view Abstract Citations (324) References (86) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Survey of CCS, HC 3N, 5N, and NH 3 toward Dark Cloud Cores Their Production Chemistry Suzuki, Hiroko ; Yamamoto, Satoshi Ohishi, Masatoshi Kaifu, Norio Ishikawa, Shin-Ichi Hirahara, Yasuhiro Takano, Shuro observations HC3N, HC5N, NH3 were carried out 49 dark cloud cores to examine the existence a systematic relation between chemical evolution physical clouds. The...

view Abstract Citations (160) References (43) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Mapping Observations of Sulfur-containing Carbon-Chain Molecules in Taurus Molecular Cloud 1 (TMC-1) Hirahara, Yasuhiro ; Suzuki, Hiroko Yamamoto, Satoshi Kawaguchi, Kentarou Kaifu, Norio Ohishi, Masatoshi Takano, Shuro Ishikawa, Shin-Ichi Masuda, Akimasa High-resolution mapping observations TMC-1 using the lines CCS, C3S, C(S-32), and C(S-34) molecules are reported....

Rotational spectra of sulfur-bearing carbon-chain free radicals HC3S and HC4S have been observed for the first time by using a Fabry–Perot type Fourier-transform microwave spectrometer combined with pulsed discharge nozzle. Rotationally cooled (∼1–2 K) HC3S(2Π1/2) HC4S(2Π3/2) in their ground vibronic states produced supersonic jet an Ar-diluted mixtures C2H2 CS2. Transitions isotopic species, HC334S, also same system, those DC3S DC4S C2D2 instead C2H2. The spectral patterns these species...

\ Nitrous oxide (N$_2$O) ice is likely to exist in trans-Neptunian objects such as Pluto and Triton, potentially formed through ultraviolet (UV) radiation from the Sun or cosmic ray irradiation of N$_2$ CO ices. However, mid-infrared spectral characteristics N$_2$O higher temperature regions (90-110 K), changes spectra during UV irradiation, chemical network nitrogen (N$_x$O$_y$) ices remain insufficiently understood. This study aims elucidate these aspects in-situ measurements cryogenic...

view Abstract Citations (35) References (16) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Laboratory Detection of C 5S by Pulsed--Discharge-Nozzle Fourier Transform Microwave Spectroscopy Kasai, Yasuko ; Obi, Kinichi Ohshima, Yasuhiro Hirahara, Endo, Yasuki Kawaguchi, Kentarou Murakami, Akinori The rotational spectrum C5S in the X 1Sigma+(v = 0) ground state has been observed for first time using a Fabry-Perot-type transform microwave spectrometer combined...

view Abstract Citations (32) References (16) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Laboratory Detection of a New Free Radical C 4S ( 3 Sigma -) Hirahara, Yasuhiro ; Ohshima, Endo, Yasuki A free radical C4S has been detected for the first time by using Fabry-Perot-type Fourier-transform microwave spectrometer combined with pulsed discharge nozzle. Rotationally cooled (about 1-2 K) in its ground electronic state (3Sigma-) produced supersonic jet...

view Abstract Citations (35) References (38) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Observations of Molecular Envelopes Late-Type Stars: CRL 618, 2688, 3068, and CIT 6 Fukasaku, Sadafumi ; Hirahara, Yasuhiro Masuda, Akimasa Kawaguchi, Kentarou Ishikawa, Shin-Ichi Kaifu, Norio Irvine, William M. The HC3N, HC5N, HC7N, CCH, C4H, SiS, HNC molecules were observed in the circumstellar envelopes 6, 3068 with Nobeyama 45 m radio telescope. relative...

view Abstract Citations (16) References (12) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Laboratory Detection of HNCCC and DNCCC by Pulsed Discharge Nozzle Fourier-Transform Microwave Spectroscopy Hirahara, Yasuhiro ; Ohshima, Endo, Yasuki Details are reported here the first laboratory detection low-J rotational transitions DNCCC. The quadrupole coupling constants N-14 D nuclei in determined for time. bond length H-N is evaluated from obtained models,...

view Abstract Citations (24) References (11) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Detection of Five 13C Isotopic Species HC 5N in TMC-1 Takano, Shuro ; Suzuki, Hiroko Ohishi, Masatoshi Ishikawa, Shin-Ichi Kaifu, Norio Hirahara, Yasuhiro Masuda, Akimasa Observations the cyanopolyyne peak Taurus Molecular Cloud 1, obtained using a 32-50-GHz double-sideband mixer-receiver on 45-m telescope at Nobeyama Radio Observatory during June and September 1987...

