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MOSFIRE


This page has been updated for cooldown #8 (Dec 20th 2010):

The MOSFIRE front end (with npk in reflection). The top lens is the guider, the bottom flat is MOSFIRE's front window. MOSFIRE is enormous.

The MOSFIRE detector head, inspection using the coordinate measuring machine (CMM) begins.

The MOSFIRE pinhole mask, used to determine best focus, flexure, and the plate scale, is being inspected in the lab on the CMM.


Pre Cooldown #5 Images:
MOSFIRE is a near infrared spectrograph for the Keck Telescope.  From September 2009 to now (Dec 2009) I have been responsible for all things optical.  Harland Epps produced a beautiful prescription, and we've had to assemble to fit.  The extremely hard hands-on work is really done by the talented duo of Jason Fucik (Caltech) and Ted Aliado (UCLA).  You can see Jason's hands in the picture below.  Oh, and extremely  hard means that a lens' position cannot deviate by more than the width of a human hair.

What does the above paragraph mean?

1) take a lens that looks like this:

2) bond it into a lens cell:


3) stick these cells together to form a barrel:

This picture captures the whole MOSFIRE lens bonding "team" left to right is Ted Aliado, Jason Fucik, & Nick Konidaris.  In the middle of the picture is the star of our show, MOSFIRE camera lenses 1 - 4.  These lenses cost several hundred thousand dollars.  Jason sits under the bridge of UCLA IR lab's Coordinate Measure Machine (CMM).  When the camera is complete, light will come up through the table and come to a sharp focus somewhere above those four lenses.

The above photo was taken shortly after the lens barrel was flipped.  MOSFIRE's camera is composed of seven lenses.  These lenses are made of exotic glasses and crystals, polished to exacting levels by Jenoptik's opticians, and then coated with fancy anti reflection coatings. 

Flipping of MOSFIRE Lenses



4) put the barrels into the main instrument (coming soon).
 As of January 2010 the Camera barrel (camera lens 1 - 6) is assembled!


The Grating

The MOSFIRE Grating was bonded in January 2010.  The picture below shows our grating illuminated with a laser.  The blazed order is shown next to my thumb.


MOSFIRE Detector Head

With the talent team of George Brims (UCLA), Ian Mclean (UCLA), Greg Mace (UCLA), I have been heavily involved in the opto mechanical aspects of MOSFIRE's detector head.
Above is MOSFIRE's detector head, inside a a cryogenic dewar, with a second surface glass mirror.  The mirror is used to test the performance of the detector as it is pushed through focus.  The I-beam structure is a flexture that maintains the parallelism of that front mirror to less then a few arcseconds throughout the focal range.

 
 



The above pictures show the assembled MOSFIRE detector head, including camera #7 (in the black box), the detector (hidden under the lens), and a small thermal link jutting out from the left.  On the right you see a profile of the detector head along with (from left to right) Ted Aliado (UCLA), Kristin Kulas (UCLA), and Ian McLean (UCLA) -- the detector head gurus.

MOSFIRE Alignment

MOSFIRE is a demanding spectrograph.  The optics inside the dewar have to maintain excellent alignment.  To reduce the thermal background, MOSFIRE is maintained at 120 degrees Kelvin.  This means that most "typical" methods for aligning the telescope are difficult.

To measure the alignment of MOSFIRE, we assembled a suspended platform from the clean room's ceiling:
Above is Jason Fucik looking through the alignment telescope, measuring the displacement of MOSFIRE's internal crosshairs.  Jason and I spent a full week alternately suspended on this platform ensuring MOSFIRE's alignment.

The view from the top of the platform is:


MOSFIRE Camera Installation!

The MOSFIRE camera was install on April 15th, tax day.  This was the culmination of several man years of work.  Some pictures from the event:


MOSFIRE Camera Lens Slideshow




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