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We analyze the dust properties of 57 870 $\mu$m selected dusty star-forming galaxies in the GOODS-S using new deep ALMA 1.2 mm, 2 mm, and 3 mm continuum imaging together with other far-infrared through millimeter data. We fit the spectral energy distributions (SEDs) with optically thin modified blackbodies to constrain the emissivity indices and effective dust temperatures, finding a median emissivity index of $\beta = 1.78^{+0.43}_{-0.25}$ and a median temperature of $T_d = 33.6^{+12.1}_{-5.4}$ K. We observe a negative correlation between $\beta$ and $T_d$. By testing several SED models, we determine that the derived emissivity indices can be influenced by opacity assumptions. Our temperature measurements are consistent with no evolution in dust temperature with redshift., Comment: Accepted for publication in ApJ. 21 pages, 12 figures, 2 tables

We present deep SCUBA-2 450 micron and 850 micron imaging of ten strong lensing clusters. We provide a >4-sigma SCUBA-2 850 micron catalog of the 404 sources lying within a radius of 4.5' from the cluster centers. We also provide catalogs of the >4.5-sigma ALMA 870 micron detections in the clusters A370, MACSJ1149.5+2223, and MACSJ0717.5+3745 from our targeted ALMA observations, along with catalogs of all other >4.5-sigma ALMA (mostly 1.2 mm) detections in any of our cluster fields from archival ALMA observations. For the ALMA detections, we give spectroscopic or photometric redshifts, where available, from our own Keck observations or from the literature. We confirm the use of the 450 micron to 850 micron flux ratio for estimating redshifts. We use lens models to determine magnifications, most of which are in the 1.5-4 range. After supplementing the ALMA cluster sample with Chandra Deep Field (CDF) ALMA and SMA samples, we find no evidence for evolution in the redshift distribution of submillimeter galaxies down to demagnified 850 micron fluxes of 0.5 mJy. Given this result, we conclude that our observed trend of increasing F160W to 850 micron flux ratio from brighter to fainter demagnified 850 micron flux results from the fainter submillimeter galaxies having less extinction. However, there is wide spread in this relation, including the presence of some optical/NIR dark galaxies down to fluxes below 1 mJy. Finally, with insights from our ALMA analysis, we analyze our SCUBA-2 sample and present 55 850 micron-bright z>4 candidates., Comment: 33 pages, resubmitted to ApJ after responding to referee report

We present the source associations, cross-identifications, and multi-wavelength properties of the faint radio source population detected in the deep tier of the LOFAR Two Metre Sky Survey (LoTSS): the LoTSS Deep Fields. The first LoTSS Deep Fields data release consists of deep radio imaging at 150~MHz of the ELAIS-N1, Lockman Hole, and Bo\"{o}tes fields, down to RMS sensitives of around 20, 22, and 32$~\mu$Jy\,beam$^{-1}$, respectively. These fields are some of the best studied extra-galactic fields in the northern sky, with existing deep, wide-area panchromatic photometry from X-ray to infrared wavelengths, covering a total of $\approx$~26~\mbox{deg$^{2}$}. We first generated improved multi-wavelength catalogues in ELAIS-N1 and Lockman Hole; combined with the existing catalogue for Bo\"{o}tes, we present forced, matched aperture photometry for over 7.2 million sources across the three fields. We identified multi-wavelength counterparts to the radio detected sources, using a combination of the Likelihood Ratio method and visual classification, which greatly enhances the scientific potential of radio surveys and allows for the characterisation of the photometric redshifts and the physical properties of the host galaxies. The final radio-optical cross-matched catalogue consists of 81\,951 radio-detected sources, with counterparts identified and multi-wavelength properties presented for 79\,820 ($>$97\%) sources. We also examine the properties of the host galaxies, and through stacking analysis find that the radio population with no identified counterpart is likely dominated by AGN at $z\sim3-4$. This dataset contains one of the largest samples of radio-selected star-forming galaxies and active galactic nuclei (AGN) at these depths, making it ideal for studying the history of star-formation, and the evolution of galaxies and AGN across cosmic time., Comment: 34 pages, 14 figures and 14 tables. Accepted for publication in A&A special issue. This paper is part of the 1st data release of the LoTSS Deep Fields. Electronic data catalogues will be made available on journal publication

We present the results of the first dedicated survey for 22 GHz H$_2$O maser emission in dwarf galaxies outside of the local group, with the aim of discovering disc masers. Studies of disc masers yield accurate and precise measurements of black hole mass, and such measurements in dwarf galaxies would be key to understanding the low-mass end of BH-galaxy co-evolution. We used the Green Bank Telescope to survey 100 nearby ($z \lesssim 0.055$) dwarf galaxies ($M_* \lesssim 10^{9.5}~M_{\odot}$) with optical emission line ratios indicative of accretion onto a massive black hole. We detected no new masers down to a limit of $\sim$12 mJy (5$\sigma$). We compared the properties of our sample with those of $\sim$1,850 known detections and non-detections in massive galaxies. We find, in agreement with previous studies, that masers are preferentially hosted by Seyferts and highly-obscured, [O III]-bright AGNs. Our sample has fewer Seyferts, is less obscured, and is [O III]-faint. Though the overall maser detection rate is $\sim$3% in massive galaxies, the predicted rate for our sample, weighted by its optical properties, is $\sim$0.6-1.7%, corresponding to a probability of making no detections of $\sim$20-50%. We also found a slight increase in the detection rate with increased stellar mass in previously surveyed galaxies. However, further observations are required to discern whether there is an intrinsic difference between the maser fraction in active dwarf galaxies and in their massive counterparts for the same AGN properties., Comment: 18 pages, 9 figures. Accepted to MNRAS