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Open clusters are unique tracers of the history of our own Galaxy's disc. According to our membership analysis based on Gaia astrometry, out of the 226 potential clusters falling in the footprint of the GALactic Archaeology with HERMES (GALAH) survey or the Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey, we find that 205 have secure members that were observed by at least one of the surveys. Furthermore, members of 134 clusters have high-quality spectroscopic data that we use to determine their chemical composition. We leverage this information to study the chemical distribution throughout the Galactic disc of 21 elements, from C to Eu. The radial metallicity gradient obtained from our analysis is −0.076 ± 0.009 dex kpc−1, which is in agreement with previous works based on smaller samples. Furthermore, the gradient in the [Fe/H]–guiding radius (r guid) plane is −0.073 ± 0.008 dex kpc−1. We show consistently that open clusters trace the distribution of chemical elements throughout the Galactic disc differently than field stars. In particular, at the given radius, open clusters show an age–metallicity relation that has less scatter than field stars. As such scatter is often interpreted as an effect of radial migration, we suggest that these differences are due to the physical selection effect imposed by our Galaxy: clusters that would have migrated significantly also had higher chances to get destroyed. Finally, our results reveal trends in the [X/Fe]– r guid–age space, which are important to understand production rates of different elements as a function of space and time. [ABSTRACT FROM AUTHOR]

Several recent spectroscopic investigations have presented conflicting results on the existence of Na-rich asymptotic giant branch (AGB) stars in the Galactic globular cluster M 4 (NGC 6121). The studies disagree on whether or not Na-rich red giant branch (RGB) stars evolve to the AGB. For a sample of previously published HERMES/AAT AGB and RGB stellar spectra, we present a re-analysis of O, Na, and Fe abundances, and a new analysis of Mg and Al abundances; we also present CN band strengths for this sample, derived from low-resolution AAOmega spectra. Following a detailed literature comparison, we find that the AGB samples of all studies consistently show lower abundances of Na and Al, and are weaker in CN, than RGB stars in the cluster. This is similar to recent observations of AGB stars in NGC 6752 and M 62. In an attempt to explain this result, we present new theoretical stellar evolutionary models for M 4; however, these predict that all stars, including Na-rich RGB stars, evolve on to the AGB. We test the robustness of our abundance results using a variety of atmospheric models and spectroscopic methods; however, we do not find evidence that systematic modelling uncertainties can explain the apparent lack of Na-rich AGB stars in M 4. We conclude that an unexplained, but robust, discordance between observations and theory remains for the AGB stars in M 4. [ABSTRACT FROM AUTHOR]

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The prototype star for the γ Doradus class of pulsating variables was studied employing photometric and spectroscopic observations to determine the frequencies and modes of pulsation. The four frequencies found are self-consistent between the observation types and almost identical to those found in previous studies (1.3641 d-1, 1.8783 d-1, 1.4742 d-1, and 1.3209 d-1). Three of the frequencies are classified as l, m = (1, 1) pulsations and the other is ambiguous between l, m = (2, 0) and (2, -2) modes. Two frequencies are shown to be stable over 20 yr since their first identification. The agreement in ground-based work makes this star an excellent calibrator between high-precision photometry and spectroscopy with the upcoming TESS observations and a potential standard for continued asteroseismic modelling. [ABSTRACT FROM AUTHOR]

The prototype star for the γ Doradus class of pulsating variables was studied employing photometric and spectroscopic observations to determine the frequencies and modes of pulsation. The four frequencies found are self-consistent between the observation types and almost identical to those found in previous studies (1.3641 d-1, 1.8783 d-1, 1.4742 d-1 and 1.3209 d-1). Three of the frequencies are classified as l, m = (1, 1) pulsations and the other is ambiguous between l, m = (2, 0) and (2, -2) modes. Two frequencies are shown to be stable over 20 yr since their first identification. The agreement in ground-based work makes this star an excellent calibrator between high-precision photometry and spectroscopy with the upcoming TESS observations and a potential standard for continued asteroseismic modelling. [ABSTRACT FROM AUTHOR]

