Search

Start Over Subject spectroscopy
2711. SPT-S J041839-4751.8 APEX spectra
ID:
ivo://CDS.VizieR/J/A+A/631/A167
Title:
SPT-S J041839-4751.8 APEX spectra
Short Name:
J/A+A/631/A167
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of six far-infrared fine structure lines in the z=4.225 lensed dusty star-forming galaxy SPT 0418-47 (SPT-S J041839-4751.8) to probe the physical conditions of its inter stellar medium (ISM). In particular, we report Atacama Pathfinder EXperiment (APEX) detections of the [OI] 145um and [OIII] 88um lines and Atacama Compact Array (ACA) detections of the [NII] 122 and 205um lines. The [OI] 145um/[CII] 158um line ratio is ~5x higher compared to the average of local galaxies. We interpret this as evidence that the ISM is dominated by photo-dissociation regions with high gas densities. The line ratios, and in particular those of [OIII] 88um and [NII] 122um imply that the ISM in SPT 0418-47 is already chemically enriched to nearly solar metallicity. While the strong gravitational amplification was required to detect these lines with APEX, larger samples can be observed with the Atacama Large Millimeter/submillimeter Array (ALMA), and should allow observers to determine if the dense, solar metallicity ISM is common among these highly star-forming galaxies.
2712. SPT-SZ survey galaxy clusters optical spectroscopy
ID:
ivo://CDS.VizieR/J/ApJ/792/45
Title:
SPT-SZ survey galaxy clusters optical spectroscopy
Short Name:
J/ApJ/792/45
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical spectroscopy of galaxies in clusters detected through the Sunyaev-Zel'dovich (SZ) effect with the South Pole Telescope (SPT). We report our own measurements of 61 spectroscopic cluster redshifts, and 48 velocity dispersions each calculated with more than 15 member galaxies. This catalog also includes 19 dispersions of SPT-observed clusters previously reported in the literature. The majority of the clusters in this paper are SPT-discovered; of these, most have been previously reported in other SPT cluster catalogs, and five are reported here as SPT discoveries for the first time. By performing a resampling analysis of galaxy velocities, we find that unbiased velocity dispersions can be obtained from a relatively small number of member galaxies (<~ 30), but with increased systematic scatter. We use this analysis to determine statistical confidence intervals that include the effect of membership selection. We fit scaling relations between the observed cluster velocity dispersions and mass estimates from SZ and X-ray observables. In both cases, the results are consistent with the scaling relation between velocity dispersion and mass expected from dark-matter simulations. We measure a ~30% log-normal scatter in dispersion at fixed mass, and a ~10% offset in the normalization of the dispersion-mass relation when compared to the expectation from simulations, which is within the expected level of systematic uncertainty.
2713. SSHADE bandlist library
ID:
ivo://osug-vo.osug/sshade_bandlist/q/epn_core
Title:
SSHADE bandlist library
Short Name:
SSHADE Bandlist
Date:
10 Jun 2024 06:48:51
Publisher:
OSUG Virtual Observatory
Description:
SSHADE bandlist library.
2714. SSHADE spectra library
ID:
ivo://osug-vo.osug/sshade_spectra/q/epn_core
Title:
SSHADE spectra library
Short Name:
SSHADE Spectra
Date:
10 Jun 2024 06:48:37
Publisher:
OSUG Virtual Observatory
Description:
SSHADE spectra library.
2715. SSHADE spectra library
ID:
ivo://osug-vo.osug/sshade_spectra/q/import
Title:
SSHADE spectra library
Date:
20 Jan 2022 15:42:21
Publisher:
OSUG Virtual Observatory
Description:
SSHADE spectra library.
2716. SSHADE spectra library (dev)
ID:
ivo://osug-vo.osug/dev_sshade_spectra/q/epn_core
Title:
SSHADE spectra library (dev)
Date:
21 Jan 2022 11:13:37
Publisher:
OSUG Virtual Observatory
Description:
SSHADE spectra library.
2717. SSHADE spectra library (dev)
ID:
ivo://osug-vo.osug/dev_sshade_spectra/q/import
Title:
SSHADE spectra library (dev)
Date:
21 Jan 2022 10:51:59
Publisher:
OSUG Virtual Observatory
Description:
SSHADE spectra library.
2718. Ssynthetic spectra of supernovae models
ID:
ivo://CDS.VizieR/J/A+A/621/A109
Title:
Ssynthetic spectra of supernovae models
Short Name:
J/A+A/621/A109
