Differences between revisions 16 and 26 (spanning 10 versions)

Cleaning of the suspended test mass (Dec 2009)

Motivation

The round trip loss in the 40m cavity is estimated to be around 170ppm. We are going to confirm whether this comes from the hydrocarbon contamination and wiping of the mirror by acetone and isopropyl may result in improvement of the optical loss, or not.

In addition we can evaluate the use of those solvents. If we observe the degradation of the loss or the finesse, we will forbid them.

Measurements before the cleaning

- Visibility measurement

Most recent arm visibility measurement has been done on Oct 07, 2009. [http://nodus.ligo.caltech.edu:8080/40m/2070 corresponding elog entry]

Measured arm reflectivity R_cav:
X arm: 0.875 +/- 0.005
Y arm: 0.869 +/- 0.006

- Cavity pole measurement

Most recent arm visibility measurement has been done on Nov 10, 2009. [http://nodus.ligo.caltech.edu:8080/40m/2226 corresponding elog entry]

Measured arm cavity pole frequency f_pole [Hz]:
X arm: 1720 +/- 70
Y arm: 1650 +/- 70

- Estimated finesse and arm loss

Measurements after the cleaning

- Visibility measurement

- Cavity pole measurement

- Estimated finesse

Overview of the plan

We plan for the vent from 7th Dec to 11th Dec in 2009.
Preparation
- Wiping Preparation
- Vent Preparation
Monday:
- Pre-vent check 8:00~
- Vent from 9:30~
- Stop venting ~14:00
- Check OSEM/Oplev values
- Wipe ETMX 14:00~
  - Open ETMX 14:00~15:00
  - Mirror wiping 15:00~16:00
  - Check alignment / Close up 16:00~17:00
Tuesday:
- (ETMX wipe)
- ETMY wipe
- ITMY wipe
- Check of the optics in the chambers (ITMY)
~ Wednessday:
- ITMX wipe
  - Record ITMX position (pushing screws)
  - ITMX BB leveling
  - measure the distance of the breadboards
- 40m meeting
- Check of the optics in the chambers (ITMX/BS)
Thursday:
- Evacuation
Friday:
- Reserve

Detailed plan

~Friday, 4 Dec:
- Wiping preparation
  - Chemicals:
    - Small bottles (like 250ml) / 3 bottles each (no matter how the size is)
    - Acetone Spectral Grade, dehydrated (if possible)
    - Isopropyl alcohol Spectral Grade, dehydrated (if possible)
  - glass sylinges with metal needles, 50ul, at least three sets
  - mirror wiping paper, usual lens paper from Kodak or whatever
  - tools (well cleaned)
  - clamps to mark the position of ITMX: 3pcs
  - halogen light or whatever: light during the work
Vent Preparation
- Prepare the air cylinders (x6)
- Clean clean-tools again
- Alignment
  - Recenter: IPANG/POS, oplevs with the mirrors fully aligned [DONE]
  - Align the aux beam as a reference [DONE]
  - Update snapshots of all MEDM screens for OSEMs/OPLEVs/QPDs/PZT&strain gauges [DONE]
- Move extraneous equipment around chamber doors: Make sure we have clear access (esp. seismometers need moving) [DONE]
Monday:
- Check before the vent
  - Before venting, check that all the recentering done on Friday is still good. If not, redo. [DONE]
  - Turn off all OPLEV damping [DONE]
  - Turn on the shutter for the PSL beam. Put a manual block so that any failure can put the beam into the vacuum system [DONE]
  - Turn off all HV in vacuum (Input/Output PZT) [DONE]
  - Check the jam nuts of the bellows on the vacuum system (Two at the vertex, one at the MC tube) [DONE]
- Vent
  - Operate the valves according to the operation manual
    - Isolate the main vacuum manifold [DONE]
    - Introduce N2 up to 25torr [DONE]
    - Change the N2 cylinder to the instrument grade air. We need 6 cylinders to fill up the tank.
- During the vent - Door opening preparation
  - Test drive crane drives
  - Move and store abs. length setup to a safe place [DONE]
  - Practice drag wiping a spare random optic (with an arbitrary 2" CVI optic)
  - Practice cutting viton, so we can get the correct sizes if we need to replace stops. (Jenne)
  - Cut some viton tips for spare earthquake stop screws
- Environment
  - Keep eyes on particle counter: abort over 10,000
  - Look that we have good RGA scan
- Open ETMX
  - Take photos of ETMX before touching
- ETMX wipe
- Close up ETMX with light doors for the night
Tuesday:
Wednesday:
Thursday:
Friday:

