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6322. First month on SN 2013ej
- ID:
- ivo://CDS.VizieR/J/MNRAS/438/L101
- Title:
- First month on SN 2013ej
- Short Name:
- J/MNRAS/438/L101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present early photometric and spectroscopic observations of SN 2013ej, a bright Type IIP supernova (SN) in M74. SN 2013ej is one of the closest SNe ever discovered. The available archive images and the early discovery help to constrain the nature of its progenitor. The earliest detection of this explosion was on 2013 July 24.125 ut and our spectroscopic monitoring with the FLOYDS spectrographs began on July 27.7 ut, continuing almost daily for two weeks. Daily optical photometric monitoring was achieved with the 1m telescopes of the Las Cumbres Observatory Global Telescope (LCOGT) network, and was complemented by UV data from Swift and near-infrared spectra from Public ESO Spectroscopic Survey of Transient Objects and Infrared Telescope Facility. The data from our monitoring campaign show that SN 2013ej experienced a 10d rise before entering into a well-defined plateau phase. This unusually long rise time for a Type IIP has been seen previously in SN 2006bp and SN 2009bw. A relatively rare strong absorption blueward of H{alpha} is present since our earliest spectrum. We identify this feature as SiII, rather than high-velocity H{alpha} as sometimes reported in the literature.
- ID:
- ivo://CDS.VizieR/J/ApJ/699/L43
- Title:
- FIRST-NVSS-SDSS AGN sample catalog
- Short Name:
- J/ApJ/699/L43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radio outflows of active galactic nuclei (AGNs) are invoked in cosmological models as a key feedback mechanism in the latest phases of massive galaxy formation. Recently, it has been suggested that the two major radio AGN populations-the powerful high-excitation, and the weak low-excitation radio AGNs (HERAGN and LERAGN, respectively)-represent two earlier and later stages of massive galaxy buildup. To test this, here we make use of a local (0.04<z<0.1) sample of ~500 radio AGNs with available optical spectroscopy, drawn from the FIRST, NVSS, SDSS, and 3CRR surveys.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1977
- Title:
- FIRST-Optical-VLA survey for lensed radio lobes
- Short Name:
- J/AJ/130/1977
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey for gravitationally lensed radio lobes. Lensed lobes are a potentially richer source of information about galaxy mass distributions than lensed point sources, which have been the exclusive focus of other recent surveys. Our approach is to identify radio lobes in the Faint Images of the Radio Sky at Twenty cm (FIRST, Cat. <VIII/71>) catalog and then search optical catalogs for coincident foreground galaxies, which are candidate lensing galaxies. We then obtain higher resolution images of these targets at both optical and radio wavelengths and obtain optical spectra for the most promising candidates. We present maps of several radio lobes that are nearly coincident with galaxies. We have not found any new and unambiguous cases of gravitational lensing. One radio lobe in particular, FOV J0743+1553, has two hot spots that could be multiple images produced by a z=0.19 spiral galaxy, but the lensing interpretation is problematic.
- ID:
- ivo://CDS.VizieR/J/A+A/454/257
- Title:
- First overtone RR Lyrae in LMC
- Short Name:
- J/A+A/454/257
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using the full span of multicolor data on a representative sample of first overtone RR Lyrae stars in the Large Magellanic Cloud (LMC), we revisit the problem of the incidence rate of the amplitude/phase-modulated (Blazhko) stars. Methods. Multicolor data, obtained by the MAssive Compact Halo Objects (MACHO) project, are utilized through a periodogram averaging method. Multicolor data, obtained by the MAssive Compact Halo Objects (MACHO) project, are utilized through a periodogram averaging method.
- ID:
- ivo://CDS.VizieR/J/ApJ/764/102
- Title:
- First quadrant IRDCs in CS(2-1) with Mopra
- Short Name:
- J/ApJ/764/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared dark clouds (IRDCs) are believed to host the earliest stages of high-mass star and cluster formation. Because O stars typically travel short distances over their lifetimes, if IRDCs host the earliest stages of high-mass star formation then these cold, dense molecular clouds should be located in or near the spiral arms in the Galaxy. The Galactic distribution of a large sample of IRDCs should therefore provide information on Galactic structure. Moreover, determination of distances enables mass and luminosity calculations. We have observed a large sample of IRDC candidates in the first Galactic quadrant in the dense gas tracer CS(2-1) using the Mopra telescope in order to determine kinematic distances from the molecular line velocities. We find that the IRDCs are concentrated around a Galactocentric distance of ~4.5kpc, agreeing with the results of Simon et al. (2006, J/ApJ/653/1325). This distribution is consistent with the location of the Scutum-Centaurus spiral arm. The group of IRDCs near the Sun in the first quadrant detected in ^13^CO(1-0) in Simon et al. is not detected in the CS data. This discrepancy arises from the differences in the critical densities between the ^13^CO(1-0) and CS(2-1) lines. We determine that the Midcourse Space Experiment selected IRDCs are not a homogeneous population, and ^13^CO(1-0) traces a population of IRDCs with lower column densities and lower 1.1 mm flux densities in addition to more dense IRDCs detected in CS. Masses of the first quadrant IRDCs are calculated from ^13^CO(1-0) maps. We find a strong peak in the Galactocentric IRDC mass surface density distribution at R_Gal_~4.5kpc.
