Query: fig 4 sec in pesaran gap

Candidate papers:

abstract: Two dimensional (2D) materials have begun to impact the field of semiconductor quantum optics through the demonstration of stable quantum emitters in both transition metal dichalcogenides [1] and hexagonal boron nitride (hBN) [2] Single photon emitters (SPE) in hBN are associated with atom like defects that confine electronic levels deep within the wide band gap. As recently reported, the emission energy of these emitters spans over a large spectral band [3] which presents a central problem for developing identical single photon sources. Furthermore, exfoliated hBN flakes show high background emission that reduces single photon purity. We propose a material processing based on ion irradiation and high temperature annealing that allows to reduce the broadband background emission and therefore to isolate individual defects, as shown in the photoluminescence map of Fig.1a. Our sample fabrication process sharply improves the single photon purity with g(2)(0) 0.077, and brightness with emission rate exceeding 107counts/sec at saturation (see Fig.1b) To investigate the wide span of the emission energy, we transfer hBN films, after sample treatment, onto a bendable substrate that allows us to controllably apply strain, confirming also that quantum emitters persist this transfer process. Fig.1c plots the emission spectra of two SPEs for compressive, tensile and no strain. These emitters show different tuning coefficients up to 6 meV per strain unit. The strain control of the emission wavelength and the reduced multi photon emission probability produce a tunable ultra bright room temperature single photon source with the advantages of 2D materials, including stretchability, heterogeneous device assembly and straightforward integration with photonic circuits [4]
author_names: Hyowon Moon

Benjamin Lienhard

Sajid Ali

Marco M Furchi

Michael P Walsh

Dmitri K Efetov

Pablo Jarillo-Herrero

Michael J Ford

Igor Aharonovich

D Englund
title: Tuning the ultra bright quantum emission from atomic defects in hexagonal Boron Nitride
year: 2017

