The purpose of this lecture it to learn the basic concepts of the gravitational wave data analysis. In
this lecture, we focus on the analysis of the gravitational waves from inspiraling compact binaries,
which are consider to be the most promising sources for ground based detectors. First we
introduce the concept of the maximum likelihood method and derive the basic formula of the
matched filtering. We then discuss the application of the matched filtering to the analysis of the
inspiraling compact binaries.
Ref. (1) M. Maggiore, "Gravitational waves volume 1: theory and experiment" (2008). Section 7.
Ref. (2) J.D.E. Creighton and W.G. Anderson, "Gravitational-wave physics and astronomy" (2011),
Section 7.
Ref. (3) P. Jaranowski and A. Krolak, "Analysis of Gravitational-wave data" (2009).
Ref. (4) B.S. Sathyaprakash and B. F. Schutz, Living Rev. Relativity 12 (2009), 2.
K. Hayama (Osaka City University):
“Fundamentals of the gravitational wave data analysis III, IV”
……
Kenichi Oohara (Niigata University):
“Fundamentals of the gravitational wave data analysis V”
The Hilbert-Huang transform (HHT) is a novel, adaptive approach to time series analysis. It does
not impose a basis set on the data or otherwise make assumptions about the data form, and so the
time-frequency decomposition is not limited by spreading due to uncertainty. Because of the high
resolution of the time-frequency, the HHT is promising for search for gravitational waves,
investigating properties of detected gravitational waves and examining detector characterization. I
will review the method of the HHT and report recent results of our research.
References:
1) N.E. Huang, S.R. Long and Z. Shen; "The mechanism for frequency downshift in nonlinear wave
evolution," Adv. Appl. Mech., Vol. 32 (1996) 59–111.
2) N.E. Huang et al.; "The empirical mode decomposition and the Hilbert spectrum for nonlinear and
non-stationary time series analysis,” Proc. R. Soc. London Ser. A, Vol. 454 (1998) 903–993.
3) H. Takahashi, K. Oohara, M. Kaneyama, Y. Hiranuma and J.B. Camp; "On Investigating EMD
Parameters to Search for Gravitational Waves," Advances in Adaptive Data Analysis, Vol. 5 (2013)
1350010.
Aug 10
Miok Park (U of Waterloo):
“Deformations of Lifshitz holography with the Gauss-Bonnet term in (n+1) dimensions”
We investigate deformations of Gauss-Bonnet-Lifshitz holography in (n+1) dimensional spacetime.
Marginally relevant operators are dynamically generated by a momentum scale Lambda ~ 0 and
correspond to slightly deformed Gauss-Bonnet-Lifshitz spacetimes via a holographic picture. To
admit (non-trivial) sub-leading orders of the asymptotic solution for the marginal mode, we find that
the value of the dynamical critical exponent z is restricted by z= n-1-2(n-2) tilde{alpha}, where
tilde{alpha} is the (rescaled) Gauss-Bonnet coupling constant. The generic black hole solution,
which is characterized by the horizon flux of the vector field and tilde{alpha}, is obtained in the
bulk, and we explore its thermodynamic properties for various values of n and tilde{alpha}.
Dongfeng Gao (Wuhan Institute of Physics and Mathematics):
“Gravitational-wave Detection With Matter-wave Interferometers Based On Standing Light
Waves”
We study the possibility of detecting gravitational-waves with matter-wave interferometers, where
atom beams are split, deflected and recombined totally by standing light waves. Our calculation
shows that the phase shift is dominated by terms proportional to the time derivative of the
gravitational wave amplitude. Taking into account future improvements on current technologies, it is
promising to build a matter-wave interferometer detector with desired sensitivity.
Yun Kau Lau (AMSS):
“Coevolution of black holes-galaxies and space detection of gravitational waves"
The talk will present an overview on the latest development of the space detection of gravitational waves
program in the Chinese Academy of Sciences in China. I will outline the long term roadmap of the program, the
preliminary mission design together with the main science driver of the mission in tracking the cosmic growth
of supermassive massive black holes at the center of galaxies. Progress in the experimental side of the program
will also be sketched.
Junwei Cao (Tsinghua U):
“Summary of Gravitational Wave Research Activities at Tsinghua University”
The LSC group at Tsinghua University is the only LSC member in mainland China. Its contribution to
LIGO currently revolves around the use of modern computing techniques: virtual machines, GPU
acceleration, and advanced algorithms. The four research lines followed in the group in preparation
for Advanced LIGO are presented.
Yuta Michimura (U of Tokyo):
“Alignment Sensing and Control for the KAGRA interferometer”
KAGRA is a cryogenic interferometric gravitational wave detector which is under construction at the
underground site of Kamioka mine. In order to achieve the fundamental sensitivity of KAGRA, mirror
motions of the interferometer must be finely controlled. However, the alignment control of mirrors
will be one of the most challenging issue because of angular instability of the arm cavities and high
degeneracy of alignment signals from each mirror. Also, complexity of the KAGRA cryogenic
suspension makes this issue more challenging. I will present recent results from a model we
developed for simulating the alignment sensing and control scheme.
Ayaka Shoda (U of Tokyo):
“A New Detector for Low-Frequency Gravitational Waves: Torsion-bar Antenna”
Gravitational wave (GW) astronomy will reveal the new aspect of our universe. Examples of
interesting targets that we can observe only by GWs are black hole binaries and a stochastic
gravitational wave background (SGWB). However, the ground-based interferometers and other
ground based detectors do not have good sensitivity below 10 Hz though the main frequency of
GWs from black hole binaries and a SGWB is lower. Then, we developed novel detector Torsion-bar
Antenna (TOBA). TOBA is fundamentally sensitive around 0.1 - 1.0 Hz even on the ground. We have
already developed first prototypes and performed a SGWB search. This work set a first upper limit
on a SGWB around 0.2 Hz. Now we are upgrading the prototype as a next step. I will introduce our
experiment and a future plan.
Yusuke Sakakibara (U of Tokyo):
“Cooling time reduction of KAGRA”
In interferometric cryogenic gravitational wave detectors, such as KAGRA in Japan, there are plans
to cool mirrors and their suspension systems (payloads) in order to reduce thermal noise, that is,
one of the fundamental noise sources. Because of the large payload masses (several hundred kg
in total) and their thermal isolation, a cooling time of several months is required. Our calculation
shows that a high-emissivity coating (e.g. a diamond-like carbon (DLC) coating) can reduce the
cooling time effectively by enhancing radiation heat transfer. Here, we have experimentally verified
the effect of the DLC coating on the reduction of the cooling time.
Yuki Susa (Tokyo Institute of Technology):
“Review of the SQL in Gravitational Wave Detection”
The Standard Quantum Limit (SQL) was proposed as the accurate limit for measuring free mass
position in 1980’s. There were controversies about the possibility of beating the SQL. It is the
important problem for improving the sensitivity of gravitational wave detectors. It is also the
interesting issue in quantum measurement. Nowadays we know that the SQL can be beat. But there
are difference opinions about the way to beat. In this talk, I give the briefly review of the SQL in
quantum measurement scheme and future problems which should be addressed.