MagE Commissioning: November 2007 and January 2008

MagE Commissioning: November 2007 and January 2008

Scott Burles, Ian Thompson

Steve Shectman, Jennifer Marshall

Bruce Bigelow, Matt Smith

Christoph Birk, Patricio Jones

Greg Burley, Jorge Estrada

Vince Kowal, Robert Storts

Jerson Castillo

MagE Characteristics

• Broad wavelength coverage for a single object (3100 Å - 1 micron) optimized for the UV ( < 4000 Å)

• Moderate resolution, R = 4200 with 1” slit

• Slit length 10” (0.3” per pixel)

• Slit widths of 0.5, 0.7, 0.85, 1.0, 1.2, 1.5, 2.0, 5.0” + pinholes for focusing

MagE Characteristics

• High spectrograph efficiency:

Goal of 30% including telescope (on blaze)

• Very simple operation and maintenance:– Only moving parts are slitmask, flip mirror,

shutter and collimator focus– Cryotiger cooling

Credit B. Bigelow

MagE Structure and Optical Layout

Off-axis paraboliccollimator

32.3 degree blazediffraction grating

Double-passprism

Schmidt sphericalprimary, f/1.4140mm FL

C1

C2

Focalplane

Rotatormount

Single-passprism

Field flattenerand CCD

Credit S. Shectman

Optical Layout of MagE

7000 Å

3200 Å 4000 Å

1 m

Zemax spotDiagrams

• e2v 42-20 2048x1024x13.5m• Dewar vacuum is maintained with •Varian 2 l/s Ion pump and has reached a vacuum level of 1.4x10-6 mbar, and should last a minimum of 2.5 years.• Both cryotiger cold head and CCD aluminum mount have temperature sensors. In the lab, the cold head reaches -156C and the CCD mount reaches -110C. Dark rate at this temp is 14 e-/pix/hour with ion pump running and is less than 2 e-/pix/hour under dark conditions with the pump off.•Three readout speeds:

MagE CCD Performance

Read speed Read time (s) Gain (e-/DN) RMS noise (e-)

Slow 33 1.02 2.9

Fast 21 0.82 3.1

Turbo 14 1.53 4.2

MagE ThroughputOrder Lambda Dlambda Zeropoint Extra Extinction Efficiency Efficiency

(Å) (Å) (1 ct/s/Å) Flux (Instrument)

20 3125 0.231 17.504 0.191 1.523 0.091 0.171

19 3260 0.244 18.434 0.046 0.952 0.116 0.217

18 3440 0.258 18.791 0.036 0.587 0.12 0.225

17 3650 0.274 19.042 0.042 0.464 0.144 0.270

16 3860 0.292 19.212 0.025 0.37 0.161 0.302

15 4130 0.311 19.438 0.026 0.291 0.198 0.370

14 4400 0.335 19.461 0.024 0.215 0.2 0.375

13 4750 0.36 19.491 0.007 0.176 0.211 0.396

12 5140 0.39 19.503 0 0.114 0.217 0.406

11 5590 0.426 19.415 0 0.117 0.218 0.408

10 6130 0.469 19.316 0 0.085 0.212 0.397

9 6800 0.521 19.125 0 0.028 0.187 0.351

8 7520 0.59 18.682 0 0.004 0.135 0.252

7 8610 0.674 18.057 0 0.149 0.099 0.185

6 9700 0.788 16.3 0 0.027 0.02 0.037

The MagE solar echellogram

•Preliminary wavelength solution yields 0.063 Å (4 km/s) rms

over 13 orders with a 0.7” slit

A Thorium-Argon Hollow-Cathode image

• Spots have FWHM less than 2 pixels over full frame

MagE spot diagrams in lab

The MagE GUI

First Light!

MagE Usage 2008A

• 18 nights MagE only

• 21 nights MagE + other instrument

• 39 total nights scheduled

MagE To Do List

• Replace CaF2 corrector– It was cracked in coating procedure

• Data reduction pipeline functioning– Still work to do in defining optimal flat fields

• May replace Xe flash lamp