Program (Sunday, May/21)
  Chaired by W.T. Ni (NTHU)
09:00~09:20M. Ando (U.Tokyo) KAGRA observation scenario and roadmap (slides)
09:20~09:40R. Takahashi (NAOJ)
Installation status of vibration isolation systemInstallation of vibration isolation system is on going for bKAGRA. Type-A system, Type-B system, and Type-Bp system are installed to EY, BS, and PR3 respectively at beginning. Totally two Type-A systems, three Type-B systems, and three Type-Bp systems are used in the phase 1.
(slides)
09:40~10:00K. Hayama (ICRR) Detector characterization (slides)
10:00~10:20T. Tomaru (KEK)
KAGRA Cryogenic System Cryogenic mirror system is a feature in KAGRA gravitational wave detector under constructing in Kamioka, Japan. We have already installed four cryostats to install cryogenic system at the site, and cooling-down tests of three of four has been completed. A cryogenic mirror suspension system was assembled at the Y-end site and installed into cryostat as early test. Overview and present status of cryogenic system construction at the KAGRA site will be presented.
(slides)
10:20~10:35Break
  Chaired by T. Tomaru (KEK)
10:35~10:50K. Craig (ICRR)
Hydroxide Catalysis Bonding (HCB) of Sapphire mirrors In gravitational wave detectors, methods of jointing must have high strength and low noise, particularly if the joint is close to the mirror. In KAGRA, an additional problem is that the joints must also feature high thermal conductivity. For the purpose of joining the KAGRA mirrors to the ears used to connect the mirrors to the suspending fibers, hydroxide catalysis bonding shall be used. These bonds are extremely thin, with high strength and has been used to bond ears to a test mass of the same dimensions as the KAGRA test masses.
(slides)
10:50~11:05T. Ushiba (ICRR)
Control for the KAGRA cryogenic payload For KAGRA operation, several kinds of controls are necesarry such as initial allienment, damping control, and so on. Therefore, we are developing cryogenic sensors and actuators. I this talk, we report a progress on that.
(slides)
11:05~11:15T. Yamada (ICRR)
Evaluation of 6N Aluminium Heat-Link Abstract: The heat-link is the essential path to cool down the cryogenic payload system. We use 99.9999% (6N) aluminum of high purity for the heat-link from the points of view of high thermal conductivity and low young's modulus. We measured Residual Resistivity Ratio (RRR) as a preliminary measurement. RRR measurement results and the estimated parameter from RRR will be reported.
(slides)
11:15~11:25B.H. Hsieh (ICRR)
Assembly of Prototype Sapphire Suspension In this talk, I will discuss the design of cryogenic payload system for KAGRA detector, which includes sapphire suspensions. I will discuss the assembly procedure of sapphire suspension system, and present the results for the sapphire fiber strength test. I will conclude my talk by discussing ongoing and future work.
(slides)
11:25~11:45K. Miyo (ICRR) Geophysics Interferometer (slides)
11:45~12:15N. Kanda (Osaka City U.)
KAGRA data management and analysis We will display a ground structure and status of KAGRA data management and data analysis. KAGAR data which are derrived from the interferometer are transfered to, stored and processed for the data analysis by using computer systems of external sites. The data file generated in KAGRA tunnel will be transfered to external sites (Kashiwa, Osaka) immediatelry. Data are also mirroring in Tier-1 sites: Academia SINICA (Taiwan) and KISTI (Korea). Also partcial data sets are distributed during KAGRA users. Recently, KAGRA introduced 2.5 PiB main storage system. On the other hand, we are proceeding data anlaysis, i.e. gravitational wave event searches at offline. We had some progress using iKAGRA data. In this presentaion, we will display there latest progress of KAGRA data related works.
(slides)
12:15~13:30Lunch
  Chaired by S. Haino (AS IoP)
13:30~13:50T. Yamamoto (ICRR)
Off-line calibration and h-of-t reconstruction of iKAGRADuring iKAGRA operation, a strain signal was generated as on-line h-of-t on real time system. Time variation of an optical gain and actuator efficiencies were not considered in on-line h-of-t. We try to analyze behavior of some calibration lines for regenerating the strain signal as off-line h-of-t. I will report on the progress of off-line calibration of iKAGRA.
(slides)
13:50~14:10Y. Inoue (Academia Sinica) Calibration of bKAGRA (slides)
14:10~14:30T. Yokozawa (Osaka City U.)
Toward the bKAGRA Hardware InjectionHardware injections are one of the important end-to-end test for gravitational wave detectors. To displace the detectors' test mass by an actuator or photon radiation pressure, we can know the detector response of quasi-injected gravitational waves. The main purpose of hardware injection are (1) an additional check of the h(t) calibration (2) test of search and parameter estimation analysis (3) a method to check for cross-couplings to the detectors output channels (4) blind injection. In this talk, we will explain the plan of bKAGRA hardware injection test. From the experience of iKAGRA hardware injection test, we can realize the many technical problems. To improve the hardware injection test performance, we should solve the problems and do R&D studies toward the bKAGRA hardware injection. We also investigate the physical waveform injection with photon calibration system and its performance in each bKAGRA phase.
