- ID:
- ivo://CDS.VizieR/J/MNRAS/496/2422
- Title:
- Abundances of 42 Pisces-Eridanus stream stars
- Short Name:
- J/MNRAS/496/2422
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recently, a new cylindrical-shaped stream of stars, up to 700pc long, was discovered hiding in the Galactic disk using kinematic data enabled by the Gaia mission. This curious stream of stars, dubbed the Pisces-Eridanus stream, was initially thought to be as old as 1Gyr, yet its stars shared a rotation period distribution consistent with the 120-Myr-old Pleiades cluster. In this work, we explore the detailed chemical nature of this stellar stream. We carried out high-resolution spectroscopic follow-up of 42 Pisces-Eridanus stream stars using McDonald Observatory, and combined these data with information for 40 members observed with the low-resolution LAMOST spectroscopic survey. Together, these data enabled us to measure the abundance distribution of light/odd-Z (Li, C, Na, Al, Sc, V), {alpha} (Mg, Si, Ca, Ti), Fe-peak (Cr, Mn, Fe, Co, Ni, Zn), and neutron capture (Sr, Y, Zr, Ba, La, Nd, Eu) elements across the Pisces-Eridanus stream. We find that the stream is (1) near solar metallicity with [Fe/H] = -0.03 dex and (2) has a metallicity spread of 0.07 dex (or 0.04 dex when removing outliers). We also find that (3) the abundance of Li indicates that Pisces-Eridanus is ~120Myr old, consistent with the gyrochronology result. We find that (4) the stream has a [X/Fe] abundance spreads of 0.06<{sigma}_[X/Fe]_<0.20dex in most elements, and (5) no significant abundance gradients across its major axis except a potentially weak gradient in [Si/Fe]. These results together show that the Pisces-Eridanus stream is a uniquely close, young, chemically interesting laboratory for testing our understanding of star and planet formation.
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- ID:
- ivo://CDS.VizieR/J/ApJ/765/157
- Title:
- Abundances of red giants in the Galactic bulge
- Short Name:
- J/ApJ/765/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radial velocities and chemical abundance ratios of [Fe/H], [O/Fe], [Si/Fe], and [Ca/Fe] for 264 red giant branch stars in three Galactic bulge off-axis fields located near (l,b)=(-5.5,-7), (-4,-9), and (+8.5,+9). The results are based on equivalent width and spectrum synthesis analyses of moderate resolution (R{approx}18000), high signal-to-noise ratio (S/N~75-300pixel^-1^) spectra obtained with the Hydra spectrographs on the Blanco 4m and WIYN 3.5m telescopes. The targets were selected from the blue side of the giant branch to avoid cool stars that would be strongly affected by CN and TiO; however, a comparison of the color-metallicity distribution in literature samples suggests that our selection of bluer targets should not present a significant bias against metal-rich stars.
- ID:
- ivo://CDS.VizieR/J/AJ/157/154
- Title:
- Abundances of RGs in Galactic globular clusters
- Short Name:
- J/AJ/157/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Among stars in Galactic globular clusters the carbon abundance tends to decrease with increasing luminosity on the upper red giant branch, particularly within the lowest metallicity clusters. While such a phenomena is not predicted by canonical models of stellar interiors and evolution, it is widely held to be the result of some extra mixing operating during red giant branch ascent which transports material exposed to the CN(O)-cycle across the radiative zone in the stellar interior and into the base of the convective envelope, whereupon it is brought rapidly to the stellar surface. Here we present measurements of [C/Fe] abundances among 67 red giants in 19 globular clusters within the Milky Way. Building on the work of Martell et al. (2008AJ....136.2522M), we have concentrated on giants with absolute magnitudes of M_V_~-1.5 within clusters encompassing a range of metallicity (-2.4<[Fe/H]<-0.3). The Kitt Peak National Observatory (KPNO) 4 m and Southern Astrophysical Research (SOAR) 4.1 m telescopes were used to obtain spectra covering the {lambda}4300 CH and {lambda}3883 CN bands. The CH absorption features in these spectra have been analyzed via synthetic spectra in order to obtain [C/Fe] abundances. These abundances and the luminosities of the observed stars were used to infer the rate at which C abundances change with time during upper red giant branch evolution (i.e., the mixing efficiency). By establishing rates over a range of metallicity, the dependence of deep mixing on metallicity is explored. We find that the inferred carbon depletion rate decreases as a function of metallicity, although our results are dependent on the initial [C/Fe] composition assumed for each star.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A81
