EUV and Soft X-ray Optics, Thin Films and Outer Space.

1. EUV and Soft X-ray Optics, Thin Films and Outer Space. Or what you can to do to help your local universe. David D. Allred, allred@byu.edu

2. Preparing & studying soft x-ray and EUV optical elements Over the years we have participated in a number of space and planetary physics projects. These have allowed out students to have some amazing experiences. Projects include: • The Goldhelox project in the late 80’s and early 90’s, • Preparing the boron coating for the x-ray window on the chemical analysis snout of the Sojourner Rover. This was part of the 1997 Pathfinder Mission. • The Image Mission: (It sees some of the Van Allen radiation belts.) Launched March 25, 2000

3. Sun in x ray and visible light http://solar.physics.montana.edu/YPOP/FilmFestival/index.html

4. Pathfinder Mission. • Preparing the x-ray window on the chemical analysis snout of the Sojourner Rover.

5. IMAGE Mission http://image.gsfc.nasa.gov/

6. More projects • Preparing a reflective surface for the neutral particle detector for the European Space agencies Mars Express. To be launched this year. • Uranium and thorium oxide coatings for soft x-rays (150-400 eV) astronomy mirrors. • Support for the Mars Society Desert Research Station near Hanksville. (A group of students and teachers in Utah are organizing to help.) I will focus on three of the projects (2,4 and 6) in some detail. May mention: 1. the tie in to the billion $+ future of EUV optics in microelectronic device fabrication. 2. several opportunities for undergraduate students to do important research in our area

8. Sun’s Magnetic Field

12. Earth’s Magnetic Field

13. Charged Particle in Magnetic Field

15. EM Spectrum

16. Divisions of EM Spectrum

17. EUV Pictures

18. EUV Movie of May 24, 2000 bright aurora and plasmasphere tail

19. EUV Movie of July 10, 2000

20. Tail and Shoulder: March 20,2001

21. EUV Movie of June 24, 2000

22. Mars Projects • Preparing a reflective surface for the neutral particle detector for the European Space agencies Mars Express. To be launched this year. • Support for the Mars Society Desert Research Station near Hanksville. (A group of students and teachers in Utah are organizing to help.)

23. Start Surface for Neutral Particle Detector of Mars Express Mission A near grazing incidence, antireflective coating for 121.6 nm- Spencer Olson*, David Allred, Matt Squires, Douglas Markos, Cynthia Mills and R. Steven Turley- Brigham Young University, *now at University of Michigan

24. Planet Mars • Third brightest object in the sky

25. Fundamental Considerations: • Did Water Once Exist on Mars? • Does Water Now Exist on Mars? • Can Water Ever Exist on Mars? Water is the most fundamental ingredients to life. Therefore, if we, as humans, want to decide whether life, our own or otherwise, can exist for longer periods of time on Mars, we must determine whether this basic necessity of life can be found on Mars.

26. Riverbeds River canyons Evidence: Existing evidence of water on Mars comes in the form of visible riverbeds and river canyons.

27. The question is then, if we can see that there is a history of water on the surface of Mars, where has all of this water gone? Several speculations state that the water exists frozen beneath the permafrost of the planets surface. Another speculation is that water on Mars evaporated into its atmosphere where it was then literally blown away by the solar wind.

28. Solar Wind Solar wind is comprised of • Neutral and Charged Particles Emitted From the Sun. This stream of particles, or the solar wind, then • Interacts With Atmospheres of Planets in Space. Examples of this can be seen when a comet’s tail is blown away from the direction of the sun.

29. Mars Express - 2003 In 2003, the European Space Association (ESA) plans to launch a spacecraft to Mars that will aid in determining the possibilities water.

30. Energetic Neutral Particle Analyzer One of several instruments on the ESA spacecraft, the Energetic Neutral Particle Analyzer contains a time-of-flight neutral particle detector (NPD). The purpose of this instrument is to study the effect of the solar wind on the atmosphere of Mars. To do this, the NPD will measure the momentum with which neutral particles in the solar wind might bombard atmospheric particles, thus showing how much the solar wind might erode the atmosphere of Mars.

31. Neutral Particle Detector (NPD) When a particle enters into the NPD it reflects off of a surface, labeled the Start Surface. Upon impact on the Start Surface, an electron (depicted as e-) is emitted from the surface and attracted by an electric field to a detector labeled the Start Detector, whereon a timer is started. The neutral particle continues on after reflection until it hits a detector labeled Stop Detector, whereon the timer is stopped. The speed of the particle is then calculated using sixth grade physics speed = distance / time.

32. BYU’s Participation Energetic light, entering the orifice of the instrument, may also reflect on the Start Surface and create false stop signal in the Stop Detector. In space, there is an abundant supply of vacuum ultraviolet photons (especially 121.6 nm=10.2 ev), which is energetic enough to cause this effect. The XUV Research Group of BYU was asked to provide a solution to this problem. The remaining portion of this presentation will focus on BYU’s efforts in designing, this surface.

33. Absorption of Light withUltrathin Multilayers A common method for controlling light is the use of a thin film. A thin film is just what we expect it to be; it is a very thin layer of some material. The principle for making an optic with thin films lies in the fact that there can be many interfaces where light can be reflected. For the Start Surface, the superposition of these many reflections must result in a minimum amount of light leaving the surface. An example of a thin film causing similar interference, with which we are all familiar, is that of oil on a puddle, on a rainy day.