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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.

The Deutsches Elektronen-Synchrotron (English German Electron Synchrotron) commonly referred to by the abbreviation DESY, is a national research center in Germany that operates particle accelerators used to investigate the structure of matter. It conducts a broad spectrum of inter-disciplinary scientific research in three main areas: particle and high energy physics; photon science; and the development, construction and operation of particle accelerators. Its name refers to its first project, an electron synchrotron. DESY is publicly financed by the Federal Republic of Germany, the States of Germany, and the German Research Foundation (DFG). DESY is a member of the Helmholtz Association and operates at sites in Hamburg and Zeuthen.

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.

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.

The Gymnasium Christianeum is a famous former Latin school (German: Lateinschule) in Hamburg, northern Germany. Founded in 1738 by King Christian VI of Denmark, it is now housed in a building planned by Danish designer Arne Jacobsen.

The Loki-Schmidt-Garten, also known as Botanischer Garten Hamburg, or, more formally, as Botanischer Garten der Universität Hamburg or Biozentrum Klein Flottbek und Botanischer Garten, is a botanical garden maintained by the University of Hamburg. It has a size of around 25 hectares and is located at Ohnhorststrasse 18, Hamburg, Germany, beside the Klein Flottbek station in the Osdorf quarter, and open daily without charge. It was renamed in 2012 after Loki Schmidt, the wife of the former German chancellor Helmut Schmidt. Though it was renamed, the old name coexists with the new one. Nearby Klein Flottbek station still has the second name "Botanischer Garten".

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.

The Lise-Meitner-Gymnasium (LMG) is a high school in Osdorf, Hamburg. It bore the name Gymnasium Osdorf until 1 January 2007, when it officially adopted the name of the Austrian-Swedish nuclear physicist Lise Meitner.

Klein Flottbek (Botanischer Garten) railway station is on the Altona-Blankenese line and serviced by the Hamburg city trains. Rapid transit trains of lines S1 and S11 of the Hamburg S-Bahn call at the station in the Klein Flottbek subdistrict in the Nienstedten quarter of Altona borough in Hamburg, Germany. The track forms the border of the Osdorf quarter. The station is near the main entrance of the Botanischer Garten Hamburg, in Osdorf.

The Ernst Barlach House – Hermann F. Reemtsma Foundation (German: Ernst-Barlach-Haus – Stiftung Hermann F. Reemtsma) is an art museum in Hamburg, Germany, devoted to the Expressionist artist Ernst Barlach. The museum was founded by the industrialist Hermann F. Reemtsma, and is located in the Jenisch park in Othmarschen in the west of the city. The squat, functionalist museum building was begun in 1961 by the Hamburg architect Werner Kallmorgen, finished in 1962 after Reemtsma's death, and extended in 1996 with new rooms for temporary exhibitions. There is also a library containing literature on Barlach and his era. Reemtsma had begun to build a collection of Barlach's works in the mid-1930s, after first meeting the multi-talented draughtsman, graphic artist, sculptor and dramatist. Towards the end of the decade he sought to defend this collection as securely as possible against Fascist vandalism, after Barlach's cenotaphs in Kiel (Holy Ghost Church) and Güstrow (cathedral) were destroyed, 381 of his works were seized, and Barlach was classified as a "degenerate" artist and banned from working or being exhibited. In the 1950s Reemtsma established the art foundation that bears his name, in order to preserve Barlach's works and make them accessible to the public. Shortly before his death in 1961 he commissioned the construction of the museum, which now states that its inventory has more than doubled since then and includes "around 140 works in wood, bronze, ceramics, porcelain, terracotta and plaster, more than 400 drawings from all his creative periods, almost all his printed graphics, as well as important autographs, rare portfolios, first editions and records".

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.

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.