Cosmic dust Reflectron for Isotopic Analysis (CRIA)

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Cosmic dust Reflectron for Isotopic Analysis
(CRIA)
Conceptual Design Review
Laura Brower Project ManagerDrew Turner
Systems EngineerLoren ChangDongwon LeeMarcin
PilinskiMostafa SalehiWeichao Tu
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Presentation Overview

• Introduction to Problem Loren Chang
• Previous Dust Analyzers Loren Chang
• LAMA Overview Marcin Pilinski
• Introduction to CRIA Weichao Tu
• Requirements Drew Turner
• Verification Marcin Pilinski
• Risk Laura Brower
• Current Analyses and Trades Mostafa Salehi
• Schedule Dongwon Lee

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Space is Dusty!

• Space is filled with particles ranging in size
  from molecular to roughly 1/10th of a millimeter.
  
• Dust absorbs EM radiation and reemits in the IR
  band.
• Dust can have different properties and
  concentrations, ranging from diffuse interstellar
  medium dust to dense clouds, and planetary rings.

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Interstellar dust is believed to be produced by
older stars and supernovae, which expel large
amounts of oxygen, silicon, carbon, and other
metals from their outer layers.
Clouds of dust and gas cool and contract to form
the basic building blocks for new stars and
planetary systems.

• Comets, asteroids, and collisions in the new
  planetary system produce interplanetary dust.

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Heritage

• Past instruments have focused primarily on
  understanding the flux and chemical composition
  of cosmic dust.
• Missions have focused on in-situ measurement and
  sample return.

Aerogel Collector CIDA
CDA
SDC
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Student Dust Counter (New Horizons)

• Polyvinylidene fluoride (PVDF) film sensors.
• In-situ measurement of dust flux, mass, and
  relative velocity.
• Cannot resolve smaller particles (lt 10-12 g) nor
  measure elemental composition.

lasp.colorado.edu/sdc
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Cosmic Dust Analyzer (Galileo, Ulysses, Cassini)

• Incoming dust particles ionized, then accelerated
  through electric field to detector.
• Time of Flight (TOF) used to infer elemental
  masses of constituents.
• Parabolic target is difficult to manufacture
  precisely. Low mass resolution (20-50 m/?m)

Target
R. Srama et al., The Cosmic Dust Analyzer
(Special Issue Cassini, Space Sci. Rev., 114,
1-4, 2004, 465-518)
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Stardust

• Interstellar and interplanetary dust particles
  trapped in aerogel.
• Direct sample return for analysis of elemental
  composition on Earth.
• Requires highly specialized mission.

stardust.jpl.nasa.gov
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Cometary and Interstellar Dust Analyzer(Stardust)

• Uses impact ionization principle similar to CDA,
  electric field in reflectron is parabolic,
  eliminating the need for a parabolic target.
  Improved mass resolution over CDA (250 m/?m)
• Small target area compared to previous
  instruments. Roughly 1/20th target area of CDA.

J. Kissel et al., The Cometary and Intersteller
Dust Analyzer (Science., 304, 1-4, 2004,
1774-1776)
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Large Area Mass Analyzer LAMA Concept
Sub-systems
IONIZER
Target
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LAMA Concept Sub-systems
ANALYZER (Ion Optics)
Annular Grid Electrodes
Ring Electrodes
Grounded Grid
Target
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LAMA Concept Sub-systems
DETECTOR
Detector
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LAMA Concept Operation
incoming dust particle
Example Dust Composition
Key
Species-1 Species-2 Species-3 Target
Increasing mass
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LAMA Concept Operation
dust passing through annular electrodes
dust passing through grounded grid
Data collection from detector started
t0
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LAMA Concept Operation
negative ions and electrons accelerated to target
target material also ionizes
dust impacts target and ionizes (trigger- t0)
t0
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LAMA Concept Operation
positive ions accelerated towards grounded grid
(trigger- t1)
Ions of Species-1, Species-2, Species-3, and
Target Material
t1
t0
t1
t0
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LAMA Concept Operation
positive focused towards detector
t1
t0
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LAMA Concept Operation
positive ions arrive at detector
Ions of the same species arrive at the detector
at the same time with some spread
Species-1 arrives at detector
t1
t0
t2
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LAMA Concept Operation
positive ions arrive at detector
Species-2 arrives at detector
t3
t1
t0
t2
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LAMA Concept Operation
positive ions arrive at detector
Species-3 arrives at detector
t3
t4
t1
t0
t2
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LAMA Concept Operation
positive ions arrive at detector
Ionized Target Material
Target material has characteristic peak
t3
t4
t5
t1
t0
t2
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LAMA is promising, but

