Science.gov

Sample records for argon tpc detectors

  1. Muon-induced background to proton decay in the p →K+ ν decay channel with large underground liquid argon TPC detectors

    NASA Astrophysics Data System (ADS)

    Klinger, J.; Kudryavtsev, V. A.; Richardson, M.; Spooner, N. J. C.

    2015-06-01

    Large liquid argon TPC detector programs such as LBNE and LAGUNA-LBNO will be able to make measurements of the proton lifetime which will outperform Cherenkov detectors in the proton decay channel p →K+ ν. At the large depths which are proposed for such experiments, a non-negligible source of isolated charged kaons may be produced in the showers of cosmogenic muons. We present an estimate of the cosmogenic muon background to proton decay in the p →K+ ν channel. The simulation of muon transport to a depth of 4 km w.e. is performed in the MUSIC framework and the subsequent propagation of muons and secondary particles in the vicinity of a cylindrical 20 kt LAr target is performed using GEANT4. An exposure time of 100 years is considered, with a rate of <0.0012 events/kt/year at 90% CL predicted from our simulations.

  2. MicroBooNE, A Liquid Argon Time Projection Chamber (LArTPC) Neutrino Experiment

    SciTech Connect

    Katori, Teppei

    2011-07-01

    Liquid Argon time projection chamber (LArTPC) is a promising detector technology for future neutrino experiments. MicroBooNE is a upcoming LArTPC neutrino experiment which will be located on-axis of Booster Neutrino Beam (BNB) at Fermilab, USA. The R&D efforts on this detection method and related neutrino interaction measurements are discussed.

  3. TPB-coated light guides for liquid argon TPC light detection systems

    NASA Astrophysics Data System (ADS)

    Ignarra, C. M.

    2013-10-01

    Light detection systems in Liquid Argon Time Projection Chambers (LArTPCs) require the detection of the 128 nm light produced during argon scintillation. Most detectors use Tetraphenyl Butadiene (TPB) to shift the wavelength of the light into a range visible to Photomultiplier Tubes (PMTs). These proceedings summarize characterizations of light-guides coated with a matrix of TPB in UV transmitting acrylic which are more compact than existing LArTPC light collection systems.

  4. DarkSide-50: A WIMP Search with a Two-phase Argon TPC

    NASA Astrophysics Data System (ADS)

    Meyers, P. D.; Agnes, P.; Alton, D.; Arisaka, K.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; Brigatti, A.; Brodsky, J.; Budano, F.; Cadonati, L.; Calaprice, F.; Canci, N.; Candela, A.; Cao, H.; Cariello, M.; Cavalcante, P.; Chavarria, A.; Chepurnov, A.; Cocco, A. G.; Crippa, L.; DAngelo, D.; D'Incecco, M.; Davini, S.; De Deo, M.; Derbin, A.; Di Eusanio, F.; Di Pietro, G.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Forster, G.; Franco, D.; Gabriele, F.; Galbiati, C.; Goretti, A.; Grandi, L.; Gromov, M.; Guan, M.; Guardincerri, Y.; Hackett, B.; Herner, K.; Humble, P.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; Joliet, C.; Keeter, K.; Kendziora, C.; Kidner, S.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Kurlej, A.; Li, P.; Loer, B.; Lombardi, P.; Love, C.; Ludhova, L.; Luitz, S.; Ma, Y.; Machulin, I.; Mandarano, A.; Mari, S.; Maricic, J.; Martoff, C. J.; Meregaglia, A.; Meroni, E.; Meyers, P. D.; Milincic, R.; Montanari, D.; Montuschi, M.; Monzani, M. E.; Mosteiro, P.; Mount, B.; Muratova, V.; Musico, P.; Nelson, A.; Okounkova, M.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Papp, L.; Parmeggiano, S.; Parsells, R.; Pelczar, K.; Pelliccia, N.; Perasso, S.; Perfetto, F.; Pocar, A.; Pordes, S.; Qian, H.; Randle, K.; Ranucci, G.; Razeto, A.; Reinhold, B.; Romani, A.; Rossi, B.; Rossi, N.; Rountree, S. D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Segreto, E.; Semenov, D.; Shields, E.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Suvarov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Unzhakov, E.; Vogelaar, R. B.; Wada, M.; Wang, H.; Wang, Y.; Watson, A.; Westerdale, R.; Wojcik, M.; Wright, A.; Xu, J.; Yang, C.; Yoo, J.; Zavatarelli, S.; Zuzel, G.

    DarkSide-50 is a two phase argon TPC for direct dark matter detection which is installed at the Gran Sasso underground laboratory, Italy. DarkSide-50 has a 50-kg active volume and will make use of underground argon low in 39Ar. The TPC is installed inside an active neutron veto made with boron-loaded high radiopurity liquid scintillator. The neutron veto is installed inside a 1000 m3 water Cherenkov muon veto. The DarkSide-50 TPC and cryostat are assembled in two radon-free clean rooms to reduce radioactive contaminants. The overall design aims for a background free exposure after selection cuts are applied. The expected sensitivity for WIMP-nucleon cross section is of the order of 10-45 cm2 for WIMP masses around 100 GeV/c2. The commissioning and performance of the detector are described. Details of the low-radioactivity underground argon and other unique features of the projects are reported.

  5. Front-End ASIC for Liquid Argon TPC

    SciTech Connect

    De Geronimo, G.; Li, S.; D'Andragora, A.; Nambiar, N.; Rescia, S.; Vernon, E.; Chen, H.; Lanni, F.; Makowiecki, D.; Radeka, V.; Thorn, C.; Yu, B.

    2011-06-15

    We present a front-end application-specific integrated circuit (ASIC) for a wire based time-projection-chamber (TPC) operating in liquid Argon (LAr). The LAr TPC will be used for long baseline neutrino oscillation experiments. The ASIC must provide a low-noise readout of the signals induced on the TPC wires, digitization of those signals at 2 MSamples/s, compression, buffering and multiplexing. A resolution of better than 1000 rms electrons at 200 pF input capacitance for an input range of 300 fC is required, along with low power and operation in LAr (at 87 K). We include the characterization of a commercial technology for operation in the cryogenic environment and the first experimental results on the analog front end. The results demonstrate that complementary metal-oxide semiconductor transistors have lower noise and much improved dc characteristics at LAr temperature. Finally, we introduce the concept of '1/f equivalent' to model the low-frequency component of the noise spectral density, for use in the input metal-oxide semiconductor field-effect transistor optimization.

  6. Optical readout of a two phase liquid argon TPC using CCD camera and THGEMs

    NASA Astrophysics Data System (ADS)

    Mavrokoridis, K.; Ball, F.; Carroll, J.; Lazos, M.; McCormick, K. J.; Smith, N. A.; Touramanis, C.; Walker, J.

    2014-02-01

    This paper presents a preliminary study into the use of CCDs to image secondary scintillation light generated by THick Gas Electron Multipliers (THGEMs) in a two phase LAr TPC. A Sony ICX285AL CCD chip was mounted above a double THGEM in the gas phase of a 40 litre two-phase LAr TPC with the majority of the camera electronics positioned externally via a feedthrough. An Am-241 source was mounted on a rotatable motion feedthrough allowing the positioning of the alpha source either inside or outside of the field cage. Developed for and incorporated into the TPC design was a novel high voltage feedthrough featuring LAr insulation. Furthermore, a range of webcams were tested for operation in cryogenics as an internal detector monitoring tool. Of the range of webcams tested the Microsoft HD-3000 (model no:1456) webcam was found to be superior in terms of noise and lowest operating temperature. In ambient temperature and atmospheric pressure 1 ppm pure argon gas, the THGEM gain was ≈ 1000 and using a 1 msec exposure the CCD captured single alpha tracks. Successful operation of the CCD camera in two-phase cryogenic mode was also achieved. Using a 10 sec exposure a photograph of secondary scintillation light induced by the Am-241 source in LAr has been captured for the first time.

  7. A Large Liquid Argon TPC for Off-axis NuMI Neutrino Physics

    SciTech Connect

    Menary, Scott

    2006-07-11

    The ICARUS collaboration has shown the power of the liquid argon time projection chamber (LArTPC) technique to image events with bubble-chamber-like quality. I will describe a proposed long-baseline {nu}e appearance experiment utilizing a large ({>=} 15 kton1) LArTPC placed off-axis of Fermilab's NuMI {nu}{mu} beam. The total LArTPC program as it presently stands, which includes a number of smaller R and D projects designed to examine the key design issues, will be outlined.

  8. Integrated plan for LArTPC neutrino detectors in the US

    SciTech Connect

    Baller, B.; Fleming, B.; /Fermilab

    2009-11-01

    We present an integrated R&D plan aimed at demonstrating the ability to build a very large Liquid Argon Time Projection Chamber (LArTPC), on a scale suitable for use as a Far Detector for the LBNE neutrino oscillation experiment. This plan adopts current LArTPC R&D-related activities and proposes new ones to address questions that go beyond those being answered by the current efforts. We have employed a risk evaluation strategy to identify questions that can be answered (or risks that can be mitigated) through one or more R&D steps. In summary form, the plan consists of the following pre-existing components: (1) The Materials Test Stand program, now in operation at Fermilab, addressing questions pertaining to maintenance of argon purity; (2) Existing electronics test stands at FNAL and BNL; (3) The Liquid Argon Purity Demonstrator (LAPD) now being assembled at Fermilab; (4) The ArgoNeuT prototype LArTPC, now running in the NuMI beam; (5) The MicroBooNE experiment, proposed as a physics experiment that will advance our understanding of the LArTPC technology, now completing its conceptual design phase; (6) A software development effort that is well integrated across present and planned LArTPC detectors. We are proposing to add to these efforts the following: (1) A membrane cryostat mechanical prototype to evaluate and gain expertise with this technology; (2) An installation and integration prototype, to understand issues pertaining to detector assembly, particularly in an underground environment; (3) A {approx} 5% scale electronics systems test to understand system-wide issues as well as individual component reliability. (4) A calibration test stand that would consist of a small TPC to be exposed to a test beam for calibration studies, relevant for evaluation of physics sensitivities. We have developed a timeline and milestones for achieving these goals as discussed in Section 4. The proposed activities necessary for the final design of LAr20 are complete by CD3 in

  9. Improved TPB-coated light guides for liquid argon TPC light detection systems

    NASA Astrophysics Data System (ADS)

    Moss, Z.; Bugel, L.; Collin, G.; Conrad, J. M.; Jones, B. J. P.; Moon, J.; Toups, M.; Wongjirad, T.

    2015-08-01

    Scintillation light produced in liquid argon (LAr) must be shifted from 128 nm to visible wavelengths in light detection systems used for liquid argon time-projection chambers (LArTPCs). To date, LArTPC light collection systems have employed tetraphenyl butadiene (TPB) coatings on photomultiplier tubes (PMTs) or plates placed in front of the PMTs. Recently, a new approach using TPB-coated light guides was proposed. In this paper, we report on light guides with improved attenuation lengths above 100 cm when measured in air. This is an important step in the development of meter-scale light guides for future LArTPCs. Improvements come from using a new acrylic-based coating, diamond-polished cast UV transmitting acrylic bars, and a hand-dipping technique to coat the bars. We discuss a model for connecting bar response in air to response in liquid argon and compare this to data taken in liquid argon. The good agreement between the prediction of the model and the measured response in liquid argon demonstrates that characterization in air is sufficient for quality control of bar production. This model can be used in simulations of light guides for future experiments.

  10. Argon-39 Background in DUNE Photon Detectors

    NASA Astrophysics Data System (ADS)

    Sinev, Gleb; DUNE Collaboration

    2016-03-01

    The Deep Underground Neutrino Experiment (DUNE) is a 40-kt liquid argon detector that will be constructed 5000 ft underground in the Sanford Underground Research Facility in order to study neutrino and proton decay physics. Instrumenting liquid argon with photon detectors to record scintillation in addition to the ionization signal can significantly improve time and energy resolution of the experiment. Argon produces light with wavelength of 128 nm. The reference design for the photon detectors includes acrylic bars covered in wavelength shifter, where the scintillation light can be captured and reemitted with longer wavelengths, then detected using silicon photomultipliers. Radiological backgrounds may noticeably deteriorate the photon detection system performance, especially for low-energy interactions. A particularly important background comes from argon-39 decays, because argon-39 is present in natural argon that will be used in DUNE and the background rate increases with the size of the experiment. The effect of the argon-39 background has been studied and is presented in this talk.

  11. MicroBooNE and the Road to Large Liquid Argon Neutrino Detectors

    NASA Astrophysics Data System (ADS)

    Karagiorgi, G.

    Liquid Argon Time Projection Chambers (LArTPC's) provide a promising technology for multi-kiloton scale detectors aiming to address-among other pressing particle physics questions-the possibility of short and long baseline electron neutrino and antineutrino appearance. MicroBooNE, a 170 ton LArTPC under construction, is the next necessary step in a phased R&D effort toward construction and stable operation of larger-scale LArTPC's. This development effort also leans heavily on the ArgoNeuT and LAr1 LArTPC R&D experiments at Fermilab. In addition to advancing the LArTPC technology, these projects also provide unique physics opportunities. For example, Micro-BooNE will be located in the Booster Neutrino Beamline at Fermilab, at ∼470 m from neutrino production. Thus, in addition to measuring a suite of low energy neutrino cross sections on argon, MicroBooNE will investigate the anomalous low energy excess seen by the MiniBooNE experiment. Furthermore, the neutrino beam energy and relatively short baseline provide MicroBooNE with sensitivity to high-∼m2 neutrino oscillations. These proceedings summarize the role of the MicroBooNE detector in the US LArTPC R&D program, present its physics reach, and briefly discuss the physics potential of a dedicated near-future neutrino oscillation program at the Booster Neutrino Beamline, as a way to maximize the physics output of the Fermilab LArTPC R&D projects.

  12. WA105: a large-scale demonstrator of the Liquid Argon double phase TPC

    NASA Astrophysics Data System (ADS)

    Tonazzo, A.; WA105 Collaboration

    2016-05-01

    The physics case for a large underground detector devoted to neutrino oscillation measurements, nucleon decay and astrophysics is compelling. A time projection chamber based on the dual-phase liquid Argon technique is an extremely attractive option, allowing for long drift distances, low energy threshold and high readout granularity. It has been extensively studied in the LAGUNA-LBNO Design Study and is one of the two designs foreseen for the modules of the DUNE detector in the US. The WA105 experiment envisages the construction of a large scale prototype at CERN, to validate technical solutions and perform physics studies with charged particle beams.

  13. Photon Detection System for LBNE Liquid Argon Detector

    NASA Astrophysics Data System (ADS)

    Djurcic, Zelimir

    2014-03-01

    The LBNE (Long-Baseline Neutrino Experiment) is the next generation accelerator-based neutrino oscillation experiment planned in US. The experiment will use a new muon-neutrino beam sent from Fermi National Accelerator Laboratory and will detect electron-neutrino appearance and muon-neutrino disappearance using a Liquid Argon TPC located at a distance of 1300 km at Sanford Underground Research Facility in South Dakota. The primary physics goal of the LBNE is a definitive determination the neutrino mass hierarchy, determination the octant of the neutrino mixing angle theta-23, and precise measurement of CP violation in neutrino oscillation. Neutrino interaction in LAr result in charged particles producing ionization and scintillation light signals. Dedicated photon detection system is under design for use in the LBNE LArTPC far detectors. The baseline design couples wavelength-shifter coated ultraviolet transmitting acrylic to 3 mm2 silicon photomultipliers. By detecting scintillation light we aim to improve event reconstruction capabilities and efficiently separate neutrino events from background. Current status of the system will be described.

  14. A TPC detector for the study of high multiplicity heavy ion collisions

    SciTech Connect

    Rai, G.; Arthur, A.; Beiser, F.; Harnden, C.W.; Jones, R.; Kleinfelder, S.; Lee, K.; Matis, H.S.; Nakamura, M.; McParland, C.; Nesbitt, D.; Odyniec, G.; Olson, D.; Pugh, H.G.; Ritter, H.G.; Symons, T.J.M.; Weiman, H.; Wright, R. ); Rudge, A. )

    1990-04-01

    The design of the time projection chamber (TPC) detector with complete pad coverage is presented. The TPC will allow the measurements of high multiplicity ({approx}200 tracks) relativistic nucleus-nucleus collisions initiated with the heaviest, most energetic projectiles available at the LBL BEVALAC accelerator facility. The front end electronics, composed of over 15,000 time sampling channels, will be located on the chamber. The highly integrated, custom designed, electronics and the VME based data acquisition system are described.

  15. A TPC (Time Projection Chamber) detector for the study of high multiplicity heavy ion collisions

    SciTech Connect

    Rai, G.; Arthur, A.; Bieser, F.; Harnden, C.W.; Jones, R.; Klienfelder, S.; Lee, K.; Matis, H.S.; Nakamura, M.; McParland, C.; Nesbitt, D.; Odyniec, G.; Olson, D.; Pugh, H.G.; Ritter, H.G.; Symons, T.J.M.; Wieman, H.; Wright, M.; Wright, R. ); Rudge, A. )

    1990-01-01

    The design of a Time Projection Chamber (TPC) detector with complete pad coverage is presented. The TPC will allow the measurements of high multiplicity ({approx} 200 tracks) relativistic nucleus-nucleus collisions initiated with the heaviest, most energetic projectiles available at the LBL BEVALAC accelerator facility. The front end electronics, composed of over 15,000 time sampling channels, will be located on the chamber. The highly integrated, custom designed, electronics and the VME based data acquisition system are described. 10 refs., 8 figs., 1 tab.

  16. The Gap-Tpc

    NASA Astrophysics Data System (ADS)

    Rossi, B.; Anastasio, A.; Boiano, A.; Catalanotti, S.; Cocco, A. G.; Covone, G.; Di Meo, P.; Longo, G.; Vanzanella, A.; Walker, S.; Wang, H.; Wang, Y.; Fiorillo, G.

    2016-02-01

    Several experiments have been conducted worldwide, with the goal of observing low-energy nuclear recoils induced by WIMPs scattering off target nuclei in ultra-sensitive, low-background detectors. In the last few decades noble liquid detectors designed to search for dark matter in the form of WIMPs have been extremely successful in improving their sensitivities and setting the best limits. One of the crucial problems to be faced for the development of large size (multi ton-scale) liquid argon experiments is the lack of reliable and low background cryogenic PMTs: their intrinsic radioactivity, cost, and borderline performance at 87 K rule them out as a possible candidate for photosensors. We propose a brand new concept of liquid argon-based detector for direct dark matter search: the Geiger-mode Avalanche Photodiode Time Projection Chamber (GAP-TPC) optimized in terms of residual radioactivity of the photosensors, energy and spatial resolution, light and charge collection efficiency.

  17. Improved TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

    NASA Astrophysics Data System (ADS)

    Moss, Zander

    2015-04-01

    This talk will discuss the outcome of recent research and development of wavelength-shifting lightguides for LArTPCs. The response of the lightguides was characterized in both air and liquid argon. Attenuation lengths over 100cm were consistently measured in air, which is an important step in the development of meter-scale lightguides for future LArTPCs. Additionally, good agreement was found between simulations and measurements performed in air and liquid argon. Such agreement indicates that characterization in air is sufficient for quality control of lightguide production. Zander Moss for the MIT Light Collection R&D Group.

  18. Performance and technical challenges of liquid argon detectors

    SciTech Connect

    Rebel, Brian; /Fermilab

    2011-01-01

    Liquid argon time projection chambers offer the possibility of incredible resolution of particle interactions. This review outlines the ongoing research and development towards the realization of a multi-kiloton scale detector. The ICARUS and ArgoNeuT experiments which make use of liquid argon time projection chamber technology are also described.

  19. New Measurement of ^39Ar in Underground Argon with a Low Background Liquid Argon Detector

    NASA Astrophysics Data System (ADS)

    Xu, Jingke

    2012-03-01

    A low background liquid argon detector has been developed for sensitive measurements of the beta radioactive ^39Ar in argon from underground sources. The measurement is motivated by the need to improve on earlier studies that showed no sign of ^39Ar in certain sources of underground argon, but with a limited sensitivity of ˜ 5% relative to ^39Ar in atmospheric argon[1]. We will report preliminary measurements taken with the low background detector that was commissioned and operated at the Kimballton Underground Research Facility (KURF) in Virginia. A combination of passive and active background reduction techniques resulted in a very low background and a null result with sensitivity to ^39Ar less than 1% of atmospheric. The results confirm that underground argon is well suited for direct detection of dark matter WIMPs. [4pt] [1] D. Acosta-Kane et al., Nucl. Instr. Meth. A 587:46 (2008)

  20. Current and future liquid argon neutrino experiments

    SciTech Connect

    Karagiorgi, Georgia S.

    2015-05-15

    The liquid argon time projection chamber (LArTPC) detector technology provides an opportunity for precision neutrino oscillation measurements, neutrino cross section measurements, and searches for rare processes, such as SuperNova neutrino detection. These proceedings review current and future LArTPC neutrino experiments. Particular focus is paid to the ICARUS, MicroBooNE, LAr1, 2-LArTPC at CERN-SPS, LBNE, and 100 kton at Okinoshima experiments.

  1. TPC Detectors for Neutrino-less Double-Beta Decay and Dark Matter Searches

    NASA Astrophysics Data System (ADS)

    Goldschmidt, Azriel

    2012-10-01

    Time Projection Chambers (TPCs) are increasingly becoming the particle detector technology of choice for rare event searches such as neutrino-less double beta decays and direct WIMP dark matter interactions. At present time, experiments using xenon-filled TPCs are producing some of the best limits for both of these searches. TPCs offer 3D ionization-track imaging as well as calorimetric energy measurements both of which are important handles for the identification of the rare sought-after events while discarding background events due to cosmic rays or due to radioactive decays in the detector or surrounding materials. Particle identification, beyond that provided by the particle range and dE/dx information, is also available from the relative amount of ionization and excitation losses and is essential for the WIMP searches. The contiguous gas or liquid volume at the heart of a TPC is continuously purified to remove contaminants that would otherwise deteriorate the detector performance or produce backgrounds. The fiducial volume for the event searches can be defined after the fact and is typically chosen to be well separated from the physical boundaries of the working gas or liquid to avoid surface events that often are problematic and much harder to reject in solid state detectors. The scalability of the TPC is one of its most important advantages in a field where ever increasing detector masses are required to achieve the required sensitivities. Detectors of O(100) kg scale are in operation and construction and ton to multi-ton detectors are being planned and expected to come on-line in the next years. In this talk I will describe the various types of TPCs in use or planned and will discuss their potential for achieving the exciting goals of discovering the dark matter particle and observing neutrino-less double beta decays.

  2. Light yield in DarkSide-10: A prototype two-phase argon TPC for dark matter searches

    NASA Astrophysics Data System (ADS)

    Alexander, T.; Alton, D.; Arisaka, K.; Back, H. O.; Beltrame, P.; Benziger, J.; Bonfini, G.; Brigatti, A.; Brodsky, J.; Cadonati, L.; Calaprice, F.; Candela, A.; Cao, H.; Cavalcante, P.; Chavarria, A.; Chepurnov, A.; Cline, D.; Cocco, A. G.; Condon, C.; D'Angelo, D.; Davini, S.; De Haas, E.; Derbin, A.; Di Pietro, G.; Dratchnev, I.; Durben, D.; Empl, A.; Etenko, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Gabriele, F.; Galbiati, C.; Gazzana, S.; Ghag, C.; Ghiano, C.; Goretti, A.; Grandi, L.; Gromov, M.; Guan, M.; Guo, C.; Guray, G.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; Kayunov, A.; Keeter, K.; Kendziora, C.; Kidner, S.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Shields, E.; Li, P.; Loer, B.; Lombardi, P.; Love, C.; Ludhova, L.; Lukyanchenko, L.; Lund, A.; Lung, K.; Ma, Y.; Machulin, I.; Maricic, J.; Martoff, C. J.; Meng, Y.; Meroni, E.; Meyers, P. D.; Mohayai, T.; Montanari, D.; Montuschi, M.; Mosteiro, P.; Mount, B.; Muratova, V.; Nelson, A.; Nemtzow, A.; Nurakhov, N.; Orsini, M.; Ortica, F.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Parsells, R.; Pelliccia, N.; Perasso, L.; Perfetto, F.; Pinsky, L.; Pocar, A.; Pordes, S.; Ranucci, G.; Razeto, A.; Romani, A.; Rossi, N.; Saggese, P.; Saldanha, R.; Salvo, C.; Sands, W.; Seigar, M.; Semenov, D.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Teymourian, A.; Thompson, J.; Unzhakov, E.; Vogelaar, R. B.; Wang, H.; Westerdale, S.; Wojcik, M.; Wright, A.; Xu, J.; Yang, C.; Zavatarelli, S.; Zehfus, M.; Zhong, W.; Zuzel, G.

    2013-09-01

    As part of the DarkSide program of direct dark matter searches using two-phase argon TPCs, a prototype detector with an active volume containing 10 kg of liquid argon, DarkSide-10, was built and operated underground in the Gran Sasso National Laboratory in Italy. A critically important parameter for such devices is the scintillation light yield, as photon statistics limits the rejection of electron-recoil backgrounds by pulse shape discrimination. We have measured the light yield of DarkSide-10 using the readily-identifiable full-absorption peaks from gamma ray sources combined with single-photoelectron calibrations using low-occupancy laser pulses. For gamma lines of energies in the range 122-1275 keV, we get light yields averaging 8.887±0.003(stat)±0.444(sys) p.e./keVee. With additional purification, the light yield measured at 511 keV increased to 9.142±0.006(stat) p.e./keVee.

  3. The Liquid Argon Calorimeter system for the SLC Large Detector

    SciTech Connect

    Haller, G.M.; Fox, J.D.; Smith, S.R.

    1988-09-01

    In this paper the physical packaging and the logical organization of the Liquid Argon Calorimeter (LAC) electronics system for the Stanford Linear Collider Large Detector (SLD) at SLAC are described. This system processes signals from approximately 44,000 calorimeter towers and is unusual in that most electronic functions are packaged within the detector itself as opposed to an external electronics support rack. The signal path from the towers in the liquid argon through the vacuum to the outside of the detector is explained. The organization of the control logic, analog electronics, power regulation, analog-to-digital conversion circuits, and fiber optic drivers mounted directly on the detector are described. Redundancy considerations for the electronics and cooling issues are discussed. 12 refs., 5 figs.

  4. Liquid-Argon Time Projection Chambers in the U.S

    SciTech Connect

    Soderberg, M.

    2009-10-01

    Liquid Argon Time Projection Chamber (LAr TPC) detectors are ideally suited for studying neutrino interactions and probing the parameters that characterize neutrino oscillations. The ability to drift ionization particles over long distances in purified argon and to trigger on abundant scintillation light allows for excellent particle identification and triggering capability. Recent U.S. based work in the development of LAr TPC technology for massive kiloton size detectors will be discussed in this talk, including details of the ArgoNeuT (Argon Neutrino Test) test-beam project, which is a 175 liter LAr TPC exposed to Fermilab's NuMI neutrino beamline.

  5. TPC-like readout for thermal neutron detection using a GEM-detector

    NASA Astrophysics Data System (ADS)

    Flierl, B.; Hertenberger, R.; Biebel, O.; Zeitelhack, K.

    2016-07-01

    Spatial resolution of less than 200 μm is challenging for thermal neutron detection. A novel readout scheme based on the time-projection-chamber (TPC) concept is used in a gaseous electron multiplier (GEM) detector [1]. Thermal neutrons are captured in a single 2 μm thick Boron-10 converter cathode and secondary Helium and Lithium ions are produced with a combined energy of 2.8 MeV. These ions have sufficient energy to form straight tracks of several mm length. With a time resolving 2-dimensional readout of 400 μm pitch in both directions, based on APV25 chips, the ions are tracked and their respective origin in the cathode converter foil is reconstructed. Using an Ar-CO2 93:7% gas mixture, a resolution of 100 μm (FWHM 235 μm) has been observed with a triple GEM-detector setup at the Garching neutron source (FRMII) for neutrons of 4.7 Å.

  6. A 3-D image chamber for the liquid argon TPC based on multi-layer printed circuit board

    NASA Astrophysics Data System (ADS)

    Cennini, P.; Cittolin, S.; Revol, J. P.; Rubbia, C.; Tian, W. H.; Li, X.; Picchi, P.; Cavanna, F.; Piano Mortari, G.; Verdecchia, M.; Cline, D.; Liu, Y.; Muratori, G.; Otwinowski, S.; Wang, H.; Zhou, M.; Bettini, A.; Casagrande, F.; Centro, S.; De Vecchi, C.; Pepato, A.; Pietropaolo, F.; Rossi, P.; Ventura, S.; Benetti, P.; Calligarich, E.; Dolfini, R.; Gigli Berzolari, A.; Mauri, F.; Montanari, C.; Piazzoli, A.; Rappoldi, A.; Raselli, U. L.; Scannicchio, D.; Periale, L.; Suzuki, S.

    1994-08-01

    In our research and development programme for the ICARUS experiment we have developed a novel three-dimensional readout scheme for a liquefied noble gas TPC, where no charge multiplication process takes place. The design avoids completely wire grids and is based on the multilayer circuit technique. As a consequence it is intrinsically safe and suited to be used in large and modular structures as those foreseen for ICARUS. We describe here how the electrodes structure can be simplified leading to the new design principles and we present the results obtained with a small prototype chamber in a 100 GeV μ beam.

  7. Development of membrane cryostats for large liquid argon neutrino detectors

    NASA Astrophysics Data System (ADS)

    Montanari, D.; Bremer, J.; Gendotti, A.; Geynisman, M.; Hentschel, S.; Loew, T.; Mladenov, D.; Montanari, C.; Murphy, S.; Nessi, M.; Norris, B.; Noto, F.; Rubbia, A.; Sharma, R.; Smargianaki, D.; Stewart, J.; Vignoli, C.; Wilson, P.; Wu, S.

    2015-12-01

    A new collaboration is being formed to develop a multi-kiloton Long-Baseline neutrino experiment that will be located at the Surf Underground Research Facility (SURF) in Lead, SD. In the present design, the detector will be located inside cryostats filled with 68,400 ton of ultrapure liquid argon (less than 100 parts per trillion of oxygen equivalent contamination). To qualify the membrane technology for future very large-scale and underground implementations, a strong prototyping effort is ongoing: several smaller detectors of growing size with associated cryostats and cryogenic systems will be designed and built at Fermilab and CERN. They will take physics data and test different detector elements, filtration systems, design options and installation procedures. In addition, a 35 ton prototype is already operational at Fermilab and will take data with single-phase detector in early 2016. After the prototyping phase, the multi-kton detector will be constructed. After commissioning, it will detect and study neutrinos from a new beam from Fermilab. These cryostats will be engineered, constructed, commissioned, and qualified by an international engineering team. This contribution presents the on-going effort on the development of the cryostats and details the requirements and the current status of the design.

  8. Development of cryogenic installations for large liquid argon neutrino detectors

    NASA Astrophysics Data System (ADS)

    Adamowski, M.; Bremer, J.; Geynisman, M.; Hentschel, S.; Montanari, D.; Nessi, M.; Norris, B.

    2015-12-01

    A proposal for a very large liquid argon (68,000 kg) based neutrino detector is being studied. To validate the design principles and the detector technology, and to gain experience in the development of the cryostats and the cryogenic systems needed for such large experiments, several smaller scale installations will be developed and implemented, at Fermilab and CERN. The cryogenic systems for these installations will be developed, constructed, installed and commissioned by an international engineering team. These installations shall bring the required cooling power under specific conditions to the experiments for the initial cool-down and the long term operation, and shall also guarantee the correct distribution of the cooling power within the cryostats to ensure a homogeneous temperature distribution within the cryostat itself. The cryogenic systems shall also include gaseous and liquid phase argon purification devices to be used to reach and maintain the very stringent purity requirements needed for these installations (parts per trillion of oxygen equivalent contamination). This paper gives an overview of the installations involved in these cryogenic projects, describes the functional demands made to these cryogenic systems and presents the initial studies on which these future cryogenic systems will be based.

  9. First tests of a Micromegas TPC in a magnetic field

    SciTech Connect

    Colas, P.; Giomataris, I.; Lepeltier, V.; Ronan, M.

    2004-12-10

    Since the summer of 2003, a large Micromegas TPC prototype (1000 channels, 50 cm drift, 50 cm diameter) has been operated in a 2T superconducting magnet at Saclay. A description of this apparatus and first results from cosmic ray tests are presented. Additional measurements using simpler detectors with a laser source, an X-ray gun and radio-active sources are discussed. Drift velocity and gain measurements, electron attachment and aging studies for a Micromegas TPC are presented. In particular, using simulations and measurements, it is shown that an $Argon-CF_4$ mixture is optimal for operation at a future Linear Collider.

  10. Liquid argon Time Projection Chamber

    SciTech Connect

    Doe, P.J.; Mahler, H.J.; Chen, H.H.

    1984-01-01

    The principal features of the liquid argon TPC are outlined and the status of development efforts, particularly at UCI, are discussed. Technical problems associated with liquid TPC's are: the liquid must be maintained at a high level of purity to enable long distance drifting of ionization electrons, and the signal size is small due to the absence of practical charge multiplication as found in gas chambers. These problems have been largely resolved in studies using small (1 to 100 l) detectors, thus allowing a realistic consideration of the physics potential of such devices.

  11. Study of pion photo-production using a TPC detector to determine beam asymmetries from polarized HD

    NASA Astrophysics Data System (ADS)

    Kizilgul, Serdar A.

