- ID:
- ivo://CDS.VizieR/J/MNRAS/455/2918
- Title:
- Photometry & line luminosities for ASASSN-14li
- Short Name:
- J/MNRAS/455/2918
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ground-based and Swift photometric and spectroscopic observations of the candidate tidal disruption event (TDE) ASASSN-14li, found at the centre of PGC 043234 (d~90 Mpc) by the All-Sky Automated Survey for SuperNovae (ASAS-SN). The source had a peak bolometric luminosity of L~10^44^ erg/s and a total integrated energy of E~7x10^50^ erg radiated over the ~6 months of observations presented. The UV/optical emission of the source is well fitted by a blackbody with roughly constant temperature of T~35000 K, while the luminosity declines by roughly a factor of 16 over this time. The optical/UV luminosity decline is broadly consistent with an exponential decline, L{prop.to}e^-t/t0^, with t_0_~60 d. ASASSN-14li also exhibits soft X-ray emission comparable in luminosity to the optical and UV emission but declining at a slower rate, and the X-ray emission now dominates. Spectra of the source show broad Balmer and helium lines in emission as well as strong blue continuum emission at all epochs. We use the discoveries of ASASSN-14li and ASASSN-14ae to estimate the TDE rate implied by ASAS-SN, finding an average rate of r~4.1x10^-5^/yr per galaxy with a 90 per cent confidence interval of (2.2-17.0)x10^-5^/yr per galaxy. ASAS-SN found roughly 1 TDE for every 70 Type Ia supernovae in 2014, a rate that is much higher than that of other surveys.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/118/7
- Title:
- Photometry & morphology of UCM galaxies
- Short Name:
- J/A+AS/118/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of Thuan & Gunn r CCD imaging observations of the Universidad Complutense de Madrid (UCM) sample of emission-line galaxies (ELGs), selected by the presence of H{alpha} emission in low-resolution objective prism spectra. In this work we characterize photometrically and morphologically a total of 212 objects from the UCM survey. This Paper presents the observations and basic reductions, and lists a set of photometric parameters calculated for each UCM object. In addition, for the first time in a ELGs sample, we have determined the morphological classification of the objects using simultaneously five different criteria.
- ID:
- ivo://CDS.VizieR/J/A+A/403/93
- Title:
- Photometry of AGB stars in NGC 185 and NGC 147
- Short Name:
- J/A+A/403/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The tables represent results of an ongoing photometric survey of Local Group galaxies, using a four filter technique based on the method of Wing (1971, Proc. of the Conference on Late-Type Stars, ed. G.W. Lockwood and H.M. Dyck, KPNO Contribution 554, 145) to identify and characterise the late-type stellar content. Two narrow band filters centred on spectral features of TiO and CN allow us to distinguish between AGB stars of different chemistries [M-type (O-rich) and C-type (C-rich)]. The major parts of two dwarf galaxies, NGC 185 and NGC 147, were observed; 154 new AGB carbon stars in NGC 185 and 146 in NGC 147 were identified. All detected stars (called sample 1 in the paper) are included in the tables, with coordinates and photometric properties. All stars of sample 1 have photometry in the filters V and i. For all stars, which are in addition included in the smaller sample 2 (and have also photometry in the narrowband filters TiO and CN) the colour index (TiO-CN) is provided, too. In the tables a chemistry flag F marks in which classification group the star falls. All stars of sample 2 can have "c" for Carbon star, "o" for oxygen-rich M-type star or "r" for the rest. This correspond to the selection areas in Figure 4 of the paper. The flag for all stars of sample 1, which are not already included in sample 2 (only Vi-photometry) is "u" for unclassified.
- ID:
- ivo://CDS.VizieR/J/A+A/488/1167
- Title:
- Photometry of bulges at intermediate z
- Short Name:
- J/A+A/488/1167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Analysis of bulges to redshifts of up to z=1 have provided ambiguous results as to whether bulges as a class are old structures akin to elliptical galaxies or younger products of the evolution of their host disks. We aim to define a sample of intermediate-z disk galaxies harbouring central bulges, and a complementary sample of disk galaxies without measurable bulges. We intend to provide colour profiles for both samples, as well as measurements of nuclear, disk, and global colours, which may be used to constrain the relative ages of bulges and disks. We select a diameter-limited sample of galaxies in images from the HST/WFPC2 (Wide-Field Planetary Camera 2 at the Hubble Space Telescope) Groth Strip survey, which is divided into two subsamples of higher and lower inclination to assess the role of dust in the measured quantities. Mergers are visually identified and excluded. We take special care to control the pollution by ellipticals. The bulge sample is defined with a criterion based on nuclear surface brightness excess over the inward extrapolation of the exponential law fitted to the outer regions of the galaxies. We extract colour profiles on the semi-minor axis least affected by dust in the disk, and measure nuclear colours at 0.85kpc from the centre over those profiles. Disk colours are measured on major axis profiles; global colours are obtained from 2.6" diameter apertures. Colour transformations and K-corrections are calculated using SEDs covering bands UBVIJK, from the GOYA photometric survey. We obtain a parent sample containing 248 galaxies with known redshifts, spectroscopic or photometric, spanning 0.1<z<1.2. The bulge subsample comprises 54 galaxies (21.8% of the total), while the subsample with no measureable bulges is 55.2% of the total (137 galaxies). The remainder (23%) is composed of mergers. We list nuclear, disk, and global colours (observed and rest-frame) and magnitudes (apparent and absolute), as well as galaxy colour gradients for the samples with and without bulges, and make them available in electronic format. We also provide images, colour maps, plots of spectral energy distributions, major-axis surface brightness profiles, and minor-axis colour profiles for both samples.
