[Speaker 1]
GIONO Gabriel, D2, SOKENDAI, Mitaka（supervisor：Suematsu Yoshinori, Katsukawa Yukio, Hara Hirohisa）
[Title]
Current progress on the CLASP telescope alignment.
[Abstract]
The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) is a sounding rocket instrument currently under development at NAOJ. CLASP aims to measure for the first time the polarization of the Lyman-Alpha line (121.6nm) emitted from the solar upper-chromosphere and transition region, and derived the magnetic field strength and orientation through the Hanle effect.
CLASP instrument is composed of a classical Cassegrain telescope focusing the light inside an inverse-mount Wadsworth spectrograph. A polarization analyzer is located on both of the two channels, and a rotating half-waveplate is used for the polarization modulation.
As part of CLASP development, both telescope’s primary and secondary mirrors have to be properly align in order to ensure a good image and spectrum quality.
In this colloquium, the current progress on the telescope’s alignment will be presented. As an introduction, the experiment “double-pass” configuration will be explained as well as the basic principle of telescope’s alignment. Then, the measured wavefront error (WFE) and how it was retrieved from the interferences fringes will be shown. Finally, the adjustment estimation on the secondary mirror tilt will be derived by comparing the WFE aberration coefficient to ray-tracing simulations.

[Speaker 1]
Taiki Suzuki, D1, SOKENDAI, Mitaka（supervisor：Masatoshi Ohishi）
[Title]
Survey Observations and Formation Process of Methylenimine (CH2NH)

[Speaker 2]
Jun Toshikawa, D3, SOKENDAI, Mitaka（supervisor：Nobunari Kashikawa）
[Title]
High Redshift Protoclusters: comparison with theoretical model

[Speaker 1]
Rhythm Shimakawa M2, SOKENDAI, Mitaka（supervisor : Kodama Tadayuki）
[Title]
Metal enhancement of the protocluster galaxies at z=2.2
[Abstract]
Protoclusters are the ideal laboratories to study how the strong environmental dependence in galaxy properties seen today was initially set up. We conducted a near-infrared spectroscopy of star-forming galaxies (H-alpha emitters) associated with two protoclusters at z=2.2&2.5 with MOIRCS/Subaru.
Shimakawa et al. (2014) have confirmed that the two protoclusters are the right ancestors of today’s largest clusters like ‘Coma’, and now we are studying the physical characteristics of the memberships in the respective protoclusters.
This talk focuses on one of our recent results regarding the environmental dependence of mass-metallicity relation seen in the protocluster, PKS1138-262 at z=2.2. The mass-metallicity relation provides crucial insights into star formation history, gaseous inflows and outflows.
As a result, we find a clear excess of the gaseous metallicities of the protocluster galaxies at the stellar mass of < 1E11 Msun. We suggest that it can be explained by the 'downsizing effect' or 'gas recycling' in the protocluster region.

3月31日、三鷹キャンパスにて専攻修了式が執り行われました。
平成25年度修了生のうち4名が出席し、教員・在学生に盛大に見送られました。

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3月10日（月）～13日（木）までの4日間、国立天文台三鷹キャンパスで、総研大・国立天文台スプリングスクールが開校されました。

平成23年から始まったスプリングスクール。4回目を迎えた今回は、全国26大学・高専から46名もの参加者が集まりました。
装置開発を含む最先端の天文学の基礎を学ぶということで、今年は、5名の講師が、電波天文学、太陽物理学、理論天文学、星間物理学、光赤外線天文学と幅広い分野の講義を担当しました。

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