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observational surveys are now able to detect an increasing number of transients, such as core-collapse supernovae (SN) and powerful non-terminal outbursts (SN impostors). Dedicated spectroscopic facilities can follow up these events shortly after detection. Here we investigate the properties of these explosions at early times.We use the radiative transfer code CMFGEN to build an extensive library of spectra simulating the interaction of supernovae and their progenitor's winds/circumstellar medium (CSM).We consider a range of progenitor mass-loss rates (dM/dt=5x10^-4^ to 10^-2^ M_{sun}/yr), abundances (solar, CNO-processed, and He-rich), and SN luminosities (L=1.9x10^8^ to 2.5x10^10^L_{sun}_). The models simulate events ~=1-day after explosion, and we assume a fixed location of the shock front as R_in_=8.6x10^13^cm. We show that the large range of massive star properties at the pre-SN stage causes a diversity of early-time interacting SN and impostors. We identify three main classes of early-time spectra consisting of relatively high-ionisation (e.g. HeII and OVI), medium-ionisation (e.g. CIII and NIII), and low-ionisation lines (e.g. HeI and FeII/III). They are regulated by L and the CSM density. Given a progenitor wind velocity v_inf_, our models also place a lower limit of dM/dt>~5x10^-4^(v_inf_=150km/s)M_{sun}_/yr for detection of CSM interaction signatures in observed spectra. Early-time SN spectra should provide clear constraints on progenitors by measuring H, He, and CNO abundances if the progenitors come from single stars. The connections are less clear considering the effects of binary evolution. Nevertheless, our models provide a clear path for linking the final stages of massive stars to their post-explosion spectra at early times, and guiding future observational follow-up of transients with facilities such as the Zwicky Transient Facility.
2719. Stacked spectra of SDSS star forming galaxies
ID:
ivo://CDS.VizieR/J/ApJ/765/140
Title:
Stacked spectra of SDSS star forming galaxies
Short Name:
J/ApJ/765/140
Date:
21 Oct 2021
Publisher:
CDS
Description:
The relation between galaxy stellar mass and gas-phase metallicity is a sensitive diagnostic of the main processes that drive galaxy evolution, namely cosmological gas inflow, metal production in stars, and gas outflow via galactic winds. We employed the direct method to measure the metallicities of ~200000 star-forming galaxies from the Sloan Digital Sky Survey that were stacked in bins of (1) stellar mass and (2) both stellar mass and star formation rate (SFR) to significantly enhance the signal-to-noise ratio of the weak [OIII]{lambda}4363 and [OII]{lambda}{lambda}7320,7330 auroral lines required to apply the direct method. These metallicity measurements span three decades in stellar mass from log(M_*_/M_{sun}_)=7.4-10.5, which allows the direct method mass-metallicity relation to simultaneously capture the high-mass turnover and extend a full decade lower in mass than previous studies that employed more uncertain strong line methods. The direct method mass-metallicity relation rises steeply at low mass (O/H{prop.to}M_*_^1/2^) until it turns over at log(M_*_/M_{sun}_)=8.9 and asymptotes to 12+log(O/H)=8.8 at high mass. The direct method mass-metallicity relation has a steeper slope, a lower turnover mass, and a factor of two to three greater dependence on SFR than strong line mass-metallicity relations. Furthermore, the SFR-dependence appears monotonic with stellar mass, unlike strong line mass-metallicity relations. We also measure the N/O abundance ratio, an important tracer of star formation history, and find the clear signature of primary and secondary nitrogen enrichment. N/O correlates tightly with oxygen abundance, and even more so with stellar mass.
2720. Standard calibration stars infrared spectra
ID:
ivo://CDS.VizieR/J/AJ/132/1445
Title:
Standard calibration stars infrared spectra
Short Name:
J/AJ/132/1445
Date:
21 Oct 2021
Publisher:
CDS
Description:
Infrared spectra with increased spectral resolution and accuracy of the absolute infrared spectral flux have been created for a subset of stellar standards created by Cohen and his collaborators in previous papers in this series. Moderate-resolution ({lambda}/{Delta}{lambda}~400) spectroscopy obtained on infrared standard stars by the Short Wavelength Spectrometer on the Infrared Space Observatory was combined with high-quality photometry tied to our recent absolute calibration from the Midcourse Space Experiment. Thus, 1-35 micron spectra were created for 33 stars, 9 of which are Cohen et al. secondary standards and another 20 of which are tertiary standards for which Cohen adopted spectral templates. The wavelength spacing is given by (0.0001/1 micron)*lambda^2, which provides for 10,000 samples over the 1-35 micron spectral range

Limit your search

more »

more »

more »

more »

more »