abstract: We are pushing forward the developmentof a pulsedmagnet that has a combined structure of magnet coils with a ceramic vacuum chamber, aiming to realize a small gap. The structure we are developing is that single turn air coils are implanted along the longitudinal axis in the cylindrical ceramic chamber wall with thickness of 5 mm. The ceramic wall works for separating the vacuum from the atmosphere, as well as holding the coil structures mechanically and the electrical insulation of coils. We achieved the continuous operation over 200 days, without any failure, of currentexcitation with 20 kV/7.7 kA pulse with 4 msec width and repetition of 1Hz, using the dipole type prototype with the bore radius of 30 mm and the magnetic length of 0.3 m in 2013, whilemaintaining the vacuumpressure less than 10 6 Pa. MERITS OF NARROW GAP MAGNET The performances which are required in common to all pulsed magnet system are fast, strong, and high repeating pulsed magnetic field characteristics. In order to achieve these performances, there are two approaches. First one is developing a high power and high repetition pulsed power supply. Second one is reducing the power supply load as low as possible. The load reduction is an important issue. Because, if we try to achieve these performances without decreasing the load, the power supply system will have a large body size, consequently, need a huge installation space and give a restriction to the installation place of the system. One of the best solutions to lower the power supply load is reduce themagnet pole gap. The kick angle is determined by the magnetic filed strength and field length. By the increased magnetic field with reducing the pole gap, the field length becomes shorter while keeping the kick angle the same. As a result, the coil inductance, hence the pulsed power supply load, become small. The low coil inductance is effective to achieve short pulse width and high repetition rate, in addition, to make the power supply small. The compact magnet and small power supply give the flexibility for setting position in an accelerator, making the kick efficiency optimum with the appropriate beta function value position. Compact pulsed magnet with a narrow gap will fit to the future light source ring like generating diffraction limit synchrotron radiation [1] Because the storage ring chamber size will be reduced in order to match the ultra low beam emittance and there is no enough space to install the pulsed mitsuda@spring8.or.jp magnet due to a large number of optical magnets. Additionally, it also will fit to small size storage rings that will require narrow installation spaces for these kinds of devices involving the injection kickers and correction kickers, and that have short revolution period requiring shorter pulse width. CERAMIC CHAMBER INTEGRATION DESIGN AND THE ADVANTAGE Figure 1: Design of dipole type CCIPM for the fabrication. In an ordinary pulsed magnet, a ceramic chamber is used as a beam duct to reduce the eddy current effect for a pulsed magnetic field. Usually, the ironor ferrite core is set up outside of the ceramic chamber so that its magnetic poles sandwich the ceramic chamber. In this case, the distance(=magnet gap) between a magnetic pole and the beam is decided by the ceramic chamber bore radius, chamber thickness and clearance between the chamber and the pole. It is impossible to close the gap to the beam less than this restriction. On the other hand, in an air coil type pulsed magnet, the coil is set up on the surface of the ceramic chamber so that its poles hold a ceramic chamber, or inside of the ceramic chamber like a strip line kicker with complex supports. In the former case, the magnet gap is restricted by the ceramic chamber size. In the latter case, the complex support and coils cause an impedance unmatching of the beam wall current and increasing the chamber diameter to include the complex structures inside the chamber. To improve these insufficient aspects simultaneously, a ceramic chamber integrated type pulsed magnet was figured out. The structure we are developing is that single turn aircoils are implanted along the longitudinal axis in the cylindrical ceramic chamber wall with thickness of 5 mm. For a dipole type magnet, four metallic bars =coil) are totally implanted and one of bars is connected with another bars so that one pair of bars makes a coil. Implanting hole completely penetrates the chamber wall and is blocked up with the metallic bars. Figure 1 shows cross sectional view of Proceedings of IPAC2015, Richmond, VA, USA WEPMA049 7: Accelerator Technology T16 Pulsed Power Technology ISBN 978 3 95450 168 7 2879 Co py rig ht (c) 20 15 CC B Y3. 0 an d by th er es pe ct iv ea ut ho rs Figure 2: The distribution of a magnetic field strength with DC 1000A exciting current for the CCIPM design of Fig. 1. the dipole type design of the Ceramic Chamber Integrated Pulsed Magnet (CCIPM) We started actual development with KYOCERA Co. Ltd. in 2012. The bore radius is 30 mm and the magnet length =coil length) is 300 mm to match the SPring 8 bumpmagnet size. The coil is arranged at 30 degrees from the median plane in order to achieve the dipole field uniformity within 0.1% and maximize the field strength in the center of magnet. Figure 2 shows the field strength distribution for the actual coil arrangement of Fig. 1. The arc shape metal bars connect each pair of coils at the coil end along the ceramic circumference by the conductive epoxy resin in the prototype. By this way, the endcoils stand up naturally and the irregularity of the field at the magnet end is reduced by about 30 compared with no stand ups. One of the arc type bars works as a busbar which connects feeder lines from the pulsed power supply. There are two technical advantages by applying this CCIPM structure. First one is that the ceramic wall works for separating the vacuum from the atmosphere, as well as holding the coil structures mechanically and the electrical insulation of coils. By this structure, magnet pole edges can be set close to the inside diameter of the chamber. Seeing from inside of the ceramic chamber, the pole edges put on the inside surface of it and does not bulge from the surface level. Therefore, the pole edges are put close to the beam without disturbing the beam impedance. Second one is that the air coils are arranged around the circle on the ceramic inside surface to optimize the magnetic field strength and uniformity. There is no structural restriction to arrange the coil and not any complex coil supporting structure. As a whole, a pulsed magnet will be built with the extremely simple components which do not bulge inside and outside of the ceramic chamber. SUBJECTS TO THE FABRICATION The followings are important subjects about the CCIPM fabrication. Implanting multiple coils simultaneously along longitudinal axis over the 0.3 m. Keeping the super high vacuum tightwith the pressure of less than 1.3x10 11 Pa*m3/s. Enduring 0.1 MPa atmospheric pressure and magnetic field stress produced by the current more than 5 kA. Precisely arranging the coil with 10 mm along longitudinal axis. Ensuring the vacuum tightness under the thermal cycle stress up to 800 degrees. After the copper coils are implanted in the penetrated holes of the ceramic wall, it is bounded by silver brazing with a curing process at 800 degrees. It is the key technique in this development to implant the coil into the ceramic under the condition of the different thermal expansion rate along the longitudinal axis. To establish coil implanting technique, two development stages were taken as follows; firstly, optimization was done to reduce the residual strain, using the ceramic plate test piece, the coil shape and material, silver brazing volume, curing procedure and curing jig. Secondary, implanting technique established by test piece was expanded to the cylindrical ceramic chamber. In the Figure 3: A test piece sample with a typical huge crack. first stage, many vacuum leaks occurred by minute cracks around the coil end part inside and outside of the ceramic. Figure 3 shows the test piece and typical crack. The test pieces without vacuum leak experienced the curing process of 800 degrees again, and the vacuum tightness was confirmed to be kept. In the second stage, there was no product with vacuum leaks for both of two prototype products. However, when the flange sleeve was bounded to the ceramic by silver blazingwith 800 degrees in vertical posture, the silver solder which bounded coils was welded again and vacuumtightness broke. The newmethod that bind the ceramic and flange sleeves in horizontal posture was developedwith success. Finally, we succeeded in building the dipole type pulsed magnet prototype in 2013. The vacuum tightness under detection limit of 1.3x10 11 Pa*m3/s of He leak checker was achieved with flanges bound. RELIABILITY AND PERFORMANCES Continuous Operating We achieved the continuous operation over 252 days from 2013 to 2014 as shown in Table 1, without any failure, of current excitation by the current of 7.7 kA with 20 kV source with 4 m sec width and repetition of 1 Hz and with thermal cycle repetition. Figure 5 shows the conditioning setup before ribbon heaters were wrapped. The thermal cycle temperature was selected as from 30 degree celcius to 80 degrees. The 80 degrees was actually measured temperWEPMA049 Proceedings of IPAC2015, Richmond, VA, USA ISBN 978 3 95450 168 7 2880 Co py rig ht (c) 20 15 CC B Y3. 0 an d by th er es pe ct iv ea ut ho rs 7: Accelerator Technology T16 Pulsed Power Technology Figure 4: The inner surface view of the complicated CCIPM. ature on a ceramic chamber surface under the stored beam current of 100 mA in SPring 8 storage ring. The applied thermal cycle procedure was like followings: the chamber surface temperature was heated till 80 degrees from the room temperature (30 degrees) without ramp up rate control, then the 80 degrees was
author_names: Teruo Honiden

Noritaka Kumagai

Tatsuro Nakanishi

Atsushi Sasagawa

S Sasaki
title: Development of the Ceramic Chamber Integrated Pulsed Magnet Fitting for a Narrow Gap
year: 2015

