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The SPIRE FTS Spectral Feature Finder (FF), developed within the Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument team, is an automated spectral feature fitting routine that attempts to find significant features in SPIRE FTS spectra. The $^3$P$_1$ - $^3$P$_0$ and $^3$P$_2$ - $^3$P$_1$ neutral carbon fine structure lines are common features in carbon rich far-infrared astrophysical sources. These features can be difficult to detect using an automated feature detection routine due to their typically low amplitude and line blending. In this paper we describe and validate the FF sub-routine designed to detect the neutral carbon emission observed in SPIRE spectral data., 8 pages, 9 figures, 2 tables, final version accepted by MNRAS June 2020

This paper presents the results of a comprehensive analysis of Spire Global, Inc.’s total electron content (TEC) observations using NorthWest Research Associate’s (NWRA) assimilative ionospheric model GPSII. A week’s worth of TEC data was collected from Spire’s constellation of low-Earth orbiting micro-satellites carrying GNSS receivers and assimilated into GPSII. GPSII operation with the data was evaluated and the results were validated with observations from independent sources. Ground-based ionosondes were employed in diagnosing the accuracy of the derived models; NWRA studied the differences between the F2 peak parameters ($f_{0}F_{2}$ and $H_{m}F_{2}$) derived from ionograms and those computed with GPSII. The analysis showed that Spire’s TEC data was both compatible for ingestion into GPSII and that the assimilation of the data improved the comparison to ground-based ionosondes. On average $f_{0}F_{2}$ was improved by 1.317 MHz and $H_{m}F_{2}$ was improved by 22.8 km with this data ingested into GPSII.

Wide-field sub-millimetre surveys have driven many major advances in galaxy evolution in the past decade, but without extensive follow-up observations the coarse angular resolution of these surveys limits the science exploitation. This has driven the development of various analytical deconvolution methods. In the last half a decade Generative Adversarial Networks have been used to attempt deconvolutions on optical data. Here we present an autoencoder with a novel loss function to overcome this problem in the sub-millimeter wavelength range. This approach is successfully demonstrated on Herschel SPIRE 500$\mu$m COSMOS data, with the super-resolving target being the JCMT SCUBA-2 450$\mu$m observations of the same field. We reproduce the JCMT SCUBA-2 images with high fidelity using this autoencoder. This is quantified through the point source fluxes and positions, the completeness and the purity., Comment: Published by MNRAS in Volume 507 issue 1 October 2021, 12 pages, 7 figures. https://doi.org/10.1093/mnras/stab2195

Author(s): Kim, Seong Jin; Oi, Nagisa; Goto, Tomotsugu; Ikeda, Hiroyuki; Ho, Simon C-C; Shim, Hyunjin; Toba, Yoshiki; Hwang, Ho Seong; Hashimoto, Tetsuya; Barrufet, Laia; Malkan, Matthew; Kim, Helen K; Huang, Ting-Chi; Matsuhara, Hideo; Miyaji, Takamitsu; Pearson, Chris; Serjeant, Stephen; Santos, Daryl Joe D; Kim, Eunbin; Pollo, Agnieszka; Jeong, Woong-Seob; Wang, Ting-Wen; Momose, Rieko; Takagi, Toshinobu | Abstract: ABSTRACT The North Ecliptic Pole field is a natural deep-field location for many satellite observations. It has been targeted many times since it was surveyed by the AKARI space telescope with its unique wavelength coverage from the near- to mid-infrared (mid-IR). Many follow-up observations have been carried out, making this field one of the most frequently observed areas with a variety of facilities, accumulating abundant panchromatic data from the X-ray to the radio wavelength range. Recently, a deep optical survey with the Hyper Suprime-Cam (HSC) at the Subaru telescope covered the NEP-Wide (NEPW) field, which enabled us to identify faint sources in the near- and mid-IR bands, and to improve the photometric redshift (photo-z) estimation. In this work, we present newly identified AKARI sources by the HSC survey, along with multiband photometry for 91 861 AKARI sources observed over the NEPW field. We release a new band-merged catalogue combining various photometric data from the GALEX UV to submillimetre (sub-mm) bands (e.g. Herschel/SPIRE, JCMT/SCUBA-2). About ∼20 000 AKARI sources are newly matched to the HSC data, most of which seem to be faint galaxies in the near- to mid-infrared AKARI bands. This catalogue is motivating a variety of current research, and will be increasingly useful as recently launched (eROSITA/ART-XC) and future space missions (such as JWST, Euclid, and SPHEREx) plan to take deep observations in the NEP field.

Herschel/SPIRE observations of Uranus are used to search for stratospheric hydrogen chloride (HCl) emission at 41.74 cm$^{-1}$. HCl was not detected and instead 3$\sigma$ upper limits were determined; $, Comment: 4 pages, 1 figure, accepted for publication in RNAAS 2020

The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated spectral feature fitting routine developed within the SPIRE instrument team to extract all prominent spectral features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the spectral features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 spectral lines associated with missing features from SPIRE FTS observations are added to the FF catalogue., 15 pages (+2 appendix pages), 14 figures, 7 tables, final version accepted by MNRAS June 2020

The lower altitude region of the ionosphere (60-150 km) is characterized by a strong coupling between the neutral atmosphere and ionospheric plasma. Due to the high ion-neutral collision rate the plasma at these altitudes is less constrained to follow the magnetic field lines compared to plasma at higher altitudes in the ionosphere. This both permits the development of the windshear mechanism responsible for the formation of sporadic E (Es) layers and affects the coupling between atmospheric gravity waves (AGWs) and the ionospheric plasma. AGWs transport energy from the lower atmosphere upward to higher altitudes. The wave amplitudes increase with altitude and eventually couple to the ionospheric plasma generating electron density perturbations or travelling ionospheric disturbances (TIDs). Es layers are high-density, narrow-altitude layers of enhanced electron density in the ionosphere’s E region. Contrary to what the name would suggest, Es occurs relatively frequently and its climatology has been characterised through ionosonde studies. Furthermore, the vertical structure of Es has been studied using sounding rockets. However, such measurements are very sparse and cannot be used to routine monitoring or for detecting the Es occurrence at a particular time and location. Monitoring AGW and Es layers is of great interest to many terrestrial applications, such as natural hazard warning systems, radio communications, and global navigation satellite system (GNSS) users. Recently, the coupling between Es layers and AGWs has also seen increased research attention. Spire operates a large constellation of 3U cubesats which carry a radio occultation (RO) GNSS receiver. For ionospheric studies, the satellites measure Total Electron Content (TEC) data in both zenith-looking and RO geometries using dual frequency observations. Furthermore, the high rate (50Hz) phase measurements that are generally used for neutral atmosphere RO can also be used to produce relative TEC profiles of the lower ionosphere with high vertical resolution (approximately 100m at E region altitudes). In this talk, we review recent results describing the coverage and quality of E region ionospheric measurements collected by Spire. Furthermore, we describe Spire's Es and AGW automated detection algorithm that is based on a Hilbert–Huang transform (HHT) of the relative TEC profiles and we compare our results with time coincident and co-located ionosonde data. We also look toward the future and describe how low cost cubesat constellations can be used for global monitoring of AGWs and Es layers. These first results also open the way to near real-time monitoring and classification of more general ionospheric anomalies