It has been well established that Galactic Globular clusters (GCs) harbour more than one stellar population, distinguishable by the anticorrelations of light-element abundances (C-N, Na-O, and Mg-Al). These studies have been extended recently to the asymptotic giant branch (AGB). Here, we investigate the AGB of NGC6397 for the first time. We have performed an abundance analysis of high-resolution spectra of 47 red giant branch (RGB) and eight AGB stars, deriving Fe, Na, O, Mg, and Al abundances. We find that NGC6397 shows no evidence of a deficit in Na-rich AGB stars, as reported for some other GCs - the subpopulation ratios of the AGB and RGB in NGC6397 are identical, within uncertainties. This agrees with expectations from stellar theory. This GC acts as a control for our earlier work on the AGB of M4 (with contrasting results), since the same tools and methods were used. [ABSTRACT FROM AUTHOR]

The gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. The MUSICIAN programme at the University of Canterbury has been successfully identifying frequencies and pulsation modes in many γ Doradus stars using hundreds of precise, high resolution spectroscopic observations obtained with the 1.0 m telescope and HERCULES spectrograph at the Mt John Observatory in New Zealand. In this paper we present a summary of our spectroscopic frequency and mode identifications. Of particular interest from our spectroscopic analyses are: the prevalence of (ℓ, m) = 1, 1 modes in many γ Dor stars; the importance of stellar rotation in the interpretation of the frequency and mode identification; and finally, possible evidence of wave leakage in one of these stars. [ABSTRACT FROM PUBLISHER]

The musician programme at the University of Canterbury has been successfully identifying pulsation modes in many γ Doradus stars using hundreds of ground-based spectroscopic observations. This paper describes some of the successful mode identifications and emerging patterns of the programme. The hybrid γ Doradus/δ Scuti star HD 49434 remains an enigma, despite the analysis of more than 1700 multi-site high-resolution spectra. A new result for this star is apparently distinct line-profile variations for the γ Doradus and δ Scuti frequencies. [ABSTRACT FROM PUBLISHER]

ABSTRACT Using multisite spectroscopic data collected from three sites, the frequencies and pulsational modes of the γ Doradus star HD 12901 were identified. A total of six frequencies in the range 1-2 d−1 were observed, their identifications supported by multiple line-profile measurement techniques and previously published photometry. Five frequencies were of sufficient signal-to-noise ratio for mode identification, and all five displayed similar three-bump standard deviation profiles which were fitted well with ( l, m) = (1,1) modes. These fits had reduced χ2 values of less than 18. We propose that this star is an excellent candidate to test models of non-radially pulsating γ Doradus stars as a result of the presence of multiple (1,1) modes. [ABSTRACT FROM AUTHOR]

ABSTRACT We have determined stellar parameters and abundances for 221 giant branch stars in the globular cluster ω Centauri. A combination of photometry and lower resolution spectroscopy was used to determine temperature, gravity, metallicity, [C/Fe], [N/Fe] and [Ba/Fe]. These abundances agree well with those found by previous researchers and expand the analysed sample of the cluster. k-means clustering analysis was used to group the stars into four homogeneous groups based upon these abundances. These stars show the expected anticorrelation between [C/Fe] and [N/Fe]. We investigated the distribution of CN-weak/CN-strong stars on the colour-magnitude diagram. Asymptotic giant branch stars, which were selected from their position on the colour-magnitude diagram, were almost all CN weak. This is in contrast to the red giant branch where a large minority were CN strong. The results were also compared with cluster formation and evolution models. Overall, this study shows that statistically significant elemental and evolutionary conclusions can be obtained from lower resolution spectroscopy. [ABSTRACT FROM AUTHOR]

ABSTRACT We present the mode identification of frequencies found in spectroscopic observations of the γ Doradus star HD 135825. Four frequencies were successfully identified: 1.3150 ± 0.0003, 0.2902 ± 0.0004, 1.4045 ± 0.0005 and 1.8829 ± 0.0005 d−1. These correspond to ( l, m) modes of (1, 1), (2, −2), (4, 0) and (1, 1), respectively. Additional frequencies were found but they were below the signal-to-noise ratio limit of the Fourier spectrum and not suitable for mode identification. The rotational axis inclination and v sin i of the star were determined to be 87° (nearly edge-on) and 39.7 km s−1 (moderate for γ Doradus stars), respectively. A simultaneous fit of these four modes to the line profile variations in the data gives a reduced χ2 of 12.7. We confirm, based on the frequencies found, that HD 135825 is a bona fide γ Doradus star. [ABSTRACT FROM AUTHOR]

