Particles and Fields Package PFP Instrument Preliminary Design

Particles and Fields Package (PFP) Instrument Preliminary Design Review Science David L. Mitchell PFP IPDR 2010/6/14 - 16 1

MAVEN Science Questions MAVEN will determine the role that loss of volatiles to space has played through time, providing definitive answers about Mars climate history: • What is the current state of the upper atmosphere and what processes control it? • What is the escape rate at the present epoch and how does it relate to the controlling processes? • What has the total loss to space been through time? PFP IPDR 2010/6/14 - 16 2

MAVEN Mission Architecture • In situ and semi-global remote sensing measurements are made from the MAVEN elliptical orbit. • Measurements are obtained down to the well-mixed lower atmosphere through five “deep dip” campaigns. • Coverage of all local solar times and most latitudes, along with broad geographical coverage, results from precession of the MAVEN high-inclination orbit. PFP IPDR 2010/6/14 - 16 3

MAVEN Measures Drivers, Reservoirs, and Escape Rates Solar Inputs Plasma Processes LPW SWIA STATIC SWEA MAG IUVS EUV SEP SWIA Neutral Processes SWEA NGIMS MAG IUVS PFP IPDR 2010/6/14 - 16 4

The MAVEN Payload Makes the Essential Measurements NGIMS IUVS LPW integrated analysis STATIC MAG, SWEA, SWIA, LPW SEP LPW - EUV PFP IPDR 2010/6/14 - 16 5

STATIC Measurement Requirements • STATIC measures Low- and medium-energy ion composition, energy, and direction: – Densities, velocities, and temperatures of suprathermal H+, O 2+, and CO 2+ above the exobase with the ability to spatially resolve magnetic cusps • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 55 STATIC Flux Range 1 MRD 52 STATIC shall measure energy fluxes from 1 E 7 to 1 E 10 e. V/cm 2 -sec-ster-e. V with 20 second resolution PF 56 STATIC Flux Range 2 MRD 53 STATIC shall measure energy fluxes from 1 E 4 to 1 E 8 e. V/cm 2 -sec-ster-e. V with 30 minute resolution PF 57 STATIC Mass Range MRD 54 STATIC shall measure ions from at least 1 -44 amu PF 58 STATIC Mass Resolution MRD 55 STATIC shall have mass resolution m/dm of at least 2 PF 59 STATIC Energy Range MRD 56 STATIC shall measure ions from 1 to 10, 000 e. V PF 60 STATIC Energy Resolution MRD 56 STATIC shall have energy resolution d. E/E of at least 30% PF 61 STATIC Angular Resolution MRD 56 STATIC shall have angular resolution of at least 30 degrees PF 62 STATIC FOV MRD 57 STATIC shall have a FOV at least 60 degrees by 180 degrees PF 63 STATIC Time Resolution 1 MRD 52 STATIC shall have time resolution of 20 seconds or better for Flux range 1 PF 64 STATIC Time Resolution 2 MRD 53 STATIC shall have time resolution of 30 minutes or better for Flux range 2 PFP IPDR 2010/6/14 - 16 6

SWEA Measurement Requirements • SWEA measures properties of solar wind electrons that can drive escape: – Energy distributions of solar wind, magnetosheath, and ionospheric electrons to determine the electron impact ionization rate, with an energy resolution sufficient to distinguish ionospheric photoelectrons from solar wind electrons – Electron angular distributions to determine magnetic topology, with the ability to spatially resolve magnetic cusps. • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 65 SWEA Flux Range MRD 58 SWEA shall measure energy fluxes from 1 E 4 to 1 E 8 e. V/cm 2 -sec-ster-e. V PF 66 SWEA Sensitivity MRD 59 SWEA shall have a geometric factor > 0. 005 cm 2 -ster PF 67 SWEA Energy Range MRD 60 SWEA shall measure electrons from 10 - 1000 e. V PF 68 SWEA Energy Resolution MRD 60 SWEA shall have energy resolution d. E/E of at least 25% PF 69 SWEA Time Resolution MRD 61 SWEA shall have time resolution of 20 seconds or better PF 70 SWEA Angular Resolution MRD 62 SWEA shall have angular resolution of at least 45 degrees PF 71 SWEA FOV MRD 63 SWEA shall have a FOV which covers at least 50% of the sky PFP IPDR 2010/6/14 - 16 7

