- [Show abstract] [Hide abstract] ABSTRACT: The Energetic Heavy Ion Sensor (EHIS) is part of the Space Environmental In-Situ Suite (SEISS) for the Geostationary Operational Environment Satellite series R (GOES-R) program. It will measure energetic protons from 10-200 MeV and ions through nickel (Z=28) with similar penetrating power. By use of an Angle Detecting Inclined Sensor (ADIS) system, EHIS achieves single element resolution with extensive on-board event processing. A prototype or "brass-board" instrument, fully functional but not intended for environmental testing, has been completed. In November of 2009, we exposed the prototype to protons at Massachusetts General Hospital (MGH) and in March of 2010, we exposed it to Ni primary and fragment beams at the National Superconducting Cyclotron Laboratory's (NSCL) Coupled Cyclotron Facility (CCF). In both cases, the instrument was rotated over a range of angles and a moving degrader spread the energy from full beam energy to zero energy. We will present results of these tests. These show an angular resolution for the prototype which results in a one sigma charge resolution of ~0.25 e at Ni. The prototype also demonstrated the capability for calculating the charge of 2500 events per second with its internal processor, accumulating those events in on-board charge histograms, and thus providing unprecedented statistics in high flux conditions. The EHIS represents a major advance in capabilities for operational space weather instruments while also providing data quality suitable for scientific research. The EHIS instrument development project was funded by NASA under contract NNG06HX01C.
- [Show abstract] [Hide abstract] ABSTRACT: Measurements of radiation in space, cosmic rays and Solar energetic particles, date back to the dawn of space flight. Solid state detectors, the basis of most modern high energy charged particle instruments, first flew in space in the 1960's. Modern particle spectrometers, such as ACE/CRIS, ACE/SIS and Ulysses/HET, can measure the elemental and isotopic composition of ions through the iron peak. This is achieved by using position sensing detectors (PSD's) arranged into hodoscopes to measure particle trajectories through the instrument, allowing for pathlength corrections to energy loss measurements. The Angle Detecting Inclined Sensor (ADIS) technique measures particle angle of incidence using a simple system of detectors inclined to the instrument axis. It achieves elemental resolution well beyond iron, and isotopic resolution for moderate mass elements without the complexity of position sensing detectors. An ADIS instrument was selected to fly as the High Energy Particle Sensor (HEPS) on NPOESS, but was de-scoped with the rest of the space weather suite. Another ADIS instrument, the Energetic Heavy Ion Sensor (EHIS), is being developed for GOES-R. UNH has built and tested a engineering unit of the EHIS. Applications for manned dosimetery on the Crew Exploration Vehicle (CEV) are also being explored. The basic ADIS technique is explained and accelerator data for heavy ions shown.
- [Show abstract] [Hide abstract] ABSTRACT: The Virtual Energetic Particle Observatory (VEPO) focuses on improved discovery, access, and usability of heliospheric energetic particle and ancillary data products from selected spacecraft and sub-orbital instruments of the heliophysics data environment. The energy range of interest extends over the full range of particle acceleration from keV energies of suprathermal seed particles to GeV energies of galactic cosmic ray particles. Present spatial coverage is for operational and legacy spacecraft operating from the inner to the outer heliosphere, e.g. from measurements by the two Helios spacecraft to 0.3 AU to the inner heliosheath region now being traversed by the two Voyager spacecraft. This coverage will eventually be extended inward to ten solar radii by the planned NASA solar probe mission and at the same time beyond the heliopause into the outer heliosheath by continued Voyager operations. The geospace fleet of spacecraft providing near-Earth interplanetary measurements, selected magnetospheric spacecraft providing direct measurements of penetrating interplanetary energetic particles, and interplanetary cruise measurements from planetary spacecraft missions further extend VEPO resources to the domain of geospace and planetary interactions. Ground-based (e.g., neutron monitor) and high-altitude suborbital measurements can expand coverage to the highest energies of galactic cosmic rays affected by heliospheric interaction and of solar energetic particles. Science applications include investigation of solar flare and coronal mass ejection events, acceleration and transport of interplanetary particles within the inner heliosphere, cosmic ray interactions with planetary surfaces and atmospheres, sources of suprathermal and anomalous cosmic ray ions in the outer heliosphere, and solar cycle modulation of galactic cosmic rays. Robotic and human exploration, and eventual habitation, of planetary and space environments beyond the Earth require knowledge of radiation hazards informed by VEPO data resources. The VEPO project has completed the first year of work to define science requirements, to document and register selected data products in SPASE format while evolving SPASE for increased applicability to VEPO data, and to support enhanced discovery and access for these products through the evolving data query and middleware system of the Virtual Heliospheric Observatory (VHO). The VEPO team operates as a heliophysics focus group for energetic particle data resources in partnership with VHO and also leverages existing data services of NASA's Space Physics Data Facility. We invite comments from the U.S. and international data provider and user communities on review of the current VEPO/VHO user interface, on directions for future evolution of VEPO and supporting data systems including VHO and SPDF, and on relations to other elements of the heliophysics virtual observatory environment.