ABSTRACT Gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. Mode identification will improve the knowledge of these stars considerably and allow an understanding of the issues with current pulsational models. A frequency analysis followed by a mode identification were done based on the high-resolution spectroscopic data of two γ Doradus stars: HD 189631 and HD 40745. Extensive spectroscopic data sets are obtained by three instruments: HARPS, FEROS and HERCULES. We obtained 422 spectra for HD 189631 and 248 spectra for HD 40745. The pulsational frequencies were determined by four methods: analysis of the variation in equivalent width, variation in radial velocity, asymmetry of the line profile and the pixel-by-pixel frequency analysis. The mode identification was done using the recently developed Fourier Parameter Fit method. Without achieving the same degree of confidence for all results, we report the identification of four pulsational modes in HD 189631: ( ℓ= 1; m =+1) at f1= 1.67 d−1; (3; −2) at f2= 1.42 d−1; (2; −2) at f3= 0.07 d−1; and (4; +1) at f4= 1.82 d−1; and two modes in HD 40745: (2; −1) at f1= 0.75 d−1 and (3; −3) at f2= 1.09 d−1. This study provides the first pulsational analysis based on spectroscopy of HD 189631 and HD 40745. We discuss the performance of current methods of analysis and outline the difficulties presented by γ Doradus stars. [ABSTRACT FROM AUTHOR]

Giant branch stars in the globular clusters NGC 362 and NGC 6388 were analysed for key s- and r-process element abundances. The NGC 362 stars showed comparable enhancements in the light and heavy s-process elements for the sample of 13 giant stars with values of dex and dex. The small spread in these values, as well as in the derived metallicity values ( dex), confirms the homogeneity of these elements in NGC 362. The two stars analysed in NGC 6388 showed enhancements in the light and heavy s-process elements with values of dex and dex. The light s-process elements are more enhanced in this metal-rich cluster compared to the heavy s-process elements. The derived metallicity was in good agreement between the two stars with the mean value for the cluster of dex. Due to the similar metallicity of NGC 6388 with 47 Tuc, these two stars were compared with the results from Worley et al. where giant branch stars in 47 Tuc were analysed. The heavy element enhancements between the two clusters were found to be very similar indicating that the relative enhancements of l s and h s elemental abundances is metallicity dependent. When comparing the three clusters, there is a distinct trend of decreasing l s abundance with decreasing metallicity. The h s abundances are essentially the same within their respective uncertainties. This is reflected in the [h s/l s] ratio for the three clusters. The ratio is very similar for NGC 6388 and 47 Tuc ( dex and dex, respectively), but for NGC 362 the ratio is much higher ( dex). The small spread of derived neutron-capture elemental abundance values for all three clusters confirms that these asymptotic giant branch stars are not undergoing third dredge-up and so are not producing the observed s-process enhancements internally. [ABSTRACT FROM AUTHOR]

We are undertaking an extensive observational campaign of a number of non-radially pulsating stars using the high-resolution HERCULES spectrograph on the 1.0-m telescope at the Mt John University Observatory. This is part of a large world-wide multi-site campaign to improve mode-identification techniques in non-radially pulsating stars, particularly for g-mode pulsators. This paper outlines our campaign and presents preliminary results for one γ Doradus star, HD 40745, and one β Cephei star, HD 61068. We have used a representative cross-correlation line-profile technique presented by Wright in 2008 to extract line profiles and these have then been analyzed using the FAMIAS package due to Zima published in 2006 to derive a spectroscopic mode identification. [ABSTRACT FROM AUTHOR]

The exploration of chemical abundances in globular cluster giant branch stars has revealed element-abundance inhomogeneities between the stars. This study has investigated a sample of giant branch stars in the globular cluster 47 Tucanæ, which were observed at a resolution of using the Ultraviolet Échelle Spectrograph on the Very Large Telescope. The analysis of these stars showed non-local thermodynamic equilibrium (non-LTE) effects on the abundances derived from the sample of atomic lines under an LTE approximation. The stellar parameters for each star were redetermined using only high-excitation-potential Fe i lines. The resulting chemical abundance analysis showed enhancements in both the light and heavy s-process element abundances with mean values of dex and dex. However, no trend was found between the ratio of the heavy to light s-process element abundances ([h s/l s] dex) and metallicity due to the small spread in both of these values. This indicates that the heavy-element-abundance enhancements are not due to third dredge-up of internal nucleosynthesis products in these evolved stars. The source of the heavy-element enhancements is therefore primordial or pollution event related in origin. [ABSTRACT FROM AUTHOR]