The Herschel SPIRE FTS Spectral Feature Finder (FF) detects significant spectral features within SPIRE spectra and employs two routines, and external references, to estimate source radial velocity. The first routine is based on the identification of rotational CO emission, the second cross-correlates detected features with a line template containing most of the characteristic lines in typical far infra-red observations. In this paper, we outline and validate these routines, summarise the results as they pertain to the FF, and comment on how external references were incorporated., Comment: 12 pages, 16 figures, 1 table, accepted by MNRAS March 2020

We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant spectral features from SPIRE FTS data products. Optimising the number of features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive., Comment: 20 pages, 8 figures, 8 tables, final version accepted by MNRAS June 2020

The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated spectral feature fitting routine developed within the SPIRE instrument team to extract all prominent spectral features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of N ii and C i gas at far-infrared frequencies in complement to radio observations of the [H i] 21-cm line and the CO(1-0) transition as well as optical measurements of Hα. We find that measurements of both N ii and C i gas follow a similar velocity profile to that of H i and Hα showing a correlation between neutral and ionized regions of the interstellar medium in the disc of NGC 891.

IRAS 20319+3958 in Cygnus X South is a rare example of a free-floating globule (mass ~240 Msun, length ~1.5 pc) with an internal HII region created by the stellar feedback of embedded intermediate-mass stars, in particular, one Herbig Be star. Here, we present a Herschel/HIFI CII 158 mu map of the whole globule and a large set of other FIR lines (mid-to high-J CO lines observed with Herschel/PACS and SPIRE, the OI 63 mu line and the CO 16-15 line observed with upGREAT on SOFIA), covering the globule head and partly a position in the tail. The CII map revealed that the whole globule is probably rotating. Highly collimated, high-velocity CII emission is detected close to the Herbig Be star. We performed a PDR analysis using the KOSMA-tau PDR code for one position in the head and one in the tail. The observed FIR lines in the head can be reproduced with a two-component model: an extended, non-clumpy outer PDR shell and a clumpy, dense, and thin inner PDR layer, representing the interface between the HII region cavity and the external PDR. The modelled internal UV field of ~2500 Go is similar to what we obtained from the Herschel FIR fluxes, but lower than what we estimated from the census of the embedded stars. External illumination from the ~30 pc distant Cyg OB2 cluster, producing an UV field of ~150-600 G0 as an upper limit, is responsible for most of the CII emission. For the tail, we modelled the emission with a non-clumpy component, exposed to a UV-field of around 140 Go., accepted by Astronomy & Astrophysics

著者人数: 12名, Accepted: 2018-11-02, 資料番号: SA1180285000

Aims: To constrain models of high-mass star formation it is important to identify the massive dense cores (MDCs) that are able to form high-mass star(s). This is one of the purposes of the Herschel/HOBYS key programme. Here, we carry out the census and characterise of the properties of the MDCs population of the NGC 6357 H II region. Methods: Our study is based on the Herschel/PACS and SPIRE 70-500 μm images of NGC 6357 complemented with (sub-)millimetre and mid-infrared data. We followed the procedure established by the Herschel/HOBYS consortium to extract ~0.1 pc massive dense cores using the getsources software. We estimated their physical parameters (temperatures, masses, luminosities) from spectral energy distribution (SED) fitting. Results: We obtain a complete census of 23 massive dense cores, amongst which one is found to be IR-quiet and twelve are starless, representing very early stages of the star-formation process. Focussing on the starless MDCs, we have considered their evolutionary status, and suggest that only five of them are likely to form a high-mass star. Conclusions: We find that, contrarily to the case in NGC 6334, the NGC 6357 region does not exhibit any ridge or hub features that are believed to be crucial to the massive star formation process. This study adds support for an empirical model in which massive dense cores and protostars simultaneously accrete mass from the surrounding filaments. In addition, the massive star formation in NGC 6357 seems to have stopped and the hottest stars in Pismis 24 have disrupted the filaments. Full Table C1, Tables C2-C5, the reduced Herschel FITS images and the column density FITS image are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A134 Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

We present high-resolution, high-cadence observations of six, fine-scale, on-disk jet-like events observed by the High-resolution Coronal Imager 2.1 (Hi-C 2.1) during its sounding-rocket flight. We combine the Hi-C 2.1 images with images from SDO/AIA, and IRIS, and investigate each event's magnetic setting with co-aligned line-of-sight magnetograms from SDO/HMI. We find that: (i) all six events are jetlet-like (having apparent properties of jetlets), (ii) all six are rooted at edges of magnetic network lanes, (iii) four of the jetlet-like events stem from sites of flux cancelation between majority-polarity network flux and merging minority-polarity flux, and (iv) four of the jetlet-like events show brightenings at their bases reminiscent of the base brightenings in coronal jets. The average spire length of the six jetlet-like events (9,000$\pm$3000km) is three times shorter than that for IRIS jetlets (27,000$\pm$8000km). While not ruling out other generation mechanisms, the observations suggest that at least four of these events may be miniature versions of both larger-scale coronal jets that are driven by minifilament eruptions and still-larger-scale solar eruptions that are driven by filament eruptions. Therefore, we propose that our Hi-C events are driven by the eruption of a tiny sheared-field flux rope, and that the flux-rope field is built and triggered to erupt by flux cancelation., 10 pages, 5 figures, 1 Table, accepted for publication in ApJ Letters

