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We are developing an ultra-wideband spectroscopic instrument, DESHIMA (DEep Spectroscopic HIgh-redshift MApper), based on the technologies of an on-chip filter-bank and Microwave Kinetic Inductance Detector (MKID) to investigate dusty star-burst galaxies in the distant universe at millimeter and submillimeter wavelength. An on-site experiment of DESHIMA was performed using the ASTE 10-m telescope. We established a responsivity model that converts frequency responses of the MKIDs to line-of-sight brightness temperature. We estimated two parameters of the responsivity model using a set of skydip data taken under various precipitable water vapor (PWV, 0.4-3.0 mm) conditions for each MKID. The line-of-sight brightness temperature of sky is estimated using an atmospheric transmission model and the PWVs. As a result, we obtain an average temperature calibration uncertainty of $1\sigma=4$%, which is smaller than other photometric biases. In addition, the average forward efficiency of 0.88 in our responsivity model is consistent with the value expected from the geometrical support structure of the telescope. We also estimate line-of-sight PWVs of each skydip observation using the frequency response of MKIDs, and confirm the consistency with PWVs reported by the Atacama Large Millimeter/submillimeter Array., Comment: Accepted for publication in the Journal of Low Temperature Physics for LTD-18 special issue

Integrated superconducting spectrometer (ISS) technology will enable ultra-wideband, integral-field spectroscopy for (sub)millimeter-wave astronomy, in particular, for uncovering the dust-obscured cosmic star formation and galaxy evolution over cosmic time. Here we present the development of DESHIMA 2.0, an ISS for ultra-wideband spectroscopy toward high-redshift galaxies. DESHIMA 2.0 is designed to observe the 220-440 GHz band in a single shot, corresponding to a redshift range of $z$=3.3-7.6 for the ionized carbon emission ([C II] 158 $\mu$m). The first-light experiment of DESHIMA 1.0, using the 332-377 GHz band, has shown an excellent agreement among the on-sky measurements, the lab measurements, and the design. As a successor to DESHIMA 1.0, we plan the commissioning and the scientific observation campaign of DESHIMA 2.0 on the ASTE 10-m telescope in 2023. Ongoing upgrades for the full octave-bandwidth system include the wideband 347-channel chip design and the wideband quasi-optical system. For efficient measurements, we also develop the observation strategy using the mechanical fast sky-position chopper and the sky-noise removal technique based on a novel data-scientific approach. In the paper, we show the recent status of the upgrades and the plans for the scientific observation campaign., Comment: 9 pages, 4 figures, 1 table, accepted for publication in the Journal of Low Temperature Physics for the LTD19 special issue

The next technological breakthrough in millimeter–submillimeter astronomy is three-dimensional imaging spectrometry with wide instantaneous spectral bandwidths and wide fields of view. The total optimization of the focal-plane instrument, the telescope, the observing strategy, and the signal-processing software must enable efficient removal of foreground emission from the Earth’s atmosphere, which is time-dependent and highly nonlinear in frequency. Here, we present Time-dependent End-to-end Model for Post-process Optimization (TiEMPO) of the DEep Spectroscopic HIgh-redshift MApper (DESHIMA) spectrometer. TiEMPO utilizes a dynamical model of the atmosphere and parameterized models of the astronomical source, the telescope, the instrument, and the detector. The output of TiEMPO is a time stream of sky brightness temperature and detected power, which can be analyzed by standard signal-processing software. We first compare TiEMPO simulations with an on-sky measurement by the wideband DESHIMA spectrometer, and find good agreement in the noise and sensitivity. We then use TiEMPO to simulate the detection of the line emission spectrum of a high-redshift galaxy using the DESHIMA 2.0 spectrometer in development. The TiEMPO model is open source. Its modular and parametrized design enables users to adapt it to optimize the end-to-end performance of spectroscopic and photometric instruments on existing and future telescopes, Journal of Astronomical Telescopes, Instruments, and Systems, 8 (2), ISSN:2329-4221, ISSN:2329-4124

We present ALMA [CII] line and far-infrared (FIR) continuum observations of seven z > 6 low-luminosity quasars (M1450 > −25 mag) discovered by our on-going Subaru Hyper Suprime-Cam survey. The [CII] line was detected in all targets with luminosities of ∼(2−10) × 108 L⊙, about one order of magnitude smaller than optically luminous quasars. Also found was a wide scatter of FIR continuum luminosity, ranging from LFIR < 1011L⊙ to ∼2 × 1012L⊙. With the [CII]-based dynamical mass, we suggest that a significant fraction of low-luminosity quasars are located on or even below the local Magorrian relation, particularly at the massive end of the galaxy mass distribution. This is a clear contrast to the previous finding that luminous quasars tend to have overmassive black holes relative to the relation. Our result is expected to show a less-biased nature of the early co-evolution of black holes and their host galaxies.