(slides)
14:30~14:45T. Shishido (Soukendai) Beam position monitor system of KAGRA Photon Calibrator (slides)
14:45~15:00G.C. Liu (TamKang U.) Data management and data analysis in Taiwan (slides)
15:00~15:15Break
  Chaired by Y. Itoh (U. Tokyo)
15:15~15:30L. Tsukada (U. Tokyo)
Application of a zero-latency whitening filter to compact binary coalescence gravitational-wave searchesWe examine the performance of a zero-latency whitening filter in a detection pipeline for compact binary coalescence (CBC) gravitational-wave (GW) signals. We find that the filter reproduces sufficiently consistent signal-to-noise ratio (SNR) for both noise and artificial GW signals (called injections) with the results of the original high latency and phase preserving filter. Additionally, we demonstrate that these two filters have a great agreement of squared-chi value, a discriminator for gravitational wave signals.
(slides)
15:30~15:45D.B. Jia (U. Toyama)
Using Non Harmonic Analysis (NHA) to reduce the influences of line noises for GW Observatory About the real data of detector, the plural line noises are appearing bigger than the gravitational wave greatly, without the notch filter to analyze and observe the gravitational wave signal in detail becomes necessary. Among the various techniques, we proposed and tried to use the Non-Harmonic Analysis (NHA) which improved the frequency resolution dramatically to analyze the gravitational wave. For the model signal of gravitational wave, we compared and verified the analysis accuracy of NHA with other techniques in the time-frequency domain. Using the actual LIGO measured data to verify the analytical precision of gravitational wave signal which near the line noise by NHA. And NHA provides a higher-resolution analysis than other previous methods, even the information of small gravitational wave signal which be covered by the large power supply noise, it can be captured and visualized to the limit by NHA without doing the notch filter.
(slides)
15:45~16:00M. Spinrath (NCTS)
Detection prospects for the Cosmic Neutrino Background using laser interferometersThe cosmic neutrino background is a key prediction of Big Bang cosmology which has not been observed yet. The movement of the earth through this neutrino bath creates a force on a pendulum, as if it was exposed to a cosmic wind. We revise here estimates for the resulting pendulum acceleration and compare it to the theoretical sensitivity of an experimental setup where the pendulum position is measured using current laser interferometer technology as employed in gravitational wave detectors. We discuss how a significant improvement of this setup can be envisaged in a micro gravity environment. The proposed setup could simultaneously function as a dark matter detector in the sub-MeV range, which currently eludes direct detection constraints.
(slides)
  Chaired by N. Kanda (Osaka City U.)
16:00~16:20Y. Itoh (U. Tokyo) Summary of GW sources and physics potentials (slides)
16:20~16:50K. Somiya (Titech) KAGRA future discussions (1) (slides)
16:50~17:05S. Haino (AS IoP)
KAGRA future discussions (2) I would like to encourage and keep physics-driven discussions on the current and future KAGRA sensitivity design and targets by owing the latecomers' benefits.
(slides)
17:05~18:00 Discussions


Program (Monday, May/22)
  Chaired by H.M. Lee (SNU)
09:00~09:30Martin Hewitson (AEI)
LISA Pathfinder: Status and ResultsOn December 3rd 2015 at 04:04 UTC, the European Space Agency launched the LISA Pathfinder satellite on board a VEGA rocket from Kourou in French Guiana. After a series of orbit raising manoeuvres and a 2 month long transfer orbit, LISA Pathfinder arrived at L1. Following a period of commissioning, the science operations commenced on March 1st, beginning the demonstration of technologies and methodologies which pave the way for a future large-scale gravitational wave observatory in space. This talk will discuss the concepts behind a future space-based gravita- tional wave observatory like LISA, make the link to the scientific goals of the LISA Pathfinder mission, discuss the mission results to date, including the mission extension, and coment on the impact of these results on a future LISA-like mission.
(slides)
09:30~09:55Wei-Tou Ni (NTHU)
Overview of Space GW Detection ProposalsGravitational wave (GW) detection in space is aimed at low frequency band (100 nHz - 100 mHz) and middle frequency band (100 mHz - 10 Hz). The science goals are the detection of GWs from (i) Supermassive Black Holes; (ii) Extreme-Mass-Ratio Black Hole Inspirals; (iii) Intermediate-Mass Black Holes; (iv) Galactic Compact Binaries and (v) Relic GW Background. In this paper, we present an overview on the sensitivity, orbit design, basic orbit configuration, angular resolution, orbit optimization, deployment, time-delay interferometry and payload concept of the current proposed GW detectors in space under study. The detector proposals under study have arm length ranging from 1000 km to 1.3 x 109 km (8.6 AU) including (a) Solar orbiting detectors -- ASTROD-GW (ASTROD [Astrodynamical Space Test of Relativity using Optical Devices] optimized for GW detection), BBO (Big Bang Observer), DECIGO (DECi-hertz Interferometer GW Observatory), e-LISA (evolved LISA [Laser Interferometer Space Antenna]), LISA, other LISA-type detectors such as ALIA, TAIJI etc. (in Earth-like solar orbits), and Super-ASTROD (in Jupiter-like solar orbits); and (b) Earth orbiting detectors -- ASTROD-EM/LAGRANGE, GADFLI/GEOGRAWI/g-LISA, OMEGA and TIANQIN.
