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In this paper we discuss results relevant to 3D Double-Side Double Type Column (3D-DDTC) pixel sensors fabricated at FBK (Trento, Italy) and oriented to the ATLAS upgrade.
In this paper we report the development of the design verification model (DVM) of Rb atomic frequency standard. The Rb atomic frequency standard or clock has two distinct parts. One is the Physics Package where the hyperfine transitions produce the clock signal in the integrated filter cell configuration and the other is the electronic circuits which generate the resonant microwave hyperfine frequency, phase modulator and phase sensitive detector. In this paper the details of the Rb Physics package and the electronic circuits are given. The effect of putting the photo detector inside the microwave cavity is studied and reported with its effect on the resonance signal profile. The Rb clock frequency stability measurements have also been discussed.
A basic prototype for an analog hadron calorimeter for a future linear collider detector is currently being realized by the CALICE collaboration. The aim is to show the feasibility to build a realistic detector with fully integrated readout electronics. An important aspect of the design is the improvement of the jet energy resolution by measuring details of the shower development with a highly granular device and combining them with the information from the tracking detectors. Therefore, the signals are sampled by small scintillating tiles that are read out by silicon photomultipliers. The ASICs are integrated into the calorimeter layers and are developed for minimal power dissipation. An embedded LED system per channel is used for calibration. The prototype has been tested extensively and the concept as well as results from the DESY test setups are reported here.
The ever increasing need for product advancement and miniaturization keeps thin film assemblies, membranes, magnetic and non-magnetic multilayer and patterned heterostructures in the limelight of material science and technological development. A number of thin film and surface characterization methods have emerged recently to meet the new challenges. The increased interest in magnetic thin film analytical instruments - mainly triggered by the discovery of the giant magnetoresistance and related phenomena1 - resulted in a boom of PNR studies as well as of the construction of a number of new neutron reflectometers with polarization option at neutron sources all over the world. Here we report on the design, construction and operation parameters and first example uses of the "Grazing Incidence Neutron Apparatus" (GINA) a recently installed neutron reflectometer at the Budapest Neutron Centre (BNC), Hungary.
Optical interconnects are foreseen as a potential solution to improve the performance of data transmission in high speed integrated circuits since electrical interconnects operating at high bit rates have several limitations which creates a bottleneck at the interconnect level. The objective of the work is to model and then simulate the MQWM based optical interconnect transmitter. The power output of the simulated modulator is then optimized with respect to various parameters namely contrast ratio, insertion loss and bias current. The methodology presented here is suitable for investigation of both analog and digital modulation performance but it primarily deals with digital modulation. We have not included the effect of carrier charge density in multiple quantum well simulation.
NO$ν$A is an accelerator-based neutrino oscillation experiment which has a great potential to measure the last unknown mixing angle $θ_{13}$, the neutrino mass hierarchy, and the CP-violation phase in lepton sector with 1) 700 kW beam, 2) 14 mrad off the beam axis, 3) 810 km long baseline. The Near Detector on the Surface is fully functioning and taking both NuMI and Booster beam data. The far detector building achieved beneficial occupancy on April 13. This proceeding will focus on the DAQ software system.
Space provides unique opportunities to test gravitation. By using an interplanetary spacecraft as a test mass, it is possible to test General Relativity at the Solar System distance scale. This requires to compute accurately the trajectory of the spacecraft, a process which relies on radio tracking and is limited by the uncertainty on the spacecraft non-gravitational acceleration. The Gravity Advanced Package (GAP) is designed to measure the non-gravitational acceleration without bias. It is composed of an electrostatic accelerometer supplemented by a rotating stage. This article presents the instrument and its performances, and describes the method to make unbiased measurements. Finally, it addresses briefly the improvement brought by the instrument as far as orbit reconstruction is concerned.
The MicroBooNE experiment is an upcoming liquid argon TPC experiment which will pursue a program of short baseline neutrino physics in the Fermilab Booster Neutrino Beam, starting in early 2014. I give a description of the experiment and review the current status of various aspects of the MicroBooNE detector.
