- ID:
- ivo://CDS.VizieR/J/A+A/629/A57
- Title:
- Supernova ASASSN-14jb light curves and spectra
- Short Name:
- J/A+A/629/A57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical photometry and spectroscopy of the Type II supernova ASASSN-14jb, together with very large telescope (VLT) multi unit spectroscopic explorer (MUSE) integral field observations of its host galaxy and a nebular-phase spectrum. This supernova, in the nearby galaxy ESO 467-G051 (z=0.006), was discovered and followed-up by the all-sky automated survey for supernovae (ASAS-SN). We obtained well-sampled las cumbres network (LCOGTN) BVgri and Swift w2m1w1ubv optical, near-UV/optical light curves, and several optical spectra in the early photospheric phases. The transient ASASSN-14jb exploded ~2kpc above the star-forming disk of ESO 467-G051, an edge-on disk galaxy. The large projected distance from the disk of the supernova position and the non-detection of any HII region in a 1.4kpc radius in projection are in conflict with the standard environment of core-collapse supernova progenitors and suggests the possible scenario that the progenitor received a kick in a binary interaction. We present analysis of the optical light curves and spectra, from which we derived a distance of 25+/-2Mpc using state-of-the-art empirical methods for Type II SNe, physical properties of the SN explosion (^56^Ni mass, explosion energy, and ejected mass), and properties of the progenitor; namely the progenitor radius, mass, and metallicity. Our analysis yields a ^56^Ni mass of 0.0210+/-0.0025M_{sun}_, an explosion energy of ~0.25x10^51^ergs, and an ejected mass of ~6M_{sun}_. We also constrained the progenitor radius to be R*=580+/-28R_{sun}_ which seems to be consistent with the sub-Solar metallicity of 0.3+/-0.1Z_{sun}_ derived from the supernova FeII {lambda} 5018 line. The nebular spectrum constrains strongly the progenitor mass to be in the range 10-12M_{sun}_. From the Spitzer data archive we detect ASASSN-14jb ~330-days past explosion and we derived a total dust mass of 10^-4^M_{sun}_ from the 3.6um and 4.5um photometry. Using the FUV, NUV, BVgri,Ks, 3.6um, and 4.5u total magnitudes for the host galaxy, we fit stellar population synthesis models, which give an estimate of M*~1x10^9^M_{sun}_ , an age of 3.2Gyr, and a SFR~0.07M_{sun}_/yr. We also discuss the low oxygen abundance of the host galaxy derived from the MUSE data, having an average of 12+log(O/H)=8.27^+0.16^_-0.20_ using the O3N2 diagnostic with strong line methods. We compared it with the supernova spectra, which is also consistent with a sub-Solar metallicity progenitor. Following recent observations of extraplanar H II regions in nearby edge-on galaxies, we derived the metallicity offset from the disk, being positive, but consistent with zero at 2{sigma}, suggesting enrichment from disk outflows. We finally discuss the possible scenarios for the unusual environment for ASASSN-14jb and conclude that either the in-situ star formation or runaway scenario would imply a low-mass progenitor, agreeing with our estimate from the supernova nebular spectrum. Regardless of the true origin of ASASSN-14jb, we show that the detailed study of the environment roughly agree with the stronger constraints from the observation of the transient.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/657/A64
- Title:
- Supernovae ZTF light curves
- Short Name:
- J/A+A/657/A64
- Date:
- 16 Mar 2022 13:01:07
- Publisher:
- CDS
- Description:
- Stripped-envelope supernovae (SE SNe) of Type Ib and Type Ic are thought to result from explosions of massive stars having lost their outer envelopes. The favoured explosion mechanism is by core-collapse, with the shock later revived by neutrino heating. However, there is an upper limit to the amount of radioactive ^56^Ni that such models can accomplish. Recent literature point to a tension between the maximum luminosity from such simulations and observations. We use a well characterized sample of SE SNe from the Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS). We scrutinize the observational caveats regarding estimating the maximum luminosity (and thus the amount of ejected radioactive nickel) for the members of this sample. We employ the strict selection criteria for the BTS to collect a sample of spectroscopically classified normal Type Ibc SNe for which we use the ZTF light curves to determine the maximum luminosity. We cull the sample further based on data quality, light-curve shape, distance and colors, and examine uncertainties that may affect the numbers. The methodology of the sample construction from this BTS sample can be used for many other future investigations. We analyze observational data, consisting of optical light curves and spectra, for the selected sub-samples. In total we use 129 Type Ib or Type Ic BTS SNe with an initial rough luminosity distribution peaked at M_r_=-17.61+/-0.72, and where 36% are apparently brighter than the theoretically predicted maximum brightness of M_r_=-17.8. When we further cull this sample to ensure that the SNe are normal Type Ibc with good LC data within the Hubble flow, the sample of 94 objects has M_r_=-17.64+/-0.54. A main uncertainty in absolute magnitude determinations for SNe is the host galaxy extinction correction, but the reddened objects only get more luminous after corrections. If we simply exclude objects with red, unusual or uncertain colors, we are left with 14 objects at M_r_=-17.90+/-0.73, whereof a handful are most certainly brighter than the suggested theoretical limit. The main result of this study is thus that normal SNe Ibc do indeed reach luminosities above 10^42.6^erg/s, apparently in conflict with existing explosion models.
