PRM, SRM and the ENDs are kicking up.  Computers are down.  PMC slider is stuck at low voltage.

Diego Bersanetti received 40m specific safety training today.

ETMX sus damping restored and PMC locked manually.

 X-arm  AP Armaflex tube insulation is cable tightened into cable tray. Only turning 6 ft sections are taped together.

Remaining things to do: install ends protection tubing

 Katherine Dooley has received 40m specific basic safety training in the 40m lab

The first real rain of this year finds only one leak at the 40m

 EricQ and Steve,

Steve preset the vacuum for safe-reboot mode with C1vac1 and C1vac2 running normal: closed valves as shown, stopped Maglev & disconnected valves V1 plus valves with moving labels.

(The position indicator of the valves changes to " moving " when its cable disconnected )

Eric shut down Chiara, installed APC's UPS Pro 1000 and restarted it.

All went well. Nothing unexpected happened. So we can conclude that the vacuum system with running C1vac1 and C1vac2 is not effected by Chiara's losing AC power.

 TP3 dry pump  replaced at 540 mT as TP3 50K_rpm 0.3A with annulos load. It's top seal life time was 11,252 hrs

We run out of N2 for the vacuum system. The pressure peaked at 1.3 mTorr with MC locked. V1 did not closed because the N2 pressure sensor failed.

We are back to vac normal. I will be here tomorrow to check on things.

 ITMX damping restored.

All suspensions were tripped. Damping were restored. No obvious sign of damage. BS OSEM-UR may be sticking ?

C1:SUS-ETMX_QPD is removed and internal SM1 thread adapter epoxied into position as it is at the Y end

This adapter will take FL1064-10 line filter holder

Line filter is attached and qpd needs alignment.

Missing filter found. Labeled drawer OPHIR in control room - behind soldering station-  with spare battery and filter

100 and 10 days trends of ETMX and ETMY_SUSPIT.  One can see clearly the earthquaks of Dec.30 and 31 on the 10 day plot. You can not see the two shakes  M3.0 & M4.3 of Jan. 3 

The long term plot looks OK , but   the 10 day plot show the problem of ETMX as it was shaken 4 times.

Yesterday morning was dusty. I wonder why?

The PRM sus damping was restored this morning.

ETMX YAW stopped drifting Jan 8, 2015

Aluminum support beam removed and seismometer is covered.

Yesterday afternoon at 4 the dust count peaked 70,000 counts

Manasa's alergy was bad at the X-end yesterday. What is going on?

There was no wind and CES neighbors did not do anything.

Baja 4.9 m earth quake tripped suspentions, except ETMX Sus damping recovered. MC is locking.
 

Safety audit went soothly. We thank all participients.

Correction list:

1, Bathroom water heater cable to be stress releived and connector replaced by twister lock type.

2, Floor cable bridge at the vacuum rack to be replaced. It is cracked.

3, Sprinkler head to be moved eastward 2 ft in room 101

4, Annual crane inspection is scheduled for 8am Marc 3, 2015

5, Annual safety glasses cleaning and transmission measurement will get done tomorrow morning.

Safety glasses were measured and they are all good. I'd like to measure your personal glass if it is not on this picture.

The temperature of the east and south ends  are normal, they are about the same.

Konecranes' Fred inspected and load tested all tree cranes at with 450 lbs

The BS oplev servo was kicking up the BS. It was turned off

Green glass for aLIGO OMC shield is temporarly stored in the inside of the Y-arm.

Polaris mounts ordered.

Are the two  visible small srews holding the adapter plate only?

If yes, it is the weakest point of the IOO path.

We run out of N2 for the vacuum system 6 hrs ago. The pressure rose to 1.2 mTorr with V1 closed. The interlock worked! See Nirogen presure reading fixed at http://nodus.ligo.caltech.edu:8080/40m/10968

The vacuum interlock: Nitrogen pressure transducer is reading the pneumatic pressure continously at the pump spool and c1vac1 processing it. When it drops below 60 PSI it closes V1 gate valve and V4 & V5.  Gate valve V1 needs minimum 60 PSI to close. It is critical that V1 is closed before you run out of Nitrogen so the IFO pressure is contained.

IFO vacuum is back to Vac Normal. The MC is locked.

cc4 = 2E-6 Torr with VM1 open.

Daily N2 consumption measured to be 530PSI as 3 days on 3-27-2015 but note: it does vary !

I have seen it as high as 900 psi  The long term average ~750 psi

To achive the same beam height each components needs their specific post height.

