Article describes how the most reliable single-epoch supermassive black hole mass (MBH) estimates in quasars are obtained by using the velocity widths of low-ionization emission lines, typically the Hβλ4861 line. The authors find that utilizing both emission lines, where available, reduces the scatter of UV-based MBH estimates by ∼15% when compared to previous studies.

Article presents how to enhance ice contrast in the visible spectrum by using ice birefringence and polarized light reflection. The method can be used for both visual inspection and automatic ice detection systems.

Article describes how quasars at z ≳ 1 most often have redshifts measured from rest-frame ultraviolet emission lines. One of the most common such lines, C ivλ1549, shows blueshifts up to ≈5000 km s−1 and in rare cases even higher. The authors present spectroscopic measurements for 260 sources at 1.55 ≲ z ≲ 3.50 having −28.0 ≲ Mi ≲ − 30.0 mag from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS) catalog, augmenting the previous iteration, which contained 226 of the 260 sources whose measurements are improved upon in this work.