- ID:
- ivo://CDS.VizieR/J/AJ/121/1872
- Title:
- FIRST radio-selected QSOs
- Short Name:
- J/AJ/121/1872
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained single-epoch optical photometry for 202 quasars, taken from the FIRST Bright Quasar Survey (FBQS), which span a wide range in radio loudness. Comparison with the magnitudes of these objects on the POSS-I plates provides by far the largest sample of long-term variability amplitudes for radio-selected quasars yet produced. We find the quasars to be more variable in the blue than in the red band, consistent with work on optically selected samples. The previously noted trend of decreasing variability with increasing optical luminosity applies only to radio-quiet objects. Furthermore, we do not confirm a rise in variability amplitude with redshift, nor do we see any dependence on radio flux or luminosity. The variability over a radio-optical flux ratio range spanning a factor of 60000 from radio-quiet to extreme radio-loud objects is largely constant, although there is a suggestion of greater variability in the extreme radio-loud objects. We demonstrate the importance of Malmquist bias in variability studies and develop a procedure to correct for the bias in order to reveal the underlying variability properties of the sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/883/175
- Title:
- First release of the MaNGA Stellar Library (MaStar)
- Short Name:
- J/ApJ/883/175
- Date:
- 29 Nov 2021 07:46:33
- Publisher:
- CDS
- Description:
- We present the first release of the MaNGA Stellar Library (MaStar), which is a large, well-calibrated, high-quality empirical library covering the wavelength range 3622-10354{AA} at a resolving power of R~1800. The spectra were obtained using the same instrument as used by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, by piggybacking on the Sloan Digital Sky Survey (SDSS-IV)/Apache Point Observatory Galaxy Evolution Experiment 2-N (APOGEE-2N) observations. Compared to previous empirical libraries, the MaStar library will have a higher number of stars and a more comprehensive stellar-parameter coverage, especially of cool dwarfs, low-metallicity stars, and stars with different [{alpha}/Fe], achieved by a sophisticated target-selection strategy that takes advantage of stellar-parameter catalogs from the literature. This empirical library will provide a new basis for stellar-population synthesis and is particularly well suited for stellar-population analysis of MaNGA galaxies. The first version of the library contains 8646 high-quality per-visit spectra for 3321 unique stars. Compared to photometry, the relative flux calibration of the library is accurate to 3.9% in g-r, 2.7% in r-i, and 2.2% in i-z. The data are released as part of SDSS Data Release 15. We expect the final release of the library to contain more than 10000 stars.
- ID:
- ivo://CDS.VizieR/J/ApJS/196/12
- Title:
- First results from Mopra HCO^+^ maps
- Short Name:
- J/ApJS/196/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Census of High- and Medium-mass Protostars (CHaMP) is the first large-scale, unbiased, uniform mapping survey at sub-parsec-scale resolution of 90GHz line emission from massive molecular clumps in the Milky Way. We present the first Mopra (ATNF) maps of the CHaMP survey region (300{deg}>l>280{deg}) in the HCO^+^J=1->0 line, which is usually thought to trace gas at densities up to 10^11^m^-3^. In this paper, we introduce the survey and its strategy, describe the observational and data reduction procedures, and give a complete catalog of moment maps of the HCO^+^J=1->0 emission from the ensemble of 303 massive molecular clumps. From these maps we also derive the physical parameters of the clumps, using standard molecular spectral-line analysis techniques.
- ID:
- ivo://CDS.VizieR/J/AJ/159/187
- Title:
- First RVs with the EXPRES spectrograph: 51Peg
- Short Name:
- J/AJ/159/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The EXtreme-PREcision Spectrograph (EXPRES) is an environmentally stabilized, fiber-fed, R=137500, optical spectrograph. It was recently commissioned at the 4.3m Lowell Discovery Telescope near Flagstaff, Arizona. The spectrograph was designed with a target radial-velocity (RV) precision of 30cm/s. In addition to instrumental innovations, the EXPRES pipeline, presented here, is the first on-sky, optical, fiber-fed spectrograph to employ many novel techniques-including an "extended flat" fiber used for wavelength-dependent quantum efficiency characterization of the CCD, a flat-relative optimal extraction algorithm, chromatic barycentric corrections, chromatic calibration offsets, and an ultra-precise laser frequency comb for wavelength calibration. We describe the reduction, calibration, and RV analysis pipeline used for EXPRES and present an example of our current sub-meter-per-second RV measurement precision, which reaches a formal, single-measurement error of 0.3m/s for an observation with a per-pixel signal-to-noise ratio of 250. These velocities yield an orbital solution on the known exoplanet host 51Peg that matches literature values with a residual rms of 0.895m/s.