abstract: The Hell Gap point, excavated from a cultural level dated by radiocarbon at 8890 B.C. (10,850+550 B.P. is described by H. M. Wormington. It represents the oldest known cultural level at Hell Gap, an extensive multicomponent quarry site occupied by paleo Indian groups over a considerable period of time. IN THE HELL GAP valley of east central Wyoming, some 13 miles north of the town of Guernsey, a series of sites or stations containing paleo Indian assemblages are being excavated by a crew of University of Wyoming students under my direction and with the support of the American Philosophical Society. At the Kimball station (SE1/4, SE1/4, SE/4, Sec. 10, T28N, R65W) an Agate Basin horizon has been found overlying a cultural zone radiocarbon dated at 8890 B.C. (10,850 550 B.P. Isotopes Inc. This early deposit contains a type of projectile point for which the name Hell Gap is proposed (Fig. 1) H. M. Wormington, who has given valuable technical aid throughout the project, describes the point type as: a lanceolate form, reminiscent of the Agate Basin type, yet different enough to be regarded as a separate point type. Of the six whole and fragmentary points recovered, three have so marked a basal constriction that they may be considered as essentially stemmed. Bases are straight or slightly convex. Cross sections range from relatively thin ovals to almost diamond shaped. Flaking was by carefully controlled percussion. Pronounced basal grinding is present along the constricted portion. Size range of whole points is from 60 to 88 mm. For purposes of comparison, plastic casts of a Hell Gap point may be obtained from the Denver Museum of Natural History. The Warrick station (NW1/4, SEY4, SE4, Sec. 10, T28N, R65W) lies within the same valley but several hundred yards southeast from the Kimball excavations. At the Warrick site there is a highly productive Agate is point, for example, B.P. (1948) B.P. (1961) if they sist in this habit. ere are already enough problems with radioc rb n e figures without adding more. In fact, s the years ss, there will be reason to reg t that m ny of the ted age figures wer not published toge her with the Basin horizon but no well defined Hell Gap level. In a lower cultural horizon which appears to correlate with the Hell Gap stratum at the Kimball site was found a fragmentary point which has the general outline, thin cross section, and fine flaking of a Folsom point, but whic is unfluted. The radiocarbon date of 8820 B.C. (10,780 B.P.+375) for Folsom at the Lindenmeier site (Haynes and Agogino 1960) and the Hell Gap date are essentially compatible. Geological investigations of the Hell Gap area are being conducted by Vance Haynes. Preliminary work reveals that a loess sequence containing paleosols and disc nformities overlies gravels and silts that presumably rest on bedrock. A marked erosional unconformity and paleosol within the loess sequence is interpreted as representing Two Creeks time. This is supported by the radiocarbon date of 8890 B.C. from the Hell Gap occupation level which rests on the unconformity. Other pertinent Pleistocene and Recent climatic events are believed to be represented in the stratigraphy and geomorphology of the Hell Gap area. Points of the Hell Gap type, although not previously defined, have been noted as occurring as isolated finds in Canada and various parts of the United States. They are a minor component in the Russell A. Johnston collection, gathered near Cereal in southern Alberta from blowouts which also yielded Agate Basin points, artifacts of the Cody Complex, and Alberta points. The latter resemble Scottsbluff, but are wider and longer with more pronounced stems and rounded bases. Few Hell Gap points have been recorded from Montana and Idaho, but such points are relatively common in eastern sections of Wyoming and Colorado and can be occasionally found in the central and western parts of these states as well. Hell Gap points were noted in the surface collections of Merrill Potter, Earl White, and James Duguid of Wyoming, and among the artifacts collected by Bert Mountain and the late Perry Andersen of Colorado. In New Mexico, points typologically similar to Hell Gap are referred to as J points by local collectors. Jpoints differ from Hell Gap points by having greater body to stem width (although there is considerable overlap) and a tendency to unground lateral edges. Fred Wendorf and Tully H. Thomas (1951: 108 9) report finding a point of Hell Gap type in an erosional blowout that also produced Folsom material near Concho, Arizona (Wendorf and Thomas 1951, Fig. 47) Since Folsom Hell Gap material can only be found in this region in blowouts that cut into pre altithermal strata, Wendorf (Wendorf and Thomas 1951: 109) suggests that this paleo Indian occupation probably preceded the erosional cycle which is attributed to the post glacial optimum. This Altithermal erosional cycle is believed to have commenced about 5000 B.C. giving a minimum date for Folsom Hell Gap material in the region. Lake Mohave points from southern California are generally cruder but are reminiscent in outline of Hell Gap material. Lake Mohave points are found in mixed izo but no wel defined Hell Gap level. In a l ral horizon which ap ears to cor elate with ll a stratu at the Kimball site was found a a point which has the general outline, thin io and fine flaking of a Folsom point, but 558 VOL. 26, No. 4, 1961 This content downloaded from 207.46.13.52 on Mon, 24 Oct 2016 04:10:54 UTC All use subject to http:/about.jstor.org/terms
author_names: George A Agogino
title: A New Point Type from Hell Gap Valley, Eastern Wyoming
year: 1961

