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We, the members of the Division for Chronological Research at the Institute for Space-Earth Environmental Research at Nagoya University, held a regional contribution program for elementary and junior high school students on August 4–5, 2016: “Investigation of past solar activity and the paeloclimate change from tree annual rings and varved lake sediments.” Thirty-five students and six of their parents observed natural samples to experience earth and archaeological sciences. The first day began with a lecture on how tree annual rings and varved lake sediments can be used to reveal the paleoclimate. After the lecture, the students took part in several hands-on experiments on sedimentology. On the second day they travelled to the Wakasa area by bus and visited the Wakasa-Mikata Jomon Museum to learn about the pre-historic Jomon lifestyle and culture by observing remains from the Jomon Period excavated from the Torihama shell mound. Later in the day they took a cruising observation expedition across Suigetsu Lake, Mikatagoko to observe unique varved sediment layers on a lakebed revealing paleoclimate change dating back 70,000 years. Finally, they observed genuine sediment cores at the Fukui Prefectural Satoyama-Satoumi Research Institute. The program ended a success. The post-program questionnaire shows that the participants enjoyed the program and learned many new things., 年代測定研究部においては、平成28年度総長裁量経費地域貢献事業として、平成28年8月4日（木）と5日（金）の2日間に亘り、小学5年生から中学3年生まで35名を対象とした体験学習「樹木年輪・年縞堆積物から過去の太陽活動、地球の古気候を探る」を実施した。初日は名古屋大学で講義・実習を、2日目はバスで福井県若狭三方五湖に出向き、若狭三方縄文博物館の見学、水月湖の野外調査、ならびに福井県里山里海湖研究所において年縞堆積物の見学を行った。全体的に内容を詰めすぎた感はあるが、参加者は楽しみながら体験学習には取り組んでいた。アンケート結果が示すように、本事業の目的である“小・中学生に自然科学・地球科学・文化財科学等の面白さを伝える”ことは十分に果たされ、地域社会へ貢献できたと考えられる。

The X-ray fluorescence (XRF) analyzer (Shimadzu XRF-1800) of the Division for Chronological Research, Institute for Space‒Earth Environmental Research, Nagoya University, was moved from the Furukawa Hall to the Research Institutes Building II on April 2016. To perform accurate and stable measurements of major elements with the XRF analyzer again after the moving, we examined the optimal analytical condition and remade calibration curves using 44 geochemical reference rock samples from the Geological Survey of Japan. The measurement result using the new calibration curves showed that the measured values were close to the reference values for all major elements except for ones with very low concentrations, indicating that accurate measurement of major elements has been enabled., 名古屋大学宇宙地球環境研究所年代測定研究部は2016年4月に古川記念館から研究所共同館IIに移転し、それに伴い蛍光X線分析装置（島津製作所製XRF-1800）も移設した。そのため、移転後のXRF装置の安定性、分析条件、検量線等について再検討する必要が生じた。本研究においては、岩石標準物質44試料を用いて主成分元素（Si、Ti、Al、Fe、Mn、Mg、Ca、Na、K、P）の検量線を作成し直し、この検量線を使用して岩石標準物質の分析を行った。その結果、いずれの元素においても分析値と推奨値の比の平均はすべて1に近く、また、ばらつきも実用上十分小さいことが示された。以上のことから、本XRF装置により、主成分元素の正確な測定が可能となった。

Electron probe microanalysis (EPMA) is being performed with two electron microprobes (JCXA–733, JEOL, Tokyo) for various applications, including the CHIME dating and quantification of ultra-trace elements at the Division for Chronological Research, Institute for Space-Earth Environmental Research, Nagoya University. One of the electron microprobes is mainly used for the CHIME dating of rock-forming minerals. The other is used for various applications., 名古屋大学宇宙地球環境研究所年代測定研究部では、2台の電子プローブマイクロアナライザー(EPMA）を用いてCHIME年代測定やさまざまな分析を行っている。2016年度はEPMAなどの装置を古川記念館から研究所共同館IIに移設した。これまで2台のEPMAは異なるソフトウェアで制御していたが、装置の改造を行い共通のハードウェア・ソフトウェアで分析することができるようにした．

An AMS system (Model 4130-AMS) dedicated to 14C measurements, built by High Voltage Engineering Europe (HVEE), B.V., The Netherlands, was delivered to Nagoya University in 1996/97. Acceptance tests of its performance on carbon isotope measurements were completed in January of 1999, and routine measurements began in mid-2000. Since completion of the acceptance tests in early 1999, we have encountered a lot of troubles with the machine, particularly in 2002. Since the end of 2002, the machine has worked relatively well, expect for minor problems. The standard deviation (one sigma) of the 14C/12C ratio is around ±0.3% to ±0.4% (a bit larger than the uncertainty of about ±0.3% calculated from 14C counting statistics) and that of the corresponding 13C/12C ratio is ±0.03% to ±0.07%, as are tested for HOxII targets. The number of targets measured was 330, 1430, 2077, 1003, 1,979, 1679, 1772, 1115, 1339, 866, 1300, 1701, 1449, 1634, 1351, 1741, 1156 in each year from 1999 to 2015, respectively, and total number of targets measured by the end of 2015 is 23,921. We briefly describe the maintenance processes and application results of the AMS system in 2015. The Tandetron AMS system at Nagoya University worked rather well in 2015, with only minor failures, such as (1) X-Y direction movement trouble of target surface to change sputtering positions, (2) compressed-air-leakage problem of an air cylinder to exchange targets to be measured, (3) unexpected break down of high voltage of accelerator without any sparks, without any specific reasons, (4) ion source cleaning due to shortage of Cs in the container, (5) high temperature problem of the circulating water for cooling down the power supply system for two high-energy mass-analyzing magnets. The error no. (3) above became a serious problem at last in December, because we cannot reset a system diagnostic alarm concerning a high voltage spark at last. It was finally found out that the problem caused by a malfunction of the spark-detector circuit unit, mounted on the top of the accelerator tank. \In 2015, we also carried out many application programs of 14C measurements. The reports are included in this Proceedings volume., 名古屋大学宇宙地球環境研究所年代測定研究部シンポジウム報告