The gas-phase absorption spectrum of the ν3 band cyclopropenylidene (cyclic C3H2 ) has been observed with a high-resolution Fourier transform infrared spectrometer. ring molecule was generated by microwave discharge in an allene and Ar mixture. between 1250 1305 cm−1 analyzed using Watson’s A-reduced Hamiltonian to determine origin (ν0=1277.3711±0.0001 ), rotational constants, centrifugal distortion constants state.

We present a preliminary optical design and layout for the mid-infrared (4-18 μm) high-resolution spectrograph SPICA, Japanese next-generation space IR observatory with 3.5 m telescope. MIR spectroscopy is powerful probe to study gas-phase molecules/atoms in variety of astronomical objects. Space observation provides great opportunity many molecular lines especially between atmospheric windows. SPICA gives us chance realize from large telescope aperture. The major technical challenge size...

Although the Moon has been investigated from Earth, manned Apollo program, and numerous unmanned spacecraft including latest Clementine Lunar Prospector, unresolved issues on origin evolution of still exist. To find clues or hopefully answers to these issues, Japan will send, Moon, an orbiting called Selenological Engineering Explore (SELENE) equipped with a suite state-of-the-art mission instruments. Spectral Profiler (SP) is one instrument onboard SELENE, obtain 0.5-2.6 micrometers...

We have been developing an immersion grating for high-resolution spectroscopy in the mid-infrared (MIR) wavelength region. A MIR (12-18 µm) (R = 20,000-30,000) spectrograph with is proposed SPICA, Japanese next-generation space telescope. The instrument will be world's first space, and it would make great impacts on infrared astronomy. To realize a high-efficiency grating, optical properties machinability of bulk materials are critical issues. There three candidate good transmittance; CdTe...

In Jupiter's stratosphere, gaseous carbon monosulfide (CS) was first discovered in 1994 by millimeter and ultraviolet observations as a product induced the collision of comet Shoemaker-Levy 9 (SL9). {To constrain sulfur chemistry, 2013, 19 years after SL9 event, we observed stratospheric CS $J$=7 -- 6 rotational transition at 0.8 mm wavelength using Atacama Submillimeter Telescope Experiment (ASTE) 10-m single dish telescope. The molecular line successfully detected with 120 mK intensity...

The mid-infrared high dispersion spectrograph (IRHS; tentative name) with a resolving power of 200,000 at 10 μm is candidate the second-generation instrument for 8.2m Subaru Telescope. A germanium immersion grating will be employed as dispersing element this instrument. Germanium gratings prototype IRHS were successfully fabricated by using nano precision 3D profile grinding/turning machine and ELID grinding method on diamond machining. As result, observed to have grooves ideal saw-tooth...

Step-scan Fourier-transform infrared (FTIR) absorption spectroscopy has been used to study large clusters of C2H2 and C2D2 formed in pulsed supersonic jets. The ν3 stretching bands the spectra have measured near 3230 2400 cm-1, respectively. band positions show formation acetylene nanoclusters with cubic solid structure. deuterium isotopic shift is good agreement predictions based on harmonic oscillator model confirms assignment observed features C2D2. This first observation C2D2, C−D was at...

view Abstract Citations (19) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Sequential Star Formation in Taurus Molecular Cloud 1 Hanawa, Tomoyuki ; Yamamoto, Satoshi Hirahara, Yasuhiro We discuss the fragmentation of a filamentary cloud on basis 1-dimensional hydrodynamical simulation self-gravitating gas cloud. The shows that dense cores are produced with semi-regular interval space and time from one edge to other. At initial stage near...