This study resolves a discrepancy in the abundance of Zr in the 47 Tucanæ asymptotic giant branch (AGB) star Lee 2525. This star was observed using the echelle spectrograph on the 2.3-m telescope at Siding Spring Observatory. The analysis was undertaken by calibrating Lee 2525 with respect to the standard giant star Arcturus. This work emphasizes the importance of using a standard star with stellar parameters comparable to the star under analysis rather than a calibration with respect to the Sun as in Koch & McWilliam . Systematic errors in the analysis process are then minimized due to the similarity in atmospheric structure between the standard and programme stars. The abundances derived for Lee 2525 were found to be in general agreement with the Brown & Wallerstein values except for Zr. In this study Zr has a similar enhancement ( dex) to another light s-process element, Y ( dex), which reflects current theory regarding the enrichment of s-process elements by nuclear processes within AGB stars. This is contrary to the results of Brown & Wallerstein where Zr was underabundant ( dex) and Y was overabundant ( dex) with respect to Fe. [ABSTRACT FROM AUTHOR]

We present results from a three-site photometric and high-resolution spectroscopic campaign on the hottest known extreme helium star V2076 Oph (HD 160641). A core programme of intensive observations covered two weeks and a much lower sampling rate extended over another two months. Despite the fact that the data seem to indicate periodicity near half a day (though the light curves are clearly not formed by a single periodicity), conventional Fourier analysis of the data fails to reveal coherent frequencies. Furthermore, we are unable to recover frequencies which were apparently clear in an earlier campaign on the star. Evidence of monotonic pulsation amplitude changes is seen at the higher frequencies from a wavelet analysis, but more data are needed before this study can be extended to lower frequencies. The application of linear stochastic differential equation (LSDE) methods indicates that the observed light variations could be a result of random variations giving the appearance of intermittent periodicity. High-resolution spectroscopic observations were obtained during the campaign and additional observations were made three years later. Complex line profile variations were observed. It is proposed that the different behaviour of the emission line studied may indicate it is associated with a stellar wind or resident circumstellar material. The frequencies that are extracted from the velocity data do not conform to those identified in the current or previous photometric campaigns. [ABSTRACT FROM AUTHOR]

We present high-resolution spectroscopic observations and species-by-species radial velocities of a number of southern Cepheids. The stars (BP Cir, V350 Sgr, AX Cir, V636 Sco, W Sgr, S Mus, β Dor, TT Aql, Y Oph, YZ Car, SW Vel, X Pup, T Mon and l Car) were observed as part of a long-term programme at Mt John University Observatory. Radial velocities were determined with the line bisector technique, and have a precision of ∼300 m s−1. Velocity differences as large as 30 km s−1 were found for Hα and Ca ii when referenced to the metallic line velocity curves, but more subtle variations (of 1–2 km s−1) were also detected in many other species. Pulsational phase anticorrelations are found between lines of Si ii and Ba ii, confirming the propagation time delay between line-forming layers producing these two species. We find that the amplitude and phase differences between the various species increase with period. [ABSTRACT FROM AUTHOR]

In this paper we examine the problems of phasing using light curves and offer an alternate technique using the changes in acceleration to establish the zero point. We give astrophysical justification as to why this technique is useful and apply the technique to a selection of Type II Cepheids. We then examine some limitations of the technique which qualify its use. [ABSTRACT FROM AUTHOR]

High-resolution spectroscopic observations have been made of a number of southern Cepheids. The stars studied were part of a long-term programme to observe southern variable stars and to complete a data base of radial velocities over a long time interval. The radial velocities have a precision of ∼300 m s−1, allowing the detection of velocity differences of ∼1 km s−1 with confidence. Our new data provide a consistent set of data against which other sources of data can be compared. Masses were determined for two systems, the 9-d Cepheid S Mus and the 5-d Cepheid V350 Sgr . For another seven Cepheids (Y Car, YZ Car, AX Cir, BP Cir, V636 Sco, W Sgr and T Mon), new or improved orbital solutions were found. New results presented here include the first orbital solution for AX Cir, a completely revised orbital solution for YZ Car, which established its eccentricity and orbital motion, and a new pulsation period (2.398 19 d) for BP Cir. The pulsational mass determinations provide further confirmation of the convergence of mass determinations between dynamical and evolutionary methods. [ABSTRACT FROM AUTHOR]