abstract: We have been improving the Main Ring (MR) for the beam power of 750 kW which is first goal of MR in J PARC. The repetition period of the Fast eXtraction (FX) must be shorten to 1.3 sec from the current period of 2.48 sec for the increasing the beam power. We have been upgrading injection and FX magnets. We have exchanged an injection septum magnet which were located at the injection line from RCS to MR and its power supply in summer 2016. In this paper, we describe the final results of the measurement of the gap field, leakage field. We also describe the result the beam study for evaluation of the effect by the leakage field of the new injection septum magnet. NEW INJECTION SEPTUM MAGNET SYSTEM Figure 1: The schematic of the Injection Magnets group in MR in J PARC. The beam power in FX operation of J PARC MR have achieved 470 kW in Mar. 2017. For upgrading to 750 kW, which is our first goal of the beam power, we need to increase beam intensity and extraction repetition. The present repetition period is 2.48 sec and our first goal is 1.3 sec. We have been upgrading the Injection and FX magnet systems for the high power beam. The schematic chart of the present Injection magnets in the MR are shown in Fig. 1. These magnets inject the 3 GeV proton beam from the RCS1 into the MR in 120 msec. There is an injection septum magnet, which the field of the previous one was 1.44 Tesla and integrated field (BL) was 2.81 T*m and the bending angle was 220 mrad for beam operation. We are calling it High Field Septum Magnet(HF Inj Septum) The replacement of the HF Inj Septum is one of the project of the upgrading to high power beam. We have finished the replacement of the HF Inj Septum into the MR in summer 2016. The detail of the motivation and its specification were described in [1] The tatsunobu.tshibata@j parc.jp 1 Rapid Cycling Synchrotron final figure of the HF Inj Septum after installation of the new injection and circulating duct is shown in Fig. 2 2. Figure 2: The photogtaphs of the new HF Inj Septum which were assembled in early of Jlu 2016. FINAL EVALUATION OF THE NEW HF INJ SEPTUM Measurement of Gap Field Figure 3: The original and corrected pattern(Left) and results of BL with the corrected patterns(Right) The final measurement of the gap field and leakage field along the circulating line was conducted in end of July 2016. We used the search coils for measurement of gap field, and used hole sensor for measurement of leakage field. The BL were calculated by using waveforms of magnetic field which were measured along the tracks. One of the important is flatness of the BL at flat top of the current pattern. The orignal current pattern waveform had perfect flatness at the flat top, but the flatness of its BL was not perfect due to the induced field which is generated by eddy current on the surface of the injection duct. We made the corrected current patterns for cancelling of the effect of the eddy current. The Figure 3 shows the original and corrected current pattern waveform(left) and the BL with corrected patterns of 2 We produced a new inejcton duct and circulating duct in Mar. 2016 [1] MOPIK034 Proceedings of IPAC2017, Copenhagen, Denmark ISBN 978 3 95450 182 3 576 Co py rig ht (c) 20 17 CC B Y3. 0 an d by th er es pe ct iv ea ut ho rs 04 Hadron Accelerators T12 Beam Injection/Extraction and Transport Figure 4: The Gap field(Left) and the correlation between the BL and the setting current(Right) which the current were varied from 2,300 A to 3,400 A. The vertical axis is normalized with the BL value at the end of flat top. All of flatness achieved below 5x10 5. The gapfield distribution along the track of center of beam with the corrected patterns and the correlation between the measured the BL and the setting current are shown in Fig. 4. In the left figure, the maximum magnetic field with 2,300 A and 3,400 A were 1.32 Tesla, 1.78 Tesla, respectively 3. In the right figure, the red line means a straight line and a blue line means fitting line. We could see that the correlation has good linearity below the 2,800 A, by contrast we could see that the saturation of BL above 2,800 A. The design BL with the previous magnet was 2.81 T*m. The current for the beam operation was estimated 2,590 A which corresponds with 2.81 T*m. The bending angle was estimated 221 mrad. Measurement of Leakage Field We have constructed the triple magnetic shields for reducing the leakage field along the circulating beam line. The most inner shield is the circulating duct itself of which the material is pure iron [1] and another two shields are also pure iron which are covering the circulating duct(Fig. 5(Upper) We have measured the leakage field on three tracks of which the length were about 4.5 m along the circulating duct. The mapping and the BL with 2,700 A and 3,400 A are shown in Fig. 5, where the position of 0 mm was at the edge of downstream of the magnet. The magnetic field in the figures means the average value in 120 msec time window for beam injection, and the positive direction of the field was defined as down to up. In case of 2,700 A, the maximum leakage along the circulating duct on the center of track was about 0.5 Gauss. We could see the multi pole field component by the dependence on the distance from the septum plate. We detected about 7 Gauss leakage on the center track in the upstream region from the edge of the circulating duct. The source of the large field is magnet coil at injection port which has no shield such as field clamp. These BL were calculated in the extent from 124 cm to +250 cm along each track. According to the results(Fig. 5(right) the BL in beam injection time window with 2,590 A and 3400 A 3 The maximum field of the previous one was 1.47 Tesla Figure 5: The vertical leakage field and its BL with 2590 A(Upper) and 3400 A(Lower) where the leakage field was calculated as average in beam injection time. We did not intergate the region above +250 cm, because a QM is located at this position in real beam line. were 0.1 mT*m and 0.4 mT*m, respectively. On the other hand, the BL in beam acceleration time window were about 0.2 mT*m. These BL with the new magnet are smaller than that with the previous magnet From above, we could confirm that the leakage field was enough lower than that of the previous. Consumption Power with 1 Hz Operation We summarize the results ofmeasurement of consumption power of the power supply and joule heat of the magnet coil under 1 Hz operation. The consumption power with 2,590 A and 3,400 A were 140 kW and 240 kW, respectively. The joule heat were 63 kW and 200 kW. We estimated the consumption power with 2,590 A under 2.48 sec repetition, which is present MR beam operation condition, as 56 kW, and it was about half of that with previous power supply. The consumption power with previous power supply under same condition was about 100 kW. THE BEAM OPERATION WITH THE NEW HF INJ SEPTUM After the final measurement of the magnetic field, we replaced the original HF Inj Septum and its power supply Proceedings of IPAC2017, Copenhagen, Denmark MOPIK034 04 Hadron Accelerators T12 Beam Injection/Extraction and Transport ISBN 978 3 95450 182 3 577 Co py rig ht (c) 20 17 CC B Y3. 0 an d by th er es pe ct iv ea ut ho rs with new. Figure 6 and 7 show the new magnet and the power supply which were installed in MR. Figure 6: The new HF Inj Septum which were installed in the beam line in MR in summer 2016. Figure 7: The new power supply of the HF Inj Septumwhich were installed in power supply building in MR area. The beam operation with the new HF Inj Septum was started in Oct. 2016. The latest operation current which were optimized by injection beam tuning, in Apr. 2017, is 2,598 A. The one of the most important is the potential of the leakage field to impact the circulating beam. We have evaluated the impact by monitoring the position of the circulating beam during beam study of MR in Nov. 2016. The beam position was measured with a Beam Position Monitor(BPM) which are located near the HF Inj Septum. In the beam study, we changed the time width of flat top of the pattern current for HF Inj Septum from 0.2 sec to 0.4 sec. The time variation of the beam position measured by the BPM is shown in Fig. 8. The HF Inj Septum exicited until 550 msec in the left figure. We could see that the beam position was 0.2 mm during no leakage time region. On the other hand the beam position was 0 mm during flat top of the HF Inj Septum, furthermore the beam position changed about 0.4 mm during fall time. The kick angle(BL) corresponds with the 0.4 mm shift was estimated approximately 2.5 mT*m with SAD, so the kick angle consistent with the results of the measurement of leakage field. The kick angle is not serious problem for the present beam condition, but we plan to install the additional shield for reducing the leakage as much as possible. However, we must be careful the leakage field of a QMwhich is located at the upstream of HF Inj Septum. Because about 200 Gauss leakage field from the QM also exists in same area. The rejection of the leakage field of the QM can not be permitted, because the beam condition are optimized including the leakage. So, we are making the design of the additional shield for rejecting only the leakage field from the magnet coil of HF Inj Septum. We plan to produce the additional shield by summer 2017. Figure 8: The shift of the beam position which was measured with BPM due to the leakage field of the injection septum.
author_names: Tatsunobu Shibata