- [Show abstract] [Hide abstract] ABSTRACT: Ulysses reached its maximum southern heliographic latitude in February, 2007 and is now performing its third fast latitude scan. This scan will cover all latitudes between 79.7° S and 79.7° N at radii between 2.35 and 1.39 AU within 1 year, a time short compared to significant evolution of the solar activity cycle, which is now near its minimum phase. During this solar minimum the solar dipole magnetic field is opposite that observed during the first solar minimum fast latitude scan in 1994-95, a fact which is expected to lead to observable differences in the latitudinal structure of modulated cosmic ray intensities. Measurements of protons, helium, and heavy ions during the recent slow latitude scan, when Ulysses rose from near the ecliptic to maximum southern latitude between 2004 and 2007, a period of declining solar activity, revealed no measurable latitude gradients in HET observations above a threshold (for protons) of about 35 MeV/n. Because of its short duration and restricted radial range, observations during the fast latitude scan provide the best chance for a definitive measure of latitudinal gradients in the cosmic intensity through comparison of Ulysses observations with observations from near-Earth spacecraft, fixed in radius and latitude. However the recent loss of the IMP-8 spacecraft, which had served as a 1 AU baseline for COSPIN HET cosmic ray measurements since the launch of Ulysses, has presented a difficulty for measurement of the small gradients that seem likely given previous observations and the lack of clearly visible latitude effects in the Ulysses cosmic ray data alone. We will present results for heavy ions from the fast latitude scan through the most recent data available, using measurements from Ulysses compared to ACE/CRIS as the 1 AU baseline. For protons and helium, we will present Ulysses observations and evaluate available possible 1 AU baselines, including ERNE data from SOHO, STEREO HET observations, and possible extrapolations from available lower or higher energy measurements which can be used to define the modulation parameter at 1 AU as a function of time, and thus the expected flux variations in Ulysses' energy range at 1 AU. (This work was supported in part by NASA/JPL Contract 1247101)
- [Show abstract] [Hide abstract] ABSTRACT: We report observations of strongly anisotropic flows of electron events originating from Jupiter that were observed during Ulysses distant Jupiter flyby. A scan of the period January 1, 2003 through February 8, 2005 (extending roughly 13 months before and after the closest approach of 0.8AU in early 2004) identified a total of 15 events with significant and short-lived (hours) intensity increases accompanied by strongly anisotropic flows away from Jupiter. We describe the properties of these events, most of which were observed within 1.4AU of Jupiter. We also discuss their implications for large-scale direct magnetic connections across the mean magnetic field and suggest that they may provide evidence for a previously unconsidered way of enhancing propagation of energetic charged particles across the average Parker spiral heliospheric magnetic field, thus increasing the apparent rate of latitudinal and radial cross-field diffusion.
- [Show abstract] [Hide abstract] ABSTRACT: Since the 1970's interplanetary electrons in the MeV energy range, of Jovian origin, have been extensively studied from close to the Sun to beyond the Kronian orbit, near the ecliptic. The Ulysses trajectory allowed to study the propagation of these particles, in a wide range of heliographic latitudes. The location of Jupiter with respect to the structure of the heliospheric magnetic field is precisely determined and non-central. This makes Jovian electrons an ideal opportunity for studying the particle propagation parallel and perpendicular to the heliospheric magnetic field. 12 years after its first encounter in February 1992, the Ulysses mission encountered Jupiter for a second time in February 2004 at a distance of 1684 Jovian radii. The first flyby took place at a distance of closest approach of 6 Jupiter radii (RJ) and changed the inclination of the Ulysses trajectory so that it would pass above the Sun's polar regions. During the 2004 encounter, in contrast to 1992, Ulysses did not enter the Jovian magnetosphere but remained upstream of it. In mid 2002, the MeV electron flux started increasing and displaying large short term variations. These features lasted throughout the encounter, making the electron intensities less obviously correlated with the proximity to Jupiter compared with the first Jovian encounter. In previous studies it has been shown that the diffusion coefficient κ⊥,ϑ perpendicular to the heliospheric magnetic field in polar direction increased in 1998 during the transition from solar minimum to solar maximum close to the ecliptic plane. Although the distant Ulysses encounter took place during the declining phase of the solar cycle the absence of an intensity variation with latitude indicate an unexpected further increase of κ⊥,ϑ. Thus the diffusion coefficients, and in particular perpendicular diffusion in the polar direction, are highly time-dependent. In this paper, we present the corresponding data and discuss the implication for particle propagation in the three-dimensional heliospheric magnetic field.