We present a WFC3 F160W ($H$-band) selected catalog in the CANDELS/GOODS-N field containing photometry from the ultraviolet (UV) to the far-infrared (IR), photometric redshifts and stellar parameters derived from the analysis of the multi-wavelength data. The catalog contains 35,445 sources over the 171 arcmin$^{2}$ of the CANDELS F160W mosaic. The 5$\sigma$ detection limits (within an aperture of radius 0\farcs17) of the mosaic range between $H=27.8$, 28.2 and 28.7 in the wide, intermediate and deep regions, that span approximately 50\%, 15\% and 35\% of the total area. The multi-wavelength photometry includes broad-band data from UV (U band from KPNO and LBC), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), near-to-mid IR (HST/WFC3 F105W, F125W, F140W and F160W, Subaru/MOIRCS Ks, CFHT/Megacam K, and \spitzer/IRAC 3.6, 4.5, 5.8, 8.0 $\mu$m) and far IR (\spitzer/MIPS 24$\mu$m, HERSCHEL/PACS 100 and 160$\mu$m, SPIRE 250, 350 and 500$\mu$m) observations. In addition, the catalog also includes optical medium-band data (R$\sim50$) in 25 consecutive bands, $\lambda=500$ to 950~nm, from the SHARDS survey and WFC3 IR spectroscopic observations with the G102 and G141 grisms (R$\sim210$ and 130). The use of higher spectral resolution data to estimate photometric redshifts provides very high, and nearly uniform, precision from $z=0-2.5$. The comparison to 1,485 good quality spectroscopic redshifts up to $z\sim3$ yields $\Delta z$/(1+$z_{\rm spec}$)$=$0.0032 and an outlier fraction of $\eta=$4.3\%. In addition to the multi-band photometry, we release added-value catalogs with emission line fluxes, stellar masses, dust attenuations, UV- and IR- based star formation rates and rest-frame colors., Comment: The catalogs, images and spectra are available in Rainbow-slicer (https://bit.ly/2OxKKx1 ), navigator (https://bit.ly/2GDS180 ) and MAST (https://bit.ly/2YtoBQ4 ). In addition to the photometry and other added-value catalogs we release UV+IR star formation rates based on Spitzer (MIPS) and Herschel (PACS and SPIRE) in the 5 CANDELS fields

The SPIRE Fourier Transform Spectrometer on board the Herschel Space Observatory had two standard spectral resolution modes for science observations: high resolution (HR) and low resolution (LR), which could also be performed in sequence (H+LR). A comparison of the HR and LR resolution spectra taken in this sequential mode, revealed a systematic discrepancy in the continuum level. Analysing the data at different stages during standard pipeline processing, demonstrates the telescope and instrument emission affect HR and H+LR observations in a systematically different way. The origin of this difference is found to lie in the variation of both the telescope and instrument response functions, while it is triggered by fast variation of the instrument temperatures. As it is not possible to trace the evolution of the response functions through auxiliary housekeeping parameters, the calibration cannot be corrected analytically. Therefore an empirical correction for LR spectra has been developed, which removes the systematic noise introduced by the variation of the response functions., 13 pages, 17 figures, 4 tables. Accepted for publication in MNRAS

We combine Herschel/SPIRE sub-millimeter (submm) observations with existing multi-wavelength data to investigate the characteristics of low redshift, optically red galaxies detected in submm bands. We select a sample of galaxies in the redshift range 0.01$\leq$z$\leq$0.2, having >5$\sigma$ detections in the SPIRE 250 micron submm waveband. Sources are then divided into two sub-samples of $red$ and $blue$ galaxies, based on their UV-optical colours. Galaxies in the $red$ sample account for $\approx$4.2 per cent of the total number of sources with stellar masses M$_{*}\gtrsim$10$^{10}$ Solar-mass. Following visual classification of the $red$ galaxies, we find that $\gtrsim$30 per cent of them are early-type galaxies and $\gtrsim$40 per cent are spirals. The colour of the $red$-spiral galaxies could be the result of their highly inclined orientation and/or a strong contribution of the old stellar population. It is found that irrespective of their morphological types, $red$ and $blue$ sources occupy environments with more or less similar densities (i.e., the $\Sigma_5$ parameter). From the analysis of the spectral energy distributions (SEDs) of galaxies in our samples based on MAGPHYS, we find that galaxies in the $red$ sample (of any morphological type) have dust masses similar to those in the $blue$ sample (i.e. normal spiral/star-forming systems). However, in comparison to the $red$-spirals and in particular $blue$ systems, $red$-ellipticals have lower mean dust-to-stellar mass ratios. Besides galaxies in the $red$-elliptical sample have much lower mean star-formation/specific-star-formation rates in contrast to their counterparts in the $blue$ sample. Our results support a scenario where dust in early-type systems is likely to be of an external origin., Comment: Accepted for publication in MNRAS - Paper without gallery of galaxy post-stamp images (in appendix). Full paper with appendix is available here: http://www.ast.cam.ac.uk/~adariush/hatlas_alidariush_20151125.pdf

We present ALMA Atacama Compact Array (ACA) 870 micron continuum maps of 28 infrared-bright SDSS quasars with Herschel/SPIRE detections at redshifts 2-4, the largest such sample ever observed with ALMA. The ACA detections are centred on the SDSS coordinates to within 1 arcsec for about 80 per cent of the sample. Larger offsets indicate that the far-infrared (FIR) emission detected by Herschel might come from a companion source. The majority of the objects (about 70 per cent) have unique ACA counterparts within the SPIRE beam down to 3-4 arcsec resolution. Only 30 per cent of the sample shows clear evidence for multiple sources with secondary counterparts contributing to the total 870 micron flux within the SPIRE beam to at least 25 per cent. We discuss the limitations of the data based on simulated pairs of point-like sources at the resolution of the ACA and present an extensive comparison of our findings with recent works on the multiplicities of sub-millimetre galaxies. We conclude that, despite the coarse resolution of the ACA, our data support the idea that, for a large fraction of FIR-bright quasars, the sub-mm emission comes from single sources. Our results suggest that, on average, optically bright quasars with strong FIR emission are not triggered by early-stage mergers but are, instead, together with their associated star formation rates, the outcome of either late-stage mergers or secular processes., 16 pages, 10 figures

A brief overview of the Herschel Space Telescope PACS and SPIRE spectrographs is given, pointing out aspects of working with the data products that should be considered by anyone using them. Some preliminary results of Planetary Nebulae (PNe) taken from the Herschel Planetary Nebula Survey (HerPlaNs) programme are then used to demonstrate what can be done with spectroscopy observations made with PACS. The take-home message is that using the full 3D information that PACS spectroscopy observations give will greatly aid in the interpretation of PNe.