-  ⇤ ← Revision 16 as of 2009-12-07 05:55:53 → 
  Size: 3921
  Editor: KojiArai
  Comment:
+   ← Revision 26 as of 2009-12-07 17:45:30 → ⇥
  Size: 4635
  Editor: KojiArai
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
-The round trip loss in the 40m cavity is estimated to be around 160ppm. We are going to confirm wether this comes from the hydrocarbon contamination and wiping of the mirror by acetone and isopropy may result in improvement of the optical loss, or not.
+The round trip loss in the 40m cavity is estimated to be around 170ppm. We are going to confirm whether this comes from the hydrocarbon contamination and wiping of the mirror by acetone and isopropyl may result in improvement of the optical loss, or not.
 Line 5:
-In addition we cna evaluate the use of those solvents. If we observe the degradation of the loss or the finesse, we will forbid them.
+In addition we can evaluate the use of those solvents. If we observe the degradation of the loss or the finesse, we will forbid them.
 Line 26:
-=== - Estimated finesse ===
+=== - Estimated finesse and arm loss ===
 Line 30:
-Line 32:
+Line 31:
-Line 34:
+Line 32:
-Line 36:
+Line 33:
-Line 41:
+Line 37:
-  * '''Wiping Preparation'''
  * '''Vent Preparation'''
+  * Wiping Preparation
  * Vent Preparation
-Line 45:
+Line 41:
-  * Prevent check 8:00~
+  * Pre-vent check 8:00~
-Line 48:
+Line 44:
+  * Check OSEM/Oplev values
-Line 57:
+Line 54:
+  * Check of the optics in the chambers (ITMY)
-Line 59:
+Line 57:
-  * ITMX position (pushing screws)
  * ITMX BB leveling
  * measure the distance of the breadboards
  * check of the optics in the chambers
+  * ITMX wipe
   * Record ITMX position (pushing screws)
   * ITMX BB leveling
   * measure the distance of the breadboards
  * 40m meeting
  * Check of the optics in the chambers (ITMX/BS)
 Line 64:
  * '''Thursday:'''
 Line 68:
+  * Reserve
-Line 70:
+Line 71:
-Line 72:
+Line 74:
- * '''Wiping Preparation '''
  * Wiping preparation
  * Wiping practice

 * '''Vent Preparation '''
  * Clean clean-tools again
  * Cut some viton tips for spare earthquake stop screws
  * Alignment
   * Align the aux beam as a reference
   * All HV in vacuum off (Input/Output PZT)
   * Update snap shots: sus, strain gauges, IOO, OMC....etc (OMC has no strain gauges)
   * Recenter: IPANG/POS, oplevs with the mirrors fully aligned
  * Environment
   * Test drive crane drives
   * Keep eyes on particle counter: abort over 10,000
   * Look that we have good RGA scan

   * Chemicals: small bottles (like 250ml) / 3 bottles each (no matter how the size is), '''Acetone''' Spectral Grade, dehydrated (if possible), '''Isopropyl alcohol''' Spectral Grade, dehydrated (if possible)
+   * Chemicals: 
    * Small bottles (like 250ml) / 3 bottles each (no matter how the size is)
    * '''Acetone''' Spectral Grade, dehydrated (if possible)
    * '''Isopropyl alcohol''' Spectral Grade, dehydrated (if possible)
-Line 96:
+Line 84:
- * '''Friday, 4 Dec: '''
  * Practice cutting viton, so we can get the correct sizes if we need to replace stops. (Jenne)
  * Recenter all of our pointing PDs (oplevs and IP_POS, IP_ANG).  (DONE 10pm Friday)
  * Update snapshots of all MEDM screens that have alignment information.  (DONE 10pm Friday)
  * Move extraneous equipment around chamber doors: Make sure we have clear access (esp. seismometers need moving)  (DONE 5pm Friday)
+ * '''Vent Preparation '''

  * Prepare the air cylinders (x6)
  * Clean clean-tools again
  * Alignment
   * Recenter: IPANG/POS, oplevs with the mirrors fully aligned '''[DONE]'''
   * Align the aux beam as a reference '''[DONE]'''
   * Update snapshots of all MEDM screens for OSEMs/OPLEVs/QPDs/PZT&strain gauges '''[DONE]'''
  * Move extraneous equipment around chamber doors: Make sure we have clear access (esp. seismometers need moving) '''[DONE]'''
-Line 103:
+Line 95:
-  * Before venting, check that all the recentering done on Friday is still good.  If not, redo.
  * Vent
  * During vent, practice drag wiping a spare random optic (maybe a 2" CVI optic?)
+  * '''Check before the vent'''
   * Before venting, check that all the recentering done on Friday is still good.  If not, redo. '''[DONE]'''
   * Turn off all OPLEV damping '''[DONE]'''
   * Turn on the shutter for the PSL beam. Put a manual block so that any failure can put the beam into the vacuum system '''[DONE]'''
   * Turn off all HV in vacuum (Input/Output PZT) '''[DONE]'''
   * Check the jam nuts of the bellows on the vacuum system (Two at the vertex, one at the MC tube) '''[DONE]'''

  * '''Vent'''
   * Operate the valves according to the operation manual
    * Isolate the main vacuum manifold '''[DONE]'''
    * Introduce N2 up to 25torr '''[DONE]'''
    * Change the N2 cylinder to the instrument grade air. We need 6 cylinders to fill up the tank.
 
  * During the vent - Door opening preparation 
   * Test drive crane drives
   * Move and store abs. length setup to a safe place '''[DONE]'''
   * Practice drag wiping a spare random optic (with an arbitrary 2" CVI optic)
   * Practice cutting viton, so we can get the correct sizes if we need to replace stops. (Jenne)
   * Cut some viton tips for spare earthquake stop screws

  * Environment
   * Keep eyes on particle counter: abort over 10,000
   * Look that we have good RGA scan
-Line 107:
+Line 120:
-  * Take photos of ETMX before touching
+   * Take photos of ETMX before touching

  * '''ETMX wipe'''