Formation of hydrogen ion beams with high intensity and low transverse emittance is one of the key challenges in accelerator technology. Present work is devoted to experimental investigation of proton beam production from dense plasma (Ne > 10 13 cm −3 ) of an ECR discharge sustained by 37.5 GHz, 100 kW gyrotron radiation at SMIS 37 facility at IAP RAS. The anticipated advantages of the SMIS 37 gasdynamic ion source over the current state-of-the-art proton source technology based on 2.45 GHz hydrogen discharges are described. Experimental result obtained with different extraction configurations i.e. single-and multi-aperture systems are presented. It was demonstrated that ultra bright proton beam with approximately 4.5 mA current and 0.03 π•mm•mrad normalized emittance can be produced with the single-aperture (1 mm in diameter) extraction, the corresponding brightness being 5 A/(π•mm•mrad) 2 . For production of high current beams a multi-aperture extractor was used resulting to a record of 200 mA / 1.1 π•mm•mrad normalized emittance proton beam. The species fraction i.e. the ratio of H + to H + 2 current was recorded to be > 90 % for all extraction systems. A possibility of further enhancement of the beam parameters by improvements of the extraction system and its power supply is discussed.
phyry copper ore-magmatic system have remained debatable.Under the current economic conditions of northeastern Russia, most of the known porphyry Cu-Mo deposits and occurrences are not promising for economic development. However, the metallogenic belts and zones where these deposits are located are extremely important in forecasting of potentially economic highgrade epithermal gold-silver deposits.At different times, we have studied the metallogenic belts and ore districts considered below. The most recent results of thermobarogeochemical studies were obtained only in 2005. In preparing this paper, we pursued the following goals: (i) to consider the current state of the problem and to summarize the previously obtained results, (ii) to outline the geodynamic settings favorable for formation of porphyry-type Au-bearing Cu-Mo deposits in the Northeast of Russia and the main trends in their spatial distribution, (iii) to review the geology of typical deposits and the ore composition therein, (iv) to study ore formation conditions in a comparative aspect, and (v) to clarify the relationships between epithermal Au-Ag and porphyry Cu-Mo ores in the common ore-forming system. GENERAL OUTLINE OF PORPHYRY-TYPE DEPOSITSPorphyry-type deposits are the main worldwide source of Cu and Mo; Au, Ag, and platinum group and some other rare metals are recovered from this ore as by-products. Porphyry deposits are accompanied by Abstract -By analogy with other metallogenic belts of the Circum-Pacific ring, the metallogenic belts in the Northeast of Russia are promising for discovery of large and superlarge porphyry-type Au-Cu-Mo deposits. The spatial distribution of these deposits is controlled by intrusive domes in Middle Paleozoic, Late JurassicEarly Cretaceous, and Late Cretaceous volcanic belts. New data on formation conditions and sources of ore matter are presented in this paper with respect to the deposits of the Baim and Koni-P'yagina ore districts of the Oloi and Uda-Murgal metallogenic belts. Some aspects of a geological and genetic model of the porphyry copper ore-magmatic system are discussed.
The Okhotsk-Chukotka volcanic belt (OChVB) formed over 25 Ma from the middle Albian to the Cenomanian at the boundary of the continental Verkhoyansk-Chukotka and the Koryak-Kamchatka collages of terranes as a special tectonic unit of the Earth's crust composed of subaerial volcanic rocks extending for 3000 km. In regard to the oceanic margin, the inner, outer, and flank zones of the OChVB have been recognized. The complex structure of terranes in the basement and the OChVB itself resulted in the formation of diverse epithermal deposits. Porphyry copper-molybdenum deposits are concentrated in the inner zone. The outer zone is characterized by gold-silver ore mineralization and a variety of tin deposits. Silver-base-metal deposits (Dukat, Lunny, Arylakh, etc.) are confined to the rift-related volcanic trough that complicates the OChVB between the Yana-Kolyma and Omolon terranes.
Abstract-Mineralogical-geochemical studies have shown that gold from the Plavica high sulfidation epith ermal deposit (Republic of Macedonia) contains an admixture of Fe and Cu, that the morphology of gold indicates the proximity of the primary source, and that the chemical composition of gold is independent of its morphology. The composition of gold and its morphology are the direct searching criteria, indicating the genetic type of mineralization. Pan sampling and the subsequent study of the typomorphism of gold may serve as an effective method for searching for epithermal high sulfidation deposits. Pan sampling allows us to distin guish and study in detail the chemical composition and morphology of native gold from deposits of this type.
The Shkol'noe deposit is localized in a small granitoid stock, the root portion of which is traced using geophysical data to a depth of 5-8 km. The high grade gold ore (33 gpt Au) is enriched in silver and principally differs in ore composition from the previously studied mesothermal gold-quartz and epithermal gold-silver deposits in the Russian Northeast. The main reserves of the Shkol'noe deposit concentrate in bonanzas (20% of the total volume of orebodies). The internal deformation is related to the rearrangement of matter in freibergite; exsolution structures in fahlore and native gold are related to postmineral metamor phism. It is suggested that the ore of the Shkol'noe deposit occupies a transitional position between porphyry type and epithermal levels of ore deposition.
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