- Title:
- Abundances of 72 solar-type stars
- Short Name:
- J/A+A/640/A81
- Date:
- 29 Nov 2021 07:35:20
- Publisher:
- CDS
- Description:
- Previous high-precision studies of abundances of elements in solar twin stars are extended to a wider metallicity range to see how the trends of element ratios with stellar age depend on [Fe/H]. HARPS spectra with S/N>~600 at {lambda}~6000{AA} were analysed with MARCS model atmospheres to obtain 1D LTE abundances of C, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Sr, and Y in 72 solar-type stars including the binary star zeta Reticuli and ASTEC stellar models were used to determine stellar ages from effective temperatures, luminosities obtained via Gaia DR2 parallaxes, and heavy element abundances. The age-metallicity distribution appears to consist of the following two distinct populations: a sequence of old stars with a steep rise of [Fe/H] to ~+0.3 dex at an age of ~7Gyr and a younger sequence with [Fe/H] increasing from about -0.3dex to ~+0.2dex over the last 6Gyr. Furthermore, the trends of several abundance ratios, [O/Fe], [Na/Fe], [Ca/Fe], and [Ni/Fe], as a function of stellar age, split into two corresponding sequences. The [Y/Mg]-age relation, on the other hand, shows no offset between the two age sequences and has no significant dependence on [Fe/H], but the components of a visual binary star, {zeta} Reticuli, have a large and puzzling deviation. The split of the age-metallicity distribution into two sequences may be interpreted as evidence of two episodes of accretion of gas onto the Galactic disk with a quenching of star formation in between. Some of the [X/Fe]-age relations support this scenario but other relations are not so easy to explain, which calls for a deeper study of systematic errors in the derived abundances as a function of [Fe/H], in particular 3D non-LTE effects.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1542
- Title:
- A catalog of MIPSGAL disk and ring sources
- Short Name:
- J/AJ/139/1542
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 416 extended, resolved, disk and ringlike objects as detected in the MIPSGAL 24um survey of the Galactic plane. This catalog is the result of a search in the MIPSGAL image data for generally circularly symmetric, extended "bubbles" without prior knowledge or expectation of their physical nature. Most of the objects have no extended counterpart at 8um or 70um, with less than 20% detections at each wavelength. For the 54 objects with central point sources, the sources are nearly always seen in all Infrared Array Camera bands. About 70 objects (16%) have been previously identified, with another 35 listed as Infrared Astronomical Satellite sources.
- ID:
- ivo://CDS.VizieR/VII/187
- Title:
- A Catalogue of Galactic Supernova Remnants
- Short Name:
- VII/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog lists all galactic supernova remnants known and is the July 1995 updated version of the catalogues of Galactic SNRs presented in detail in Green (1984, 1988) and in summary form in Green (1991,1996). The basic parameters of the 194 SNRs included in this (1995 July) version of the catalogue are, for each SNR, its Galactic coordinates, RA and Dec (B1950.0), angular size (in arcmin), type, flux density at 1 GHz, spectral index, and any other names. Notes on these parameters, on possible remnants not included and questionable SNRs listed in the catalogue are given in the documentation. It should be noted that there are serious selection effects which apply to the identification of Galactic SNRs (see Green 1991), so that great care should be taken if these data are used in statistical studies.
