3,476 research outputs found

    Multi-Gigabit Wireless data transfer at 60 GHz

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    In this paper we describe the status of the first prototype of the 60 GHz wireless Multi-gigabit data transfer topology currently under development at University of Heidelberg using IBM 130 nm SiGe HBT BiCMOS technology. The 60 GHz band is very suitable for high data rate and short distance applications as for example needed in the HEP experments. The wireless transceiver consist of a transmitter and a receiver. The transmitter includes an On-Off Keying (OOK) modulator, an Local Oscillator (LO), a Power Amplifier (PA) and a BandPass Filter (BPF). The receiver part is composed of a BandPass- Filter (BPF), a Low Noise Amplifier (LNA), a double balanced down-convert Gilbert mixer, a Local Oscillator (LO), then a BPF to remove the mixer introduced noise, an Intermediate Amplifier (IF), an On-Off Keying demodulator and a limiting amplifier. The first prototype would be able to handle a data-rate of about 3.5 Gbps over a link distance of 1 m. The first simulations of the LNA show that a Noise Figure (NF) of 5 dB, a power gain of 21 dB at 60 GHz with a 3 dB bandwidth of more than 20 GHz with a power consumption 11 mW are achieved. Simulations of the PA show an output referred compression point P1dB of 19.7 dB at 60 GHz.Comment: Proceedings of the WIT201

    Irradiation study of a fully monolithic HV-CMOS pixel sensor design in AMS 180 nm

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    High-Voltage Monolithic Active Pixel Sensors (HV-MAPS) based on the 180 nm HV-CMOS process have been proposed to realize thin, fast and highly integrated pixel sensors. The MuPix7 prototype, fabricated in the commercial AMS H18 process, features a fully integrated on-chip readout, i.e. hit-digitization, zero suppression and data serialization. It is the first fully monolithic HV-CMOS pixel sensor that has been tested for the use in high irradiation environments like HL-LHC. We present results from laboratory and test beam measurements of MuPix7 prototypes irradiated with neutrons (up to 5.0⋅1015 neq/cm25.0\cdot10^{15}{\,\rm{n}_{\rm{eq}}/cm^2}) and protons (up to 7.8⋅1015 protons/cm27.8\cdot 10^{15} \,\rm{protons}/cm^2) and compare the performance with non-irradiated sensors. Efficiencies well above 90 % at noise rates below 200 Hz per pixel are measured. A time resolution better than 22 ns is measured for all tested settings and sensors, even at the highest irradiation fluences. The data transmission at 1.25 Gbit/s and the on-chip PLL remain fully functional

    Synthetic Studies toward Aziridinomitosenes and 9-Oxo-pyrrolo[1,2-a]indole Mitosanes Related to the Mitomycin and FR Heterocycles.

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    The aminobenzoquinone mitomycins and the dihydrobenzoxazine FR compounds are potent antitumor antibiotics. Despite structural differences, the compounds are reductively activated to analogous reactive metabolites known as leucoaziridinomitosenes. Leucoaziridinomitosenes contain two electrophilic sites at the C(1) and C(10) positions which are selectively attacked by two guanosines on complementary strands of DNA, thereby resulting in cross-link formation and cell death. Much has been learned about the complex mechanism of action of these compounds, but a better understanding of their mechanisms of action and biological origins is required in order to produce more potent and less cytotoxic synthetic analogs. The leucoaziridinomitosene derived from the semisynthetic derivative FK317 was targeted for total syntheses. The tetracyclic core of the target was accessed via intramolecular Michael addition of a chiral lithioaziridine into a vinylogous amide. Temporary protection of a stabilizing formyl group, reduction of an enoate, and subsequent transformation of the resulting alcohol provides the free C(10) carbamate. The C(10) carbamate of the intact leucoaziridinomitosene proved to be extremely labile as it was lost under acidic, basic, and neutral conditions which were explored to remove the final aziridine protecting group. Surprisingly, in contrast to the mitomycin leucoaziridinomitosenes, C(10) heterolysis of the FR leucoaziridinomitosenes was more facile than C(1) heterolysis. Nonetheless, a fully functionalized leucoaziridinomitosene derivative of FK317 was obtained. In order to probe the related biosynthetic pathways of mitomcyin C and FR900482, a mitosane derivative that could be a common precursor of both structural families was targeted for synthesis. Multiple strategies for tetracycle construction focused on addition of a lithioaziridine into an appropriate electrophile. The successful strategy employed a palladium catalyzed coupling of a 3,6-diazabicyclo[3.1.0]hexan-2-one to a functionalized aryl triflate, followed by diastereoselective cyclization to the desired stereoisomer of the tetracycle via carbanion addition into an appended lactam. The top face of the tetracycle is blocked by the large aziridine protecting group, which should facilitate diastereoselective reductive cleavage of a C(9) leaving group from the bottom face of the tetracycle to form the required C(9) stereochemistry. These studies culminated in the successful synthesis of a fully functionalized 9-oxo-pyrrolo[1,2a]indole mitosane derivative of the mitomycins and FR compounds.Ph.D.ChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/64647/1/deetersu_1.pd

