- ID:
- ivo://CDS.VizieR/J/AZh/71/468
- Title:
- Spectrophotometric Standards near the Pole
- Short Name:
- J/AZh/71/468
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absolute energy distributions for 13 circumpolar ({delta}>+85deg) stars forming a spectrophotometric version of the North Polar Spectrophotometric Sequence (NPSS) are presented. A-type stars of 5-9mag brightness were studied in the range 3100 to 7750A with resolution of 50A. Observations were made with 0.5-m and 1-m telescopes using Seya-Namioka spectrometers. The relative rms error of results in the region 4000-7000A is 2 to 3%, while at the ends of the studied range it is 3-5%. The primary standard was the circumpolar star HD 221525 (V=5.58, A7IV), and its spectral energy distribution had been determined earlier.
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- ID:
- ivo://CDS.VizieR/J/ApJ/815/58
- Title:
- Spectrophotometric time series obs. of twin SNIa
- Short Name:
- J/ApJ/815/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce a method for identifying "twin" Type Ia supernovae (SNeIa) and using them to improve distance measurements. This novel approach to SN Ia standardization is made possible by spectrophotometric time series observations from the Nearby Supernova Factory (SNfactory). We begin with a well-measured set of SNe, find pairs whose spectra match well across the entire optical window, and then test whether this leads to a smaller dispersion in their absolute brightnesses. This analysis is completed in a blinded fashion, ensuring that decisions made in implementing the method do not inadvertently bias the result. We find that pairs of SNe with more closely matched spectra indeed have reduced brightness dispersion. We are able to standardize this initial set of SNfactory SNe to 0.083+/-0.012mag, implying a dispersion of 0.072+/-0.010mag in the absence of peculiar velocities. We estimate that with larger numbers of comparison SNe, e.g., using the final SNfactory spectrophotometric data set as a reference, this method will be capable of standardizing high-redshift SNe to within 0.06-0.07mag. These results imply that at least 3/4 of the variance in Hubble residuals in current SN cosmology analyses is due to previously unaccounted-for astrophysical differences among the SNe.
- ID:
- ivo://CDS.VizieR/J/ApJ/656/168
- Title:
- Spectrophotometry in NGC 5253
- Short Name:
- J/ApJ/656/168
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present echelle spectrophotometry of the blue compact dwarf galaxy NGC 5253 obtained with the VLT UVES. We have measured the intensities of a large number of permitted and forbidden emission lines in four zones of the central part of the galaxy. We detect faint CII and OII recombination lines, the first time that these are unambiguously detected in a dwarf starburst galaxy. The physical conditions of the ionized gas have been derived using a large number of different line intensity ratios.
- ID:
- ivo://CDS.VizieR/J/AJ/114/699
- Title:
- Spectrophotometry in open clusters
- Short Name:
- J/AJ/114/699
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectrophotometry is presented for 237 stars in 7 nearby open clusters: Hyades, Pleiades, Alpha Persei, Praesepe, Coma Berenices, IC 4665, and M39. The observations were taken by Lee McDonald and David Burstein using the Wampler single-channel scanner on the Crossley 0.9m telescope at Lick Observatory from 1973 July through 1974 December. Sixteen bandpasses spanning the spectral range 3500-7780{AA} were observed for each star, with bandwidths 32, 48, or 64{AA}. Data are standardized to the Hayes-Latham system to mutual accuracy of 0.016mag per passband. The accuracy of the spectrophotometry is assessed in three ways on a star-by-star basis. First, comparisons are made with previously published spectrophotometry for 19 stars observed in common. Second, (B-V) colors and uvby colors are compared for 236 stars and 221 stars, respectively. Finally, comparisons are made for 200 main sequence stars to the spectral synthesis models of Kurucz, fixing logg=4.0 and [Fe/H]=0.0, and only varying effective temperature. The accuracy of tests using uvby colors and the Kurucz models are shown to track each other closely, yielding an accuracy estimate (1{sigma}) of 0.01mag for the 13 colors formed from bandpasses longward of the Balmer jump, and 0.02mag for the 3 colors formed from the three bandpasses below the Balmer jump. In contrast, larger scatter is found relative to the previously published spectrophotometry of Bohm-Vitense & Johnson (1977ApJS...35..461B) (16 stars in common) and Gunn & Stryker (1983, Cat. <III/88>) (3 stars). We also show that the scatter in the fits of the spectrophotometric colors and the uvby filter colors is a reasonable way to identify the observations of which specific stars are accurate to 1{sigma}, 2{sigma}, .... As such, the residuals from both the filter color fits and the Kurucz model fits are tabulated for each star where it was possible to make a comparison, so users of these data can choose stars according to the accuracy of the data that is appropriate to their needs. The very good agreement between the models and these data verifies the accuracy of these data, and also verifies the usefulness of the Kurucz models to define spectrophotometry for stars in this temperature range (>5000K). These data define accurate spectrophotometry of bright, open cluster stars that can be used as a secondary flux calibration for CCD-based spectrophotometric surveys. (c) 1997 American Astronomical Society.