$\mathit{Herschel}$ extragalactic surveys offer a unique opportunity to efficiently select a significant number of rare and massive dusty objects, and thus gain insight into the prodigious star-forming activity that takes place in the very distant Universe. To search for $z\geq4$ dusty star-forming galaxies, in this work we consider red SPIRE objects with fluxes rising from 250 $\mu$m to $500\:\mu$m (so-called "500 $\mu$m-risers"). We aim to implement a novel method to obtain a statistical sample of "500 $\mu$m-risers" and fully evaluate our selection inspecting different models of galaxy evolution. We consider one of the largest and deepest ${\it Herschel}$ surveys, the Herschel Virgo Cluster Survey. We develop a novel selection algorithm which links the source extraction and spectral energy distribution fitting. We select 133 "500 $\mu$m-risers" over 55 deg$^{2}$, imposing the criteria: $S_{500}>S_{350}>S_{250}$, $S_{250}>13.2$ mJy and $S_{500}>$30 mJy. Differential number counts are in a fairly good agreement with models, displaying better match than other existing samples. In order to interpret the statistical properties of selected sources, which has been proven as a very challenging task due the complexity of observed artefacts, we make end-to-end simulations including physical clustering and lensing. The estimated fraction of strongly lensed sources is $24^{+6}_{-5}\%$ based on models. We present the faintest known statistical sample of "500 $\mu$m-risers" and show that noise and strong lensing have crucial impact on measured counts and redshift distribution of selected sources. We estimate the flux-corrected star formation rate density at $44$ sources., Comment: 28 pages, 13 figures, version accepted for publication in A&A

We present full spectral scans from 200-670$��$m of 26 Class 0+I protostellar sources, obtained with $Herschel$-SPIRE, as part of the "COPS-SPIRE" Open Time program, complementary to the DIGIT and WISH Key programs. Based on our nearly continuous, line-free spectra from 200-670 $��$m, the calculated bolometric luminosities ($L_{\rm bol}$) increase by 50% on average, and the bolometric temperatures ($T_{\rm bol}$) decrease by 10% on average, in comparison with the measurements without Herschel. Fifteen protostars have the same Class using $T_{\rm bol}$ and $L_{\rm bol}$/$L_{\rm submm}$. We identify rotational transitions of CO lines from J=4-3 to J=13-12, along with emission lines of $^{13}$CO, HCO$^+$, H$_{2}$O, and [CI]. The ratios of $^{12}$CO to $^{13}$CO indicate that $^{12}$CO emission remains optically thick for $J_{\rm up}$ < 13. We fit up to four components of temperature from the rotational diagram with flexible break points to separate the components. The distribution of rotational temperatures shows a primary population around 100 K with a secondary population at $\sim$350 K. We quantify the correlations of each line pair found in our dataset, and find the strength of correlation of CO lines decreases as the difference between $J$-level between two CO lines increases. The multiple origins of CO emission previously revealed by velocity-resolved profiles are consistent with this smooth distribution if each physical component contributes to a wide range of CO lines with significant overlap in the CO ladder. We investigate the spatial extent of CO emission and find that the morphology is more centrally peaked and less bipolar at high-$J$ lines. We find the CO emission observed with SPIRE related to outflows, which consists two components, the entrained gas and shocked gas, as revealed by our rotational diagram analysis as well as the studies with velocity-resolved CO emission., 50 pages, 18 figures, accepted to ApJS. Revised for Table 6 and Figure 4

We present intensity-corrected Herschel maps at 100 um, 160 um, 250 um, 350 um, and 500 um for 56 isolated low-mass clouds. We determine the zero-point corrections for Herschel PACS and SPIRE maps from the Herschel Science Archive (HSA) using Planck data. Since these HSA maps are small, we cannot correct them using typical methods. Here, we introduce a technique to measure the zero-point corrections for small Herschel maps. We use radial profiles to identify offsets between the observed HSA intensities and the expected intensities from Planck. Most clouds have reliable offset measurements with this technique. In addition, we find that roughly half of the clouds have underestimated HSA-SPIRE intensities in their outer envelopes relative to Planck, even though the HSA-SPIRE maps were previously zero-point corrected. Using our technique, we produce corrected Herschel intensity maps for all 56 clouds and determine their line-of-sight average dust temperatures and optical depths from modified black body fits. The clouds have typical temperatures of ~ 14-20 K and optical depths of ~ 1e-5 - 1e-3. Across the whole sample, we find an anti-correlation between temperature and optical depth. We also find lower temperatures than what was measured in previous Herschel studies, which subtracted out a background level from their intensity maps to circumvent the zero-point correction. Accurate Herschel observations of clouds are key to obtain accurate density and temperature profiles. To make such future analyses possible, intensity-corrected maps for all 56 clouds are publicly available in the electronic version., Accepted to ApJ, 35 pages, 15 figures, 4 Tables. Intensity-corrected FITS images and temperature/optical depths maps are available with the electronic version

We present 850 and 450 micron observations of the dense regions within the Auriga-California molecular cloud using SCUBA-2 as part of the JCMT Gould Belt Legacy Survey to identify candidate protostellar objects, measure the masses of their circumstellar material (disk and envelope), and compare the star formation to that in the Orion A molecular cloud. We identify 59 candidate protostars based on the presence of compact submillimeter emission, complementing these observations with existing Herschel/SPIRE maps. Of our candidate protostars, 24 are associated with young stellar objects (YSOs) in the Spitzer and Herschel/PACS catalogs of 166 and 60 YSOs, respectively (177 unique), confirming their protostellar nature. The remaining 35 candidate protostars are in regions, particularly around LkHalpha 101, where the background cloud emission is too bright to verify or rule out the presence of the compact 70 micron emission that is expected for a protostellar source. We keep these candidate protostars in our sample but note that they may indeed be prestellar in nature. Our observations are sensitive to the high end of the mass distribution in Auriga-Cal. We find that the disparity between the richness of infrared star forming objects in Orion A and the sparsity in Auriga-Cal extends to the submillimeter, suggesting that the relative star formation rates have not varied over the Class II lifetime and that Auriga-Cal will maintain a lower star formation efficiency., Comment: 39 pages (54 including the Appendix), 9 figures, 3 tables, in press in ApJ