    Interferometric Observations of the Nuclear Region of Arp220 at Submillimeter Wavelengths

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    We report the first submillimeter interferometric observations of an ultraluminous infrared galaxy. We observed Arp220 in the CO J=3-2 line and 342GHz continuum with the single baseline CSO-JCMT interferometer consisting of the Caltech Submillimeter Observatory (CSO) and the James Clerk Maxwell Telescope (JCMT). Models were fit to the measured visibilities to constrain the structure of the source. The morphologies of the CO J=3-2 line and 342GHz continuum emission are similar to those seen in published maps at 230 and 110GHz. We clearly detect a binary source separated by about 1 arcsec in the east-west direction in the 342GHz continuum. The CO J=3-2 visibility amplitudes, however, indicate a more complicated structure, with evidence for a compact binary at some velocities and rather more extended structure at others. Less than 30% of the total CO J=3-2 emission is detected by the interferometer, which implies the presence of significant quantities of extended gas. We also obtained single-dish CO J=2-1, CO J=3-2 and HCN J=4-3 spectra. The HCN J=4-3 spectrum, unlike the CO spectra, is dominated by a single redshifted peak. The HCN J=4-3/CO J=3-2, HCN J=4-3/HCN J=1-0 and CO J=3-2/2-1 line ratios are larger in the redshifted (eastern) source, which suggests that the two sources may have different physical conditions. This result might be explained by the presence of an intense starburst that has begun to deplete or disperse the densest gas in the western source, while the eastern source harbors undispersed high density gas.Comment: 17 pages, 9 figures, 4 Tables. accepted by Ap

    Wafer test of the LHCb Outer Tracker TDC-Chip

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    The OTIS-TDC is the front end readout chip for the LHCb Outer Tracker. It is designed to measure drift times with a resolution better than 1 ns. As the chip will be directly mounted to its board, the test have to be performed on the wafer itself. As the testing period for 7 000 chips was only three weeks, many test routines have been implemented on a FPGA. Each chip is subjected to detailed probe testing to ensure the full functionality as well as a good performance. Overall 47 wafer have been tested. From the chips passing the test 2 000 have been used in the Outer Tracker front end electronic

    The MuPix Telescope: A Thin, high Rate Tracking Telescope

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    The MuPix Telescope is a particle tracking telescope, optimized for tracking low momentum particles and high rates. It is based on the novel High-Voltage Monolithic Active Pixel Sensors (HV-MAPS), designed for the Mu3e tracking detector. The telescope represents a first application of the HV-MAPS technology and also serves as test bed of the Mu3e readout chain. The telescope consists of up to eight layers of the newest prototypes, the MuPix7 sensors, which send data self-triggered via fast serial links to FPGAs, where the data is time-ordered and sent to the PC. A particle hit rate of 1 MHz per layer could be processed. Online tracking is performed with a subset of the incoming data. The general concept of the telescope, chip architecture, readout concept and online reconstruction are described. The performance of the sensor and of the telescope during test beam measurements are presented.Comment: Proceedings TWEPP 2016, 8 pages, 7 figure

    MuPix7 - A fast monolithic HV-CMOS pixel chip for Mu3e

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    The MuPix7 chip is a monolithic HV-CMOS pixel chip, thinned down to 50 \mu m. It provides continuous self-triggered, non-shuttered readout at rates up to 30 Mhits/chip of 3x3 mm^2 active area and a pixel size of 103x80 \mu m^2. The hit efficiency depends on the chosen working point. Settings with a power consumption of 300 mW/cm^2 allow for a hit efficiency >99.5%. A time resolution of 14.2 ns (Gaussian sigma) is achieved. Latest results from 2016 test beam campaigns are shown.Comment: Proceedingsfor the PIXEL2016 conference, submitted to JINST A dangling reference has been removed from this version, no other change

