A powerful new electron-ion collider (EIC) has been recommended in the 2015 Long Range Plan for Nuclear Science for probing the partonic structure inside nucleons and nuclei with unprecedented ...precision and versatility 1. EIC detectors are currently under development 2, all of which require hadron identification over a broad kinematic range. A prototype ring imaging Cherenkov detector has been developed for hadron identification in the momentum range from 3 GeV/c to 10 GeV/c. The key feature of this new detector is a compact and modular design, achieved by using aerogel as radiator and a Fresnel lens for ring focusing. In this paper, the results from a beam test of a prototype device at Fermilab are reported.
Design and R&D of RICH detectors for EIC experiments Del Dotto, A.; Wong, C. -P.; Allison, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2017, Letnik:
876, Številka:
C
Journal Article
Recenzirano
An Electron-Ion Collider (EIC) has been proposed to further explore the strong force and QCD, focusing on the structure and the interaction of gluon-dominated matter. A generic detector R& D program ...(EIC PID consortium) for the particle identification in EIC experiments was formed to explore technologically advanced solutions in this scope. In this context two Ring Imaging Cherenkov (RICH) counters have been proposed: a modular RICH detector which consists of an aerogel radiator, a Fresnel lens, a mirrored box, and pixelated photon sensor; a dual-radiator RICH, consisting of an aerogel radiator and C2F6 gas in a mirror-focused configuration. We present the simulations of the two detectors and their estimated performance.
Neutron spin rotation is expected from quark-quark weak interactions in the standard model, which induce weak interactions among nucleons that violate parity. We present the results from an ...experiment searching for the effect of parity violation via the spin rotation of polarized neutrons in a liquid
He medium. The value for the neutron spin rotation angle per unit length in
He,
rad/m, is consistent with zero. The result agrees with the best current theoretical estimates of the size of nucleon-nucleon weak amplitudes from other experiments and with the expectations from recent theoretical approaches to weak nucleon-nucleon interactions. In this paper we review the theoretical status of parity violation in the
He system and discuss details of the data analysis leading to the quoted result. Analysis tools are presented that quantify systematic uncertainties in this measurement and that are expected to be essential for future measurements.
This article examined the effect of Modern Standard Arabic orthography on speech production quality (syllable stress and vowels) by 23 Arabic-speaking children with severe or profound hearing loss ...aged 8-12 years. Children produced 15 one-syllable minimal pairs of words that differed in vowel length (short vs. long) and 20 two-syllable minimal pairs differing in stress pattern. Each word was produced in three tasks: reading partially or fully vowelized words and imitation of aural stimuli. Results showed that fully vowelized words ensured vowel production: high-quality productions appeared on 99%, 74%, and 59% of productions on reading fully vowelized words, partially vowelized words, and on imitation, respectively. Moreover, correct vowel production affected correct consonant production. Correct production of stress was best on reading fully vowelized words, appearing on 54%, 21%, and 33% of productions for fully vowelized words, partially vowelized words, or imitation, respectively. Findings suggest the need to present fully vowelized written texts when teaching speech production to children with hearing loss. Such presentations enable more accurate productions that result in more intelligible speech.
A pioneering experiment in {lambda} hypernuclear spectroscopy, undertaken at the Thomas Jefferson National Accelerator Facility (J Lab), was recently reported. The experiment used the high precision, ...continuous electron beam at JLab, and a special arrangement of spectrometer magnets to measure the hypernuclear spectrum from C and {sup 7}Li targets using the (e,e'K{sup +}) reaction. The {sub {lambda}}{sup 12}B spectrum found in this investigation was previously published, but is reported here in more detail, with improved resolution. In addition, the results of a {sub {lambda}}{sup 7}He spectrum also obtained in the experiment, are shown. This latter spectrum indicates the need for a more detailed few-body calculation of the hypernucleus and the reaction process. The success of the experiment demonstrates the potential of the (e,e'K{sup +}) reaction for high resolution spectroscopy of hypernuclear spectra.
Large Area Picosecond Photon Detectors (LAPPDs) are micro-channel plate based photosensors featuring hundreds of square centimeters of sensitive area in a single package and capable of providing ...timing resolution on the order of 50 ps for single photon detection. However, LAPPDs currently do not exist in finely pixelated 2D readout configurations which, in addition to high-resolution timing, would also provide high spatial resolution required for Ring Imaging CHerenkov (RICH) detectors. One of the recent LAPPD models (Gen II) provides the opportunity to overcome the lack of pixellation by coupling an external readout to the sealed detector itself. The readout plane in this case is a simple printed circuit board (PCB) that can be laid out in a custom application-specific way for 1D or 2D sensitive area pixellation. This allows for a much shorter readout-plane prototyping cycle and provides unprecedented flexibility in choosing an appropriate segmentation that can be optimized for any particular detector need in terms of pad size, orientation, and shape. We fully exploit this feature by designing and testing a variety of readout PCBs with conventional square pads and interleaved anode designs. Data acquired in the lab using a laser system to probe the response of several interleaved and standard pixelated patterns are presented as well as results from a beam test.
J.Phys.Conf.Ser.69:012033,2007 The STAR experiment uses polarized p+p collisions at RHIC to determine the
contributions to the spin of the proton from gluon spin and from orbital
angular momentum of ...the quarks and gluons. Selective STAR measurements of the
longitudinal double spin asymmetry for inclusive jet and inclusive hadron
production are presented here. In addition, we report measurements of the
transverse spin asymmetry for di-jet production at mid-rapidity and the
transverse single-spin asymmetry for forward pi0 production
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