The bipolar nebula Menzel 3 (Mz 3) was observed as part of the \textit{Herschel} Planetary Nebula Survey (\textit{HerPlaNS}), which used the PACS and SPIRE instruments aboard the \textit{Herschel Space Observatory} to study a sample of planetary nebulae (PNe). In this paper, one of the series describing \textit{HerPlaNS} results, we report the detection of H I recombination lines (HRLs) in the spectrum of Mz 3. Inspection of the spectrum reveals the presence of 12 HRLs in the 55 to 680 $\mu$m range covered by the PACS and SPIRE instruments (H11$\alpha$ to H21$\alpha$ and H14$\beta$). The presence of HRLs in this range is unusual for PNe and has not been reported in Mz 3 before. Our analysis indicates that the HRLs we observed are enhanced by laser effect occurring in the core of Mz 3. Our arguments for this are: (i) the available Mz 3 optical to submillimetre HRL $\alpha$ line intensity ratios are not well reproduced by the spontaneous emission of optically thin ionized gas, as would be typical for nebular gas in PNe; (ii) the compact core of Mz 3 is responsible for a large fraction of the Herschel HRLs emission; (iii) the line intensity ratios for Mz 3 are very similar to those in the core emission of the well known star MWC 349A, where laser effect is responsible for the enhancement of HRLs in the Herschel wavelength range; (iv) the physical characteristics relevant to cause laser effect in the core of MWC 349A are very similar to those in the core of Mz 3., Comment: Published in MNRAS. ESA Portal Story. 13 Pages, 7 figures

The Comic Microwave Background satellite Planck with its High Frequency Instrument has surveyed the mm/sub-mm sky in six frequency channels from 100 to 900 GHz. A sample of 228 cold sources of the Cosmic Infrared Background was observed in follow-up with Herschel SPIRE. The majority of sources appear to be over-densities of star-forming galaxies matching the size of high-z proto-cluster regions, while a 3% fraction are individual bright, lensed galaxies. A large observing program is underway with the aim of resolving the regions into the constituent members of the Planck sources. First ALMA data have been received on one Planck/Herschel proto-cluster candidate, showing the expected large over-abundance of bright mm/sub-mm sources within the cluster region. ALMA long baseline data of the brightest lensed galaxy in the sample with > 1 Jy at 350 μm are also forthcoming.

Herschel[1] was a spatial submillimetre observatory with spectroscopic and imaging capabilities covering the range from 55 to 671 μm (0.44 to 5.5 THz) partly explored for the first time here. With a primary mirror of 3.28 m (effective diameter) and a surface accuracy better than 6 μm, it will remain the largest telescope launched until the arrival of the James Webb Space Telescope end of 2018. The observatory was equipped with a dewar that contained 2367 liters of liquid Helium at launch in May 2009. Positioned at the 2nd Lagrangian point, it functioned till April 2013. The telescope was passively cooled to 85 K. The total weight of the spacecraft was 3.4 tons at launch, including 315 kg for the mirror, 426 kg for the instruments and 335 kg of He. The payload was made of 3 instruments, 2 spectro-photometric cameras PACS [2] and SPIRE[3] equipped with bolometer arrays, and 1 heterodyne instrument, HIFI[4].

We have conducted two-component, non-LTE modeling of the CO lines from J = 1-0 through J = 13-12 in 87 galaxies observed by the Herschel SPIRE Fourier Transform Spectrometer (FTS). We find the average pressure of the cold molecular gas, traced especially by CO J = 1-0, is $\sim 10^{5.0 \pm 0.5}$ K cm$^{-3}$. The mid- to high-J lines of CO trace higher-pressure gas at $10^{6.5 \pm 0.6}$ K cm$^{-3}$; this pressure is slightly correlated with LFIR. Two components are often necessary to accurately fit the Spectral Line Energy Distributions (SLEDs); a one-component fit often underestimates the flux of CO J = 1-0 and the mass. If low-J lines are not included, mass is underestimated by an order of magnitude. Even when modeling the low-J lines alone or using an $\alpha_{CO}$ conversion factor, the mass should be considered to be uncertain to a factor of at least 0.4 dex, and the vast majority of the CO luminosity will be missed (median, 65%). We find a very large spread in our derived values of $\alpha_{CO}$, though they do not have a discernible trend with LFIR; the best fit is a constant 0.7 M$_{\odot}$/ (K kms$^{-1}$ pc$^2$), with a standard deviation of 0.36 dex, and a range of 0.3-1.6 M$_{\odot}$/ (K kms$^{-1}$ pc$^2$). We find average molecular gas depletion times ($\tau_{dep}$) of $10^8$ yr that decrease with increasing SFR. Finally, we note that the J = 11-10/J = 1-0 line flux ratio is diagnostic of the warm component pressure, and discuss the implications of this comprehensive study of SPIRE FTS extragalactic spectra for future study post-Herschel., Comment: 18 pages, additional figures available online. Accepted to MNRAS

By determining the nature of all the Planck compact sources within 808.4 deg^2 of large Herschel surveys, we have identified 27 candidate proto-clusters of dusty star forming galaxies (DSFGs) that are at least 3�� overdense in either 250, 350 or 500 $��$mm sources. We find roughly half of all the Planck compact sources are resolved by Herschel into multiple discrete objects, with the other half remaining unresolved by Herschel. We find a significant difference between versions of the Planck catalogues, with earlier releases hosting a larger fraction of candidate proto-clusters and Galactic Cirrus than later releases, which we ascribe to a difference in the filters used in the creation of the three catalogues. We find a surface density of DSFG candidate proto-clusters of (3.3 $\pm$ 0.7) x 10^(-2) sources deg^(-2), in good agreement with previous similar studies. We find that a Planck colour selection of S_{857}/S_{545} < 2 works well to select candidate proto-clusters, but can miss proto-clusters at z < 2. The Herschel colours of individual candidate proto-cluster members indicate our candidate proto-clusters all likely all lie at z > 1. Our candidate proto-clusters are a factor of 5 times brighter at 353 GHz than expected from simulations, even in the most conservative estimates. Further observations are needed to confirm whether these candidate proto-clusters are physical clusters, multiple proto-clusters along the line of sight, or chance alignments of unassociated sources., Resubmitted to MNRAS after request for minor revision