    SMA CO(J=6-5) and 435 micron interferometric imaging of the nuclear region of Arp 220

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    We have used the Submillimeter Array (SMA) to make the first interferometric observations (beam size ~1") of the 12CO J=6-5 line and 435 micron (690 GHz) continuum emission toward the central region of the nearby ULIRG Arp 220. These observations resolve the eastern and western nuclei from each other, in both the molecular line and dust continuum emission. At 435 micron, the peak intensity of the western nucleus is stronger than the eastern nucleus, and the difference in peak intensities is less than at longer wavelengths. Fitting a simple model to the dust emission observed between 1.3 mm and 435 micron suggests that dust emissivity power law index in the western nucleus is near unity and steeper in the eastern nucleus, about 2, and that the dust emission is optically thick at the shorter wavelength. Comparison with single dish measurements indicate that the interferometer observations are missing ~60% of the dust emission, most likely from a spatially extended component to which these observations are not sensitive. The 12CO J=6-5 line observations clearly resolve kinematically the two nuclei. The distribution and kinematics of the 12CO J=6-5 line appear to be very similar to lower J CO lies observed at similar resolution. Analysis of multiple 12CO line intensities indicates that the molecular gas in both nuclei have similar excitation conditions, although the western nucleus is warmer and denser. The excitation conditions are similar to those found in other extreme environments, including M82, Mrk 231, and BR 1202-0725. Simultaneous lower resolution observations of the 12CO, 13CO, and C18O J=2-1 lines show that the 13CO and C18O lines have similar intensities, which suggests that both of these lines are optically thick, or possibly that extreme high mass star formation has produced in an overabundance of C18O.Comment: 13 pages (emulateapj), 10 figures, Accepted for publication in Ap

    SMA Imaging of CO(3-2) Line and 860 micron Continuum of Arp 220 : Tracing the Spatial Distribution of Luminosity

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    We used the Submillimeter Array (SMA) to image 860 micron continuum and CO(3-2) line emission in the ultraluminous merging galaxy Arp 220, achieving a resolution of 0.23" (80 pc) for the continuum and 0.33" (120 pc) for the line. The CO emission peaks around the two merger nuclei with a velocity signature of gas rotation around each nucleus, and is also detected in a kpc-size disk encompassing the binary nucleus. The dust continuum, in contrast, is mostly from the two nuclei. The beam-averaged brightness temperature of both line and continuum emission exceeds 50 K at and around the nuclei, revealing the presence of warm molecular gas and dust. The dust emission morphologically agrees with the distribution of radio supernova features in the east nucleus, as expected when a starburst heats the nucleus. In the brighter west nucleus, however, the submillimeter dust emission is more compact than the supernova distribution. The 860 micron core, after deconvolution, has a size of 50-80 pc, consistent with recent 1.3 mm observations, and a peak brightness temperature of (0.9-1.6)x10^2 K. Its bolometric luminosity is at least 2x10^{11} Lsun and could be ~10^{12} Lsun depending on source structure and 860 micron opacity, which we estimate to be of the order of tau_{860} ~ 1 (i.e., N_{H_2} ~ 10^{25} cm^{-2}). The starbursting west nuclear disk must have in its center a dust enshrouded AGN or a very young starburst equivalent to hundreds of super star clusters. Further spatial mapping of bolometric luminosity through submillimeter imaging is a promising way to identify the heavily obscured heating sources in Arp 220 and other luminous infrared galaxies.Comment: ApJ. in press. 26 pages, 10 figure

    Research Proposal for an Experiment to Search for the Decay {\mu} -> eee

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    We propose an experiment (Mu3e) to search for the lepton flavour violating decay mu+ -> e+e-e+. We aim for an ultimate sensitivity of one in 10^16 mu-decays, four orders of magnitude better than previous searches. This sensitivity is made possible by exploiting modern silicon pixel detectors providing high spatial resolution and hodoscopes using scintillating fibres and tiles providing precise timing information at high particle rates.Comment: Research proposal submitted to the Paul Scherrer Institute Research Committee for Particle Physics at the Ring Cyclotron, 104 page
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