2743. Supernova LSQ13fn
- ID:
- ivo://CDS.VizieR/J/A+A/588/A1
- Title:
- Supernova LSQ13fn
- Short Name:
- J/A+A/588/A1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical imaging and spectroscopy of supernova (SN) LSQ13fn, a type II supernova with several hitherto-unseen properties. Although it initially showed strong symmetric spectral emission features attributable to HeII, NIII, and CIII, reminiscent of some interacting SNe, it transitioned into an object that would fall more naturally under a type II-Plateau (IIP) classification. However, its spectral evolution revealed several unusual properties: metal lines appeared later than expected, were weak, and some species were conspicuous by their absence. Furthermore, the line velocities were found to be lower than expected given the plateau brightness, breaking the SN IIP standardised candle method for distance estimates. We found that, in combination with a short phase of early-time ejecta-circumstellar material interaction, metal-poor ejecta, and a large progenitor radius could reasonably account for the observed behaviour. Comparisons with synthetic model spectra of SNe IIP of a given progenitor mass would imply a progenitor star metallicity as low as 0.1Z_{sun}_. LSQ13fn highlights the diversity of SNe II and the many competing physical effects that come into play towards the final stages of massive star evolution immediately preceding core-collapse.
- ID:
- ivo://CDS.VizieR/II/135
- Title:
- Suppl. to Diffuse Interstellar Band Measurements
- Short Name:
- II/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This bibliographic search has been undertaken in order to gather all data concerning four diffuse interstellar bands (DIB) published since the Snow, York, and Welty (1977) catalogue, and up to 1987.0. These four DIB are : 4430, 5780, 5797, and 6284 Angstrom. In the present set of data, no statistical reduction to a unique system has been made because most of the lists contain only few data.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/725
- Title:
- Survey of diffuse interstellar bands
- Short Name:
- J/MNRAS/423/725
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents an atlas of diffuse interstellar bands together with tables with measurements of their parameters: central wavelengths, full widths at half-maximum and equivalent widths. For this goal the spectra of ten reddened, early-type stars have been selected. The spectra are of high resolution, ~100000, and reasonable signal-to-noise ratio, S/N>300; they cover a wide spectral range 3500-10000{AA} and show a lack of evident Doppler splitting in the interstellar KI line. The measurement technique has allowed a homogeneous set of data to be achieved. As a result, the identity of 336 DIBs from previous surveys has been confirmed and 21 new bands have been found.
- ID:
- ivo://CDS.VizieR/J/MNRAS/253/686
- Title:
- Survey of faint compact objects
- Short Name:
- J/MNRAS/253/686
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a low-resolution (73A) spectroscopic survey of faint compact objects conducted with the Low Dispersion Survey Spectrograph at the Anglo-Australian Telescope. The sample is a random subset of all compact sources with 22.5<=b_j_<=23.5 in three high-latitude fields. Additional data on compact sources with 21<=b_j_<=22.5 have been selected from the higher resolution (13A) survey previously published by Colless et al. (1990), and a subset of these brighter objects has been studied at both dispersions.
- ID:
- ivo://CDS.VizieR/J/ApJS/177/39
- Title:
- Survey of low-redshift OVI absorbers
- Short Name:
- J/ApJS/177/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using high-resolution ultraviolet spectra of 16 low-z QSOs obtained with the E140M echelle mode of the Space Telescope Imaging Spectrograph, we study the physical conditions and statistics of OVI absorption in the intergalactic medium (IGM) at z<0.5. We identify 51 intervening (z_abs_<z_QSO_) OVI systems comprising 77 individual components, and we find 14 "proximate" systems (z_abs_~z_QSO_) containing 34 components. For intervening systems (components) with rest-frame equivalent width W_r_>30m{AA}, the number of OVI absorbers per unit redshift dN/dz=15.6^+2.9^_-2.4_(21.0^+3.2^_-2.8_), and this decreases to dN/dz=0.9^+1.0^_-0.5_(0.3^+0.7^_-0.3_) for W_r_>300m{AA}. The number per redshift increases steeply as z_abs_ approaches z_QSO_; we find that dN/dz is ~3-10 times higher within 2500km/s of z_QSO_. The most striking difference between intervening and proximate systems is that some proximate absorbers have substantially lower HI/OVI ratios.