- ID:
- ivo://CDS.VizieR/J/ApJS/169/225
- Title:
- Photometry of galaxies in the Coma cluster
- Short Name:
- J/ApJS/169/225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a set of UBVRIzJHKs photometry for 745 J+H-band-selected objects in a 22.5'x29.2' region centered on the core of the Coma Cluster. This includes 516 galaxies and is at least 80% complete to H=16, with a spectroscopically complete sample of 111 cluster members (nearly all with morphological classification) for H<14.5. For each object we present total Kron (1980ApJS...43..305K) magnitudes and aperture photometry. As an example, we use these data to derive color-magnitude relations for Coma early-type galaxies, measure the intrinsic scatter of these relations and its dependence on galaxy mass, and address the issue of color gradients.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A19
- Title:
- Photometry of globulars in early galaxies
- Short Name:
- J/A+A/525/A19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The combination of optical and near-infrared (NIR) colours has the potential to break the age/metallicity degeneracy and offers a better metallicity sensitivity than optical colours alone. Previous studies of extragalactic globular clusters (GCs) with this colour combination, however, have suffered from small samples or have been restricted to a few galaxies. We compile a homogeneous and representative sample of GC systems with multi-band photometry to be used in subsequent papers where ages and metallicity distributions will be studied.
- ID:
- ivo://CDS.VizieR/J/A+A/595/A43
- Title:
- Photometry of 119 HII regions in M33
- Short Name:
- J/A+A/595/A43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the dust properties of a sample of HII regions in the Local Group Galaxy M 33 presenting different spatial configurations between stars, gas, and dust. We obtain the spectral energy distribution (SED) from the UV (GALEX) to the far IR (Herschel) performing photometry in each HII region of the sample. We model the SED using DustEM tool to understand the dust evolution in different environments. The fraction of very small grains can be affected by the conditions of the interstellar environment: strong shocks existing in the interior of the most luminous HII regions can lead to fragmentation of big grains into smaller ones, while the more evolved objects provide a more quiescent environment where reformation of dust big grains might occur.
- ID:
- ivo://CDS.VizieR/J/ApJ/779/65
- Title:
- Photometry of LBGs, LAEs and GNBs at z~2.85
- Short Name:
- J/ApJ/779/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey for z~2.85 Lyman-continuum (LyC) emission in the HS1549+1933 field and place constraints on the amount of ionizing radiation escaping from star-forming galaxies. Using a custom narrowband filter (NB3420) tuned to wavelengths just below the Lyman limit at z>=2.82, we probe the LyC spectral region of 49 Lyman break galaxies (LBGs) and 91 Ly{alpha} emitters (LAEs) spectroscopically confirmed at z>=2.82. Four LBGs and seven LAEs are detected in NB3420. Using V-band data probing the rest-frame nonionizing UV, we observe that many NB3420-detected galaxies exhibit spatial offsets between their LyC and nonionizing UV emission and are characterized by extremely blue NB3420-V colors, corresponding to low ratios of nonionizing to ionizing radiation (F_UV_/F_LyC_) that are in tension with current stellar population synthesis models. We measure average values of (F_UV_/F_LyC_) for our LBG and LAE samples, correcting for foreground galaxy contamination and H I absorption in the intergalactic medium. We find (F_UV_/F_LyC_)_corr_^LBG^=82+/-45 and (F_UV_/F_LyC_)_corr_^LAE^=7.4+/-3.6. These flux density ratios correspond, respectively, to relative LyC escape fractions of f_esc,rel_^LBG^=5%-8%, and f_esc,rel_^LAE^=18%-49% absolute LyC escape fractions of f_esc,rel_^LBG^=1%-2% and f_esc,rel_^LAE^=5%-15%, and a comoving LyC emissivity from star-forming galaxies of 8.8-15.0x10^24^ erg/s/Hz/Mpc^3^. In order to study the differential properties of galaxies with and without LyC detections, we analyze narrowband Ly{alpha} imaging and rest-frame near-infrared imaging, finding that while LAEs with LyC detections have lower Ly{alpha} equivalent widths on average, there is no substantial difference in the rest-frame near-infrared colors of LBGs or LAEs with and without LyC detections. These preliminary results are consistent with an orientation-dependent model where LyC emission escapes through cleared paths in a patchy interstellar medium.
- ID:
- ivo://CDS.VizieR/J/ApJS/153/397
- Title:
- Photometry of nearby cluster galaxies
- Short Name:
- J/ApJS/153/397
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric observations are presented for 8747 galaxies in the fields of 28 clusters with redshifts in the range 0.05<z<0.11 and spanning a wide range in Abell richness class. The primary motivation for this study is to provide a nearby sample of clusters whose galaxy populations can be used to provide an anchor point for evolutionary studies of cluster galaxy populations.
- ID:
- ivo://CDS.VizieR/J/A+A/410/795
- Title:
- Photometry of NGC 3109 carbon stars
- Short Name:
- J/A+A/410/795
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a CFH12K wide field survey of the carbon star population in and around NGC 3109. Carbon stars, the brightest members of the intermediate-age population, were found nearly exclusively in and near the disk of NGC 3109, ruling out the existence of an extensive intermediate-age halo like the one found in NGC 6822. Over 400 carbon stars identified have M_I_=-4.71, confirming the nearly universality of mean magnitude of C star populations in Local Group galaxies. Star counts over the field reveal that NGC 3109 is a truncated disk shaped galaxy without an extensive stellar halo. The minor axis star counts reach the foreground density between 4' and 5', a distance that can be explained by an inclined disk rather than a spheroidal halo. We calculate a global C/M ratio of 1.75+/-0.20, a value expected for such a metal poor galaxy.
