A European Advanced Technology Programme for ADS Accelerator Development

Consecutive to the work of the European Technical Working Group on ADS, the Preliminary Design Study of an Experimental ADS was launched in 2001 as a 5th Framework Program EC project. A special working package was dedicated to the accelerator design, and in particular taking into account that the issue of “beam trips” could be a potential “show-stopper” for ADS technology in general. A reference solution, based on a linear superconducting accelerator with its associated doubly achromatic beam line has been worked out up to some detail. For very high reliability, the proposed design is intrinsically fault tolerant, relying especially on highly modular “de-rated” components associated to a fast digital feedback system. A programme for the remaining R&D, focused on experimental reliability demonstration of prototypical components, has been elaborated. This R&D will be performed in the 6th Framework Program EC project EUROTRANS, which presently is just starting

A reference accelerator scheme for ADS applications

Accelerator Driven Systems (ADS) for transmutation of nuclear waste typically require 350 MeV–1 GeV accelerators delivering proton fluxes of 5–10 mA for demonstrators, and 20–50 mA for large industrial systems. Thus, such machines belong to the category of the so-called HPPA (High-Power Proton Accelerators), with multi-megawatt beam power. HPPA are presently developed and constructed at great pace for their broad utility in fundamental or applied science. Compared to other HPPA, many features and requirements are similar for the ADS driver. However, there is a need for exceptional reliability: because of the induced thermal stress to the sub-critical core, the number of unwanted “beam-trips” should not exceed a few per year, a requirement that is several orders of magnitude above usual performance. Consecutive to the work of the European Technical Working Group (ETWG) on ADS, the Preliminary Design Study of an Experimental ADS (PDS-XADS) was launched in 2001 as a 5th Framework Program EC project.1 A special Working Package (WP3) was dedicated to the accelerator design, taking especially into account that the issue of “beam-trips” could be a potential “show-stopper” for ADS technology in general. A reference solution, based on a linear superconducting accelerator with its associated doubly achromatic beam line, has been worked out to some detail. For high reliability, the proposed design is intrinsically fault tolerant, relying on highly modular “de-rated” components associated to a fast digital feedback system. The proposed solution also appears to be robust concerning operational aspects like maintenance and radioprotection. A roadmap for construction as well as the required consolidated budget was elaborated. A program for the remaining R&D, focused on experimental reliability demonstration of prototypical components has been elaborated. This R&D will be performed in the 6th Framework Program EC project EUROTRANS,2 which presently is just starting

Neutron Irradiation Tests of Calibrated Cryogenic Sensors at Low Temperatures

This paper presents the advancement of a program being carried out in view of selecting the cryogenic temperature sensors to be used in the LHC accelerator. About 10,000 sensors will be installed around the 26.6 km LHC ring, and most of them will be exposed to high radiation doses during the accelerator lifetime. The following thermometric sensors : carbon resistors, thin films, and platinum resistors, have been exposed to high neutron fluences (>10$^15$ n/cm$^2$) at the ISN (Grenoble, France) Cryogenic Irradiation Test Facility. A cryostat is placed in a shielded irradiation vault where a 20 MeV deuteron beam hits a Be target, resulting in a well collimated and intense neutron beam. The cryostat, the on-line acquisition system, the temperature references and the main characteristics of the irradiation facility are described. The main interest of this set-up is its ability to monitor online the evolution of the sensors by comparing its readout with temperature references that are in principle insensitive to the neutron radiation (i.e. Argon gas bulbs when working at about 84 K, and below 4.5 K, either helium gas bulbs or the saturation pressure of the superfluid helium bath). The resistance shifts of the different sensors at liquid helium temperatures are presented

Neutron Irradiation Tests in Superfluid Helium of LHC Cryogenic Thermometers

For control and monitoring purposes, about 10,000 individually calibrated cryogenic temperature sensors will be installed along the 26.7 km LHC. In order to reduce maintenance constraints these sensor s should be as immune as possible to the high neutron fluence environment. For selecting the sensor to be used, a radiation hardness evaluation program at cryogenic conditions is being performed in an irradiation vault of the ISN SARA Cyclotron (Grenoble, France). The set-up is capable of simulating the whole life of a LHC thermometer: same total neutron dose (1015 n.cm-2), irradiation at low tempe rature (1.8 K) and thermal cycles. Bath temperature and sensor resistance are monitored on-line. This paper presents the latest results of this program

New acyclic diaminocarbenes cycloplatinated(II) complexes: synthesis, photophysical properties and cytotoxic activity

Among all phosphorescent molecules, cyclometalated platinum(II) complexes have receivedconsiderable attention because of their photophysical properties and potential applications asdopants in OLEDs, LECs, photocatalysts or bioimaging. Another research of relevant interest istheir employment as anticancer drugs with a broader spectrum of action against differenttumours and fewer side effects than the well-known cisplatin. For that reason, the choice of thecyclometalated group and ancillary ligands play an important role not only in emissive behaviorbut also on the biological activity.1N-acyclic diaminocarbenes (ADCs) show several appealing characteristics; they display strongelectron-donating ability with structural flexibility and can be easily prepared. However, thereare only a few examples of ADC-platinum complexes used as perspective metal-based drugs inthe literature.2In this contribution, we describe a series of new luminescent ADC cycloplatinated(II) compoundsfeaturing 2-(2,4-difluorophenyl)pyridine (3) and 2-phenylquinoline (4) cyclometalated groups[Pt(C^N)Cl{C(NHXyl)(NHR)}] (R = Pr a, Benzyl b) obtained by nucleophilic addition of primarypropyl and benzyl amines, to the isocyanide ligand of the corresponding precursors[Pt(C^N)Cl(CNXyl)] (1, 2) recently reported by our group.3 Their optical properties haveexamined and interpreted with the aid of DFT/TD-DFT calculations and, finally, all newcompounds have been screened for their cytotoxic activity against various cancer cell lines