Kast Double Spectrograph User's Manual: Quick Reference

Quick Reference

General Parameters

Scale at Cassegrain focus 3.86 arcsec/mm

Arcsecs/pixel (neglecting anamorphic mag) Red Side: 0.78
Blue Side: 0.43

Monochromatic beam size (both sides) 82.6 mm

Collimator focal length (both sides) 1416 mm

Camera focal length (both sides) 188.7 mm

Approximate Range of Good Performance

Blue lens 3000-7000 Angstroms

Red lens 4000-11000 Angstroms

Decker

Predefined Settings

Position Name

0 open

1 spect

2 finger

Maximum decker opening = 145 arcsec

Slit

Slit setting (mm) 10288-200*(slit width(mm))

Slit setting (arcsec) 10288-51.82*(slit width(arcsec))

Predefined Settings

Position Name

0 open

1 0.5 arcsec

2 1.0 arcsec

3 1.5 arcsec

4 2.0 arcsec

5 2.5 arcsec

9 9.0 arcsec

Maximum slit opening = 145 arcsec

User Filter Wheel Assembly

Position Upper Lower User

0 open open open

1 -- BG14++ --

2 Spinrad NS OG570 --

3 ND 5.0 ND 6.25 --

4 ND 1.25 GG455 --

5 ND 7.5 CuSO4 n/a

6 ND 2.5 GG385 n/a

7 calcite GG495 n/a

Grisms

Grism Grooves/Blaze Straight
Through A/pix Range Nominal
Coverage

1 452/3306 4780 1.41 2890 3150-6200

2 600/4310 4340 1.02 2090 3300-5520 (matches D55)

3 830/3460 3880 0.63 1290 3200-4550 (matches D46)

Collimator Settings

Side Typical Focus Setting Range

blue 40000 3500 to 71500

red 20000 4700 to 45000

Gratings

Grating Grooves/Blaze A/pix Range Tilt Formula* Useful Range

1 600/5000 2.35 2820 2.21(c)+5631 3800-10000

2 600/7500 2.32 2780 2.29(c)+4980 3800-10000

3** 830/8460 1.70 2040 3.15(c)+5097 3800-10000

4 1200/5000 1.17 1404 4.72(c)+4178 3800-7310

5*** 300/4230 4.59 5508 1.10(c)+5716 3800-11000

6*** 300/7500 4.60 5520 1.09(c)+5742 3800-11000

* Where c is the desired central wavelength in angstroms.
** 830/8460 grating in second order yields 0.78 A/pix, range is 1020A, and the second order central wavelength is given by 6.51(c)+4260. The max tilt of 35,400 restricts lambda < 5293A.
*** Note that the 300/7500 is more efficient than the 300/4230 for all lambda greater than ~5400 A.

Polarimeter Module

Position Upper Lower User

0 open empty in

1 filter B out

2 polaroid V n/a

3 none R n/a

4 empty I n/a

Filter Trays

Position Blue Red

0 open open

1 U GG455

2 wide G GG495

3 empty OG550

4 n/a Spinrad NS

X-Y Stages

Red Side: 37 pixels/mm
Blue Side: 67 pixels/mm
Increasing setting moves to:

Side X (lambda) Y (row)

blue lower higher

red higher lower

Side Spectral Window
(nr nc sr sc) Direct Window
(nr nc sr sc)

blue 325 2048 900 0 325 320 900 800

red 180 1200 95 0 200 200 95 565

Dichroics and Mirror

To get Type

clear out

dichroic D46 or D55

mirror mirror

Support Astronomers (sa@ucolick.org)

Last modified: Fri Sep 26 10:40:42 PDT 2008

User's Guide to the Kast Double Spectrograph

Table of Contents

Quick Reference