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TOTEM is an LHC experiment dedicated to forward hadronic physics. In this contribution, two main parts of its physics programme - proton-proton elastic scattering and total cross-section - are discussed. The analysis procedures are outlined and their status is reviewed.
The Intensity Frontier (IF) experiments at Fermilab require computing, software, data handling, and infrastructure development for detector and beamline design and to extract maximum scientific output from the data. The emphasis of computing at Fermilab for many years has been on the Tevatron collider Run 2 experiments and CMS. Using the knowledge and experience gained from those experiments as well as new computing developments, preparations for computing for IF experiments are ramping up. There are many challenges in IF computing. These include event generators and detector simulation, beamline simulation, detector design and optimization, data acquisition, data handling, data analysis, and all of the associated services required. In this presentation the computing challenges and requirements will be described and the approaches being taken to address them will be shown.
Many experiments whose goal is the search for neutrino-less double beta decay are taking data or in a final construction stage. The need for a tool that allows for an objective comparison between the sensitivity of different experiments is mandatory in order to understand the potential of the next generation projects and focus on the best promising technologies.
We present the prospects for detection of KK-axions using a large volume spherical TPC through natural decay to two gammas. The higher excited mass states of this axion model allows to reach densities which could be detectable by this method. We show the capability of this detector to detect 2-prong events coming from rest-mass axion decays and we provide efficiencies obtained under some gas mixtures and pressure conditions. The sensitivity limit of a future experiment with existing detectors geometry has been estimated for the case of zero background limit.
At first blush, what appears to be a purely physical question to measure any velocity: how to measure the velocity on a one-way trip? However, due to the debates of the clock-synchronization and the successes of Special Relativity (SR), searching of the possibility of one-way speed of light measurement did not receive wider attention since the declaration of the constancy of the speed of light in vacuum by Maxwell's Electrodynamics in 1864. However, our analysis suggests that the debates of the clock synchronization are insignificant when one uses a one-way experiment to test the isotropy of the speed of light - the fundamental postulate of SR. Searching of the possibility of one-way speed of light to test SR is introduced by reviewing recent one-way tests.
We plan to add high precision tracking- and timing-detectors at z = +/- 240 m to CMS to study exclusive processes p + p -- p + X + p at high luminosity. This enables the LHC to be used as a tagged photon-photon collider, with X = l+l- and W+W-, and as a "tagged" gluon-gluon collider (with a spectator gluon) for QCD studies with jets. A second stage at z = 240 m would allow observations of exclusive Higgs boson production.
The Belle-II experiment and superKEKB accelerator will form a next generation B-factory at KEK, capable of running at an instantaneous luminosity 40 times higher than the Belle detector and KEKB. This will allow for the elucidation of many facets of the Standard Model by performing precision measurements of its parameters, and provide sensitivity to many rare decays that are currently inaccessible. This will require major upgrades to both the accelerator and detector subsystems. The imaging Time-of-propagation (iTOP) detector will be a new subdetector of Belle-II that will perform an integral role in Particle identification (PID). It will comprise 16 modules between the tracking detectors and calorimeter; each module consisting of a quartz radiator, approximately 2.5m in length, instrumented with an array of 32 micro-channel plate photodetectors (MCP-PMTs). The passage of charged particles through the quartz will produce a cone of Cherenkov photons that will propagate along the length of the quartz, and be detected by the MCP-PMTs. The excellent spatial, and timing resolution (of 50 picoseconds) of the iTOP system will provide superior particle identification capabilities, particularly allowing for enhanced discrimination between pions and kaons that will be essential for many of the key measurements to performed. The status of the construction of the iTOP subdetector, and performance studies of prototypes at beam tests will be presented, together with prospects for physics measurements that will utilise the PID capabilities of the iTOP system.