- ID:
- ivo://CDS.VizieR/J/ApJ/695/1591
- Title:
- Spectrophotometry in PEARS fields
- Short Name:
- J/ApJ/695/1591
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep ACS slitless grism observations and identification of stellar sources are presented within the Great Observatories Origins Deep Survey North and South fields which were obtained in the Probing Evolution And Reionization Spectroscopically (PEARS) program. It is demonstrated that even low-resolution spectra can be a very powerful means of identifying stars in the field, especially low-mass stars with stellar types M0 and later. The PEARS fields lay within the larger GOODS fields, and we used new, deeper images to further refine the selection of stars in the PEARS field, down to a magnitude of z_850_=25 using a newly developed stellarity parameter. The total number of stars with reliable spectroscopic and morphological identification was 95 and 108 in the north and south fields, respectively.
- ID:
- ivo://CDS.VizieR/J/AJ/130/23
- Title:
- Spectrophotometry of 3CR lobe-dominated quasars
- Short Name:
- J/AJ/130/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from optical spectrophotometry of 19 of the 25 lobe-dominated quasars in the 3CR complete sample. The optical spectra were obtained with the Hale 5m telescope at Palomar Observatory, using the blue and red CCDs of the Double Spectrograph, between 1984 and 1992. Additional data from the literature allow us to analyze broad UV/optical emission lines in all 25 objects (100% completeness), with a total of 191 broad-line measurements (far more than the 68 points in the preliminary results presented in the 2002 work of Hough et al., 2002AJ....123.1258H).
17217. Spectrophotometry of Mrk 509
- ID:
- ivo://CDS.VizieR/J/PAZh/23/409
- Title:
- Spectrophotometry of Mrk 509
- Short Name:
- J/PAZh/23/409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Variability of the continuum, H{beta}, H{gamma} and HeII(4686{AA}) fluxes of the Seyfert I galaxy Mrk 509 is studied using spectra obtained on the 2.6-m telescope of the Crimean Astrophysical observatory from 1971-1993. All the measurements of fluxes are in the relative units normalized to the flux of [OIII](5007{AA}) taken equal to 100. The flux in the line [OIII](5007{AA}) is estimated in the interval of (5.7-7.6)*10^-13^erg/cm^2^/s=(5.7-7.6)*10^-16^W/m2. The variability amplitude in the continuum is higher than in the hydrogen lines.
- ID:
- ivo://CDS.VizieR/J/ApJS/126/331
- Title:
- Spectrophotometry of nearby field galaxies
- Short Name:
- J/ApJS/126/331
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained integrated and nuclear spectra as well as U, B, R surface photometry for a representative sample of 196 nearby galaxies. These galaxies span the entire Hubble sequence in morphological type, as well as a wide range of luminosities (M_B_=-14 to -22). Here we present the spectrophotometry for these galaxies. The selection of the sample and the U, B, R surface photometry is described in a companion paper (J/ApJS/126/271).
- ID:
- ivo://CDS.VizieR/J/ApJS/164/81
- Title:
- Spectrophotometry of nearby galaxies
- Short Name:
- J/ApJS/164/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present integrated optical spectrophotometry for a sample of 417 nearby galaxies. Our observations consist of spatially integrated, S/N=10-100 spectroscopy between 3600 and 6900{AA} at ~8{AA} FWHM resolution. In addition, we present nuclear (2.5"x2.5") spectroscopy for 153 of these objects. Our sample targets a diverse range of galaxy types, including starbursts, peculiar galaxies, interacting/merging systems, dusty, infrared-luminous galaxies, and a significant number of normal galaxies. We use population synthesis to model and subtract the stellar continuum underlying the nebular emission lines. This technique results in emission-line measurements reliably corrected for stellar absorption. Here we present the integrated and nuclear spectra, the nebular emission-line fluxes and equivalent widths, and a comprehensive compilation of ancillary data available in the literature for our sample.
- ID:
- ivo://CDS.VizieR/J/AZh/76/604
- Title:
- Spectrophotometry of S and carbon stars
- Short Name:
- J/AZh/76/604
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The absolute energy distributions in the visual spectra (3200-7600{AA}) of 13 N carbon stars and three S stars have been investigated. The spectral resolution of the data is 50 A and the relative rms error is 2-5%. The data supplement and extend the Almaty and other spectrophotometric catalogs that are lacking in these types of objects.