    The Laser Electron Gamma Source facility (LEGS) provides intense, polarized, tagged gamma-ray beams by Compton backscattering laser light from relativistic electrons circulating in the X-Ray storage ring of the NSLS at BNL, Upton, NY. A series of double-polarization experiments (beam and target) has been completed to study the helicity structure of the nucleon. Neutral-pion measurements were completed in 2005 by using the Spin ASYmmetry detector system (SASY) which covers a large solid angle and allows for detection of a large range of neutral pions. Charged-pion experiments were completed in 2006. This new experiment yields data on the beam asymmetry Sigma for a polarized Hydrogen Deuterium (HD) target from the 2006 data. A Time Projection Chamber (TPC), surrounded by two-Tesla magnet, was built and incorporated into SASY to identify the pion charge and so separate neutron and proton reactions. The TPC provides snap-shots of ionizing tracks of particles produced by 300-422 MeV polarized photons on a polarized HD target. A polarized HD target was developed and used in these experiments.

  12. Extreme argon purity in a large, non-evacuated cryostat

    SciTech Connect

    Tope, Terry; Adamowski, Mark; Carls, B.; Hahn, A.; Jaskierny, W.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Skup, E.; Stancari, M.; Yang, T.

    2014-01-29

    Liquid Argon Time Projection Chambers (LArTPCs) show promise as scalable devices for the large detectors needed for long-baseline neutrino oscillation physics. Over the last several years at Fermilab a staged approach to developing the technology for large detectors has been developed. The TPC detectors require ultra-pure liquid argon with respect to electronegative contaminants such as oxygen and water. The tolerable electronegative contamination level may be as pure as 60 parts per trillion of oxygen. Three liquid argon cryostats operated at Fermilab have achieved the extreme purity required by TPCs. These three cryostats used evacuation to remove atmospheric contaminants as the first purification step prior to filling with liquid argon. Future physics experiments may require very large detectors with tens of kilotonnes of liquid argon mass. The capability to evacuate such large cryostats adds significant cost to the cryostat itself in addition to the cost of a large scale vacuum pumping system. This paper describes a 30 ton liquid argon cryostat at Fermilab which uses purging to remove atmospheric contaminants instead of evacuation as the first purification step. This cryostat has achieved electronegative contamination levels better than 60 parts per trillion of oxygen equivalent. The results of this liquid argon purity demonstration will strongly influence the design of future TPC cryostats.

  13. Pad TPC

    SciTech Connect

    Hilke, H.J.

    1984-01-01

    A new kind of TPC is described, in which no sense wires exist but gas amplification is obtained from a single parallel gap. A mesh separates the drift volume from the amplifying gap. The anode is segmented into circular rows of narrow pads for rphi measurement by centroid finding and into wide circular pads for dE/dx sampling. The expected advantages of this technique are: better, track angle independent rphi resolution (no need for wire pulse height corrections); better two-track separation if more electronic channels can be afforded; less dead space from frame structures; reduced positive feedback and slower chamber deterioration by deposit formation on the anode. Very tight construction tolerances are the principle drawback. The properties of the Pad TPC are discussed in view of large scale construction and first test results are presented.

  14. Photodegradation mechanisms of tetraphenyl butadiene coatings for liquid argon detectors

    NASA Astrophysics Data System (ADS)

    Jones, B. J. P.; VanGemert, J. K.; Conrad, J. M.; Pla-Dalmau, A.

    2013-01-01

    We report on studies of degradation mechanisms of tetraphenyl butadiene (TPB) coatings of the type used in neutrino and dark matter liquid argon experiments. Using gas chromatography coupled to mass spectrometry we have detected the ultraviolet-blocking impurity benzophenone. We monitored the drop in performance and increase of benzophenone concentration in TPB plates with exposure to ultraviolet (UV) light, and demonstrate the correlation between these two variables. Based on the presence and initially exponential increase in the concentration of benzophenone observed, we propose that TPB degradation is a free radical-mediated photooxidation reaction, which is subsequently confirmed by displaying delayed degradation using a free radical inhibitor. Finally we show that the performance of wavelength-shifting coatings of the type envisioned for the LBNE experiment can be improved by 10-20%, with significantly delayed UV degradation, by using a 20% admixture of 4-tert-Butylcatechol.

  15. Expected performance of an ideal liquid argon neutrino detector with enhanced sensitivity to scintillation light

    NASA Astrophysics Data System (ADS)

    Sorel, M.

    2014-10-01

    Scintillation light is used in liquid argon (LAr) neutrino detectors to provide a trigger signal, veto information against cosmic rays, and absolute event timing. In this work, we discuss additional opportunities offered by detectors with enhanced sensitivity to scintillation light, that is with light collection efficiencies of about 10-3. We focus on two key detector performance indicators for neutrino oscillation physics: calorimetric neutrino energy reconstruction and neutrino/antineutrino separation in a non-magnetized detector. Our results are based on detailed simulations, with neutrino interactions modelled according to the GENIE event generator, while the charge and light responses of a large LAr ideal detector are described by the Geant4 and NEST simulation tools. A neutrino energy resolution as good as 3.3% RMS for 4 GeV electron neutrino charged-current interactions can in principle be obtained in a large detector of this type, by using both charge and light information. By exploiting muon capture in argon and scintillation light information to veto muon decay electrons, we also obtain muon neutrino identification efficiencies of about 50%, and muon antineutrino misidentification rates at the few percent level, for few-GeV neutrino interactions that are fully contained. We argue that the construction of large LAr detectors with sufficiently high light collection efficiencies is in principle possible.

  16. A prototype of a directional detector for non-baryonic dark matter search: MIMAC (Micro-TPC Matrix of Chambers)

    NASA Astrophysics Data System (ADS)

    Grignon, C.; Bernard, G.; Billard, J.; Bosson, G.; Bourrion, O.; Guillaudin, O.; Koumeir, C.; Mayet, F.; Santos, D.; Colas, P.; Ferrer, E.; Giomataris, I.; Allaoua, A.; Lebreton, L.

    2009-11-01

    We have developed a micro-tpc using a pixelized bulk micromegas coupled to dedicated acquisition electronics as a read-out allowing to reconstruct the three dimensional track of a few keV recoils. The prototype has been tested with the Amande facility at the IRSN-Cadarache providing monochromatic neutrons. The first results concerning discrimination of a few keV electrons and proton recoils are presented.

  17. Radon backgrounds in the DEAP-1 liquid-argon-based Dark Matter detector

    NASA Astrophysics Data System (ADS)

    Amaudruz, P.-A.; Batygov, M.; Beltran, B.; Boudjemline, K.; Boulay, M. G.; Cai, B.; Caldwell, T.; Chen, M.; Chouinard, R.; Cleveland, B. T.; Contreras, D.; Dering, K.; Duncan, F.; Ford, R.; Gagnon, R.; Giuliani, F.; Gold, M.; Golovko, V. V.; Gorel, P.; Graham, K.; Grant, D. R.; Hakobyan, R.; Hallin, A. L.; Harvey, P.; Hearns, C.; Jillings, C. J.; Kuźniak, M.; Lawson, I.; Li, O.; Lidgard, J.; Liimatainen, P.; Lippincott, W. H.; Mathew, R.; McDonald, A. B.; McElroy, T.; McFarlane, K.; McKinsey, D.; Muir, A.; Nantais, C.; Nicolics, K.; Nikkel, J.; Noble, T.; O'Dwyer, E.; Olsen, K. S.; Ouellet, C.; Pasuthip, P.; Pollmann, T.; Rau, W.; Retiere, F.; Ronquest, M.; Skensved, P.; Sonley, T.; Tang, J.; Vázquez-Jáuregui, E.; Veloce, L.; Ward, M.

    2015-03-01

    The DEAP-1 7 kg single phase liquid argon scintillation detector was operated underground at SNOLAB in order to test the techniques and measure the backgrounds inherent to single phase detection, in support of the DEAP-3600 Dark Matter detector. Backgrounds in DEAP are controlled through material selection, construction techniques, pulse shape discrimination, and event reconstruction. This report details the analysis of background events observed in three iterations of the DEAP-1 detector, and the measures taken to reduce them. The 222 Rn decay rate in the liquid argon was measured to be between 16 and 26 μBq kg-1. We found that the background spectrum near the region of interest for Dark Matter detection in the DEAP-1 detector can be described considering events from three sources: radon daughters decaying on the surface of the active volume, the expected rate of electromagnetic events misidentified as nuclear recoils due to inefficiencies in the pulse shape discrimination, and leakage of events from outside the fiducial volume due to imperfect position reconstruction. These backgrounds statistically account for all observed events, and they will be strongly reduced in the DEAP-3600 detector due to its higher light yield and simpler geometry.

  18. Resolving the mass hierarchy with atmospheric neutrinos using a liquid argon detector

    SciTech Connect

    Gandhi, Raj; Ghoshal, Pomita; Goswami, Srubabati; Sankar, S. Uma

    2008-10-01

    We explore the potential offered by large-mass liquid argon detectors for determination of the sign of {delta}m{sub 31}{sup 2}, or the neutrino mass hierarchy, through interactions of atmospheric neutrinos. We give results for a 100 kT sized magnetized detector which provides separate sensitivity to {nu}{sub {mu}}, {nu}{sub {mu}} and, over a limited energy range, to {nu}{sub e}, {nu}{sub e}. We also discuss the sensitivity for the unmagnetized version of such a detector. After including the effect of smearing in neutrino energy and direction and incorporating the relevant statistical, theoretical, and systematic errors, we perform a binned {chi}{sup 2} analysis of simulated data. The {chi}{sup 2} is marginalized over the presently allowed ranges of neutrino parameters and determined as a function of {theta}{sub 13}. We find that such a detector offers superior capabilities for hierarchy resolution, allowing a >4{sigma} determination for a 100 kT detector over a 10-year running period for values of sin{sup 2}2{theta}{sub 13}{>=}0.05. For an unmagnetized detector, a 2.5{sigma} hierarchy sensitivity is possible for sin{sup 2}2{theta}{sub 13}=0.04.

  19. A cryogenic monitor system for the Liquid Argon Calorimeter in the SLD detector

    SciTech Connect

    Fox, M.J.; Fox, J.D.

    1988-10-01

    This paper describes the monitoring electronics system design for the Liquid Argon Calorimeter (LAC) portion of the SLD detector. This system measures temperatures and liquid levels inside the LAC cryostat and transfers the results over a fiber-optic serial link to an external monitoring computer. System requirements, unique design constraints, and detailed analog, digital and software designs are presented. Fault tolerance and the requirement for a single design to work in several different operating environments are discussed. 4 refs., 3 figs., 1 tab.

  20. GLADE Global Liquid Argon Detector Experiment: a letter of intent to FNAL

    SciTech Connect

    Thomas, Jennifer

    2012-05-13

    The recent measurements of the {theta}{sub 13} mixing angle, which controls the observable size of any CP violation effects, open a window of opportunity to take advantage of the world's most powerful existing neutrino beam together with recent successes in development of the ultimate detector technology for the detection of electron neutrinos : a liquid argon (LAr) time projection chamber. During this proposed project a 5kt LAr detector (GLADE) will be developed by European groups to be put in a cryostat in the NuMI neutrino beam at Fermi National Accelerator Laboratory in the US and will start taking data in 3-5 years time to address the neutrino mass ordering. The successful fruition of this project, along with nominal exposure at NO{nu}A and T2K, together with information from double beta decay experiments could ascertain that neutrinos are Dirac particles in the next decade.

  1. The Development of a 2000L Liquid Argon Time Projection Chamber and its Application to the Search for Proton Decay

    NASA Astrophysics Data System (ADS)

    Zhou, Ming

    A new type of particle detector, the liquid argon time projection chamber, is developed and systematically tested using cosmic ray muons with a three ton prototype. The main technical problems, such as the liquid argon purity, wire chamber configuration, low noise electronics, and their long term stability, are solved after two years of run. Most of the basic parameters associated with the liquid argon TPC technology, the charge drift velocity, the spatial resolution, charge recombination and diffusion, are extracted. In order to apply this technique to solar neutrino physics, a measurement of the intrinsive radioactive Ar^{42} was performed and the results are compatible with current limits. An application to the search for proton decay with the liquid argon TPC technique is studied and some preliminary results are reported.

  2. Development of an anti-Compton veto for HPGe detectors operated in liquid argon using silicon photo-multipliers

    NASA Astrophysics Data System (ADS)

    Janicskó Csáthy, J.; Aghaei Khozani, H.; Caldwell, A.; Liu, X.; Majorovits, B.

    2011-10-01

    A proof of concept detector is presented for scintillation light detection in liquid argon using silicon photo-multipliers. The aim of the work is to build an anti-Compton veto for germanium detectors operated directly in liquid argon as in the GERDA experiment. Wavelength shifting fibers are used to collect the scintillation light and to guide it to Multi-Pixel Photon Counters (MPPC). Sufficient light yield was achieved to realize an effective anti-Compton veto. Properties of the MPPC were studied at cryogenic temperatures and are additionally reported.

  3. Design of single phase liquid argon detectors for dark matter searches

    NASA Astrophysics Data System (ADS)

    Gastler, Daniel E.

    2012-05-01

    Within our current understanding of the makeup of the universe, dark matter makes up 25% of the total energy and over 80% of the matter in the universe. Little is known about the makeup of dark matter, but its existence has been indirectly measured using the rotation curves of galaxies, clusters of galaxies, and the Cosmic Microwave Background. To gain a greater understanding of this component of the universe, direct detection of dark matter is a major objective in particle astrophysics. One popular candidate for dark matter is the weakly interacting massive particle, or WIMP. The allowed rate of interaction between a WIMP and normal matter is extremely low, requiring new detection technologies with greater sensitivity to be explored. Though several experiments have already been conducted, no direct detection experiment has unambiguously identified a dark matter signal. This work explores the use of noble liquids, in a single liquid phase design, to detect single scatters of dark matter particles. The goal of current experiments is to investigate matter-dark-matter interaction cross-sections down to 10--45cm2. With that in mind, the MiniCLEAN detector has been designed with a 500 kg liquid argon detector volume and will be viewed by a spherical 4pi configuration of 92 photo-multiplier tubes. In order to determine the ability for single phase noble liquid to detect nuclear recoils from dark matter, several R&D experiments have been performed. These experiments undertook the measurement of how dark-matter-like nuclear recoils and background-like electronic recoils behave in liquid argon. In addition to reviewing the measurements of pulse shape discrimination and other noble liquid properties, my measurement of the scintillation efficiency is described. The scintillation efficiency characterizes the differing energy responses for nuclear and electron recoils. This was the first measurement of the scintillation efficiency in liquid argon for nuclear recoils over a wide

  4. SN-detection in LAr-TPC and the quest for (ν-Ar) cross sections

    SciTech Connect

    Cavanna, F.

    2015-05-15

    Neutrino-nucleus cross sections are of relevance to supernova astrophysics. These cross-sections can be grouped into three categories, those that affect supernova dynamics, supernova nucleosynthesis, and terrestrial supernova neutrino detection, each of which would benefit from experimental study. In this report only the relevance of an accurate knowledge of neutrino-target nucleus cross sections for SN detection will be discussed, in particular for the case of Argon, the active target material of LAr-TPC detectors currently under construction or proposed for future very massive underground experiments.

  5. Performance of the electronics for the Liquid Argon Calorimeter system of the SLC large detector

    SciTech Connect

    Vella, E.; Abt, I.; Haller, G.M.; Honma, A.

    1988-10-01

    Results of performance tests on electronics for the Liquid Argon Calorimeter (LAC) for the SLD experiment at SLAC are presented. The behavior of a sub-unit called a ''tophat,'' which processes 720 detector signals, is described. The electronics consists of charge sensitive preamplifiers, analog memories, A/D converters, and associated control and readout circuitry. An internal charge injection system is used to calibrate the overall response of the devices. Linearity is better than 1% of 0--28 pC charge at the input of the amplifiers. Noise (expressed as equivalent input charge) is less than 3000 electrons at a shaping time of 4 ..mu..s, with a slope of 2600 e/sup /minus///nF. Crosstalk to adjacent channels is less than 0.5%. The power consumption at a duty cycle of 13% is 61 W. 3 refs., 7 figs.

  6. Cold Electronics Development for the LBNE LAr TPC

    NASA Astrophysics Data System (ADS)

    Thorn, C.; De Geronimo, Gianluigi; D'Andragora, Alessio; Li, Shaorui; Nambiar, Neena; Rescia, Sergio; Vernon, Emerson; Chen, Hucheng; Lanni, Francesco; Makowiecki, Don; Radeka, Veljko; Yu, Bo

    The LBNE Project is developing a design for multiple 20 kiloton liquid argon (LAr) time projection chambers to be used as the far detector for the Long Baseline Neutrino Experiment. An essential component of this design is a complete electronic readout system designed to operate in LAr (at 90K). This system is being implemented as a CMOS ASIC, in 180 nm commercial technology, that will provide low-noise readout of the signals induced on the TPC wires, digitization of those signals at 2 MS/s, zero-suppression, buffering and output multiplexing to a small number of cryostat feed-throughs. A resolution better than 1000 rms electrons at 200 pF input capacitance for an input range of 300 fC is required, along with low power (<15mW/channel) and operation in LAr with a lifetime greater than 15 years. An analog-only frontend has been successfully completed and fully evaluated, and will be used in the MicroBooNE LAr TPC. A prototype of the digital section has been fabricated and is being evaluated. The results demonstrate that CMOS transistors have lower noise and much improved dc characteristics at LAr temperature. We will describe the progress to date and plans for the remaining development.

  7. ArgoNeuT: A Physics-Minded Liquid Argon Time Projection Chamber Test Stand

    NASA Astrophysics Data System (ADS)

    Spitz, Joshua

    2009-05-01

    ArgoNeuT is a 170 liter Liquid Argon Time Projection Chamber (LArTPC) neutrino detector set in the on-axis NuMI beamline at Fermilab. The experiment's research/design goals and physics possibilities, including a charged current quasi-elastic cross section and MA parameter measurement, are reviewed. Also, the results of the above-ground cosmic ray commissioning run with accompanying event displays and reconstructed muon tracks and the current status of the experiment are shown.

  8. Dark Sector Searches in LArTPC Experiments

    NASA Astrophysics Data System (ADS)

    Himwich, Elizabeth; MicroBooNE Collaboration

    2015-04-01

    Liquid Argon Time Projection Chamber (LArTPC) experiments, which allow for excellent event characterization and topological visualization, are sensitive to the distinct signatures of theorized low-energy dark sector phenomena. With the unique technology of LArTPC experiments, it is possible to perform a quasi-model independent dark sector search that can encompass a number of models. This talk will discuss the dark sector search in LArTPC experiments as well as the sensitivity of the MicroBooNE and Lar1-ND experiments to dark sector signatures predicted by leptophobic models, which has been evaluated based on simulated signal and background event rates.

  9. Front end electronics for the STAR TPC

    SciTech Connect

    Klein, S.R.; Barale, P.; Beuville, E.

    1995-10-01

    The Solenoidal Tracker at RHIC (STAR) is a large acceptance detector now being built to study high energy heavy ion collisions. It detects charged particles with a large time projection chamber. The 136,600 TPC pads are instrumented with waveform digitizers, implemented in custom low noise preamplifier/shaper and switched capacitor array/ADCs ICs. The system is highly integrated with all analog functions mounted on small cards that plug into the TPC. Detector mounted readout boards multiplex data from 1,152 channels onto a 1.5 Gbit/sec fiber optic link to the data acquisition system.

  10. PERFORMANCE OF THE LEAD/LIQUID ARGON SHOWER COUNTER SYSTEM OF THE MARK II DETECTOR AT SPEAR

    SciTech Connect

    Abrams, G.S.; Blocker, C.A.; Briggs, D.D.; Carithers, W.C.; Dieterle, W.E.; Eaton, M.W.; Lankford, A.J.; Pang, C.Y.; Vella, E.N.; Breidenbach, M.; Dorfan, J.M.; Hanson, G.; Hitlin, D.G.; Jenni, P.; Luth, V.

    1980-05-01

    The shower counter system of the SLAC-LBL Mark II detector is a large lead/liquid argon system of the type pioneered by Willis and Radekal; however, it differs in most details and is much larger than other such detectors currently in operation, It contains, for example, 8000 liters of liquid argon and 3000 channels of low noise electronics, which is about eight times the size of the system of Willis et al. in the CERN ISR. This paper reports, with little reference to design, on the operation and performance of the Mark II system during approximately a year and a half of operation at the Stanford Linear Accelerator Center's e{sup +}-e{sup -} facility, SPEAR. The design and construction of the system have previously been described and a detailed discussion of all aspects -- design, construction, operation, and performance -- is in preparation.

  11. On the electric breakdown in liquid argon at centimeter scale

    NASA Astrophysics Data System (ADS)

    Auger, M.; Blatter, A.; Ereditato, A.; Goeldi, D.; Janos, S.; Kreslo, I.; Luethi, M.; von Rohr, C. Rudolf; Strauss, T.; Weber, M. S.

    2016-03-01

    We present a study on the dependence of electric breakdown discharge properties on electrode geometry and the breakdown field in liquid argon near its boiling point. The measurements were performed with a spherical cathode and a planar anode at distances ranging from 0.1 mm to 10.0 mm. A detailed study of the time evolution of the breakdown volt-ampere characteristics was performed for the first time. It revealed a slow streamer development phase in the discharge. The results of a spectroscopic study of the visible light emission of the breakdowns complement the measurements. The light emission from the initial phase of the discharge is attributed to electro-luminescence of liquid argon following a current of drifting electrons. These results contribute to set benchmarks for breakdown-safe design of ionization detectors, such as Liquid Argon Time Projection Chambers (LAr TPC).

  12. Low-energy ionization yield in liquid argon for a coherent neutrino-nucleus scatter detector

    NASA Astrophysics Data System (ADS)

    Foxe, Michael P.

    ~ 4 e-- per keVr at 8 keVr. For gaseous Ar, the nuclear ionization quench factor is predicted to be ~ 0.13 at 10 keVr, which is the upper limit on this quantity obtained from the atomic collision model. In order to confidently apply the predictions of the ionization yield model, several experiments have been carried out for its validation. A single-phase Ar detector is used to both understand the processes occurring in the amplification region of a dual-phase Ar detector and to measure the nuclear ionization quench factor (ratio of the ionization signal produced in a nuclear recoil compared to that produced in an electron recoil of equal energy) in gaseous Ar. Using a portable neutron generator based on the 7Li(p,n)7 Be reaction, the nuclear ionization quench factor at 13 keVr was measured in gaseous Ar to be 0:138--0:012, which is in good agreement with the predictions of the ionization yield model. The absolute ionization yield was not measurable in gaseous Ar, because single ionization electron sensitivity has not been achieved in the single-phase Ar detector. The Gamma or Neutron Argon Recoils Resulting in Liquid Ionization (G/NARRLI) detector is a dual-phase Ar detector, which was developed to measure the ionization yield at energies below 10 keVr. While operating the G/NARRLI detector, high purity was achieved, extending the electron lifetime to ≈ 100 -- 200 micros. The ultimate sensitivity was achieved by detecting the single ionization electron peak. Detection of the single electron peak allowed absolutely calibrated spectroscopy to be performed using 55Fe to produce a 6 keV peak and 37Ar to produce a peak at 2.822 keV and a low-energy peak at 270 eV. Spectroscopic detection of the 270 eV peak represents the lowest energy measured to date in a dual-phase Ar detector. The electron yields for the 55Fe and 37Ar sources were used for the validation of the electron transport code, which was in good agreement with the modeling results. An effort was made to

  13. A FORWARD TPC FOR STAR.

    SciTech Connect

    SCHUTTAUF,A. AND THE STAR COLLABORATION

    1999-05-10

    Two Forward Time Projection Chambers (FTPC) provide charge and momentum information in the pseudorapidity range between 2.5 < |{eta}| < 4.0. A radial TPC scheme is used, where ionization electrons drift in an electric field perpendicular to the axial solenoidal magnetic field. Curved proportional wire chambers with pad readout record the track information via 19200 electronic channels. We report on measurements with various gas mixtures in a prototype chamber with and without magnetic field. The design and construction of a curved readout chamber is described. Based on the prototype measurements and the final layout of the detector the expected performance in measuring accuracy and two-track-separation is given.

  14. Development of STAR TPC for use at RHIC

    SciTech Connect

    Wieman, H.H.

    1993-10-01

    A large TPC is a main element in the STAR detector system to be used at RHIC. The TPC will provide dE/dx and tracking for the expected 4000 charged particles emitted in the pseudo rapidity window of -1 < {eta} < +1. Much of the design work has been completed on this detector and prototyping is underway. We will report on the design of this TPC and present results of prototype tests of the pad plane structure that reads out the TPC. We are investigating the use of alternative gases to improved two track resolution and momentum resolution. A new method for providing spatial calibrations with fixed photoelectric sources in the TPC is also being developed. Results of these studies will be reported.

  15. MicroBooNE: A New Liquid Argon Time Projection Chamber Experiment

    SciTech Connect

    Soderberg, M.

    2009-10-01

    Liquid Argon Time Projection Chamber detectors are well suited to study neutrino interactions, and are an intriguing option for future massive detectors capable of measuring the parameters that characterize neutrino oscillations. These detectors combine fine-grained tracking with calorimetry, allowing for excellent imaging and particle identification ability. In this talk the details of the MicroBooNE experiment, a 175 ton LArTPC which will be exposed to Fermilab's Booster Neutrino Beamline starting in 2011, will be presented. The ability of MicroBooNE to differentiate electrons from photons gives the experiment unique capabilities in low energy neutrino interaction measurements.

  16. Data links for the EOS TPC

    SciTech Connect

    Bieser, F.; Jones, R.; McParland, C.

    1990-10-01

    We report on the design and performance of high speed data links and slower configuration control links used between the EOS TPC detector and the data processing electronics. Data rates of 5MBytes/s/link are maintained over 30m with optical isolation. Pedestal subtraction, hit detection, and data reordering are performed online. 3 refs., 1 fig.

  17. Liquid Argon Time Projection Chamber research and development in the United States

    NASA Astrophysics Data System (ADS)

    Baller, B.; Bromberg, C.; Buchanan, N.; Cavanna, F.; Chen, H.; Church, E.; Gehman, V.; Greenlee, H.; Guardincerri, E.; Jones, B.; Junk, T.; Katori, T.; Kirby, M.; Lang, K.; Loer, B.; Marchionni, A.; Maruyama, T.; Mauger, C.; Menegolli, A.; Montanari, D.; Mufson, S.; Norris, B.; Pordes, S.; Raaf, J.; Rebel, B.; Sanders, R.; Soderberg, M.; St. John, J.; Strauss, T.; Szelc, A.; Tope, T.; Touramanis, C.; Thorn, C.; Urheim, J.; Van de Water, R.; Wang, H.; Yu, B.; Zuckerbrot, M.

    2014-05-01

    A workshop was held at Fermilab on March 20-21, 2013 to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in seven topical plenary sessions: i) Argon Purity, ii) Cryogenics, iii) TPC and High Voltage, iv) Electronics, Data Acquisition and Triggering, v) Scintillation Light Detection, vi) Calibration and Test Beams, and vii) Software. This document summarizes the current efforts in each of these areas. It also highlights areas in LArTPC research and development that are common between neutrino experiments and dark matter experiments.

  18. TPC magnet cryogenic system

    SciTech Connect

    Green, M.A.; Burns, W.A.; Taylor, J.D.; Van Slyke, H.W.

    1980-03-01

    The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar (for liquid nitrogen). The operation o these systems during virtually all phases of system operation are described. Photographs and diagrams of various system components are shown, and cryogenic system data are presented in the following sections: (1) heat leaks into the TPC coil package and the compensation solenoids; (2) heat leaks to various components of the TPC magnet cryogenics system besides the magnets and control dewar; (3) the control dewar and its relationship to the rest of the system; (4) the conditioner system and its role in cooling down the TPC magnet; (5) gas-cooled electrical leads and charging losses; and (6) a summation of the liquid helium and liquid nitrogen requirements for the TPC superconducting magnet system.

  19. Performance of a liquid argon time projection chamber exposed to the CERN West Area Neutrino Facility neutrino beam

    SciTech Connect

    Arneodo, F.; Cavanna, F.; Mitri, I. De; Mortari, G. Piano; Benetti, P.; Borio di Tigliole, A.; Calligarich, E.; Cesana, E.; Dolfini, R.; Mauri, F.; Montanari, C.; Rappoldi, A.; Raselli, G. L.; Rubbia, C.; Terrani, M.; Vignoli, C.; Bonesini, M.; Boschetti, B.; Cavalli, D.; Curioni, A.

    2006-12-01

    We present the results of the first exposure of a Liquid Argon TPC to a multi-GeV neutrino beam. The data have been collected with a 50 liters ICARUS-like chamber located between the CHORUS and NOMAD experiments at the CERN West Area Neutrino Facility (WANF). We discuss both the instrumental performance of the detector and its capability to identify and reconstruct low-multiplicity neutrino interactions.

  20. CAMAC interface for TPC data-acquisition electronics

    SciTech Connect

    Sidman, S.; Olson, S.; Jared, R.

    1983-06-01

    The Time Projection Chamber (TPC) is a detector used for high-energy physics research at the Stanford PEP Accelerator. TPC requires about 17,000 channels of data acquisition, which samples on command the input to each channel at a 10 MHz rate. This high data rate is made possible by means of Charge Coupled Devices (CCDs), intelligent digitizers, and a sophisticated trigger system. The TPC-CAMAC interface described here was developed to allow experiments of smaller scale than the complete TPC to use the standard data acquisition portion of the TPC electronics, namely the amplifier, CCD and digitizer bins. These three bins, when properly interconnected and controlled by the interface control bin, form a transient digitizer with a depth of 455 samples and a maximum width of 256 channels per bin set.

  1. The darkside multiton detector for the direct dark matter search

    DOE PAGESBeta

    Aalseth, C. E.; Agnes, P.; Alton, A.; Arisaka, K.; Asner, D. M.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; et al

    2015-01-01

    Although the existence of dark matter is supported by many evidences, based on astrophysical measurements, its nature is still completely unknown. One major candidate is represented by weakly interacting massive particles (WIMPs), which could in principle be detected through their collisions with ordinary nuclei in a sensitive target, producing observable low-energy (<100 keV) nuclear recoils. The DarkSide program aims at the WIPMs detection using a liquid argon time projection chamber (LAr-TPC). In this paper we quickly review the DarkSide program focusing in particular on the next generation experiment DarkSide-G2, a 3.6-ton LAr-TPC. The different detector components are described as wellmore » as the improvements needed to scale the detector from DarkSide-50 (50 kg LAr-TPC) up to DarkSide-G2. Finally, the preliminary results on background suppression and expected sensitivity are presented.« less

  2. The darkside multiton detector for the direct dark matter search

    SciTech Connect

    Aalseth, C. E.; Agnes, P.; Alton, A.; Arisaka, K.; Asner, D. M.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; Brigatti, A.; Brodsky, J.; Budano, F.; Cadonati, L.; Cadoni, M.; Calaprice, F.; Canci, N.; Candela, A.; Cao, H.; Cariello, M.; Cavalcante, P.; Chepurnov, A.; Cocco, A. G.; Condon, C.; Crippa, L.; D’Angelo, D.; D’Incecco, M.; Davini, S.; De Deo, M.; Derbin, A.; Devoto, A.; Di Eusanio, F.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Forster, G.; Foxe, M.; Franco, D.; Gabriele, F.; Galbiati, C.; Goretti, A.; Grandi, L.; Gromov, M.; Guan, M. Y.; Guardincerri, Y.; Hackett, B.; Herner, K.; Hime, A.; Humble, P.; Hungerford, E.; Ianni, Al.; Ianni, An.; Jaffe, D. E.; Jollet, C.; Keeter, K.; Kendziora, C.; Kidner, S.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Kurlej, A.; Li, P. X.; Lissia, M.; Lombardi, P.; Ludhova, L.; Luitz, S.; Lukyachenko, G.; Ma, Y. Q.; Machulin, I.; Mandarano, A.; Mari, S. M.; Maricic, J.; Marini, L.; Markov, D.; Martoff, J.; Meregaglia, A.; Meroni, E.; Meyers, P. D.; Miletic, T.; Milincic, R.; Montuschi, M.; Monzani, M. E.; Mosteiro, P.; Mount, B.; Muratova, V.; Musico, P.; Montanari, D.; Nelson, A.; Odrowski, S.; Odrzywolek, A.; Orrell, J. L.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Parsells, B.; Pelczar, K.; Pelliccia, N.; Perasso, S.; Perasso, L.; Pocar, A.; Pordes, S.; Pugachev, D.; Qian, H.; Randle, K.; Ranucci, G.; Razeto, A.; Recine, K.; Reinhold, B.; Renshaw, A.; Romani, A.; Rossi, N.; Rossi, B.; Rountree, S. D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Sangiorgio, S.; Segreto, E.; Semenov, D.; Shields, E.; Skorokhvatov, M.; Smallcomb, M.; Smirnov, O.; Sotnikov, A.; Suvurov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Unzhakov, E.; Vogelaar, R. B.; Wada, M.; Walker, S. E.; Wang, H.; Wang, Y.; Watson, A. W.; Westerdale, S.; Williams, R.; Wojcik, M.; Xu, J.; Yang, C. G.; Yoo, J.; Yu, B.; Zavatarelli, S.; Zhong, W. L.; Zuzel, G.