Kuanjun Fan

Koji Ishii

Hiroshi Matsumoto

Noriyuki Matsumoto

Takuya Sugimoto
title: The New High Field Injection Septum Magnet System for Main Ring of J PARC
year: 2017

abstract: 1190 Discovery Gap located at 37deg N, 16deg W is known as the terminal point of Antarctic Bottom Water spread ing with a potential temperature less than 2degC. Only warmer water has been found north of this gap. This paper presents the results of measurements of temper ature, salinity, and currents in the gap performed in October 2011. A comparison is made with the mea surements of British oceanographers [3] from 1982. Antarctic Bottom Water formed over the continen tal slope of Antarctica propagates over long distances to the north through abyssal basins of the Atlantic Ocean and abyssal channels connecting these basins [2] Starting from 2002, the Shirshov Institute of Oceanology, Russian Academy of Sciences, has been carrying out studies of Antarctic waters in the deep channels of the Atlantic, namely, the Vema Channel (31deg S) the Romanche Fracture Zone (equator) Kane Gap (9deg N) and Vema Fracture Zone (11deg N) In October 2011 during the expedition on R/V Aka demik Sergei Vavilov, a new set of investigations was performed in Discovery Gap. The ridge located in the East Azores Fracture Zone located at 37deg N is considered the terminal point for Antarctic Bottom Water spreading as the water that is defined as water with a potential temperature below 2degC [5] Water exchange between the Madeira and Iberian deep water basins occurs through Discov ery Gap located in this ridge at 16deg W (Fig. 1) The depth of both basins exceeds 5300 m. The length of Discovery Gap is approximately 150 km, and the width is 10 50 km (along the 4500 m isobath; Fig. 1) Based on the bottom topography database [4] (version V14.1) the gap has three sills with close depths from 4680 to 4711 m. Their location is shown in Fig. 1. The slope of the gap walls exceeds 1/5 [3] The first detailed studies in the region of Discovery Gap were carried out in 1982 [3] Several CTD sec tions were occupied, and six long term moorings with 10 current meters were deployed during these studies. Neutral floats were released in the bottom layer at a depth of approximately 4700 m, which were traced for 10 days. The mean water transport based on the data in [3] which gives analysis of these data, was directed to the northeast along the channel. The velocities were approximately 5 cm/s. The transport of water with tem peratures less than 2.05degC from the Madeira Basin to the Iberian Basin was estimated in the paper at 0.2 Sv. In order to save the ship time, the section in 2011 was located in the narrowest place of Discovery Gap practically on the line of one of the sections in 1982 west of the eastern sill of the gap (Fig. 1) to have the possibility of comparing the data. A survey of bottom topography was performed before the measurements in October 2011 to locate the profiling stations more carefully. Profilings at three CTD stations over a sec tion 20 km long (Fig. 1) were made using an SBE 19 profiler combined with a lowered current profiler RDI WHS (300 kHz) Figure 2 shows a section of potential temperature (2011) across Discovery Gap. In general, the section repeats the characteristic features of the section in 1982. Elevation of all isotherms by approximately 200 250 m is notable, which indicates the integral cooling of the flow. The dotted line in Fig. 2 shows for comparison the 2.02degC isotherm based on the data in [3] Over the 29 years that have passed, the minimal temperature on the section decreased by almost a hun dredth of a degree from 2.011degC in 1982 to 2.002degC in 2011. As in 1982, the cold core is displaced to the eastern slope. The vertical temperature gradient at depths of 4000 m changes to a mixed layer in the deeper layers of the gap. The salinity distribution dem onstrates a similar displacement of fresher water to the eastern slope. The data of the lowered ADCP were processed using the programming package for LADCP, version IX.7. The results of processing demonstrated low current veloci ties compared with the velocities of the barotropic tide. A correction for the tidal velocities was calculated Discovery Gap: The Terminal Point of Antarctic Bottom Water Spreading
author_names: Eugene G Morozov

R Yu Tarakanov
title: Discovery gap: The terminal point of antarctic bottom water spreading
venue: Doklady Earth Sciences
year: 2012

