CHAMP:Manual

Manual for the CHARA-Michigan Phasetracker

Overview

Tools	Username@Computer	Command	Comments
CHAMP server	champdev@champ	~/champ_server
CHAMP spooler	champdev@champ	~/champ_spooler
Filters GUI	devel@wolverine	~/filtergui
Picomotor GUI	devel@wolverine	~/picogui
Fringe Tracking GUI	devel@wolverine	~/ftgui
Infrared camera GUI	devel@wolverine	~/ircamgui
ESP GUI	observe@zoot	espgtk RETRO	server command in /etc/rc.d/rc.local
Shutter GUI	observe@zoot	shutgtk

Computer	IP
champ	192.168.3.136
wolverine	192.168.3.143
zoot	192.168.3.31
lothlorien	192.168.3.134
ctrscrut	192.168.3.3
mirkwood	192.168.3.131

Quick Startup Guide

How to log into CHAMP for development.

1) Power on outlets

Open in a web browser the CHAMP and MIRC APC controls: Use Immediate Turn On for:

• CHAMP scanning PZTs

• CHAMP Electronics

• CHAMP picomotors (#1, 2, 4 in the list).

• MIRC MOXA Serial Port box.

2) Launch CHAMP server (fringe tracking and camera engine)

3) Launch CHAMP spooler (data saving)

4) Launch the infrared camera GUI

Once the IR Camera gui appears:

• click Update DAQ in the FPA Tab.

• click Update Server in the FT Tab.

• click Config Camera in the FPA Tab.

• click Start Exposure in the top bar.

The camera will start acquiring frames.

4) Launch the Fringe Tracking GUI

Alignment

Nightly Alignment

Start the shutters and picomotors GUI.

Internal fringes

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RETRO FRINGES

• Start the retro-reflector GUI.
• Press RETE1 (becomes green), home it, select step size of 4 microns (0.004).
• for automatic RETRO search, use acceleration = 0.1, and vel=0.02.

Past results (+/- around 0.1 mm repeatability) with the pickoff mirrors in fiducial position (mount and platform aligned manually):

BC: 58440

IR1 175910

IR2 172160

IR3 173123

IR4 172835

IR5 210017 (because of cable which pulled the platform), new value to adopt 173756

W1W2 on B1B2: 3.15 mm -- May 18 2011: 2.95 mm

W1W2 on B2B3: 6.84 mm

W1W2 on B3B4: 3.28 mm -- May 17 2011: 3.12 mm for CHAMP and MIRC 4.51 mm (MIRC fiducial position)

W1W2 on B4B5: 5.70 mm -- May 18 2011: 5.14 mm for CHAMP

W1W2 on B5B6: 10.36 mm (found with IR5 210007 and BC at 0) -- May 18 2001 10.38 for champ

W1W2 on B6B1: not found

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INTERNAL FRINGES WITH DELAYLINES

Jan 2011: Using Delaylines+ new delayline retros

W1 2.2000

W2 2.0079

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Full Alignment

STEP 1

• Turn on the CHAMP alignment laser (red) on the CHAMP table
• Align each beam on R1 target using A0
• Align on L1 using A1
• Align on R2 using A2, putting blocker on R1 (using L1/L2-target), so you don't see two spots
• Align on target L2 using A3, putting blocker on L1 (using the R1/2-target).

STEP 2

• Remove all blockers, put a blocker on R1
• Align on Towers of Power 1 and 2 using R1-R6
• Remove all blockers, put a blocker on L1
• Align on Towers of Power 3 and 4 using L1-L6 mirrors
• Align on Tower of Power 1-2 using beam splitter A4
• Check the alignment on Tower of Power 3-4

STEP 3

• Put camera target in front of camera
• Align on camera target using the Towers of Power and the cheat sheet: each spot should be near the edge of the pyramid, so that it's nearly jumping if you move the mirror knobs.
• Turn off the alignment laser

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Setting up camera to align spots

Last step is to align the picomotor actuated mirrors using the actual infrared images.

Here are two setup configurations for reading out camera -- a widefield mode and a standard mode.

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Wide field mode:

Rows: 100

Cols: 100

row off: 1

col off: 1

nreads : 4

nframes: 20

framesperreset:10

Fringe tracker speed: 3 Hz.

Pyramid Apex: [to be confirmed:] 8,4

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"Normal" Readout

Rows: 16

Cols: 16

Row off: 8

Col off: 20

nreads : 10

nframes: 42

framesperreset: 21

FT:

Freq 29.2571

Amp 10.5

OPD 13.2

Smooth: .05

Delay 0.0

(center of pyramid on wide-field image: 23, 8)

(2010Jul: row off: 7, col off: 9, freq: 30)

Jan 2011 row off:8, col off: 20, freq: 29.2571

May 2011 row 7 col 22

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Shutters, spot pico ordering for alignment

using white light and K' filter.

