Compact Dual Ion Composition Experiment (CoDICE)

CODICE


CoDICE Instrument

 

Like its sister instrument Solar Wind and Pickup Ions (SWAPI), the CoDICE instrument collects and counts two types of particles: ones from the solar wind flowing from the Sun and particles called pick-up ions (PUIs) that entered the heliosphere from outside our solar neighborhood and traveled inwards where IMAP orbits about a million miles from the Earth. The solar wind particles CoDICE collects and sorts are highly energized particles, called suprathermal particles, which are moving faster (and therefore have higher energy) than the solar wind particles that SWAPI collects. CoDICE also simultaneously measures the velocity, direction of travel, energies, and types of specific species of PUIs from the local interstellar medium. Some of these are hydrogen and helium ions like SWAPI, but CoDICE is also able to collect and analyze heavier ions than SWAPI can.

How It Works

CoDICE has two different collimators – one for the solar wind ions and PUIs (CoDICE-Lo) and one for the energetic suprathermal particles (Co-DICE-Hi). As IMAP spins in space, PUIs and charged solar wind ions flow into CoDICE-Lo through the ring of openings at the head of the instrument that leads into the sphere-shaped electrostatic analyzer (ESA). The ESA uses charged plates that allow the passage of only those ions that have a specific energy, concentrating them into a smaller space and accelerating them. Ions with energies either larger or smaller than the chosen setting crash into the walls of the ESA, but if they have exactly the right amount of energy, they flow down to impact onto a carbon foil where some electrons can be knocked loose.

These secondary electrons are steered upward toward a micro channel plate (MCP) that multiplies the number of electrons. Because electrons are so tiny, even a group of 1000 would not have a big enough charge for a sensor to pick up, so the charges need to be multiplied, or increased, to be detected. Each channel in the plate can multiply an electron many times. An electrical impulse is recorded that counts the ions that entered through the foil, as well as records the time they flew into the detector. The PUIs and solar wind ions continue on a path through the foil towards one of 24 avalanche photodiodes (APDs). The ADPs transform the ions into an electrical pulse that records their energy and counts their number and the direction they came from in the sky. Secondary electrons can also be knocked off when the ions crash into an ADP. These electrons are steered downward to another MCP that records the time that they impacted. IMAP scientists can compare the time difference between when the first electrons connected with the top, or start, MCP and when the second electrons impact on the lower, or stop, MCP. The time difference tells scientists how fast the ions are moving, and when combined with the energy measurement from the APDs, determine how big, or heavy, the ions are and identify their type, or species.

Simultaneously, highly energetic suprathermal particles are funneled into one of the 12 trumpet shaped collimators of CoDICE-Hi that rings the bottom of CoDICE’s ESA apparatus. Because they are already traveling super-fast with a lot of energy, they do not need an ESA to accelerate them and flow directly to the same carbon foil that the ions from Co-DICE-Lo pass through. Like, the PUIs and solar wind ions, secondary electrons from the suprathermals follow a parallel path to the start MCP to have their start times recorded while the intact ions crash into silicon solid-state detectors (SSDs) that record their energy, number and the direction of origin. Secondary electrons from the SSD impacts flow down to the stop MCP to have their end times recorded and transmitted to Earth. IMAP scientists use this data, like the PUI and solar wind ion data, to determine what species the suprathermals are composed of.

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Explore the CoDICE Model

How We Use CoDICE Data

IMAP scientists use the data from CoDICE along with data from SWAPI to better determine the origin of areas of highly energetic particles that arise throughout the solar wind and advance the understanding of the acceleration of particles in the heliosphere. 

 

Meet the Team

CoDICE is led by Stefano Livi of Southwest Research Institute (SwRI). The CoDICE team is composed of ~ 12 engineers, 12 scientists, and 1 computer scientist. In addition, SwRI is managing the payload and payload systems engineering and supporting the development of other IMAP technology for the mission. 

SwRI collaborates in the design, assembly, and delivery of three additional IMAP instruments, IMAP-Hi, IMAP-Lo, and Solar Wind Electrons (SWE) with John Hopkins University Applied Physics Laboratory (APL), Los Alamos National Laboratory (LANL), University of New Hampshire (UNH), and University of Bern (UBe)

Hey guys, congratulations! Our instrument works great!

- Keiichi Ogasawara, Instrument Scientist, The Compact Dual Ion Experiment (CoDICE) instrument on the IMAP spacecraft measures the quantities and concentrations of interstellar pick-up ions that have passed through the heliosheath from outside the solar system. CoDICE also collects and characterizes solar wind ions, including suprathermals., after obtaining triple coincidence measurements for the first A measure of the flow of events..

Creating this instrument was a journey, filled with challenges that tested our resolve. From navigating persistent noise issues to dealing with the risk of ESD damage to the ASICs, each obstacle pushed us to innovate and adapt. Yet, through it all, I found a deep sense of pride in the final product we've crafted, a testament to the hard work and dedication of our team. 

- John Trevino, Electrical Engineer, The Compact Dual Ion Experiment (CoDICE) instrument on the IMAP spacecraft measures the quantities and concentrations of interstellar pick-up ions that have passed through the heliosheath from outside the solar system. CoDICE also collects and characterizes solar wind ions, including suprathermals. 

Recently, engineers Guy Grubs and John Trevino dedicated a week to investigating various pulse injections into the The Compact Dual Ion Experiment (CoDICE) instrument on the IMAP spacecraft measures the quantities and concentrations of interstellar pick-up ions that have passed through the heliosheath from outside the solar system. CoDICE also collects and characterizes solar wind ions, including suprathermals. instrument. In a final attempt, they introduced a random signal, and almost immediately recognized the 'ghost peak' they had been meticulously searching for. Their efforts culminated in successfully resolving the issue, much to the relief and satisfaction of the team. 

- Heather Elliot, Instrument/Science Teams, The Solar Wind and Pickup Ion (SWAPI) instrument collects and counts solar wind particles and pick-up ions (PUIs). and CoDICE

CoDICE Team Standing in Front of a Building

The CoDICE Instrument Team.