    2015-01-01

    Although the existence of dark matter is supported by many evidences, based on astrophysical measurements, its nature is still completely unknown. One major candidate is represented by weakly interacting massive particles (WIMPs), which could in principle be detected through their collisions with ordinary nuclei in a sensitive target, producing observable low-energy (<100 keV) nuclear recoils. The DarkSide program aims at the WIPMs detection using a liquid argon time projection chamber (LAr-TPC). In this paper we quickly review the DarkSide program focusing in particular on the next generation experiment DarkSide-G2, a 3.6-ton LAr-TPC. The different detector components are described as well as the improvements needed to scale the detector from DarkSide-50 (50 kg LAr-TPC) up to DarkSide-G2. Finally, the preliminary results on background suppression and expected sensitivity are presented.

  3. Results from the STAR TPC system test

    SciTech Connect

    Betts, W.; Bieser, F.; Bossingham, R.

    1996-12-31

    A system test of various components of the Solenoidal Tracker at RHIC (STAR) detector, operating in concern, has recently come on-line. Communication between a major sub-detector, a sector of the Time Projection Chamber (TPC), and the trigger, data acquisition and slow controls systems has been established, enabling data from cosmic ray muons to be collected. First results from an analysis of the TPC data are presented. These include measurements of system noise, electronic parameters such as amplifier gains and pedestal values, and tracking resolution for cosmic ray muons and laser induced ionization tracks. A discussion on the experience gained in integrating the different components for the system test is also given.

  4. The STAR TPC front end electronics

    SciTech Connect

    Klein, S.R.; Barale, P.; Beuville, E.

    1995-10-01

    The Solenoidal Tracker at RHIC (STAR) uses a large time projection chamber. Each of the 136,600 pads is instrumented with a waveform digitizer, implemented in custom low noise preamplifier/shaper and switched capacitor array/ADCs ICs. The system is highly integrated with all analog functions mounted on small cards that plug into the TPC. Detector mounted readout boards multiplex data from 1152 channels onto a 1.5 Gbit/sec fiber optic link to the data acquisition system.

  5. Highly integrated electronics for the star TPC

    SciTech Connect

    Arthur, A.A.; Bieser, F.; Hearn, W.; Kleinfelder, S.; Merrick, T.; Millaud, J.; Noggle, T.; Rai, G.; Ritter, H.G.; Wieman, H.

    1991-12-31

    The concept for the STAR TPC front-end electronics is presented and the progress toward the development of a fully integrated solution is described. It is the goal of the R+D program to develop the complete electronics chain for the STAR central TPC detector at RHIC. It is obvious that solutions chosen e.g. for ALEPH are not adequate for the 150000 channels that need to be instrumented for readout. It will be necessary to perform all the signal processing, digitization and multiplexing directly on the detector in order to reduce per channel cost and the amount of cabling necessary to read out the information. We follow the approach chosen by the EOS TPC project, where the readout electronics on the detector consists of an integrated preamplifier, a hybrid shaping amplifier, an integrated switched capacitor array and a highly multiplexed ADC. The STAR electronics will be further integrated so that approximately 16 channels of the preamplifier, the shaper, the analog store and the ADC will be contained in two integrated circuits located directly on the pad plane.

  6. First Tests of a New Fast Waveform Digitizer for PMT Signal Read-out from Liquid Argon Dark Matter Detectors

    NASA Astrophysics Data System (ADS)

    Szelc, A. M.; Canci, N.; Cavanna, F.; Cortopassi, A.; D'Incecco, M.; Mini, G.; Pietropaolo, F.; Romboli, A.; Segreto, E.; Acciarri, R.

    A new generation Waveform Digitizer board as been recently made available on the market by CAEN. The new board CAEN V1751 with 8 Channels per board, 10 bit, 1 GS/s Flash ADC Waveform Digitizer (or 4 channel, 10 bit, 2 GS/s Flash ADC Waveform Digitizer -Dual Edge Sampling mode) with threshold and Auto-Trigger capabilities provides an ideal (relatively low-cost) solution for reading signals from liquid Argon detectors for Dark Matter search equipped with an array of PMTs for the detection of scintillation light. The board was extensively used in real experimental conditions to test its usefulness for possible future uses and to compare it with a state of the art digital oscilloscope. As results, PMT Signal sampling at 1 or 2 GS/s is appropriate for the reconstruction of the fast component of the signal scintillation in Argon (characteristic time of about 4 ns) and the extended dynamic range, after a small customization, allows for the detection of signals in the range of energy needed. The bandwidth is found to be adequate and the intrinsic noise is very low.

  7. Reconstructing Michel Electrons in the MicroBooNE Detector

    NASA Astrophysics Data System (ADS)

    Caratelli, David

    2016-03-01

    MicroBooNE is a Liquid Argon Time Projection Chamber (LArTPC) neutrino detector located in the Booster Neutrino Beamline at Fermilab which began collecting neutrino data in October 2015. MicroBooNE aims to explore the low-energy excess in the νe spectrum reported by MiniBooNE as well as perform ν-Ar cross-section measurements. In this talk, we present the current status of reconstructing Michel electrons from cosmic ray muons in the MicroBooNE detector. These Michel electrons are distributed uniformly inside the detector, and serve as a natural and powerful calibration source to study the detector's response for low energy (10s of MeV) interactions as a function of position. We have developed a reconstruction software tool to successfully identify such Michel electrons which could be of benefit to LArTPC experiments generically.

  8. ALICE TPC commissioning results

    NASA Astrophysics Data System (ADS)

    Larsen, D. T.; Alice Tpc Collaboration

    2010-05-01

    ALICE is a dedicated heavy-ion experiment at CERN LHC aiming to study the properties of the quark-gluon plasma. A lead-lead collision might produce several 10 00 new particles. Detailed study of the event requires precise measurements of the particle tracks. A 90 m3 Time Projection Chamber (TPC) with more than 500 000 read-out pads was built as the main central barrel tracker. Collisions can be recorded at a rate of up to about 1 kHz. The front-end electronics, designed from FPGAs and custom ASICs, performs shaping, amplification, digitisation and digital filtering of the signals. The data are forwarded to DAQ via 216 1.25 Gb/s fibre-optical links. Configuration, control and monitoring is done by an embedded Linux system on the front-end electronics. Before production runs with beam, extensive commissioning using tracks from cosmics and from the laser system as well as clusters from radioactive krypton gas is needed. Extensive results have been obtained with respect to the performance of the TPC including its sub-systems.

  9. Precision calibration of calorimeter electronics in the D0 liquid argon/uranium particle detector

    SciTech Connect

    Huffman, D.L.

    1991-12-01

    The ability to cross calibrate thousands of channels of detector electronics is of prime importance. This paper will describe the system used to deliver and distribute a 300 nanosecond pulse across 50,000 channels of electronics with better than 0.25% difference between channels from a location more than 200 feet away. The system is used for both cross calibration and functionality checking, (i.e., missing channels). Design of a fixed width pulse generator of high stability is presented as a key ingredient in the system`s overall performance. In addition, the design of a controlled impedance distribution system is discussed. 2 refs.

  10. The DarkSide-50 outer detectors

    NASA Astrophysics Data System (ADS)

    Westerdale, S.; Agnes, P.; Agostino, L.; Albuquerque, I. F. M.; Alexander, T.; Alton, A. K.; Arisaka, K.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; Bottino, B.; Brigatti, A.; Brodsky, J.; Budano, F.; Bussino, S.; Cadeddu, M.; Cadonati, L.; Cadoni, M.; Calaprice, F.; Canci, N.; Candela, A.; Cao, H.; Cariello, M.; Carlini, M.; Catalanotti, S.; Cavalcante, P.; Chepurnov, A.; Cocco, A. G.; Covone, G.; D’Angelo, D.; D’Incecco, M.; Davini, S.; De Cecco, S.; De Deo, M.; De Vincenzi, M.; Derbin, A.; Devoto, A.; Di Eusanio, F.; Di Pietro, G.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Foster, G.; Franco, D.; Gabriele, F.; Galbiati, C.; Giganti, C.; Goretti, A. M.; Granato, F.; Grandi, L.; Gromov, M.; Guan, M.; Guardincerri, Y.; Hackett, B. R.; Herner, K. R.; Hungerford, E. V.; Aldo, Ianni; Andrea, Ianni; James, I.; Jollet, C.; Keeter, K.; Kendziora, C. L.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Kubankin, A.; Li, X.; Lissia, M.; Lombardi, P.; Luitz, S.; Ma, Y.; Machulin, I. N.; Mandarano, A.; Mari, S. M.; Maricic, J.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Meyers, P. D.; Miletic, T.; Milincic, R.; Montanari, D.; Monte, A.; Montuschi, M.; Monzani, M. E.; Mosteiro, P.; Mount, B. J.; Muratova, V. N.; Musico, P.; Napolitano, J.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Pelczar, K.; Pelliccia, N.; Perasso, S.; Pocar, A.; Pordes, S.; Pugachev, D. A.; Qian, H.; Randle, K.; Ranucci, G.; Razeto, A.; Reinhold, B.; Renshaw, A. L.; Romani, A.; Rossi, B.; Rossi, N.; Rountree, S. D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Sangiorgio, S.; Savarese, C.; Segreto, E.; Semenov, D. A.; Shields, E.; Singh, P. N.; DSkorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Stanford, C.; Suvorov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Trinchese, P.; Unzhakov, E. V.; Vishneva, A.; Vogelaar, B.; Wada, M.; Walker, S.; Wang, H.; Wang, Y.; Watson, A. W.; Wilhelmi, J.; Wojcik, M. M.; Xiang, X.; Xu, J.; Yang, C.; Yoo, J.; Zavatarelli, S.; Zec, A.; Zhong, W.; Zhu, C.; Zuzel, G.; The DarkSide Collaboration

    2016-05-01

    DarkSide-50 is a dark matter detection experiment searching for Weakly Interacting Massive Particles (WIMPs), in Gran Sasso National Laboratory. For experiments like DarkSide-50, neutrons are one of the primary backgrounds that can mimic WIMP signals. The experiment consists of three nested detectors: a liquid argon time projection chamber surrounded by two outer detectors. The outermost detector is a 10 m by 11 m cylindrical water Cherenkov detector with 80 PMTs, designed to provide shielding and muon vetoing. Inside the water Cherenkov detector is the 4 m diameter spherical boron-loaded liquid scintillator veto, with a cocktail of pseudocumene, trimethyl borate, and PPO wavelength shifter, designed to provide shielding, neutron vetoing, and in situ measurements of the TPC backgrounds. We present design and performance details of the DarkSide-50 outer detectors.

  11. A measurement of the absorption of liquid argon scintillation light by dissolved nitrogen at the part-per-million level

    NASA Astrophysics Data System (ADS)

    Jones, B. J. P.; Chiu, C. S.; Conrad, J. M.; Ignarra, C. M.; Katori, T.; Toups, M.

    2013-07-01

    We report on a measurement of the absorption length of scintillation light in liquid argon due to dissolved nitrogen at the part-per-million (ppm) level. We inject controlled quantities of nitrogen into a high purity volume of liquid argon and monitor the light yield from an alpha source. The source is placed at different distances from a cryogenic photomultiplier tube assembly. By comparing the light yield from each position we extract the absorption cross section of nitrogen. We find that nitrogen absorbs argon scintillation light with strength of (1.51±0.15) × 10-4 cm-1ppm-1, corresponding to an absorption cross section of (4.99±0.51) × 10-21 cm2molecule-1. We obtain the relationship between absorption length and nitrogen concentration over the 0 to 50 ppm range and discuss the implications for the design and data analysis of future large liquid argon time projection chamber (LArTPC) detectors. Our results indicate that for a current-generation LArTPC, where a concentration of 2 parts per million of nitrogen is expected, the attenuation length due to nitrogen will be 30±3 meters.

  12. Depleted Argon from Underground Sources

    SciTech Connect

    Back, H. O.; Galbiati, C.; Goretti, A.; Loer, B.; Montanari, D.; Mosteiro, P.; Alexander, T.; Alton, A.; Rogers, H.; Kendziora, C.; Pordes, S.

    2011-04-27

    Argon is a strong scintillator and an ideal target for Dark Matter detection; however {sup 39}Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in {sup 39}Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO{sub 2} well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO{sub 2}. We first concentrate the argon locally to 3% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation, and then the N{sub 2} and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO{sub 2} facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

  13. Anode-coupled readout for light collection in Liquid Argon TPCs

    NASA Astrophysics Data System (ADS)

    Moss, Z.; Toups, M.; Bugel, L.; Collin, G. H.; Conrad, J. M.

    2016-03-01

    This paper will discuss a new method of signal read-out from photon detectors in ultra-large, underground liquid argon time projection chambers. In this design, the signal from the light collection system is coupled via capacitive plates to the TPC wire-planes. This signal is then read out using the same cabling and electronics as the charge information. This greatly benefits light collection: it eliminates the need for an independent readout, substantially reducing cost; it reduces the number of cables in the vapor region of the TPC that can produce impurities; and it cuts down on the number of feed-throughs in the cryostat wall that can cause heat-leaks and potential points of failure. We present experimental results that demonstrate the sensitivity of a LArTPC wire plane to photon detector signals. We also simulate the effect of a 1 μs shaping time and a 2 MHz sampling rate on these signals in the presence of noise, and find that a single photoelectron timing resolution of ~30 ns can be achieved.

  14. Readout system of TPC/MPD NICA project

    NASA Astrophysics Data System (ADS)

    Averyanov, A. V.; Bajajin, A. G.; Chepurnov, V. F.; Cheremukhina, G. A.; Fateev, O. V.; Korotkova, A. M.; Levchanovskiy, F. V.; Lukstins, J.; Movchan, S. A.; Razin, S. V.; Rybakov, A. A.; Vereschagin, S. V.; Zanevsky, Yu. V.; Zaporozhets, S. A.; Zruyev, V. N.

    2015-12-01

    The time-projection chamber (TPC) is the main tracking detector in the MPD/NICA. The information on charge-particle tracks in the TPC is registered by the MWPG with cathode pad readout. The frontend electronics (FEE) are developed with use of modern technologies such as application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), and data transfer to a concentrator via a fast optical interface. The main parameters of the FEE are as follows: total number of channels, ~95 000; data stream from the whole TPC, 5 GB/s; low power consumption, less than 100 mW/ch; signal to noise ratio (S/N), 30; equivalent noise charge (ENC), <1000e- ( C in = 10-20 pF); and zero suppression (pad signal rejection ~90%). The article presents the status of the readout chamber construction and the data acquisition system. The results of testing FEE prototypes are presented.

  15. Spatial resolution of the PEP-4 time projection chamber - The PEP-4 TPC collaboration

    SciTech Connect

    Aihara, H.; Alston-Garnjost, M.; Badtke, D.H.; Bakken, J.A.; Barbaro-Galtier, A.; Barnes, A.V.; Barnett, B.A.; Blumenfeld, B.

    1983-02-01

    The spatial resolution and response of the segmented cathode pads of the PEP- 4 TPC have been measured with data taken at 8.5 atmospheres of 80% Argon-20% Methane gas with a 4kG magnetic field. The dependence of the spatial resolution and pad response on drift distance and track-anode crossing angle is presented.

  16. CAPTAIN-Minerνa. Neutrino-Argon Scattering in a Medium-Energy Neutrino Beam

    SciTech Connect

    Mauger, Christopher M.

    2015-10-29

    The NuMI facility at Fermilab is currently providing an extremely intense beam of neutrinos for the NOνA, MINERνA and MINOS+ experiments. By installing the 5-ton CAPTAIN liquid argon TPC in front of the MINERνA detector in the NuMI beamline and combining the data from the CAPTAIN, MINERνA and MINOS+ detectors, a broad program of few-GeV neutrino cross section measurements on argon can be pursued. These measurements will be extremely helpful for future oscillation experiments. By directly comparing the cross sections on argon to MINERνA’s scintillator (CH) target, a new level of precision can be achieved in the measurements of the effects of the nucleus on neutrino interactions. These effects are of interest to not only the particle physics but also the nuclear physics community. This document describes in detail the physics goals of the CAPTAIN-MINERνA experiment, in addition to a first estimate of the technical resources required to install, commission and operate the CAPTAIN detector in front of the MINERVA detector.

  17. Future upgrade and physics perspectives of the ALICE TPC

    NASA Astrophysics Data System (ADS)

    Gunji, Taku

    2014-11-01

    The ALICE experiment at the Large Hadron Collider (LHC) proposes major detector upgrades to fully exploit the increase of the luminosity of the LHC in RUN 3 and to extend the physics reach for rare probes at low transverse momentum. The Time Projection Chamber (TPC) is one of the main tracking and PID devices in the central barrel of ALICE. The maximum trigger rate of the TPC is currently limited to about 3.5 kHz by the operation of a gating grid system. In order to make full use of the luminosity in RUN 3, the TPC is foreseen to be operated in an ungated mode with continuous readout. The existing MWPC readout will be replaced by a Micro-Pattern Gaseous Detector (MPGD) based readout, which provides intrinsic ion capture capability without gating. Extensive detector R&D employing Gas Electron Multiplier (GEM) and Micro-Mesh Gaseous detector (Micromegas) technologies, and simulation studies to advance the techniques for the corrections of space-charge distortions have been performed since 2012. In this paper, the expected detector performance and the status of the R&D program to achieve this ambitious goal are described.

  18. Simulation of the transition radiation detection conditions in the ATLAS TRT detector filled with argon and krypton gas mixtures

    SciTech Connect

    Boldyrev, A. S.; Maevskiy, A. S.

    2015-12-15

    Performance of the Transition Radiation Tracker (TRT) at the ATLAS experiment with argon and krypton gas mixtures was simulated. The efficiency of transition radiation registration, which is necessary for electron identification, was estimated along with the electron identification capabilities under such conditions.

  19. Summary of the second workshop on liquid argon time projection chamber research and development in the United States

    NASA Astrophysics Data System (ADS)

    Acciarri, R.; Adamowski, M.; Artrip, D.; Baller, B.; Bromberg, C.; Cavanna, F.; Carls, B.; Chen, H.; Deptuch, G.; Epprecht, L.; Dharmapalan, R.; Foreman, W.; Hahn, A.; Johnson, M.; Jones, B. J. P.; Junk, T.; Lang, K.; Lockwitz, S.; Marchionni, A.; Mauger, C.; Montanari, C.; Mufson, S.; Nessi, M.; Olling Back, H.; Petrillo, G.; Pordes, S.; Raaf, J.; Rebel, B.; Sinins, G.; Soderberg, M.; Spooner, N. J. C.; Stancari, M.; Strauss, T.; Terao, K.; Thorn, C.; Tope, T.; Toups, M.; Urheim, J.; Van de Water, R.; Wang, H.; Wasserman, R.; Weber, M.; Whittington, D.; Yang, T.

    2015-07-01

    The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the current efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world.

  20. Summary of the Second Workshop on Liquid Argon Time Projection Chamber Research and Development in the United States

    SciTech Connect

    Acciarri, R.; et al.

    2015-04-21

    The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the current efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world.

  1. Summary of the Second Workshop on Liquid Argon Time Projection Chamber Research and Development in the United States

    SciTech Connect

    Acciarri, R.; Adamowski, M.; Artrip, D.; Baller, B.; Bromberg, C.; Cavanna, F.; B. Carls; Chen, H.; Deptuch, G.; Epprecht, L.; Dharmapalan, R.; Foreman, W.; Hahn, A.; Johnson, M.; Jones, B. J.P.; Junk, T.; Lang, K.; Lockwitz, S.; Marchionni, A.; Mauger, C.; Montanari, C.; Mufson, S.; Nessi, M.; Back, H. Olling; Petrillo, G.; Pordes, S.; Raaf, J.; Rebel, B.; Sinins, G.; Soderberg, M.; Spooner, N.; Stancari, M.; Strauss, T.; Terao, K.; Thorn, C.; Tope, T.; Toups, M.; Urheim, J.; Water, R. Van de; Wang, H.; Wasserman, R.; Weber, M.; Whittington, D.; Yang, T.

    2015-07-28

    The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the current efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world.

  2. Summary of the Second Workshop on Liquid Argon Time Projection Chamber Research and Development in the United States

    DOE PAGESBeta

    Acciarri, R.; Adamowski, M.; Artrip, D.; Baller, B.; Bromberg, C.; Cavanna, F.; B. Carls; Chen, H.; Deptuch, G.; Epprecht, L.; et al

    2015-07-28

    The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the currentmore » efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world.« less

  3. A continuous read-out TPC for the ALICE upgrade

    NASA Astrophysics Data System (ADS)

    Lippmann, C.

    2016-07-01

    The largest gaseous Time Projection Chamber (TPC) in the world, the ALICE TPC, will be upgraded based on Micro Pattern Gas Detector technology during the second long shutdown of the CERN Large Hadron Collider in 2018/19. The upgraded detector will operate continuously without the use of a triggered gating grid. It will thus be able to read all minimum bias Pb-Pb events that the LHC will deliver at the anticipated peak interaction rate of 50 kHz for the high luminosity heavy-ion era. New read-out electronics will send the continuous data stream to a new online farm at rates up to 1 TByte/s. A fractional ion feedback of below 1% is required to keep distortions due to space charge in the TPC drift volume at a tolerable level. The new read-out chambers will consist of quadruple stacks of Gas Electron Multipliers (GEM), combining GEM foils with a different hole pitch. Other key requirements such as energy resolution and operational stability have to be met as well. A careful optimisation of the performance in terms of all these parameters was achieved during an extensive R&D program. A working point well within the design specifications was identified with an ion backflow of 0.63%, a local energy resolution of 11.3% (sigma) and a discharge probability comparable to that of standard triple GEM detectors.

  4. A large liquid argon time projection chamber for long-baseline, off-axis neutrino oscillation physics with the NuMI beam

    SciTech Connect

    Finley, D.; Jensen, D.; Jostlein, H.; Marchionni, A.; Pordes, S.; Rapidis, P.A.; Bromberg, C.; Lu, C.; McDonald, T.; Gallagher, H.; Mann, A.; Schneps, J.; Cline, D.; Sergiampietri, F.; Wang, H.; Curioni, A.; Fleming, B.T.; Menary, S.; /York U., Canada

    2005-09-01

    Results from neutrino oscillation experiments in the last ten years have revolutionized the field of neutrino physics. While the overall oscillation picture for three neutrinos is now well established and precision measurements of the oscillation parameters are underway, crucial issues remain. In particular, the hierarchy of the neutrino masses, the structure of the neutrino mixing matrix, and, above all, CP violation in the neutrino sector are the primary experimental challenges in upcoming years. A program that utilizes the newly commissioned NuMI neutrino beamline, and its planned upgrades, together with a high-performance, large-mass detector will be in an excellent position to provide decisive answers to these key neutrino physics questions. A Liquid Argon time projection chamber (LArTPC) [2], which combines fine-grained tracking, total absorption calorimetry, and scalability, is well matched for this physics program. The few-millimeter-scale spatial granularity of a LArTPC combined with dE/dx measurements make it a powerful detector for neutrino oscillation physics. Scans of simulated event samples, both directed and blind, have shown that electron identification in {nu}{sub e} charged current interactions can be maintained at an efficiency of 80%. Backgrounds for {nu}{sub e} appearance searches from neutral current events with a {pi}{sup 0} are reduced well below the {approx} 0.5-1.0% {nu}{sub e} contamination of the {nu}{sub {mu}} beam [3]. While the ICARUS collaboration has pioneered this technology and shown its feasibility with successful operation of the T600 (600-ton) LArTPC [4], a detector for off-axis, long-baseline neutrino physics must be many times more massive to compensate for the low event rates. We have a baseline concept [5] based on the ICARUS wire plane structure and commercial methods of argon purification and housed in an industrial liquefied-natural-gas tank. Fifteen to fifty kton liquid argon capacity tanks have been considered. A very

  5. Readout system of TPC/MPD NICA project

    SciTech Connect

    Averyanov, A. V.; Bajajin, A. G.; Chepurnov, V. F.; Cheremukhina, G. A.; Fateev, O. V.; Korotkova, A. M.; Levchanovskiy, F. V.; Lukstins, J.; Movchan, S. A.; Razin, S. V.; Rybakov, A. A.; Vereschagin, S. V. Zanevsky, Yu. V.; Zaporozhets, S. A.; Zruyev, V. N.

    2015-12-15

    The time-projection chamber (TPC) is the main tracking detector in the MPD/NICA. The information on charge-particle tracks in the TPC is registered by the MWPG with cathode pad readout. The frontend electronics (FEE) are developed with use of modern technologies such as application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), and data transfer to a concentrator via a fast optical interface. The main parameters of the FEE are as follows: total number of channels, ∼95 000; data stream from the whole TPC, 5 GB/s; low power consumption, less than 100 mW/ch; signal to noise ratio (S/N), 30; equivalent noise charge (ENC), <1000e{sup –} (C{sub in} = 10–20 pF); and zero suppression (pad signal rejection ∼90%). The article presents the status of the readout chamber construction and the data acquisition system. The results of testing FEE prototypes are presented.

  6. The iTPC upgrade for BES-II

    NASA Astrophysics Data System (ADS)

    Videbaek, Flemming; STAR Collaboration

    2015-10-01

    STAR has proposed to upgrade the inner sectors of the STAR TPC to increase the segmentation on the inner padplane and to renew the inner sector wires. The upgrade will provide better momentum resolution, better dE/dx resolution and, most importantly, it will provide improved acceptance at high rapidity to | η| <= 1.5 compared to the current TPC configuration of | η| <= 1 and to extend the pt coverage towards lower pt. The enhanced measurement capabilities of STAR after the iTPC upgrade are a vital part of the BES-II effort for 2019-2020. The expanded rapidity coverage provides a major benefit for many analyses, especially those sensitive to changes in correlation lengths near a critical point, like the net-proton Kurtosis which exhibits interesting energy trends that only appear near the edge of the current STAR acceptance. In the area of dielectron measurements it reduces hadron contamination from a dominant source of uncertainty to an expected statistical uncertainty of only 10%, and will enable significantly improved understanding of in-medium modifications. In this talk I will discuss the physics impact and give a technical overview of the detector upgrade. This work was supported in part by the Office of Nuclear Physics within the U.S. DOE Office of Science.

  7. The EOS TPC analysis shell

    SciTech Connect

    Olson, D.L.

    1991-03-01

    Key features of the general purpose event-based-data analysis shell (TAS) for the EOS TPC at LBL are described including the code development/code management procedures used. The architecture is designed with a view towards a distributed and multi-processing environment. TAS is interfaced seamlessly with the CERN PAW program and provides a consistent environment for both on-line and off-line analysis. The data model used is relational tables and the data structure definitions are maintained in a commercial database (INFORMIX). The interface for analysis modules is specified and enhances group participation in the development process. The use of commercial database as a data dictionary for both the table definitions and parameters used in the TAS kernel is extremely useful and productive. 6 refs., 4 figs.

  8. Protonated water clusters in TPC's

    NASA Astrophysics Data System (ADS)

    Kaya, Yunus; Kalkan, Yalçın; Veenhof, Rob

    2016-07-01

    Water vapour is added to the ALICE TPC gas to enhance its stability. These polar molecules create large protonated water clusters around a H+ core. In this context, the reactions H3O+(H2O)n-1 +H2 O →H3O+(H2O)n (n=1-9) were studied in the gas phase. Structures for these clusters are suggested and the most stable structures for each cluster size are shown. The thermodynamic parameters Δ Hn-1,n0,Δ Gn-1,n0,Δ Sn-1,n0 and equilibrium constants Kn-1,n for the reaction were calculated to determine the size of the water clusters. The results are close to experimental data found in the literature. Protonated water clusters at stp have a size of 6-9 which corresponds to a mass of 127.1 - 181.2 g / mole.

  9. Depleted argon from underground sources

    SciTech Connect

    Back, H.O.; Alton, A.; Calaprice, F.; Galbiati, C.; Goretti, A.; Kendziora, C.; Loer, B.; Montanari, D.; Mosteiro, P.; Pordes, S.; /Fermilab

    2011-09-01

    Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

  10. Test Beam Results for ALICE TPC Upgrade Prototypes

    NASA Astrophysics Data System (ADS)

    Mulligan, James; Alice Tpc-Upgrade Collaboration

    2015-04-01

    The ALICE detector is one of four major experiments at the Large Hadron Collider (LHC), and its main purpose is to study the quark-gluon plasma created in relativistic heavy ion collisions. The Time Projection Chamber (TPC) is the main tracking detector within ALICE, and currently has an intrinsic rate limitation of 3 kHz. The LHC will be upgraded during Long Shutdown 2 in 2018 to have Pb-Pb collision rates up to 50 kHz, and so the TPC readout must be accordingly upgraded. This will be done by replacing the current Multi-Wire Proportional Chamber assembly, which uses a gating grid to prevent ion backflow, with Micro-Pattern Gas Detectors such as Gas Electron Multipliers (GEMs) and Micro-Mesh Gaseous Structures (MMGs), which allow for continuous rather than gated readout. A substantial R&D effort is underway for a 4-GEM design, as well as an alternate 2-GEM/MMG design. Prototypes of each design were tested in November-December 2014 at the PS and SPS beams at CERN; the results for the 2-GEM/MMG chambers will be presented.

  11. Two experiments in neutrino physics: Double beta decay of cadmium-116 and the efficiency of an argon-40 neutrino detector

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Manojeet

    1999-03-01

    This thesis contains work concerning two experiments related to searches for neutrino masses. 1. QRPA calculations of double-β-decays have not been able to reproduce data in the A = 100 system. We propose the A = 116 system-because of its smaller deformation-as a simpler system to test QRPA calculations. We performed two experiments that determine the previously unknown electron capture (EC) decay branch of 116In to be (2.27 ± 0.63) × 10- 2%, from which we deduce logft = 4.39- 0.15+0.10. We then used this EC logft value along with the well known βsp- logft values to predict the 2ν double-β decay rate of 116Cd to the g.s. and the first excited 0+ state of 116Sn. The prediction shows that the contribution to the double-β decay rate from the g.s could exceed the total decay rate indicating a cancellation of contributions from the excited states of 116In. 2. We studied β-delayed proton and γ emission from 40Ti decay. We found t1/over 2 = 53.6 ± 0.6 ms and observed 28 proton groups that we organized into a 40Ti decay with 21 branches. The reduced transition strengths of these decay branches were then used to compute the neutrino detection efficiency of the ICARUS liquid argon time-projection chamber. Our integrated GT strength is about 20% larger than the theoretical prediction. We found 40Ar(/nu,e) cross-sections (for an electron energy threshold W = 5 MeV) of (13.8 ± 0.3) × 10-43cm2, (74.0 ± 1.6) × 10- 43cm2 and (3.2 ± 0.1) × 10- 41cm2 for 8B neutrinos, hep neutrinos and supernova neutrinos characterized by a temperature of 4.5 MeV.

  12. Design and Analysis for the DarkSide-10 Two-Phase Argon Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Love, Christina Elena

    Astounding evidence for invisible "dark" matter has been found from galaxy clusters, cosmic and stellar gas motion, gravitational lensing studies, cosmic microwave background analysis, and large scale galaxy surveys. Although all studies indicate that there is a dominant presence of non-luminous matter in the universe (about 22 percent of the total energy density with 5 times more dark matter than baryonic matter), its identity and its "direct" detection (through non-gravitational effects) has not yet been achieved. Dark matter in the form of massive, weakly interacting particles (WIMPs) could be detected through their collisions with target nuclei. This requires detectors to be sensitive to very low-energy (less than 100 keV) nuclear recoils with very low expected rates (a few interactions per year per ton of target). Reducing the background in a direct dark matter detector is the biggest challenge. A detector capable of seeing such low-energy nuclear recoils is difficult to build because of the necessary size and the radio- and chemical- purity. Therefore it is imperative to first construct small-scale prototypes to develop the necessary technology and systems, before attempting to deploy large-scale detectors in underground laboratories. Our collaboration, the DarkSide Collaboration, utilizes argon in two-phase time projection chambers (TPCs). We have designed, built, and commissioned DarkSide-10, a 10 kg prototype detector, and are designing and building DarkSide-50, a 50 kg dark matter detector. The present work is an account of my contribution to these efforts. The two-phase argon TPC technology allows powerful discrimination between dark matter nuclear recoils and background events. Presented here are simulations, designs, and analyses involving the electroluminescence in the gas phase from extracted ionization charge for both DarkSide-10 and DarkSide-50. This work involves the design of the HHV systems, including field cages, that are responsible for

  13. Image Processing Techniques applied to Liquid Argon Time Projection Chamber Data

    NASA Astrophysics Data System (ADS)

    Esquivel, Jessica; MicroBooNE Collaboration

    2015-04-01

    Large scale Liquid Argon Time Projection Chambers(LArTPC), like MicroBooNE, offer new ways to study neutrino cross sections and neutrino oscillations. The data from these LArTPCs are very detailed images of charged particles passing through the detector. A plethora of hit finding, cluster finding and tracking algorithms have been implemented to process data coming from MicroBooNE, but it is still possible that particle tracks that are easily visible by eye are being missed during data processing. Because the human eye sometimes does a better job at finding particle tracks that are sometimes missed by data processing, using Image Processing algorithms which emulate the human eye in conjunction with the already implemented algorithms could be beneficial. In particular Edge Detection algorithms could be useful due to the fact that tracks will often have defined deposited energy along straight lines. This talk will cover preliminary data processed with Edge Detection algorithms, and discussion of what the potential benefits are to this approach to LArTPC data analysis. On behalf of the MicroBooNE Collaboration.

  14. Analysis of TPC Single Sextant U-238/U-235 Engineering In-Beam Data

    SciTech Connect

    Tony Hill

    2012-09-01

    The Time Projection Chamber is a collaborative effort to implement an innovative approach and deliver unprecedented fission measurements to DOE programs. This 4p- detector system will provide unrivaled 3-D data about the fission process. This TPC has been shipped and installed at LANSCE and is collecting further engineering data for the full system scale up next year.

