New Frontier of Gravitational Wave Research

我们已经提高了灵敏度的TAMA 300引力波（GW）探测器在更高的频率，通过实施功率回收计划。同时对探测器的数据采集、光学系统等各部分进行了改进。随着探测器灵敏度的提高和探测器状态的稳定，我们从2003年2月开始与LIGO探测器进行了为期两个月的符合运行。这两个数据的重合搜索结果已经由TAMA-LIGO合作发表。我们已经收集了TAMA 300的3,000多小时的数据，并公布了双星合并产生的啁啾引力波、黑洞形成产生的衰荡引力波和双星产生的连续引力波的上限。我们还在开发下一代探测器LCGT，它的灵敏度比TAMA探测器提高了两个数量级。低温技术、低频隔振技术和高功率激光技术是下一个探测器建造所必需的，这些技术在LCGT探测器中几乎可以使用。我们已经在神冈矿建造了一个100米臂长的低温探测器克利奥，以证明下一个探测器的可行性。我们还建造了一个应变仪来监测地球深部的动态。我们研制了用于探测器的超静音制冷器，对反射镜进行冷却，并在可调谐干涉仪和冷却Rb原子的原子干涉仪的研究方面取得了进展。通过对分赫兹GW源的理论研究，提出了一种空间干涉仪DECIGO。DECIGO作为一种可以观测早期宇宙的探测器而备受关注。我们刚刚开始了实现DECIGO空间探测器的理论和技术研究。通过这个程序，如上所述，.我们可以为在日本建立GW天文学迈出一大步。

We have improved the sensitivity of the TAMA300 gravitational wave (GW) detector at higher frequencies by implementing the power recycling scheme. At the same time, we have made improvements on various parts of the detector such as data aquisition and optical system. With a higher sensitivity and a more stable status of the detector, we performed coincidence run with LIGO detectors for two months from February 2003. The results of the coincidence search among the both data were already published by the TAMA-LIGO collaboration. We have collected over 3,000 hours data of TAMA300 and published the upper limits on the chirp GWs from binary coalescences, ring-down GWs from black hole formation and continuous GWs from pulsars.We are also developing the next generation detector, LCGT which can attain a better sensitivity by two orders compared with TAMA detector. Low temperature techniques, low frequency vibration isolation and high power lasers which are necessary for the construction of the next detector are almost ready to use in the LCGT detector. We have constructed a 100-m arm-length low-temperature detector, CLIO at Kamioka mine to demonstrate the feasibility of the next detector. We also constructed a strain meter to monitor the dynamics of the deep Earth. We developed very quiet refrigerators which will be used in the detector to cool-down the mirrors.We have made progresses at the studies on the tunable interferometers and atomic interferometers with cooled Rb atoms. A space interferometer, DECIGO was proposed from the theoretical study of the deci-heltz GW sources. DECIGO attracts the attention as a detector which can observe the early Universe. We have just stared the theoretical and technical investigation for the realization of the DECIGO space detector. By this program, as described above,. we could make a great step toward the establishment of the GW astronomy in Japan.