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PCTS Workshop Day 1 Recordings:

PCTS Workshop Day 1 Talks: Patrick Brady Peter Shawhan

PCTS Workshop Day 1 Discussion Panel:

Note: although all panel members are members of the [|LIGO Scientific Collaboration], the opinions expressed here are not necessarily those of the LSC. When possible, we link documents and policies by the LSC.



Questions:


 * **What is the status of LIGO/Virgo commissioning? (Duncan, Gaby)**
 * What is the status of LIGO commissioning? (Duncan, Gaby)
 * An overview of the aLIGO commissioning schedule is available on the aLIGO schedule page.
 * Next big milestone is locking one 4km arm at Hanford.
 * Will be followed by locking the Michelson at Livingston.
 * Everything is going well with install (some issues, but not unexpected and within contingency).
 * What is the LIGO time line (Duncan, Gaby).
 * 2012 Start integrated testing (one arm lock at LHO, corner Michelson at LLO)
 * 2013 L1 interferometer begins commissioning.
 * 2014 H1 interferometer begins commissioning.
 * 2015 All interferometers are accepted (and end of aLIGO project - operations and commissioning follows)
 * Note: accepted means that the IFOs can lock for ~ two hours
 * Commissioning will be needed to go beyond this to design sensitivity.
 * What is the status of Virgo commissioning? (Duncan, Gaby)
 * Virgo is ~ 1 year behind aLIGO, as they had an additional run (VSR4) while the aLIGO upgrades began. Plan to have V1 locking in 2015.


 * **What is the timeline for the first science run of the Advanced era? (Duncan, Gaby)**
 * Depends on schedule shown above.
 * Possible first LIGO science runs are scheduled for 2015.
 * These runs will involve H1 and L1 (assuming H2 is sent to India, which is looking more and more likely)
 * Runs in 2015 will not be at full design sensitivity.
 * Thermal effects make high laser power difficulty to control, so early runs will likely be at 25 W, rather than 125 W.
 * Commissioning at low frequencies is always hard, so initial runs likely to be less sensitive at low frequency.
 * **Note: it is very difficult to make predictions for the rate of progress for machines which are not yet familiar and not even fully installed yet!**
 * Previous experience may be our best guide, with some optimism for experience. See [[file:iLIGOStrainProgress.pdf]]


 * Open questions that the LSC is discussing. No conclusions, yet, so this is only a guide and **not a definitive statement of the collaboration.**(Duncan, Gaby)
 * We'll likely have several runs with of increasing duration and sensitivity, probably starting in 2015.
 * When does it make sense to have a first short science run? Perhaps some time in 2015+ we will have BNS range of 50 - 100 Mpc. Run of a couple of months?
 * When should we have first extended science runs? Sometime in 2016+ we will have BNS ranges 100 - 140 Mpc. Run of order six months?
 * When will we all the aLIGO detectors be at design sensitivity? Full zero-detune high-power will follow, and will take years. Guess for when this will be? 2018-19+ with BNS sensitivity 140-200 Mpc?
 * Virgo will be part of these as soon as available.
 * KAGRA plans to have a non-cryogenic detector with sensitivity similar to initial LIGO detectors by 2015, and reach increased sensitivity with cryogenic by 2018.


 * Noise curves for early aLIGO runs: **tentative and subject to caveats above!**(Duncan)
 * [[file:aLIGOPossible.pdf]]


 * Instrument sensitivity (Duncan):
 * aLIGO noise curves are posted in the LIGO DCC aLIGO Strain Sensitivity
 * Zero detune high-power is the "canonical" noise curve for full sensitivity.
 * [[file:AdVirgo-Design-VIR027A-09.pdf]]

(Samaya) early years of Ligo Hanford and Livingston: possibly >three incremental runs until design sensitivity is reached. A tentative starting date is @ the end of December 2014. i) lower laser power and no signal recycling ii) lower laser power and signal recycling iii) full laser power and signal recycling Noise curves should be shown and the improvement in sensitivity should be indicated at different frequency runs. Discussion of possible GW+EM science in the period 2015-17 using only two LIGO detectors (with no Virgo) is important.