  15. Effects of high beam rates on TPC's

    SciTech Connect

    Etkin, A.; Eiseman, S.E.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C. ); Lindenbaum, S.J. City Coll., New York, NY ); Hallman, T.J. ); Chan, C.S.; Kramer, M.A.; Zhao, K.H.; Zhu, Y. (C

    1992-02-06

    The TPC's (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchroton) were exposed to silicon ion fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to measure the distortion of the electric field caused by positive ions in the drift region. Results of these tests are presented and the consequences for the TPC based experiment at RHIC (Relativistic Heavy Ion Collider) are discussed.

  16. Cryogenic testing of the TPC superconducting solenoid

    NASA Astrophysics Data System (ADS)

    Green, M. A.; Smits, R. G.; Taylor, J. D.; Vanslyke, V.; Barrera, F.; Petersen, H.; Rago, C. E.; Rinta, R. I.; Talaska, D.; Watt, R. D.

    1983-06-01

    This report describes the results of a series of tests on the TPC superconducting magnet cryogenic system which occurred during the winter and spring of 1983. The tests occurred at interaction region 2 of the PEP colliding beam facility at the Stanford Linear Accelerator Center (SLAC). The TPC Magnet Cryogenic System which was tested includes the following major components: a remote helium compressor with a full flow liquid nitrogen purification station, 400 meters of high pressure supply and low pressure return lines; and locally a CTi Model 2800 refrigerator with two Sulzer gas bearing turbines, the TPC magnet control dewar, 70 meters of transfer lines, and the TPC thin superconducting solenoid magnet. In addition, there is a conditioner (liquid nitrogen heat exchangers and gas heaters) system for cooldown and warmup of the magnet. This report describes the local cryogenic system and describes the various steps in the cooldown and operation of the TPC magnet. The tests were successful in that they showed that the TPC magnet could be cooled down in 24 hours and the magnet could be operated on the refrigerator or a helium pump with adequate cooling margin.

  17. A time projection chamber for high-rate experiments: Towards an upgrade of the ALICE TPC

    NASA Astrophysics Data System (ADS)

    Ketzer, Bernhard

    2013-12-01

    A Time Projection Chamber (TPC) is a powerful detector for three-dimensional tracking and particle identification for ultra-high multiplicity events. It is the central tracking device of many experiments, e.g. of the ALICE experiment at CERN. The necessity of a switching electrostatic gate, which prevents ions produced in the amplification region of the MWPCs from entering the drift volume, however, restricts its application to trigger rates of the order of 1 kHz. Charge amplification by Gas Electron Multiplier (GEM) foils instead of proportional wires offers an intrinsic suppression of the ion backflow, although not to the same level as a gating grid. Detailed Monte Carlo simulations have shown that the distortions due to residual space charge from back-drifting ions can be limited to a few cm, and thus can be corrected using standard calibration techniques. A prototype GEM-TPC has been built with the largest active volume to date for a detector of this type. It has been commissioned with cosmic rays and with particle beams at the FOPI experiment at GSI, and was employed for a physics measurement with pion beams. For the future operation of the ALICE TPC at the CERN LHC beyond 2019, where Pb-Pb collision rates of 50 kHz are expected, it is planned to replace the existing MWPCs by GEM detectors, operated in a continuous, triggerless readout mode, thus allowing an increase in event rate by a factor of 100. As a first step of the R&D program, a prototype of an Inner Readout Chamber was equipped with large-size GEM foils and exposed to beams of protons, pions and electrons from the CERN PS. In this paper, new results are shown concerning ion backflow, spatial and momentum resolution of the FOPI GEM-TPC, detector calibration, and dE/dx resolution with both detector prototypes. The perspectives of a GEM-TPC for ALICE with continuous readout will be discussed.

  18. TPC spectrometer for measuring the e/sup +/ spectrum in. mu. decay

    SciTech Connect

    Kinnison, W.W.

    1983-01-01

    The Time Projection Chamber (TPC) being used at the Los Alamos Meson Physics Facility (LAMPF) for a high-statistics normal muon-decay experiment is described. It is shown how the experiment will improve upon the limits of the weak-interaction coupling constants by a factor of 5 through the measurement of the positron momentum and direction of emission with respect to the muon-polarization vector for 10/sup 8/ decays of stopped, polarized, positive muons. The TPC apparatus is described, and it is shown that even though more work is to be done to improve the detector acceptance and individual coordinate resolutions, for certain track topologies, the TPC already has a momentum resolution of 0.7% (sigma).

  19. Enhanced trigger for the NIFFTE fissionTPC in presence of high-rate alpha backgrounds

    NASA Astrophysics Data System (ADS)

    Bundgaard, Jeremy; Niffte Collaboration

    2015-10-01

    Nuclear physics and nuclear energy communities call for new, high precision measurements to improve existing fission models and design next generation reactors. The Neutron Induced Fission Fragment Tracking experiment (NIFFTE) has developed the fission Time Projection Chamber (fissionTPC) to measure neutron induced fission with unrivaled precision. The fissionTPC is annually deployed to the Weapons Neutron Research facility at Los Alamos Neutron Science Center where it operates with a neutron beam passing axially through the drift volume, irradiating heavy actinide targets to induce fission. The fissionTPC was developed at the Lawrence Livermore National Laboratory's TPC lab, where it measures spontaneous fission from radioactive sources to characterize detector response, improve performance, and evolve the design. To measure 244Cm, we've developed a fission trigger to reduce the data rate from alpha tracks while maintaining a high fission detection efficiency. In beam, alphas from 239Pu are a large background when detecting fission fragments; implementing the fission trigger will greatly reduce this background. The implementation of the cathode fission trigger in the fissionTPC will be presented along with a detailed study of its efficiency.

  20. Solar neutrino detection in a large volume double-phase liquid argon experiment

    NASA Astrophysics Data System (ADS)

    Franco, D.; Giganti, C.; Agnes, P.; Agostino, L.; Bottino, B.; Canci, N.; Davini, S.; De Cecco, S.; Fan, A.; Fiorillo, G.; Galbiati, C.; Goretti, A. M.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; Jollet, C.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Pagani, L.; Pallavicini, M.; Pantic, E.; Pocar, A.; Razeti, M.; Renshaw, A. L.; Rossi, B.; Rossi, N.; Suvorov, Y.; Testera, G.; Tonazzo, A.; Wang, H.; Zavatarelli, S.

    2016-08-01

    Precision measurements of solar neutrinos emitted by specific nuclear reaction chains in the Sun are of great interest for developing an improved understanding of star formation and evolution. Given the expected neutrino fluxes and known detection reactions, such measurements require detectors capable of collecting neutrino-electron scattering data in exposures on the order of 1 ktonne-yr, with good energy resolution and extremely low background. Two-phase liquid argon time projection chambers (LAr TPCs) are under development for direct Dark Matter WIMP searches, which possess very large sensitive mass, high scintillation light yield, good energy resolution, and good spatial resolution in all three cartesian directions. While enabling Dark Matter searches with sensitivity extending to the ``neutrino floor'' (given by the rate of nuclear recoil events from solar neutrino coherent scattering), such detectors could also enable precision measurements of solar neutrino fluxes using the neutrino-electron elastic scattering events. Modeling results are presented for the cosmogenic and radiogenic backgrounds affecting solar neutrino detection in a 300 tonne (100 tonne fiducial) LAr TPC operating at LNGS depth (3,800 meters of water equivalent). The results show that such a detector could measure the CNO neutrino rate with ~15% precision, and significantly improve the precision of the 7Be and pep neutrino rates compared to the currently available results from the Borexino organic liquid scintillator detector.

  1. The Liquid Argon Purity Demonstrator

    SciTech Connect

    Adamowski, M.; Carls, B.; Dvorak, E.; Hahn, A.; Jaskierny, W.; Johnson, C.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Stancari, M.; Tope, T.; Voirin, E.; Yang, T.

    2014-07-01

    The Liquid Argon Purity Demonstrator was an R&D test stand designed to determine if electron drift lifetimes adequate for large neutrino detectors could be achieved without first evacuating the cryostat. We describe here the cryogenic system, its operations, and the apparatus used to determine the contaminant levels in the argon and to measure the electron drift lifetime. The liquid purity obtained by this system was facilitated by a gaseous argon purge. Additionally, gaseous impurities from the ullage were prevented from entering the liquid at the gas-liquid interface by condensing the gas and filtering the resulting liquid before returning to the cryostat. The measured electron drift lifetime in this test was greater than 6 ms, sustained over several periods of many weeks. Measurements of the temperature profile in the argon, to assess convective flow and boiling, were also made and are compared to simulation.

  2. Tetragonal Red and Yellow HgI2-CdI2 Crystals for X- and Gamma-ray Solid-State Detectors Directionally Solidified Under Argon Pressure of 20 atm

    SciTech Connect

    Cummings, T.; Marin, C.; Ostrogorsky, A. G.; Burger, A.; Bliss, Mary

    2006-12-29

    Ternary Hg1-xCdxI2 (0argon pressure of ~ 20 atm. For 0 < x < 0.15, the crystals appear red (the same color as pure HgI2). For x>0.15 the crystals are yellow. In the full compositional range 0detectors.

  3. Work at FNAL to achieve long electron drift lifetime in liquid argon

    SciTech Connect

    Finley, D.; Jaskierny, W.; Kendziora, C.; Krider, J.; Pordes, S.; Rapidis, P.A.; Tope, T.; /Fermilab

    2006-10-01

    This note records some of the work done between July 2005 and July 2006 to achieve long (many milliseconds) electron drift lifetimes in liquid argon at Fermilab. The work is part of a process to develop some experience at Fermilab with the technology required to construct a large liquid argon TPC. This technology has been largely developed by the ICARUS collaboration in Europe and this process can be seen as technology transfer. The capability to produce liquid argon in which electrons have drift lifetimes of several milliseconds is crucial to a successful device. Liquid argon calorimeters have been successfully operated at Fermilab; their electro-negative contaminants are at the level of 10{sup -7} while the TPC we are considering requires a contamination level at the level of 10{sup -11}, tens of parts per trillion (ppt). As well as demonstrating the ability to produce liquid argon at this level of purity, the work is part of a program to test the effect on the electron drift time of candidate materials for the construction of a TPC in liquid argon.

  4. Transaction Processing Performance Council (TPC): State of the Council 2010

    NASA Astrophysics Data System (ADS)

    Nambiar, Raghunath; Wakou, Nicholas; Carman, Forrest; Majdalany, Michael

    The Transaction Processing Performance Council (TPC) is a non-profit corporation founded to define transaction processing and database benchmarks and to disseminate objective, verifiable performance data to the industry. Established in August 1988, the TPC has been integral in shaping the landscape of modern transaction processing and database benchmarks over the past twenty-two years. This paper provides an overview of the TPC's existing benchmark standards and specifications, introduces two new TPC benchmarks under development, and examines the TPC's active involvement in the early creation of additional future benchmarks.

  5. HARPO: beam characterization of a TPC for gamma-ray polarimetry and high angular-resolution astronomy in the MeV-GeV range

    NASA Astrophysics Data System (ADS)

    Wang, Shaobo; Bernard, Denis; Bruel, Philippe; Frotin, Mickael; Geerebaert, Yannick; Giebels, Berrie; Gros, Philippe; Horan, Deirdre; Louzir, Marc; Poilleux, Patrick; Semeniouk, Igor; Attié, David; Calvet, Denis; Colas, Paul; Delbart, Alain; Sizun, Patrick; Götz, Diego; Amano, Sho; Kotaka, Takuya; Hashimoto, Satoshi; Minamiyama, Yasuhito; Takemoto, Akinori; Yamaguchi, Masashi; Miyamoto, Shuji; Daté, Schin; Ohkuma, Haruo

    2015-11-01

    A time projection chamber (TPC) can be used to measure the polarization of gamma rays with excellent angular precision and sensitivity in the MeV-GeV energy range through the conversion of photons to e+e- pairs. The Hermetic ARgon POlarimeter (HARPO) prototype was built to demonstrate this concept. It was recently tested in the polarized photon beam at the NewSUBARU facility in Japan. We present this data-taking run, which demonstrated the excellent performance of the HARPO TPC.

  6. Simulation of double beta decay in the ''SeXe'' TPC

    NASA Astrophysics Data System (ADS)

    Mauger, F.

    2007-04-01

    In 2004, the NEMO collaboration has started some preliminary studies for a next-generation double beta decay experiment: SuperNEMO. The possibility to use a large gaseous TPC has been investigated using simulation and extrapolation of former experiments. In this talk, I report on the reasons why such techniques have not been selected in 2004 and led the NEMO collaboration to reuse the techniques implemented within the NEMO3 detector.

  7. 3D reconstruction of nuclear reactions using GEM TPC with planar readout

    SciTech Connect

    Bihałowicz, Jan Stefan

    2015-02-24

    The research program of the Extreme Light Infrastructure – Nuclear Physics (ELI-NP) laboratory under construction in Magurele, Romania facilities the need of developing a gaseous active-target detector providing 3D reconstruction of charged products of nuclear reactions induced by gamma beam. The monoenergetic, high-energy (E{sub γ} > 19 MeV) gamma beam of intensity 10{sup 13}γ/s allows studying nuclear reactions in astrophysics. A Time Projection Chamber with crossed strip readout (eTPC) is proposed as one of the imaging detectors. The special feature of the readout electrode structure is a 2D reconstruction based on the information read out simultaneously from three arrays of strips that form virtual pixels. It is expected to reach similar spatial resolution as for pixel readout at largely reduced cost of electronics. The paper presents the current progress and first results of the small scale prototype TPC which is a one of implementation steps towards eTPC detector proposed in the Technical Design Report of Charged Particles Detection at ELI-NP.

  8. Strange particle measurements from the EOS TPC

    SciTech Connect

    Justice, M.

    1995-02-01

    A high statistics sample of {Lambda}`s produced in 2 GeV/nucleon {sup 5}8Ni + {sup nat}Cu collisions has been obtained with the EOS Time Projection Chamber at the Bevalac. The coverage of the EOS TPC is essentially 100% for y > y{sub cm} and extends down to P{sub T} = 0 where interesting effects such as collective radial expansion may be important. In addition, the detection of a majority of the charged particles in the TPC, along with the presence of directed flow for protons and heavier fragments at this beam energy, allows for the correlation of A production with respect to the event reaction plane. Our preliminary analysis indicates the first observation of a sidewards flow signature for A`s. Comparisons with the cascade code ARC are made.

  9. Recent developments on the star detector system at RHIC

    NASA Astrophysics Data System (ADS)

    Wieman, H.; Adams, D. L.; Added, N.; Agakishiev, H.; Akimenko, S. A.; Aluyshin, A.; Aluyshin, M.; Amelin, N.; Anderson, B.; Anderson, G.; Aprahamian, A.; Arestov, Y. I.; Aslanyan, P.; Avdeichikov, V.; Averichev, G.; Bacher, A.; Badalian, R.; Baldwin, A.; Barish, K.; Batourine, V.; Belikov, N. L.; Bellwied, R.; Belousov, V.; Bennett, S.; Best, D.; Bichsel, H.; Bielecki, J.; Bieser, F.; Biswas, N. N.; Bland, L.; Blyth, C.; Bonner, B. E.; Bossingham, R.; Brady, F. P.; Braithwaite, W.; Brown, C.; Brown, R. L.; Budilov, V.; Caines, H.; Cameron, J.; Carlin, N.; Carroll, J.; Cebra, D.; Chalyguine, A.; Chance, J.; Chen, W.; Chernenko, S.; Cherney, M.; Chikanian, A.; Chrin, J.; Christie, W.; Chujko, B.; Consiglio, C.; Cooper, G.; Cormier, T. M.; Cramer, J.; Crawford, H. J.; Davidenko, A. M.; Das, A.; Dawson, J. W.; Dereschikov, A. A.; Deweerd, A.; Didenko, L.; Dominik, W.; Draper, J. E.; Duck, I.; Edwards, W. R.; Eckardt, V.; Emelianov, V.; Engelage, J. M.; Eppley, G.; Eremeev, R.; Erin, V.; Etkin, A.; Fachini, P.; Fadeev, N.; Faine, V.; Fateev, O.; Feshchenko, A.; Fisyak, Y.; Foley, K. J.; Ford, C. W., Jr.; Gagunashvili, N.; Garg, U.; Gavrichtchouk, O.; Gazdzicki, M.; Ghazikhanian, V.; Gilkes, M.; Grachov, A.; Greiner, D.; Greiner, L.; Grigoriev, V.; Guarino, V. J.; Gushin, E.; Haberichter, W. N.; Hackenburg, R. W.; Hall, J.; Hallman, T. J.; Harris, J.; Heppelmann, S.; Hill, D. A.; Hill, N.; Hirsch, A.; Hjort, E.; Hoffmann, J.; Huang, H.; Humanic, T.; Igo, G. J.; Ioukaev, A.; Jacobs, P.; Jacobs, W.; Jared, R.; Jensen, P.; Jones, P.; Judd, E.; Kadija, K.; Kaplan, M.; Kaplin, V.; Karakash, A.; Karev, A.; Karol, P. J.; Kasprzyk, T.; Keane, D.; Kinder-Geiger, K.; Klein, S.; Kolobashkina, L.; Kolomyichenko, A.; Komisarcík, K.; Konstantinov, A.; Kossarev, I.; Kotchenda, L.; Kotov, I.; Kouzmine, N.; Kovalenko, A.; Kramer, M.; Kravtsov, P.; Krivokhizhin, V.; Kunde, G.; Kutuev, R.; Kuznetsov, A.; Kwiatkowski, K.; Ladygin, V.; Lasiuk, B.; Lebedev, A.; Lecompte, T.; Levine, M. J.; Li, Q.; Lisa, M.; Ljubicic, A.; Llope, W.; Longacre, R. S.; Love, W. A.; Lynn, D.; Madansky, L.; Majka, R.; Margetis, S.; Marx, J.; Matheus, R.; Matis, H. S.; Matulenko, Y.; Matushevsky, E.; McShane, T. S.; Medved, K.; Mekhdiev, R.; Meschanin, A.; Middlekamp, P.; Miller, B.; Milosevich, Z.; Minaev, N.; Mitchell, J.; Mitsyn, V.; Moore, F.; Muresan, L.; Muresan, R.; Musulmanbekov, J.; Mutchler, G. S.; Mysnick, A.; Nann, H.; Nelson, J.; Nevski, P.; Nikitin, V.; Nikonov, E.; Nomokonov, P.; Nurushev, S. B.; Nystrand, J.; Odintsov, V.; Odyniec, G.; Ogawa, A.; Ogilivie, C.; Olson, D.; Oltchak, A.; Ososkov, G.; Ott, G.; Paic, G.; Pandey, S.; Panebratsev, Y.; Panitkin, S.; Pavlinov, A.; Pavluk, A.; Pawlak, T.; Pentia, M.; Peryt, W.; Peshekhonov, D.; Peshekhonov, V.; Pilipenko, D.; Piskunov, N.; Platner, E.; Pluta, J.; Porile, N.; Poskanzer, A. M.; Price, L.; Prindle, D.; Protrebenikova, E.; Pruneau, C.; Rai, G.; Ray, L.; Razin, S.; Renfordt, R. E.; Ridiger, A.; Riley, P.; Rinckel, T.; Riso, J.; Ritter, H.-G.; Roberts, J. B.; Rhrich, D.; Rollefson, A.; Romero, J. L.; Roufanov, I.; Runco, M.; Rykov, V.; Sakrejda, I.; Sandweiss, J.; Saulys, A. C.; Savin, I.; Schafer, E.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Schroeder, L. S.; Schulz, M.; Sedlmeir, J.; Seger, J.; Seliverstov, D.; Seyboth, P.; Shabunov, A.; Shafranov, M.; Shafranova, M.; Shalnov, A.; Shestermanov, K.; Shimanskiy, S.; Skoro, G.; Slaughter, J.; Slavin, N.; Smirnoff, N.; Smirnov, G.; Smykov, L.; Soloviev, L.; Somov, S.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; Stephenson, E.; Stock, R.; Stone, N.; Strikhanov, M.; Stringfellow, B.; Strbele, H.; Strokovsky, E.; Sugarbaker, E.; Sustich, A.; Symons, T. J.; Szanto, E.; Szanto de Toledo, A.; Thomas, J.; Tikhonov, V.; Trainor, T.; Trentalange, S.; Tokarev, M.; Trofimov, V.; Tsay, O.; Tull, C.; Turner, K.; Tustonic, T.; Ullrich, T.; Underwood, D. G.; Usubov, Z.; Vandermolen, S.; Vanyashin, A.; Vasendina, V.; Vasiliev, A. N.; Vasiliev, V.; Vigdor, S.; Viola, V.; Vorozhtsov, S.; Vranic, D.; Wang, F.; Ward, H.; Watson, J.; Weerasundara, D.; Wells, R.; Wenaus, T.; Westfall, G.; Whitten, C., Jr.; Wilson, K.; Wissink, S.; Wold, D.; Wood, L.; Xu, N.; Yepes, P.; Yokosawa, A.; Yurevich, V.; Zanevsky, Y.; Zhang, W.; Zhidkov, N.; Zhiltsov, V.; Zoulkarneev, R.

    1998-08-01

    A progress report is given for the various components of the STAR detector system. We report on the recent developments in the detector proto-typing and construction, with an emphasis on the main TPC, recent TPC cosmic ray testing and shipping to Brookhaven National Laboratory.

  10. Bustling argon: biological effect

    PubMed Central

    2013-01-01

    Argon is a noble gas in group 18 of the periodic table. Certificated to exist in air atmosphere merely one century ago, discovery of argon shows interesting stories of researching and exploring. It was assumed to have no chemical activity. However, argon indeed present its biological effect on mammals. Narcotic effect of argon in diving operation and neur-protective function of argon in cerebral injury demonstrate that argon has crucial effect and be concentrated on is necessary. Furthermore, consider to be harmless to human, argon clinical application in therapy would be another option. PMID:24088583

  11. The CAPTAIN liquid argon neutrino experiment

    SciTech Connect

    Liu, Qiuguang

    2015-01-01

    The CAPTAIN liquid argon experiment is designed to make measurements of scientific importance to long-baseline neutrino physics and physics topics that will be explored by large underground detectors. The experiment employs two detectors – a primary detector with approximately 10-ton of liquid argon that will be deployed at different facilities for physics measurements and a prototype detector with 2-ton of liquid argon for configuration testing. The physics programs for CAPTAIN include measuring neutron interactions at Los Alamos Neutron Science Center, measuring neutrino interactions in medium energy regime (1.5–5 GeV) at Fermilab's NuMI beam, and measuring neutrino interactions in low energy regime (< 50 MeV) at stopped pion sources for supernova neutrino studies.

  12. The CAPTAIN liquid argon neutrino experiment

    DOE PAGESBeta

    Liu, Qiuguang

    2015-01-01

    The CAPTAIN liquid argon experiment is designed to make measurements of scientific importance to long-baseline neutrino physics and physics topics that will be explored by large underground detectors. The experiment employs two detectors – a primary detector with approximately 10-ton of liquid argon that will be deployed at different facilities for physics measurements and a prototype detector with 2-ton of liquid argon for configuration testing. The physics programs for CAPTAIN include measuring neutron interactions at Los Alamos Neutron Science Center, measuring neutrino interactions in medium energy regime (1.5–5 GeV) at Fermilab's NuMI beam, and measuring neutrino interactions in low energymore » regime (< 50 MeV) at stopped pion sources for supernova neutrino studies.« less

  13. An optical readout TPC (O-TPC) for studies in nuclear astrophysics with gamma-ray beams at HIγS1

    NASA Astrophysics Data System (ADS)

    Gai, M.; Ahmed, M. W.; Stave, S. C.; Zimmerman, W. R.; Breskin, A.; Bromberger, B.; Chechik, R.; Dangendorf, V.; Delbar, Th; France, R. H., III; Henshaw, S. S.; Kading, T. J.; Martel, P. P.; McDonald, J. E. R.; Seo, P.-N.; Tittelmeier, K.; Weller, H. R.; Young, A. H.

    2010-12-01

    We report on the construction, tests, calibrations and commissioning of an Optical Readout Time Projection Chamber (O-TPC) detector operating with a CO2(80%) + N2(20%) gas mixture at 100 and 150 Torr. It was designed to measure the cross sections of several key nuclear reactions involved in stellar evolution. In particular, a study of the rate of formation of oxygen and carbon during the process of helium burning will be performed by exposing the chamber gas to intense nearly mono-energetic gamma-ray beams at the High Intensity Gamma Source (HIγS) facility. The O-TPC has a sensitive target-drift volume of 30x30x21 cm3. Ionization electrons drift towards a double parallel-grid avalanche multiplier, yielding charge multiplication and light emission. Avalanche-induced photons from N2 emission are collected, intensified and recorded with a Charge Coupled Device (CCD) camera, providing two-dimensional track images. The event's time projection (third coordinate) and the deposited energy are recorded by photomultipliers and by the TPC charge-signal, respectively. A dedicated VME-based data acquisition system and associated data analysis tools were developed to record and analyze these data. The O-TPC has been tested and calibrated with 3.183 MeV alpha-particles emitted by a 148Gd source placed within its volume with a measured energy resolution of 3.0%. Tracks of alpha and 12C particles from the dissociation of 16O and of three alpha-particles from the dissociation of 12C have been measured during initial in-beam test experiments performed at the HIγS facility at Duke University. The full detection system and its performance are described and the results of the preliminary in-beam test experiments are reported.

  14. The Origins and Evolution of the Time Projection Chamber (TPC) Idea

    SciTech Connect

    Nygren, David

    2012-09-19

    In February 1974, I conceived an idea for a tracking detector with only one spatial projection, thereby eliminating ambiguities that occur in conventional detector systems based on wires. I called it the “Time Projection Chamber”, or TPC, a name that has stuck even though the concept has evolved considerably over the following decades. I will recount the history leading to its conception and development in that now distant epoch, and will attempt to show why this is an interesting and instructive story and how the idea may continue to extend scientific reach in the coming era.

  15. Directional Neutron Detection and TPC Developments and LLNL

    SciTech Connect

    Heffner, M

    2009-03-24

    LLNL is involved with a number of TPC projects spanning basic science to homeland security. This talk outlines the TPC work at LLNL and specifically focuses on the neutron TPC. A number of TPC projects are now underway at Lawrence Livermore National Laboratory (LLNL) and there is currently a ramp up in the infrastructure both in equipment and people to support these efforts. In place are high pressure vessels for xenon studies up to 50bar, larger vessels up to 100 litters at 10bar, clean room facilities, extensive electronics development, dedicated lab space and a assortment of radioactive sources.

  16. How to Advance TPC Benchmarks with Dependability Aspects

    NASA Astrophysics Data System (ADS)

    Almeida, Raquel; Poess, Meikel; Nambiar, Raghunath; Patil, Indira; Vieira, Marco

    Transactional systems are the core of the information systems of most organizations. Although there is general acknowledgement that failures in these systems often entail significant impact both on the proceeds and reputation of companies, the benchmarks developed and managed by the Transaction Processing Performance Council (TPC) still maintain their focus on reporting bare performance. Each TPC benchmark has to pass a list of dependability-related tests (to verify ACID properties), but not all benchmarks require measuring their performances. While TPC-E measures the recovery time of some system failures, TPC-H and TPC-C only require functional correctness of such recovery. Consequently, systems used in TPC benchmarks are tuned mostly for performance. In this paper we argue that nowadays systems should be tuned for a more comprehensive suite of dependability tests, and that a dependability metric should be part of TPC benchmark publications. The paper discusses WHY and HOW this can be achieved. Two approaches are introduced and discussed: augmenting each TPC benchmark in a customized way, by extending each specification individually; and pursuing a more unified approach, defining a generic specification that could be adjoined to any TPC benchmark.

  17. Design and performance of TOPAZ TPC-trigger

    SciTech Connect

    Enomoto, R.; Tsukada, K.; Ujiie, N.; Shirahashi, A.

    1988-02-01

    The Time Projection Chamber (TPC) is widely used in the high energy physics experiment. The authors developed the new track finding algorithm by using the TOPAZ-TPC. The logic not only finds the number of tracks, but also calculates their vertex positions. It also takes care of the sector boundary crossing tracks. The proto-type TPC-Trigger has been tested at the in-beam experiment and has shown good performance. The authors achieved the vertex resolution of less than 10cm (r.m.s.) in the beam direction. The improved TPC-Trigger system is being used in October 1987 beam run.

  18. Muon tomography of rock density using Micromegas-TPC telescope

    NASA Astrophysics Data System (ADS)

    Hivert, Fanny; Busto, José; Gaffet, Stéphane; Ernenwein, Jean-Pierre; Brunner, Jurgen; Salin, Pierre; Decitre, Jean-Baptiste; Lázaro Roche, Ignacio; Martin, Xavier

    2014-05-01

    The knowledge of the subsurface properties is essentially obtained by geophysical methods, e.g., seismic imaging, electric prospection or gravimetry. The current work is based on a recently developed method to investigate in situ the density of rocks using a measurement of the muon flux, whose attenuation depends on the quantity of matter the particles travel through and hence on the rock density and thickness. The present project (T2DM2) aims at performing underground muon flux measurements in order to characterize spatial and temporal rock massif density variations above the LSBB underground research facility in Rustrel (France). The muon flux will be measured with a new muon telescope device using Micromegas-Time Projection Chamber (TPC) detectors. The first step of the work presented covers the muon flux simulation based on the Gaisser model (Gaisser T., 1990), for the muon flux at the ground level, and on the MUSIC code (Kudryavtsev V. A., 2008) for the propagation of muons through the rock. The results show that the muon flux distortion caused by density variations is enough significant to be observed at 500 m depth for measurement times of about one month. This time-scale is compatible with the duration of the water transfer processes within the unsaturated Karst zone where LSBB is located. The work now focuses on the optimization of the detector layout along the LSBB galleries in order to achieve the best sensitivity.

  19. Future prospects of the TPC idea

    SciTech Connect

    Nygren, D.R.

    1980-07-01

    General aspects affecting TPC size, readout plane characteristics and operation in the LEP environment are presented, with the general conclusion that modest improvements relative to PEP-4 can be realized in several areas. The problem of positive ion reduction is discussed according to two qualitatively new operating modes, asynchronous and synchronous gating. Either gating mode appears to offer a means to eliminate almost completely the ion return flux. Some speculative ideas involving 3-component gas mixtures, low-mass components and parallel plane geometry are presented as future possibilities.

  20. A study of the trace 39Ar content in argon from deep underground sources

    NASA Astrophysics Data System (ADS)

    Xu, J.; Calaprice, F.; Galbiati, C.; Goretti, A.; Guray, G.; Hohman, T.; Holtz, D.; Ianni, An.; Laubenstein, M.; Loer, B.; Love, C.; Martoff, C. J.; Montanari, D.; Mukhopadhyay, S.; Nelson, A.; Rountree, S. D.; Vogelaar, R. B.; Wright, A.

    2015-06-01

    The discovery of argon from deep underground sources with significantly less 39Ar than atmospheric argon was an important step in the development of direct dark matter detection experiments using argon as the active target. We report on the design and operation of a low-background single-phase liquid argon detector that was built to study the 39Ar content of this underground argon. Underground argon from the Kinder Morgan CO2 plant in Cortez, Colorado was determined to have less than 0.65% of the 39Ar activity in atmospheric argon, or 6.6 mBq/kg specific 39Ar activity.

  1. Team Primacy Concept (TPC) Based Employee Evaluation and Job Performance

    ERIC Educational Resources Information Center

    Muniute, Eivina I.; Alfred, Mary V.

    2007-01-01

    This qualitative study explored how employees learn from Team Primacy Concept (TPC) based employee evaluation and how they use the feedback in performing their jobs. TPC based evaluation is a form of multirater evaluation, during which the employee's performance is discussed by one's peers in a face-to-face team setting. The study used Kolb's…

  2. Data Reduction Processes Using FPGA for MicroBooNE Liquid Argon Time Projection Chamber

    SciTech Connect

    Wu, Jinyuan

    2010-05-26

    MicroBooNE is a liquid Argon time projection chamber to be built at Fermilab for an accelerator-based neutrino physics experiment and as part of the R&D strategy for a large liquid argon detector at DUSEL. The waveforms of the {approx}9000 sense wires in the chamber are continuously digitized at 2 M samples/s - which results in a large volume of data coming off the TPC. We have developed a lossless data reduction scheme based on Huffman Coding and have tested the scheme on cosmic ray data taken from a small liquid Argon time projection chamber, the BO detector. For sense wire waveforms produced by cosmic ray tracks, the Huffman Coding scheme compresses the data by a factor of approximately 10. The compressed data can be fully recovered back to the original data since the compression is lossless. In addition to accelerator neutrino data, which comes with small duty cycle in sync with the accelerator beam spill, continuous digitized waveforms are to be temporarily stored in the MicroBooNE data-acquisition system for about an hour, long enough for an external alert from possible supernova events. Another scheme, Dynamic Decimation, has been developed to compress further the potential supernova data so that the storage can be implemented within a reasonable budget. In the Dynamic Decimation scheme, data are sampled at the full sampling rate in the regions-of-interest (ROI) containing waveforms of track-hits and are decimated down to lower sampling rate outside the ROI. Note that unlike in typical zerosuppression schemes, in Dynamic Decimation, the data in the pedestal region are not thrown away but kept at a lower sampling rate. An additional factor of 10 compression ratio is achieved using the Dynamic Decimation scheme on the BO detector data, making a total compression rate of approximate 100 when the Dynamic Decimation and the Huffman Coding functional blocks are cascaded. Both of the blocks are compiled in low-cost FPGA and their silicon resource usages are low.