abstract: We are improving the Main Ring (MR) for beam power of 750 kW which is the first goal of J PARC. The repetition period of the Fast eXtraction(FX) must be short to 1.3 sec from the current period of 2.48 sec for the improvement of the beam power. It is necessary to exchange a high field injection septum magnet which will be installed at the injection line from RCS to MR and its power supply, because the current injection septum system can not be operated with 1.3 sec repetition. Since confirmed the large leakage field around current circulating beam line of the injection magnet, we must improve the shielding structure which make low leakage field. We started the development of the new injection septum magnet and its power supply in 2013. It can operate with 1 Hz repetition and the low leakage field which its order is 10 4 of the gap field. The new Injection septum magnet and the new power supply were constructed in 2014. We had many improvement of the magnet and power supply. We will install the new injection septum magnet system in this summer. In this presentation, we will report the detail of the results of its performances. NEW INJECTION SEPTUM MAGNET SYSTEM Figure 1: The schematic of the Injection Magnets group in MR. The beam power for FX mode of J PARC MR achieved 395 kW in Feb. 2016. For 750 kW in which our first goal of the beam power, we need to increase beam intensity and extraction repetition. The present repetition period is 2.48 sec and our goal is 1.3 sec1. We are upgrading the Injection and FX magnet systems for the high power beam. The schematic chart of the present Injection magnets in the MR are shown in Fig.1. These magnets in* tatsunobu.tshibata@j parc.jp 1 We are calling it as 1 Hz operation. ject the 3 GeV proton beam from the RCS2 into the MR in 120 msec. The first injection septum magnet of which the field is 1.44 Tesla(BL=2.81 T*m) bends the proton beam 220 mrad. We are calling it as High Field Septum Magnet(HF Inj Septum) There are several reasons of necessity of a new HF InjSeptum. The main reason is the present power supply(P.S. can not operate with 1 Hz. The present P.S. outputs a pattern current of which the rise time is 0.25 sec, flat top time is 0.2 sec, and the fall time is approximately 1 sec. The source of such a long fall time is that the output inverter unit has 1 IGBT and it does not control negative voltage. The joule heat at the coil will increase by 1 Hz operation, and the size of its hollow must be larger than present size, ph4.8 mm. The second reason is the beam duct needs more large aperture for the high power beam. The aperture of the present injection duct is 150 mm(H)x80 mm(V) but it is not enough size for high power beam emittance such as 80p. The third reason that he leakage field around downstream region of the beam duct is still high for high power beam, and we need to reduce more. The present HF Inj Septum has two magnetic poles of which the length is 900 mm each other, and the leakage field exists at the opening space of them [1] The current for normal operation is 2800 A, but since the maximum current is 2900 A the present P.S. can not operate for 3.3 GeV injection which is one of the future plan. The important requirements for the new are 1 Hz operation, large aperture, low leakage field, and high current for 3.3 GeV injection. We developed a new one which satisfies all of above requirements in 2014. Fig.2 shows the new magnet and components of the P.S. The input AC400 V is rectified to DC480 V by IGBT converter units and charges are stored in the capacitor units. The output inverter units have 4 IGBT units and it can output negative voltage to control its fall time. The rise, flat top and fall time with the new P.S. are all 0.2 sec. The digital feedback system is used for high stability of its output current. To reduce its consumption power, the magnetic energy in the inductance of the magnet returns to the capacitors. The new P.S. bases on new power supply for the main magnets of J PARC MR. We also designed a new magnet for resolving above problems. The new HF Inj Septum is "sector" type septum [2] We installed an end field clamp for covering the edge of coils at the exit of the injection duct for reducing the leakage field. The field clamp consists with laminated Si steel sheets which are covered with SUS plates. The new aperture of the injection duct is 180 mm(H)x80 mm(V) We se2 Rapid Cycling Synchrotron Proceedings of IPAC2016, Busan, Korea TUPMR039 04 Hadron Accelerators T12 Beam Injection/Extraction and Transport ISBN 978 3 95450 147 2 1337 C op yr ig ht (c) 20 16 C C B Y3. 0 an d by th e re sp ec tiv e au th or s lected new hollow conductors of which the hollow size are ph6.0 mm. We will install the new HF Inj Septum into the MR in summer 2016. Figure 2: The diagram of the new power supply(Upper) The photograph of the new magnet(Lower) EVALUATION OF THE NEW HF INJ SEPTUM The gap field must be stable and its BL must be flat at flattop. The required reproducibility of the gap field and flatness of the BL are less than 10 4. The leakage field must be less than 1 Gauss which is 10 4 of the gap field. To evaluate the new HF Inj Septum, we measured the gap field and leakage field. We produced some search coils to measure the gap field. The search coil consists of 1,000 turn coils which winds on a ph4 cm diameter non magnetic bobbin. The output voltage of the search coil is proportional to time difference of magnetic field. We also produced X Y Z scanner with three electric sliders for mapping of gap field. We used a gauss meter( model 8030 of F.W.BELL which uses hole sensors to measure the leakage field. The waveforms of field were recorded with a 16 bit ADC board model SL1000 of YOKOGAWA DENKI Its sampling rate was 5 kSamples/sec, and the recorded time window was 1 sec. Measurement of Gap Field and Flatness of BL We measured the BL with 2800 A and 3400 A3 output. The results of the mapping of gap field and its BL are shown in Fig.3, where the 0 mm position was defined as face of upward flange of the injection duct. We confirmed that the measured BL with 2800 A was large than 2.81 T*m, it was enough large for normal MR operation. The flatness, which we defined as the difference of BL between 120 msec which is timing difference of first and last beam bunches injection, were 2.5x10 4 and 4.2x10 4 with 2800 A and 3400 A, respectively. Both of them were large than 10 4 and they did not satisfy our requirements. The main source of problem was effect of magnetic field by eddy current which 3 The current at flat top. Figure 3: The results of the gap field(Left) and BL(Right) were induced at the surface of the injection duct. We made the corrected current patterns for reduction of the effect of eddy current. Fig.4 shows the corrected current pattern for 3400 A and the results of BL with corrected patterns for 2700 A, 2800 A, 3100 A and 3400 A. The vertical axis was normalized with maximum value of BL in flat top. All of results of the flatness were 10 5. Figure 4: The normal and corrected pattern(Left) and results of BL with the corrected patterns(Right) Measurement of Leakage Field We installed some additional inner SUY shields of which their thickness were 5 mm to reduce leakage field in the circulating region. We measured the leakage field at the center of the duct along beam direction. Fig.5 shows the mapping and its BL of leakage field with 2800 A and 3400 A, where the 0 cm position was the edge of magnetic pole. The average means averaged value in 120 msec at flat top and the peak means peak value in beam acceleration time during TUPMR039 Proceedings of IPAC2016, Busan, Korea ISBN 978 3 95450 147 2 1338 C op yr ig ht (c) 20 16 C C B Y3. 0 an d by th e re sp ec tiv e au th or s 04 Hadron Accelerators T12 Beam Injection/Extraction and Transport fall time. The 1.5 Gauss existed at 1.2 m far from the exit of the circulating duct with 3400 A. The leakage field increased at the outside of circulating duct, because of no shield around there. We confirmed that the leakage field with 2800 A was less than 1 Gauss in the circulating duct and it was enough lower than our requirement. The BL with 2800 A was ~1 Gauss*m and it is also less than that of present magnet. The BL with 3400 A in beam injection time was ~4 Gauss*m, it was same as present. Figure 5: The leakage field with 2800 A and 3400 A(Right upper) where(1)Average in injection time with 2800 A (2)Average with 3400 A (3)Peak in Acceleration time with 2800 A (4)Peak with 3400 The BL with 2700 A,2800 A,3100 A,3400 A(Right Lower) The serious vacuum leak at the welding position which were connected the flange and injection duct was happened in Aug. 2015. The main source of the problem could be presumed the structural defect of the edge of the injection duct. We had to redesign a new injection duct to solve its defect. We also decided to redesign a new circulating duct of which the material was SUY. Because the inner SUY shield was very effective, and we wanted to unify the inner shield and circulating duct. The production of the new injection and circulating ducts were completed in Mar. 2016. We have plan to measure the leakage field and BL again with the new ducts. Reproducibility of Current and Gap Field We will describe the reproducibility of the gap field and current. We used output signal of a DCCT, which is used for feedback system, in the output unit of P.S. to measure the current. The output signal of DCCT were converted to current difference by 20 bit AD and DA converters and feedback controller. The current difference means the difference between setting and measurement current. We kept the operation several hours with 0.5 Hz repetition for monitoring its time variation. Only gap field had obvious variation because of thermal expansion of search coil, and we used events only after stabilization for evaluation of reproducibility. The definition of reproducibility is ratio of the r.m.s. a
author_names: Tatsunobu Shibata

