urn:esa:psa:context:instrument:uly.epac 1.0 1.11.0.0 Product_Context urn:nasa:pds:context:instrument:epac.uly 2021-02-24 1.0 Changed inst LIDs from u:n:p:c:i:instID.scID to u:n:p:c:i:scID.instID Changed LIDs from urn:nasa:pds: to urn:esa:psa: And per "Guide toPDS4 Context Products" v1.7, changed all lidvid_reference to lid_reference urn:esa:psa:context:instrument_host:spacecraft.uly instrument_to_instrument_host Keppler, E., ULYSSES, eine Raumsonde, die uber die Pole der Sonne fliegt. Z. Flugwiss. Weltraumforsch., 16, 133-142, 1992. reference.KEPPLER1992 Keppler, E., B. Blake , A. Korth, Olsen S., J. Quenby, A. Richter, Umlauft G., The energetic particle composition (EPAC) experiment on the International Solar Polar Mission (ISPM ESA- Spacecraft), MPAE-W-78-80-39, 1980. reference.KEPPLERETAL1980 Keppler, E., M. Andre, J.B. Blake, A. Korth, J. Quenby, G. Umlauft, and J. Woch, The ULYSSES energetic particle composition experiment EPAC., MPAE-W-78-91-16, July, 1991. reference.KEPPLERETAL1991 Keppler, E., J.B. Blake, D. Hovestadt, A. Korth, J.J. Quenby, G. Umlauft, and J. Woch, The ULYSSES energetic particle composition experiment EPAC., Astron. & Astrophys., Suppl. Ser., 92, 317-331, 1992. reference.KEPPLERETAL1992A ENERGETIC PARTICLE COMPOSITION INSTRUMENT Particle Detector not applicable not applicable Instrument Overview =================== (excerpted from [KEPPLERETAL1992A]) The EPAC sensor will measure the fluxes, angular distributions, energy spectra, and composition of ions in the energy range from 300 keV/nucleon to 25 MeV/nucleon. The instrument generates 12 different classes of data. All events are categorised by their (dE/dx)-signal into three crude classes; their respective numbers are transmitted from three event memories. So besides the 32 event strings we also get per EDF the total number of events recorded during that time interval. Less detailed information on energy spectra are obtained with higher time resolution from 4 groups of ions. 8 energy channels are formed for each group. Bands, corresponding to the (dE/dx-E) tracks are stored in a RAM look-up table. All events are sorted accordingly for 4 ion groups (He, C-N-O, S-group, F-group). For telescopes 2 and 3 these are in addition resolved into 8 spin-sectors. A full set will be transmitted in about 34 min. If only one species is selected, time resolution increases to ~ 8.5 min. Protons are identified separately in 8 channels (3-bit PHA) using the B-detector outputs (500 keV to 1.6 MeV). All channels are resolved into eight sectors. From the A-detector's output, integral fluxes of ions are obtained. Contributions will come from ions above an energy, defined by dead-layer thickness and electronic threshold of about 145 keV. Contribution from electrons scattered through large angles may contribute to the lowest channel, but as the detector thickness corresponds to the range of ~ 25 keV electrons, its electron detection efficiency is certainly << 1. The 4 A-detector outputs are connected to the PHA through a multiplexer (as are the B-detectors). The thresholds of the PHA are adjusted such, that in 'High Gain'-Mode channel 1 to 3 'protons' (Z >= 1), in channel 4 to 5 '[alpha]-particles' (i.e. Z >= 2), in channel 6-8 'oxygen' (i.e. Z >= 6) is detected. In 'Low-Gain', the passbands are shifted one channel up: channel 1 and 2 record now Z >= 1, channels 3 to 4 Z >= 2, channels 5 to 7 Z >= 6 and channel 8 Z >= 10 particles. The latter corresponds to about 500 keV/nucleon. This class of data is obtained in 16 min. Much higher time resolution is obtained from rates, which correspond to the integral over energy of the proton and the Z >= 1 spectra. Telescopes 2 and 3 are resolved in eight sectors. The solar aspect angle varies in the course of the mission from ~ 90 [degrees] after launch to less than 11.5 [degrees] at Jupiter. It will again increase during polar passage. This means, that there will be periods, when telescopes 1 or 2 will be fully illuminated by the sun and might affect the Z >= 1 data, but not coincidence rates. Two electron channels corresponding to 100 keV <= E <= 0.4 MeV and to E >= 0.3 MeV are also formed for each telescope. These channels are defined from proper combination of dicriminator thresholds. Their energy range is, however, not very accurately defined (due to electron scattering). For heavy ions there are also 16 rate channels for each of the 4 telescopes and each of the 4 species. They are read out once every 8 minutes. For each telescope the background rates of detector B and C are transmitted, each accumulated over 4 minutes. The equivalent geometrical factor is F[B] = 1.60 cm^2 and F[C] = 6.02 cm^2. For coincidence rates of all 3 detectors the geometrical factor G = 0.08 cm^2 ster applies.