SWIA Measurement Requirements • SWIA Measures properties of solar wind ions that can drive escape: – Density and velocity distributions of solar wind and magnetosheath ions to determine the charge exchange rate and the bulk plasma flow from solar wind speeds down to stagnating magnetosheath speeds • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 72 SWIA Flux Range MRD 64 SWIA shall measure energy fluxes from 1 E 7 to 1 E 10 e. V/cm 2 -sec-ster-e. V PF 73 SWIA Flow Velocity MRD 65 SWIA shall measure ion flow velocities from 100 -1000 km/s PF 74 SWIA Energy Resolution MRD 66 SWIA shall have energy resolution d. E/E at least 15% PF 75 SWIA Angular Resolution MRD 67 SWIA shall have angular resolution of at least 30 degrees (10 degrees in Sun direction) PF 76 SWIA Time Resolution MRD 68 SWIA shall have time resolution of 1 minute or better PF 77 SWIA FOV MRD 69 SWIA shall have a FOV of 180 x 40 degrees or better PFP IPDR 2010/6/14 - 16 8

SEP Measurement Requirements • SEP Measures solar energetic particle input into upper atmosphere: – Solar energetic particles that can interact with the upper atmosphere, with a time resolution sufficient to capture SEP events. • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 78 SEP Flux Range MRD 74 SEP shall measure energy fluxes from 10 to 1 E 6 e. V/cm 2 -sec-ster-e. V PF 79 SEP Energy Range MRD 75 SEP shall measure ions from 50 ke. V to 5 Me. V PF 80 SEP Energy Resolution MRD 76 SEP shall have energy resolution d. E/E of at least 50% PF 81 SEP Time Resolution MRD 77 SEP shall have time resolution of 1 hour or better PFP IPDR 2010/6/14 - 16 9

MAG Measurement Requirements • MAG measures solar-wind interactions and “mini-magnetospheres” – Vector magnetic field in the unperturbed solar wind, magnetosheath, and crustal magnetospheres, with the ability to spatially resolve crustal magnetic cusps. • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 82 MAG Dynamic Range MRD 70 MAG shall measure magnetic fields from 3 to 3000 n. T PF 83 MAG Accuracy MRD 71 MAG shall have an accuracy of better than 1% over its dynamic range PF 84 MAG Resolution MRD 72 MAG shall have resolution of better than 1% over its dynamic range PF 85 MAG Time Resolution MRD 73 MAG shall have time resolution of 20 seconds or better (5 seconds below 400 km) PFP IPDR 2010/6/14 - 16 10

LPW Measurement Requirements • LPW shall measure electron temperature and number density measured in situ: – Thermal electron density and temperature from the ionospheric main peak to the nominal ionopause with a vertical resolution of one O 2+ scale height. • LPW shall measure electric field wave power – at frequencies important for ion heating. • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 86 LPW Density Range MRD 45 LPW shall measure electron densities from 1 E 2 to 3 E 5 cm-3 PF 87 LPW Density Accuracy MRD 45 LPW shall have density accuracy dn/n of at least 10% PF 88 LPW Temperature Range MRD 46 LPW shall measure electron temperatures from 0. 01 to 0. 5 e. V PF 89 LPW Temperature Accuracy MRD 46 LPW shall have temperature accuracy d. T/T of at least 10% PF 90 LPW Frequency Range MRD 47 LPW shall measure waves from 0. 05 to 10 Hz PF 91 LPW Wave Power Sensitivity MRD 47 LPW shall have wave power sensitivity of at least 1 E-8 (V/m)2/Hz PF 92 LPW Spatial Resolution MRD 48 LPW shall have time resolution of 15 seconds or better PFP IPDR 2010/6/14 - 16 11

EUV Measurement Requirements • EUV shall measure solar EUV input into upper atmosphere: – Solar EUV irradiance at wavelengths important for ionization, dissociation, and heating of the upper atmosphere with a time resolution sufficient to capture solar flares. • Derived Level 3 measurement requirements: ID Title Parent ID Description PF 93 LPW/EUV Saturation Current MRD 49 LPW/EUV shall have saturation current resolution dl/l of at least 15% PF 94 LPW/EUV Photodiode Current MRD 50 LPW/EUV shall have photodiode current resolution dl/l of at least 15% PF 95 LPW/EUV Time Resolution MRD 51 LPW/EUV shall have time resolution of 10 minutes or better PFP IPDR 2010/6/14 - 16 12

PF Instrument Backups PF Instrument Primary Backups Secondary Backups NGIMS IUVS STATIC, LPW IUVS NGIMS EUV LPW NGIMS (Ne) STATIC (Te), MAG (waves) EUV LPW SWEA, Earth-based STATIC SWIA SWEA SWIA STATIC, SWEA SEP SWEA, SWIA, STATIC MAG PFP IPDR 2010/6/14 - 16 STATIC, LPW SWEA 13

PF Measurement Resiliency If we lose any one instrument, do we lose any high-level objectives? (Y = Yes, S = Substantial, P = Partial, N = Not significant, - = Minimal contribution) Objective 1 Instrument PF Objective 2 Objective 3 Current State Processes Escape Rates Processes Evolution NGIMS N - N N N IUVS N N N P N STATIC - N S S N SEP - N N SWEA N N N SWIA - N N LPW N N N EUV - N N MAG N N N PFP IPDR 2010/6/14 - 16 14