Recent developments in (sub-)millimeter facilities have drastically changed the amount of information obtained from extragalactic spectral scans. In this paper, we present a feature extraction technique using principal component analysis (PCA) applied to arcsecond-resolution (1.0-2.0 arcsec = 72-144 pc) spectral scan datasets for the nearby type-2 Seyfert galaxy, NGC 1068, using Band 3 of the Atacama Large Millimeter/submillimeter Array. We apply PCA to 16 well-detected molecular line intensity maps convolved to a common 150 pc resolution. In addition, we include the [SIII]/[SII] line ratio and [CI] $^3P_1$-$^3P_0$ maps in the literature, both of whose distributions show remarkable resemblance with that of a kpc-scale biconical outflow from the central AGN. We identify two prominent features: (1) central concentration at the circumnuclear disk (CND) and (2) two peaks across the center that coincide with the biconical outflow peaks. The concentrated molecular lines in the CND are mostly high-dipole molecules (e.g., H$^{13}$CN, HC$_3$N, and HCN). Line emissions from molecules known to be enhanced in irradiated interstellar medium, CN, C$_2$H, and HNC, show similar concentrations and extended components along the bicone, suggesting that molecule dissociation is a dominant chemical effect of the cold molecular outflow of this galaxy. Although further investigation should be made, this scenario is consistent with the faintness or absence of the emission lines from CO isotopologues, CH$_3$OH, and N$_2$H$^+$, in the outflow, which are easily destroyed by dissociating photons and electrons., 15 pages, 6 figures, 2 tables, accepted for publication in ApJ

We present a concept of a millimeter wavefront sensor that allows real-time sensing of the surface of a ground-based millimeter/submillimeter telescope. It is becoming important for ground-based millimeter/submillimeter astronomy to make telescopes larger with keeping their surface accurate. To establish `millimetric adaptive optics (MAO)' that instantaneously corrects the wavefront degradation induced by deformation of telescope optics, our wavefront sensor based on radio interferometry measures changes in excess path lengths from characteristic positions on the primary mirror surface to the focal plane. This plays a fundamental role in planned 50-m class submillimeter telescopes such as LST and AtLAST., 9 pages, 5 figures. Published in SPIE Proc

The integrated superconducting spectrometer (ISS) enables ultra-wideband, large field-of-view integral-field-spectrometer designs for mm-submm wave astronomy. DESHIMA 2.0 is a single-pixel ISS spectrometer for the ASTE 10-m telescope, designed to observe the 220-440 GHz band in a single shot, corresponding to a [CII] redshift range of z=3.3-7.6. The first-light experiment of DESHIMA, using a 332-377 GHz configuration has shown excellent consistency between the performance derived from on-sky measurements, lab-measurements and the design. Ongoing upgrades towards the octave-bandwidth full system include the development of a filterbank chip with ~350 channels and higher optical efficiency, a wideband quasioptical design, and observing methods for efficiently removing the atmosphere.

We report the current status of the NASCO (NAnten2 Super CO survey as legacy) project which aims to provide all-sky CO data cube of southern hemisphere using the NANTEN2 4-m submillimeter telescope installed at the Atacama Desert through developing a new multi-beam receiver and a new telescope control system. The receiver consists of 5 beams. The four beams, located at the four corners of a square with the beam separation of 720′′, are installed with a 100 GHz band SIS receiver having 2-polarization sideband-separation filter. The other beam, located at the optical axis, is installed with a 200 GHz band SIS receiver having 2-polarization sideband-separation filter. The cooled component is modularized for each beam, and cooled mirrors are used. The IF bandwidths are 8 and 4 GHz for 100 and 200 GHz bands, respectively. Using XFFTS spectrometers with a bandwidth of 2 GHz, the lines of 12CO, 13CO, and C18O of J=1−0 or J=2−1 can be observed simultaneously for each beam. The control system is reconstructed on the ROS architecture, which is an open source framework for robot control, to enable a flexible observation mode and to handle a large amount of data. The framework is commonly used and maintained in a robotic field, and thereby reliability, flexibility, expandability, and efficiency in development are improved as compared with the system previously used. The receiver and control system are installed on the NANTEN2 telescope in December 2019, and its commissioning and science verification are on-going. We are planning to start science operation in early 2021.

