The activity of landslides on the cliff coast on the Wolin Island under the influence of hydrometeorological events with high morphogenetic potential (Bay of Pomerania – Southern Baltic)

Artykuł prezentuje wyniki badań nad aktywnością procesów osuwiskowych na wybrzeżu klifowym wyspy Wolin wywołanych silnymi wezbraniami sztormowymi oraz intensywnymi opadami atmosferycznymi. Badania opierały się na studium pięciu przypadków dotyczących wykształcenia lub przeobrażenia osuwisk klifowych. W wyniku przeprowadzonej analizy zaproponowane zostały wartości progowe odporności systemu stokowego na oddziaływanie takich czynników morfogenetycznych jak wezbrania sztormowe i opady atmosferyczne. W przypadku przekroczenia wymienionego czynnika wartości progowej w obrębie klifu dochodzi do wykształcenia osuwiska. Należy nadmienić, iż inicjacja procesu osuwiskowego warunkowana jest także wieloma innymi czynnikami, które najczęściej mają charakter wybitnie lokalny (morfologia, litologia, hydrogeologia, itd.). Wobec powyższego należy stwierdzić, iż przedstawione wartości progowe są wartościami koniecznymi do wystąpienia procesów osuwiskowych, jednak z uwagi na złożoność tych procesów, w niektórych przypadkach mogą one nie stanowić wartości wystarczających.The paper presents results of research on the activity of landslides on the Wolin Island cliff coast caused by storm surges and intense rainfall events. The study was based on the analysis of five cases of initiation or transformation of cliff landslides. As a result of the analysis the treshold values of storm surges and precipitation were proposed. Exceeding the threshold values results in a landslide. It should be noted that the process of landslide initiation is conditioned also by many other factors that are most often very local (cliff morphology, lithology, hydrogeology etc.). Therefore, it must be concluded that proposed threshold values are necessary for the occurrence of landslides, but due to the complexity of these processes, in some cases, they may not provide sufficient value

Aktywność procesów osuwiskowych na wybrzeżu klifowym wyspy Wolin w warunkach oddziaływania zdarzeń hydrometeorologicznych o wysokim potencjale morfogenetycznym (Zatoka Pomorska – Bałtyk Południowy)

Artykuł prezentuje wyniki badań nad aktywnością procesów osuwiskowych na wybrzeżu klifowym wyspy Wolin wywołanych silnymi wezbraniami sztormowymi oraz intensywnymi opadami atmosferycznymi. Badania opierały się na studium pięciu przypadków dotyczących wykształcenia lub przeobrażenia osuwisk klifowych. W wyniku przeprowadzonej analizy zaproponowane zostały wartości progowe odporności systemu stokowego na oddziaływanie takich czynników morfogenetycznych jak wezbrania sztormowe i opady atmosferyczne. W przypadku przekroczenia wymienionego czynnika wartości progowej w obrębie klifu dochodzi do wykształcenia osuwiska. Należy nadmienić, iż inicjacja procesu osuwiskowego warunkowana jest także wieloma innymi czynnikami, które najczęściej mają charakter wybitnie lokalny (morfologia, litologia, hydrogeologia, itd.). Wobec powyższego należy stwierdzić, iż przedstawione wartości progowe są wartościami koniecznymi do wystąpienia procesów osuwiskowych, jednak z uwagi na złożoność tych procesów, w niektórych przypadkach mogą one nie stanowić wartości wystarczających.The paper presents results of research on the activity of landslides on the Wolin Island cliff coast caused by storm surges and intense rainfall events. The study was based on the analysis of five cases of initiation or transformation of cliff landslides. As a result of the analysis the treshold values of storm surges and precipitation were proposed. Exceeding the threshold values results in a landslide. It should be noted that the process of landslide initiation is conditioned also by many other factors that are most often very local (cliff morphology, lithology, hydrogeology etc.). Therefore, it must be concluded that proposed threshold values are necessary for the occurrence of landslides, but due to the complexity of these processes, in some cases, they may not provide sufficient value

Design and first cold test of BNL superconducting 112 MHz QWR for electron gun applications