Here we present a multichannel system based on superconducting quantum interference devices (SQUIDs) for magnetoencephalography (MEG) measurements, developed and installed at Istituto di Cibernetica (ICIB) in Naples. This MEG system, consists of 163 full integrated SQUID magnetometers, 154 channels and 9 references, and has been designed to meet specifications concerning noise, dynamic range, slew rate and linearity through optimized design. The control electronics is located at room temperature and all the operations are performed inside a Magnetically Shielded Room (MSR). The system exhibits a magnetic white noise level of approximatively 5 fT/Hz1=2. This MEG system will be employed for both clinical and routine use. PACS numbers: 74.81.Fa, 85.25.Hv, 07.20.Mc, 85.25.Dq, 87.19.le, 87.85.Ng
After nearly 80 years since the first guess on its existence, neutrino still escapes our insight: the mass and the true nature (Majorana or Dirac) of this particle is still unknown. In the past ten years, neutrino oscillation experiments have finally provided the incontrovertible evidence that neutrinos mix and have finite masses. These results represent the strongest demonstration that the Standard Model of electroweak interactions is incomplete and that new Physics beyond it must exist. None of these experimental efforts could however shade light on some of the basic features of neutrinos. Indeed, absolute scale and ordering of the masses of the three generations as well as charge conjugation and lepton number conservation properties are still unknown. In this scenario, a unique role is played by the Neutrinoless Double Beta Decay searches: these experiments can probe lepton number conservation, investigate the Dirac/Majorana nature of the neutrinos and their absolute mass scale (hierarchy problem) with unprecedented sensitivity. Today Neutrinoless Double Beta Decay faces a new era where large scale experiments with a sensitivity approaching the so-called degenerate-hierarchy region are nearly ready to start and where the challenge for the next future is the construction of detectors characterized by a tonne-scale size and an incredibly low background, to fully probe the inverted-hierarchy region. A number of new proposed projects took up this challenge. These are based either on large expansions of the present experiments or on new ideas to improve the technical performance and/or reduce the background contributions. n this paper, a review of the most relevant ongoing experiments is given. The most relevant parameters contributing to the experimental sensitivity are discussed and a critical comparison of the future projects is proposed.
This paper introduces a thermal energy harvester turning thermal gradients into electricity by coupling a bimetallic strip to an electret-based converter: the bimetallic strip behaves as a thermal-to-mechanical power converter turning thermal gradients into mechanical oscillations that are finally converted into electricity with the electret. Output powers of 5.4uW were reached on a hot source at 70°C, and, contrary to the previous proofs of concept, the new devices presented in this paper do not require forced convection to work, making them compatible with standard conditions of thermal energy harvesting and environments such as hot pipes, pumps and more generally industrial equipment. Finally, ten energy harvesters have been parallelized and combined to a self-starting power management circuit made of a flyback converter to supply a battery-free Wireless Temperature Sensor Node, sending information every 100 seconds after its startup state.
Detector rate capability is one of the main parameters for designing a new detector for high energy physics due to permanent rise of the beam luminosity of modern accelerators. One of the widely used detectors for particle track reconstruction is a straw detector based on drift tubes. The rate capability of such detectors is limited by the parameters of readout electronics. The traditional method of increasing detector rate capability is increasing their granularity (a number of readout channels) by reducing the straw diameter and/or by dividing the straw anode wire into two parts (for decreasing the rate per readout channel). A new method of designing straw detectors with a high rate capability is presented and tested. The method is based on dividing the straw cathode into parts and independent readout of each part.
