LLRF Control and Synchronization System of the ARES Facility

The linear accelerator ARES (Accelerator Research Experiment at SINBAD) is a new research facility at DESY. Electron bunches with a maximum repetition rate of 50 Hz are accelerated up to 155 MeV. The facility aims for ultra-stable sub-femtosecond arrival-times and high peak-currents at the experiment, placing high demands on the reference distribution and field regulation of the S-band RF structures. In this paper, we report on the current status of the RF reference generation, facility-wide distribution, and the LLRF systems of the RF structures

Requirements and Status of PETRA IV Fast Orbit Feedback System

PETRA IV is the upcoming low-emittance, 6 GeV, fourthgenerationlight source at DESY Hamburg. It is based upona six-bend achromat lattice with additional beamlines ascompared to PETRA III. A stringent stability of the electronbeam orbit in the ring will be required to achieve adiffraction-limited photon beam quality. In this regard, therequirements and the proposed topology of the global orbitfeedback system are discussed for expected perturbations.An initial analysis based upon system requirements, designand modeling of the subsystems of the orbit feedback systemis also presented

Biallelic loss of CDKN2A is associated with poor response to treatment in pediatric acute lymphoblastic leukemia

The inactivation of tumor suppressor genes located within 9p21 locus (CDKN2A, CDKN2B) occurs in up to 30% of children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL), but its independent prognostic significance remains controversial. In order to investigate the prognostic impact of deletions and promoter methylation within 9p21, 641 children with newly diagnosed BCP-ALL using methylation specific multiplex ligation-dependent probe amplification (MS-MLPA) were investigated. A total of 169 (26.4%) microdeletions in 9p21 were detected, of which 71 were homozygous. Patients with CDKN2A homozygous deletions were older at diagnosis (p < .001), more frequently steroid resistant (p = .049), had higher WBC count (p < .001), higher MRD at Day 15 (p = .013) and lower relapse-free survival [p = .028, hazard ratio: 2.28 (95% confidence interval: 1.09-4.76)] than patients without these alterations. CDKN2A homozygous deletions coexisted with IKZF1 and PAX5 deletions (p < .001). In conclusion, CDKN2A homozygous deletions, but not promoter methylation, are associated with poor response to treatment and increased relapse risk of pediatric BCP-ALL.status: publishe

Installation and First Commissioning of the LLRF System for the European XFEL

The installation of the European X-ray Free Electron Laser (XFEL) is finished, leaving place for its commissioning phase. This contribution summarizes the low-level radiofrequency (LLRF) commissioning with a special emphasis on the development of automation tools to support the commissioning of such a large scale accelerator. First results ofthe LLRF commissioning in the main linac are also given