Here we describe the various elements of the Herschel cryogenic concept and its evolution since the first proposal submitted to ESA in 1982, following developments from previous cryogenic missions, and continuous adaptation to the evolving needs of the focal plane instruments, ending in a substantially different concept. A temperature below 2 K was necessary for the Herschel instruments to achieve the required sensitivity. Herschel therefore carried a liquid He cryostat of 2300 l capacity, with the liquid in the superfluid phase at a temperature of 1.6 K. This temperature was optimum for the photoconductive detectors of the PACS spectrometer and for the SIS mixers of the heterodyne HIFI instrument. The detectors of the PACS camera and of the SPIRE camera and spectrometer were bolometers, which required an even lower operating temperature. To achieve this, PACS and SPIRE had their own 3He sorption coolers to reach a temperature of 0.3 K. The telescope was launched warm and, once in orbit, cooled passively down to a temperature of ~85 K.

Aims: To constrain models of high-mass star formation, the Herschel-HOBYS key program aims at discovering massive dense cores (MDCs) able to host the high-mass analogs of low-mass prestellar cores, which have been searched for over the past decade. We here focus on NGC 6334, one of the best-studied HOBYS molecular cloud complexes. Methods: We used Herschel/PACS and SPIRE 70-500 μm images of the NGC 6334 complex complemented with (sub)millimeter and mid-infrared data. We built a complete procedure to extract 0.1 pc dense cores with the getsources software, which simultaneously measures their far-infrared to millimeter fluxes. We carefully estimated the temperatures and masses of these dense cores from their spectral energy distributions (SEDs). We also identified the densest pc-scale cloud structures of NGC 6334, one 2 pc × 1 pc ridge and two 0.8 pc × 0.8 pc hubs, with volume-averaged densities of 105 cm-3. Results: A cross-correlation with high-mass star formation signposts suggests a mass threshold of 75 M☉ for MDCs in NGC 6334. MDCs have temperatures of 9.5-40 K, masses of 75-1000 M☉, and densities of 1 × 105-7 × 107 cm-3. Their mid-infrared emission is used to separate 6 IR-bright and 10 IR-quiet protostellar MDCs while their 70 μm emission strength, with respect to fitted SEDs, helps identify 16 starless MDC candidates. The ability of the latter to host high-mass prestellar cores is investigated here and remains questionable. An increase in mass and density from the starless to the IR-quiet and IR-bright phases suggests that the protostars and MDCs simultaneously grow in mass. The statistical lifetimes of the high-mass prestellar and protostellar core phases, estimated to be 1-7 × 104 yr and at most 3 × 105 yr respectively, suggest a dynamical scenario of high-mass star formation. Conclusions: The present study provides good mass estimates for a statistically significant sample, covering the earliest phases of high-mass star formation. High-mass prestellar cores may not exist in NGC 6334, favoring a scenario presented here, which simultaneously forms clouds, ridges, MDCs, and high-mass protostars. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. Catalogs built from Tables A.1-A.12, are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/602/A77

Bolometers are used as detectors in the Herschel SPIRE and PACS instruments. This chapter focuses on the history of bolometer development leading to the SPIRE and PACS detectors, operating in the submillimetre and far-infrared wavelength ranges. This historical and technological review describes the main technical lineages of bolometers and how the SPIRE and PACS instruments on Herschel, respectively, employed both an adapted and improved variant of a well-established technology and a novel bolometer architecture developed especially for the mission.

The principles and practice of astronomical imaging Fourier transform spectroscopy (FTS) at far-infrared wavelengths are described. The Mach-Zehnder interferometer design has been widely adopted for current and future imaging FTS instruments; we compare this design with two other common interferometer formats. Examples of three instruments based on the Mach-Zehnder design are presented. The techniques for retrieving astrophysical parameters from the measured spectra are discussed using calibration data obtained with the Herschel SPIRE instrument. The paper concludes with an example of imaging spectroscopy obtained with the SPIRE FTS instrument., 10 pages; 9 figures. Accepted for publication in the Canadian Journal of Physics. v2: minor typographical changes to match published version

We describe the procedure used to flux calibrate the three-band submillimetre photometer in the Spectral and Photometric Imaging REceiver (SPIRE) instrument on the Herschel Space Observatory. This includes the equations describing the calibration scheme, a justification for using Neptune as the primary calibration source, a description of the observations and data processing procedures used to derive flux calibration parameters (for converting from voltage to flux density) for every bolometer in each array, an analysis of the error budget in the flux calibration for the individual bolometers, and tests of the flux calibration on observations of primary and secondary calibrators. The procedure for deriving the flux calibration parameters is divided into two parts. In the first part, we use observations of astronomical sources in conjunction with the operation of the photometer internal calibration source to derive the unscaled derivatives of the flux calibration curves. To scale the calibration curves in Jy/beam/V, we then use observations of Neptune in which the beam of each bolometer is mapped using Neptune observed in a very fine scan pattern. The total instrumental uncertainties in the flux calibration for the individual bolometers is ~0.5% for most bolometers, although a few bolometers have uncertainties of ~1-5% because of issues with the Neptune observations. Based on application of the flux calibration parameters to Neptune observations performed using typical scan map observing modes, we determined that measurements from each array as a whole have instrumental uncertainties of 1.5%. This is considerably less than the absolute calibration uncertainty associated with the model of Neptune, which is estimated at 4%., 20 pages, 17 figures, accepted for publication in MNRAS