(slides)
10:55~10:25Hsien-Chi Yeh (SYSU) The preliminary analysis of TIANQIN mission and the development of key technologies (slides)
10:25~10:45Break
  Chaired by S. Miyoki (ICRR)
10:45~11:10Sen Han (USST)
LIGO Mirror Diagnosis and Requirement In LIGO project there is a very key mirror which has super large ROC (radius of curvature). The super large ROC mirror has big effect on both noise sensitivity and stable cavity in gravitational wave (GW) detection. With research proceeding further, there are still a lot of challenges existing in testing the mirror. To solve these problems, one good solution, Fizeau interferometer, will be presented. We change the tradition that curved surface must be measured with a standard curved surface. We use a flat mirror as a reference flat and it can reduce both cost and test requirement a lot. The concave mirrors with the ROC 1.6m to 6km are taken as samples. After the precision measurement and analysis, the experimental results show that relative ROC error is lower than 3%, and it can fully meet the requirements of the measurement of super large ROC mirror. In conclusion, this diagnosis method is simple, fast, non-contact, and highly precision. And it can also provide us a new thought in the measurement of the super large ROC mirror.
(slides)
11:10~11:35Hyung-Mok Lee (SNU)
Terrestrial detector for low frequency gravitational waves based on full tensor measurmentTerrestrial gravitational wave (GW) detectors are mostly based on Michelson-type laser interferometers with arm lengths of a few km to reach a strain sensitivity of 10-23 Hz-1/2 in the frequency range of a few 100 to a few 1000 Hz. There should be a large variety of sources generating GWs at lower frequencies below 10 Hz. However, seismic and Newtonian noise has been serious obstacle in realizing terrestrial low-frequency GW detectors. Here we describe a new GW detector concept by adopting new measurement techniques and configurations to overcome the present low-frequency barrier due to seismic and Newtonian noise. The detector is an extension of the superconducting gravity gradiometer (SGG) that has been developed at the University of Maryland to measure all components of the gravity gradient tensor by orthogonally combining three bars with test masses at each end. The oscillating component of the gravity gradient tensor is the GW strain tensor, but the actual signal is likely to be dominated by Newtonian and seismic noise, whose amplitudes are several orders of magnitude larger than the GWs. We propose to mitigate seismic noise by (a) constructing detector in deep underground, (b) applying passive isolation with pendulum suspension, and (c) using the common-mode rejection characteristic of the detector. The Newtonian noise can be suppressed by combining the components of the gradient tensor with signals detected by seismometers and microphones. By constructing a detector of 100-m long bars cooled to 0.1 K, a strain sensitivity of a few times 10-21 Hz-1/2 can be achieved in the frequency range between 0.1 to 10 Hz. Binaries composed of intermediate mass black holes of 1000 to 10,000 Ms could be detected at distances up to a few Gpc with this detector. Detectable range for the merging white dwarf binaries is up to a few Mpc. Unlike current two-dimensional detectors, our single detector is able to determine the polarization of GWs and the direction to sources on its own.
(slides)
11:35~12:00Albert Kong (NTHU) Multimessenger observations in Taiwan (slides)
12:00~13:30Lunch
  Chaired by Y.H. Chu (ASIAA)
13:30~14:30Gabriela Gonzalez (LSU, Former LSC Spokesperson)
Searching for - and finding! gravitational waves (ASIAA-NTU special joint Colloquium) On September 14 2015, the two LIGO gravitational wave detectors in Hanford, Washington and Livingston, Louisiana registered a nearly simultaneous signal with time-frequency properties consistent with gravitational-wave emission by the merger of two massive compact objects. Further analysis of the signals by the LIGO Scientific Collaboration and the Virgo Collaboration revealed that the gravitational waves detected by LIGO came from the merger of a binary black hole system. This observation, followed by another one in December 2015, marked the beginning of gravitational wave astronomy. I will describe some details of the observation, the status of LIGO and Virgo ground-based interferometric detectors, and prospects for future
(slides)
  Chaired by M. Ando (U. Tokyo)
14:30~15:15Jo Van den Brand (Nikhef, Virgo Spokesperson) Status of Virgo (slides)
15:15~15:55Takaaki Kajita (ICRR, KAGRA PI) Status of KAGRA (slides)
15:55~16:10Break
  Chaired by S. Haino (AS IoP)
16:10~16:40Masaki Ando (U.Tokyo) Science and Design of DECIGO and B-DECIGO (slides)
16:40~17:00Shiuh Chao (NTHU) Mirror coating for next generation detector (slides)
17:00~17:30Y. Michimura (U.Tokyo) KAGRA future discussions (3) (slides)
17:30~17:50 Discussions
17:50~18:00T. Kajita (ICRR) Closing remarks