- ID:
- ivo://CDS.VizieR/VII/210
- Title:
- A Catalogue of Galactic Supernova Remnants
- Short Name:
- VII/210
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog of known Galactic supernova remnants (SNRs) is an updated version (Version VI, August 1996) of the catalogs of Galactic SNRs presented in detail in Green (Version I 1984, Version II 1988), in summary form in Green (Version III 1991, Version IV 1996), and on the Web (Version V, July 1995). (Note that Version IV, although published in 1996, was producted in 1993.) This August 1996 version of the catalog contains 215 SNRs, which is 21 more than listed in the previous version. The basic summary data included in this catalog for each SNR are its Galactic coordinates, RA and Dec (B1950.0), angular size (in arcmin), type, flux density at 1 GHz, spectral index, and any other names. Notes on these parameters, on possible remnants not included, and questionable SNRs listed in the catalog are given in the documentation file (snrs.doc). It should be noted that there are serious selection effects which apply to the identification of Galactic SNRs (see Green 1991), so that great care should be taken if these data are used in statistical studies.
- ID:
- ivo://CDS.VizieR/VII/227
- Title:
- A Catalogue of Galactic Supernova Remnants
- Short Name:
- VII/227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue of known Galactic supernova remnants (SNRs) is an updated version of the catalogues of Galactic SNRs presented in detail in Green (1984, 1988), in summary form in Green (1991, 1996), and on the World-Wide-Web (versions of 1995 July 1995, 1996 August, 1998 September, and 2000 August). (Note that version published in Green (1996) was produced in 1993.) This 2001 December version of the catalogue contains 231 SNRs, which is 6 more than listed in the previous version. The basic summary data included in this catalogue for each SNR are its Galactic coordinates, RA and Dec (J2000.0), angular size (in arcmin), type, flux density at 1 GHz, spectral index, and any other names. Notes on these parameters, on possible remnants not included, and questionable SNRs listed in the catalogue are given in the full version of the catalogue on the World-Wide-Web. It should be noted that there are serious selection effects which apply to the identification of Galactic SNRs (see Green 1991), so that great care should be taken if these data are used in statistical studies.
- ID:
- ivo://CDS.VizieR/VII/278
- Title:
- A Catalogue of Galactic Supernova Remnants
- Short Name:
- VII/278
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue of known Galactic supernova remnants (SNRs) is an updated version of the catalogues of Galactic SNRs presented in detail in Green (1984, 1988), in summary form in Green (1991, 1996, 2004, 2009, 2014), and on the Web (versions of 1995 July, 1996 August, 1998 September, 2000 August, 2001 December, 2004 January and 2006 April). (Note that version published in Green (1996) was produced in 1993.) This the 2017 June version of the catalogue contains 295 SNRs, and is based on results published in the literature up to the end of 2016. The basic summary data included in this catalogue for each SNR are its Galactic coordinates, RA and Dec (J2000.0), angular size, type, flux density at 1 GHz, spectral index, and any other names. Notes on these parameters, on possible remnants not included, and questionable SNRs listed in the catalogue are given in the full version of the catalogue on the Web. It should be noted that there are selection effects which apply to the identification of Galactic SNRs (e.g., Green 1991, 2004, 2005, 2009), so that care should be taken if these data are used in any statistical studies.
- ID:
- ivo://CDS.VizieR/VII/272
- Title:
- A catalogue of Galactic supernova remnants
- Short Name:
- VII/272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue of known Galactic supernova remnants (SNRs) is an updated version of the catalogues of Galactic SNRs presented in detail in Green (1984, 1988), in summary form in Green (1991, 1996, 2004, 2009), and on the Web (versions of 1995 July, 1996 August, 1998 September, 2000 August, 2001 December, 2004 January and 2006 April). (Note that version published in Green (1996) was produced in 1993.) This the 2014 May version of the catalogue contains 294 SNRs, and is based on results published in the literature up to the end of 2013. The basic summary data included in this catalogue for each SNR are its Galactic coordinates, RA and Dec (J2000.0), angular size, type, flux density at 1GHz, spectral index, and any other names. Notes on these parameters, on possible remnants not included, and questionable SNRs listed in the catalogue are given in the full version of the catalogue on the Web. It should be noted that there are selection effects which apply to the identification of Galactic SNRs (e.g., Green 1991, 2004, 2005, 2009), so that care should be taken if these data are used in any statistical studies. Published in Green, D.A., 2014, BASI, 42, 47 (2014BASI...42...47G).