• Several tasks have yet to be completed
• Dust triggering system not yet implemented.
• No decontamination system.
• System has not yet been designed for or tested in
  the space environment.

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• Cosmic dust Reflectron for Isotopic Analysis
• (a cria is a baby llama)

Hi, Im LLAMA
Hi, Im CRIA. Am I Cute?
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CRIA Project Motivation

• LAMA Development
• To scale down the LAMA instrument to a size
  better suited for inclusion aboard missions of
  opportunity. Technology Readiness Level (TRL) of
  LAMA can be further improved from level 4 to
  level 5
• Mission opportunity
• A universal in-situ instrument design is needed
  for future mission that can incorporate high
  performance and large sensitivity and can be
  adapted to various missions.

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CRIA Project Goals

• Mission Goal
• Design an instrument capable of performing
  in-situ measurements of the elementary and
  isotopic composition of space-borne dust
  particles
• Science Goal
• Detect dust particles and determine their mass
  composition and isotopic ratios
• Engineering Goals
• Design an instrument based on the LAMA concept
  that achieves the following reductions in size,
  mass, and power in order to be compatible with
  possible missions of opportunity
• Achieve a Technology Readiness Level (TRL) of
  five or higher for the instrument
• To investigate the limits of scalability of the
  instrument and determine the upper and lower
  limits of sensitivity (size between 50 and
  125) in order to provide statistical data and
  options for a variety of possible missions

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• Baseline Design
• Inherited from LAMA concept
• Triggering system
• Scaling LAMA by a factor of 5/8
• Capable of heating the target area for
  decontamination
• Capable of interfacing with a dust trajectory
  sensor (DTS)
• A closed design with a cover
• MCP detector may be changed to a large area
  detector

Heater
t2
Cover
DTS
t1
Heater
t0
t-1
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Baseline Design ?

• Specifications of CRIA and LAMA

Parameter CRIA LAMA
Effective Target Area (m2) gt0.045 0.2
Mass Resolution (m/?m) gt100 (team goal of 200) 200
Diameter (cm) 40 64
Power Consumption (W) lt10 gt10
Instrument Mass (kg) lt10 gt10
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Previous Instrument Comparison
Instrument Measurement Type Instrument Type Parameters Measured Mass Resolution Surface Area (m2)
CRIA In-Situ Time-of-Flight Reflectron Flat electrodeTarget Flux and Composition gt100 (team goal of 200) 0.13
LAMA In-Situ Time-of-Flight Reflectron Flat electrodeTarget Flux and Composition 200 0.32
SDC In-Situ PVDF Flux - 0.125
Stardust Sample return Aerogel collector Composition - 0.1
CDA In-Situ Time-of-Flight Parabolic Target Composition 50 0.1
CIDA In-Situ Time-of-Flight Reflectron Composition 250 0.005
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Requirements Top Level
1.TR1 4 The instrument shall be derived from the LAMA concept
1.TR2 1 The instrument shall measure the mass composition of dust particles with a simulated mass resolution of at least 100 m/?m Team goal 200 m/?m. Mass resolution is derived from the full width of the mass peak, m/?m t/2?t, where t is time of flight and ?t is the base peak-width.
1.TR3 3 The instrument shall be capable of mechanically interfacing with a dust trajectory sensor (DTS)
1.TR4 2 The instrument shall be designed to meet the requirements of TRL 5
1.TR5 5 The total project cost shall not exceed 25,000.00
1.TR6 6 The instrument shall be constructed and verified by 1 December 2007
1.TR7 7 Complete design documentation shall be delivered by 1 May 2007
Drew Turner
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Requirements Flowdown
Level 1 Top Level Requirements
Analyzer
Ionizer
Each includes -Functional Reqs -Performance
Reqs -Design Constraints -Interface Reqs
Level 2 System Requirements - Functional
Requirements - Performance Requirements - Design
Constraints - Interface Requirements
Detector
Electronics/CDH
Structural/Mechanical
Level 3 Subsystem Requirements
Thermal
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Requirements Levels 2 and 3