- [Show abstract] [Hide abstract] ABSTRACT: The measurement of cosmic rays and Solar energetic particles in space is basic to our understanding of the Galaxy, the Sun, phenomena in the Heliosphere and what has come to be known broadly as “space weather”. For these reasons, cosmic ray instruments are common on both scientific spacecraft and operational spacecraft such as weather satellites.The resource constraints on spacecraft generally mean that instruments that measure cosmic rays and Solar energetic particles must have low mass (a few kg) and low power (a few W), be robust and reliable yet still highly capable. Such instruments must identify ionic species (at least by element, preferably by isotope) from protons through the iron group. The charge and mass resolution of heavy ion instruments in space depends upon determining ions’ angles of incidence. The Angle Detecting Inclined Sensor (ADIS) system is a highly innovative and uniquely simple detector configuration used to determine the angle of incidence of heavy ions in space instruments. ADIS replaces complex position sensing detectors (PSDs) with a system of simple, reliable and robust Si detectors inclined at an angle to the instrument axis.In August 2004, we tested ADIS prototypes with a 48Ca beam at the National Superconducting Cyclotron Laboratory's (NSCL) Coupled Cyclotron Facility (CCF). Among the analyses performed on the data taken at the NSCL, we demonstrate that our prototype design with an ADIS system has a charge resolution of less than 0.25e. We also present a more generalized analytic derivation of instrument response and report on the corresponding analysis of Monte-Carlo modeling data.
- [Show abstract] [Hide abstract] ABSTRACT: The High-Energy Telescope with neutron detection capabilities (HETn) for the Solar Orbiter will measure and resolve energetic charged particles, in particular electrons, proton, and heavy ions up to Fe including selected isotopes up to energies equivalen to the penetration depth of 100 MeV protons. The full active anti-coincidence encloses detectors sensitive to 1-30 MeV neutrons and 0.5-5 MeV X-/gamma-rays. The sensor consists of the angle-detecting inclined sensors (ADIS) solid-state detector detector telescope utilizing a shared calorimeter for total energy and X-/gamma-ray measurement. A separate plastic detector provides sensitivity to neutrons via the recoil process. HETn will open a new window on solar eruptive events with its neutron detection capability and allows determination of high-energy close to the Sun. Timing and spectral information on neutral particles (neutrons and X-/gamma rays ), on relativistic electrons and high-energy heavy ions will provide new insights into the processes which accelerate particles to high energies at the sun and into transport processes between the source and the spacecraft in the near-Sun environment.
- [Show abstract] [Hide abstract] ABSTRACT: The Virtual Cosmic Ray Observatory (ViCRO) is proposed to extend planned capabilities of existing or developing heliophysics virtual observatories with a collection of important cosmic ray datasets with focus on interplanetary solar & heliospheric science applications and on planetary interac-tions. Core operational data sources include cosmic ray instrumentation on the Heliospheric Network (HN) spacecraft, ephemeris data services for these sources and solar system objects, and supporting data on high energy cosmic rays from ground-based neutron monitor and high-altitude balloon instruments. ViCRO would initially support data query, access, and other VxO functions through a common middle-ware interface already in development for the Virtual Heliospheric Observatory.