The next technological breakthrough in millimeter-submillimeter astronomy is 3D imaging spectrometry with wide instantaneous spectral bandwidths and wide fields of view. The total optimization of the focal-plane instrument, the telescope, the observing strategy, and the signal-processing software must enable efficient removal of foreground emission from the Earth's atmosphere, which is time-dependent and highly nonlinear in frequency. Here we present TiEMPO: Time-Dependent End-to-End Model for Post-process Optimization of the DESHIMA Spectrometer. TiEMPO utilizes a dynamical model of the atmosphere and parametrized models of the astronomical source, the telescope, the instrument, and the detector. The output of TiEMPO is a time-stream of sky brightness temperature and detected power, which can be analyzed by standard signal-processing software. We first compare TiEMPO simulations with an on-sky measurement by the wideband DESHIMA spectrometer and find good agreement in the noise power spectral density and sensitivity. We then use TiEMPO to simulate the detection of a line emission spectrum of a high-redshift galaxy using the DESHIMA 2.0 spectrometer in development. The TiEMPO model is open source. Its modular and parametrized design enables users to adapt it to design and optimize the end-to-end performance of spectroscopic and photometric instruments on existing and future telescopes., Presented at SPIE Astronomical Telescopes + Instrumentation 2020. Full published paper, poster and video available at https://doi.org/10.1117/12.2561014 Open-source Python package of TiEMPO: https://pypi.org/project/tiempo-deshima/ Open-source code of TiEMPO: https://zenodo.org/record/4279086#.X_jAsdhKg2w

We present ALMA [CII] line and far-infrared (FIR) continuum observations of three $z > 6$ low-luminosity quasars ($M_{\rm 1450} > -25$) discovered by our Subaru Hyper Suprime-Cam (HSC) survey. The [CII] line was detected in all three targets with luminosities of $(2.4 - 9.5) \times 10^8~L_\odot$, about one order of magnitude smaller than optically luminous ($M_{\rm 1450} \lesssim -25$) quasars. The FIR continuum luminosities range from $< 9 \times 10^{10}~L_\odot$ (3$��$ limit) to $\sim 2 \times 10^{12}~L_\odot$, indicating a wide range in star formation rates in these galaxies. Most of the HSC quasars studied thus far show [CII]/FIR luminosity ratios similar to local star-forming galaxies. Using the [CII]-based dynamical mass ($M_{\rm dyn}$) as a surrogate for bulge stellar mass ($M_{\rm bulge}$), we find that a significant fraction of low-luminosity quasars are located on or even below the local $M_{\rm BH} - M_{\rm bulge}$ relation, particularly at the massive end of the galaxy mass distribution. In contrast, previous studies of optically luminous quasars have found that black holes are overmassive relative to the local relation. Given the low luminosities of our targets, we are exploring the nature of the early co-evolution of supermassive black holes and their hosts in a less biased way. Almost all of the quasars presented in this work are growing their black hole mass at much higher pace at $z \sim 6$ than the parallel growth model, in which supermassive black holes and their hosts grow simultaneously to match the local $M_{\rm BH} - M_{\rm bulge}$ relation at all redshifts. As the low-luminosity quasars appear to realize the local co-evolutionary relation even at $z \sim 6$, they should have experienced vigorous starbursts prior to the currently observed quasar phase to catch up with the relation., 19 pages, 11 figures, 4 tables. Accepted for publication in Publications of the Astronomical Society of Japan (PASJ)

We present a 4.7σ detection of the [OIII] 88 μm line in a gravitationally-lensed Lyman break galaxy, RXC J2248-ID3, using the Atacama Large Millimeter/submillimeter Array (ALMA). We did not detect [CII] 158 μm and rest-frame 90 μm dust continuum emission, suggesting that the bulk of the interstellar medium (ISM) is ionized. Our two-component SED model combining the previous Hubble Space Telescope (HST) data and new photometry obtained from Very Large Telescope (VLT), Spitzer and ALMA suggests the presence of young (∼2 Myr) and mature (∼600 Myr) stellar components with the metallicity of Z = 0.2Z⊙. Our findings are in contrast with previous results claiming a very young, metal-poor stellar component.

