Differences between revisions 9 and 16 (spanning 7 versions)

Cleaning of the suspended test mass (Dec 2009)

Motivation

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.

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.

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

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:
- Prevent check 8:00~
- Vent from 9:30~
- Stop venting ~14:00
- 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
~ Wednessday:
- ITMX position (pushing screws)
- ITMX BB leveling
- measure the distance of the breadboards
- check of the optics in the chambers
Thursday:
- Evacuation
Friday:

Detailed plan

~Friday, 4 Dec:
- Wiping preparation
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)
  - 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
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)
Monday:
- 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?)
- Open ETMX
- Take photos of ETMX before touching
- Close up ETMX with light doors for the night
Tuesday:
Wednesday:
Thursday:
Friday:

-  ⇤ ← Revision 9 as of 2009-12-04 20:35:37 → 
  Size: 2073
  Editor: JenneDriggers
  Comment:
+   ← Revision 16 as of 2009-12-07 05:55:53 → ⇥
  Size: 3921
  Editor: KojiArai
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
-Whether contamination or not
+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.
 Line 5:
-== Measurements before the vent ==
+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.

== Measurements before the cleaning ==
-Line 7:
+Line 9:
-=== - Finesse 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 ===

== Measurements after the cleaning ==
=== - Visibility measurement ===

=== - Cavity pole measurement ===

=== - Estimated finesse ===

-------
-Line 12:
+Line 41:
-  * wiping preparation
  * wiping practice
  * aux beam as a reference....align to overlap in vacuum
  * Input PZT (strain gauge) /HV off/OMC PZT HV
    * update snap shots: sus, strain gauges,IOO, OMC....etc (OMC has no strain gauges)
    * recenter: IP-ANG-POS, oplevs..... at full lock
  * test drive crane drives
  * clean clean-tools again
  * keep eyes on particle counter: abort over 10,000
  * cut some viton tips for spare earthquake stop screws
+  * '''Wiping Preparation'''
  * '''Vent Preparation'''
-Line 24:
+Line 45:
-  * Vent / Open ETMX if possible
  * Take pictures before touching
  * Record positions of the mirrors (OSEMs/OPLEVs)
+  * Prevent check 8:00~
  * Vent from 9:30~
  * Stop venting ~14:00
  * Wipe ETMX 14:00~
   * Open ETMX 14:00~15:00
   * Mirror wiping 15:00~16:00
   * Check alignment / Close up 16:00~17:00
-Line 29:
+Line 54:
-  * ETMX wipe
+  * (ETMX wipe)
-Line 31:
+Line 56:
+  * ITMY wipe
-Line 33:
+Line 59:
-  * IPANG beam
-Line 38:
+Line 63:
-  * ITMY wipe
  * ITMX wipe
-Line 41:
+Line 64:
- * '''Thursday:''' - Evacuation
+ * '''Thursday:''' 
  * Evacuation
-Line 43:
+Line 67:
- * '''Friday:  '''
+ * '''Friday:'''
-Line 46:
+Line 70:
+ * '''~Friday, 4 Dec: '''
  * Wiping preparation
 * '''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)
   * 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
-Line 49:
+Line 98:
-  * Recenter all of our pointing PDs (oplevs and IP_POS, IP_ANG).
  * Update snapshots of all MEDM screens that have alignment information.
  * Move extraneous equipment around chamber doors: Make sure we have clear access (esp. seismometers need moving)
+  * 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)
-Line 56:
+Line 105:
   * During vent, practice drag wiping a spare random optic (maybe a 2" CVI optic?)