- [Show abstract] [Hide abstract] ABSTRACT: The heliosphere is pervaded by interplanetary energetic particles, traditionally also called cosmic rays, from solar, internal heliospheric, and galactic sources. The particles species of interest to heliophysics extend from plasma energies to the GeV energies of galactic cosmic rays still measurably affected by heliospheric modulation and the still higher energies contributing to atmospheric ionization. The NASA and international Heliospheric Network of operational and legacy spacecraft measures interplanetary fluxes of these particles. Spatial coverage extends from the inner heliosphere and geospace to the heliosheath boundary region now being traversed by Voyager 1 and soon by Voyager 2. Science objectives include investigation of solar flare and coronal mass ejection events, acceleration and transport of interplanetary particles within the inner heliosphere, cosmic ray interactions with planetary surfaces and atmospheres, sources of suprathermal and anomalous cosmic ray ions in the outer heliosphere, and solar cycle modulation of galactic cosmic rays. The Virtual Energetic Particle Observatory (VEPO) will improve access and usability of selected spacecraft and sub-orbital NASA heliospheric energetic particle data sets as a newly approved effort within the evolving heliophysics virtual observatory environment. In this presentation, we will describe current VEPO science requirements, our initial priorities and an overview of our strategy to implement VEPO rapidly and at minimal cost by working within the high-level framework of the Virtual Heliospheric Observatory (VHO). VEPO will also leverage existing data services of NASA's Space Physics Data Facility and other existing capabilities of the U.S. and international heliospheric research communities.
- [Show abstract] [Hide abstract] ABSTRACT: Cosmic ray modulation models that include gradient and curvature drifts predict that, for the present sign of the heliospheric magnetic field, the modulated cosmic ray intensity should decrease from the equator towards the poles near solar minimum, corresponding to negative latitude gradients. In the previous high latitude phases of the Ulysses mission near solar minimum in 1994-95, positive latitude gradients were found, consistent with predictions for the sign of the heliospheric field observed at that time. Also, quasi-periodic intensity modulations produced by CIRs in the current sheet were observed to persist to near-polar latitudes. Since its aphelion and distant Jupiter flyby near the heliospheric equator in 2004 Ulysses has been climbing steadily in latitude. Ulysses remained in the region swept by the heliospheric current sheet through 2005. It exited the current sheet region in early 2006 at a latitude of about 38° S. By July 2006 it had reached a latitude of >50° S, well above the current sheet. In the same period, solar activity has steadily decreased, though a few large solar energetic particle/CME events continued to occur through 2005. Since early 2006, no significant solar events have disrupted measurement of modulated cosmic ray intensities, which continue rising towards solar minimum levels. With measurements of >35 MeV/n protons and helium from the COSPIN High Energy Telescope on Ulysses compared to observations in nearly identical energy ranges from the IMP-8 CRNC experiment near Earth, we have been attempting to measure the magnitude and sign of latitude gradients as Ulysses rises in latitude. In the current sheet region, we find no evidence for latitude gradients in either protons or helium, and we find much smaller intensity variations in response to CIRs than observed in the similar phase of the previous solar cycle. We will report continuing observations to latitudes >50° S relating to our search for latitude gradients and also for evidence of the persistence of intensity modulations produced by CIRs to high latitudes. This work was supported in part by NASA/JPL Contract 1247101.
- [Show abstract] [Hide abstract] ABSTRACT: Probing the dynamics of energetic solar phenomena at small heliocentric distances can be conducted with the Solar Orbiter spacecraft. The flux and energy distribution of low-energy neutrons that arise in flares from nuclear reactions is of particular interest. Solar neutrons below 30 MeV suffer significant decay losses before reaching 1 AU. At heliocentric radii as close as 0.3 AU the number of surviving neutrons from a solar event is dramatically greater. Measurements of neutrons in the energy range 1-10 MeV provide a new indicator of heavy ion interactions at low energies, where the majority of particles reside. An instrument to make these measurements must be compact, lightweight, and efficient. We discuss an instrument concept for making these measurements, including use of neutron imaging techniques to increase the sensitivity and to optimize the signal-to-noise ratio.
- [Show abstract] [Hide abstract] ABSTRACT: We describe a phoswich-based detector concept for studies of low energy (∼1–10 MeV) solar neutrons in the innermost heliosphere (R <∼ 0.5 AU). The detector has applications both as a very low mass (<∼1 kg), low power (∼1–2 W) stand-alone instrument, and as a component to enhance the capabilities of more sophisticated instruments, for example, the fast neutron imaging telescope instrument described by Moser et al. [Moser, M.R., Flückiger, E.O., Ryan, J.M., et al. A fast neutron imaging telescope for inner heliosphere missions. Adv. Space Res., in press, this issue, doi:10.1016/j.asr.2005.03.037]. In its most basic form, the detector consists of a small volume (∼1 cm3) of fast organic scintillator completely surrounded by a slow inorganic scintillator. The dimensions of the organic scintillator are chosen to minimize multiple n–p scatterings while retaining adequate sensitivity. The inorganic scintillator provides anti-coincidence protection against energetic charged particles. A single PM tube views light from both scintillators. Pulse shape analysis identifies as potential neutrons those events where only the organic scintillator contributes to the signal. The signal size corresponds to the energy of the recoil proton from an n–p elastic scatter, on average half the energy of the incident neutron. An instrument based on this concept would provide measurements of the neutron flux and, through statistical analysis of recoil proton energies, basic information about the neutron spectrum.