Abstarct Photometry and low- to high-resolution spectroscopy have been obtained throughout the 1998 decline of V854 Centauri. This is the most complete coverage of a decline of this star. Various emission lines which are typical of an RCB decline have been observed. Their evolution is consistent with the classification into three groups according to the E[sub 1]/E[sub 2]/BL line-region model. However, some of the line characteristics indicate a different origin from that suggested by the model. The low-excitation sharp emission lines (E[sub 2] group), visible throughout the whole decline, show a blueshift of about 3 km s[sup -1] and a complex profile indicating a shell with its outer region expanding faster than the inner parts. The estimated position of this region is at about 3.5 R[sub *] , assuming the dust cloud condensation occurs at about 2 R[sub *] . The high-excitation lines of C i, O i and Mg i, classified as E[sub 1], exhibit a redshift of a few km s[sup -1] relative to the stellar velocity, indicating a possible photospheric origin. The broad lines (BL group) show a constant absolute flux throughout the decline phase and therefore the region of their origin does not seem to be affected or obscured by the dust cloud causing the decline. The high-velocity Na i D absorption components, at a velocity of about -400 km s[sup -1], show a constantly increasing blueshift interpreted as an acceleration of the gas associated with the dust cloud formation. [ABSTRACT FROM AUTHOR]

During the second half of the nineteenth century an important part of the mechanism of the export of British capital was the operations of the "Anglo-Foreign Banks." The foundation of such institutions was facilitated by the liberalization of English Company Law with regard to banks under, the Acts of 1858 and 1862. It has been held that the boom in the flotation of financial institutions, which occurred between 1862 and 1866, was a consequence of the latter Act but such a movement was already underway before the Act became operative in the November of 1862. The less onerous conditions of the 1862 Act as compared with those of 1858 probably added further momentum to such flotations. The importance of "Anglo-foreign" banks in the new financial issues are clear when it is realized that of the 28 banks publicly floated in 1863, 15 were to operate abroad either wholly or in part. This exaggerates the number of effective new institutions, however, since the figure is ex ante rather than ex post in nature; many of the flotations were purely speculative and failed within a year of coming into existence.

Reports on calculations and measurements of static noise margin, performance and leakage for 0.18 and 0.13-μ m ultra-low power static random-access memories cell designs. Discussion on static noise margin; Cell leakage, cell performance and threshold voltage uncertainty.

We carried out an extensive photometric and spectroscopic investigation of the SPB binary, HD 25558 (see Fig. 1 for the time and geographic distribution of the observations). The ~2000 spectra obtained at 13 observatories during 5 observing seasons, the ground-based multi-colour light curves and the photometric data from the MOST satellite revealed that this object is a double-lined spectroscopic binary with a very long orbital period of about 9 years. We determined the physical parameters of the components, and have found that both lie within the SPB instability strip. Accordingly, both components show line-profile variations consistent with stellar pulsations. Altogether, 11 independent frequencies and one harmonic frequency were identified in the data. The observational data do not allow the inference of a reliable orbital solution, thus, disentangling cannot be performed on the spectra. Since the lines of the two components are never completely separated, the analysis is very complicated. Nevertheless, pixel-by-pixel variability analysis of the cross-correlated line profiles was successful, and we were able to attribute all the frequencies to the primary or secondary component. Spectroscopic and photometric mode-identification was also performed for several of these frequencies of both binary components. The spectroscopic mode-identification results suggest that the inclination and rotation of the two components are rather different. While the primary is a slow rotator with ~6 d rotation period, seen at ~60° inclination, the secondary rotates fast with ~1.2 d rotation period, and is seen at ~20° inclination. Our spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field was detected in the primary.The detailed analysis and results of this study will be published elsewhere. [ABSTRACT FROM PUBLISHER]

The gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. For the MUSICIAN programme at the University of Canterbury, we obtain extensive high-resolution echelle spectra of γ Dor stars from the Mt John University Observatory in New Zealand. We analyze these to obtain the pulsational frequencies and identify these with the multiple pulsational modes excited in the star. A summary of recent results from our spectroscopic mode-identification programme is given. [ABSTRACT FROM PUBLISHER]

Discusses the abstract of the study 'Knowledge and Attitudes of Modern Orthodox Jewish High School Students Toward Carrier Screening,' presented at the 21st Annual Education Conference of the National Society of Genetic Counselors held in Phoenix, Arizona in November 2002.