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High-resolution optical spectra of 30 metal-poor stars selected from the \\ survey are presented, based on observations taken with the Gemini Observatory GRACES spectrograph. Stellar parameters and are determined using a Gaia DR2 colour-temperature calibration and surface gravity from the Stefan-Boltzmann equation. GRACES spectra are used to determine chemical abundances (or upper-limits) for 20 elements (Li, O, Na, Mg, K, Ca, Ti, Sc, Cr, Mn, Fe, Ni, Cu, Zn, Y, Zr, Ba, La, Nd, Eu). These stars are confirmed to be metal-poor ([Fe/H]\\(<-2.5\\)), with higher precision than from earlier medium-resolution analyses. The chemistry for most targets is similar to other extremely metal-poor stars in the Galactic halo. Three stars near [Fe/H]\\(=-3.0\\) have unusually low Ca and high Mg, suggestive of contributions from few SN~II where alpha-element formation through hydrostatic nucleosynthesis was more efficient. Three new carbon-enhanced metal-poor stars are also identified (two CEMP-s and one potential CEMP-no star) when our chemical abundances are combined with carbon from previous medium-resolution analyses. The GRACES spectra also provide precision radial velocities (\\(_ RV0.2\\)km\\,s\\(^-1\\)) for dynamical orbit calculations with the Gaia DR2 proper motions. Most of our targets are dynamically associated with the Galactic halo; however, five stars with [Fe/H]\\(<-3\\) have planar-like orbits, including one retrograde star. Another five stars are dynamically consistent with the Gaia-Sequoia accretion event; three have typical halo [\\(\\)/Fe] ratios for their metallicities, whereas two are [Mg/Fe]-deficient, and one is a new CEMP-s candidate. These results are discussed in terms of the formation and early chemical evolution of the Galaxy.

The investigation of the metal-poor tail in the Galactic bulge provides unique information on the early Milky Way assembly and evolution. A chemo-dynamical analysis of 17 very metal-poor stars (VMP, [Fe/H] \\(<-2.0\\)) selected from the Pristine Inner Galaxy Survey was carried out based on Gemini/GRACES spectra. The chemistry suggests that the majority of our stars are very similar to metal-poor stars in the Galactic halo. Orbits calculated from ıt Gaia EDR3 imply these stars are brought into the bulge during the earliest Galactic assembly. Most of our stars have large [Na,Ca/Mg] abundances, and thus show little evidence of enrichment by pair-instability supernovae. Two of our stars (P171457, P184700) have chemical abundances compatible with second-generation globular cluster stars, suggestive of the presence of ancient and now dissolved globular clusters in the inner Galaxy. One of them (P171457) is extremely metal-poor ([Fe/H] \\(<-3.0\\)) and well below the metallicity floor of globular clusters, which supports the growing evidence for the existence of lower-metallicity globular clusters in the early Universe. A third star (P180956, [Fe/H] \\(-2\\)) has low [Na,Ca/Mg] and very low [Ba/Fe] for its metallicity, which are consistent with formation in a system polluted by only one or a few low-mass supernovae. Interestingly, its orbit is confined to the Galactic plane, like other very metal-poor stars found in the literature, which have been associated with the earliest building blocks of the Milky Way.

The SDSS-III APOGEE DR12 is a unique resource to search for stars beyond the tidal radii of star clusters. We have examined the APOGEE DR12 database for new candidates of the young star cluster Palomar 1, a system with previously reported tidal tails (Niederste-Ostholt et al. 2010). The APOGEE ASPCAP database includes spectra and stellar parameters for two known members of Pal 1 (Stars I and II), however these do not agree with the stellar parameters determined from optical spectra by Sakari et al. (2011). We find that the APOGEE analysis of these two stars is strongly affected by the known persistence problem (Majewski et al. 2015; Nidever et al. 2015). By re-examining the individual visits, and removing the blue (and sometimes green) APOGEE detector spectra affected by persistence, then we find excellent agreement in a re-analysis of the combined spectra. These methods are applied to another five stars in the APOGEE field with similar radial velocities and metallicities as those of Pal 1. Only one of these new candidates, Star F, may be a member located in the tidal tail based on its heliocentric radial velocity, metallicity, and chemistry. The other four candidates are not well aligned with the tidal tails, and comparison to the Besancon model (Robin et al. 2003) suggests that they are more likely to be non-members, i.e. part of the Galactic halo. This APOGEE field could be re-examined for other new candidates if the persistence problem can be removed from the APOGEE spectral database.

We present the results of an automated fibre optic test bench constructed at the University of Victoria as part of the Maunakea Spectroscopic Explorer (MSE) Fibre Transmission System (FiTS). In preparation for MSE-FiTS, we have begun characterizing the focal ratio degradation (FRD) of candidate multi-mode fibres with the ultimate goal of testing all ~4000 MSE fibres. To achieve this, we have built an optical bench to perform an automated version of the collimated beam test. Herein we present the design of the bench and discuss the automation of components by introducing the Big FiTS Fibre Wrapper (Big FFW), our open-source automation software. We conclude with the results of tests performed using the Big FFW on a sample of candidate fibre, comparing the Big FFW results against those found using manual methods. Our results suggest that the candidate MSE fibre meets the science requirement of < 5% FRD at f=2 and less than 1% disagreement between both measurement methods.

