Venerque – La Trinité

Lien Atlas (MCC) :http://atlas.patrimoines.culture.fr/atlas/trunk/index.php?ap_theme=DOM_2.01.02&ap_bbox=1.427;43.415;1.499;43.458 L’opération de diagnostic archéologique réalisée à Venerque s’inscrit dans le cadre d’un prochain aménagement d’un lotissement sur plusieurs terrains situés au lieu-dit la Trinité. La prescription de ce diagnostic a été motivée par la proximité immédiate de la nécropole de Loupsaout-La Trinité, découverte dans les années 1950 lors d’un défoncement agricole à quelq..

Venerque – La Trinité

Lien Atlas (MCC) :http://atlas.patrimoines.culture.fr/atlas/trunk/index.php?ap_theme=DOM_2.01.02&ap_bbox=1.427;43.415;1.499;43.458 L’opération de diagnostic archéologique réalisée à Venerque s’inscrit dans le cadre d’un prochain aménagement d’un lotissement sur plusieurs terrains situés au lieu-dit la Trinité. La prescription de ce diagnostic a été motivée par la proximité immédiate de la nécropole de Loupsaout-La Trinité, découverte dans les années 1950 lors d’un défoncement agricole à quelq..

Fast Neutron Detectors Based On Micromegas Technology

After a short description of the Micromegas principle, a new concept of neutron detectors based on this technique is presented. The report is illustrated by an overall picture of the possible use of these detectors in different domain such as: nuclear physics, inertial fusion and industrial application. A particular description will be devoted to the compact detector named "PiccoloMicromegas". This detector, able to measure neutron flux in a broad range of energy of neutron (from thermal to several MeV), is developed for the measurements of neutrons flux in-core of the future generations of the nuclear reactors (fast and possibly Accelerator Driven System (ADS))

Heat deposition by transient beam passage in spoilers

Future electron-positron linear colliders must produce bunches of tiny emittance grouped in short bunch trains in order to provide adequately large luminosities. A collimation system must be installed between the end of the main linac and the optical elements of the final focus to protect the detectors from errant beams. With ordinary values of the betatron functions, the transverse beam size is of a few microns. With such sizes, the local deposition of heat of even a single bunch train is so high that no material can survive such an event.The problem is solved by increasing the beam sizes at the location of the collimators. But the use of large betatron functions is costly and can induce strong optical errors. It is therefore important to compute precisely safe beam sizes which allow the survival of the collimators, in order to limit their increase to the minimum needed. The deposition of heat occurs both by ionisation along the path of the particles which traverse the material and by ohmic image current heating at the surface of the collimator, for that fraction of the beam which flies outside the collimator.With small bunches, heat diffusion is substantial even with short bunch trains and helps to reduce the excursion of temperature. The rise of temperature is computed by solving analytically the time-dependent heat equation in two spatial dimensions near an interface with vacuum. Numerical results are given for the CLIC study

A new low intensity beam profiler for SPIRAL2

WEPF14International audienceIn the framework of SPIRAL 2 ion beams, several beam profile monitors are presently being developed at GANIL. One of them is a low-intensity beam-profile monitor that works as a secondary electron detector. This Emission-Foil Monitor (EFM) will be used in the radioactive beam lines of SPIRAL2 and in the experimental rooms of this new facility. The ions produce secondary electrons when they are stopped in an aluminium emissive foil. The electrons are then accelerated using an electric field and guided using a magnetic field to a double-stage microchannel plate (MCP). A 2D pixellated pad plane placed below the MCP is used to collect the signals. The magnetic field created by permanent magnets in a closed magnetic circuit configuration permits the beam-profile reconstruction to be achieved with a good resolution. The EFM can visualize beam-profile intensities between only a few pps to as much as 109 pps and with energies as low as several keV. This profiler has been under development since 2009 and is currently manufactured. Recent results of this monitor are presented in this article

MAD Version 9

The program MAD is widely used for accelerator design and beam dynamics studies. For many years, its input language has been the nearest thing to a world-wide standard for describing accelerator structures. The new Version 9 is a complete rewrite using a systematic object-oriented methodology based on the CLASSIC classes [2] for accelerator physics. It provides many improvements over the previous MAD Version 8. These include: (i) support for multiple beam-lines simultaneously, facilitating, for example, matching constraints that couple the two rings of a two-ring collider, (ii) much improved Lie-algebraic map calculations, (iii) a uniform method and format for exchanging many kinds of structured data with other programs, (iv) an improved and more consistent input language. In addition, we report on a parallel 3D Poisson field solver for space charge calculations in high intensity particle beams. Applied to the PSI injector cyclotron, this shows the general nature of MAD Version 9 as a state-of- the-art problem-solving environment. We describe the current status of the program and how to get it, outline future plans and illustrate some of the new features

