urn:nasa:pds:context:instrument:vega1.puma 1.0 1.11.0.0 Product_Context urn:nasa:pds:context:instrument:puma.vega1 2021-02-24 1.0 Changed inst LIDs from u:n:p:c:i:instID.scID to u:n:p:c:i:scID.instID And per "Guide toPDS4 Context Products" v1.7, changed all lidvid_reference to lid_reference urn:nasa:pds:context:instrument_host:spacecraft.vega1 instrument_to_instrument_host Reinhard, R and B. Battrick (eds), 'Space Missions to Halley's Comet', European Space Agency ESA SP-1066, ESA Pub Div, Moordwijk, Netherlands, 1986. reference.ESA-SP1066 Kissel, J., and F.R. Krueger, The Organic Component in Dust From Comet Halley as Measured by the PUMA Massspectrometer on Board VEGA 1, Nature, 326, 755-760, 1987. reference.KISSEL-KRUEGER1987 Kissel, J., Mass Spectrometric Studies of Halley's Comet, Advances in Mass Spectrometry 1985, 175-184, 1986. reference.KISSEL1986 Kissel, J., D.E. Brownlee, K. Buchler, B.C. Clark, H. Fechtig, E. Grun, K. Hornung, E.B. Igenbergs, E.K. Jessberger, F.R. Krueger, H. Kuczera, J.A.M. McDonnell, G.E. Morfill, J. Rahe, G.H. Schem, Z. Sekanina, N.G. Utterback, H.J. Volk, and H. Zook, Compostition of Comet Halley Dust Particles From GIOTTO Observations, Nature, Vol 321, No. 6067, 336-337, 1986. 6067, 280-282, 1986. reference.KISSELETAL1986 Krueger, F.R., and J. Kissel, The Chemical Composition of the Dust of Comet P/Halley as Measured by PUMA on Board VEGA-1, Naturwissenschaften, 74, 312-316, 1987. reference.KRUEGER-KISSEL1987 Krueger, F.R., A. Korth, and J. Kissel, The Organic Matter of Comet Halley as Inferred by Joint Gas Phase and Solid Phase Analyses, Space Science Reviews, 56, 167-175, 1991. reference.KRUEGERETAL1991 Langevin, Y., J. Kissel, J.L. Bertaux, and E. Chassefiere, First Statistical Analysis of 5000 Mass Spectra of Cometary Grains Obtained by PUMA 1 (VEGA 1) and PIA (GIOTTO) Impact Ionisation Mass Spectro Meters in the Compressed Modes, Astronomy and Astrophysics, 187, 761-766, 1987. reference.LANGEVINETAL1987A Langevin, Y., J. Kissel, J.L. Bertaux, and E. Chassefiere, Impact Ionisation Mass Spectrometry of the Cometary Grains On-Board VEGA 1 and GIOTTO, VEGA 1, and VEGA 2 Spacecrafts, Lunar and Planetary Science XVIII, 533-534, 1987. reference.LANGEVINETAL1987B 'Encounters with Comet Halley, The first results', Nature, Volume 321, No. 6067, 15 May 1986. reference.NATURE321 Sagdeev, R.Z., G.A. Avanesov, I.V. Barinov, A.I. Debabov, V.A. Krasikov, V.I. Moroz, V.A. Shamis, V.I. Tarnopolski, D.A. Usikov, YA.L. Ziman, B.S. Zhukov, F. Szabo, K. Szego, A. Kondor, E. Merenyi, B.A. Smith, S. Larson, P. Cruvellier, A. Abergel, J.L. Bertaux, J. Blamont, M. Danz, D. Mohlmann, H. Stiller, and H.P. Zapfe, Comet Halley: Nucleus and Jets (Results of the Vega Mission), Advances of Space Research, 5, 95-104, 1986. reference.SAGDEEVETAL1986A Sagdeev, R.Z., G.A. Avanesov, I.V. Barinov, V.I. Kostenko, V.A. Krasikov, V.A. Shamis, K.G. Sukhanov, V.I. Tarnopolski, YU.K. Zaiko, S.I. Zatsepin, YA.L. Ziman, B.S. Zhukov, F. Szabo, L. Szabo, K. Szego, A. Balazs, G. Endroczi, M. Gardos, M. Kanyo, Z. Nyitrai, I. Renyi, P. Rusznyak, B. Smith, S. Szalai, I. Toth, L. Varhalmi, M. Zsenei, P. Cruvellier, M. Detaille, T. Nguyen-Trong, A. Abergel, J.L. Bertaux, J. Blamont, E. Dimarellis, G.N. Dulnev, G. Tsukanova, and B.I. Valnicek, TV Experiment in Vega Mission: Strategy, Hardware, Software, Proceedings of the 20th ESLAB Symposium, ESA SP-250, Vol II, 289, 1986. reference.SAGDEEVETAL1986B Solc, M., V. Vanysek, and J. Kissel, Carbon Isotope Ratio in PUMA 1 Spectra of P/Halley Dust, Astronomy and Astrophysics, 187, 385-387, 1987. reference.SOLCETAL1987 DUST IMPACT MASS ANALYZER Spectrometer not applicable not applicable Instrument Overview =================== The dust mass spectrometer measures the chemical composition, the size and the spatial density of solid particles using a time-of-flight technique, with particular emphasis on the determination of the Li, C and B isotopic ratios. The operating Principle of PUMA, illustrated in Figure 8a, is similar to that of the PIA instrument flown on Giotto. The dust particles enter through a baffle and impact on a silver target (M) at a speed of 78 km/s. The particles and a certain amount of the target material are vaporized and partly ionized. The two Vega spacecraft have different targets; one type is mounted in a cartridge as in the PIA, the second has a corrugated surface such that a larger amount of projectile ions enter the analyzer. The target is at + 1020 V; the ions are accelerated by a grid (1), which is held at a potential of -2000 V, and enter the field-free drift tube at zero potential (4). These charged particles are sent by the electrostatic reflector (5) into the second drift tube (6) and on towards the detector (7). The ions trajectories are focused by the lenses (9), (10) and (11). A set of three electrodes (12), consisting of an inner grid at +1000 V between two grids at zero potential, prevents ions with energies less than 1 keV from reaching the detector. The geometry of the reflector is designed in such a way as to bunch ions of the same species (particles with energies E>E(0) travel a larger distance than those with energies E<E(0)) and to eliminate those with energies that deviate too much from E(0). The purpose of this mirror system is to reduce the dispersion of the flight times for particles having the same charge-to-mass ratios. The reflector potential is switch- between 1000 V and 1100 V every 30 s, in order to compensate for the higher energies of ions created by the impacts of larger particles. The time-of-flight is measured with reference to three signals: the light flash recorded by the photomultiplier (3), the pulses detected by the target (M), and the accelerating grid (1). The signals induced in these sensors, in the first lens (9), in the ejecta trap (8) and in the detector (7), which are illustrated qualitatively in Figure 8c, are used to characterize the mass of the particles. Additional information about PUMA is given in the table below. Table. Dust Mass Spectrometer characteristics Target material Silver Total drift lengt 1 m Time of flight 4 micro s (H+) - 40 micro s (Ag+) Ion detector Secondary electron multiplier Dust mass range 3x10**-16 -5x10**-10 g Atomic mass range 1-110 amu Mass resolution, m/delta m, at m = 107 200 Chemical composition accuracy per spectrum 10% Maximum data acquisition rate 12 spectra/s Expected number of events 10**3-10**4 impacts during flyby