= 20180222 =
 * [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=4259]]
 * [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=4265]]


== Today's activities ==
Workers: Simon, Miyo, Akutsu
 * (The WAB was locked yesterday.)
 * Attached a reflector to the WAB -Y side, and the counter mass (the same shape as the reflector) +Y side.
 * Installed three photosensors; positions were at +X, -Y, and the bottom, and they faced -X, +Y, and +Z, respectively, to look at the reflector.
  * The distance from the sensor head to the reflector are each 17mm; see [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=4265|here]].
  * Due to the 50-mm pitch of the M6 screw holes on the optical table in the chamber, it was impossible to install the photosensor supports to the positions we like to put; so far a breadboard with 25-mm pitch M6 screw holes was inserted, and this will be replaced to a vacuum compatible one later.
  * Connected the pins.
 * Attached a set of SmCo magnets for a coil-mag actuator; the magnets were attached at -X,-Y, about 45-deg clockwise from the bottom.
 * Installed a coil magnet actuator in -X direction.
  * Before the installation, the coil's pins were connected to electric wires with copper pipes; because the net diameter of each pin was thicker than that of photosensor, new pipe (phi 1.2mm) was bought and adopted.
  * Connected the pins of the coil to U and V of P23.
  * The coil's resistance was measured as 13 ohm, while the resistance measured at the distributor was 75+75+13 = around 163 ohm due to the one-way 75 ohm electric wires.
 * Unlocked the suspension; The WAB is now floating.
 * Tried to exert a force by the coil-magnet actuator, but failed. This would be due to the too large total resistance so the current flow was not enough.
  * Should we use the other pins of 4-ohms, which are reserved for a thermometer???
 * '''[Ongoing]''' Need cares of water springs from anchor bolts for oplev pylons.
 * '''[Ongoing]''' Need to confirm what are the scratch lines made by the measurement by the KEK team last week.

== Next plan ==
 * Change the pin assign so that enough current can flow to the coil.
 * Add capacitors to the transimpedances in the OSEM satellite box.
 * Complete the calibration of the oplev; the arm length was reported by Simon, so....
 * Check the balance of the suspended WAB with some wires and sensors are attached.
 * Check how the damping would be now after the replacement of the damping magnets.
 * Check the reproducibility of the alignment of the suspension among several modes.  
 * Check heights of several points.
 * Take care of water spring??

== Wanted! ==
 * Two burndy connectors, vacuum compatible.
 * '''''Stages outside the chamber''''' to ease wiping our legs.
 * Good '''''rail(?)''''' to move the WAB suspension in the cryostat in the main beam direction.
 * '''''Chain block?''''' to support the load in the chamber.
 * A clock to know the time easily.
 * M6 screw set.