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3021. UV-to-FIR magnitudes for 83 starburst galaxies
ID:
ivo://CDS.VizieR/J/ApJS/143/377
Title:
UV-to-FIR magnitudes for 83 starburst galaxies
Short Name:
J/ApJS/143/377
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a database of UV-to-FIR data of 83 nearby starburst galaxies. The galaxies are selected based upon the availability of IUE data. We have recalibrated the IUE UV spectra for these galaxies by incorporating the most recent improvements. For 45 of these galaxies we use observations by Storchi-Bergmann et al. (1995ApJS...98..103S) and McQuade et al. (1995ApJS...97..331M) for the spectra in the optical range. The NIR data are from new observations obtained at the NASA/IRTF and the Mount Laguna Observatory, combined with the published results from observations at the Kitt Peak National Observatory. In addition, published calibrated ISO data are included to provide mid-IR flux densities for some of the galaxies. The optical-to-IR data are matched as closely as possible to the IUE large aperture. In conjunction with IRAS and ISO FIR flux densities, all these data form a set of observed spectral energy distributions (SEDs) of the nuclear regions of nearby starburst galaxies. The SEDs should be useful in studying star formation and dust/gas attenuation in galaxies. We also present the magnitudes in the standard BVRI and various HST/WFPC2 bandpasses synthesized from the UV and optical wavelength ranges of these SEDs. For some of the galaxies, the HST/WFPC2 magnitudes synthesized from the SEDs are checked with those directly measured from WFPC2 images to test the photometric errors of the optical data and their effective matching of apertures with the UV data. The implications of the new SEDs on the star formation rates and dust/gas attenuation are briefly discussed.
3022. UV to NIR obs. of SN 2019ehk
ID:
ivo://CDS.VizieR/J/ApJ/898/166
Title:
UV to NIR obs. of SN 2019ehk
Short Name:
J/ApJ/898/166
Date:
21 Mar 2022 09:18:33
Publisher:
CDS
Description:
We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in the star-forming galaxy M100 (d~16.2Mpc) starting 10hr after explosion and continuing for ~300days. SN 2019ehk shows a double-peaked optical light curve peaking at t=3 and 15days. The first peak is coincident with luminous, rapidly decaying Swift-XRT-discovered X-ray emission (L_x_~10^41^erg/s at 3days; Lx{propto}t^-3^), and a Shane/Kast spectral detection of narrow H{alpha} and HeII emission lines (v~500km/s) originating from pre-existent circumstellar material (CSM). We attribute this phenomenology to radiation from shock interaction with extended, dense material surrounding the progenitor star at r<10^15^cm and the resulting cooling emission. We calculate a total CSM mass of ~7x10^-3^M_{sun}_ (M_He_/M_H_~6) with particle density n~10^9^cm^-3^. Radio observations indicate a significantly lower density n<10^4^cm^-3^ at larger radii r>(0.1-1)x10^17^cm. The photometric and spectroscopic properties during the second light-curve peak are consistent with those of Ca-rich transients (rise-time of t_r_=13.4!+/-0.210days and a peak B-band magnitude of M_B_=-15.1+/-0.200mag). We find that SN 2019ehk synthesized (3.1+/-0.11)x10^-2^M_{sun}_ of ^56^Ni and ejected M_ej_=(0.72+/-0.040)M_{sun}_ total with a kinetic energy E_k_=(1.8+/-0.10)x10^50^erg. Finally, deep HST pre-explosion imaging at the SN site constrains the parameter space of viable stellar progenitors to massive stars in the lowest mass bin (~10M_{sun}_) in binaries that lost most of their He envelope or white dwarfs (WDs). The explosion and environment properties of SN 2019ehk further restrict the potential WD progenitor systems to low-mass hybrid HeCO WD+CO WD binaries.