Astrophysical images issued from different instruments and/or spectral bands often require to be processed together, either for fitting or comparison purposes. However each image is affected by an instrumental response, also known as PSF, that depends on the characteristics of the instrument as well as the wavelength and the observing strategy. Given the knowledge of the PSF in each band, a straightforward way of processing images is to homogenise them all to a target PSF using convolution kernels, so that they appear as if they had been acquired by the same instrument. We propose an algorithm that generates such PSF-matching kernels, based on Wiener filtering with a tunable regularisation parameter. This method ensures all anisotropic features in the PSFs to be taken into account. We compare our method to existing procedures using measured Herschel/PACS and SPIRE PSFs and simulated JWST/MIRI PSFs. Significant gains up to two orders of magnitude are obtained with respect to the use of kernels computed assuming Gaussian or circularised PSFs., 7 pages, 6 figure. Accepted for publication in A&A ; code available at https://github.com/aboucaud/pypher

We have carried out two extremely deep surveys with SPIRE, one of the two cameras on Herschel, at 250 microns, close to the peak of the far-infrared background. We have used the results to investigate the evolution of the rest-frame 250-micron luminosity function out to z=2. We find evidence for strong evolution out to a redshift of around 1 but evidence for at most weak evolution beyond this redshift. Our results suggest that a significant part of the stars and metals in the Universe today were formed at z, Astronomy and Astrophysics, Herschel Special Issue, in press as a Letter; 5 pages

This paper explores the concept of utilizing a long duration stratospheric airship as an astronomical observatory in the sub-millimetre wavelengths. In the first section of the paper, a conceptual description of the airship platform is presented along with the principles of operation of the platform. The results of a computer design code and trajectory simulation code are presented. These codes show that through the use of a modest power and propulsion system, the difficulty of constructing such a such a platform is greatly reduced. Finally, the results of a brief study into the accommodation and optical performance of a Ø3.5m class telescope and photometric and spectrographic instrument similar to the Herschel/SPIRE system within such an airship are presented. This study indicates that while the atmospheric absorption and emission characteristics impose some limitations on the spectrographic and photometric performance of the system in the 200μm to 1000μm band, the overall performance is more than adequate to render the concept viable and complementary to existing and planned ground, airborne and space based observatories.

著者人数: 91名, Accepted: 2011-04-08, 資料番号: SA1003030000

We report Herschel SPIRE (250, 350, and 500 micron) detections of 32 quasars with redshifts 0.5 < z < 3.6 from the Herschel Multi-tiered Extragalactic Survey. These sources are from a MIPS 24 micron flux-limited sample of 326 quasars in the Lockman Hole Field. The extensive multi-wavelength data available in the field permit construction of the rest-frame Spectral Energy Distributions (SEDs)from ultraviolet to the mid-infrared for all sources, and to the far-infrared (FIR) for the 32 objects. Most quasars with Herschel FIR detections show dust temperatures in the range of 25K to 60K, with a mean of 34K. The FIR luminosities range from 10^{11.3} to 10^{13.5} Lsun, qualifying most of their hosts as ultra- or hyper-luminous infrared galaxies. These FIR-detected quasars may represent a dust-rich population, but with lower redshifts and fainter luminosities than quasars observed at ~ 1 mm. However, their FIR properties cannot be predicted from shorter wavelengths (0.3--20 micron, rest-frame), and the bolometric luminosities derived using the 5100 A index may be underestimated for these FIR-detected quasars. Regardless of redshift, we observed a decline in the relative strength of FIR luminosities for quasars with higher near-infrared luminosities., 11 pages, 6 figures, 1 table. Accepted for publication in ApJ

As part of the Herschel Multi-tiered Extragalactic Survey we have investigated the rest-frame far-infrared (FIR) properties of a sample of more than 4800 Lyman Break Galaxies (LBGs) in the Great Observatories Origins Deep Survey North field. Most LBGs are not detected individually, but we do detect a sub-sample of 12 objects at 0.7 < z < 1.6 and one object at z ~ 2.0. The ones detected by Herschel SPIRE have redder observed NUV-U and U-R colors than the others, while the undetected ones have colors consistent with average LBGs at z > 2.5. The UV-to-FIR spectral energy distributions of the objects detected in the rest-frame FIR are investigated using the code CIGALE to estimate physical parameters. We find that LBGs detected by SPIRE are high mass, luminous infrared galaxies. It appears that LBGs are located in a triangle-shaped region in the A_FUV vs. Log L_FUV diagram limited by A_FUV=0 at the bottom and by a diagonal following the temporal evolution of the most massive galaxies from the bottom-right to the top-left of the diagram. This upper envelop can be used as upper limits for the UV dust attenuation as a function of L_FUV}. The limits of this region are well explained using a closed-box model, where the chemical evolution of galaxies produces metals, which in turn lead to higher dust attenuation when the galaxies age., Comment: ApJ Letter in press

Selecting sources with rising flux densities towards longer wavelengths from Herschel/SPIRE maps is an efficient way to produce a catalogue rich in high-redshift (z > 4) dusty star-forming galaxies. The effectiveness of this approach has already been confirmed by spectroscopic follow-up observations, but the previously available catalogues made this way are limited by small survey areas. Here we apply a map-based search method to 274 deg$^2$ of the HerMES Large Mode Survey (HeLMS) and create a catalogue of 477 objects with SPIRE flux densities $S_{500} > S_{350} >S_{250}$ and a $5 ��$ cut-off $S_{500} > $ 52 mJy. From this catalogue we determine that the total number of these "red" sources is at least an order of magnitude higher than predicted by galaxy evolution models. These results are in agreement with previous findings in smaller HerMES fields; however, due to our significantly larger sample size we are also able to investigate the shape of the red source counts for the first time. We have obtained spectroscopic redshift measurements for two of our sources using the Atacama Large Millimeter/submillimeter Array (ALMA). The redshifts z = 5.1 and z = 3.8 confirm that with our selection method we can indeed find high-redshift dusty star-forming galaxies., Accepted by MNRAS

