The tidytext package (Silge, Robinson, and Hester 2016) is an R package (R Core Team 2016) for text mining using tidy data principles. As described by Hadley Wickham (Wickham 2014), tidy data has a specific structure:

The Gemini Near Infrared Spectrograph on Gemini South unlocks new possibilities to study the central black holes (BHs) in dusty galaxies that have been inaccessible to previous BH studies. We exploit good near-infrared seeing to measure the central BH of Centaurus A (NGC 5128). We measure the stellar kinematics of NGC 5128 using the region around the CO band heads at 2.3 m and determine the BH mass using axisymmetric orbit-based models. BHs are believed to be essential components of galaxies, and their evolutionary states appear to be closely linked to those of their hosts. Our current knowledge does not go much beyond this; galaxies such as NGC 5128 (a recent merger with an active galactic nucleus) can further develop this knowledge. However, NGC 5128 and galaxies like it contain large amounts of dust, which hamper optical spectroscopy, making near-infrared measurements an attractive alternative. We find a BH mass of 2:4 þ0:3 À0:2 ; 10 8 M for an edge-on model, 1:8 þ0:4 À0:4 ; 10 8 M for a model with an inclination of 45 , and 1:5 þ0:3 À0:2 ; 10 8 M for a model with an inclination of 20 . We adopt the value for the edge-on model, since it has significantly lower 2 ; however, it is unlikely that we can constrain the actual inclination of moderately triaxial NGC 5128 using an axisymmetric modeling procedure. These estimates, based on adjusting the asymmetric kinematics of NGC 5128 so that we can use an axisymmetric code, are consistent with the range of acceptable BH masses implied by a previous gas dynamical study. However, these estimates are 5-10 times higher than that predicted by the correlation between BH mass and velocity dispersion. If NGC 5128 will eventually follow the trend for quiescent galaxies, this result suggests that its BH assembled first before its host component. NGC 5128 thus provides an important example for our knowledge of central BHs; this technique can be applied to other such galaxies to further explore this question.

We have obtained spectra and measured the stellar kinematics in a sample of 25 nearby early-type galaxies (with velocity dispersions from less than 100 km s À1 to over 300 km s À1 ) using the near-infrared CO absorption band head at 2.29 lm. Our median uncertainty for the dispersions is $10%. We examine the effects of dust on existing optical kinematic measurements. We find that the near-infrared velocity dispersions are, in general, smaller than optical velocity dispersions, with differences as large as 30%. The median difference is 11% smaller, and the effect is of greater magnitude for higher dispersion galaxies. The lenticular galaxies (18 out of 25) appear to be causing the shift to lower dispersions, while the classical elliptical galaxies (7 out of 25) are consistent between the two wavelength regimes. If uniformly distributed dust causes these differences, we would expect to find a correlation between the relative amount of dust in a galaxy and the fractional change in dispersion, but we do not find such a correlation. We do see correlations between both velocity dispersion and CO band head equivalent width, and velocity dispersion and Mg 2 index. The differences in dispersion are not well explained by current models of dust absorption. The lack of correlation between the relative amount of dust and shift in dispersion possibly suggests that dust does not have a similar distribution from galaxy to galaxy. The CO equivalent widths of these galaxies are quite high (e10 Å for almost all), requiring the light at these wavelengths to be dominated by very cool stars.

We have designed, constructed and put into operation a very large area CCD camera that covers the field of view of the 1.2 m Samuel Oschin Schmidt Telescope at the Palomar Observatory. The camera consists of 112 CCDs arranged in a mosaic of four rows with 28 CCDs each. The CCDs are 600 x 2400 pixel Sarnoff thinned, back illuminated devices with 13 um x 13 um pixels. The camera covers an area of 4.6 deg x 3.6 deg on the sky with an active area of 9.6 square degrees. This camera has been installed at the prime focus of the telescope, commissioned, and scientific quality observations on the Palomar-QUEST Variability Sky Survey were started in September of 2003. The design considerations, construction features, and performance parameters of this camera are described in this paper

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