3023. UV to NIR spectra of the QSO 2MASS J15165323+1900482
ID:
ivo://CDS.VizieR/J/ApJ/900/47
Title:
UV to NIR spectra of the QSO 2MASS J15165323+1900482
Short Name:
J/ApJ/900/47
Date:
21 Mar 2022 09:27:00
Publisher:
CDS
Description:
We present detailed studies of the partially obscured quasar 2MASSJ151653.23+190048.2 with continuous broadband spectrophotometry from near-infrared (NIR) through optical to ultraviolet (UV). The NIR and optical spectra show strong broad emission lines, while the UV spectrum is dominated by a set of rich intermediate-width emission lines (IELs). These IELs, unshifted with respect to the quasar systemic velocity measured by narrow emission lines, share a common profile of about 1900km/s in FWHM, in contrast to the Balmer and Paschen broad emission lines of FWHM ~6300km/s observed in the optical and NIR. The intermediate width of these lines indicates that the emitting gas may come from the dusty torus region. However, the observed peculiar IEL intensity ratios, such as NV{lambda}1240/Ly{alpha}, indicate that the emitting gas has a very high density, up to ~10^13^cm^-3^. Such a high density is unusual for gas around the dusty torus region, except that we consider mechanisms such as shocks that can produce local ultradense gas. We speculate that these emission lines could originate from the shock region, possibly induced by the quasar outflow colliding with the inner wall of the dusty torus. If true, this may give us an opportunity to peep at the quasar outflows at the scale of the dusty torus that have so far been elusive due to the limited resolving powers of existing facilities.
3024. UV to radio SED of galaxies in Virgo cluster
ID:
ivo://CDS.VizieR/J/A+A/402/37
Title:
UV to radio SED of galaxies in Virgo cluster
Short Name:
J/A+A/402/37
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a multifrequency dataset for an optically-selected, volume-limited, complete sample of 118 late-type galaxies (>=S0a) in the Virgo cluster. The database includes UV, visible, near-IR, mid-IR, far-IR, radio continuum photometric data as well as spectroscopic data of H{alpha}, CO and HI lines, homogeneously reduced, obtained from our own observations or compiled from the literature. Assuming the energy balance between the absorbed stellar light and that radiated in the IR by dust, we calibrate an empirical attenuation law suitable for correcting photometric and spectroscopic data of normal galaxies. The data, corrected for internal extinction, are used to construct the spectral energy distribution (SED) of each individual galaxy, and combined to trace the median SED of galaxies in various classes of morphological type and luminosity.
3025. UV variability of Fairall-9
ID:
ivo://CDS.VizieR/J/A+AS/121/461
Title:
UV variability of Fairall-9
Short Name:
J/A+AS/121/461
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a study of the UV variability of the galaxy Fairall-9 between 1978 and 1991. Table 1 shows the UV continuum fluxes measured in three "line-free" windows centered at 1171, 1400 and 1910 A (observed wavelengths), and corrected for E(B-V)=0.035 extinction. The IUE Fine Error Sensor (FES) counts (optical photometry) are also given in this table, corrected for the same extinction. Tables 10, 11, 12 and 13 show the variability of the components for the main UV lines (Ly{alpha}+NV, SiIV, CIV and MgII). Line profile variability has been used to isolate four gaussian line components, which are sufficient to describe all lines at all levels of brightness in a consistent way: one narrow (i.e. unresolved at the IUE resolution) and three broad components: a central (velocity same as the narrow line), a redshifted (v=3300 km/s) and a blue shifted one (v=-3600 km/s). The Ly{alpha}-NV blend is fitted together in the Ly{alpha} region (Table 10), to account the NV presence (one narrow and one red component). The results for SiIV are shown in Table 11. In CIV (Table 12) have been included a very weak component bluer than the blue component, most likely associated with NIV] 1486. Table 13 shows MgII results.
3026. Vacuum ultraviolet emission band systems of N2
ID:
ivo://CDS.VizieR/J/A+AS/128/361
Title:
Vacuum ultraviolet emission band systems of N2
Short Name:
J/A+AS/128/361
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observed wavenumbers of the emission lines belonging to 10 vacuum ultraviolet band systems of molecular nitrogen are classified into 283 bands, 220 of them reported for the first time
3027. 44 validated planets from K2 Campaign 10
ID:
ivo://CDS.VizieR/J/AJ/156/78
Title:
44 validated planets from K2 Campaign 10
Short Name:
J/AJ/156/78
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 44 validated planets from the 10th observing campaign of the NASA K2 mission, as well as high-resolution spectroscopy and speckle imaging follow-up observations. These 44 planets come from an initial set of 72 vetted candidates, which we subjected to a validation process incorporating pixel-level analyses, light curve analyses, observational constraints, and statistical false positive probabilities. Our validated planet sample has median values of R_p_=2.2 R_{Earth}_, P_orb_=6.9 days, T_eq_=890 K, and J=11.2 mag. Of particular interest are four ultra-short period planets (P_orb_~<1 day), 16 planets smaller than 2 R_{Earth}_, and two planets with large predicted amplitude atmospheric transmission features orbiting infrared-bright stars. We also present 27 planet candidates, most of which are likely to be real and worthy of further observations. Our validated planet sample includes 24 new discoveries and has enhanced the number of currently known super-Earths (R_p_~1-2 R_{Earth}_), sub-Neptunes (R_p_~2-4 R_{Earth}_), and sub-Saturns (R_p_~4-8 R_{Earth}_) orbiting bright stars (J=8-10 mag) by ~4%, ~17%, and ~11%, respectively.
