Press Releases and News

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)

IceCube researchers trace the origin of a neutrino from the depths of the cosmos

Elementary particles originate from three billion light-years distant galaxy / black hole as particle accelerator

original press release

Multimessenger astrophysics has been crowned with success: a research team has for the first time located a cosmic source of high-energy neutrinos. The trigger for the search was a single high-energy neutrino, which had been detected on 22 September 2017 in the ice of Antarctica by the neutrino telescope IceCube. Earth and space telescopes subsequently determined the origin of this elementary particle. It lies in a galaxy three billion light-years distant in the constellation Orion, in which a gigantic black hole naturally accelerates particles. Scientists from 16 astronomical observatories participated in the campaign worldwide. Among the researchers are also Prof. Dr. Sebastian Böser and Prof. Dr. Lutz Köpke from the Institute of Physics of Johannes Gutenberg University Mainz (JGU), which belongs since 1999 to the IceCube consortium. The results of this joint search were recently published in the journal Science.
(Image Martin Wolf, IceCube/NSF, 2017)

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)

Sensitivity record in the search for dark matter

XENON1T sets new limits for "WIMPs" - Mainz scientists are among the founding members of the XENON program for the search for dark matter

original tweet
University press release
paper link

On May 28th, Prof. Elena Aprile from Columbia University, spokeswoman for the XENON collaboration, and Prof. Manfred Lindner from the Max Planck Institute for Nuclear Physics in lectures at LNGS and CERN present the latest results of XENON1T, the world's largest and most sensitive detector for the direct search for dark matter in the form of WIMPs (weakly interacting massive particles). The extensive data set of 1 ton × year agrees with the expectation for the background, thus setting the strongest limit for spin-independent interaction of WIMPs with normal matter for a WIMP mass of more than 6 GeV / c². These results show that WIMPs - if they are indeed the dark matter particle - produce such a rare signal that even the largest and most sensitive detector built so far can not detect it.

XENON1T continues to collect data until the larger version of the detector currently being prepared is ready for use, for which most components are already designed. With three times more xenon in the time-projection chamber and ten times lower background rate, XENONnT will launch a new phase of dark matter particle search beginning in 2019.

Prof. Dr. Uwe Oberlack from the Johannes Gutenberg University Mainz is one of the founding members of the XENON program on the search for dark matter. The Mainz working group is involved in the XENON experiments in both data analysis and simulations as well as detector technology. Mainz astroparticle physicists are responsible for the muon detector and are involved in the ReStoX xenon storage system and the inner detector. In order to make another leap in sensitivity in the next step with the XENONnT experiment, the group is working on the development of a subdetector for the detection of neutrons. The research is also part of the Cluster of Excellence PRISMA, which is funded by the "Exzellenzinitiative des Bundes und der Länder".
(Plot XENON 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)