2748. Survey of novae in M31
- ID:
- ivo://CDS.VizieR/J/ApJ/734/12
- Title:
- Survey of novae in M31
- Short Name:
- J/ApJ/734/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a multi-year spectroscopic and photometric survey of novae in M31 that resulted in a total of 53 spectra of 48 individual nova candidates. Two of these, M31N 1995-11e and M31N 2007-11g, were revealed to be long-period Mira variables, not novae. These data double the number of spectra extant for novae in M31 through the end of 2009 and bring to 91 the number of M31 novae with known spectroscopic classifications. We find that 75 novae (82%) are confirmed or likely members of the FeII spectroscopic class, with the remaining 16 novae (18%) belonging to the He/N (and related) classes. These numbers are consistent with those found for Galactic novae. We find no compelling evidence that spectroscopic class depends sensitively on spatial position or population within M31 (i.e., bulge versus disk), although the distribution for He/N systems appears slightly more extended than that for the FeII class. We confirm the existence of a correlation between speed class and ejection velocity (based on line width), as in the case of Galactic novae. Follow-up photometry allowed us to determine light-curve parameters for a total of 47 of the 91 novae with known spectroscopic class. We confirm that more luminous novae generally fade the fastest and that He/N novae are typically faster and brighter than their FeII counterparts. In addition, we find a weak dependence of nova speed class on position in M31, with the spatial distribution of the fastest novae being slightly more extended than that of slower novae.
- ID:
- ivo://CDS.VizieR/J/A+A/645/A18
- Title:
- SVOM-ECLAIRs known X-ray sources catalogue
- Short Name:
- J/A+A/645/A18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SVOM mission currently under development will carry various instruments, and in particular the coded-mask telescope ECLAIRs, with a large field of view of about 2sr, operating in the 4-150keV energy band. The main goal of ECLAIRs is to detect high-energy transients such as gamma-ray bursts. Its onboard trigger software will search for new hard X-ray sources appearing in the sky, as well as peculiar behaviour (e.g. strong outbursts) from known sources, in order to repoint the satellite to perform follow-up observations with its onboard narrow-field-of-view instruments. The presence of known X-ray sources must be disentangled from the appearance of new sources. This is done with the help of an onboard source catalogue, which we present in this paper. As an input we use catalogues of X-ray sources detected by Swift/BAT and MAXI/GSC and we study the influence of the sources on ECLAIRs' background level and on the quality of the sky-image reconstruction process. We show that the influence of the sources depends on the pointing direction on the sky, on the energy band, and on the exposure time. In the Galactic centre, the contribution from known sources largely dominates the cosmic X-ray background, which is, on the contrary, the main background in sky regions lacking strong sources. We also demonstrate the need to clean the contributions of these sources in order to maintain a low noise level in the sky images and to maintain a low threshold for the detection of new sources without introducing false triggers. We briefly describe one of our cleaning methods and its challenges. Finally, we present the overall structure of the onboard catalogue and the way it will be used to perform the source cleaning and disentangle detections of new sources from outbursts of known sources.
2750. Swan system of C2
- ID:
- ivo://CDS.VizieR/J/ApJS/169/472
- Title:
- Swan system of C2
- Short Name:
- J/ApJS/169/472
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The C2 Swan system (d ^3^{Pi}_g_-a ^3^{Pi}_u_) was observed in emission for the {Delta}v=-3 to {Delta}v=+2 sequences in the 14000-24000cm^-1^ spectral range using a Fourier transform spectrometer. We carried out a global simultaneous fit by including a wide range of vibrational states. A total of 34 bands with v'=0-10 and v"=0-9 were rotationally assigned. Numerous discrepancies were found in the assignments and in the measured transition wavenumbers between the new measurements and previous results. Most of the measured transition wavenumbers and their assignments for relatively low-v bands agreed with published data. On the contrary, for high-v bands our line positions and assignments disagreed with the tabulated literature values. In particular, the lines of six bands involving the levels with v'=4, 5, and 6 are almost completely different from the previous work. Major sources of the disagreement are thought to be line congestion and perturbations found in these bands. From the analysis, perturbations for v'=0, 1, 2, 4, 6, 8, 9, and 10 in the d ^3^{Pi}_g_ state were identified. A study of these rotational perturbations suggest that some of them are likely caused by interactions with high-v levels of the b ^3^{Sigma}^-^_g_ state.