  3. Detectors

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan; Allander, Krag

    2002-01-01

    The apparatus and method provide techniques through which both alpha and beta emission determinations can be made simultaneously using a simple detector structure. The technique uses a beta detector covered in an electrically conducting material, the electrically conducting material discharging ions generated by alpha emissions, and as a consequence providing a measure of those alpha emissions. The technique also offers improved mountings for alpha detectors and other forms of detectors against vibration and the consequential effects vibration has on measurement accuracy.

  4. TPC in γ-ray astronomy above pair-creation threshold

    NASA Astrophysics Data System (ADS)

    Bernard, D.

    2013-02-01

    We examine the performance of a TPC as a γ-ray telescope above the pair-creation threshold. The contributions to the photon angular resolution are studied and their dependence on energy is obtained. The effective area per detector unit mass for such a thin detector is the conversion mass attenuation coefficient. The differential sensitivity for the detection of a point-like source is then derived. Finally, the measurement of track momentum from deflections due to multiple scattering is optimized.These analytical results are exemplified numerically for a few sets of detector parameters. TPCs show an impressive improvement in sensitivity with respect to existing pair-creation-based telescopes in the [MeV-GeV] energy range, even with the modest detector parameters of this study. In addition, gas TPCs allow an improvement in angular resolution of about one order of magnitude.

  5. Measurement of Gain and Drift Velocity of the Prototype AT-TPC

    NASA Astrophysics Data System (ADS)

    Wolff, Michael; Soussi Tanani, Rim; Cortesi, Marco; Mittig, Wolfgang; Fritsch, Adam

    2015-10-01

    The Prototype Active-Target Time-Projection Chamber (PAT-TPC) at the National Superconducting Cyclotron Laboratory (NSCL) is used to study reactions induced by radioactive ions in a detector gas that serves both as the target and tracking medium. It employs gaseous amplification of the primary electrons that drift to the amplification gap to track and measure charged particles traversing the active gaseous volume of the chamber. A setup consisting of two THGEMs (Thick Gas Electron Multipliers) stacked on a Micromegas (Micro mesh gas amplifier) device was tested in the PAT-TPC in June and July of 2015. A 337-Si laser, a 252Cf spontaneous fission source, and an α source were used to ionize target gas molecules in the active volume. Electron drift velocity was measured as a function of the electric field held across the volume and for varying gas compositions ranging from pure H2 to a 95:5 H2:C4H10 mixture. Analysis of the tests provided information on conditions for optimal gain for the setup used in an August 2015 PAT-TPC experiment at the University of Notre Dame's Nuclear Science Laboratory and other future experiments. Data and results will be presented. Funded in part thanks to College of Wooster and NSF Grant Nos. PHy-1430152, MRI09-23087, and PHY09-69456.

  6. Recent results from the PEP4-TPC on quark fragmentation

    SciTech Connect

    Hofmann, W.

    1983-11-12

    The physics goals for the PEP-4/PEP-9 experiment concentrate on two areas: the fragmentation properties of quarks and gluons produced in e+e- annihilation, and the investigation of hadron production in 2-photon collisions. Only the first of these topics is addressed. Despite the many successes of QCD in the description of deep inelastic reactions, the basic fragmentation process of quarks and gluons is not very well understood. This lack of knowledge has been shown to jeopardize precise test of QCD, such as the accurate determination of the strong coupling constant. With its ability to disentangle complex hadronic events and to identify most of the final state particles, the TPC allows new and more sensitive tests of fragmentation models. A brief description of the detector is given and particle identification by ionization energy loss is described. Next, the inclusive production of stable hadrons and of resonances is discussed, and limits on the inclusive production of fractional charged particles are given. A new analysis of long-range correlations in e+e- annihilation is given.

  7. The ATLAS Liquid Argon Electromagnetic Calorimeter

    SciTech Connect

    Carminati, L.

    2005-10-12

    The construction of the ATLAS Liquid Argon Electromagnetic calorimeter has been completed and commissioning is in progress. After a brief description of the detector layout, readout electronics and calibration, a review of the present status of the integration and the detector qualification is reported. Finally a selection of performance results obtained during several test beams will be presented with particular attention to linearity, uniformity, position reconstruction and {gamma}/{pi}0 separation.

  8. The design and implementation of TPC encoder and decoder

    NASA Astrophysics Data System (ADS)

    Xiang, L. J.; Wang, Z. B.; Yuan, J. B.; Zheng, L. H.

    2016-02-01

    Based on the analysis and simulation of TPC codec principle and iteration decoding algorithm based on Chase 2, the design and implementation methods of TPC encoder and decoder are presented in this paper. In particular, circuit design and implementation flow of soft-input soft-output modified method in decoder algorithm and iteration decoding are analyzed. Aiming at (64,57,4) TPC, when the iteration times is 3 and the uncertain position number is 3, simulation and implementation results show that at least 6.8dB encoding gain can be obtained under the condition of BER=10-6

  9. Simulations of Charged-Current Supernova νe Events in a Liquid Argon Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Gardiner, Steven; Grant, Christopher; Pantic, Emilija; Svoboda, Robert

    2016-03-01

    Although it is still in its infancy, the study of supernova neutrinos has proven to be a fertile topic for fundamental science. A mere two dozen events recorded from supernova 1987A, the only supernova neutrino source observed so far, have led to numerous publications on a wide variety of topics. This bountiful scientific harvest has prompted the neutrino physics community to prepare to make more detailed observations of the neutrinos that will be produced in the next nearby supernova. Because of their unique νe sensitivity, liquid argon time projection chamber (LArTPC) experiments such as DUNE (Deep Underground Neutrino Experiment) have the potential to make valuable contributions to this detection effort. To better understand the expected SN νe signal in a LArTPC, we have developed a Monte Carlo event generator called MARLEY (Model of Argon Reaction Low-Energy Yields) for charged-current νe reactions on argon. By combining MARLEY with LArSoft, a LArTPC simulation package, we have obtained the most detailed predictions currently available for the response of a LArTPC to supernova νe. We will discuss the implications of these results for the design and operation of LArTPCs sensitive to SN neutrinos.

  10. Behavior of TPC's in a high particle flux environment

    SciTech Connect

    Etkin, A.; Eisemann, S.E.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C. ); Lindenbaum, S.J. City Coll., New York, NY ); Chan, C.S.; Kramer, M.A.; Zhao, K.H.; Zhu, Y. ); Hallman, T.J.; Madansky, L

    1991-12-13

    TPC's (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchrotron) were exposed to fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to find if such high fluxes cause gain changes or distortions of the electric field. Initial results of these and other tests are presented and the consequences for the RHIC (Relativistic Heavy Ion Collider) TPC-based experiments are discussed.

  11. Fast TPC Online Tracking on GPUs and Asynchronous Data Processing in the ALICE HLT to facilitate Online Calibration

    NASA Astrophysics Data System (ADS)

    Rohr, David; Gorbunov, Sergey; Krzewicki, Mikolaj; Breitner, Timo; Kretz, Matthias; Lindenstruth, Volker

    2015-12-01

    ALICE (A Large Heavy Ion Experiment) is one of the four major experiments at the Large Hadron Collider (LHC) at CERN, which is today the most powerful particle accelerator worldwide. The High Level Trigger (HLT) is an online compute farm of about 200 nodes, which reconstructs events measured by the ALICE detector in real-time. The HLT uses a custom online data-transport framework to distribute data and workload among the compute nodes. ALICE employs several calibration-sensitive subdetectors, e.g. the TPC (Time Projection Chamber). For a precise reconstruction, the HLT has to perform the calibration online. Online- calibration can make certain Offline calibration steps obsolete and can thus speed up Offline analysis. Looking forward to ALICE Run III starting in 2020, online calibration becomes a necessity. The main detector used for track reconstruction is the TPC. Reconstructing the trajectories in the TPC is the most compute-intense step during event reconstruction. Therefore, a fast tracking implementation is of great importance. Reconstructed TPC tracks build the basis for the calibration making a fast online-tracking mandatory. We present several components developed for the ALICE High Level Trigger to perform fast event reconstruction and to provide features required for online calibration. As first topic, we present our TPC tracker, which employs GPUs to speed up the processing, and which bases on a Cellular Automaton and on the Kalman filter. Our TPC tracking algorithm has been successfully used in 2011 and 2012 in the lead-lead and the proton-lead runs. We have improved it to leverage features of newer GPUs and we have ported it to support OpenCL, CUDA, and CPUs with a single common source code. This makes us vendor independent. As second topic, we present framework extensions required for online calibration. The extensions, however, are generic and can be used for other purposes as well. We have extended the framework to support asynchronous compute

  12. Drift parameters optimization of a TPC polarimeter: a simulation study

    NASA Astrophysics Data System (ADS)

    Rakhee, K.; Radhakrishna, V.; Koushal, V.; Baishali, G.; Vinodkumar, A. M.

    2015-06-01

    Time Projection Chamber (TPC) based X-ray polarimeters using Gas Electron Multiplier (GEM) are currently being developed to make sensitive measurement of polarization in 2-10 keV energy range. The emission direction of the photoelectron ejected via photoelectric effect carries the information of the polarization of the incident X-ray photon. Performance of a gas based polarimeter is affected by the operating drift parameters such as gas pressure, drift field and drift-gap. We present simulation studies carried out in order to understand the effect of these operating parameters on the modulation factor of a TPC polarimeter. Models of Garfield are used to study photoelectron interaction in gas and drift of electron cloud towards GEM. Our study is aimed at achieving higher modulation factors by optimizing drift parameters. Study has shown that Ne/DME (50/50) at lower pressure and drift field can lead to desired performance of a TPC polarimeter.

  13. Lunar exospheric argon modeling

    NASA Astrophysics Data System (ADS)

    Grava, Cesare; Chaufray, J.-Y.; Retherford, K. D.; Gladstone, G. R.; Greathouse, T. K.; Hurley, D. M.; Hodges, R. R.; Bayless, A. J.; Cook, J. C.; Stern, S. A.

    2015-07-01

    Argon is one of the few known constituents of the lunar exosphere. The surface-based mass spectrometer Lunar Atmosphere Composition Experiment (LACE) deployed during the Apollo 17 mission first detected argon, and its study is among the subjects of the Lunar Reconnaissance Orbiter (LRO) Lyman Alpha Mapping Project (LAMP) and Lunar Atmospheric and Dust Environment Explorer (LADEE) mission investigations. We performed a detailed Monte Carlo simulation of neutral atomic argon that we use to better understand its transport and storage across the lunar surface. We took into account several loss processes: ionization by solar photons, charge-exchange with solar protons, and cold trapping as computed by recent LRO/Lunar Orbiter Laser Altimeter (LOLA) mapping of Permanently Shaded Regions (PSRs). Recycling of photo-ions and solar radiation acceleration are also considered. We report that (i) contrary to previous assumptions, charge exchange is a loss process as efficient as photo-ionization, (ii) the PSR cold-trapping flux is comparable to the ionization flux (photo-ionization and charge-exchange), and (iii) solar radiation pressure has negligible effect on the argon density, as expected. We determine that the release of 2.6 × 1028 atoms on top of a pre-existing argon exosphere is required to explain the maximum amount of argon measured by LACE. The total number of atoms (1.0 × 1029) corresponds to ∼6700 kg of argon, 30% of which (∼1900 kg) may be stored in the cold traps after 120 days in the absence of space weathering processes. The required population is consistent with the amount of argon that can be released during a High Frequency Teleseismic (HFT) Event, i.e. a big, rare and localized moonquake, although we show that LACE could not distinguish between a localized and a global event. The density of argon measured at the time of LACE appears to have originated from no less than four such episodic events. Finally, we show that the extent of the PSRs that trap

  14. Herman Feshbach Prize in Theoretical Nuclear Physics Xiangdong Ji, University of Maryland PandaX-III: high-pressure gas TPC for Xe136 neutrinoless double beta decay at CJPL

    NASA Astrophysics Data System (ADS)

    Ji, Xiangdong; PandaX-III Collaboration

    2016-03-01

    The PandaX-III in China's Jinping Underground Lab is a new neutrinoless double beta decay experiment using Xe136 high-pressure gas TPC. The first phase of the experiment uses a 4 m3 gas detector with symmetric Micromegas charge readout planes. The gas TPC allows full reconstruction of the event topology, capable of distinguishing the two electron events from gamma background with high confidence level. The energy resolution can reach about 3% FWHM at the beta decay Q-value. The detector construction and the experimental lab is currently under active development. In this talk, the current status and future plan are reported.

  15. Load on Trough Bellows Following an Argon Spill

    SciTech Connect

    Chess, K.; /Fermilab

    1988-07-12

    In the case of a gross argon spill from the DO detector, the liquid argon is caught in three plenums. These plenums are to be connected by bellows to make a horizontal trough open at one end for removing the argon. The design of these bellows is dependent on the maximum argon load they must carry. Bellows to connect the three argon-catching plenums in the DO detector must be able to carry at least 92 lbs of argon when closed and 231 lbs when open, plus the load due to argon in the convolutions. Examples of such loads and the method for their calculations are contained in the Discussion. It should be noted that a set of assumptions was used in these calculations. First, we considered a uniform channel and uniform flow. Second, we used a value for Manning's n meant for a similar, but not exactly the same, case. Finally, we were forced to define an average depth, d, to be used to state the hydraulic radius, R, and area of flow, A. These facts may warrant consideration in future calculations.

  16. Recent developments on the STAR detector system at RHIC

    SciTech Connect

    Wieman, H.; Adams, D.L.; Added, N.

    1997-12-01

    The STAR detector system is designed to provide tracking, momentum analysis and particle identification for many of the mid-rapidity charged particles produced in collisions at the RHIC collider. A silicon vertex detector (SVT) provides three layers of tracking near the interaction point. This is followed by the main time projection chamber (TPC), which continues tracking out to 200 cm radial distance from the interaction region. The detector design also includes an electromagnetic calorimeter, various trigger detectors, and radial TPCs in the forward region. The entire system is enclosed in a 0.5 T solenoid magnet. A progress report is given for the various components of the STAR detector system. The authors report on the recent developments in the detector proto-typing and construction, with an emphasis on the main TPC, recent TPC cosmic ray testing and shipping to Brookhaven National Laboratory.

  17. Overview of TPC Benchmark E: The Next Generation of OLTP Benchmarks

    NASA Astrophysics Data System (ADS)

    Hogan, Trish

    Set to replace the aging TPC-C, the TPC Benchmark E is the next generation OLTP benchmark, which more accurately models client database usage. TPC-E addresses the shortcomings of TPC-C. It has a much more complex workload, requires the use of RAID-protected storage, generates much less I/O, and is much cheaper and easier to set up, run, and audit. After a period of overlap, it is expected that TPC-E will become the de facto OLTP benchmark.

  18. A Monte Carlo analysis of the liquid xenon TPC as gamma ray telescope

    NASA Technical Reports Server (NTRS)

    Aprile, E.; Bolotnikov, A.; Chen, D.; Mukherjee, R.

    1992-01-01

    Extensive Monte Carlo modeling of a coded aperture x ray telescope based on a high resolution liquid xenon TPC has been performed. Results on efficiency, background reduction capability and source flux sensitivity are presented. We discuss in particular the development of a reconstruction algorithm for events with multiple interaction points. From the energy and spatial information, the kinematics of Compton scattering is used to identify and reduce background events, as well as to improve the detector response in the few MeV region. Assuming a spatial resolution of 1 mm RMS and an energy resolution of 4.5 percent FWHM at 1 MeV, the algorithm is capable of reducing by an order of magnitude the background rate expected at balloon altitude, thus significantly improving the telescope sensitivity.

  19. Meson and baryon correlation studies using the PEP-TPC/2. gamma. Facility

    SciTech Connect

    Ronan, M.T.

    1991-03-01

    Results on vector meson, and strange and charmed-baryon production are presented for data taken during the period 1982--1986 using the TPC/2{gamma} detector at PEP. Vector mesons ({rho}{sup 0}, K{sup *} and {phi}) with 0, 1 and 2 strange quarks are used to obtain redundant measures of strange-quark suppression and of the vector to pseudoscalar ratio in hadronization. Measurements of the production rates of {Lambda}, {Xi}{sup {minus}}, {Omega} and {Xi}{sup *0} hyperons and for the {Lambda}{sub c} and of rapidity correlations between {Lambda}{bar {Lambda}} pairs provide sensitive tests of baryon production in fragmentation models. In addition, two- and three-particle correlations between like sign pions provide further evidence for the Bose-Einstein effect in e{sup +}e{sup {minus}} interactions including the relativistic motion of particle sources. 9 refs., 7 figs.

  20. Thermophysical properties of argon

    SciTech Connect

    Jaques, A.

    1988-02-01

    The entire report consists of tables of thermodynamic properties (including sound velocity, thermal conductivity and diffusivity, Prandtl number, density) of argon at 86 to 400/degree/K, in the form of isobars over 0.9 to 100 bars. (DLC)

  1. Neutrino Detectors: Challenges and Opportunities

    SciTech Connect

    Soler, F. J. P.

    2011-10-06

    This paper covers possible detector options suitable at future neutrino facilities, such as Neutrino Factories, Super Beams and Beta Beams. The Magnetised Iron Neutrino Detector (MIND), which is the baseline detector at a Neutrino Factory, will be described and a new analysis which improves the efficiency of this detector at low energies will be shown. Other detectors covered include the Totally Active Scintillating Detectors (TASD), particularly relevant for a low energy Neutrino Factory, emulsion detectors for tau detection, liquid argon detectors and megaton scale water Cherenkov detectors. Finally the requirements of near detectors for long-baseline neutrino experiments will be demonstrated.

  2. Isentropic Compression of Argon

    SciTech Connect

    H. Oona; J.C. Solem; L.R. Veeser, C.A. Ekdahl; P.J. Rodriquez; S.M. Younger; W. Lewis; W.D. Turley

    1997-08-01

    We are studying the transition of argon from an insulator to a conductor by compressing the frozen gas isentropically to pressures at which neighboring atomic orbitals overlap sufficiently to allow some electron motion between atoms. Argon and the other rare gases have closed electron shells and therefore remain montomic, even when they solidify. Their simple structure makes it likely that any measured change in conductivity is due to changes in the atomic structure, not in molecular configuration. As the crystal is compressed the band gap closes, allowing increased conductivity. We have begun research to determine the conductivity at high pressures, and it is our intention to determine the compression at which the crystal becomes a metal.

  3. The commissioning of the O-TPC at TUNL

    NASA Astrophysics Data System (ADS)

    Seo, P.-N.; Ahmed, M. W.; Clinton, E. R.; Howell, C. R.; Stave, S. C.; Weller, H. R.; Young, A. H.; Gai, M.; Bromberger, B.; Dangendorf, V.; Tittelmeier, K.

    2008-04-01

    We are commissioning the Optical Readout Time Projection Chamber (O-TPC) that will be used in an experiment at the HIgS facility at TUNL for studying oxygen formation during stellar helium burning by studying the time reversed ^16O(,)^12C reaction. The initial calibration of the O-TPC was carried out at the LNS at Avery Point with a CMAC based data acquisition system. The tests at TUNL used a VME based data acquisition system that also controls a CCD camera. Under stable conditions an energy resolution as good as 2.6% was measured for the charge signal and single and double tracks of alpha particles from a ^148Gd source were recorded in the CCD camera. These tracks were analyzed using an automated pattern recognition algorithm that allows us to extract that track centroid (from which the scattering angle is deduced) as well as DE/DX along the track. The azimuthal angle of the track is deduced from the Time Projection. The O-TPC is found to be ready for accepting beams from the HIgS facility.

  4. Fission cross section uncertainties with the NIFFTE TPC

    NASA Astrophysics Data System (ADS)

    Sangiorgio, Samuele; Niffte Collaboration

    2014-09-01

    Nuclear data such as neutron-induced fission cross sections play a fundamental role in nuclear energy and defense applications. In recent years, understanding of these systems has become increasingly dependent upon advanced simulation and modeling, where uncertainties in nuclear data propagate in the expected performances of existing and future systems. It is important therefore that uncertainties in nuclear data are minimized and fully understood. For this reason, the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) uses a Time Projection Chamber (TPC) to measure energy-differential (n,f) cross sections with unprecedented precision. The presentation will discuss how the capabilities of the NIFFTE TPC allow to directly measures systematic uncertainties in fission cross sections, in particular for what concerns fission-fragment identification, and target and beam uniformity. Preliminary results from recent analysis of 238U/235U and 239Pu/235U data collected with the TPC will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Slow Control System for the NIFFTE Collaboration TPC

    NASA Astrophysics Data System (ADS)

    Ringle, Erik; Niffte Collaboration Collaboration

    2011-10-01

    As world energy concerns continue to dominate public policy in the 21st century, the need for cleaner and more efficient nuclear power is necessary. In order to effectively design and implement plans for generation IV nuclear reactors, more accurate fission cross-section measurements are necessary. The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration, in an effort to meet this need, has constructed a Time Projection Chamber (TPC) which aims to reduce the uncertainty of the fission cross-section to less than 1%. Using the Maximum Integration Data Acquisition System (MIDAS) framework, slow control measurements are integrated into a single interface to facilitate off-site monitoring. The Hart Scientific 1560 Black Stack will be used with two 2564 Thermistor Scanner Modules to monitor internal temperature of the TPC. A Prologix GPIB to Ethernet controller will be used to interface the hardware with MIDAS. This presentation will detail the design and implementation of the slow control system for the TPC. This work was supported by the U.S. Department of Energy Division of Energy Research.

  6. Argon Purification Reference and Recommendation

    SciTech Connect

    Wu, J.; /Fermilab

    1991-05-23

    This engineering note is a reference for future consideration on the purification of argon. The original concern was for the possibility of argon contamination from components in the cryostats over long-term storage. An argon purification system could also be useful for purifying the contents of the argon dewar. The general conclusion is that most of the systems researched are too expensive at this time, but the recommended choice would be Centorr Furnaces. There were three basic types of purification systems which were to be considered. The first was the molecular sieve. This method would have been the preferred one, because it was claimed that it could purify liquid argon, removing liquid oxygen from the argon. However, none of the commercial companies researched provided this type of purification for use with liquid argon. Most companies said that this type of purification was impossible, and tests at IB-4 confirmed this. The second system contained a copper oxide to remove gaseous oxygen from argon gas. The disadvantage of this system wass that the argon had to be heated to a gas, and then cooled back down to liquid. The third system was similar to the second, except that it used tungsten or another material like titanium. This system also needed to heat the argon to gas, however the advantage of this system was that it supposedly removed all contaminants, that is, everything except for inert gases. Of the three systems, the third is the type manufactured by Centorr Furnaces, which uses a titanium charge.

  7. The upgraded DØ detector

    NASA Astrophysics Data System (ADS)

    Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, D. L.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahmed, S. N.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Andeen, T.; Anderson, J. T.; Anderson, S.; Andrieu, B.; Angstadt, R.; Anosov, V.; Arnoud, Y.; Arov, M.; Askew, A.; Åsman, B.; Assis Jesus, A. C. S.; Atramentov, O.; Autermann, C.; Avila, C.; Babukhadia, L.; Bacon, T. C.; Badaud, F.; Baden, A.; Baffioni, S.; Bagby, L.; Baldin, B.; Balm, P. W.; Banerjee, P.; Banerjee, S.; Barberis, E.; Bardon, O.; Barg, W.; Bargassa, P.; Baringer, P.; Barnes, C.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bhattacharjee, M.; Baturitsky, M. A.; Bauer, D.; Bean, A.; Baumbaugh, B.; Beauceron, S.; Begalli, M.; Beaudette, F.; Begel, M.; Bellavance, A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Besson, A.; Beuselinck, R.; Beutel, D.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Binder, M.; Biscarat, C.; Bishoff, A.; Black, K. M.; Blackler, I.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Blumenschein, U.; Bockenthien, E.; Bodyagin, V.; Boehnlein, A.; Boeriu, O.; Bolton, T. A.; Bonamy, P.; Bonifas, D.; Borcherding, F.; Borissov, G.; Bos, K.; Bose, T.; Boswell, C.; Bowden, M.; Brandt, A.; Briskin, G.; Brock, R.; Brooijmans, G.; Bross, A.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Busato, E.; Buszello, C. P.; Butler, D.; Butler, J. M.; Cammin, J.; Caron, S.; Bystricky, J.; Canal, L.; Canelli, F.; Carvalho, W.; Casey, B. C. K.; Casey, D.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapin, D.; Charles, F.; Cheu, E.; Chevalier, L.; Chi, E.; Chiche, R.; Cho, D. K.; Choate, R.; Choi, S.; Choudhary, B.; Chopra, S.; Christenson, J. H.; Christiansen, T.; Christofek, L.; Churin, I.; Cisko, G.; Claes, D.; Clark, A. R.; Clément, B.; Clément, C.; Coadou, Y.; Colling, D. J.; Coney, L.; Connolly, B.; Cooke, M.; Cooper, W. E.; Coppage, D.; Corcoran, M.; Coss, J.; Cothenet, A.; Cousinou, M.-C.; Cox, B.; Crépé-Renaudin, S.; Cristetiu, M.; Cummings, M. A. C.; Cutts, D.; da Motta, H.; Das, M.; Davies, B.; Davies, G.; Davis, G. A.; Davis, W.; De, K.; de Jong, P.; de Jong, S. J.; De La Cruz-Burelo, E.; De La Taille, C.; De Oliveira Martins, C.; Dean, S.; Degenhardt, J. D.; Déliot, F.; Delsart, P. A.; Del Signore, K.; DeMaat, R.; Demarteau, M.; Demina, R.; Demine, P.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Doets, M.; Doidge, M.; Dong, H.; Doulas, S.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duperrin, A.; Dvornikov, O.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Edwards, T.; Ellison, J.; Elmsheuser, J.; Eltzroth, J. T.; Elvira, V. D.; Eno, S.; Ermolov, P.; Eroshin, O. V.; Estrada, J.; Evans, D.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Fagan, J.; Fast, J.; Fatakia, S. N.; Fein, D.; Feligioni, L.; Ferapontov, A. V.; Ferbel, T.; Ferreira, M. J.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fleck, I.; Fitzpatrick, T.; Flattum, E.; Fleuret, F.; Flores, R.; Foglesong, J.; Fortner, M.; Fox, H.; Franklin, C.; Freeman, W.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Gao, M.; Garcia, C.; Garcia-Bellido, A.; Gardner, J.; Gavrilov, V.; Gay, A.; Gay, P.; Gelé, D.; Gelhaus, R.; Genser, K.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Geurkov, G.; Ginther, G.; Gobbi, B.; Goldmann, K.; Golling, T.; Gollub, N.; Golovtsov, V.; Gómez, B.; Gomez, G.; Gomez, R.; Goodwin, R.; Gornushkin, Y.; Gounder, K.; Goussiou, A.; Graham, D.; Graham, G.; Grannis, P. D.; Gray, K.; Greder, S.; Green, D. R.; Green, J.; Green, J. A.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grinstein, S.; Gris, Ph.; Grivaz, J.-F.; Groer, L.; Grünendahl, S.; Grünewald, M. W.; Gu, W.; Guglielmo, J.; Gupta, A.; Gurzhiev, S. N.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hadley, N. J.; Haggard, E.; Haggerty, H.; Hagopian, S.; Hall, I.; Hall, R. E.; Han, C.; Han, L.; Hance, R.; Hanagaki, K.; Hanlet, P.; Hansen, S.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, C.; Hays, J.; Hazen, E.; Hebbeker, T.; Hebert, C.; Hedin, D.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Hou, S.; Houben, P.; Hu, Y.; Huang, J.; Huang, Y.; Hynek, V.; Huffman, D.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jacquier, Y.; Jaffré, M.; Jain, S.; Jain, V.; Jakobs, K.; Jayanti, R.; Jenkins, A.; Jesik, R.; Jiang, Y.; Johns, K.; Johnson, M.; Johnson, P.; Jonckheere, A.; Jonsson, P.; Jöstlein, H.; Jouravlev, N.; Juarez, M.; Juste, A.; Kaan, A. P.; Kado, M. M.; Käfer, D.; Kahl, W.; Kahn, S.; Kajfasz, E.

    2006-09-01

    The DØ experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DØ.

  8. First results of a large-area cryogenic gaseous photomultiplier coupled to a dual-phase liquid xenon TPC

    NASA Astrophysics Data System (ADS)

    Arazi, L.; Coimbra, A. E. C.; Erdal, E.; Israelashvili, I.; Rappaport, M. L.; Shchemelinin, S.; Vartsky, D.; dos Santos, J. M. F.; Breskin, A.

    2015-10-01

    We discuss recent advances in the development of cryogenic gaseous photomultipliers (GPM), for possible use in dark matter and other rare-event searches using noble-liquid targets. We present results from a 10 cm diameter GPM coupled to a dual-phase liquid xenon (LXe) TPC, demonstrating—for the first time—the feasibility of recording both primary (``S1'') and secondary (``S2'') scintillation signals. The detector comprised a triple Thick Gas Electron Multiplier (THGEM) structure with cesium iodide photocathode on the first element; it was shown to operate stably at 180 K with gains above 105, providing high single-photon detection efficiency even in the presence of large α particle-induced S2 signals comprising thousands of photoelectrons. S1 scintillation signals were recorded with a time resolution of 1.2 ns (RMS). The energy resolution (σ/E) for S2 electroluminescence of 5.5 MeV α particles was ~ 9%, which is comparable to that obtained in the XENON100 TPC with PMTs. The results are discussed within the context of potential GPM deployment in future multi-ton noble-liquid detectors.

  9. Development of a dedicated readout ASIC for TPC based X-ray polarimeter

    NASA Astrophysics Data System (ADS)

    Zhang, Hongyan; Deng, Zhi; Li, Hong; Liu, Yinong; Feng, Hua

    2016-07-01

    X-ray polarimetry with time projection chambers was firstly proposed by JK Black in 2007 and has been greatly developed since then. It measured two dimensional photoelectron tracks with one dimensional strip and the other dimension was estimated by the drift time from the signal waveforms. A readout ASIC, APV25, originally developed for CMS silicon trackers was used and has shown some limitations such as waveform sampling depth. A dedicated ASIC was developed for TPC based X-ray polarimeters in this paper. It integrated 32 channel circuits and each channel consisted of an analog front-end and a waveform sampler based on switched capacitor array. The analog front-end has a charge sensitive preamplifier with a gain of 25 mV/fC, a CR-RC shaper with a peaking time of 25 ns, a baseline holder and a discriminator for self-triggering. The SCA has a buffer latency of 3.2 μs with 64 cells operating at 20 MSPS. The ASIC was fabricated in a 0.18 μm CMOS process. The equivalent noise charge (ENC) of the analog front-end was measured to be 274.8 e+34.6 e/pF. The effective resolution of the SCA was 8.8 bits at sampling rate up to 50 MSPS. The total power consumption was 2.8 mW per channel. The ASIC was also tested with real TPC detectors and two dimensional photoelectron tracks have been successfully acquired. More tests and analysis on the sensitivity to the polarimetry are undergoing and will be presented in this paper.

  10. Operation of a liquid argon time projection chamber

    SciTech Connect

    Mahler, H.J.; Chen, H.H.; Doe, P.J.

    1983-02-01

    For the first time, the operation of a three-dimensional liquid argon time projection chamber has been demonstrated. This was accomplished in a 50 liter test detector using a readout plane with a woven structure etched on a PC-board.

  11. Near-infrared scintillation of liquid argon

    NASA Astrophysics Data System (ADS)

    Alexander, T.; Escobar, C. O.; Lippincott, W. H.; Rubinov, P.

    2016-03-01

    Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7 μm < λ < 1.5 μm). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab.

  12. TPC2 controls pigmentation by regulating melanosome pH and size.

    PubMed

    Ambrosio, Andrea L; Boyle, Judith A; Aradi, Al E; Christian, Keith A; Di Pietro, Santiago M

    2016-05-17

    Melanin is responsible for pigmentation of skin and hair and is synthesized in a specialized organelle, the melanosome, in melanocytes. A genome-wide association study revealed that the two pore segment channel 2 (TPCN2) gene is strongly linked to pigmentation variations. TPCN2 encodes the two-pore channel 2 (TPC2) protein, a cation channel. Nevertheless, how TPC2 regulates pigmentation remains unknown. Here, we show that TPC2 is expressed in melanocytes and localizes to the melanosome-limiting membrane and, to a lesser extent, to endolysosomal compartments by confocal fluorescence and immunogold electron microscopy. Immunomagnetic isolation of TPC2-containing organelles confirmed its coresidence with melanosomal markers. TPCN2 knockout by means of clustered regularly interspaced short palindromic repeat/CRISPR-associated 9 gene editing elicited a dramatic increase in pigment content in MNT-1 melanocytic cells. This effect was rescued by transient expression of TPC2-GFP. Consistently, siRNA-mediated knockdown of TPC2 also caused a substantial increase in melanin content in both MNT-1 cells and primary human melanocytes. Using a newly developed genetically encoded pH sensor targeted to melanosomes, we determined that the melanosome lumen in TPC2-KO MNT-1 cells and primary melanocytes subjected to TPC2 knockdown is less acidic than in control cells. Fluorescence and electron microscopy analysis revealed that TPC2-KO MNT-1 cells have significantly larger melanosomes than control cells, but the number of organelles is unchanged. TPC2 likely regulates melanosomes pH and size by mediating Ca(2+) release from the organelle, which is decreased in TPC2-KO MNT-1 cells, as determined with the Ca(2+) sensor tyrosinase-GCaMP6. Thus, our data show that TPC2 regulates pigmentation through two fundamental determinants of melanosome function: pH and size. PMID:27140606

  13. The Argon Geochronology Experiment (AGE)

    NASA Technical Reports Server (NTRS)

    Swindle, T. D.; Bode, R.; Fennema, A.; Chutjian, A.; MacAskill, J. A.; Darrach, M. R.; Clegg, S. M.; Wiens, R. C.; Cremers, D.

