particles collide - more than 1 gigabyte per second. For this purpose, the Mainz supercomputer MOGON II, one of the fastest high-performance computers in the world, is available at the JGU. In addition, the physicists at Mainz University contribute to the upgrade of the ATLAS detector. They can rely on the infrastructure built up by the PRISMA Cluster of Excellence in Mainz, including the PRISMA Detector Laboratory. By granting the follow-up application for PRISMA+, this support will be secured in the future.

Looking to the future, the ETAP Group is developing novel particle detectors with a wide range of potential applications. In the BMBF joint project for research and development on scintillator-based detectors, Prof. Dr. Lucia Masetti, also a physicist of the University of Mainz, is the spokesperson for the joint project. "Scintillator-based particle detectors are ideal for a wide range of applications, the challenges of which we now address together as a community," says the scientist.

"Other activities we are particularly involved in, and funded by the BMBF, include the measurement of extremely rare kaon decays with the NA62 experiment, the search for axion-like particles, and machine learning," adds Büscher. The scientist notes that the LHC accelerator is in a long shutdown for the next two years since early December to carry out major upgrade work. "There is a lot to do for us during this time," says Prof. Büscher. "Then, with the LHC restarting with increased luminosity, we'll go deeper into exploring the smallest particles that make up our matter."

Members of the ETAP group receive ATLAS outstanding achievement award

Rosa Simoniello and Eduard Simioni from the ETAP group receive the ATLAS outstanding achievement award for outstanding contributions and dedication in successfully commissioning the Level-1 Topo trigger

ATLAS Press Release
(Photo: E. Ward/CERN)

Two members of the ETAP ATLAS group received the ATLAS outstanding achievement award for the work on the ATLAS Level-1 Topo trigger. They have been awarded the price together with Olga Igonkina, Murrough Landon and Imma Riu.

Higgs decay into bottom quarks discovered

It was a sensation in 2012: Scientists at CERN have discovered the Higgs Boson that have been postulated for decades. Now another prediction has been confirmed: The Higgs Boson decays into two bottom quarks.

original CERN press release
press release ATLAS Germany

The two independent research teams of the ATLAS and CMS experiments at LHC have succeeded in detecting Higgs decay into two bottom quarks.
Even before the concrete proof, theoreticians had long predicted the decay in bottom quarks. Although it is a common pattern of decay - it occurs in 58 percent of cases - the teams have only now succeeded to observe this decay mode. Since this reaction can not be observed directly, the researchers instead reconstructed the decay products of particle collisions in the LHC. For this they use high-precision detection devices the size of an apartment building. The challenge here: The pattern occurring resembles other, much more frequent decays, in which the Higgs Boson is not involved.
(Image ATLAS/CERN: HIGG-2018-04)

Higgs boson comes out on top

New results from the ATLAS and CMS experiments at the Large Hadron Collider (LHC) reveal how strongly the Higgs boson interacts with the heaviest known elementary particle, the top quark

original press release

Results presented today, at the LHCP conference in Bologna, describe the observation of this so-called "ttH production" process. Results from the CMS collaboration, with a significance exceeding five standard deviations for the first time, have just been published in the journal Physical Review Letters; including more data from the ongoing LHC-run, the ATLAS collaboration just submitted new results for publication, with a larger significance. The findings of the two experiments are consistent with one another and with the Standard Model. They tell scientists more about the properties of the Higgs boson and give clues for where to look for new physics.
(Image ATLAS Collaboration)

EU funding for four outstanding junior researchers at the JGU

Individual EU research fellowships in the Marie Skłodowska-Curie program support new projects in the fields of physics and paleogenomics

original press release

Four young scientists from abroad will receive new research projects at Johannes Gutenberg University Mainz (JGU) with the support of the EU. One of them, Dr. Peter Berta is a member of our group and will conduct research in the field of Higgs boson physics. The funding is provided by individual EU research grants in the Marie Skłodowska-Curie program - a high honor for the beneficiaries. The EU supports the outstanding young researchers for a total of € 650,000 over a period of 24 months.

With the discovery of the Higgs boson in the summer of 2012 at the CERN research center, the question of the mechanism that gives elementary particles a mass has been clarified. However, many new questions about the properties of the Higgs boson itself have surfaced. Dr. Peter Berta is working in the group of Prof. Dr. Lucia Masetti on the interaction between the Higgs boson and the top quark, which can be measured in proton-proton collisions at the Large Hadron Collider at CERN, with the ATLAS experiment. If the measurement deviates from the Standard Model of particle physics, it would indicate new phenomena that could answer many unanswered questions about the fundamental interactions. Peter Berta, born in Slovakia, completed his doctorate at the Charles-University in the Czech Republic and has been working with the ATLAS experiment since 2012. He has been working as a postdoctoral fellow at JGU since March 2017.
(Photo: Cornelia Kirch)

The 2018 data-taking run at the LHC has begun

On Saturday, 28 April 2018, the operators of the Large Hadron Collider (LHC) successfully injected 1200 bunches of protons into the machine and collided them. This formally marks the beginning of the LHC’s 2018 physics season. The start of the physics run comes a few days ahead of schedule, continuing the LHC’s impressive re-awakening since the end of its annual winter hibernation just over a month ago.

original press release
(Photo:ATLAS/CERN)

First LHC test collisions of 2018

Proton slamming has resumed at the Large Hadron Collider (LHC). Almost a fortnight after the collider began circulating proton beams for the first time in 2018, the machine’s operations team has today steered beams into collision. While these are only test collisions, they are an essential step along the way to serious data taking, which is expected to kick off in early May.

original press release
(Image:CERN)

Beams are back in the LHC

On Friday 30 March, at 12:17 pm, protons circulated in the 27-km LHC ring for the first time in 2018. The Large Hadron Collider entered its seventh year of data taking and its fourth year at 13 TeV collision energy.

original press release
(Image:CERN)