Brookhaven National Laboratory and Niowave, Inc. have designed, fabricated, and performed the first cold test of a superconducting 112 MHz quarter-wave resonator (QWR) for electron gun experiments. The first cold test of the QWR cryomodule has been completed at Niowave. The paper discusses the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule for future experiments. A quarter-wave resonator concept of superconducting RF (SRF) electron gun was proposed at BNL for electron cooling ion/proton beams at RHIC. QWRs can be made sufficiently compact even at low RF frequencies (long wavelengths). The long wavelength allows to produce long electron bunches, thus minimizing space charge effects and enabling high bunch charge. Also, such guns should be suitable for experiments requiring high average current electron beams. A 112 MHz QWR gun was designed, fabricated, and cold-tested in collaboration between BNL and Niowave. This is the lowest frequency SRF gun ever tested successfully. In this paper we describe the gun design and fabrication, present the cold test results, and outline plans for the cryomodule upgrade for future experiments

Superconducting 112 MHz QWR electron gun DISCLAIMER SUPERCONDUCTING 112 MHZ QWR ELECTRON GUN*

Abstract Brookhaven National Laboratory and Niowave, Inc. have designed and fabricated a superconducting 112 MHz quarter-wave resonator (QWR) electron gun. The first cold test of the QWR cryomodule has been completed at Niowave. The paper describes the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule. Future experiments include studies of different photocathodes and use for the coherent electron cooling proof-of-principle experiment. Two cathode stalk options, one for multi-alkali photocathodes and the other one for a diamond-amplified photocathode, are discussed

Superconducting 112 MHz QWR electron gun

Brookhaven National Laboratory and Niowave, Inc. have designed and fabricated a superconducting 112 MHz quarter-wave resonator (QWR) electron gun. The first cold test of the QWR cryomodule has been completed at Niowave. The paper describes the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule. Future experiments include studies of different photocathodes and use for the coherent electron cooling proof-of-principle experiment. Two cathode stalk options, one for multi-alkali photocathodes and the other one for a diamond-amplified photocathode, are discussed. A quarter-wave resonator concept of superconducting RF (SRF) electron gun was proposed at BNL for electron cooling hadron beams in RHIC. QWRs can be made sufficiently compact even at low RF frequencies (long wavelengths). The long wavelength allows to produce long electron bunches, thus minimizing space charge effects and enabling high bunch charge. Also, such guns should be suitable for experiments requiring high average current electron beams. A 112 MHz QWR gun was designed, fabricated, and cold-tested in collaboration between BNL and Niowave. This is the lowest frequency SRF gun ever tested successfully. In this paper we describe the gun design and fabrication, present the cold test results, and outline our plans. This gun will also serve as a prototype for a future SRF gun to be used for coherent electron cooling of hadrons in eRHIC

DESIGN AND PRELIMINARY TEST OF THE 1500 MHZ NSLS-II PASSIVE SUPERCONDUCTING RF CAVITY

NSLS-II is a new ultra-bright 3 GeV 3rd generation synchrotron radiation light source. The performance goals require operation with a beam current of 500mA and a bunch current of at least 0.5mA. Ion clearing gaps are required to suppress ion effects on the beam. The natural bunch length of 3mm is planned to be lengthened by means of a third harmonic cavity in order to increase the Touschek limited lifetime. Earlier work described the design alternatives and the geometry selected for a copper prototype. We subsequently have iterated the design to lower the R/Q of the cavity and to increase the diameter of the beam pipe ferrite HOM dampers to reduce the wakefield heating. A niobium cavity and full cryomodule including LN2 shield, magnetic shield and insulating vacuum vessel have been fabricated and installed. A passive SRF 3rd harmonic cavity consisting of two tightly coupled cells has been designed and fabricated for NSLS-II. Initial cold tests of this cavity are very promising. These tests have verified that the cavity frequency and mode separation between the 0 and {pi}-modes can be set at manufacture. Further, the frequency separation can be maintained over wide tuning ranges necessary for operation. Future work includes HOM damper and motorized tuner development