Differences between revisions 7 and 29 (spanning 22 versions)

Arm Length Stabilization System

Wiki for ALS (Arm Length Stabilization; Auxiliary Lock System), a.k.a green lock system

ALS Configuration

JGW-T1807771

To Do

optical layout of PR2/SR2 chambers, POP/POS table
select AOM and AOM driver
fix green fiber specs, including how to do the laying
fiber collimators for green
green fiber after EOM/AOM or before EOM/AOM
- Not much difference from noise, cable length point of view.
- Alignment jitter noise from AOM will be less if fiber comes after AOM. So, let it so.
fiber for PLL beat or not
where to put frequency offset: PLL or arm length
more detailed noisebudget
initial alignment planning
comm/diff servo topology
- necessity of summing node for common mode servo (LIGO-D1300782)
  - first, try with digital switch and decide
lock acquisition scheme

List of Items

Electronics

Common Mode Servo Board JGW-D1503705 (ready)
PLL Board (similar to CMB, ordered to AEL)
Phase Frequency Discriminator LIGO-D1002476 (prototype developed at UToyama)
Fast version of IQ Demodulator LIGO-E1100044 (ordered to AEL)
RF Oscillator for PDH Keysight N5181B MXG (ready)
VCO for PLL Keysight E8663D (ready)
Frequency counter Tektronix FCA3103 (ready)

Opto-electronics

Broadband PD for PLL Newport 818-BB-21A (1.2 GHz bandwidth)
Resonant PD for green PDH JGW-D1201280
AOM G&H 3080-125 (80MHz) and AOM driver G&H 1075FM-1 (1W, 5MHz BW). (ordered)
EOM: Qubig xxxxxx (ready)
- modulation frequencies are 32 MHz and 33 MHz JGW-T1605626
QPD for green beam pointing? (Use Oplev QPD?)
Picomotor mount? (ordered)

Optics

Faraday isolator Thorlabs IO-5-532-HP (to be ordered)
Periscopes Thorlabs Ø1.5inch Post Assembly (ready)
Dichroic mirror: LEO DRX-1064/532-45P-UF-2038 (ready)
Harmonic splitter: LEO LWP-45-R532-T1064-UF-2038 (ready)

Fiber optics

Fiber (under test at UToyama)
- probably with jacket, with endcap, without AR coating
- polarization maintaining
Fiber collimator (Tholabs PAF? Thorlabs triplet lens collimator?)

Drawings

PSL table JGW-D1706335, JGW-G1707060
Fiber layout JGW-G1707060
POP table
PR2 in-vac JGW-G1706473
TRX
POS table
SR2 in-vac
TRY

Conceptual

ALS configuration JGW-T1605353 (see Candidate4)
Optical layout around PRs JGW-T1605261
Optical layout around SRs JGW-T1605967
Green beam positions JGW-T1807775

Noisebudget

https://granite.phys.s.u-tokyo.ac.jp/svn/LCGT/trunk/kagranoisebudget/GreenLock

Documents

Document tree for ALS JGW-E1807769

-  ⇤ ← Revision 7 as of 2018-02-02 16:17:50 → 
  Size: 2673
  Editor: YutaMichimura
  Comment:
+   ← Revision 29 as of 2018-03-12 10:41:38 → ⇥
  Size: 4533
  Editor: YutaMichimura
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 2:
+ Wiki for ALS (Arm Length Stabilization; Auxiliary Lock System), a.k.a green lock system
-Line 3:
+Line 4:
-== Configuration (One Arm) ==
{{https://gwdoc.icrr.u-tokyo.ac.jp/DocDB/0074/E1707416/001/DSC_0055.JPG|ALS Configuration|width=500}}
+{{https://gwdoc.icrr.u-tokyo.ac.jp/DocDB/0077/T1807771/002/ALSSchematic.png|ALS Configuration|width=500}}
 [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7771|JGW-T1807771]]
-Line 10:
+Line 11:
+ * fiber collimators for green
-Line 11:
+Line 13:
+  * Not much difference from noise, cable length point of view.
  * Alignment jitter noise from AOM will be less if fiber comes after AOM. So, let it so.
 * fiber for PLL beat or not
-Line 15:
+Line 20:
+  * necessity of summing node for common mode servo ([[https://dcc.ligo.org/LIGO-D1300782/public|LIGO-D1300782]])
   * first, try with digital switch and decide
-Line 25:
+Line 32:
- * Frequency counter (optional) [[https://www.keysight.com/ja/pd-1893411-pn-53220A/350-mhz-universal-frequency-counter-timer-12-digits-s-100-ps?cc=JP&lc=jpn|Keysight 53220A]]?
+ * Frequency counter [[https://www.tek.com/frequency-counter/fca3000-3100|Tektronix FCA3103]] (ready)
-Line 30:
+Line 37:
- * AOM and AOM driver (to be determined)
+ * AOM G&H 3080-125 (80MHz) and AOM driver G&H 1075FM-1 (1W, 5MHz BW). (ordered)
-Line 32:
+Line 39:
+  * modulation frequencies are 32 MHz and 33 MHz [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5626|JGW-T1605626]]
-Line 43:
+Line 51:
- * Fiber collimator (Tholabs PAF? Fixed focus collimator?)
+  * probably with jacket, with endcap, without AR coating
  * polarization maintaining
 * Fiber collimator (Tholabs PAF? [[https://www.thorlabs.co.jp/newgrouppage9.cfm?objectgroup_id=5124|Thorlabs triplet lens collimator]]?)
-Line 46:
+Line 56:
- * PSL table
+ * PSL table [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=6335|JGW-D1706335]], [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7060|JGW-G1707060]]
 * Fiber layout [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7060|JGW-G1707060]]
-Line 48:
+Line 59:
- * PR2 in-vac
+ * PR2 in-vac [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=6473|JGW-G1706473]]
-Line 53:
+Line 64:
+=== Conceptual ===
 * ALS configuration [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5353|JGW-T1605353]] (see Candidate4)
 * Optical layout around PRs [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5261|JGW-T1605261]]
 * Optical layout around SRs [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5967|JGW-T1605967]]
 * Green beam positions [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7775|JGW-T1807775]]

== Noisebudget ==
 * [[https://granite.phys.s.u-tokyo.ac.jp/svn/LCGT/trunk/kagranoisebudget/GreenLock]]