3028. Vanadium log(gf) and transition probabilities
ID:
ivo://CDS.VizieR/J/ApJS/215/20
Title:
Vanadium log(gf) and transition probabilities
Short Name:
J/ApJS/215/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
New emission branching fraction measurements for 836 lines of the first spectrum of vanadium (VI) are determined from hollow cathode lamp spectra recorded with the National Solar Observatory 1m Fourier transform spectrometer (FTS) and a high-resolution echelle spectrometer. The branching fractions are combined with recently published radiative lifetimes from laser-induced fluorescence measurements to determine accurate absolute atomic transition probabilities for the 836 lines. The FTS data are also used to extract new hyperfine structure A coefficients for 26 levels of neutral vanadium. These new laboratory data are applied to determine the V abundance in the Sun and metal-poor star HD 84937, yielding log{epsilon}(V)=3.956+/-0.004 ({sigma}=0.037) based on 93 VI lines and log{epsilon}(V)=1.89+/-0.03 ({sigma}=0.07) based on nine VI lines, respectively, using the Holweger-Muller 1D model. These new VI abundance values for the Sun and HD 84937 agree well with our earlier determinations based upon VII.
3029. Vanadium measurements for 135 M dwarfs
ID:
ivo://CDS.VizieR/J/A+A/654/A118
Title:
Vanadium measurements for 135 M dwarfs
Short Name:
J/A+A/654/A118
Date:
22 Feb 2022
Publisher:
CDS
Description:
M-dwarf spectra are complex and notoriously difficult to model, posing challenges to understanding their photospheric properties and compositions in depth. Vanadium (V) is an iron-group element whose abundance supposedly closely tracks that of iron, but has origins that are not completely understood. Our aim is to characterize a series of neutral vanadium atomic absorption lines in the 800-910nm wavelength region of high signal-to-noise, high-resolution, telluric-corrected M-dwarf spectra from the CARMENES survey. Many of these lines are prominent and exhibit a distinctive broad and flat-bottom shape -- a result of hyperfine splitting (HFS). We investigate the potential and implications of these HFS-split lines for abundance analysis of cool stars. With standard spectral synthesis routines, as provided by the spectroscopy software iSpec and the latest atomic data (including HFS) available from the VALD3 database, we model these striking line profiles. We use them to measure V abundances of cool dwarfs. We determine V abundances for 135 early-M dwarfs (M0.0V to M3.5V) in the CARMENES guaranteed time observations sample. They exhibit a [V/Fe]-[Fe/H] trend consistent with that derived from nearby FG dwarfs. The tight (+/-0.1dex) correlation between [V/H] and [Fe/H] suggests the potential application of V as an alternative metallicity indicator in M dwarfs. We also show hints that a neglect to model HFS could partially explain the temperature correlation in V abundance measurements observed in previous studies of samples involving dwarf stars with Teff<=5300K. Our work suggests that HFS can impact certain absorption lines in cool photospheres more severely than in Sun-like ones. Therefore, we advocate that HFS should be carefully treated in abundance studies in stars cooler than ~5000 K. On the other hand, strong HFS split lines in high-resolution spectra present an opportunity for precision chemical analyses of large samples of cool stars. The V-to-Fe trends exhibited by the local M dwarfs continue to challenge theoretical models of V production in the Galaxy.
3030. Vanadium transitions in the spectrum of Arcturus
ID:
ivo://CDS.VizieR/J/ApJS/234/25
Title:
Vanadium transitions in the spectrum of Arcturus
Short Name:
J/ApJS/234/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive a new abundance for vanadium in the bright, mildly metal-poor red giant Arcturus. This star has an excellent high-resolution spectral atlas and well-understood atmospheric parameters, and it displays a rich set of neutral vanadium lines that are available for abundance extraction. We employ a newly recorded set of laboratory FTS spectra to investigate any potential discrepancies in previously reported V I log(gf) values near 900nm. These new spectra support our earlier laboratory transition data and the calibration method utilized in that study. We then perform a synthetic spectrum analysis of weak V I features in Arcturus, deriving log{epsilon}(V)=3.54+/-0.01 ({sigma}=0.04) from 55 lines. There are no significant abundance trends with wavelength, line strength, or lower excitation energy.

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