• Functional Reqs Define system functions answer
  what, when, where, and how many type
  questions about the system.
• CRIA Example 2.FR5 The instrument shall be
  capable of detecting positive and negative
  ion species.
• Performance Reqs Define how well system is to
  perform its various tasks answer how well,
  how often, and within how long type
  questions.
• CRIA Example 2.PR6 The instrument shall be
  able to record a mass spectrum from
  Hydrogen to at least m 300 (amu) and be
  independent of the triggering method.

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Requirements Levels 2 and 3

• Design Constraints Defines factors that put
  limits on the system, such as environment and
  budget.
• CRIA Example 2.DC1 The instrument shall have a
  closed design such that no light can enter
  the interior except through the field of
  view.
• Interface Reqs Defines system inputs, outputs,
  and connections to other parts of the system or
  to some other, external system.
• CRIA Example 2.IR1 The instrument shall
  provide a mechanical interface for the Dust
  Trajectory Sensor (w/ given mass,
  dimensions and COG).

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Requirement Verification Resources
ANALYSIS ANALYSIS Applicable Req
SimIon analysis of time of flight, effective target area. TR2, FR2, PR1, PR6
SolidWorks analysis of mass, structural integrity, thermal properties TR3, FR4, PR4, IR1
TEST TEST
Bell-Jar FR3, FR6, DC3
Thermal-Vacuum PR4
Vibration table TR4
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Current Analyses and Trades

• Arcing
• Preliminary calculation
• Breakdown electric field as a function of
  pressure for air
• Maximum electric field as a function of gap
  distance for inner electrode
• Reduced size increases risk of arcing
• Unexplored area The arcing in the plasma
• Material outgassing
• - Material selection to low outgassing
  specification (G-10, Noryl, ceramic, etc.)
• - More details on other material properties
  (thermal expansion, tensile strength, density,
  etc.)

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Current Analyses and Trades

• Thermal power required
• Preliminary calculation on power require to heat
  target area to 100 oC is on going
• Target design is thermally conductive
• Detector protection against UV and
  Micrometeoroids
• We calculated micrometeoroid flux at 1 AU
• UV reflection / absorption by coating instrument
  interior
• Determine impact of UV on detector performance

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Schedule
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Schedule
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Questions?
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Backup Slides
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Previous Instrument Comparison
Instrument Measurement Type Instrument Type Parameters Measured Mass Range (g) Target Area (m2)
SDC In-Situ PVDF Flux gt 10-12 0.125
Stardust Sample return Aerogel collector Composition - 0.1
CDA In-Situ Time-of-Flight Parabolic Target Composition 10-16 - 10-10 0.01
CIDA In-Situ Time-of-Flight Reflectron Composition 5 x 10-14 - 10-7 0.005
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Mass Resolution (m/?m)

• Mass resolution describes the ability of the mass
  spectrometer to distinguish, detect, and/or
  record ions with different masses by means of
  their corresponding TOFs.
• m/?m will be affected by
• The energy and angular spread of emitted ions
• Sampling rate
• m/?m t/2?t CRIA dt2ns
• Electronic noise

FWHM full width at half maximum
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Arcing

• Electric field required for arcing in a neutral
  dielectric given by Paschens Law. Nonlinear
  function of pressure and gap distance.

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Expected Impacts
For randomly tumbling object. Per NASA Technical
Memorandum 4527, p.7-3
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Possible Questions

• What is the elemental composition of cosmic dust?
• What is the dust flux and its mass dependence?
• What direction is the dust coming from?
• What are the differences in composition and size
  between interstellar and interplanetary dust?

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Schedule