著者人数: 18名, Accepted: 2016-05-19, 資料番号: SA1160054000

Herschel has revolutionized our ability to measure column densities (N$_{\rm H}$) and temperatures (T) of molecular clouds thanks to its far infrared multiwavelength coverage. However, the lack of a well defined background intensity level in the Herschel data limits the accuracy of the N$_{\rm H}$ and T maps. We provide a method that corrects the missing Herschel background intensity levels using the Planck model for foreground Galactic thermal dust emission. We present a Fourier method that combines the publicly available Planck model on large angular scales with the Herschel images on smaller angular scales. We apply our method to two regions spanning a range of Galactic environments: Perseus and the Galactic plane region around $l = 11\deg$ (HiGal--11). We post-process the combined dust continuum emission images to generate column density and temperature maps. We compare these to previously adopted constant--offset corrections. We find significant differences ($\gtrsim$20\%) over significant ($\sim$15\%) areas of the maps, at low column densities ($N_{\rm H}\lesssim10^{22}$\,cm$^{-2}$) and relatively high temperatures ($T\gtrsim20$\,K). We also apply our method to synthetic observations of a simulated molecular cloud to validate our method. Our method successfully corrects the Herschel images, including both the constant--offset intensity level and the scale-dependent background variations measured by Planck. Our method improves the previous constant--offset corrections, which did not account for variations in the background emission levels., Comment: Paper accepted for publications in A&A

We present multiwavelength identifications for the counterparts of 1088 submillimeter sources detected at 850$��$m in the SCUBA-2 Cosmology Legacy Survey study of the UKIDSS-UDS field. By utilising an ALMA pilot study on a subset of our bright SCUBA-2 sample as a training set, along with the deep optical-near-infrared data available in this field, we develop a novel technique, Optical-IR Triple Color (OIRTC), using $z-K$, $K-[3.6]$, $[3.6]-[4.5]$ colors to select the candidate submillimeter galaxy (SMG) counterparts. By combining radio identification and the OIRTC technique, we find counterpart candidates for 80% of the Class = 1 $\geq4\,��$ SCUBA-2 sample, defined as those that are covered by both radio and OIR imaging and the base sample for our scientific analyses. Based on the ALMA training set, we expect the accuracy of these identifications to be $82\pm20$%, with a completeness of $69\pm16$%, essentially as accurate as the traditional $p$-value technique but with higher completeness. We find that the fraction of SCUBA-2 sources having candidate counterparts is lower for fainter 850$��$m sources, and we argue that for follow-up observations sensitive to SMGs with $S_{850}\gtrsim 1$ mJy across the whole ALMA beam, the fraction with multiple counterparts is likely to be $>40$% for SCUBA-2 sources at $S_{850} \gtrsim 4$ mJy. We find that the photometric redshift distribution for the SMGs is well fit by a lognormal distribution, with a median redshift of $z=2.3\pm0.1$. After accounting for the sources without any radio and/or OIRTC counterpart, we estimate the median redshift to be $z=2.6\pm0.1$ for SMGs with $S_{850} >1$ mJy. We also use this new large sample to study the clustering of SMGs and the the far-infrared properties of the unidentified submillimeter sources by stacking their Herschel SPIRE far-infrared emission., ApJ in press, 23 pages, 17 figures

The Herschel/SPIRE FTS used two standard resolution modes: high- and low-res (HR/LR). In a hybrid H+LR mode, a clear systematic discrepancy in the continuum is seen. An empirical correction which removes this noise has been developed.

The SPIRE instrument on the Herschel Space Observatory employed an imaging FTS. The instrumental line shape exhibited a slight asymmetry, constant throughout the mission and virtually independent of wavelength, both suggesting an instrumental origin.

The Herschel/SPIRE team has developed an automated spectral-line fitter as part of its data archive. This tool is validated by comparing source velocities from the line-fitter with known/external velocities for a variety of on-sky targets.

Template-based extrapolations from only one photometric band can be a cost-effective method to estimate the total infrared (IR) luminosities ($L_{\mathrm{IR}}$) of galaxies. By utilizing multi-wavelength data that covers across 0.35--500\,$\mathrm{\mu m}$ in GOODS-North and GOODS-South fields, we investigate the accuracy of this monochromatic extrapolated $L_{\mathrm{IR}}$ based on three IR spectral energy distribution (SED) templates (\citealt[CE01]{Chary2001}; \citealt[DH02]{Dale2002}; \citealt[W08]{Wuyts2008a}) out to $z\sim 3.5$. We find that the CE01 template provides the best estimate of $L_{\mathrm{IR}}$ in {\it Herschel}/PACS bands, while the DH02 template performs best in {\it Herschel}/SPIRE bands. To estimate $L_{\mathrm{IR}}$, we suggest that extrapolations from the available longest wavelength PACS band based on the CE01 template can be a good estimator. Moreover, if PACS measurement is unavailable, extrapolations from SPIRE observations but based on the \cite{Dale2002} template can also provide a statistically unbiased estimate for galaxies at $z\lesssim 2$. The emission of rest-frame 10--100\,$\mathrm{\mu m}$ range of IR SED can be well described by all the three templates, but only the DH02 template shows nearly unbiased estimate of the emission of the rest-frame submillimeter part., Comment: Accepted for publication in the The Astronomical Journal

Every Herschel/SPIRE Imaging FTS observation was accompanied by an equal or greater length observation of the same dark-sky on the same observation day. We present the stacking of these dark sky observations in search of faint spectral features.

We discuss some challenges for the SPIRE-FTS extended source calibration scheme and introduce a correction method using cross-calibration with the SPIRE photometer.

We present the first major data release of the largest single key-project in area carried out in open time with the Herschel Space Observatory. The Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) is a survey of 600 deg^2 in five photometric bands - 100, 160, 250, 350 and 500 um - with the PACS and SPIRE cameras. In this paper and a companion paper (Bourne et al. 2016) we present the survey of three fields on the celestial equator, covering a total area of 161.6 deg^2 and previously observed in the Galaxy and Mass Assembly (GAMA) spectroscopic survey. This paper describes the Herschel images and catalogues of the sources detected on the SPIRE 250 um images. The 1-sigma noise for source detection, including both confusion and instrumental noise, is 7.4, 9.4 and 10.2 mJy at 250, 350 and 500 um. Our catalogue includes 120230 sources in total, with 113995, 46209 and 11011 sources detected at >4-sigma at 250, 350 and 500 um. The catalogue contains detections at >3-sigma at 100 and 160 um for 4650 and 5685 sources, and the typical noise at these wavelengths is 44 and 49 mJy. We include estimates of the completeness of the survey and of the effects of flux bias and also describe a novel method for determining the true source counts. The H-ATLAS source counts are very similar to the source counts from the deeper HerMES survey at 250 and 350 um, with a small difference at 500 um. Appendix A provides a quick start in using the released datasets, including instructions and cautions on how to use them., Accepted by MNRAS; data available at www.h-atlas.org