For submillimeter spectroscopy with ground-based single-dish telescopes, removing noise contribution from the Earth's atmosphere and the instrument is essential. For this purpose, here we propose a new method based on a data-scientific approach. The key technique is statistical matrix decomposition that automatically separates the signals of astronomical emission lines from the drift noise components in the fast-sampled (1--10 Hz) time-series spectra obtained by a position-switching (PSW) observation. Because the proposed method does not apply subtraction between two sets of noisy data (i.e., on-source and off-source spectra), it improves the observation sensitivity by a factor of $\sqrt{2}$. It also reduces artificial signals such as baseline ripples on a spectrum, which may also help to improve the effective sensitivity. We demonstrate this improvement by using the spectroscopic data of emission lines toward a high-redshift galaxy observed with a 2-mm receiver on the 50-m Large Millimeter Telescope (LMT). Since the proposed method is carried out offline and no additional measurements are required, it offers an instant improvement on the spectra reduced so far with the conventional method. It also enables efficient deep spectroscopy driven by the future 50-m class large submillimeter single-dish telescopes, where fast PSW observations by mechanical antenna or mirror drive are difficult to achieve., Comment: 30 pages, 11 figures, 6 tables, accepted for publication in AJ

We propose a new observing method for single-dish millimeter and submillimeter spectroscopy using a heterodyne receiver equipped with a frequency-modulating local oscillator (FMLO). Unlike conventional switching methods, which extract astronomical signals by subtracting the reference spectra of off-sources from those of on-sources, the FMLO method does not need to obtain any off-source spectra; rather, it estimates them from the on-source spectra themselves. The principle is a high dump-rate (10 Hz) spectroscopy with radio frequency modulation (FM) achieved by fast sweeping of a local oscillator (LO) of a heterodyne receiver: Because sky emission (i.e., off-source) fluctuates as $1/f$-type and is spectrally correlated, it can be estimated and subtracted from time-series spectra (a timestream) by principal component analysis. Meanwhile astronomical signals remain in the timestream since they are modulated to a higher time-frequency domain. The FMLO method therefore achieves (1) a remarkably high observation efficiency, (2) reduced spectral baseline wiggles, and (3) software-based sideband separation. We developed an FMLO system for the Nobeyama 45-m telescope and a data reduction procedure for it. Frequency modulation was realized by a tunable and programmable first local oscillator. With observations of Galactic sources, we demonstrate that the observation efficiency of the FMLO method is dramatically improved compared to conventional switching methods. Specifically, we find that the time to achieve the same noise level is reduced by a factor of 3.0 in single-pointed observations and by a factor of 1.2 in mapping observations. The FMLO method can be applied to observations of fainter ($\sim$mK) spectral lines and larger ($\sim$deg$^{2}$) mapping. It would offer much more efficient and baseline-stable observations compared to conventional switching methods., 22 pages, 15 figures, 2 tables, accepted for publication in Publications of the Astronomical Society of Japan

An ultra-wideband, large field-of-view (sub)millimeter wave imaging spectrometer is imperative for uncovering the evolution of dust-enshrouded cosmic star formation rate, galaxy evolution, and structure formation, over cosmic time. Here we report the first on-sky demonstration of DESHIMA. DESHIMA (Deep Spectroscopic High-redshift Mapper) is a new type of submillimeter wave spectrometer, which uses a superconducting filterbank on a chip to achieve a very wide instantaneous bandwidth. Compared to an optical spectrometer with equivalent performance, such an on-chip spectrometer is not only compact, but also offers a higher degree of potential scalability to multiple spatial pixels. On the filterbank spectrometer chip of DESHIMA, the signal captured by the lens-antenna travels through a coplanar waveguide made of superconducting NbTiN, from which planar NbTiN bandpass filters branch out to divide the signal into frequency channels. At the output of each filter is a NbTiN/Al hybrid kinetic inductance detector (KID). These KIDs are operated at 120 mK with a 2-stage adiabatic demagnetization refrigerator (ADR), and their response is read out using the SpaceKIDs readout electronics. Being in its phase-1 configuration, DESHIMA currently covers the 330-370 GHz band with 49 spectral channels, offering a spectral resolution F/dF = 400, or dV = 700 km/s. This design is intended as a scalable prototype towards the phase-2 DESHIMA instrument, which targets at 240-720 GHz instantaneous band coverage with a resolution of F/dF = 500 (dV = 600 km/s), and >2 spatial pixels. In the laboratory, the sensitivity and frequency response of DESHIMA was characterized using a black-body calibration source and a THz photo-mixer source, respectively. The sensitivity is photon-noise limited at a detector loading power of ~1 pW, with a photon-noise limited optical Noise Equivalent Power of 1-2 x 10^-16 W Hz^-0.5. From October to November 2017, DESHIMA was installed on the Atacama Submillimeter Telescope Experiment (ASTE), a 10 m diameter antenna in the Atacama Desert of Chile. The sensitivity of DESHIMA measured inside the ASTE cabin is similar to lab results. At the time of submission of the abstract, DESHIMA has successfully detected multiple astronomical sources, in both continuum and line emission. At the conference we will report the lessons learned in the first actual operation of an on-chip filterbank spectrometer on a telescope, including the influence of thermal cycles on the filters, system susceptibility to telescope environment and motion, on-sky beam pattern, and sensitivity to continuum and line emission.

