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We report spectroscopic redshift measurements for three bright submillimeter galaxies (SMGs) near the GOODS-N field, each with SCUBA-2 850 micron fluxes > 10 mJy, using the Northern Extended Millimeter Array (NOEMA). Our molecular linescan observations of these sources, which occupy a ~7 arcmin$^2$ area outside of the HST coverage of the field, reveal that two lie at $z \sim$ 3.14. In the remaining object, we detect line emission consistent with CO(7-6), [C I], and H2O at $z$ = 4.42. The far-infrared spectral energy distributions of these galaxies, constrained by SCUBA-2, NOEMA, and Herschel/SPIRE, indicate instantaneous SFRs $\sim4000 ~{\rm M_{\odot}~yr^{-1}}$ in the $z$ = 4.42 galaxy and $\sim 2500~{\rm M_{\odot}~yr^{-1}}$ in the two $z \sim$ 3.14 galaxies. Based on our sources' CO line luminosities, we estimate $M_{{\rm gas}}\sim10^{11} M_{\odot}$ and find gas depletion timescales of $\tau_{{\rm depl}}\sim 50$ Myr, consistent with findings in other high-redshift SMGs. Finally, we show that the two $z \sim$ 3.14 sources, which alone occupy a volume $\sim$10 Mpc$^3$, very likely mark the location of a protocluster of bright SMGs and less dusty optical sources., Comment: Newest version: 12 pages, 6 figures, 2 tables; added references and revised arguments in Section 4, results unchanged. Accepted to ApJ. First version: 8 pages, 3 figures, 2 tables. Submitted to ApJ Letters

We present a multi-wavelength study of the active galactic nucleus in the nearby ($D=14.1$ Mpc) low mass galaxy IC 750, which has circumnuclear 22 GHz water maser emission. The masers trace a nearly edge-on, warped disk $\sim$0.2 pc in diameter, coincident with the compact nuclear X-ray source which lies at the base of the $\sim$kpc-scale extended X-ray emission. The position-velocity structure of the maser emission indicates the central black hole (BH) has a mass less than $1.4 \times 10^5~M_\odot$. Keplerian rotation curves fitted to these data yield enclosed masses between $4.1 \times 10^4~M_\odot$ and $1.4 \times 10^5~M_\odot$, with a mode of $7.2 \times 10^4~M_\odot$. Fitting the optical spectrum, we measure a nuclear stellar velocity dispersion $\sigma_* = 110.7^{+12.1}_{-13.4}$~{\rm km~s}$^{-1}.$ From near-infrared photometry, we fit a bulge mass of $(7.3 \pm 2.7) \times 10^8~M_\odot$ and a stellar mass of $1.4 \times 10^{10}~M_\odot$. The mass upper limit of the intermediate mass black hole in IC 750 falls roughly two orders of magnitude below the $M_{\rm BH}-\sigma_*$ relation and roughly one order of magnitude below the $M_{\rm BH}-M_{\rm Bulge}$ and $M_{\rm BH}-M_*$ relations -- larger than the relations' intrinsic scatters of (0.58 $\pm$ 0.09) dex, 0.69 dex, and (0.65 $\pm$ 0.09) dex, respectively. These offsets could be due to larger scatter at the low mass end of these relations. Alternatively, black hole growth is intrinsically inefficient in galaxies with low bulge and/or stellar masses, which causes the black holes to be under-massive relative to their hosts, as predicted by some galaxy evolution simulations., Comment: Accepted for publication in ApJ