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2431. Spectral properties of Type Ic & Ic-bl SNe
ID:
ivo://CDS.VizieR/J/ApJ/832/108
Title:
Spectral properties of Type Ic & Ic-bl SNe
Short Name:
J/ApJ/832/108
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first systematic investigation of spectral properties of 17 Type Ic Supernovae (SNe Ic), 10 broad-lined SNe Ic (SNe Ic-bl) without observed gamma-ray bursts (GRBs), and 11 SNe Ic-bl with GRBs (SN-GRBs) as a function of time in order to probe their explosion conditions and progenitors. Using a number of novel methods, we analyze a total of 407 spectra, which were drawn from published spectra of individual SNe as well as from the densely time-sampled spectra of Modjaz+ (2014, J/AJ/147/99). In order to quantify the diversity of the SN spectra as a function of SN subtype, we construct average spectra of SNe Ic, SNe Ic-bl without GRBs, and SNe Ic-bl with GRBs. We find that SN 1994I is not a typical SN Ic, contrasting the general view, while the spectra of SN 1998bw/GRB 980425 are representative of mean spectra of SNe Ic-bl. We measure the ejecta absorption and width velocities using a new method described here and find that SNe Ic-bl with GRBs, on average, have quantifiably higher absorption velocities, as well as broader line widths than SNe without observed GRBs. In addition, we search for correlations between SN-GRB spectral properties and the energies of their accompanying GRBs. Finally, we show that the absence of clear He lines in optical spectra of SNe Ic-bl, and in particular of SN-GRBs, is not due to them being too smeared-out due to the high velocities present in the ejecta. This implies that the progenitor stars of SN-GRBs are probably free of the He-layer, in addition to being H-free, which puts strong constraints on the stellar evolutionary paths needed to produce such SN-GRB progenitors at the observed low metallicities.
2432. Spectral study of 19 radio sources
ID:
ivo://CDS.VizieR/J/AZh/82/420
Title:
Spectral study of 19 radio sources
Short Name:
J/AZh/82/420
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical identifications, classifications, and radio spectra of 19 radio sources from a complete sample in flux-density with the declinations 10{deg}-12{deg}30' (J2000) obtained with the 6-m optical telescope (4000-9000{AA}) and RATAN-600 radio telescope (0.97-21.7GHz) of the Special Astrophysical Observatory. Twelve objects with redshifts from 0.573-2.694 have been classified as quasars, and two objects with featureless spectra as BL Lac objects. Four objects are emission-line radio galaxies with redshifts from 0.204 to 0.311, one object is an absorption-line radio galaxy with redshift 0.214. Radio flux densities have been obtained at six frequencies for all sources except for two extended objects. The radio spectra of five of the sources can be separated into extended and compact components. Three objects display substantial rapid and long-term variability of their flux densities.
2433. Spectral survey of Case emission-line galaxies
ID:
ivo://CDS.VizieR/J/A+AS/131/295
Title:
Spectral survey of Case emission-line galaxies
Short Name:
J/A+AS/131/295
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of the follow-up spectroscopy of 178 emission-line galaxy (ELG) candidates from the Case objective-prism survey and nine Markarian galaxies with the 6m telescope are described. Only the candidates classified in the Case survey as those with emission lines were observed with the aim to form a statistical sample of blue compact galaxies (BCGs) with strong emission lines in the zone RA: 8h-16h, and DE: =+29deg-+38deg. We present the redshifts, equivalent widths and flux ratios for the strongest lines and the spectrum type for most of the galaxies with detected emission lines. A significant fraction (about 23%) of the observed Case galaxies do not show emission lines in blue. Preliminary analysis of the data is presented and the properties of the observed ELGs are compared with those of other known samples.
