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Comprehensive Summary: Preparation of large rylenes often needs the use of solubilizing groups along the rylene backbone, which results in the distortion of the skeleton and thus broadening of the absorption spectrum. In this work, we successfully synthesized 2,5,8,16,19,22‐hexakis[2,6‐ bis(tri‐fluoromethyl)phenyl]hexarylene (H) by using an oxidative fusion reaction of perylene trimer in 5% yield. The product is soluble in common organic solvents and could be purified with column chromatography. Single‐crystal X‐ray diffraction analysis revealed that the hexarylene core is not disturbed by the substituents very much and is almost planar. The longest absorption of H exhibits a sharp peak at 831 nm and an on‐set at 875 nm in toluene with a small full‐width‐at‐half‐maximum (FWHM) of 660 cm‐1. The molar extinction coefficient is as large as 131,000 M‐1 cm‐1. The substituents could not perturb the electronic properties of the hexarylene because aryl groups are perpendicular to the hexarylene core and the carbon atoms at 2,5,16,19‐positions have negligible coefficients on its HOMO and LUMO, estimated by theoretical calculations. As a result, the hexarylene having less absorption at the visible light region was stable enough in solution under the LED room light for more than 1 week. This strategy gives a useful guideline to establish the near‐infrared materials that exhibit stability under ambient conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Preparation of large rylenes often needs the use of solubilizing groups along the rylene backbone, which results in the distortion of the skeleton and thus broadening of the absorption spectrum. In this work, we successfully synthesized 2,5,8,16,19,22‐hexakis[2,6‐ bis(tri‐fluoromethyl)phenyl]hexarylene (H) by using an oxidative fusion reaction of perylene trimer in 5% yield. The product is soluble in common organic solvents and could be purified with column chromatography. Single‐crystal X‐ray diffraction analysis revealed that the hexarylene core is not disturbed by the substituents very much and is almost planar. The longest absorption of H exhibits a sharp peak at 831 nm and an on‐set at 875 nm in toluene with a small full‐width‐at‐half‐maximum (FWHM) of 660 cm‐1. The molar extinction coefficient is as large as 131,000 M‐1 cm‐1. The substituents could not perturb the electronic properties of the hexarylene because aryl groups are perpendicular to the hexarylene core and the carbon atoms at 2,5,16,19‐positions have negligible coefficients on its HOMO and LUMO, estimated by theoretical calculations. As a result, the hexarylene having less absorption at the visible light region was stable enough in solution under the LED room light for more than 1 week. This strategy gives a useful guideline to establish the near‐infrared materials that exhibit stability under ambient conditions. [ABSTRACT FROM AUTHOR]

The Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is a future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could have been produced during the inflationary period right after the birth of the Universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the Universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry–Pérot Michelson interferometers with an arm length of 1000 km. Three DECIGO clusters will be placed far from each other, and the fourth will be placed in the same position as one of the other three to obtain correlation signals for the detection of primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder for DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand multi-messenger astronomy. [ABSTRACT FROM AUTHOR]

LISA is a space gravitational-wave mission that will open the unexplored gravitational-wave frequency window at around millihertz, shedding light on the study of supermassive black holes and the nature of gravity. The LISA project has been propelled by international collaboration in order to maximize the scientific outcome. With the aim of making scientifically important contributions to LISA, instrument and science groups were newly formed in Japan. This article summarizes the current status of the contribution activities conducted by each group to date, highlighting a few selected topics including the development of photoreceivers and theoretical studies on compact binaries and extreme mass ratio inspirals. [ABSTRACT FROM AUTHOR]

Scientific analysis for the gravitational wave detector LISA will require theoretical waveforms from extreme-mass-ratio inspirals (EMRIs) that extensively cover all possible orbital and spin configurations around astrophysical Kerr black holes. However, on-the-fly calculations of these waveforms have not yet overcome the high dimensionality of the parameter space. To confront this challenge, we present a user-ready EMRI waveform model for generic (eccentric and inclined) orbits in Kerr spacetime, using an analytical self-force approach. Our model accurately covers all EMRIs with arbitrary inclination and black hole spin, up to modest eccentricity (≲0.3) and separation (≳2-10  M from the last stable orbit). In that regime, our waveforms are accurate at the leading "adiabatic" order, and they approximately capture transient self-force resonances that significantly impact the gravitational wave phase. The model fills an urgent need for extensive waveforms in ongoing data-analysis studies, and its individual components will continue to be useful in future science-adequate waveforms.