DESY

The particle accelerator DESY (acronym for Deutsches Elektronen-Synchrotron or German Electron Synchrotron) was the first particle accelerator of the DESY research centre in Hamburg and the one that gave the research centre its name. The DESY synchrotron was used for research in particle physics from 1964 to 1978 and served as a pre-accelerator for other accelerator facilities at DESY.Construction of the synchrotron started in 1960. With a circumference of 300 m, it was the world's largest facility of its kind in the world and accelerated electrons to 7.4 GeV. The first electrons circulated in the acceleration on 25 February 1964, and research activities into elementary particles at the DESY synchrotron started in May 1964. In the experiments carried out at DESY, the electron beams were directed at fixed targets.

The Positron-Electron Tandem Ring Accelerator (PETRA) is one of the particle accelerators at DESY in Hamburg, Germany. From 1978 to 1986 it was used to study electron–positron collisions. It was here that the TASSO collaboration found the first direct evidence for gluons in three jet events. The modification called PETRA-II is a source of high-energy synchrotron radiation and also a pre-accelerator for the HERA. Started in 2007, an upgrade has been converting it to PETRA-III, which is a high intensity source for synchrotron radiation.

HERA (German: Hadron-Elektron-Ringanlage, English: Hadron-Electron Ring Accelerator) was a particle accelerator at DESY in Hamburg. It began operating in 1992. At HERA, electrons or positrons were collided with protons at a center of mass energy of 318 GeV. It was the only lepton-proton collider in the world while operating. Also, it was on the energy frontier in certain regions of the kinematic range. HERA was closed down on 30 June 2007.The HERA tunnel is located under the DESY site and the nearby Volkspark around 15 to 30 m underground and has a circumference of 6.3 km. Leptons and protons were stored in two independent storage rings on top of each other inside this tunnel. There are four interaction regions, which were used by the experiments H1, ZEUS, HERMES and HERA-B. All these experiments were particle detectors. Leptons (electrons or positrons) were pre-accelerated to 450 MeV in the linear accelerator LINAC-II. From there they were injected into the storage ring DESY-II and accelerated further to 7.5 GeV before their transfer into PETRA, where they were accelerated to 14 GeV. Finally they were injected into their storage ring in the HERA tunnel and reached a final energy of 27.5 GeV. This storage ring was equipped with warm (non-superconducting) magnets keeping the leptons on their circular track by a magnetic field of 0.17 Tesla. Protons were obtained from originally negatively charged hydrogen ions and pre-accelerated to 50 MeV in a linear accelerator. They were then injected into the proton synchrotron DESY-III and accelerated further to 7 GeV. Then they were transferred to PETRA where they were accelerated to 40 GeV. Finally, they were injected into their storage ring in the HERA tunnel and reached their final energy of 920 GeV. The proton storage ring used superconducting magnets to keep the protons on track. The lepton beam in HERA became naturally transversely polarised through the Sokolov-Ternov effect. The characteristic build-up time expected for the HERA accelerator was approximately 40 minutes. Spin rotators on either side of the experiments changed the transverse polarisation of the beam into longitudinal polarisation. The positron beam polarisation was measured using two independent polarimeters, the transverse polarimeter (TPOL) and the longitudinal polarimeter (LPOL). Both devices exploit the spin-dependent cross section for Compton scattering of circularly polarised photons off positrons to measure the beam polarisation. The transverse polarimeter was upgraded in 2001 to provide a fast measurement for every positron bunch, and position-sensitive silicon strip and scintillating-fibre detectors were added to investigate systematic effects. On 30 June 2007 at 11:23 pm, HERA was shut down, and dismantling of the four experiments started. HERA's main pre-accelerator PETRA was converted into a synchrotron radiation source, operating under the name PETRA-III since August 2010.

Netzwelt (own writing: netzwelt) is a technology-related news website run by Netzwelt GmbH. The two founders, Dirk and Sascha Hottes, founded Netzwelt in early 1999 in Darmstadt. The site, which bills itself as "Guter Rat auf einen Klick" (Good advice at a click), features consumer electronics and software, as well as user-generated content in a popular forum. With up to 4,8 million visitors and 18 million page impressions, Netzwelt is one of the top five IT websites in Germany, Austria and Switzerland.

Bahrenfeld is a western quarter of the city of Hamburg in Germany, it is subject to the district/borough Bezirk Altona and was an independent settlement until 1890. It is home to DESY and the Barclaycard Arena. In 2020 the population was 29,652.

Groß Flottbek (German pronunciation ), (Great Flottbek) is a quarter of Hamburg, Germany, in the borough of Altona. It is located in the center of the borough north of the Othmarschen quarter. Near Groß Flottbek, the neighbourhood of Klein Flottbek, which is not an official quarter, can be found. Around 11.000 people live in Groß Flottbek on 2.4 sq km.

Trabrennbahn Bahrenfeld, located in the Bahrenfeld quarter of Hamburg, Germany, is used for harness racing. It was built in 1867 and renovated in 2011.The track has a capacity of 30,000. Maximum capacity for concerts is 90,000.

Altona Main Cemetery (German: Hauptfriedhof or Friedhof Altona) is located at Stadiongasse 5, Bahrenfeld, Altona, in north-western Hamburg, Germany and, with an area of 63 hectares, is the fourth largest burial ground in the city and surrounding area. It has been a protected site since the revision of the Hamburg Monument Protection Law (Hamburger Denkmalschutzgesetz) in 2013.

H1 was a particle detector that operated at HERA (Hadron Elektron Ring Anlage) in DESY, Hamburg. The first studies for the H1 experiment have proposed in 1981 and the H1 detector began operating together with HERA in 1992 and took data until 2007. The detector consisted of several different detector components and was about 12 x 15 x 10 meters big and weighs 2800 tons. It was accompanied by further detectors in both directions of the HERA accelerator and by an electronics trailer three stories high. The main physics goals of the H1 experiment were the investigation of the internal structure of the proton through measurements of deep inelastic scattering, the measurements of further cross sections to study fundamental interactions between particles in order to test the Standard Model of particle physics, as well as searching for particles beyond the Standard Model. The name H1 is used for both, the detector itself and the collaboration of physicists and technicians who operated the experiment.

ZEUS was a particle detector that operated on the HERA (Hadron Elektron Ring Anlage) particle accelerator at DESY, Hamburg. It began running together with HERA in 1992 and was functional until HERA was decommissioned in June 2007. The scientific collaboration behind ZEUS consisted of about 400 physicists from 56 institutes in 17 countries.The ZEUS detector comprised many components, including a depleted uranium plastic-scintillator calorimeter, a central tracking detector (which is a wire chamber), a silicon microvertex detector and muon chambers. In addition, a solenoid provides a 1.43 T magnetic field. The ZEUS experiment studied the internal structure of the proton through measurements of deep inelastic scattering by colliding leptons (electrons or positrons) with proton in the interaction point of ZEUS. These measurements were also used to test and study the Standard Model of particle physics, as well as searching for particles beyond the Standard Model.

Lurup (listen ) is a quarter in the Altona borough of the Free and Hanseatic city of Hamburg in northern Germany. It was formerly an independent village. In 2020 the population was 36,521.

Othmarschen railway station is on the Altona-Blankenese line and served by the city trains, located in Hamburg, Germany. The station was opened in 1897. The rapid transit trains of the line S1 and the line S11 of the Hamburg S-Bahn calls the station in the quarter Othmarschen of the Altona borough. Right along the railway tracks is the border to the quarter Groß Flottbek.