Micromegas at low pressure for beam tracking

New facilities like FAIR at GSI or SPIRAL2 at GANIL, will provide radioactive ion beams at low energies (less than 10 MeV/n). Such beams have generally a large emittance, which requires the use of beam tracking detectors to reconstruct the exact trajectories of the nuclei. To avoid the angular and energy straggling that classical beam tracking detectors would generate in the beam due to their thickness, we propose the use of SED (Secondary Electron Detectors). It consists of a low pressure gaseous detector placed outside the beam coupled to an emissive foil in the beam. Since 2008, different low pressure gaseous detectors (wire chambers and micromegas) have been constructed and tested. The performances achievable at low pressure are similar to or even better than the ones at atmospheric pressure. The fast charge collection leads to excellent timing properties as well as high counting rate capabilities. Several micromegas at low pressure were tested in the laboratory demonstrating a good time resolution, 13030 ps, which is compatible with the results obtained with wire chambers.Gobierno de España FPA2009-0884

Un four de potier du dernier quart du IIIe s. av. n. è. au Mas de Fourques (Lunel, Hérault)

Une fouille préventive a permis d’exhumer un four de potier daté de la fin du IIIe siècle avant notre ère à proximité de l’oppidum d’Ambrussum. Il est situé en piedmont d’une colline, à deux kilomètres à l’ouest du Vidourle. Ce four de grande dimension présente une structure circulaire à double entrée avec un muret séparant en deux la totalité de la chambre de chauffe et de l’alandier. L’aire de chauffe a également été intégralement dégagée. Lors de la fouille ont été mises en évidence la phase de fonctionnement du four et son abandon marqué par le comblement de la structure avec des matériaux provenant du four (terre rubéfiée, blocs, briques, torchis) et de nombreux fragments de vases, en très grande majorité de la céramique non tournée. Aucun rebus de cuisson n’a été retrouvé, la production de ce four n’a pas donc pu être établie avec certitude. Les différentes opérations préventives conduites dans le secteur n’ont révélé aucune autre structure contemporaine de ce four.A preventive excavation led to the discovery of a potter’s kiln dating to the end of the 3rd century BC near the oppidum of Ambrussum. It is situated at the base of a hill, two kilometres west of the Vidourle river. This kiln of large dimensions presents a circular structure with a double entrance and a low wall separating in two the totality of the heating chamber and fire chamber. The heating area was also cleared entirely. During the excavation the functioning phase of the kiln was revealed and so was its abandonment, which is shown by the filling of the structure with materials resulting from the kiln (burnt earth, blocks, bricks, cobs) and numerous fragments of vases, in very great majority handmade ceramic. No rebus of pottery firing was found, the production of this kiln was thus impossible to establish with certainty. The various preventive operations led in the sector revealed no other contemporary structure of this kiln

Un four de potier du dernier quart du IIIe s. av. n. è. au Mas de Fourques (Lunel, Hérault)

Une fouille préventive a permis d’exhumer un four de potier daté de la fin du IIIe siècle avant notre ère à proximité de l’oppidum d’Ambrussum. Il est situé en piedmont d’une colline, à deux kilomètres à l’ouest du Vidourle. Ce four de grande dimension présente une structure circulaire à double entrée avec un muret séparant en deux la totalité de la chambre de chauffe et de l’alandier. L’aire de chauffe a également été intégralement dégagée. Lors de la fouille ont été mises en évidence la phase de fonctionnement du four et son abandon marqué par le comblement de la structure avec des matériaux provenant du four (terre rubéfiée, blocs, briques, torchis) et de nombreux fragments de vases, en très grande majorité de la céramique non tournée. Aucun rebus de cuisson n’a été retrouvé, la production de ce four n’a pas donc pu être établie avec certitude. Les différentes opérations préventives conduites dans le secteur n’ont révélé aucune autre structure contemporaine de ce four.A preventive excavation led to the discovery of a potter’s kiln dating to the end of the 3rd century BC near the oppidum of Ambrussum. It is situated at the base of a hill, two kilometres west of the Vidourle river. This kiln of large dimensions presents a circular structure with a double entrance and a low wall separating in two the totality of the heating chamber and fire chamber. The heating area was also cleared entirely. During the excavation the functioning phase of the kiln was revealed and so was its abandonment, which is shown by the filling of the structure with materials resulting from the kiln (burnt earth, blocks, bricks, cobs) and numerous fragments of vases, in very great majority handmade ceramic. No rebus of pottery firing was found, the production of this kiln was thus impossible to establish with certainty. The various preventive operations led in the sector revealed no other contemporary structure of this kiln