New Frontier of Gravitational Wave Research

我们通过实施功率回收方案提高了TAMA300引力波(GW)探测器在更高频率下的灵敏度。同时，对探测器的数据采集、光学系统等各部分进行了改进。为了获得更高的灵敏度和更稳定的状态，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。TAMA-LIGO的合作已经公布了在这两个数据中进行重合搜索的结果。我们已经收集了TAMA300超过3,000小时的数据，公布了来自双星聚结的啁啾GW、来自黑洞形成的衰荡GW和来自脉冲星的连续GW的上限。我们还在开发下一代探测器LCGT，它的灵敏度比TAMA探测器高两个数量级。低温技术、低频隔振技术和高功率激光器是构建下一个探测器所必需的，它们几乎已经准备好用于LCGT探测器。我们在神冈煤矿建造了一个100米长的低温探测器CLIO，以论证下一个探测器的可行性。我们还建造了一台应变仪来监测地球深处的动态。我们开发了非常安静的冰箱，用于探测器冷却反射镜。我们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DECI-HELTZ GW光源的理论研究，提出了一种空间干涉仪DECIGO。DECIGO作为一种能够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。通过该程序，如上所述，。我们可以朝着在日本建立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.