We present the results of the characterization of novel n-in-p planar pixel detectors, designed for the future upgrades of the ATLAS pixel system. N-in-p silicon devices are a promising candidate to replace the n-in-n sensors thanks to their radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed with the ATLAS pixel read-out systems, TurboDAQ and USBPIX, before and after irradiation with 25 MeV protons and neutrons up to a fluence of 5x10**15 neq /cm2. The charge collection measurements carried out with radioactive sources have proven the feasibility of employing this kind of detectors up to these particle fluences. The collected charge has been measured to be for any fluence in excess of twice the value of the FE-I3 threshold, tuned to 3200 e. The first results from beam test data with 120 GeV pions at the CERN-SPS are also presented, demonstrating a high tracking efficiency before irradiation and a high collected charge for a device irradiated at 10**15 neq /cm2. This work has been performed within the framework of the RD50 Collaboration.
The Pixel Detector (PXD) of the Belle II experiment at superKEKB accelerator in Japan is based in the DEPFET technology. Two layers of 8+12 modules at a radius of 13 and 22 mm will give a spatial resolution below 10 mm. The radiation level expected in the first layer in ten years of operation is about 10 MRad of total ionizing dose. In order to study the tolerance of the DEPFET technology sixty devices were irradiated using a standard procedure like 60Co gamma source. Different doping types, channel sizes and biasing conditions were studied
The Karlsruhe Tritium Neutrino experiment KATRIN will allow a model independent measurement of the neutrino mass scale with an expected sensitivity of 0.2 eV/c^{2} (90% C.L.) and so will help to clarify the role of neutrinos in the early universe is the direct measurement of the mass of the electron anti-neutrino. KATRIN investigates spectroscopically the electron spectrum from tritium beta- decay close to the kinematic endpoint of 18.6 keV with a high resolution electro-static filter of unprecedented energy resolution of 0.93 eV. KATRIN will be built at the Tritium Laboratory Karlsruhe on site of the KIT Campus North. For such a precise mass-determination a key parameter is the stability of the source in terms of beta-activity und isotopic purity. For that purpose KATRIN uses a strong windowless gaseous tritium source of almost pure molecular tritium (95%) with a throughput of 40 g tritium per day stabilized on 0.1% level. The decay electrons are guided adiabatically from the source to the spectrometer by means of superconducting magnets while at the same time the tritium flow rate to the spectrometers has to be reduced by a factor > 1E14. To reach the sensitivity KATRIN is aiming for, an high energy resolution as well as high statistics and low background are needed. A tandem spectrometer system is used for energy analysis. The transport section consists of a differential pumping system (DPS2-F) and a cryogenic pumping section (CPS). In the DPS2-F the tritium flow will be reduced by differential pumping while in the CPS tritium will be adsorbed on a pre-condensed argon layer prepared inside KATRIN's beamtube. To assure the required stability of the source on 0.1% level a stabilized tritium injection in the source is required. This is done by closed tritium loops. The purity and composition of the injected gas will be monitored by Laser Raman spectroscopy.
Gas Electron Multipliers (GEM) are an interesting technology under consideration for the future upgrade of the forward region of the CMS muon system, specifically in the $1.6<| η|<2.4$ endcap region. With a sufficiently fine segmentation GEMs can provide precision tracking as well as fast trigger information. The main objective is to contribute to the improvement of the CMS muon trigger. The construction of large-area GEM detectors is challenging both from the technological and production aspects. In view of the CMS upgrade we have designed and built the largest full-size Triple-GEM muon detector, which is able to meet the stringent requirements given the hostile environment at the high-luminosity LHC. Measurements were performed during several test beam campaigns at the CERN SPS in 2010 and 2011. The main issues under study are efficiency, spatial resolution and timing performance with different inter-electrode gap configurations and gas mixtures. In this paper results of the performance of the prototypes at the beam tests will be discussed.