2434. Spectral templates for galaxies from 0.2 to 10um
ID:
ivo://CDS.VizieR/J/ApJ/676/286
Title:
Spectral templates for galaxies from 0.2 to 10um
Short Name:
J/ApJ/676/286
Date:
21 Oct 2021
Publisher:
CDS
Description:
We built an optimal basis of low-resolution templates for galaxies over the wavelength range from 0.2 to 10um using a variant of the algorithm presented by Budavari and coworkers. We derived them using 11 bands of photometry from the NDWFS, FLAMEX, zBootes, and IRAC Shallow surveys for 16033 galaxies in the NDWFS Bootes field with spectroscopic redshifts measured by the AGN and Galaxy Evolution Survey. We also developed algorithms to accurately determine photometric redshifts, K-corrections, and bolometric luminosities using these templates. Our photometric redshifts have an accuracy of sigma_z_/(1+z)=0.04 when clipped to the best 95%. We used these templates to study the spectral type distribution in the field and to estimate luminosity functions of galaxies as a function of redshift and spectral type. In particular, we note that the 5-8um color distribution of galaxies is bimodal, much like the optical g-r colors.
2435. Spectra of Abell 2384 galaxies
ID:
ivo://CDS.VizieR/J/A+A/570/A40
Title:
Spectra of Abell 2384 galaxies
Short Name:
J/A+A/570/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectrophotometric analysis of the galaxy population in the area of the merging cluster Abell 2384 at z=0.094. We investigate the impact of the complex cluster environment on galaxy properties, such as colour, morphology, and star formation rate. We combined multi-object spectroscopy from the 2dF and EFOSC2 spectrographs with optical imaging of the inner 30x30-arcmin of A2384 taken with the ESO Wide Field Imager. We carried out a kinematical analysis using the EMMIX algorithm and biweight statistics. We address the possible presence of cluster substructures with the Dressler-Shectman test. Cluster galaxies are investigated with respect to [OII] and H{alpha} equivalent width. Galaxies covered by our optical imaging observations are additionally analysed in terms of colour, star formation rate, and morphological descriptors, such as Gini coefficient and M20 index. We study cluster galaxy properties as a function of clustercentric distance and investigate the distribution of various galaxy types in colour-magnitude and physical space.
2436. Spectra of a Holmium in the near-UV. I. Ho I.
ID:
ivo://CDS.VizieR/J/ApJS/228/16
Title:
Spectra of a Holmium in the near-UV. I. Ho I.
Short Name:
J/ApJS/228/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Fourier Transform spectra of a Holmium hollow cathode discharge lamp have been investigated in the UV spectral range from 25000 up to 31530cm^-1^ (317 to 400nm). Two Ho spectra have been measured with neon and argon as buffer gases. Based on the intensity ratios from these two spectra, a distinction was made between atomic and ionic lines (ionic lines are discussed in an accompanying paper). Using the known Ho I energy levels, 71 lines could be classified as transitions of atomic Ho, 34 of which have not been published previously. Another 32 lines, which could not be classified, are listed in the literature and assigned as atomic Ho. An additional 370 spectral lines have been assigned to atomic Ho based on the signal-to-noise ratio in the two spectra measured under different discharge conditions, namely with buffer gases argon and neon, respectively. These 370 lines have not been previously listed in the literature.
2437. Spectra of a Holmium in the near-UV. II.
ID:
ivo://CDS.VizieR/J/ApJS/228/17
Title:
Spectra of a Holmium in the near-UV. II.
Short Name:
J/ApJS/228/17
Date:
21 Oct 2021
Publisher:
CDS
Description:
Fourier Transform spectra of Holmium (Ho) in the UV spectral range from 31530 to 25000cm^-1^ (317 to 400nm) have been investigated, particularly focusing on the ionic lines. The distinction between the different degrees of ionization (I, II, and III) is based on differences in signal-to-noise ratios from two Ho spectra, which have been measured with different buffer gases, i.e., neon and argon. Based on 106 known Ho II and 126 known Ho III energy levels, 97 lines could be classified as transitions of singly ionized Ho and 9 lines could be classified as transitions of doubly ionized Ho. Of the 97 Ho II lines, 6 have not been listed in the extant literature. Another 215 lines have been assigned to Ho II, though they could not be classified on the basis of the known energy levels.