Kuanjun Fan

Koji Ishii

Hiroshi Matsumoto

Noriyuki Matsumoto

Takuya Sugimoto
title: The Development of a New High Field Injection Septum Magnet System for Main Ring of J Parc
year: 2016

abstract: The liver is the metabolic center of the mammalian body and serves as a filter for the blood. The basic architecture of the liver is illustrated in figure 1 in which more than 85% of the liver mass is composed of hepatocytes and the remaining 15% of the cellular mass is composed of Kupffer cells (KCs) stellate cells (HSCs) and sinusoidal endothelial cells (SECs) SECs form the blood vessel walls within the liver and contain specialized morphology called fenestrae within in the cytoplasm. Fenestration of the cytoplasm is the appearance of holes ~100 mm) within the cells so that the SECs act as a sieve in which most chylomicrons, chylomicron remnants and macromolecules, but not cells, pass through to the hepatocytes and HSCs 1 (Fig. 1) Due to the lack of a basement membrane, the gap between the SECs and hepatocytes form the Space of Disse. HSCs occupy this space and play a prominent role in regulation and response to injury, storage of retinoic acid and immunoregulation of the liver 2. SECs are among the most endocytically active cells of the body displaying an array of scavenger receptors on their cell surface 3. These include SR A, Stabilin 1 and Stabilin 2. Generally, small colloidal particles less than 230 nm and macromolecules in buffer phase are taken up by SECs, whereas, large particles and cellular debris is endocytosed (phagocytosed) by KCs 4. Thus, the bulk clearance of extracellular material such as the glycosaminoglycans from blood is largely dependent on the health and endocytic functions of SECs 5,6. For example, an increase in blood hyaluronan levels is indicative of liver disease ranging from mild to more severe forms 7. With the exception of one report 8, there are no immortalized SEC cell lines in existence. Even this immortalized cell line is de differentiated in that it does not express scavenger receptors that are present on primary SECs (our data, not shown) All cell biological studies must be performed on primary cells obtained freshly from the animal. Unfortunately, SECs dedifferentiate under standard culture conditions and must be used within 1 or 2 days upon isolation from the animal. Differentiation of SECs is marked by the expression of Stabilin 2 or HARE receptor 9 CD31, and the presence of cytoplasmic fenestration 1. Differentiation of SECs can be extended by the addition of VEGF in culture media or by culturing cells in hepatocyte conditioned medium 10,11. In this report, we will demonstrate the endocytic activity of SECs in the intact organ using radio labeled heparin for hyaluronan for the SEC specific Stabilin 2 receptor. We will then purify hepatocytes and SECs from the perfused liver to measure endocytosis.
author_names: Sandhya Lakshmi Gopalakrishnan

Edward N Harris
title: In vivo Liver Endocytosis Followed by Purification of Liver Cells by Liver Perfusion
venue: Journal of visualized experiments JoVE
year: 2011

abstract: FAIMS MS has been used for the analysis of non covalent complexes formed by 3 MX. The singly charged (3 MX) n (n 4 12) complexes show maximum FAIMS transmission at different CF values, with the optimum CF decreasing as the size of the cluster increases (Fig. 4) 3 Methylxanthine was prepared as a 0.5 mM solution in 60:40 methanol:water with 1 mM ammonium acetate, or with 1 mM sodium hydroxide, to promote the formation of 3 MX clusters with Na and to enable the detection of higher ordered clustered 3 MX structures. 3 MX solutions were analysed by FAIMS using an Agilent 6230 TOF MS (Agilent Technologies) with a Jet Stream ESI source, combined with a prototype miniaturised chip based FAIMS device (Owlstone Ltd. Cambridge) located in front of the mass spectrometer inlet capillary (Fig. 2) The FAIMS device consists of multiple planar electrode channels each with a 100 um gap and an electrode length of 700 um. The TOF MS experimental conditions in positive ion mode were: drying gas: 8 L/min at 150 degC; sheath gas: 10 L/min at 200 degC; nebuliser gas: 30 psig; capillary voltage: 3.5 kV; nozzle voltage: 2 kV; fragmentor voltage: 150 250 V; and a sample flow rate of 10 uL/min using a syringe pump. The optimum FAIMS conditions for the selective transmission of the different 3 MX clusters, singly, doubly and multiply charged species, were determined by conducting a compensation field (CF) sweep from 2 to 5 Td at a rate of 0.5 Td/sec, for dispersion fields (DF) in the range 194 to 323 Td. Conclusions Hyphenation of FAIMS MS and IM MS has been used for the analysis of 3 MX complexes. This preliminary study into the structural analysis of 3 MX complexes shows a complexity of non covalently clustered structures. FAIMS selection has been used for the separation of overlapping charge states of 3 MX complexes. Increased S:N ratio is observed for higher order 3 MX complexes using FAIMS MS. 3 MX singly charged complexes formed in the presence of sodium show different CF values
author_names: Kayleigh L Arthur