We have developed a cryogenic platform for the control and readout of spin qubits that comprises a high density of dc and radio frequency sample interconnects based on a set of coupled printed circuit boards. The modular setup incorporates 24 filtered dc lines, 14 control and readout lines with bandwidth from dc to above 6 GHz, and 2 microwave connections for excitation to 40 GHz. We report the performance of this platform, including signal integrity and crosstalk measurements and discuss design criteria for constructing sample interconnect technology needed for multi-qubit devices.
We report on the screening of samples of titanium metal for their radio-purity. The screening process described in this work led to the selection of materials used in the construction of the cryostats for the Large Underground Xenon (LUX) dark matter experiment. Our measurements establish titanium as a highly desirable material for low background experiments searching for rare events. The sample with the lowest total long-lived activity was measured to contain <0.25 mBq/kg of U-238, <0.2 mBq/kg of Th-232, and <1.2 mBq/kg of K-40. Measurements of several samples also indicated the presence of short-lived (84 day half life) Sc-46, likely produced cosmogenically via muon initiated (n,p) reactions.
The proposed introduction of a soluble gadolinium (Gd) compound into water Cherenkov detectors can result in a high efficiency for the detection of free neutrons capturing on the Gd. The delayed 8 MeV gamma cascades produced by these captures, in coincidence with a prompt positron signal, serve to uniquely identify electron antineutrinos interacting via inverse beta decay. Such coincidence detection can reduce backgrounds, allowing a large Gd-enhanced water Cherenkov detector to make the first observation of supernova relic neutrinos and high precision measurements of Japan's reactor antineutrino flux, while still allowing for all current physics studies to be continued. Now, a dedicated Gd test facility is operating in the Kamioka Mine. This new facility houses everything needed to successfully operate a Gd doped water Cherenkov detector. Successful running of this facility will demonstrate that adding Gd salt to SK is both safe for the detector and is capable of delivering the expected physics benefits.
A new method for highly selective remote sensing of atmospheric trace polar molecular gases is described. Based on infrared/terahertz double resonance spectroscopic techniques, the molecule- specific coincidence between the lines of a CO2 laser and rotational-vibrational molecular absorption transitions provide two dimensions of recognition specificity: infrared coincidence frequency and the corresponding terahertz frequency whose absorption strength is modulated by the laser. Atmospheric pressure broadening expands the molecular recognition "specificity matrix" by simultaneously relaxing the infrared coincidence requirement and strengthening the corresponding terahertz signature. Representative double resonance spectra are calculated for prototypical molecules CH3F and CH3Cl and their principal isotopomers, from which a heuristic model is developed to estimate the specificity matrix and double resonance signature strength for any polar molecule.
We report an automated characterization of a single-photon detector based on commercial silicon avalanche photodiode (PerkinElmer C30902SH). The photodiode is characterized by I-V curves at different illumination levels (darkness, 10 pW and 10 uW), dark count rate and photon detection efficiency at different bias voltages. The automated characterization routine is implemented in C++ running on a Linux computer.
We propose a revolutionary way of studying the sur-face of Mars using a wind-driven network of mobile sensors- Gone with the Wind ON_Mars (GOWON). GOWON is envisioned to be a scalable, 100% self energy-generating and distributed system that allows in-situ mapping of a wide range of phenomena in a much larger portion of the surface of Mars compared to earlier missions. It could radically improve the possibility of finding rare phenomena like bio signatures through random wind-driven search. It could explore difficult terrains that were beyond the reach of previous missions, such as regions with very steep slopes, cluttered surfaces and/or sand dunes; GOWON is envisioned as an on going mission with a long life span. It could achieve any of NASA's scientific objectives on Mars in a cost-effective way, leaving a long lasting sensing and searching infrastructure on Mars. GOWON is a 2012 Step B invitee for NASA Innovative Advanced Concept (NIAC). It addresses the challenge area of the Mars Surface System Capabilities area. We believe the challenge to be near-term, i.e., 2018-2024.