Bigelow 2MASS User Notes

This wiki is intended to describe observations with the 2MASS camera on the Mount Bigelow Kuiper Telescope.

Observer's Guide from UVa. February 2011

Focus: 9667 on February 12, 2011

Typical Exposure time: 10 s for faint objects.

Program: astrocam_dev

This allows the user to take 4 images in each jog position. Improves efficiency.

machine: big2mass.as.arizona.edu

user: observer

Twilight flats can be taken about 30-40 minutes before sunrise. Use 1 s exposure. Take until K band is above 20-30,000.

Data: /home/observer/Hinzgroup/110212 (on Feb. 12, 2011)

Transferring files to zero:

If the data is saved using the directory convention above, you can run

transfer-files.sh

at a command prompt. This will periodically check for new data and back it up onto zero in Tucson.

Note: you may need to first create the destination folder on zero if it doesn't already exist

2MASS camera Contacts:

Meredith: mmd9n@virginia.edu

Mike Skrutskie:

Approximate Star Centers:

K: 122, 671

H: 120, 412

J: 118, 159

Filling the Dewar:

1. make sure the yellow rubber hose is plugged into the side of the dewar. there are two ports coming out of the dewar, one on the bottom and one on the side coming out diagonally. the rubber hose should be permanently plugged into the diagonal port (see below).

2. raise the platform, with the LN canister on it.

3. remove the white clip on the the rubber hose

4. plug the other end of the rubber hose into the metal protrusion on the dewar (see below).

5. turn the screw on the top of the dewar (or turn the switch if it's a switch) so that the LN flows. look at the pressure gauge. if the pressure is < 5 psi, proceed to step 6. otherwise, the dewar is filled when LIQUID starts flowing out of the vertical port on the dewar. when the dewar is not full, it will normally emit gas when it's being filled.

6. take the really long (> 10 feet) clear plastic hose that is plugged into the wall by the room entrance and plug it into the little opening under/near the pressure gauge. there is a nob/switch associated with this port. open the switch so that gas can flow into the canister. go over to the wall and turn the handle in the horizontal direction so that gas flows through the clear plastic tube and into the LN canister. this will cause the pressure to increase. you can adjust the angle of the lever by the wall and/or the switch on the canister to keep the pressure ~ 5-6 psi. when liquid is flowing out of the dewar, it's full.

7. close all the nobs. wait for the yellow rubber hose to warm up, then unplug it from the canister, and put the white clip back on so that the hose is bent through it to prevent further flow.

Troubleshooting:

Problem-you see abnormally high K band flux, but J and H are normal-->this probably means the dome is in the way of the telescope.

Solution-you need to re-initialize the dome. turn off auto dome. there is a black arrow drawn on the dome pointing downwards, at the shutter opening. similarly, there is an upward facing arrow directly due east. rotate the dome until they are pointing at each other. then go to "declare" in the TCS software and select dome initial or initial dome. after that, turn on auto dome and it should work.

Problem-your telescope pointing is off (ie, bright star not found in 2mass FOV).

Solution-first make sure the telescope stows properly. stow the telescope using the TCS software. in the telescope chamber, at the yellow base of the telescope, there is a dial/viewer with some numbers on it. there is a yellow drawn line. move the telescope E/W until the yellow line matches up with the "0". you're not done yet...now go over to the N/S dial on the telescope. it's a big black thing with angles written all over it. the "0" should be pointed right at 32.25. if it's not, adjust the telescope in the N/S direction until it is. Next, exit the TCS software completely. Re-open the TCS software. when you do this, TCS thinks you're at zenith (stow). now check your pointing by going to a very bright star with the TCS software (brighter than 2 mags). there are a few view-finders/eyepieces on the side of the telescope. choose one and open its mirror cover by pulling down on the white nob lever. you should easily hear the mirror cover opening. use the 4 small buttons on the controls next to the eyepiece to adjust the FOV until the bright star is in the center. after this, go to the TCS software, go to "declare", and select "next init" or "init next". check your pointing by moving to another bright star to see if it's in the view finder center. that's it!