James C Reynolds

Colin S Creaser
title: An investigation of 3 methylxanthine supramolecular complexes using field asymmetric waveform and drift tube ion mobility spectrometry combined with mass spectrometry
year: 2013

abstract: The luminescence of ptype GaP(Zn,O) a semiconducting mater ial for light emit t ing diodes, is controlled by the transit ions of the excited free electrons and by those of the electrons bound to the luminescent neares t neighbor (ZncaOp) complexes. The results of the determinat ion of the in terna l quan tum efficiency ~l) on a large number of samples, prepared by solution growth and by liquid phase epitaxy and covering a zinc concentrat ion range of 1027 5 9 10 is cm lead to the conclusion that an Auger effect acting on the bound electrons is the dominant cause of the reduction of the in ternal efficiency of the samples with a free hole concentrat ion (p) above 4 9 1017 cm where also the t rapping by "killers" becomes negligible. The Auger constant was derived, being 3 9 10 11 cm 3 sec 1. Below this concentrat ion the thermalizat ion of the electrons bound to the complexes is the more impor tant effect enhancing the otherwise relat ively small action of the killers. The best value for is ~40% at p ~5 9 1017 cm Decay time measurements, using pulsed and s ine wave modulated excitation, provide insight in the effect of screening by free holes on the radiative and Auger transit ions by using in the interpretat ion of the data the quant i ty (m/T) which is proportional to the effective radiat ive recombinat ion rate including the effect of screening ment ioned) Both radiative and Auger t ransi t ion probabilit ies are reduced by a common screening factor as low as 0.2. Electron diffusion length measurements on the epitaxial samples show a strong decrease of the minor i ty carrier l ifetime with increasing zinc concentrat ion which is ascribed main ly to the t rapping by the (ZnO) complexes whose concentrat ion increases with the zinc dolce. This study also provides information on the oxygen incorporation dur ing the crystal growth. This incorporation probably takes place at thermal equi l ibr ium between the oxygen source and the solid GaP. [O] increases with [Zn] reaching ~10 is cm 3 at [Zn] 5 10 is cm Semiconductor diodes that emit visible l ight are of increasing importance for certain applications, i.e. for indication and for display of symbols. The luminescence efficiency of such diodes is general ly much below 100% Various causes exist for this circumstance part of which are peculiar to the semiconductor material used and to the devices made from them. These causes are still a mat ter oi conjecture. In this respect the subject of this paper, ptype gal l ium phosphide doped with zinc and oxygen, is no exception. Par t ly these causes arise from the properties of the l ight emit t ing layer, i.e. ptype GaP(Zn, O) Another cause, general ly of minor importance for this type of material, is the l imited efficiency of inject ion of electrons into this layer. A study of dopant dependent recombinat ion in ptype GaP(Zn, O) is useful to elucidate the relevant properties of this layer with respect to both bulk efficiency and inject ion efficiency. With regard to the bulk efficiency results have been published by Dishman, DiDomenico, and Caruso (1) and Jayson, Bhargava, and Dixon (2) They used the dopant dependence of two observables, quan tum efficiency and decay time. In Ref. (1) it was tr ied to determine the in terna l quan tum efficiency, a difficult exper imental problem, while Ref. (2) emphasized the decay measurements. In view of the large number of model parameters a priori statements on some of these parameters were used, par t ly based on a theoretical s tudy by Sinha and DiDomenico (3) References (1) and (2) essentially used a recombinat ion model for which Fig. 1 shows a simplified level and t ransi t ion diagram. It is seen that the losses arise from two groups of nonradia t ive transit ions labeled 'nk and rn which act on the free and bound electrons, respectively, and which paral lel the transit ions rnt and rr that
author_names: J A W van der Does de Bye
title: Dependence of Recombination in p Type GaP Zn O on Dopant Concentrations
year: 1976

abstract: We report point contact spectroscopy measurements on YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta] thin films and textured bulk ceramics. The I(V) curves measured along the copper oxygen ab plane direction are characteristic of the Andreev reflection phenomenon, with a sharp break at the gap edge. This allows a rather precise determination of the (in plane) gap, [Delta] 20 meV. Subgap structure suggests the existence of a smaller gap for some orientations in the ab plane, of the order of 12 meV. The ratio of the zero bias conductance to the normal state one, in the ab direction measurements, enabled us to set a lower bound to the Fermi velocity in YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta] in this direction: v[sub F][ge]7 x 10[sup 7] cm/sec. The value of v[sub F] has a crucial importance in the determination of the theoretical explanation for superconductivity in the high temperature superconductors. For out of plane measurements, only a weak zero bias anomaly is observed at energies up to 5 meV. 18 refs. 4 figs.
author_names: Nir Hass

Guy Deutscher

Danielle Ilzycer

Gilbert Desgardin

Isabelle Monot

Meir Weger
title: Sharp gap edge and determination of the Fermi velocity in Y[sub 1]Ba[sub 2]Cu[sub 3]O[sub 7[minus][delta] by point contact spectroscopy
year: 1992