We present our ALMA Cycle 4 measurements of the [CII] emission line and the underlying far-infrared (FIR) continuum emission from four optically low-luminosity ($M_{\rm 1450} > -25$) quasars at $z \gtrsim 6$ discovered by the Subaru Hyper Suprime Cam (HSC) survey. The [CII] line and FIR continuum luminosities lie in the ranges $L_{\rm [CII]} = (3.8-10.2) \times 10^8~L_\odot$ and $L_{\rm FIR} = (1.2-2.0) \times 10^{11}~L_\odot$, which are at least one order of magnitude smaller than those of optically-luminous quasars at $z \gtrsim 6$. We estimate the star formation rates (SFR) of our targets as $\simeq 23-40~M_\odot ~{\rm yr}^{-1}$. Their line and continuum-emitting regions are marginally resolved, and found to be comparable in size to those of optically luminous quasars, indicating that their SFR or likely gas mass surface densities (key controlling parameter of mass accretion) are accordingly different. The $L_{\rm [CII]}/L_{\rm FIR}$ ratios of the hosts, $\simeq (2.2-8.7) \times 10^{-3}$, are fully consistent with local star-forming galaxies. Using the [CII] dynamics, we derived their dynamical masses within a radius of 1.5-2.5 kpc as $\simeq (1.4-8.2) \times 10^{10}~M_\odot$. By interpreting these masses as stellar ones, we suggest that these faint quasar hosts are on or even below the star-forming main sequence at $z \sim 6$, i.e., they appear to be transforming into quiescent galaxies. This is in contrast to the optically luminous quasars at those redshifts, which show starburst-like properties. Finally, we find that the ratios of black hole mass to host galaxy dynamical mass of the most of low-luminosity quasars including the HSC ones are consistent with the local value. The mass ratios of the HSC quasars can be reproduced by a semi-analytical model that assumes merger-induced black hole-host galaxy evolution., 20 pages, 9 figures, 4 tables. Accepted for publication in PASJ

In the central regions of active galaxies, dense molecular medium are exposed to various types of radiation and energy injections, such as UV, X-ray, cosmic ray, and shock dissipation. With the rapid progress of chemical models and implementation of new-generation mm/submm interferometry, we are now able to use molecules as powerful diagnostics of the physical and chemical processes in galaxies. Here we give a brief overview on the recent ALMA results to demonstrate how molecules can reveal underlying physical and chemical processes in galaxies. First, new detections of Galactic molecular absorption systems with elevated HCO/H$^{13}$CO$^+$ column density ratios are reported, indicating that these molecular media are irradiated by intense UV fields. Second, we discuss the spatial distributions of various types of shock tracers including HNCO, CH$_3$OH and SiO in NGC 253 and NGC 1068. Lastly, we provide an overview of proposed diagnostic methods of nuclear energy sources using ALMA, with an emphasis on the synergy with sensitive mid-infrared spectroscopy, which will be implemented by JWST and SPICA to disentangle the complex nature of heavily obscured galaxies across the cosmic time., Comment: 8 pages, 6 figures, to appear in the proceedings of IAU Symposium 315 "From Interstellar Clouds to Star-forming Galaxies: Universal Processes?", eds. P. Jablonka, P. Andre, and F.F.S. van der Tak