- [Show abstract] [Hide abstract] ABSTRACT: For about the last 40 years, we have been trying to understand the propagation of cosmic rays and other energetic charged particles through the interplanetary medium. Identification of the basic processes affecting the propagation, namely diffusion, convection by the solar wind, adiabatic deceleration, and gradient and curvature drifts, was attained early on, but reaching detailed physical understanding, particularly of the roles of diffusion and gradient and curvature drifts, continues as an active topic of research to this day. Particularly unclear is the nature of the cross-field propagation. Many observations seem to require more efficient cross-field propagation than theoretical propagation models can easily produce. At the same time, there are other observations that seem to show strong guidance of the particles by the interplanetary magnetic field. With current measurements from spacecraft near Earth and from the Ulysses spacecraft, which samples nearly the complete range of heliographic latitudes in the inner heliosphere, critical tests of the ways in which cosmic rays and other energetic charged particles propagate through the interplanetary medium are possible. I briefly review the status of observations that are relevant to the characterization of diffusive propagation in the inner heliosphere and will present evidence for a possibly previously overlooked contribution from transport along magnetic flux tubes that deviate dramatically from the average interplanetary spiral configuration.
- [Show abstract] [Hide abstract] ABSTRACT: We report comprehensive observations of solar energetic particle intensities at energies from 0.3 to >100 MeV made by the suite of six Ulysses COSPIN energetic charged particle instruments on the Ulysses spacecraft during the period of intense solar activity in October/November 2003. We also discuss observations of particle anisotropies in selected energy ranges made by these instruments. Located near the orbit of Jupiter and only about 6° north of the heliographic equatorial plane, Ulysses provided important measurements for comparison with 1 AU observations and for assessing the nature of particle propagation in this period of isolated but intense solar activity in the declining phase of the solar activity cycle. The most significant conclusion is that the particle populations in the inner heliosphere were highly nonuniform throughout the events, strongly guided and confined by magnetic structures such as stream interfaces in the solar wind. This provides strong contrast to the nearly uniform intensities that were quickly established after large events near the peak of the solar cycle. Points of particular interest are (1) possible observation at 5.2 AU during onset of differential filling of flux tubes and confinement of high-energy (>∼20 MeV) particles to flux tubes in the course of propagation from the source; (2) apparent exclusion of energetic particles from the interior of a large coronal mass ejection (CME); (3) possible triggered release of electrons from Jupiter by interaction with the same CME, and propagation of the electrons within the closed fields of the CME.
- [Show abstract] [Hide abstract] ABSTRACT: Since launch in Oct. 1990 Ulysses sampled the Heliosphere between Earth and Jupiter in three dimensions continuously. With varying heliomagnetic distance to Jupiter and changing solar activity the Jovian electron population varied considerably during this time. In 1992 and 2004 Ulysses had two encounters with Jupiter allowing to study the propagation of Jovian electrons originating from an off-centre point source in the heliosphere. (These observations are crucial for evaluating and testing propagation models.) The closest approach to Jupiter was 0.003 AU in 1992 and 0.803 AU in 2004 (6 RJ and 1682 RJ respectively). In addition Jovian electron jets were observed in during both encounters in the 3-10 MeV range as events with sharp increase and decrease, strong anisotropy, and durations of up to a few hours. While the global observations have been discussed in Heber et al. (2005), the Jovian jet measurements made by the COSPIN KET as far out as 2.2 AU from the planet after the distant encounter in 2004 will be presented in this paper. A report of COSPIN HET measurements of jets has been given by McKibben et al. (2005).