Sensors play a key role in detecting both charged particles and photons for all three frontiers in Particle Physics. The signals from an individual sensor that can be used include ionization deposited, phonons created, or light emitted from excitations of the material. The individual sensors are then typically arrayed for detection of individual particles or groups of particles. Mounting of new, ever higher performance experiments, often depend on advances in sensors in a range of performance characteristics. These performance metrics can include position resolution for passing particles, time resolution on particles impacting the sensor, and overall rate capabilities. In addition the feasible detector area and cost frequently provides a limit to what can be built and therefore is often another area where improvements are important. Finally, radiation tolerance is becoming a requirement in a broad array of devices. We present a status report on a broad category of sensors, including challenges for the future and work in progress to solve those challenges
One has investigated possibility of performing NEUTRINO-4 experiment on search for reactor neutrino oscillations into a sterile state at research reactors. The simulated experiment has been conducted at 16 MW reactor WWR-M in PNPI with the purpose of implementing a full scale experiment with the help of 100 MW reactor SM-3 in RIAR. Background conditions for making such an experiment have been examined at both reactors. The conclusion has been made on possible implementation of a full scale experiment NEUTRINO-4 at the reactor SM-3 in RIAR.
Proton radiography is a new scatheless diagnostic tool, and which provides a potential development direction for advanced hydrotesting. Recently a low energy proton radiography system has been developed at CAEP. This system has been designed to use 11MeV proton beam to radiograph thin static objects. This system consists of a proton cyclotron coupled to an imaging beamline. The design features and commissioning results of this radiography system are presented.
Multiple-series and multiple-parallel connections of quantum Hall elementary devices allow the realization of multiple or fractional values of the quantized Hall resistance, rejecting the effect of contact and wiring resistances. We introduce here the multiple-bridge connection, which maintains the properties of multiple-series and parallel connections and allows more freedom in the choice of the topology of networks composed of quantum Hall elements, and the design of more efficient quantum Hall array resistance standards (and other devices). As an example, a 5-element network is analyzed in detail.
In order to measure energy and fluence of neutron fields, with energy ranging from 8 keV to 1 MeV, a new primary standard is being developed at the IRSN (Institute for Radioprotection and Nuclear Safety). This project, micro-TPC (Micro Time Projection Chamber), carried out in collaboration with the LPSC, is based on the nucleus recoil detector principle. The measurement strategy requires track reconstruction of recoiling nuclei down to a few keV, which can be achieved with a low pressure gaseous detector using a micro-pattern gaseous detector. A gas mixture, mainly isobutane, is used as a n-p converter to detect neutrons into the detection volume. Then electrons, coming from the ionization of the gas by the proton recoil, are collected by the pixelised anode (2D projection). A self-triggered electronics is able to perform the anode readout at a 50 MHz frequency in order to give the third dimension of the track. Then the scattering angle is deduced from this track using algorithms. The charge collection leads to the proton energy, taking into account the ionization quenching factor. This article emphasizes the neutron energy measurements of a monoenergetic neutron field produced at 127 keV. The measurements are compared to Monte Carlo simulations using realistic neutron fields and simulations of the detector response. The discrepancy between experiments and simulations is 5 keV mainly due to the calibration uncertainties of 10%.
DAMIC (Dark Matter in CCDs) is a novel dark matter experiment that has unique sensitivity to dark matter particles with masses below 10 GeV. Due to its low electronic readout noise (R.M.S. ~3 e-) this instrument is able to reach a detection threshold below 0.5 keV nuclear recoil energy, making the search for dark matter particles with low masses possible. We report on early results and experience gained from a detector that has been running at SNOLAB from Dec 2012. We also discuss the measured and expected backgrounds and present the plan for future detectors to be installed in 2014.
The Intensity Frontier (IF) is a primary focus of the U.S.-based particle physics program. It encompasses a large spectrum of physics, including quark flavor physics, charged lepton processes, neutrinos, baryon number violation, new light weakly-coupled particles, and nucleons, nuclei and atoms. There are many experiments, a range of scales in data output and throughput, and a wide range in the number of experimenters. The experiments, projects and theory in this area all require demanding computing capabilities and technologies. The IF experiments have significant computing requirements for simulation, theory and modeling, beam line and experiment design, triggers and DAQ, online monitoring, event reconstruction and processing, and physics analysis. We have conducted a qualitative survey of the current and near-term future experiments in the IF to understand the computing demands of this area and their expected evolution. This report details the expected computing requirements for the IF in the context of the Snowmass Community Summer Study 2013.