We report detections of two candidate distant submillimeter galaxies (SMGs), MM J154506.4$-$344318 and MM J154132.7$-$350320, which are discovered in the AzTEC/ASTE 1.1 mm survey toward the Lupus-I star-forming region. The two objects have 1.1 mm flux densities of 43.9 and 27.1 mJy, and have Herschel/SPIRE counterparts as well. The Submillimeter Array counterpart to the former SMG is identified at 890 $��$m and 1.3 mm. Photometric redshift estimates using all available data from the mid-infrared to the radio suggest that the redshifts of the two SMGs are $z_{\rm photo} \simeq$ 4-5 and 3, respectively. Near-infrared objects are found very close to the SMGs and they are consistent with low-$z$ ellipticals, suggesting that the high apparent luminosities can be attributed to gravitational magnification. The cumulative number counts at $S_{\rm 1.1mm} \ge 25$ mJy, combined with other two 1.1-mm brightest sources, are $0.70 ^{+0.56}_{-0.34}$ deg$^{-2}$, which is consistent with a model prediction that accounts for flux magnification due to strong gravitational lensing. Unexpectedly, a $z > 3$ SMG and a Galactic dense starless core (e.g., a first hydrostatic core) could be similar in the mid-infrared to millimeter spectral energy distributions and spatial structures at least at $\gtrsim 1"$. This indicates that it is necessary to distinguish the two possibilities by means of broad band photometry from the optical to centimeter and spectroscopy to determine the redshift, when a compact object is identified toward Galactic star-forming regions., Accepted for publication in ApJ. 16 pages, 9 figures, 2 tables

We present $1''.4$ (98 pc) resolution ALMA observations of $^{13}$CO($J$=1-0), C$^{18}$O($J$=1-0), CS($J$=2-1) and CH$_3$OH($J_K$=$2_K$-$1_K$) molecular lines in the central $1'$ (4.2 kpc) region of NGC 1068 to study the physical and chemical properties of giant molecular clouds (GMCs) and to test whether these GMC-scale properties are linked to the larger-scale galactic environment. Using the derived $^{13}$CO cube, we have identified 187 high-significance ($> 8\sigma$) GMCs by employing the CLUMPFIND algorithm. The molecular gas masses of GMCs $M_{\rm ^{13}CO}$, derived from the $^{13}$CO data, range from $1.8 \times 10^4 ~ M_\odot$ to $4.2 \times 10^7 ~M_\odot$. A mass function of GMCs in NGC 1068 has been obtained for the first time at $\sim$100 pc resolution. We find the slope of the mass function $\gamma = -1.25 \pm 0.07$ for a mass range of $M_{\rm ^{13}CO} \geq 10^5M_\odot$. This is shallower than the GMCs in the disk regions of the Milky Way, M51 and NGC 300. Further, we find that the high mass cut-off of the GMC mass function occurs at $M_{\rm ^{13}CO} \sim 6 \times 10^7 M_\odot$, which is an order of magnitude larger than that in the nuclear bar region of M51, indicating that the more massive clouds dominate the mass budget in NGC 1068. The observed C$^{18}$O)/$^{13}$CO intensity ratios are found to be fairly uniform (0.27 $\pm$ 0.05) among the identified GMCs. In contrast, the CH$_3$OH/$^{13}$CO ratios exhibit striking spatial variation across the disk, with the smallest values around the bar-end ($, Comment: 35 pages, 13 figures, in press at Publ. Astron. Soc. Japan

We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species ($^{13}$CO and C$^{18}$O) $\it{J}$ = 3--2, CN $\it{N}$ = 3--2 and CS $\it{J}$ = 7--6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of $\sim$1.$^{\prime\prime}$3 $\times$ 1.$^{\prime\prime}$2. The physical properties of these molecules and shock-related molecules such as HNCO, CH$_{3}$CN, SO, and CH$_{3}$OH detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14--22 K and upper limits of 20--40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ring, those of the shock-related molecules are enhanced by a factor of 3--10 in the CND. We also discuss the chemistry of each species, and compare the fractional abundances in the CND and starburst ring with those of Galactic sources such as cold cores, hot cores, and shocked molecular clouds in order to study the overall characteristics. We find that the abundances of shock-related molecules are more similar to abundances in hot cores and/or shocked clouds than to cold cores. The CND hosts relatively complex molecules, which are often associated with shocked molecular clouds or hot cores. Because a high X-ray flux can dissociate these molecules, they must also reside in regions shielded from X-rays., 26 pages, 3 figures, Accepted for publication in PASJ

