GISAXS @ D-line: Data

Q: Where are my data ?

Each D-line user gets a user directory assigned on /home/specuser/USER, where USER corresponds to the name of the PI of the experiment. USER has the following default subdirectories:

data
corr
dark

The data directory contains the SPEC output files. These are all line-up and reflectivity scans, all appended to one file FILENAME, the name of which is declared in the newfile command. This file contains other important information, such as all motor positions at the beginning of each scan or CCD exposure (which corresponds to a tseries scan in SPEC) and the count rates of all monitor detectors along the beamline. The log file is in ASCII and can be read by any decent text editor, e.g. "gedit", "emacs", or "vi" (LINUX) or "notepad++" and "MS Word" (Windows).

The corr and dark directories contain all your images, the automatically corrected ones in corr, the dark images in dark. Data format is TIFF.

The /home/specuser/images directory contains all raw data files that the CCD collects. At the end of a user experiment ~/images can be copied to USER/raw, if users would like to keep the raw images:

cd ~/images
mv *.tif ~/[user]/raw

Otherwise, raw images will be removed to make space for the next user group. According to new NSF guidelines on scientific ethics, old data files need to be stored at CHESS. At present the archiving procedure is not yet defined; for the time being corrected files and log files are being kept on the acquisition computer and the analysis PC.

Q: How do I take my data home ?

The following procedure has proven to be solid:

when you come to CHESS make sure to bring a flash drive (8G) or an external hard disk (USB)
go to the CHESS User Computer Room and mount your drive using the USB extension ports
use the "ssh Secure File Transfer" program to directly copy the data to your disk

Alternatively you can copy to the hard disk of you laptop - there are plenty of high-speed ethernet connections in the Computer Room and there is a local wireless network. Using the letter you can directly mount the hard disk of the acquisition computer.

Because of the large amount of data produced by the area detector, I discourage the use of the CD or DVD burners.

DO NOT try to hook up external storage devices to the beamline computer - it is too easy to crash LINUX this way and make a huge mess.
Access to CHESS beamline computers from the outside has been disabled.

Q: How do I set up a lap top at D-line ?

The easiest and most reliable way is to connect the lap top to an ethernet connector (there are 2 user ports at the desk top and 1 at the prep table) and choose "find address automatically". No special password is required. Please do not hook up lap tops to the ethernet switch connecting the beamline computer and the CCD computer.

The Wilson Lab wireless network requires a password. Please contact the CHESS Operator for assistance. Despite the metal hutch walls, the wireless works reasonable in the beamline control area.