Yutaro Sekimoto

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We have observed the Orion Molecular Clouds 2 and 3 (OMC-2 and OMC-3) with the Chandra X-ray Observatory (CXO). The northern part of OMC-3 is found to be particularly rich in new X-ray features; four hard X-ray sources are located in and along the filament of cloud cores. Two sources coincide positionally with the submm-mm dust condensations of MMS 2 and 3(More)
We present observations of the P1–P0 fine structure transition of atomic carbon [CI], the J=3–2 transition of CO, as well as of the J=1–0 transitions of CO and CO toward DR15, an HII region associated with two mid-infrared dark clouds (IRDCs). The CO and CO J=1–0 emissions closely follow the dark patches seen in optical wavelength, showing two(More)
N2H + observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare “cores with young stars” with “cores without young stars”. The differences in core radius, linewidth, and core mass are small. Linewidth is dominated by thermal motions in both cases. N2H + maps show that the intensity distribution does not(More)
Kenichi KARATSU†a), Satoru MIMA††, Shugo OGURI†††, Jihoon CHOI††††, R. M. THUSHARA DAMAYANTHI††, Agnes DOMINJON†, Noboru FURUKAWA††, Hirokazu ISHINO†††††, Nonmembers, Hikaru ISHITSUKA††††††, Member, Atsuko KIBAYASHI†††††, Yoshiaki KIBE†††††, Hitoshi KIUCHI†, Kensuke KOGA∗, Masato NARUSE∗∗, Tom NITTA†, Nonmembers, Takashi NOGUCHI†, Member, Takashi OKADA∗∗∗,(More)
We present the experimental and astronomical results of the tunerless waveguide 810GHz SIS receiver. The Nb/AlOx/Nb junctions associated with a broadband tuning circuit, namely parallel connected twin junctions, are fabricated at Nobeyama Radio Observatory. The tuning microstrip line is made of a Nb thin lm. The lowest receiver noise temperature is 580 K(More)
Large scale mapping observations of the P1– P0 fine structure transition of atomic carbon (CI, 492 GHz) and the J=3-2 transition of CO (346 GHz) toward the Orion A molecular cloud have been carried out with the Mt. Fuji submillimeter-wave telescope. The observations cover 9 square degrees, and include the Orion nebula M42 and the L1641 dark cloud complex.(More)
We propose an on-chip spectrometer camera for sub-millimeter astronomy. The camera will be installed to the focal plane of a telescope and be operated at 0.1 K. The camera is composed of three kinds superconducting circuits, such as wideband antennas, band pass filters (BPFs), and Microwave Kinetic Inductance Detectors (MKID) [1]. All components are(More)
In this paper, we report on the design and experimental results of a fix-tuned Superconductor-Insulator-Superconductor (SIS) mixer for Atacama Large Millimeter/submillimeter Array (ALMA) band 8 (385-500GHz) receivers. Nb-based SIS junctions of a current density of 10kA/cm and one micrometer size (fabricated with a two-step lift-off process) are employed to(More)
The “ ∫ -shaped filament” of the Orion A giant molecular cloud was mapped in N2H + J = 1→0, and its northern end, the OMC-2/3 region was observed also in HC3N J = 5→4 and CCS JN = 43 → 32 and 76 → 65. The results are compared with maps of other molecular lines and the dust continuum emission. The N2H + distribution is similar to the dust continuum(More)
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