    2006-01-01

    This viewgraph presentation reviews the Argon Geochronology Experiment (AGE). Potassium-Argon dating is shown along with cosmic ray dating exposure. The contents include a flow diagram of the Argon Geochronology Experiment, and schematic diagrams of the mass spectrometer vacuum system, sample manipulation mechanism, mineral heater oven, and the quadrupole ion trap mass spectrometer. The Laser-Induced Breakdown Spectroscopy (LIBS) Operation with elemental abundances is also described.

  14. Isentropic compression of argon

    SciTech Connect

    Veeser, L.R.; Ekdahl, C.A.; Oona, H.

    1997-06-01

    The compression was done in an MC-1 flux compression (explosive) generator, in order to study the transition from an insulator to a conductor. Since conductivity signals were observed in all the experiments (except when the probe is removed), both the Teflon and the argon are becoming conductive. The conductivity could not be determined (Teflon insulation properties unknown), but it could be bounded as being {sigma}=1/{rho}{le}8({Omega}cm){sub -1}, because when the Teflon breaks down, the dielectric constant is reduced. The Teflon insulator problem remains, and other ways to better insulate the probe or to measure the conductivity without a probe is being sought.

  15. Transaction Processing Performance Council (TPC): Twenty Years Later - A Look Back, a Look Ahead

    NASA Astrophysics Data System (ADS)

    Nambiar, Raghunath Othayoth; Lanken, Matthew; Wakou, Nicholas; Carman, Forrest; Majdalany, Michael

    The Transaction Processing Performance Council (TPC) [1] is a non-profit corporation founded to define transaction processing and database benchmarks and to disseminate objective, verifiable TPC performance data to the industry. Established in August 1988, the TPC has been integral in shaping the landscape of modern transaction processing and database benchmarks over the past twenty years. Today the TPC is developing an energy efficiency metric and a new ETL benchmark, as well as investigating new areas for benchmark development in 2010 and beyond.

  16. Exploration of Argon PSD with the MiniCLEAN 39Ar Spike

    NASA Astrophysics Data System (ADS)

    Ronquest, Michael

    2013-04-01

    MiniCLEAN is a single-phase WIMP dark matter experiment which observes scintillation light from a 150kg fiducial mass liquid argon target. This design utilizes argon's powerful pulse shape discrimination (PSD) capability in order to identify and separate electron recoil backgrounds from WIMP-induced nuclear recoil signals. Experimental knowledge of the efficacy of argon PSD, as a function of photoelectron statistics and electron recoil energy, would inform the design and physics reach of the next generation of detectors. MiniCLEAN will perform the best measurement to date of argon PSD by utilizing a novel technique of ``spiking'' the detector with additional amounts of 39Ar. This unstable isotope produces beta decays at a level of 1Bq/kg in natural argon, and thus presents a major background for argon based experiments. Produced using the irradiation of potassium salts, the 39Ar spike will be injected into MiniCLEAN to produce ``enriched argon'' with the data compared to a prior run using natural argon. The difference in the number and distribution of candidate events between the two runs will yield the magnitude and shape of the argon PSD leakage background PDF. This talk will review the motivation, production and use of the 39Ar spike in MiniCLEAN.

  17. Measuring Muon-Neutrino Charged-Current Differential Cross Sections with a Liquid Argon Time Projection Chamber

    SciTech Connect

    Spitz, Joshua B.

    2011-01-01

    More than 80 years after its proposed existence, the neutrino remains largely mysterious and elusive. Precision measurements of the neutrino's properties are just now beginning to take place. Such measurements are required in order to determine the mass of the neutrino, how many neutrinos there are, if neutrinos are different than anti-neutrinos, and more. Muon-neutrino charged-current differential cross sections on an argon target in terms of the outgoing muon momentum and angle are presented. The measurements have been taken with the ArgoNeuT Liquid Argon Time Projection Chamber (LArTPC) experiment. ArgoNeuT is the first LArTPC to ever take data in a low energy neutrino beam, having collected thousands of neutrino and anti-neutrino events in the NuMI beamline at Fermilab. The results are relevant for long baseline neutrino oscillation experiments searching for non-zero $\\theta_{13}$, CP-violation in the lepton sector, and the sign of the neutrino mass hierarchy, among other things. Furthermore, the differential cross sections are important for understanding the nature of the neutrino-nucleus interaction in general. These measurements represent a significant step forward for LArTPC technology as they are among the first neutrino physics results with such a device.

  18. A 4. pi. tracking TPC magnetic spectrometer for RHIC

    SciTech Connect

    Danby, G.; Eiseman, S.E.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C.; Van Dijk, J.H. ); Lindenbaum, S.J. City Coll., New York, NY ); Chan, C.S.; Kramer, M.A.; Zhao, K. ); Biswas, N.; Kenney, P.; Piekarz, J. (Notre Dame Univ

    1990-01-01

    The primary physics objective of the 4{pi} TPC magnetic spectrometer proposal is to search for the Quark-Gluon Plasma. In previous workshops we have discussed what the possible hadronic signatures of such a state of matter would be. Succinctly, the QGP is a direct prediction of non-perturbative QCD. Therefore the question of the existence of this new state of matter bears directly on the validity of non-perturbative QCD. However, since non-perturbative QCD has never been established, it is apparent that what may await us is a host of new phenomena that will go beyond the standard model.

  19. Argon Welding Inside A Workpiece

    NASA Technical Reports Server (NTRS)

    Morgan, Gene E.

    1988-01-01

    Canopies convert large hollow workpiece into inert-gas welding chamber. Large manifold serves welding chamber for attachment of liner parts in argon atmosphere. Every crevice, opening and passageway provided with argon-rich environment. Weld defects and oxidation dramatically reduced; also welding time reduced.

  20. Photoionization of argon clusters

    SciTech Connect

    Dehmer, Patricia M.; Pratt, Stephen T.

    1982-01-01

    Argon clusters were produced in a free supersonic molecular beam expansion of pure argon at room temperature and the photoionization efficiency curves of the trimer through hexamer were measured in the wavelength regions from threshold to 700 Â. A study of the Ar⁺3 photoionization efficiency curve as a function of nozzle stagnation pressure shows that fragmentation of heavier clusters can dominate the spectrum, even near threshold, and even when the nozzle conditions are such that the Ar⁺4 intensity is only a small fraction of the Ar⁺3 intensity. The Ar⁺3 photoionization efficiency curve, obtained using nozzle stagnation conditions such that no heavier ions were detected, exhibits several broad peaks near threshold which show similarities to bands of the dimer. At high nozzle stagnation pressures, the photoionization efficiency curves for Ar⁺3 to Ar⁺6 are nearly identical due to the effects of fragmentation. These spectra exhibit two very broad features which are similar to features observed in the solid. The threshold regions for all the positive ions show extremely gradual onsets, making it difficult to determine the appearance potentials accurately. The appearance potentials for Ar⁺2 and Ar⁺3 are 855.0±1.5 and 865.0±1.5 Â, respectively, yielding a value of 0.18±0.05 eV for the dissociation energy of Ar⁺3. The appearance potentials for the heavier clusters Ar⁺4 through Ar⁺6 are all approximately 870±2 Â.

  1. Heavy ion reaction measurements with the EOS TPC (looking for central collisions with missing energy)

    SciTech Connect

    Wieman, H.H.; EOS Collaboration

    1994-05-01

    The EOS TPC was constructed for complete event measurement of heavy ion collisions at the Bevalac. We report here on the TPC design and some preliminary measurements of conserved event quantities such as total invariant mass, total momentum, total A and Z.

  2. The LUX-Zeplin Dark Matter Detector

    NASA Astrophysics Data System (ADS)

    Mock, Jeremy; Lux-Zeplin (Lz) Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) detector is a second generation dark matter experiment that will operate at the 4850 foot level of the Sanford Underground Research Experiment as a follow-up to the LUX detector, currently the world's most sensitive WIMP direct detection experiment. The LZ detector will contain 7 tonnes of active liquid xenon with a 5.6 tonne fiducial mass in the TPC. The TPC is surrounded by an active, instrumented, liquid-xenon ``skin'' region to veto gammas, then a layer of liquid scintillator to veto neutrons, all contained within a water shield. Modeling the detector is key to understanding the expected background, which in turn leads to a better understanding of the projected sensitivity, currently expected to be 2e-48 cm2 for a 50 GeV WIMP. I will discuss the current status of the LZ experiment as well as its projected sensitivity.

  3. Large solid angle tracking of Monte Carlo events of heavy ion collisions in TPC magnetic spectrometers

    SciTech Connect

    Lindenbaum, S.J.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C.; Asoka-Kumar, P.P.V.

    1986-01-01

    The collision of 15 GeV/nucleon sulfur and carbon or oxygen ions with various fixed targets such as carbon, sulfur, and gold is to be observed in the MPS magnetic spectrometer with a time projection chamber (TPC) module. This TPC will be placed just downstream of the target and be able to track approximately 50% of all charged particles. The design and construction of the TPC is proceeding, and prototypes of the TPC readout system have been tested and production devices are to be delivered. A TPC track reconstruction program has been developed. Monte Carlo events have been generated and tracked. The track reconstruction program consists of three parts: a local pattern recognition which associates contiguous readouts on adjacent readout wires to form a single hit; a subroutine which positions the hits into slices in the vertical plane; and the track reconstruction section. (LEW)

  4. Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

    SciTech Connect

    Cao, H.

    2015-05-26

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We also report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0 to 970 V/cm. For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V/cm. Furthermore, we report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83mKr internal conversion electrons is comparable to that from 207Bi conversion electrons, we obtained the numbers of excitons (Nex) and ion pairs (Ni) and their ratio (Nex/Ni) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.

  5. Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

    DOE PAGESBeta

    Cao, H.

    2015-05-26

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We also report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0more » to 970 V/cm. For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V/cm. Furthermore, we report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83mKr internal conversion electrons is comparable to that from 207Bi conversion electrons, we obtained the numbers of excitons (Nex) and ion pairs (Ni) and their ratio (Nex/Ni) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.« less

  6. Microwave Argon Plasma Torch

    NASA Astrophysics Data System (ADS)

    Felizardo, Edgar; Pencheva, Mariana; Benova, Evgenia; Dias, Fransisco; Tatarova, Elena

    2009-10-01

    A theoretical and experimental investigation of a microwave (2.45 GHz) Argon plasma torch driven by a surface wave is presented. The theoretical model couples in a self-consistent way the wave electrodynamics and the electron and heavy particle kinetics. The set of coupled equations includes: Maxwell's equations, the electron Boltzmann equation, including electron-electron collisions, and the particle balance equations for electrons, excited atoms (4s, 4p, 3d, 5s, 5p, 4d, 6s), and atomic (Ar^+) and molecular ions (Ar2^+). The input parameters of the model are: gas pressure (760 Torr), plasma radius (R = 0.75 cm), dielectric permittivity (ɛd = 4.0) and tube thickness (d = 0.15 cm) as well as the measured axial profile of the gas temperature (3500 K - 1500 K). The latter was determined from measurements of the rotational temperature of the OH molecular band in the range 306 - 315 nm. Phase and amplitude sensitive recording provides the data for the axial wavenumber and wave attenuation coefficient. The wavenumber decreases along the generated plasma torch. The electron density (Ne) axial profile as determined from measurements of Hβ Stark broadening is in agreement with the theoretical one.

  7. Upgrade of the ALICE TPC FEE online radiation monitoring system

    NASA Astrophysics Data System (ADS)

    RØed, K.; Alme, J.; Askeland, E.; David, E.; Gunji, T.; Helstrup, H.; Kiss, T.; Lippmann, C.; Rehman, A.; Röhrich, D.; Ullaland, K.; Velure, A.; Zhao, C.

    2015-12-01

    This paper presents the radiation monitoring system on the Readout Control Unit (RCU) of the the ALICE TPC Front End Electronics. In Run 1, Single Event Upsets (SEUs) in the configuration memory of an SRAM based FPGA were counted, and the results from different run periods with stable beam conditions are presented. For Run 2, a new RCU, the RCU2, has been designed in order to achieve higher data readout rates and increase radiation tolerance. The RCU2 also includes a new radiation monitor solution with increased sensitivity, which is based on counting the number of SEUs in dedicated SRAM memories. The paper presents this new solution together with the results from the targeted irradiation campaigns.

  8. Performance simulation studies for the ALICE TPC GEM upgrade

    NASA Astrophysics Data System (ADS)

    Ljunggren, M.

    2016-07-01

    To be able to exploit the anticipated interaction rate of 50 kHz in Pb-Pb collisions during run 3 of the LHC (beyond 2019), the ALICE TPC will be upgraded to allow continuous readout. As this is not possible with the current Multi Wire Proportional Chamber (MWPC) based amplification, the readout will be replaced with Gas Electron Multiplier (GEM) readout chambers that can suppress ~ 99% of the ion back flow. The space charge of the remaining 1% ion back flow, however, will cause significant distortions to the measured tracks of order cm. Simulation studies to characterize the distortions and test correction strategies have been performed, which show that the intrinsic momentum resolution, without these distortions, can be recovered.

  9. Readout of TPC Tracking Chambers with GEMs and Pixel Chip

    SciTech Connect

    Kadyk, John; Kim, T.; Freytsis, M.; Button-Shafer, J.; Kadyk, J.; Vahsen, S.E.; Wenzel, W.A.

    2007-12-21

    Two layers of GEMs and the ATLAS Pixel Chip, FEI3, have been combined and tested as a prototype for Time Projection Chamber (TPC) readout at the International Linear Collider (ILC). The double-layer GEM system amplifies charge with gain sufficient to detect all track ionization. The suitability of three gas mixtures for this application was investigated, and gain measurements are presented. A large sample of cosmic ray tracks was reconstructed in 3D by using the simultaneous timing and 2D spatial information from the pixel chip. The chip provides pixel charge measurement as well as timing. These results demonstrate that a double GEM and pixel combination, with a suitably modified pixel ASIC, could meet the stringent readout requirements of the ILC.

  10. Effects of Nitrogen contamination in liquid Argon

    NASA Astrophysics Data System (ADS)

    Acciarri, R.; Antonello, M.; Baibussinov, B.; Baldo-Ceolin, M.; Benetti, P.; Calaprice, F.; Calligarich, E.; Cambiaghi, M.; Canci, N.; Carbonara, F.; Cavanna, F.; Centro, S.; Cocco, A. G.; Di Pompeo, F.; Fiorillo, G.; Galbiati, C.; Gallo, V.; Grandi, L.; Meng, G.; Modena, I.; Montanari, C.; Palamara, O.; Pandola, L.; Piano Mortari, G. B.; Pietropaolo, F.; Raselli, G. L.; Roncadelli, M.; Rossella, M.; Rubbia, C.; Segreto, E.; Szelc, A. M.; Ventura, S.; Vignoli, C.

    2010-06-01

    A dedicated test of the effects of Nitrogen contamination in liquid Argon has been performed at the INFN-Gran Sasso Laboratory (LNGS, Italy) within the WArP R&D program. A detector has been designed and assembled for this specific task and connected to a system for the injection of controlled amounts of gaseous Nitrogen into the liquid Argon. The purpose of the test is to detect the reduction of the Ar scintillation light emission as a function of the amount of the Nitrogen contaminant injected in the Argon volume. A wide concentration range, spanning from ~ 10-1 ppm up to ~ 103 ppm, has been explored. Measurements have been done with electrons in the energy range of minimum ionizing particles (γ-conversion from radioactive sources). Source spectra at different Nitrogen contaminations are analyzed, showing sensitive reduction of the scintillation yield at increasing concentrations. Direct PMT signal acquisition exploiting high time resolution by fast waveform recording allowed high precision extraction of the main characteristics of the scintillation light emission in contaminated LAr. In particular, the decreasing behavior in lifetime and relative amplitude of the slow component is found to be appreciable starting from Script O(1 ppm) of Nitrogen concentrations. The rate constant of the quenching process induced by Nitrogen in liquid Ar has been found to be kQ(N2) = 0.11 ± 0.01 μs-1ppm-1, consistent with a previous measurement of this quantity but with significant improvement in precision. On the other hand, no evidence for absorption by N2 impurities has been found up to the higher concentrations here explored.

  11. First measurement of the ionization yield of nuclear recoils in liquid argon

    SciTech Connect

    Joshi, T.; Sangiorgio, Samuele; Bernstein, A.; Foxe, Michael P.; Hagmann, Chris; Jovanovic, Igor; Kazkaz, K.; Mozin, Vladimir V.; Norman, E. B.; Pereverzev, S. V.; Rebassoo, Finn O.; Sorensen, Peter F.

    2014-05-01

    Liquid phase argon has long been used as a target medium for particle detection via scintillation light. Recently there has been considerable interest in direct detection of both hypothetical darkmatter particles and coherent elastic neutrino nucleus scattering. These as-yet unobserved neutral particle interactions are expected to result in a recoiling argon atom O(keV), generally referred to in the literature as a nuclear recoil. This prompts the question of the available electromagnetic signal in a liquid argon detector. In this Letter we report the first measurement of the ionization yield (Qy), detected electrons per unit energy, resulting from nuclear recoils in liquid argon, measured at 6.7 keV. This is also the lowest energy measurement of nuclear recoils in liquid argon.

  12. TPC-V: A Benchmark for Evaluating the Performance of Database Applications in Virtual Environments

    NASA Astrophysics Data System (ADS)

    Sethuraman, Priya; Reza Taheri, H.

    For two decades, TPC benchmarks have been the gold standards for evaluating the performance of database servers. An area that TPC benchmarks had not addressed until now was virtualization. Virtualization is now a major technology in use in data centers, and is the number one technology on Gartner Group's Top Technologies List. In 2009, the TPC formed a Working Group to develop a benchmark specifically intended for virtual environments that run database applications. We will describe the characteristics of this benchmark, and provide a status update on its development.

  13. The Upgraded D0 detector

    SciTech Connect

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, D.L.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahmed, S.N.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G.A.; Anastasoaie, M.; Andeen, T.; Anderson, J.T.; Anderson, S.; /Buenos Aires U. /Rio de Janeiro, CBPF /Sao Paulo, IFT /Alberta U. /Simon Fraser U. /York U., Canada /McGill U. /Beijing, Inst. High Energy Phys. /Hefei, CUST /Andes U., Bogota /Charles U. /Prague, Tech. U. /Prague, Inst. Phys. /San Francisco de Quito U. /Clermont-Ferrand U. /LPSC, Grenoble /Marseille, CPPM /Orsay, LAL /Paris U., VI-VII /DAPNIA, Saclay /Strasbourg, IReS

    2005-07-01

    The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.

  14. Quenching gas for detectors of charged particles

    DOEpatents

    Atac, M.

    1974-01-22

    Operation of detectors of charged particles such as wire counters and Geiger-Muller tubes is improved by filling the counters with a quenching-gas mixture of argon, isobutane and methylchloroform. (Official Gazette)

  15. Behavior of TPC`s in a high particle flux environment

    SciTech Connect

    Etkin, A.; Eisemann, S.E.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C.; Lindenbaum, S.J. |; Chan, C.S.; Kramer, M.A.; Zhao, K.H.; Zhu, Y.; Hallman, T.J.; Madansky, L.; Ahmad, S.; Bonner, B.E.; Buchanan, J.A.; Chiou, C.N.; Clement, J.M.; Mutchler, G.S.; Roberts, J.B.

    1991-12-13

    TPC`s (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchrotron) were exposed to fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to find if such high fluxes cause gain changes or distortions of the electric field. Initial results of these and other tests are presented and the consequences for the RHIC (Relativistic Heavy Ion Collider) TPC-based experiments are discussed.

  16. Behavior of TPC`s in a high particle flux environment

    SciTech Connect

    Etkin, A.; Eiseman, S.E.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C.; Lindenbaum, S.J.; Chan, C.S.; Kramer, M.A.; Zhao, K.H.; Zhu, Y.; Hallman, T.J.; Madansky, L.; Ahmad, S.; Bonner, B.E.; Buchanan, J.A.; Chiou, C.N.; Clement, J.M.; Mutchler, G.S.; Roberts, J.B.

    1991-12-31

    TPC`s (Time Projection Chamber) used in E-810 at the TAGS (Alternating Gradient Synchrotron) were exposed to fluxes equivalent to more than 10 minimum ionizing particles per second to find if such high fluxes cause gain changes or distortions of the electric field. Initial results of these and other tests are presented and the consequences for the RHIC (Relativistic Heavy Ion Collider) TPC-based experiments are discussed.

  17. Radiative Properties of Argon Gas-Puff Implosions on COBRA

    NASA Astrophysics Data System (ADS)

    Ouart, Nicholas; Qi, Niansheng; de Grouchy, Phil; Shelkovenko, Tatiana; Pikuz, Sergei; Giuliani, John; Dasgupta, Arati; Apruzese, John; Clark, Robert; Hammer, David; Kusse, Bruce

    2015-11-01

    Gas-puff Z-pinch experiments were performed on the 1 MA COBRA pulsed power generator at Cornell University. The gas puffs were injected into the load region from a triple nozzle. The load region had an anode-cathode gap of 2.5 cm. The standard diagnostics on COBRA include time-integrated pinhole cameras, a time-integrated axially resolved x-ray spectrometer, filtered photo-conducting detectors, and time-gated XUV cameras. We will focus mainly on results from pinhole images and x-ray spectra from argon gas puffs including some with a SO2 dopant. The x-ray time-integrated pinhole images feature a tight axially uniform plasma column with a diameter of approximately 1 mm for argon gas implosion. The x-ray spectrometer used mica crystals (2d =19.84 Å) and captured the argon K-shell radiation from different crystal reflections. A 1-D multi-zone argon and sulfur non-LTE kinetics code with radiation transport is used to model the K-shell emission for the purpose of inferring the plasma conditions and the interaction of gas from the inner annulus with the central jet. This work is supported by DOE/NNSA.

  18. The ATLAS Liquid Argon Calorimeter: Construction, Integration, Commissioning

    SciTech Connect

    Aleksa, Martin

    2006-10-27

    The ATLAS liquid argon (LAr) calorimeter system consists of an electromagnetic barrel calorimeter and two end caps with electromagnetic, hadronic and forward calorimeters. The liquid argon sampling technique, with an accordion geometry was chosen for the barrel electromagnetic calorimeter (EMB) and adapted to the end cap (EMEC). The hadronic end cap calorimeter (HEC) uses a copper-liquid argon sampling technique with flat plate geometry and is subdivided in depth in two wheels per end-cap. Finally, the forward calorimeter (FCAL) is composed of three modules employing cylindrical electrodes with thin liquid argon gaps.The construction of the full calorimeter system is complete since mid-2004. Production modules constructed in the home institutes were integrated into wheels at CERN in 2003-2004, and inserted into the three cryostats. They passed their first complete cold test before the lowering into the ATLAS cavern. Results of quality checks (e.g. electrical, mechanical, ...) performed on all the 190304 read-out channels after cool down will be reported. End 2004 the ATLAS barrel electromagnetic (EM) calorimeter was installed in the ATLAS cavern and since summer 2005 the front-end electronics are being connected and tested. Results of this first commissioning phase will be shown to demonstrate the high standards of quality control for our detectors.

  19. Demonstration and comparison of photomultiplier tubes at liquid Argon temperature

    NASA Astrophysics Data System (ADS)

    Acciarri, R.; Antonello, M.; Boffelli, F.; Cambiaghi, M.; Canci, N.; Cavanna, F.; Cocco, A. G.; Deniskina, N.; Di Pompeo, F.; Fiorillo, G.; Galbiati, C.; Grandi, L.; Kryczynski, P.; Meng, G.; Montanari, C.; Palamara, O.; Pandola, L.; Perfetto, F.; Piano Mortari, G. B.; Pietropaolo, F.; Raselli, G. L.; Rubbia, C.; Segreto, E.; Szelc, A. M.; Triossi, A.; Ventura, S.; Vignoli, C.; Zani, A.

    2012-01-01

    Liquified noble gases are widely used as a target in direct Dark Matter searches. Signals from scintillation in the liquid, following energy deposition from the recoil nuclei scattered by Dark Matter particles (e.g. WIMPs), should be recorded down to very low energies by photosensors suitably designed to operate at cryogenic temperatures. Liquid Argon based detectors for Dark Matter searches currently implement photomultiplier tubes for signal read-out. In the last few years PMTs with photocathodes operating down to liquid Argon temperatures (87 K) have been specially developed with increasing Quantum Efficiency characteristics. The most recent of these, Hamamatsu Photonics K.K. Mod. R11065 with peak QE up to about 35%, has been extensively tested within the R&D program of the WArP Collaboration. During these tests the Hamamatsu PMTs showed excellent performance and allowed obtaining a light yield around 7 phel/keVee in a Liquid Argon detector with a photocathodic coverage in the 12% range, sufficient for detection of events down to few keVee of energy deposition. This shows that this new type of PMT is suited for experimental applications, in particular for new direct Dark Matter searches with LAr-based experiments.

  20. Searching for dark matter with single phase liquid argon

    NASA Astrophysics Data System (ADS)

    Caldwell, Thomas S., Jr.

    The first hint that we fail to understand the nature of a large fraction of the gravitating matter in the universe came from Fritz Zwicky's measurements of the velocity distribution of the Coma cluster in 1933. Using the Virial theorem, Zwicky found that galaxies in the cluster were orbiting far too fast to remain gravitationally bound when their mass was estimated by the brightness of the visible matter. This led to the postulation that some form of non-luminous dark matter is present in galaxies comprising a large fraction of the galactic mass. The nature of this dark matter remains yet unknown over 80 years after Zwicky's measurements despite the efforts of many experiments. Dark matter is widely believed to be a beyond the Standard Model particle which brings the dark matter problem into the realm of particle physics. Supersymmetry is one widely explored extension of the Standard model, from which particles meeting the constraints on dark matter properties can naturally arise. These particles are generically termed weakly interacting massive particles (WIMPs), and are a currently favored dark matter candidate. A variety of experimental efforts are underway aimed towards direct detection of dark matter through observation of rare scattering of WIMPs in terrestrial detectors. Single phase liquid argon detectors are an appealing WIMP detection technique due to the scintillation properties of liquid argon and the scalability of the single phase approach. The MiniCLEAN dark matter detector is a single phase liquid argon scintillation scintillation detector with a 500 kg active mass. The modular design offers 4pi coverage with 92 optical cassettes, each containing TPB coated acrylic and a cryogenic photomultiplier tube. The MiniCLEAN detector has recently completed construction at SNOLAB. The detector is currently being commissioned, and will soon begin operation with the liquid argon target. Utilizing advanced pulse-shape discrimination techniques, MiniCLEAN will

  1. Attainable superheat of argon-helium, argon-neon solutions.

    PubMed

    Baidakov, Vladimir G; Kaverin, Aleksey M; Andbaeva, Valentina N

    2008-10-16

    The method of lifetime measurement has been used to investigate the kinetics of spontaneous boiling-up of superheated argon-helium and argon-neon solutions. Experiments were made at a pressure of p = 1.5 MPa and concentrations up to 0.33 mol% in the range of nucleation rates from 10 (4) to 10 (8) s (-1) m (-3). The homogeneous nucleation regime has been distinguished. With good agreement between experimental data and homogeneous nucleation theory in temperature and concentration dependences of the nucleation rate, a systematic underestimation by 0.25-0.34 K has been revealed in superheat temperatures over the saturated line attained by experiment as compared with theoretical values calculated in a macroscopic approximation. The revealed disagreement between theory and experiment is connected with the dependence of the properties of new-phase nuclei on their size. PMID:18798666

  2. The Gridpix Detector: History and Perspective

    NASA Astrophysics Data System (ADS)

    van der Graaf, Harry; Aarnink, Tom; Aarts, Arno; van Bakel, Niels; Berbee, Edward; Berkien, Ad; van Beuzekom, Martin; Bosma, Marten; Campbell, Michael; Chefdeville, Max; Colas, Paul; Colijn, Auke-Pieter; Fornaini, Alessandro; Fransen, Martin; Giganon, Arnaud; Giomataris, Ioannis; Gotink, Wim; de Groot, Nicolo; Hartjes, Fred; van der Heijden, Bas; Hessey, Nigel; Jansweijer, Peter; Konig, Adriaan; Koppert, Wilco; Llopart, Xavi; de Nooij, Lucie; van der Putten, Sipho; Rövekamp, Joop; Salm, Cora; Bello, D. San Segundo; Schmitz, Jurriaan; Smits, Sander; Timmermans, Jan; Verkooijen, Hans; Visschers, Jan; Visser, Jan; Wijnen, Thei; Wyrsch, Nicolas

    2013-04-01

    In 2000, the requirements for a large TPC for experiments at a new linear collider were formulated. Both the GEM and Micromegas gas amplification systems had matured, such that they could be practically applied. With the Medipix chip, a pixel-segmented anode readout became possible, offering an unprecedented level of granularity and sensitivity. The single electron sensitive device is a digital detector capable to record and transfer all information of the primary ionization, provided that it can be made discharge proof.

  3. Lysosomal two-pore channel subtype 2 (TPC2) regulates skeletal muscle autophagic signaling.

    PubMed

    Lin, Pei-Hui; Duann, Pu; Komazaki, Shinji; Park, Ki Ho; Li, Haichang; Sun, Mingzhai; Sermersheim, Mathew; Gumpper, Kristyn; Parrington, John; Galione, Antony; Evans, A Mark; Zhu, Michael X; Ma, Jianjie

    2015-02-01

    Postnatal skeletal muscle mass is regulated by the balance between anabolic protein synthesis and catabolic protein degradation, and muscle atrophy occurs when protein homeostasis is disrupted. Autophagy has emerged as critical in clearing dysfunctional organelles and thus in regulating protein turnover. Here we show that endolysosomal two-pore channel subtype 2 (TPC2) contributes to autophagy signaling and protein homeostasis in skeletal muscle. Muscles derived from Tpcn2(-/-) mice exhibit an atrophic phenotype with exacerbated autophagy under starvation. Compared with wild types, animals lacking TPC2 demonstrated an enhanced autophagy flux characterized by increased accumulation of autophagosomes upon combined stress induction by starvation and colchicine treatment. In addition, deletion of TPC2 in muscle caused aberrant lysosomal pH homeostasis and reduced lysosomal protease activity. Association between mammalian target of rapamycin and TPC2 was detected in skeletal muscle, allowing for appropriate adjustments to cellular metabolic states and subsequent execution of autophagy. TPC2 therefore impacts mammalian target of rapamycin reactivation during the process of autophagy and contributes to maintenance of muscle homeostasis. PMID:25480788

  4. Thermal information regarding the cooldown and operation of liquid argon calorimeters

    SciTech Connect

    Rucinski, R.A.; Cooper, W.E.; Dixon, K.D.; Krempetz, K.J.; Mulholland, G.T.; Primdahl, K.; Urbin, J.B.

    1994-12-31

    Three liquid argon calorimeters were cooled down and operated as part of the D-Zero detector at Fermi National Accelerator laboratory. The largest vessel contains 248 metric tons of uranium and copper plates and 19 kL (5000 gal.) of liquid argon. The other two vessels are mirror images, each containing 185 metric tons of uranium and stainless steel plates and 12.1 kL (3200 gal.) of liquid argon. The cooldown was accomplished by convection heat transfer between boiling, liquid nitrogen filled finned heat exchangers and argon gas inside the vessels. Information regarding the general internal geometry of the calorimeters, cooldown, operation, and steady state heat loads will be presented.

  5. Thermal information regarding the cooldown and operation of liquid argon calorimeters

    SciTech Connect

    Rucinski, R.A.; Cooper, W.E.; Dixon, K.D.; Krempetz, K.J.; Mulholland, G.T.; Primdahl, K.; Urbin, J.B.

    1993-07-01

    Three liquid argon calorimeters were cooled down and operated as part of the D-Zero detector at Fermi National Accelerator laboratory. The largest vessel contains 248 metric tons of uranium and copper plates and 19 kL (5000 gal.) of liquid argon. The other two vessels are mirror images, each containing 185 metric tons of uranium and stainless steel plates and 12.1 kL (3200 gal.) of liquid argon. The cool down was accomplished by convection heat transfer between boiling liquid nitrogen filled finned heat exchangers and argon gas inside the vessels. Information regarding the general internal geometry of the calorimeters, cool down, operation, and steady state heat loads will be presented.

  6. Tetrapac (tpc), a novel genotype of Neisseria gonorrhoeae affecting epithelial cell invasion, natural transformation competence and cell separation.