- [Show abstract] [Hide abstract] ABSTRACT: In this paper, we present the final report of the data obtained from the Space Dust (SPADUS) instrument on the Earth-orbiting Advanced Research and Global Observation Satellite (ARGOS). The University of Chicago's SPADUS instrument on the US Air Force's Advanced Research and Global Observation Satellite has been operating in a nearly polar orbit, at an altitude of approximately 850 km, since soon after its launch on day 54, 1999 (23 February) until termination of the SPADUS operations on day 248, 2001 (5 September).The instrument consists of a polyvinylidene fluoride (PVDF) dust trajectory system, which includes two planar arrays of PVDF sensors (a total of 16 sensors per array) separated by 20.25 cm to provide time of flight (TOF) measurements. The trajectory system measures dust particle flux, mass distribution, velocity and trajectory. The instrument also includes the SPADUS Ancillary Diagnostic Sensor (ADS) subsystem, which measured energetic charged particles (electrons, protons, etc).The PVDF dust trajectory system detected a total of 368 dust impacts over the SPADUS live-time interval of 739 days, yielding an average particle flux of 0.50 impacts/day. Of these 368 impacts, 35 were D1–D2 type events—where particles impacted and penetrated a D1 sensor, then impacted a D2 rear array sensor—allowing for time-of-flight measurements. Of the 35 D1–D2 impacts on SPADUS, we identified 19 D1–D2 impacts yielding TOF values. Of these 19 events, 14 were ambiguous (either bound or interplanetary) and 5 were unambiguous interplanetary impacts. Examples of particle orbits for debris particles as well as D1–D2 impacts are detailed. We also describe transient particle streams detected by the SPADUS trajectory system, resulting from the passage of ARGOS through streams of debris particles in Earth orbit. One of the streams was shown to result from detection by SPADUS of the debris generated by the explosion of a Chinese booster rocket.The SPADUS flight data accumulated over the 30-month mission shows that PVDF-based dust instruments utilizing two planar arrays of PVDF dust sensors in a TOF arrangement—can provide useful measurements of particle velocity, mass distribution, flux, trajectory and particle orbital elements.
- [Show abstract] [Hide abstract] ABSTRACT: The High Energy Particle Sensor (HEPS), an instrument in the Space Environment Sensor Suite (SESS) on the National Polar-orbiting Operational Environmental Satellite System (NPOESS), will measure protons and He from 10 MeV/n to > 300 MeV/u and heavier ions through Ni at corresponding energies with a geometrical factor of ~1 cm2 ster. It will thus provide useful data on Solar Energetic Particles (SEP), Galactic Cosmic Rays (GCR) and Anomalous Cosmic Rays (ACR). In particular, HEPS is designed so as not to saturate at the highest fluxes of SEPs thus far observed. With the NPOESS polar orbit, HEPS can use the geomagnetic field to study the charge states of the different particle populations, as previously demonstrated on the SAMPEX mission. For example, GRCs are fully stripped, ACRs are mainly singly charged while SEPs are partially stripped. The charge state of SEPs is a diagnostic of the ion source population. HEPS will be based on the Angle Detecting Inclined Sensors (ADIS) system. A prioritized sample of events will be pulse-height analyzed and processed on-board. Owing to the simplicity of the ADIS analysis, events will be identified by charge and binned on-board by the HEPS central processor unit for telemetry to the ground. HEPS will have single element resolution with sigma < 0.25 e.
- [Show abstract] [Hide abstract] ABSTRACT: We report here the first results from a working ADIS-type charged particle detector for use in space missions. The ADIS system consists of three detectors, two of which are inclined at an angle to the telescope axis, forming the first detectors in a multi-element charged particle instrument. By comparing signals from the ADIS detectors, the angle of incidence of incoming particles can be determined. The ADIS system can thus replace hodoscopes using conventional position sensing detectors (PSD's). PSD's add significant complexity and require additional electronics, increasing instrument mass, power usage and, in many cases telemetry requirements. The ADIS system's angle determination requires only the processing of simple equations, easily within the capabilities of even the slowest on-board processors. Thus a light-weight, low-power ADIS based charged particle telescope is a good candidate for studying high energy charged particles in deep space. We have built a prototype ADIS telescope for laboratory testing. While the detector housing is made specifically for this system, this test model used off-the-shelf components. The prototype model was taken to the National Superconducting Cyclotron Laboratory at Michigan State University. There the instrument was subjected to a primary beam of 48Ca, and fragment beams from that primary. Various detector systems are compared to show how the instrument response varies with respect to detector thickness and orientation. The preliminary results show that the ADIS instrument can distinguish element in the sub-Ca region with charge resolution of ~0.25e.
University of Chicago
Chicago, Illinois, United States
- Enrico Fermi Institute
University of Illinois at ChicagoChicago, Illinois, United States