We identify six new CEMP stars ([C/Fe]>+0.7 and [Fe/H]< -1.8) and another seven likely candidates within the APOGEE database following Data Release 12. These stars have chemical compositions typical of metal-poor halo stars, e.g., mean [\\(\\)/Fe] = +0.24\\(\\)0.24, based on the ASPCAP pipeline results. A lack of heavy element spectral lines impedes further sub-classification of these CEMP stars, however, based on radial velocity scatter, we predict most are not CEMP-s stars which are typically found in binary systems. Only one object, 2M15312547+4220551, may be in a binary since it exhibits a scatter in its radial velocity of 1.7 \\(\\)0.6 km s\\(^-1\\) based on three visits over a 25.98 day baseline. Optical observations are now necessary to confirm the stellar parameters and low metallicities of these stars, to determine the heavy-element abundance ratios and improve the precision in the derived abundances, and to examine their CEMP sub-classifications.

We present optical template spectra, bolometric corrections, and chi values for ultracool dwarfs. The templates are based on spectra from the Sloan Digital Sky Survey (SDSS) and the Astrophysical Research Consortium 3.5 m telescope. The spectral features and overall shape of the L dwarf templates are consistent with previous spectroscopic standards and the templates have a radial velocity precision of ~10-20 km s super(-1). We calculate bolometric fluxes (accurate to 10-20%) for 101 late-M and L dwarfs from SDSS, 2MASS, and WISE photometry, SDSS spectra, and BT-Settl model spectra. We find that the 3-band and J-band bolometric corrections for late-M and L dwarfs have a strong correlation with z-J and J-KS colors, respectively. The new chi values, which can be used to convert Ha equivalent widths to activity strength, are based on spectrophotometrically calibrated SDSS spectra and the new bolometric fluxes. While the measured chi values have typical uncertainties of ~20%, ultracool dwarf models show the continuum surrounding Ha can vary by up to an order of magnitude with changing surface gravity. Our semiempirical chi values are one to two orders of magnitude larger than previous chi values for mid-to-late L dwarfs, indicating that the upper limits for Ha activity strength on the coolest L dwarfs have been underestimated.

We present optical template spectra, bolometric corrections, and χ values for ultracool dwarfs. The templates are based on spectra from the Sloan Digital Sky Survey (SDSS) and the Astrophysical Research Consortium 3.5 m telescope. The spectral features and overall shape of the L dwarf templates are consistent with previous spectroscopic standards and the templates have a radial velocity precision of ∼10–20 km s-1. We calculate bolometric fluxes (accurate to 10–20%) for 101 late-M and L dwarfs from SDSS, 2MASS, and WISE photometry, SDSS spectra, and BT-Settl model spectra. We find that thez-band andJ-band bolometric corrections for late-M and L dwarfs have a strong correlation withz–JandJ–K S colors, respectively. The new χ values, which can be used to convert Hα equivalent widths to activity strength, are based on spectrophotometrically calibrated SDSS spectra and the new bolometric fluxes. While the measured χ values have typical uncertainties of ∼20%, ultracool dwarf models show the continuum surrounding Hα can vary by up to an order of magnitude with changing surface gravity. Our semiempirical χ values are one to two orders of magnitude larger than previous χ values for mid-to-late L dwarfs, indicating that the upper limits for Hα activity strength on the coolest L dwarfs have been underestimated.

We present optical template spectra, bolometric corrections, and χ values for ultracool dwarfs. The templates are based on spectra from the Sloan Digital Sky Survey (SDSS) and the Astrophysical Research Consortium 3.5 m telescope. The spectral features and overall shape of the L dwarf templates are consistent with previous spectroscopic standards and the templates have a radial velocity precision of ∼10-20 km s-1. We calculate bolometric fluxes (accurate to 10-20%) for 101 late-M and L dwarfs from SDSS, 2MASS, and WISE photometry, SDSS spectra, and BT-Settl model spectra. We find that the z-band and J-band bolometric corrections for late-M and L dwarfs have a strong correlation with z-J and J-KS colors, respectively. The new χ values, which can be used to convert Hα equivalent widths to activity strength, are based on spectrophotometrically calibrated SDSS spectra and the new bolometric fluxes. While the measured χ values have typical uncertainties of ∼20%, ultracool dwarf models show the continuum surrounding Hα can vary by up to an order of magnitude with changing surface gravity. Our semiempirical χ values are one to two orders of magnitude larger than previous χ values for mid-to-late L dwarfs, indicating that the upper limits for Hα activity strength on the coolest L dwarfs have been underestimated.

We present optical template spectra, bolometric corrections, and \\(\\) values for ultracool dwarfs. The templates are based on spectra from the Sloan Digital Sky Survey (SDSS) and the Astrophysical Research Consortium 3.5-m telescope. The spectral features and overall shape of the L dwarf templates are consistent with previous spectroscopic standards and the templates have a radial velocity precision of \\(\\)10--20 km s\\(^-1\\). We calculate bolometric fluxes (accurate to 10--20\\%) for 101 late-M and L dwarfs from SDSS, 2MASS, and WISE photometry, SDSS spectra, and BT-Settl model spectra. We find that the \\(z\\)- and \\(J\\)-band bolometric corrections for late-M and L dwarfs have a strong correlation with \\(z-J\\) and \\(J-K_S\\) colors respectively. The new \\(\\) values, which can be used to convert H\\(\\) equivalent widths to activity strength, are based on spectrophotometrically calibrated SDSS spectra and the new bolometric fluxes. While the measured \\(\\) values have typical uncertainties of \\(\\)20\\%, ultracool dwarf models show the continuum surrounding H\\(\\) can vary by up to an order of magnitude with changing surface gravity. Our semi-empirical \\(\\) values are one to two orders of magnitude larger than previous \\(\\) values for mid- to late-L dwarfs, indicating that the upper limits for H\\(\\) activity strength on the coolest L dwarfs have been underestimated.