    PubMed

    Fussenegger, M; Kahrs, A F; Facius, D; Meyer, T F

    1996-03-01

    We characterized a novel mutant phenotype (tetrapac, tpc) of Neisseria gonorrhoeae (Ngo) associated with a distinctive rough-colony morphology and bacterial growth in clusters of four. This phenotype, suggesting a defect in cell division, was isolated from a mutant library of Ngo MS11 generated with the phoA minitransposon TnMax4. The tpc mutant shows a 30% reduction in the overall murein hydrolase activity using Escherichia coli murein as substrate. Tetrapacs can be resolved by co-cultivation with wild-type Ngo, indicating that Tpc is a diffusible protein. Interestingly, Tpc is absolutely required for the natural transformation competence of piliated Ngo. Mutants in tpc grow normally, but show a approximately 10-fold reduction in their ability to invade human epithelial cells. The tpc sequence reveals an open reading frame of approximately 1 kb encoding a protein (Tpc) of 37 kDa. The primary gene product exhibits an N-terminal leader sequence typical of lipoproteins, but palmitoylation of Tpc could not be demonstrated. The ribosomal binding site of tpc is immediately downstream of the translational stop codon of the folC gene coding for an enzyme involved in folic acid biosynthesis and one-carbon metabolism. The tpc gene is probably co-transcribed from the folC promoter and a promoter located within the folC gene. The latter promoter sequence shares significant homology with E. coli gearbox consensus promoters. All three mutant phenotypes, i.e. the cell separation defect, the transformation deficiency and the defect in cell invasion can be restored by complementation of the mutant with an intact tpc gene. To some extent the tcp phenotype is reminiscent of iap in Listeria, lytA in Streptococcus pneumoniae and lyt in Bacillus subtilis, all of which are considered to represent murein hydrolase defects. PMID:8730876

  7. Dysregulation of lysosomal morphology by pathogenic LRRK2 is corrected by TPC2 inhibition

    PubMed Central

    Hockey, Leanne N.; Kilpatrick, Bethan S.; Eden, Emily R.; Lin-Moshier, Yaping; Brailoiu, G. Cristina; Brailoiu, Eugen; Futter, Clare E.; Schapira, Anthony H.; Marchant, Jonathan S.; Patel, Sandip

    2015-01-01

    ABSTRACT Two-pore channels (TPCs) are endolysosomal ion channels implicated in Ca2+ signalling from acidic organelles. The relevance of these ubiquitous proteins for human disease, however, is unclear. Here, we report that lysosomes are enlarged and aggregated in fibroblasts from Parkinson disease patients with the common G2019S mutation in LRRK2. Defects were corrected by molecular silencing of TPC2, pharmacological inhibition of TPC regulators [Rab7, NAADP and PtdIns(3,5)P2] and buffering local Ca2+ increases. NAADP-evoked Ca2+ signals were exaggerated in diseased cells. TPC2 is thus a potential drug target within a pathogenic LRRK2 cascade that disrupts Ca2+-dependent trafficking in Parkinson disease. PMID:25416817

  8. Scintillation photon detection in liquid argon at the Long-Baseline Neutrino Facility

    NASA Astrophysics Data System (ADS)

    Howard, Bruce; Adams, Brice; Baugh, Brian; Buchanan, Norm; Bugel, Len; Conrad, Janet; Davis, Ronald; Gebhard, Mark; Lang, Michael; Miner, Bill; Mufson, Stuart; Musser, James; Pordes, Stephen; Rebel, Brian; Smith, Paul; Toups, Matt; Urheim, Jon; Warner, David; Wongjirad, Taritree; Whittington, Denver

    2015-04-01

    The proposed Long-Baseline Neutrino Facility (LBNF) aims to answer outstanding questions relating to neutrino physics and other phenomena, such as proton decay and supernova neutrinos. The proposed far detector design calls for a multi-kiloton liquid argon time-projection chamber at a long baseline. In addition to its utility as a target material, liquid argon scintillates in the far UV, providing further physics information and serving as a trigger for non-beam events. The photon detection system in development for the LBNF far detector includes a mechanism for capturing and transporting the light, a method to detect the photons (silicon photomultipliers), and the necessary readout electronics. Testing in liquid argon has occurred at the ``TallBo'' facility at Fermilab to characterize and compare the performance of these systems. In this talk, we present the details of these photon detection systems and the latest results of testing.

  9. Peach Bottom Turbine Trip Simulations with RETRAN Using INER/TPC BWR Transient Analysis Method

    SciTech Connect

    Kao Lainsu; Chiang, Show-Chyuan

    2005-03-15

    The work described in this paper is benchmark calculations of pressurization transient turbine trip tests performed at the Peach Bottom boiling water reactor (BWR). It is part of an overall effort in providing qualification basis for the INER/TPC BWR transient analysis method developed for the Kuosheng and Chinshan plants. The method primarily utilizes an advanced system thermal hydraulics code, RETRAN02/MOD5, for transient safety analyses. Since pressurization transients would result in a strong coupling effect between core neutronic and system thermal hydraulics responses, the INER/TPC method employs the one-dimensional kinetic model in RETRAN with a cross-section data library generated by the Studsvik-CMS code package for the transient calculations. The Peach Bottom Turbine Trip (PBTT) tests, including TT1, TT2, and TT3, have been successfully performed in the plant and assigned as standards commonly for licensing method qualifications for years. It is an essential requirement for licensing purposes to verify integral capabilities and accuracies of the codes and models of the INER/TPC method in simulating such pressurization transients. Specific Peach Bottom plant models, including both neutronics and thermal hydraulics, are developed using modeling approaches and experiences generally adopted in the INER/TPC method. Important model assumptions in RETRAN for the PBTT test simulations are described in this paper. Simulation calculations are performed with best-estimated initial and boundary conditions obtained from plant test measurements. The calculation results presented in this paper demonstrate that the INER/TPC method is capable of calculating accurately the core and system transient behaviors of the tests. Excellent agreement, both in trends and magnitudes between the RETRAN calculation results and the PBTT measurements, shows reliable qualifications of the codes/users/models involved in the method. The RETRAN calculated peak neutron fluxes of the PBTT

  10. Microstructures and Argon age dating

    NASA Astrophysics Data System (ADS)

    Forster, Marnie; Fitz Gerald, John; Lister, Gordon

    2010-05-01

    Microstructures can be dated using 40Ar/39Ar geochronology, but certain conditions apply. In particular the nature of the physical processes that took place during development of need be identified, and the pattern of gas release (and/or retention) during their evolution in nature, and subsequently in the mass spectrometer, during the measurement process. Most researchers cite temperature as the sole variable of importance. There is a belief that there is a single "closure temperature" or a "closure interval" above which the mineral is incapable of retaining radiogenic argon. This is a false conception. Closure is practically relevant only in circumstances that see a rock cooled relatively rapidly from temperatures that were high enough to prevent significant accumulation of radiogenic argon, to temperatures below which there is insignificant loss of radiogenic argon through the remainder of the geological history. These conditions accurately apply only to a limited subset - for example to rocks that cool rapidly from a melt and thereafter remain at or close to the Earth's surface, without subsequent ingress of fluids that would cause alteration and modification of microstructure. Some minerals in metamorphic rocks might display such "cooling ages" but in principle these data are difficult to interpret since they depend on the rate of cooling, the pressures that applied, and the subsequent geological history. Whereas the science of "cooling ages" is relatively well understood, the science of the Argon Partial Retention Zone is in its infancy. In the Argon PRZ it is evident that ages should (and do) show a strong correlation with microstructure. The difficulty is that, since diffusion of Argon is simultaneously multi-path and multi-scale, it is difficult to directly interrogate the distinct reservoirs that store gas populations and thus the age information that can be recorded as to the multiple events during the history of an individual microstructure. Laser

  11. Darkside-20k: A 20 ton Liquid Argon Dark Matter Experiment

    NASA Astrophysics Data System (ADS)

    Back, Henning; Darkside-20k Collaboration

    2016-03-01

    The Darkside-20k detector is the next step in the Darkside dark matter search program at the Laboratori Nazionali del Gran Sasso in Italy. The Darkside detectors have grown in fiducial mass starting with 10kg in Darkside10, to 50 kg in Darkside50, and finally a proposed 20,000 kg fiducial mass, Darkside20k. The Darkside detectors are dual-phase argon TPCs that combine the very powerful scintillation pulse-shape analysis and ionization information to discriminate against background events. Two unique aspects to the Darkside program is the use of an external neutron veto based on borated liquid scintillator, and the use of low radioactivity argon from underground sources as the target. Argon from the atmosphere has an 39Ar activity of 1Bq/kg, which would be the limiting background, but the underground argon is essentially free of 39Ar. Additionally, the detector is placed in a water Cherenkov muon veto. Combining all these techniques allows Darkside-20k to achieve a background-free 100 t-yr exposure accumulated in a 5 yr run. Darkside-20k is expected to start operations in 2020 with data taking starting in 2021, and will be sensitive to WIMP-nucleon interaction cross sections of 1×10-47 cm2 (1x10-46 cm2) for WIMPs of 1 TeV/c2 (10 TeV/c2) mass.

  12. Penning transfer in argon-based gas mixtures

    NASA Astrophysics Data System (ADS)

    Şahin, Ö.; Tapan, İ.; Özmutlu, E. N.; Veenhof, R.

    2010-05-01

    Penning transfers, a group of processes by which excitation energy is used to ionise the gas, increase the gas gain in some detectors. Both the probability that such transfers occur and the mechanism by which the transfer takes place, vary with the gas composition and pressure. With a view to developing a microscopic electron transport model that takes Penning transfers into account, we use this dependence to identify the transfer mechanisms at play. We do this for a number of argon-based gas mixtures, using gain curves from the literature.

  13. Electron avalanches in liquid argon mixtures

    SciTech Connect

    Kim, J.G.; Dardin, S.M.; Kadel, R.W.; Kadyk, J.A.; Wenzel, W.B.; Peskov, V.

    2004-03-19

    We have observed stable avalanche gain in liquid argon when mixed with small amounts of xenon in the high electric field (>7 MV/cm) near the point of a chemically etched needle in a point-plane geometry. We identify two gain mechanisms, one pressure dependent, and the other independent of the applied pressure. We conclude that the pressure dependent signals are from avalanche gain in gas bubbles at the tip of the needle, while the pressure independent pulses are from avalanche gain in liquid. We measure the decay time spectra of photons from both types of avalanches. The decay times from the pressure dependent pulses decrease (increase) with the applied pressure (high voltage), while the decay times from the pressure independent pulses are approximately independent of pressure or high voltage. For our operating conditions, the collected charge distribution from avalanches is similar for 60 keV or 122 keV photon sources. With krypton additives, instead of Xe, we measure behavior consistent with only the pressure dependent pulses. Neon and TMS were also investigated as additives, and designs for practical detectors were tested.

  14. Electron avalanches in liquid argon mixtures

    NASA Astrophysics Data System (ADS)

    Kim, J. G.; Dardin, S. M.; Kadel, R. W.; Kadyk, J. A.; Peskov, V.; Wenzel, W. A.

    2004-12-01

    We have observed stable avalanche gain in liquid argon when mixed with small amounts of xenon (xe) in the high electric field ( >7 MV/cm) near the point of a chemically etched needle in a point-plane geometry. We identify two gain mechanisms, one pressure dependent, and the other independent of the applied pressure. We conclude that the pressure-dependent signals are from avalanche gain in gas bubbles at the tip of the needle, while the pressure-independent pulses are from avalanche gain in liquid. We measure the decay time spectra of photons from both types of avalanches. The decay times from the pressure-dependent pulses decrease (increase) with the applied pressure (high voltage), while the decay times from the pressure-independent pulses are approximately independent of pressure or high voltage. For our operating conditions, the collected charge distribution from avalanches is similar for 60 or 122 keV photon sources. With krypton additives, instead of Xe, we measure behavior consistent with only the pressure-dependent pulses. Neon and TMS were also investigated as additives, and designs for practical detectors were tested.

  15. SiPMs characterization and selection for the DUNE far detector photon detection system

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Maricic, J.

    2016-01-01

    The Deep Underground Neutrino Experiment (DUNE) together with the Long Baseline Neutrino Facility (LBNF) hosted at the Fermilab will provide a unique, world-leading program for the exploration of key questions at the forefront of neutrino physics and astrophysics. CP violation in neutrino flavor mixing is one of its most important potential discoveries. Additionally, the experiment will determine the neutrino mass hierarchy and precisely measure the neutrino mixing parameters which may potentially reveal new fundamental symmetries of nature. Moreover, the DUNE is also designed for the observation of nucleon decay and supernova burst neutrinos. The photon detection (PD) system in the DUNE far detector provides trigger for cosmic backgrounds, enhances supernova burst trigger efficiency and improves the energy resolution of the detector. The DUNE adopts the technology of liquid argon time projection chamber (LArTPC) that requires the PD sensors, silicon photomultipliers (SiPM), to be carefully chosen to not only work properly in LAr temperature, but also meet certain specifications for the life of the experiment. A comprehensive testing of SiPMs in cryostat is necessary since the datasheet provided by the manufactures in the market does not cover this temperature regime. This paper gives the detailed characterization results of SenSL C-Series 60035 SiPMs, including gain, dark count rate (DCR), cross-talk and after-pulse rate. Characteristic studies on SiPMs from other vendors are also discussed in order to avoid any potential problems associated with using a single source. Moreover, the results of the ongoing mechanical durability tests are shown for the current candidate, SenSL B/C-Series 60035 SiPMs.

  16. Final Report for the UNIVERSITY-BASED DETECTOR RESEARCH AND DEVELOPMENT FOR THE INTERNATIONAL LINEAR COLLIDER

    SciTech Connect

    Brau, James E

    2013-04-22

    The U.S Linear Collider Detector R&D program, supported by the DOE and NSF umbrella grants to the University of Oregon, made significant advances on many critical aspects of the ILC detector program. Progress advanced on vertex detector sensor development, silicon and TPC tracking, calorimetry on candidate technologies, and muon detection, as well as on beamline measurements of luminosity, energy, and polarization.

  17. ARAPUCA a new device for liquid argon scintillation light detection

    NASA Astrophysics Data System (ADS)

    Machado, A. A.; Segreto, E.

    2016-02-01

    We present a totally innovative device for the detection of liquid argon scintillation light, that has been named ARAPUCA (Argon R&D Advanced Program at UniCAmp). It is composed of a passive light collector and of active devices. The latters are standard SiPMs that operate at liquid argon temperature, while the passive collector is based on a new technology, never explored in this field before. It is a photon trap, that allows to collect light with extremely high efficiency. The total detection efficiency of the device can be tuned by modifying the ratio between the area of the active devices (SiPM) and the area of the optical window. For example, it will allow to reach a detection efficiency at the level of 1% on a surface of 50 × 50 cm2 with an active coverage of 2 × 2 cm2 (two/three large area SiPM). It is also a cheap device, since the major part of its cost is represented by the active devices. For these reason this appears to be the ideal device for scintillation light detection in large Time Projection Chambers. With appropriate modifications it can be used also in next generation Dark Matter detectors.

  18. Liquid Argon Calorimetry for ATLAS

    NASA Astrophysics Data System (ADS)

    Robinson, Alan

    2008-05-01

    This summer, the largest collaborative physics project since the Manhattan project will go online. One of four experiments for the Large Hadron Collider at CERN in Geneva, ATLAS, employs over 2000 people. Canadians have helped design, construct, and calibrate the liquid argon calorimeters for ATLAS to capture the products of the high energy collisions produced by the LHC. From an undergraduate's perspective, explore how these calorimeters are made to handle their harsh requirement. From nearly a billion proton-proton collisions a second, physicists hope to discover the Higgs boson and other new fundamental particles.

  19. Measuring Cross-Section and Estimating Uncertainties with the fissionTPC

    SciTech Connect

    Bowden, N.; Manning, B.; Sangiorgio, S.; Seilhan, B.

    2015-01-30

    The purpose of this document is to outline the prescription for measuring fission cross-sections with the NIFFTE fissionTPC and estimating the associated uncertainties. As such it will serve as a work planning guide for NIFFTE collaboration members and facilitate clear communication of the procedures used to the broader community.

  20. Performance Evaluation of the COBRA GEM for the Application of the TPC

    NASA Astrophysics Data System (ADS)

    Terasaki, Kohei; Hamagaki, Hideki; Gunji, Taku; Yamaguchi, Yorito

    2014-09-01

    Suppression of the back-drifting ions from avalanche region to drift space (IBF: Ion Backflow) is the key for a Time Projection Chamber (TPC) since IBF easily distorts the drift field. To suppress IBF, Gating Grid system is widely used for the TPC but this limits the data taking rate. Gas Electron Multiplier (GEM) has advantages in the reduction of IBF and high rate capability. By adopting GEM, it is possible to run a TPC continuously under high rate and high multiplicity conditions. Motivated by the study of IBF reduction for RICH with Thick COBRA, which has been developed by F. A. Amero et al., we developed COBRA GEMs for the application of a TPC. With a stack configuration, IBF reaches about 0.1 ~ 0.5%, which is ×5--10 better IBF than the standard GEMs. However, the measured energy resolution with COBRA is 20% (σ) and this is much worse than the resolution with standard GEMs. Measurement of long-time stability of gain indicates that gain of COBRA varies significantly due to charging up effect. Simulation studies based on Garfield++ are performed for understanding quantitatively the reasons of worse energy resolution and instability of gain. In this presentation, we will report the simulation studies together with the measured performance of the COBRA GEM.

  1. Precise Nuclear Data Measurements Possible with the NIFFTE fissionTPC for Advanced Reactor Designs

    NASA Astrophysics Data System (ADS)

    Towell, Rusty; Niffte Collaboration

    2015-10-01

    The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) Collaboration has applied the proven technology of Time Projection Chambers (TPC) to the task of precisely measuring fission cross sections. With the NIFFTE fission TPC, precise measurements have been made during the last year at the Los Alamos Neutron Science Center from both U-235 and Pu-239 targets. The exquisite tracking capabilities of this device allow the full reconstruction of charged particles produced by neutron beam induced fissions from a thin central target. The wealth of information gained from this approach will allow systematics to be controlled at the level of 1%. The fissionTPC performance will be presented. These results are critical to the development of advanced uranium-fueled reactors. However, there are clear advantages to developing thorium-fueled reactors such as Liquid Fluoride Thorium Reactors over uranium-fueled reactors. These advantages include improved reactor safety, minimizing radioactive waste, improved reactor efficiency, and enhanced proliferation resistance. The potential for using the fissionTPC to measure needed cross sections important to the development of thorium-fueled reactors will also be discussed.

  2. Performance of the fissionTPC and the Potential to Advance the Thorium Fuel Cycle

    NASA Astrophysics Data System (ADS)

    Towell, Rusty; Niffte Collaboration

    2014-09-01

    The NIFFTE fission Time Projection Chamber (fissionTPC) is a powerful tool that is being developed to take precision measurements of neutron-induced fission cross sections of transuranic elements. During the last run at the Los Alamos Neutron Science Center (LANSCE) the fully instrumented TPC took data for the first time. The exquisite tracking capabilities of this device allow the full reconstruction of charged particles produced by neutron beam induced fissions from a thin central target. The wealth of information gained from this approach will allow cross section systematics to be controlled at the level of 1%. The fissionTPC performance from this run will be shared. These results are critical to the development of advanced uranium-fueled reactors. However, there are clear advantages to developing thorium-fueled reactors including the abundance of thorium verses uranium, minimizing radioactive waste, improved reactor safety, and enhanced proliferation resistance. The potential for using the fissionTPC to measure needed cross sections important to the development of thorium fueled nuclear reactors will also be discussed.

  3. A study of dielectric breakdown along insulators surrounding conductors in liquid argon

    SciTech Connect

    Lockwitz, Sarah; Jostlein, Hans

    2015-06-12

    High voltage breakdown in liquid argon is an important concern in the design of liquid argon time projection chambers, which are often used as neutrino and dark matter detectors. We have made systematic measurements of breakdown voltages in liquid argon along insulators surrounding negative rod electrodes where the breakdown is initiated at the anode. The measurements were performed in an open cryostat filled with commercial grade liquid argon exposed to air, and not the ultra-pure argon required for electron drift. While not addressing all high voltage concerns in liquid argon, these measurements have direct relevance to the design of high voltage feedthroughs especially for averting the common problem of flash-over breakdown. The purpose of these tests is to understand the effects of materials, of breakdown path length, and of surface topology for this geometry and setup. We have found that the only material-specific effects are those due to their permittivity. We have found that the breakdown voltage has no dependence on the length of the exposed insulator. Lastly, a model for the breakdown mechanism is presented that can help inform future designs.

  4. A study of dielectric breakdown along insulators surrounding conductors in liquid argon

    DOE PAGESBeta

    Lockwitz, Sarah; Jostlein, Hans

    2016-03-22

    High voltage breakdown in liquid argon is an important concern in the design of liquid argon time projection chambers, which are often used as neutrino and dark matter detectors. We have made systematic measurements of breakdown voltages in liquid argon along insulators surrounding negative rod electrodes where the breakdown is initiated at the anode. The measurements were performed in an open cryostat filled with commercial grade liquid argon exposed to air, and not the ultra-pure argon required for electron drift. While not addressing all high voltage concerns in liquid argon, these measurements have direct relevance to the design of highmore » voltage feedthroughs especially for averting the common problem of flash-over breakdown. The purpose of these tests is to understand the effects of materials, of breakdown path length, and of surface topology for this geometry and setup. We have found that the only material-specific effects are those due to their permittivity. We have found that the breakdown voltage has no dependence on the length of the exposed insulator. Lastly, a model for the breakdown mechanism is presented that can help inform future designs.« less

  5. Results from the first use of low radioactivity argon in a dark matter search

    NASA Astrophysics Data System (ADS)

    Agnes, P.; Agostino, L.; Albuquerque, I. F. M.; Alexander, T.; Alton, A. K.; Arisaka, K.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; Bottino, B.; Brigatti, A.; Brodsky, J.; Budano, F.; Bussino, S.; Cadeddu, M.; Cadonati, L.; Cadoni, M.; Calaprice, F.; Canci, N.; Candela, A.; Cao, H.; Cariello, M.; Carlini, M.; Catalanotti, S.; Cavalcante, P.; Chepurnov, A.; Cocco, A. G.; Covone, G.; Crippa, L.; D'Angelo, D.; D'Incecco, M.; Davini, S.; De Cecco, S.; De Deo, M.; De Vincenzi, M.; Derbin, A.; Devoto, A.; Di Eusanio, F.; Di Pietro, G.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Forster, G.; Franco, D.; Gabriele, F.; Galbiati, C.; Giganti, C.; Goretti, A. M.; Granato, F.; Grandi, L.; Gromov, M.; Guan, M.; Guardincerri, Y.; Hackett, B. R.; Herner, K.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; James, I.; Jollet, C.; Keeter, K.; Kendziora, C. L.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Kubankin, A.; Li, X.; Lissia, M.; Lombardi, P.; Luitz, S.; Ma, Y.; Machulin, I. N.; Mandarano, A.; Mari, S. M.; Maricic, J.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Meyers, P. D.; Miletic, T.; Milincic, R.; Montanari, D.; Monte, A.; Montuschi, M.; Monzani, M.; Mosteiro, P.; Mount, B. J.; Muratova, V. N.; Musico, P.; Napolitano, J.; Nelson, A.; Odrowski, S.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Pelczar, K.; Pelliccia, N.; Perasso, S.; Pocar, A.; Pordes, S.; Pugachev, D. A.; Qian, H.; Randle, K.; Ranucci, G.; Razeto, A.; Reinhold, B.; Renshaw, A. L.; Romani, A.; Rossi, B.; Rossi, N.; Rountree, D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Sangiorgio, S.; Savarese, C.; Segreto, E.; Semenov, D. A.; Shields, E.; Singh, P. N.; Skorokhvatov, M. D.; Smirnov, O.; Sotnikov, A.; Stanford, C.; Suvorov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Trinchese, P.; Unzhakov, E. V.; Vishneva, A.; Vogelaar, B.; Wada, M.; Walker, S.; Wang, H.; Wang, Y.; Watson, A. W.; Westerdale, S.; Wilhelmi, J.; Wojcik, M. M.; Xiang, X.; Xu, J.; Yang, C.; Yoo, J.; Zavatarelli, S.; Zec, A.; Zhong, W.; Zhu, C.; Zuzel, G.; DarkSide Collaboration

    2016-04-01

    Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using a two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain 39Ar at a level reduced by a factor (1.4 ±0.2 )×103 relative to atmospheric argon. We report a background-free null result from (2616 ±43 ) kg d of data, accumulated over 70.9 live days. When combined with our previous search using an atmospheric argon, the 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section, based on zero events found in the WIMP search regions, is 2.0 ×10-44 cm2 (8.6 ×10-44 cm2 , 8.0 ×10-43 cm2 ) for a WIMP mass of 100 GeV /c2 (1 TeV /c2 , 10 TeV /c2 ).

  6. Results from the first use of low radioactivity argon in a dark matter search

    DOE PAGESBeta

    Agnes, P.

    2016-04-08

    Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar-39 at a level reduced by a factor (1.4 +- 0.2) x 103 relative to atmospheric argon. We report a background-free null result from (2616 +- 43) kg d of data, accumulatedmore » over 70.9 live-days. When combined with our previous search using an atmospheric argon, the 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section based on zero events found in the WIMP search regions, is 2.0 x 10-44 cm2 (8.6 x 10-44 cm2, 8.0 x 10-43 cm2) for a WIMP mass of 100 GeV/c2 (1 TeV/c2 , 10 TeV/c2).« less

  7. Low Radioactivity Argon Dark Matter Search Results from the DarkSide-50 Experiment

    SciTech Connect

    Agnes, P.

    2015-10-02

    Our DarkSide-50 dark matter search reports the first results obtained using a target of lowradioactivity argon extracted from underground sources. The experiment is located at the Laboratori Nazionali del Gran Sasso and uses a two-phase time projection chamber as a detector. A total of 155 kg of low radioactivity argon has been obtained, and we have determined that underground argon is depleted in 39Ar by a factor (1.4 ±0.2) x 103 relative to atmospheric argon. The underground argon was also found to contain (2.05 ± 0.13)mBq=kg of 85Kr. We also found no evidence for dark matter in the form of WIMPs in 70.9 live-days of data with a fiducial mass of (36.9 ± 0.6) kg. When combined with our preceding search with an atmospheric argon target, we set a 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section of 2.0 x 10-44 cm2 (8.6 x 10-44 cm2, 8.0 x 10-43 cm2) for a WIMP mass of 100 GeV=c2 (1TeV=c2, 10TeV=c2).

  8. Results from the first use of low radioactivity argon in a dark matter search

    DOE PAGESBeta

    Agnes, P.

    2016-04-08

    Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using a two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar39 at a level reduced by a factor (1.4 ± 0.2) × 103 relative to atmospheric argon. Here, we report a background-free null result from (2616 ± 43) kg d ofmore » data, accumulated over 70.9 live days. When combined with our previous search using an atmospheric argon, the 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section, based on zero events found in the WIMP search regions, is 2.0 × 10–44 cm2 (8.6 × 10–44 cm2, 8.0 × 10–43 cm2) for a WIMP mass of 100 GeV/c2 (1 TeV/c2, 10 TeV/c2).« less

  9. DarkSide-50 WIMP search results with low radioactivity argon

    NASA Astrophysics Data System (ADS)

    Xiang, Xin; DarkSide Collaboration

    2016-03-01

    Located at the Laboratori Nazionali del Gran Sasso, DarkSide-50 is the first physics detector of the DarkSide dark matter search program. The experiment features a dual-phase Time Projection Chamber as the WIMP detector, surrounded by an organic liquid-scintillator neutron veto and a water-Cherenkov muon detector. We report the results from the first use of low radioactivity argon extracted from underground sources in a dark matter search. We have determined that underground argon is depleted in 39Ar by a factor (1 . 4 +/- 0 . 2) ×103 relative to atmospheric argon whose 39Ar activity is 1 bq/kg. The underground argon is also found to contain (2 . 05 +/- 0 . 13) mBq/kg of 85Kr. We find no evidence for dark matter in the form of WIMPs in 70.9 live-days of data with a fiducial mass of (36 . 9 +/- 0 . 6) kg. When combined with our preceding search with an atmospheric argon target, we set a 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section of 2 . 0 ×10-44 cm2 (8 . 6 ×10-44 cm2, 8 . 0 ×10-43 cm2) for a WIMP mass of 100 GeV/c2 (1 TeV/c2, 10 TeV/c2). DS-50 will continue dark matter search with the underground argon target for a total of 3 years. See also the DS-50 presentations by E. Edkins and G. Koh.

  10. Liquid argon calorimetry for the SSC

    SciTech Connect

    Gordon, H.A.

    1990-01-01

    Liquid argon calorimetry is a mature technique. However, adapting it to the challenging environment of the SSC requires a large amount of R D. The advantages of the liquid argon approach are summarized and the issues being addressed by the R D program are described. 18 refs.

  11. Argon purge gas cooled by chill box

    NASA Technical Reports Server (NTRS)

    Spiro, L. W.

    1966-01-01

    Cooling argon purge gas by routing it through a shop-fabricated chill box reduces charring of tungsten inert gas torch head components. The argon gas is in a cooled state as it enters the torch and prevents buildup of char caused by the high concentrations of heat in the weld area during welding operations.

  12. Neutrino-Argon Interaction with GENIE Event Generator

    NASA Astrophysics Data System (ADS)

    Chesneanu, Daniela

    2010-11-01

    Neutrinos are very special particles, have only weak interactions, except gravity, and are produced in very different processes in Nuclear and Particle Physics. Neutrinos are, also, messengers from astrophysical objects, as well as relics from Early Universe. Therefore, its can give us information on processes happening in the Universe, during its evolution, which cannot be studied otherwise. The underground instrumentation including a variety of large and very large detectors, thanks to technical breakthroughs, have achieved new fundamental results like the solution of the solar neutrino puzzle and the evidence for Physics beyond the Standard Model of elementary interactions in the neutrino sector with non-vanishing neutrino masses and lepton flavour violation. Two of the LAGUNA (Large Apparatus studying Grand Unification and Neutrino Astrophysics) detectors, namely: GLACIER (Giant Liquid Argon Charge Imaging ExpeRiment) [1] and LENA (Low Energy Neutrino Astrophysics) [2] could be emplaced in ``Unirea'' salt mine from Slănic-Prahova, Romania. A detailed analysis of the conditions and advantages is necessary. A few results have been presented previously [3]. In the present work, we propose to generate events and compute the cross sections for interactions between neutrino and Argon-40, to estimate possible detection performances and event types. For doing this, we use the code GENIE (G_enerates E_vents for N_eutrino I_nteraction E_xperiments) [4]. GENIE Code is an Object-Oriented Neutrino MC Generator supported and developed by an international collaboration of neutrino interaction experts.

  13. Neutrino-Argon Interaction with GENIE Event Generator

    SciTech Connect

    Chesneanu, Daniela

    2010-11-24

    Neutrinos are very special particles, have only weak interactions, except gravity, and are produced in very different processes in Nuclear and Particle Physics. Neutrinos are, also, messengers from astrophysical objects, as well as relics from Early Universe. Therefore, its can give us information on processes happening in the Universe, during its evolution, which cannot be studied otherwise. The underground instrumentation including a variety of large and very large detectors, thanks to technical breakthroughs, have achieved new fundamental results like the solution of the solar neutrino puzzle and the evidence for Physics beyond the Standard Model of elementary interactions in the neutrino sector with non-vanishing neutrino masses and lepton flavour violation.Two of the LAGUNA(Large Apparatus studying Grand Unification and Neutrino Astrophysics) detectors, namely: GLACIER (Giant Liquid Argon Charge Imaging ExpeRiment) and LENA (Low Energy Neutrino Astrophysics) could be emplaced in 'Unirea' salt mine from Slanic-Prahova, Romania. A detailed analysis of the conditions and advantages is necessary. A few results have been presented previously. In the present work, we propose to generate events and compute the cross sections for interactions between neutrino and Argon-40, to estimate possible detection performances and event types. For doing this, we use the code GENIE(G lowbar enerates E lowbar vents for N lowbar eutrino I lowbar nteraction E lowbar xperiments). GENIE Code is an Object-Oriented Neutrino MC Generator supported and developed by an international collaboration of neutrino interaction experts.

  14. LArGe: active background suppression using argon scintillation for the Gerda 0ν β β -experiment

    NASA Astrophysics Data System (ADS)

    Agostini, M.; Barnabé-Heider, M.; Budjáš, D.; Cattadori, C.; Gangapshev, A.; Gusev, K.; Heisel, M.; Junker, M.; Klimenko, A.; Lubashevskiy, A.; Pelczar, K.; Schönert, S.; Smolnikov, A.; Zuzel, G.

    2015-10-01

    LArGe is a Gerda low-background test facility to study novel background suppression methods in a low-background environment, for future application in the Gerda experiment. Similar to Gerda, LArGe operates bare germanium detectors submersed into liquid argon (1 m^3, 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to Gerda. Suppression factors of a few times 10^3 have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12-4.6)× 10^{-2} cts/(keV kg year) (90 % C.L.), which is at the level of Gerda Phase I. Furthermore, for the first time we monitor the natural ^{42}Ar abundance (parallel to Gerda), and have indication for the 2ν β β -decay in natural germanium. These results show the effectivity of an active liquid argon veto in an ultra-low background environment. As a consequence, the implementation of a liquid argon veto in Gerda Phase II is pursued.

  15. A G/NARRLI Effort. Measuring the Ionization Yield of Low-Energy Nuclear Recoils in Liquid Argon

    SciTech Connect

    Joshi, Tenzing Henry Yatish

    2014-01-01

    Liquid argon has long been used for particle detection due to its attractive drift properties, ample abundance, and reasonable density. The response of liquid argon to lowenergy O(102 -1044 eV) interactions is, however, largely unexplored. Weakly interacting massive particles such as neutrinos and hypothetical dark-matter particles (WIMPs) are predicted to coherently scatter on atomic nuclei, leaving only an isolated low-energy nuclear recoil as evidence. The response of liquid argon to low-energy nuclear recoils must be studied to determine the sensitivity of liquid argon based detectors to these unobserved interactions. Detectors sensitive to coherent neutrino-nucleus scattering may be used to monitor nuclear reactors from a distance, to detect neutrinos from supernova, and to test the predicted behavior of neutrinos. Additionally, direct detection of hypothetical weakly interacting dark matter would be a large step toward understanding the substance that accounts for nearly 27% of the universe. In this dissertation I discuss a small dual-phase (liquid-gas) argon proportional scintillation counter built to study the low-energy regime and several novel calibration and characterization techniques developed to study the response of liquid argon to low-energy O(102 -104 eV) interactions.