Method for aligning spots on camera for 4 beams configuration

Step	Open Shutter	Spot	Pico [alternate]	Comments (To be confirmed)
1	B1	L1	Dicroic 1 (or T3H)
2	B1	R2	T2H	top spot
3	B2	L2	Dicroic 2 (or T3M)	top spot
4	B2	R3	T2M	bottom spot
5	B2	R2	BC1-2	top spot
6	B3	L3	Dicroic 3 (or T4H)	bottom spot
7	B3	R4	T1L	top spot
8	B3	R3	BC2-3	bottom spot
9	B4	L4	Dicroic 4 (T4M)	top spot
10	B4	R1	T2L	top spot
11	B4	R4	BC3-4	top spot
12	B4	L1	BC6-1	bottom spot

Method for aligning spots on camera for 6 beams configuration

Step	Open Shutter	Spot	Pico [alternate]	Comments (To be confirmed)
1	B1	L1	Dicroic 1 (or T3H)	top spot
2	B1	R2	T2H	top spot
3	B2	L2	Dicroic 2 (or T3M)	top spot
4	B2	R3	T2M	bottom spot
5	B2	R2	BC1-2	top spot
6	B3	L3	Dicroic 3 (or T4H)	bottom spot
7	B3	R4	T1L	top spot
8	B3	R3	BC2-3	bottom spot
9	B4	L4	Dicroic 4 (T4M)	top spot
10	B4	R5	T1H	bottom spot
11	B4	R4	BC3-4	top spot
12	B5	L5	Dichroic 5	brightest spot (right)
13	B5	R6	T1M	should be clean
14	B5	R5	BC4-5	bottom spot
15	B6	L6	Dichroic 6	should be clean
16	B6	R1	T2L	top spot
17	B6	R6	BC5-6	should be clean
18	B6	L1	BC6-1	???

Pictures

Hardware Subsystems

Dichroic Pickoffs

We have provided 3 sets of pickoff optics for use with CHAMP (the angle-of-incidence is 3 degrees). Each is designed with a 30' wedge and have been oriented with thick part down (i.e., transmitted beams is bent downward by 13.7', which may be relevant for downstream combiners during alignment procedure). All substrates have a broadband AR coating on the back-surface and the reflected light comes primarily from the front surface.

  * Short-wave Pass (SWP): 

These IR-grade Fused Silica substrates are coated with a dichroic coating to reflect K' band (2-2.3 microns) and to transmit JH bands (1.1-1.8 microns).

• Media:omega_swp.pdf: Performance of Shortwave Pass Dichroic (Omega)

%BR%

  * Long-wave Pass (LWP):

These Calcium Fluoride substrates are coated with a dichroic coating to reflect JH bands (1.1-1.8 microns) and to transmit K' band (2-2.3 microns and longer for possible future experiments).

• Media:lwp_performance_001.pdf: Performance of Longwave Pass Dichroic (Omega)

%BR%

  * Pickoffs Beam-splitters (BS):

These Calcium Fluoride beamsplitters were rejected from American Torch due to the coating not meeting specifications and the performance curves being proven unreliable. We believe the the coatings are about 50/50 at HK bands but are more like 75/25 (mostly transmitting) at J and beyond K band. This might prove useful in the future, but we do not expect these pickoff optics to be the best choice for most observers. Here is a measured transmission curve from the company, although we have not verified the accuracy yet:

• Media:Torch_BS_performance.pdf: Performance for (rejected) Beamsplitter Coatings (American Torch)

%BR%

Piezo Scanners

Piezojena 8micron Hardware card from National Instruments

Beamsplitters

The IR-grade Fused silica beamsplitters are 50% +/- 10% over the full JHK' bandpasses. The coatings were done by Omega Optical and you can find the coating performance here. The angle of incidence is ~11.5 degrees.

• Media:omega_bs.pdf: Beamsplitter Performance (Omega)

%BR%

Software

Real-time system (notes from Ettore 2010May)

Click here for detail on the upgrade to the realtime system RT_System

Interface Computer (wolverine)

Generating OPD Map

JDM: 2011Jan30

1. Acquire internal fringes using the Retro Cube A/B. See wiki page XXXX for table of pickoff mirror positions and Newport ESPGTK positions for easily acquiring fringes.

2. Take ~5 datasets (10 seconds each) of fringe data, ideally with slightly different phase offsets. As of 2011Jan30, we are using the kludge nsave=10000 which outputs a binary file called ~champdev/control/CHAMP/User/ftdata_#######.dat . This will get standardized using a fits format soon.

3. Copy datasets to wolverine for analysis: user: ~observe/CHAMP/Opdmap/Ftdata_DATE

4. run idl in ~observe/CHAMP/Opdmap

IDL> .r ftdata2idlvar.script

choose your FTDATA_DATE directory using dialog box [click on right-hand side of panel] and wait for it to finish. This may take a long while if one has recorded long sets of data. Will be much faster as FITS files.

IDL> .r opdmap_solver.script

Choose the ftdata*dat.idlvar file

the program wills how you fringes from 6 combiners. choose the one with fringes!

[Not working yet: JDM]

Appendices

Diagrams

targets filter box diagram filterwheel key

Spares

Optics

• Two (2) fused silica beam splitters for CHAMP combiner

• One (1) fused silica short-wave pass (SWP) dichroic pickoff

• One (1) calcium fluoride long-wave page (LWP) dichroic pickoff

• One (1) elliptical mirror mounted to invar piezo mount

• Four (4) f=450mm spherical mirrors for Tower of Power

• One (1) image slicer T1

• One (1) image slicer T2

• One (1) image slicer B1 [note: we are using the spare. the original B1 has some coating problems near apex and is put back as a backup/spare

• One (1) image slicer B2 [note: the backup spare B2 has slight problem where the bottom-right quad, B2d, is too large in one dimension. This means the pyramid will not fit in the holder. If one needs to use this backup, one will need to mill-out extra clearance in the holder]

Other things: TBDocumented, some card for camera electronics. zabar motors.

• One (1) motherboard for servers (compatible with mirkwood, champ -- one kept at CHARA, one at UM)

-- Main.monnier - 08 Feb 2009