We have 2.625" tall, 3/4" OD SS posts for Polaris K1 mirror mounts: 20 pieces

Ordered Newport LH-1 lens mounts with axis height 1.0

  I turned on the HEPA at the south end during the LSC. Sorry I ment to turn it off.

The PMC is seated on 3 SS balls and it is free to move. I'm sure it will move in an earthquake. Not much, because the input and output K1 mirror frame will act as an earthquake stop.Atm2

Are there a touch of super glue on the balls? No, but there are V grooves at the bottom and on the top of each ball.Atm3

The 40m fenced area will start storing this large ~ 8000 lbs chamber on April 14. The asphalt will be cut, jack hammered the next 2-3 days in order to lay concrete.

Their schedule is from 8 to 5 starting tomorrow.  We are asking them to work from 6 to 3pm

ETMX is about 12-15 ft away

ITMX, ETMY, BS and SRM are oscillating ?

I saw this kicking before  

Jackhammering was happening around 7:30am

It looks like it did no harm. It is too early to say what may have moved. Rana's worrisome  email was late.

The ground preparation is completed.

There was a period of short unexpected jackhammering this morning. I asked them to stop.

The good mood of GTRX was not changed.

It is here.

The IFO_overview of oplevs seems ok, The servos are working fine. The green arms are locked, but master and oplev_summary monitoring screens are not.

I'm proposing to Erick G. to postpone the oplev noise measurement.

Manasa and Steve,

Is this what you want?  Dashed lines are dark.

BS and PRM oplevs are blocked for this measurement. I will restore to normal operation at 4pm today.
 

BS & PRM oplev is restored. Note: the F -150 lens was removed right after the first turning mirror from the laser. This helped Rana to get small spot on the qpd.

It also means that the oplev paths are somewhat different now.

ETMX sus damping restored.

RFpds box is moved from RF cabinet E4 to clean cabinet S15

Inventory updated at https://wiki-40m.ligo.caltech.edu/RF_Pd_Inventory

Large Area InGaAs PIN Photodiode -- C30642GH      6 pieces in stock

Large Area InGaAs PIN Photodiode with a 2,0 mm active diameter chip in TO-5 package with flat glass window

Large area InGaAs PIN photodiode with useful diameter of 2,0 mm in a T0-5 package with a flat glass window. The C30642GH provides high quantum efficiency from 800nm to 1700nm. It features high responsivity, high shunt resistance, low dark current, low capacitance for fast response time and uniformity within 2% across the detector active area.

Few 1/4 -20 socket cap head screw with washers were tested for optimum torque.

QJR 117E Snap On  torque wrench was used. I found that 40 lb in was enough.

Looked up recommended values on the web later:

Our Thorlab SS 1/4-20 screw kits are SS 18-8 as DRY 70 inch / lbs max, lubricated  60 inch / lbs max

These numbers will varie with washers, material it's going into and so on!

BLACK-OXIDE Alloy Steel Socket Head Cap Screws can go much higher value

Thread Size	1/4"-20
Length	1/4"
Thread Length	Full
Additional Specifications	Black-Oxide Alloy Steel
RoHS	Compliant

The standard among high-strength fasteners, these screws are stronger than Grade 8 steel screws. They have a minimum tensile strength of 170,000 psi. and a minimum Rockwell hardness of C37. Length is measured from under the head.

Inch screws have a Class 3A thread fit. They meet ASTM A574.

Black Oxide—Screws have been heat-treated for hardness, which results in a dark surface color.

 

The information in this 3-D model is provided for reference only. Details

 

 

 

We still do not know that what torque values we get best performance : minimum jiggel and drift etc.

After looking at these numbers I raise my recommendation to 50 inch / lbs on a std aplication.

Rana is next to calibrate his feelings and declare the right number.

Than Koji....and so on

Once we a number, than I buy more torque wrenches to fit it.

Air cond filters checked by Chris. The 400 days plot show 3 bad peaks at 1-20, 2-5 & 2-19

This watch script gives little time to replace N2 cylinder. When the regulated supply drops below 60 psi the cylinder pressure is 60 psi too.

It is more of a statement that V1 is closed and act accordingly. It's only practical if you are in the lab.

Rana pointed it out correctly that we need this message 24 hrs before it happens. This requires monitoring  of total supplies , not the regulated one.

So we need pressure transducers on each nitrogen cylinder, before the regulator. The sum of the two N2 cylinder when they are full 4000 - 4500 psi

The first email should be send out at 1000 psi as sum of the two cylinders. This means that you have  1 day to replace nitrogen cylinder.

 Most of the time the daily consumption is 750 +-50 psi   

However sometimes  this variation goes up   ~750 +-150 psi