2438. Spectra of a rare low-mass Wolf-Rayet star in LMC
ID:
ivo://CDS.VizieR/J/ApJ/888/54
Title:
Spectra of a rare low-mass Wolf-Rayet star in LMC
Short Name:
J/ApJ/888/54
Date:
25 Oct 2021 10:12:43
Publisher:
CDS
Description:
We report the serendipitous discovery of an object, UVQSJ060819.93-715737.4, with a spectrum dominated by extremely intense, narrow CII emission lines. The spectrum is similar to those of the very rare, late-type [WC11] low-mass Wolf-Rayet stars. Despite the recognition of these stars as a distinct class decades ago, there remains barely a handful of Galactic members, all of which are also planetary-nebula central stars. Although no obvious surrounding nebulosity is present in J0608, [OII], [NII], and [SII] emission suggest the presence of an inconspicuous, low-excitation nebula. There is low-amplitude incoherent photometric variability on timescales of days to years, as well as numerous prominent P Cygni profiles, implying mass loss. There are indications of a binary companion. The star is located on the outskirts of the LMC, and the observed radial velocity (~+250km/s) and proper motion strongly suggest membership. If indeed an LMC member, this is the first extragalactic late [WC] star, and the first with an accurately determined luminosity, as the Galactic examples are too distant for precise parallax determinations. A high-quality, broad-coverage spectrum of the prototype of the late [WC] class, CPD -56 8032, is also presented. We discuss different excitation mechanisms capable of producing the great strength of the CII emission. Numerous autoionizing levels of C II are definitely populated by processes other than dielectronic recombination. Despite the spectacular emission spectra, observational selection makes objects such as these difficult to discover. Members of the [WC11] class may in fact be considerably more common than the handful of previously known late [WC] stars.
2439. Spectra of 73 asteroids
ID:
ivo://CDS.VizieR/J/A+A/630/A141
Title:
Spectra of 73 asteroids
Short Name:
J/A+A/630/A141
Date:
21 Oct 2021
Publisher:
CDS
Description:
Several primitive families in the inner region of the main asteroid belt were identified as potential sources for two near-Earth asteroids (NEAs), (101955) Bennu and (162173) Ryugu, targets of the sample-return missions OSIRIS-REx and Hayabusa2, respectively. Four of the families, located at high proper inclinations (i>10{deg}), have not yet been compositionally studied: Klio, Chaldaea, Chimaera, and Svea. We want to characterize and analyze these families within the context of our PRIMitive Asteroid Spectroscopic Survey (PRIMASS), in order to complete the puzzle of the origins of the two NEAs. We obtained visible spectra (0.5-0.9um) of a total of 73 asteroids within the Klio, Chaldaea, Chimaera, and Svea collisional families, using the instrument OSIRIS at the 10.4m Gran Telescopio Canarias. We performed a taxonomical classification of these objects, and an analysis of the possible presence of absorption bands related to aqueous alterations, comparing the results with already studied primitive families in the inner main belt. We present here reflectance spectra for 30 asteroids in the Klio family, 15 in Chaldaea, 20 in Chimaera, and 8 in Svea. We show that Klio, Chaldaea, and Chimaera members have moderately red spectral slopes, with aqueous alteration absorption bands centered around 0.7um, characteristic of the group of primitive families known as Erigone-like. In contrast, Svea shows no 0.7um features, and neutral and blue spectral slopes, and thus is a Polana-like family. While all four families might be related to (162173) Ryugu, the only family studied in this work that might be related to (101955) Bennu is Svea.
2440. Spectra of blue compact galaxies
ID:
ivo://CDS.VizieR/J/A+A/396/503
Title:
Spectra of blue compact galaxies
Short Name:
J/A+A/396/503
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the second paper in a series studying the star formation rates, stellar components, metallicities, and star formation histories and evolution of a sample of blue compact galaxies. We analyzed spectral properties of 97 blue compact galaxies, obtained with the Beijing Astronomical Observatory (China) 2.16m telescope, with spectral range 3580{AA}-7400{AA}. We classify the spectra according to their emission lines: 13 of the total 97 BCG sample are non-emission line galaxies (non-ELGs); 10 have AGN-like emission (AGNs), and 74 of them are star-forming galaxies (SFGs). Emission line fluxes and equivalent widths, continuum fluxes, the 4000A Balmer break index and equivalent widths of absorption lines are measured from the spectra. Please find more detail information in http://optik2.mtk.nao.ac.jp/~xkong/bcg/

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