LDEX in CCLDAS Accelerator

Hi Everyone,

LDEX in LEIL

David James and Keith Drake putting
LDEX into LEIL

It's been a while.  I'll try to make sure we get more regular updates.  In the meantime, something exciting happened recently, we have LDEX inside the LEIL target chamber and we were firing on it this past weekend (ugh yup, grad students don't get vacation...).  They're still doing some tests on it while it's under vacuum, but will hopefully be done sometime this week.

LEIL under vacuum with the laser
shining onto it

The good news though is that the particle selection unit seems to be doing its job in selecting particles.  We discovered, however, a bunch of particles still made it to LDEX despite the fact that they did not appear on our detectors.

For those who don't know, LDEX is the Lunar Dust EXperiment that will be flying aboard the Lunar Atmosphere and Dusty Environment Explorer (LADEE) mission in 2013.  It can measure the charge and mass of dust particles and will hopefully enlighten us on the density of dusty plasma in the terminator regions of the moon.

Shu

More SEM Images

Hi Everyone,

Here are some more cool SEM images of glass samples that we fired at.  As you can see we've got some larger structure around the micron crater.  Also, previous to this, I had only been able to find 3um craters which I thought was odd.  I have now found craters on the submicron scale.  These guys are really tough to find and image.  I'll hopefully have more images and a couple more details on them in the near future.

Shu

Small crater <1um.  These guys are really tough to image.

SEM image of dust damage on glass.  Crater is about 2 um.

First Dust Impact Sites

First dust impact, average diameter of 3.84 microns.

Hi Everyone,

We had our first customer come to the accelerator.  Mr. Doug Currie from the University of Maryland was studying dust impacts on samples of polished fused silica glass to see what kind of damage micrometeorite impacts would do to the glass.  After firing about 3000 shots onto a 1" diameter piece of glass, we took the sample to a scanning electron microscope (SEM).  This is one of the craters we found on the surface.  It has an average diameter of 3.84 microns.  The dust we fired at it ranged from 0.4-6 microns in diameter and a velocity of 1-3 km/s.  I'm hoping to get more time with the SEM and a good optical light microscope to get a better idea of what we did to the surface.

Shu

Future of Space Flight Symposium

Hi everyone,
I apologize for the long hiatus, I've been working on my second comprehensive exam so I haven't had much time to blog.  Coincidentally, on the 29th of April, we at CCLDAS will be hosting a public symposium on the Future of Commercial Space Flight.  Check the flier above for details.  If you can't make it, you can still watch the symposium by going to http://www.ustream.tv/channel/the-future-of-commercial-space-flight.  Hope to see you all there!
Shu

Dust to the End!

I am very pleased to announce that we successfully ran the accelerator today at 2MV with signals all the way to the last detector (great job with the alignment guys!). I have attached an image of one of the faster but typical signals. The blue is the first detector, red third, and the black is the final detector (we also used the second detector for a time but only have three power supplies at this point). Please enjoy the picture! Congrats everyone, this is another huge step!

If you have been following, by now you know that our accelerator is up and running and very close to being finished. What you may not know it that all of this work could not have been completed without the dedicated work of Kurt Kapfhamer from NEC (it would have easily taken us months rather than weeks). Two weekends ago we took some time to show Kurt some of beautiful Colorado in Estes Park. We saw some elk, ate trout, and even walked on a frozen lake.Stay tuned for more updates!

Success!!

Hi Everyone,

The Pelletron has been charged up to 3 million volts!

We did a bit more work on the Pelletron today, filling the tank all the way up to 80PSI of SF6.  We also tried running up the voltage on the Pelletron and was able to get it up to 3 million volts!  Unfortunately it started sparking at this point, which is normal.  It sounds a bit like a gun but a little quieter.  We've got it now at about 2.5 million volts and we'll be "conditioning" it all night.  This really just means we'll leave it running and any of the rough edges or dust still left inside the high voltage terminal will be blasted away by the sparks that are created.  With any luck, the Pelletron will be fully functioning tomorrow morning.  Keep your fingers crossed!

Shu