(Samaya): Virgo: one year delay of advanced LIGO -- 2017-2018+ for three detectors.

(Samaya): Discussion of calibration.


 * **Beyond aLIGO/AdVirgo: Upgrades to existing facilities**

(Samaya) Discussion of optical squeezing and at what stage it will be implemented, and possible gains.

(Duncan, Gaby): currently instrumental teams are scoping out possible upgrades within the LIGO facilities. Some details in 2011 LSC instrumental [|white paper], more details will appear in 2012 white paper later this year.


 * **Third-generation detectors.**

(Samaya). A mention of tentative plans for the follow-on to advanced LIGO.

(Duncan, Gaby) Europeans have an Einstein Telecope design document available from []

(Duncan, Gaby) No major funded US effort right now, focus is on R&D components.


 * **What's the status of LIGO-India?**

(Gaby) The LIGO Lab has recommended NSF to approve LIGO-India; NSF and NSB are seriously considering this recommendation. If approved and everything goes well, a LIGO-India detector could join the Advanced Detectors network by ~2020 - see below.

(Samaya). What are the main challenges for LIGO India in terms of instrument construction? (Gaby) The instrument itself would be the LIGO H2 detector, so there shouldn't be any challenges that are not seen first with L1 and H1. The challenges are instead on the Observatory construction (including site selection and vacuum system), and commissioning. Commissioning should be helped by earlier experience with L1 and H1, but it's always a challenge.

Comparison of aLIGO USA and LIGO-India timelines (Duncan, (thanks to David Shoemaker)). **Subject to NSF and NSB approval!**


 * If we get approval, this is how we would proceed.**


 * = **aLIGO-USA** ||= **Planned LIGO-India** ||
 * Oct 2011: Installation start ||  ||
 * May 2012: Integrated test start ||  ||
 * Jul 2012: corner Michelson testing || Mid 2012: Project start ||
 * July 2013: All installation complete || Mid 2013: Contractors selected ||
 * Nov 2014: All interferometers accepted || Mid 2014: Start site development ||
 * 2015: Possible first observing run || 2015:Construction well underway ||
 * 2017: Higher sensitivity runs || 2017: Ship instrument to India ||
 * || 2018: Facility ready, start install ||
 * || 2019: installation complete ||
 * || Early 2020: interferometer accepted ||
 * || Mid 2020: First science run ||

(Samaya). How does LIGO-India help in sky reconstruction? (see Veitch et al. (2012) and Schutz (2011))


 * **What are the goals for science analysis in the Advanced detector era?**

These can be found in the 2011 Data Analysis [|white paper]. We'll perform searches we've done in S5/S6 (unmodeled transient sources, binary systems, rotating stars and stochastic background), but with more of the searches for transients using a low latency, sky localization and conservative but reliable and fast false alarm estimate to be able to produce alerts to EM/HE partners.


 * **With what latency and accuracy can positional and intrinsic information be provided, eg for EM followup? (Richard)**

(Samaya). Discussion of LSC parameter estimation group and low latency group pipelines. Latency of 45 mins (human limited) is S6 for initial sky reconstruction maps. Advanced LIGO: latency of ~10 minutes (?). Sky localization--be prepared for 1-100 (or 100s sq. deg for the first couple of years with Virgo running) sq. deg accuracies depending on whether the signal is threshold/: plethora of papers in recent years for burst/inspirals in advanced LIGO- Wen and Chen (2010), Fairhurst (2009,2010), Klimenko et al. (2010), Nissanke et al (2011), Veitch et al. (2012)





[|Toward Early-Warning Detection of Gravitational Waves from Compact Binary Coalescence]


 * **What are the plans for data release at the start of S7? after the first detection? (Gaby)**

(Gaby) LSC and Virgo are finalizing the approval of a policy shown here:.

(Gaby) The official LIGO/LSC policy for open data is found [|here].

(Gaby) LSC and Virgo are having conversations with KAGRA about a data-sharing agreement.

(Samaya). Public LIGO open data documents

[] []

(Samaya). some mention of Virgo/KAGRA etc's plans would be useful.