  16. Search for a QGP with a TPC spectrometer, and QGP signals predicted by new event generator

    SciTech Connect

    Lindenbaum, S.J.

    1988-12-08

    The BNL/CCNY/Johns Hopkins/Rice Collaboration has developed and successfully tested a TPC Magnetic Spectrometer to search for OGP signals produced by ion beams at AGS. Test data with 14.5 GeV/c /times/ A Oxygen ions incident on a Pb target has been obtained. These include a 78-prong nuclear interaction in the MPS magnet which was pattern recognized with an efficiency approx.75%. A cascade and plasma event generator has also been developed, the predictions of which are used to illustrate how our technique can detect possible plasma signals at AGS and RHIC. A 4..pi.. tracking TPC magnetic spectrometer has been proposed for RHIC. The new event generator predicts striking central rapidity bump QGP signals at RHIC for p, /bar p/, ..pi../sup +-/, K/sup +-/, etc., produced by 100 GeV/c /times/ A Au on Au collisions and these are presented. 2 refs., 13 figs., 1 tab.

  17. Track reconstruction based on Hough-transform for nTPC

    NASA Astrophysics Data System (ADS)

    Niu, Li-Bo; Li, Yu-Lan; Huang, Meng; He, Bin; Li, Yuan-Jing

    2014-12-01

    A GEM-TPC prototype, which will be used as a fast neutron spectrometer based on the recoil proton method, is designed and being constructed in Tsinghua University. In order to derive the recoil angle of the recoil proton, tracks of recoil proton in the TPC sensitive volume must be reconstructed. An algorithm based on Hough-transform for track finding and least square method for track fitting was developed in this paper. Based on the Monte Carlo simulation data given by Geant4, a detailed track reconstruction process was introduced and the spectrum of induced fast neutron was derived here. The results show that the algorithm was effective and high-performance. With the recoil angle of the proton less than 30°, a 4.4% FWHM neutron energy resolution was derived for 5 MeV induced fast neutron, and the detection efficiency was about 2×10-4.

  18. Two-pore Channels Enter the Atomic Era: Structure of Plant TPC Revealed.

    PubMed

    Patel, Sandip; Penny, Christopher J; Rahman, Taufiq

    2016-06-01

    Two-pore channels (TPCs) are intracellular Ca(2+)-permeable ion channels that are expressed on acidic Ca(2+) stores. They are co-regulated by voltage and Ca(2+) in plant vacuoles and by the second messenger NAADP in animal endo-lysosomes. Two new studies of plant TPC structures reveal essential features of their architecture and provide mechanistic insight into their workings. PMID:27156118

  19. TPC2 mediates new mechanisms of platelet dense granule membrane dynamics through regulation of Ca2+ release

    PubMed Central

    Ambrosio, Andrea L.; Boyle, Judith A.; Di Pietro, Santiago M.

    2015-01-01

    Platelet dense granules (PDGs) are acidic calcium stores essential for normal hemostasis. They develop from late endosomal compartments upon receiving PDG-specific proteins through vesicular trafficking, but their maturation process is not well understood. Here we show that two-pore channel 2 (TPC2) is a component of the PDG membrane that regulates PDG luminal pH and the pool of releasable Ca2+. Using a genetically encoded Ca2+ biosensor and a pore mutant TPC2, we establish the function of TPC2 in Ca2+ release from PDGs and the formation of perigranular Ca2+ nanodomains. For the first time, Ca2+ spikes around PDGs—or any organelle of the endolysosome family—are visualized in real time and revealed to precisely mark organelle “kiss-and-run” events. Further, the presence of membranous tubules transiently connecting PDGs is revealed and shown to be dramatically enhanced by TPC2 in a mechanism that requires ion flux through TPC2. “Kiss-and-run” events and tubule connections mediate transfer of membrane proteins and luminal content between PDGs. The results show that PDGs use previously unknown mechanisms of membrane dynamics and content exchange that are regulated by TPC2. PMID:26202466

  20. Structure of Voltage-gated Two-pore Channel TPC1 from Arabidopsis thaliana

    PubMed Central

    Guo, Jiangtao; Zeng, Weizhong; Chen, Qingfeng; Lee, Changkeun; Chen, Liping; Yang, Yi; Cang, Chunlei; Ren, Dejian; Jiang, Youxing

    2015-01-01

    Two-pore channels (TPCs) contain two copies of a Shaker-like six-transmembrane (6-TM) domain in each subunit and are ubiquitously expressed in both animals and plants as organellar cation channels. Here, we present the first crystal structure of a vacuolar two-pore channel from Arabidopsis thaliana, AtTPC1, which functions as a homodimer. AtTPC1 activation requires both voltage and cytosolic Ca2+. Ca2+ binding to the cytosolic EF-hand domain triggers conformational changes coupled to the pair of pore-lining inner helices (IS6 helices) from the first 6-TM domains, whereas membrane potential only activates the second voltage-sensing domain (VSD2) whose conformational changes are coupled to the pair of inner helices (IIS6 helices) from the second 6-TM domains. Luminal Ca2+ or Ba2+ can modulate voltage activation by stabilizing VSD2 in the resting state and shifts voltage activation towards more positive potentials. Our Ba2+ bound AtTPC1 structure reveals a voltage sensor in the resting state, providing hitherto unseen structural insight into the general voltage-gating mechanism among voltage-gated channels. PMID:26689363

  1. Structure of the voltage-gated two-pore channel TPC1 from Arabidopsis thaliana.

    PubMed

    Guo, Jiangtao; Zeng, Weizhong; Chen, Qingfeng; Lee, Changkeun; Chen, Liping; Yang, Yi; Cang, Chunlei; Ren, Dejian; Jiang, Youxing

    2016-03-10

    Two-pore channels (TPCs) contain two copies of a Shaker-like six-transmembrane (6-TM) domain in each subunit and are ubiquitously expressed in both animals and plants as organellar cation channels. Here we present the crystal structure of a vacuolar two-pore channel from Arabidopsis thaliana, AtTPC1, which functions as a homodimer. AtTPC1 activation requires both voltage and cytosolic Ca(2+). Ca(2+) binding to the cytosolic EF-hand domain triggers conformational changes coupled to the pair of pore-lining inner helices from the first 6-TM domains, whereas membrane potential only activates the second voltage-sensing domain, the conformational changes of which are coupled to the pair of inner helices from the second 6-TM domains. Luminal Ca(2+) or Ba(2+) can modulate voltage activation by stabilizing the second voltage-sensing domain in the resting state and shift voltage activation towards more positive potentials. Our Ba(2+)-bound AtTPC1 structure reveals a voltage sensor in the resting state, providing hitherto unseen structural insight into the general voltage-gating mechanism among voltage-gated channels. PMID:26689363

  2. Safety related issues of the unexpected Argon release into the tunnel

    NASA Astrophysics Data System (ADS)

    Chorowski, M.; Malecha, Z. M.; Polinski, J.

    2015-12-01

    Modern physics laboratories require very large amounts of cryogenics fluids. Often the fluid must be transported along the tunnels or stored in the underground cavities. Currently, there are several ongoing projects where very large amounts of liquid (LAr) or gaseous Argon (GAr) will be used. One of them is a part of the LAGUNA-LBNO (Large Apparatus studying Grand Unification and Neutrino Astrophysics and Long Baseline Neutrino Oscillations) design study, where the GLACIER (Giant Liquid Argon Charge Imaging ExpeRiment) neutrino detector is considered. In order for it to properly operate, it requires the appropriate environment (it must be located in a deep, underground cavity) and approximately 150,000 tons of LAr. This huge amount of cryogen must be transported down the tunnel in cryogenic-tank trucks or by using pipelines. In both cases, there is a risk of uncontrolled LAr or GAr leakage into the tunnel, which can be dangerous for people, as well as during the installation itself. The presented work focuses on the risk analysis and consequences of unexpected Argon leakage into the tunnel. It shows the mathematical model and numerical tools which can serve to model the Argon cloud propagation, temperature distribution, and Oxygen deficiency. The results present a series of numerical experiments for Argon leakage into the tunnel with different external conditions (e.g. different ventilation regimes).

  3. Flexible Support Liquid Argon Heat Intercept

    SciTech Connect

    Rudland, D.L.; /Fermilab

    1987-05-18

    A device in the flexible support system for the Central Calorimeter is the Liquid Argon Heat Intercept. The purpose of this apparatus is to intercept heat outside the inner vessel so that bubbles do not form inside. If bubbles did happen to form inside the vessel, they would cause an electric arc between the read-out board and the absorption plates, thus destroying the pre-amplifier. Since this heat intercept is located in the center of the flexible support, it must also support the load of the Central Caloimeter. Figure 1 shows how the intercept works. The subcooled liquid argon is driven through a 1/4-inch x 0.049-inch w tube by hydrostatic pressure. the ambient heat boils the subcooled argon. The gaseous argon flows through the tube and is condensed at the top of the vessel by a 100 kW cooling coil. This process is rpesent in all four flexible support systems.

  4. Modelling of RF Discharge in Argon Plasma

    SciTech Connect

    Jelinek, P.; Virostko, P.; Hubicka, Z.; Bartos, P.

    2007-12-26

    An one-dimensional hybrid model of RF discharge in low-temperature argon plasma is presented in our paper. The hybrid model consists of two parts--particle model which simulates fast electrons while fluid model simulates slow electrons and positive argon ions. In the particle model the positions and velocities of fast electrons are calculated by means of deterministic Verlet algorithm while the collision processes are treated by the stochastic way. For the solution of fluid equations, for slow electrons and positive argon ions, the Scharfetter-Gummel exponential algorithm was used. Typical results of our calculations presented in this paper are total RF current and RF voltage waveforms on the planar substrate immersed into argon plasma. The next results which can be found here are the ion, electron and displacement current waveforms on the substrate. Especially, the knowledge of waveform of the ion current is very important for experimental physicists during the deposition of thin films.

  5. Clinical periodontics with the argon laser

    NASA Astrophysics Data System (ADS)

    Finkbeiner, R. L.

    1995-04-01

    The argon laser has proven to be a valuable tool for the thermodynamic debridement of the periodontal lesion, incisions and tissue fusion. Illustrations of clinical applications and discussion of laser parameters will be provided.

  6. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification. An argon gas analyzer is a device intended to measure the concentration of argon in a gas mixture to aid...

  7. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification. An argon gas analyzer is a device intended to measure the concentration of argon in a gas mixture to aid...

  8. Tracking Detectors in the STAR Experiment at RHIC

    NASA Astrophysics Data System (ADS)

    Wieman, Howard

    2015-04-01

    The STAR experiment at RHIC is designed to measure and identify the thousands of particles produced in 200 Gev/nucleon Au on Au collisions. This talk will focus on the design and construction of two of the main tracking detectors in the experiment, the TPC and the Heavy Flavor Tracker (HFT) pixel detector. The TPC is a solenoidal gas filled detector 4 meters in diameter and 4.2 meters long. It provides precise, continuous tracking and rate of energy loss in the gas (dE/dx) for particles at + - 1 units of pseudo rapidity. The tracking in a half Tesla magnetic field measures momentum and dE/dX provides particle ID. To detect short lived particles tracking close to the point of interaction is required. The HFT pixel detector is a two-layered, high resolution vertex detector located at a few centimeters radius from the collision point. It determines origins of the tracks to a few tens of microns for the purpose of extracting displaced vertices, allowing the identification of D mesons and other short-lived particles. The HFT pixel detector uses detector chips developed by the IPHC group at Strasbourg that are based on standard IC Complementary Metal-Oxide-Semiconductor (CMOS) technology. This is the first time that CMOS pixel chips have been incorporated in a collider application.

  9. Report on Advanced Detector Development

    SciTech Connect

    James K. Jewell

    2012-09-01

    Neutron, gamma and charged particle detection improvements are key to supporting many of the foreseen measurements and systems envisioned in the R&D programs and the future fuel cycle requirements, such as basic nuclear physics and data, modeling and simulation, reactor instrumentation, criticality safety, materials management and safeguards. This task will focus on the developmental needs of the FCR&D experimental programs, such as elastic/inelastic scattering, total cross sections and fission neutron spectra measurements, and will leverage a number of existing neutron detector development efforts and programs, such as those at LANL, PNNL, INL, and IAC as well as those at many universities, some of whom are funded under NE grants and contracts. Novel materials and fabrication processes combined with state-of-the-art electronics and computing provide new opportunities for revolutionary detector systems that will be able to meet the high precision needs of the program. This work will be closely coordinated with the Nuclear Data Crosscut. The Advanced Detector Development effort is a broadly-focused activity that supports the development of improved nuclear data measurements and improved detection of nuclear reactions and reactor conditions. This work supports the design and construction of large-scale, multiple component detectors to provide nuclear reaction data of unprecedented quality and precision. Examples include the Time Projection Chamber (TPC) and the DANCE detector at LANL. This work also supports the fabrication and end-user application of novel scintillator materials detection and monitoring.

  10. Accurate γ and MeV-electron track reconstruction with an ultra-low diffusion Xenon/TMA TPC at 10 atm

    NASA Astrophysics Data System (ADS)

    González-Díaz, Diego; Álvarez, V.; Borges, F. I. G.; Camargo, M.; Cárcel, S.; Cebrián, S.; Cervera, A.; Conde, C. A. N.; Dafni, T.; Díaz, J.; Esteve, R.; Fernandes, L. M. P.; Ferrario, P.; Ferreira, A. L.; Freitas, E. D. C.; Gehman, V. M.; Goldschmidt, A.; Gómez-Cadenas, J. J.; Gutiérrez, R. M.; Hauptman, J.; Hernando Morata, J. A.; Herrera, D. C.; Irastorza, I. G.; Labarga, L.; Laing, A.; Liubarsky, I.; Lopez-March, N.; Lorca, D.; Losada, M.; Luzón, G.; Marí, A.; Martín-Albo, J.; Martínez-Lema, G.; Martínez, A.; Miller, T.; Monrabal, F.; Monserrate, M.; Monteiro, C. M. B.; Mora, F. J.; Moutinho, L. M.; Muñoz Vidal, J.; Nebot-Guinot, M.; Nygren, D.; Oliveira, C. A. B.; Pérez, J.; Pérez Aparicio, J. L.; Querol, M.; Renner, J.; Ripoll, L.; Rodríguez, J.; Santos, F. P.; dos Santos, J. M. F.; Serra, L.; Shuman, D.; Simón, A.; Sofka, C.; Sorel, M.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F. C. A.; Villar, J. A.; Webb, R.; White, J. T.; Yahlali, N.; Azevedo, C.; Aznar, F.; Calvet, D.; Castel, J.; Ferrer-Ribas, E.; García, J. A.; Giomataris, I.; Gómez, H.; Iguaz, F. J.; Lagraba, A.; Le Coguie, A.; Mols, J. P.; Şahin, Ö.; Rodríguez, A.; Ruiz-Choliz, E.; Segui, L.; Tomás, A.; Veenhof, R.

    2015-12-01

    We report the performance of a 10 atm Xenon/trimethylamine time projection chamber (TPC) for the detection of X-rays (30 keV) and γ-rays (0.511-1.275 MeV) in conjunction with the accurate tracking of the associated electrons. When operated at such a high pressure and in 1%-admixtures, trimethylamine (TMA) endows Xenon with an extremely low electron diffusion (1.3 ± 0.13 mm - σ (longitudinal), 0.95 ± 0.20 mm - σ (transverse) along 1 m drift) besides forming a convenient 'Penning-Fluorescent' mixture. The TPC, that houses 1.1 kg of gas in its fiducial volume, operated continuously for 100 live-days in charge amplification mode. The readout was performed through the recently introduced microbulk Micromegas technology and the AFTER chip, providing a 3D voxelization of 8 mm × 8 mm × 1.2 mm for approximately 10 cm/MeV-long electron tracks. Resolution in energy (ε) at full width half maximum (R) inside the fiducial volume ranged from R = 14.6 % (30 keV) to R = 4.6 %(1.275 MeV). This work was developed as part of the R&D program of the NEXT collaboration for future detector upgrades in the search of the neutrino-less double beta decay (ββ 0 ν) in 136Xe, specifically those based on novel gas mixtures. Therefore we ultimately focus on the calorimetric and topological properties of the reconstructed MeV-electron tracks. In particular, the obtained energy resolution has been decomposed in its various contributions and improvements towards achieving the R = 1.4 %√{ 1 MeV / ε } levels obtained in small sensors are discussed.

  11. A Study of Nuclear Recoils in Liquid Argon Time Projection Chamber for the Direct Detection of WIMP Dark Matter

    SciTech Connect

    Cao, Huajie

    2014-11-01

    Robust results of WIMP direct detection experiments depend on rm understandings of nuclear recoils in the detector media. This thesis documents the most comprehensive study to date on nuclear recoils in liquid argon - a strong candidate for the next generation multi-ton scale WIMP detectors. This study investigates both the energy partition from nuclear recoil energy to secondary modes (scintillation and ionization) and the pulse shape characteristics of scintillation from nuclear recoils.

  12. Argon Collection And Purification For Proliferation Detection

    SciTech Connect

    Achey, R.; Hunter, D.

    2015-10-09

    In order to determine whether a seismic event was a declared/undeclared underground nuclear weapon test, environmental samples must be taken and analyzed for signatures that are unique to a nuclear explosion. These signatures are either particles or gases. Particle samples are routinely taken and analyzed under the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) verification regime as well as by individual countries. Gas samples are analyzed for signature gases, especially radioactive xenon. Underground nuclear tests also produce radioactive argon, but that signature is not well monitored. A radioactive argon signature, along with other signatures, can more conclusively determine whether an event was a nuclear test. This project has developed capabilities for collecting and purifying argon samples for ultra-low-background proportional counting. SRNL has developed a continuous gas enrichment system that produces an output stream containing 97% argon from whole air using adsorbent separation technology (the flow diagram for the system is shown in the figure). The vacuum swing adsorption (VSA) enrichment system is easily scalable to produce ten liters or more of 97% argon within twelve hours. A gas chromatographic separation using a column of modified hydrogen mordenite molecular sieve has been developed that can further purify the sample to better than 99% purity after separation from the helium carrier gas. The combination of these concentration and purification systems has the capability of being used for a field-deployable system for collecting argon samples suitable for ultra-low-background proportional counting for detecting nuclear detonations under the On-Site Inspection program of the CTBTO verification regime. The technology also has applications for the bulk argon separation from air for industrial purposes such as the semi-conductor industry.

  13. The readout driver (ROD) for the ATLAS liquid argon calorimeters

    NASA Astrophysics Data System (ADS)

    Efthymiopoulos, Ilias

    2001-04-01

    The Readout Driver (ROD) for the Liquid Argon calorimeter of the ATLAS detector is described. Each ROD module receives triggered data from 256 calorimeter cells via two fiber-optics 1.28 Gbit/s links with a 100 kHz event rate (25 kbit/event). Its principal function is to determine the precise energy and timing of the signal from discrete samples of the waveform, taken each period of the LHC clock (25 ns). In addition, it checks, histograms, and formats the digital data stream. A demonstrator system, consisting of a motherboard and several daughter-board processing units (PUs) was constructed and is currently used for tests in the lab. The design of this prototype board is presented here. The board offers maximum modularity and allows the development and testing of different PU designs based on today's leading integer and floating point DSPs.

  14. Development of a Photon Detection System in Liquid Argon for the Long-Baseline Neutrino Experiment

    NASA Astrophysics Data System (ADS)

    Whittington, Denver; Adams, Brice; Baptista, Brian; Baugh, Brian; Gebhard, Mark; Lang, Michael; Mufson, Stuart; Musser, James; Smith, Paul; Urheim, Jon

    2014-03-01

    The Long-Baseline Neutrino Experiment (LBNE) will be a premier facility for exploring long-standing questions about the boundaries of the standard model. Acting in concert with the liquid argon time projection chambers underpinning the far detector design, the LBNE photon detection system will capture ultraviolet scintillation light in order to provide valuable timing information for event reconstruction. The team at Indiana University is exploring a design based on acrylic waveguides coated with a wavelength-shifting compound, combined with silicon photomultipliers, to collect and record scintillation light from liquid argon. Large-scale tests of this design are being conducted at the ``TallBo'' liquid argon dewar facility at Fermilab, where performance studies with cosmic ray events are helping steer decisions for the final detector design. We present an overview of the design and function of this photon detection system and the latest results from the analysis of data collected during these tests. Photon Detector R&D Team at Indiana University.

  15. Argon isotopic zoning in mantle phlogopite

    SciTech Connect

    Phillips, D.; Onstott, T.C.

    1988-06-01

    Incremental-heating and laser-probe /sup 40/Ar//sup 39/Ar analyses were performed on phlogopite extracted from a garnet-lherzolite mantle nodule entrained by the Precambrian (1200 Ma) Premier kimberlite, South Africa. The spatial resolution of the laser probe has enabled the characterization of argon isotopic zoning in a single phlogopite grain. An apparent age contour map records lower ages (1.2 Ga) along grain margins and high apparent ages (up to 2.4 Ga) at the core. The latter ages are caused by excess argon contamination and subsequent partial diffusive loss, and have no age significance. Comparison with step-heating results indicates that argon spatial distributions inferred from in-vacuo step-heating experiments are, at best, grossly approximate. Variations in the laser-probe apparent ages were observed only laterally across the phlogopite cleavage surface, indicating that argon transport occurs preferentially along phlogopite cleavage planes. Age profiles, when modeled using one-dimensional radial geometry (cylindrical coordinates), do not conform to classical Fick's law diffusion, suggesting that the characteristic dimension of diffusion for argon in phlogopite may be highly variable within individual grains.

  16. Detectors for the Superconducting Super Collider, design concepts, and simulation

    SciTech Connect

    Gabriel, T.A.

    1989-01-01

    The physics of compensation calorimetry is reviewed in the light of the need of the Superconducting Super Collider (SSC) detectors. The four major detector types: liquid argon, scintillator, room temperature liquids, and silicon, are analyzed with respect to some of their strengths and weaknesses. Finally, general comments are presented which reflect the reliability of simulation code systems. 29 refs., 20 figs., 6 tabs.

  17. The search for cluster structure in 14C with the prototype AT-TPC

    NASA Astrophysics Data System (ADS)

    Fritsch, Adam Louis

    Certain light nuclei are known to have inherent cluster structuring, and the nature of the triple-alpha structure of carbon isotopes is a subject of active discussion in nuclear physics. Clustering in neutron-rich nuclei is of particular interest as such work could shed light on how neutrons affect alpha clustering, making 14C a logical candidate for such a study. Cluster structure in 14C was investigated at the University of Notre Dame with the prototype Active Target-Time Projection Chamber (AT-TPC). A 38.2 MeV secondary beam of 10Be was incident on an active target volume containing He:CO2 90:10 gas at 1 atm, in which trajectories of beam particles and reaction products were measured using the tracking capabilities of the prototype AT-TPC. Angular correlations of 10Be and alpha particles were used to reconstruct kinematics of scattering. Excitation functions and angular distributions were measured in both elastic and inelastic channels, which unraveled a number of resonances in 14C. Spin-parity assignments have been made for the elastic resonances by R-matrix analysis. Evidence of a positive-parity rotational band has been indicated by the 14C resonances. The proposed level scheme and the strong resonance strength observed in the inelastic channel are in line with the prediction by the antisymmetrized molecular dynamics (AMD) method indicating linear-chain structure in 14C. The results also demonstrate unique and powerful potentials of active-target technology in radioactive-beam experiments and are an important step toward the construction of the full-scale AT-TPC for the ReA3 facility at NSCL.

  18. MicroBooNE Detector Move

    SciTech Connect

    Flemming, Bonnie; Rameika, Gina

    2014-06-25

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  19. MicroBooNE Detector Move

    ScienceCinema

    Flemming, Bonnie; Rameika, Gina

    2014-07-15

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  20. Monitoring Liquid Argon Time Projection Chambers With A Raspberry Pi Camera

    NASA Astrophysics Data System (ADS)

    Patteson, Crystal

    2016-03-01

    The MicroBooNE detector is the first of three liquid argon (LAr) time projection chambers (TPCs) that are central to the short-baseline neutrino program at Fermilab. These chambers consist of thousands of stainless steel or beryllium-copper sense wires that detect ionization electrons produced when neutrinos interact with liquid argon nuclei inside the detector. The wires are several hundred microns in diameter to several meters in length. The construction of such LAr TPCs often takes place in an assembly hall, which is different from the detector hall where the experiment will operate, as was the case with MicroBooNE. Since in situ access to the chamber and its wires in the beamline enclosure can be limited, we investigate the possibility of using a Raspberry Pi single-board computer connected to a low-cost camera installed inside the cryostat as a cost-efficient way to verify the integrity of the wires after transport. We also highlight other benefits of this monitoring device implemented in MicroBooNE, including detector hall surveillance and verification of the status of LED indicators on detector electronics. The author would like to thank Dr. Matthew Toups for his encouragement and guidance on this research project.

  1. First performance results of the ALICE TPC Readout Control Unit 2

    NASA Astrophysics Data System (ADS)

    Zhao, C.; Alme, J.; Alt, T.; Appelshäuser, H.; Bratrud, L.; Castro, A.; Costa, F.; David, E.; Gunji, T.; Kirsch, S.; Kiss, T.; Langøy, R.; Lien, J.; Lippmann, C.; Oskarsson, A.; Rehman, A. Ur; Røed, K.; Röhrich, D.; Sekiguchi, Y.; Stuart, M.; Ullaland, K.; Velure, A.; Yang, S.; Österman, L.

    2016-01-01

    This paper presents the first performance results of the ALICE TPC Readout Control Unit 2 (RCU2). With the upgraded hardware typology and the new readout scheme in FPGA design, the RCU2 is designed to achieve twice the readout speed of the present Readout Control Unit. Design choices such as using the flash-based Microsemi Smartfusion2 FPGA and applying mitigation techniques in interfaces and FPGA design ensure a high degree of radiation tolerance. This paper presents the system level irradiation test results as well as the first commissioning results of the RCU2. Furthermore, it will be concluded with a discussion of the planned updates in firmware.

  2. High-pressure stabilization of argon fluorides.

    PubMed

    Kurzydłowski, Dominik; Zaleski-Ejgierd, Patryk

    2016-01-28

    On account of the rapid development of noble gas chemistry in the past half-century both xenon and krypton compounds can now be isolated in macroscopic quantities. The same does not hold true for the next lighter group 18 element, argon, which forms only isolated molecules stable solely in low temperature matrices or supersonic jet streams. Here we present theoretical investigations into a new high-pressure reaction pathway, which enables synthesis of argon fluorides in bulk and at room temperature. Our hybrid DFT calculations (employing the HSE06 functional) indicate that above 60 GPa ArF2-containing molecular crystals can be obtained by a reaction between argon and molecular fluorine. PMID:26742478

  3. Physics with gamma-beams and charged particle detectors: I) Nuclear structure II) Nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Gai, Moshe

    2015-02-01

    The Charged Particle Working Group (CPWG) is proposing to construct large area Silicon Strip Detector (SSD), a gas Time Projection Chamber detector read by an electronic readout system (eTPC) and a Bubble Chamber (BC) containing superheated high purity water to be used in measurements utilizing intense gamma-ray beams from the newly constructed ELI-NP facility at Magurele, Bucharest in Romania. We intend to use the SSD and eTPC detectors to address essential problems in nuclear structure physics, such as clustering and the many alpha-decay of light nuclei such as 12C and 16O . All three detectors (SSD, eTPC and BC) will be used to address central problems in nuclear astrophysics such as the astrophysical cross section factor of the 12C (α,γ) reaction and other processes central to stellar evolution. The CPWG intends to submit to the ELI-NP facility a Technical Design Report (TDR) for the proposed detectors.

  4. Fourth workshop on experiments and detectors for a relativistic heavy ion collider

    SciTech Connect

    Fatyga, M.; Moskowitz, B.

    1990-01-01

    This report contains papers on the following topics: physics at RHIC; flavor flow from quark-gluon plasma; space-time quark-gluon cascade; jets in relativistic heavy ion collisions; parton distributions in hard nuclear collisions; experimental working groups, two-arm electron/photon spectrometer collaboration; total and elastic pp cross sections; a 4{pi} tracking TPC magnetic spectrometer; hadron spectroscopy; efficiency and background simulations for J/{psi} detection in the RHIC dimuon experiment; the collision regions beam crossing geometries; Monte Carlo simulations of interactions and detectors; proton-nucleus interactions; the physics of strong electromagnetic fields in collisions of relativistic heavy ions; a real time expert system for experimental high energy/nuclear physics; the development of silicon multiplicity detectors; a pad readout detector for CRID/tracking; RHIC TPC R D progress and goals; development of analog memories for RHIC detector front-end electronic systems; calorimeter/absorber optimization for a RHIC dimuon experiment; construction of a highly segmented high resolution TOF system; progress report on a fast, particle-identifying trigger based on ring-imaging and highly integrated electronics for a TPC detector.

  5. Physics with gamma-beams and charged particle detectors: I) Nuclear structure II) Nuclear astrophysics

    SciTech Connect

    Gai, Moshe

    2015-02-24

    The Charged Particle Working Group (CPWG) is proposing to construct large area Silicon Strip Detector (SSD), a gas Time Projection Chamber detector read by an electronic readout system (eTPC) and a Bubble Chamber (BC) containing superheated high purity water to be used in measurements utilizing intense gamma-ray beams from the newly constructed ELI-NP facility at Magurele, Bucharest in Romania. We intend to use the SSD and eTPC detectors to address essential problems in nuclear structure physics, such as clustering and the many alpha-decay of light nuclei such as {sup 12}C and {sup 16}O. All three detectors (SSD, eTPC and BC) will be used to address central problems in nuclear astrophysics such as the astrophysical cross section factor of the {sup 12}C(α,γ) reaction and other processes central to stellar evolution. The CPWG intends to submit to the ELI-NP facility a Technical Design Report (TDR) for the proposed detectors.

  6. Solid-liquid phase transition in argon

    NASA Technical Reports Server (NTRS)

    Tsang, T.; Tang, H. T.

    1978-01-01

    Starting from the Lennard-Jones interatomic potential, a modified cell theory has been used to describe the solid-liquid phase transition in argon. The cell-size variations may be evaluated by a self-consistent condition. With the inclusion of cell-size variations, the transition temperature, the solid and liquid densities, and the liquid-phase radial-distribution functions have been calculated. These ab initio results are in satisfactory agreement with molecular-dynamics calculations as well as experimental data on argon.

  7. A highly accurate interatomic potential for argon

    NASA Astrophysics Data System (ADS)

    Aziz, Ronald A.

    1993-09-01

    A modified potential based on the individually damped model of Douketis, Scoles, Marchetti, Zen, and Thakkar [J. Chem. Phys. 76, 3057 (1982)] is presented which fits, within experimental error, the accurate ultraviolet (UV) vibration-rotation spectrum of argon determined by UV laser absorption spectroscopy by Herman, LaRocque, and Stoicheff [J. Chem. Phys. 89, 4535 (1988)]. Other literature potentials fail to do so. The potential also is shown to predict a large number of other properties and is probably the most accurate characterization of the argon interaction constructed to date.

  8. Noble liquid detectors for fundamental physics and applications

    NASA Astrophysics Data System (ADS)

    Curioni, A.

    2009-12-01

    Noble liquid detectors come in many sizes and configurations and cover a lot of ground as particle and radiation detectors: from calorimeters for colliders to imaging detectors for neutrino physics and proton decay to WIMP Dark Matter detectors. It turns out that noble liquid detectors are a mature technology for imaging and spectroscopy of gamma rays and for neutron detection, a fact that makes them suitable for applications, e.g. cargo scanning and Homeland Security. In this short paper I will focus on liquid xenon and liquid argon, which make excellent detectors for hypothetical WIMP Dark Matter and neutrinos and for much less exotic gamma rays.

  9. Design and Construction of Prototype Dark Matter Detectors

    SciTech Connect

    Peter Fisher

    2012-03-23

    The Lepton Quark Studies (LQS) group is engaged in searching for dark matter using the Dark Matter Time Projection Chamber (DMTPC) at the Waste Isolation Pilot Plant (WIPP) (Carlsbad, NM). DMTPC is a direction-sensitive dark matter detector designed to measure the recoil direction and energy deposited by fluorine nuclei recoiling from the interaction with incident WIMPs. In the past year, the major areas of progress have been: to publish the first dark matter search results from a surface run of the DMTPC prototype detector, to build and install the 10L prototype in the underground laboratory at WIPP which will house the 1 m{sup 3} detector, and to demonstrate charge and PMT readout of the TPC using prototype detectors, which allow triggering and {Delta}z measurement to be used in the 1 m{sup 3} detector under development.

  10. ArgoNeuT: A Liquid Argon Time Projection Chamber Test in the NuMI Beamline

    SciTech Connect

    Soderberg, M.

    2009-10-01

    Liquid Argon Time Projection Chamber detectors are ideally suited for studying neutrino interactions and probing the parameters that characterize neutrino oscillations. The ability to drift ionization particles over long distances in purified argon and to trigger on abundant scintillation light allows for excellent particle identification and triggering capability. In these proceedings the details of the ArgoNeuT test-beam project will be presented after a brief introduction to the detector technique. ArgoNeuT is a 175 liter detector exposed to Fermilab's NuMI neutrino beamline. The first neutrino interactions observed in ArgoNeuT will be presented, along with discussion of the various physics analyses to be performed on this data sample.