Sensitive observations with ALMA allow astronomers to observe the detailed distributions of molecules with relatively weak intensity in nearby galaxies. In particular, we report distributions of several molecular transitions including shock and dust related species ($^{13}$CO $J$ = 1--0, C$^{18}$O $J$ = 1--0, $^{13}$CN $N$ = 1--0, CS $J$ = 2--1, SO $J_N$ = 3$_2$--2$_1$, HNCO $J_{Ka,Kc}$ = 5$_{0,5}$--4$_{0,4}$, HC$_3$N $J$ = 11--10, 12--11, CH$_3$OH $J_K$ = 2$_K$--1$_K$, and CH$_3$CN $J_K$ = 6$_K$--5$_K$) in the nearby Seyfert 2 galaxy NGC 1068 observed with the ALMA early science program. The central $\sim$1 arcmin ($\sim$4.3 kpc) of this galaxy was observed in the 100 GHz region covering $\sim$96--100 GHz and $\sim$108--111 GHz with an angular resolution of $\sim4"\times2"$ (290 pc$\times$140 pc) to study the effects of an active galactic nucleus and its surrounding starburst ring on molecular abundances. Here, we present images and report a classification of molecular distributions into three main categories: (1) Molecules concentrated in the circumnuclear disk (CND) (SO $J_N$ = 3$_2$--2$_1$, HC$_3$N $J$ = 11--10, 12--11, and CH$_3$CN $J_K$ = 6$_K$--5$_K$), (2) Molecules distributed both in the CND and the starburst ring (CS $J$ = 2--1 and CH$_3$OH $J_K$ = 2$_K$--1$_K$), (3) Molecules distributed mainly in the starburst ring ($^{13}$CO $J$ = 1--0 and C$^{18}$O $J$ = 1--0). Since most of the molecules such as HC$_3$N observed in the CND are easily dissociated by UV photons and X-rays, our results indicate that these molecules must be effectively shielded. In the starburst ring, the relative intensity of methanol at each clumpy region is not consistent with those of $^{13}$CO, C$^{18}$O, and CS. This difference is probably caused by the unique formation and destruction mechanisms of CH$_3$OH., 21 pages, 4 figures, accepted for publication to PASJ

医療用線源輸送容器, および大線源輸送容器について, ―50℃の低温環境条件における試験を行った。これらの試験体は, すでに9m落下試験, 1m落下試験, 800℃, 30分の耐火試験を行ったものである。結果は, いずれも容器に損傷はみられず, 試験体内に収納したダミー線源カプセルに変化はなく, また漏洩放射線量率も, 試験後において, 試験前の2倍をこえることもなく, BU型輸送物の試験後の規準値の258μC/kg (1000mR) /hよりきわめて低かった。ゆえに, これらの試験体は―40℃, 1週間の環境条件に十分耐えることがわかった。なお, 本報告の一部は, 日本放射線機器工業会会報No.49に発表されたものである。

We present a conceptual study of a large format imaging spectrograph for the Large Submillimeter Telescope (LST) and the Atacama Large Aperture Submillimeter Telescope (AtLAST). Recent observations of high-redshift galaxies indicate the onset of earliest star formation just a few 100 million years after the Big Bang (i.e., z = 12--15), and LST/AtLAST will provide a unique pathway to uncover spectroscopically-identified first forming galaxies in the pre-reionization era, once it will be equipped with a large format imaging spectrograph. We propose a 3-band (200, 255, and 350 GHz), medium resolution (R = 2,000) imaging spectrograph with 1.5 M detectors in total based on the KATANA concept (Karatsu et al. 2019), which exploits technologies of the integrated superconducting spectrometer (ISS) and a large-format imaging array. A 1-deg2 drilling survey (3,500 hr) will capture a large number of [O III] 88 um (and [C II] 158 um) emitters at z = 8--9, and constrain [O III] luminosity functions at z > 12., Presented at SPIE Astronomical Telescopes + Instrumentation 2020. Full published paper and video available at http://dx.doi.org/10.1117/12.2561238 See also https://www.lstobservatory.org for the LST project