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- ID:
- ivo://CDS.VizieR/J/A+A/552/A124
- Title:
- SNLS and SDSS SN surveys photometric calibration
- Short Name:
- J/A+A/552/A124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a joined photometric calibration for the SNLS and the SDSS supernova surveys. Our main delivery are catalogs of natural AB magnitudes for a large set of selected tertiary standard stars covering the science field of both surveys. Those catalogs are calibrated to the AB flux scale through observations of 5 primary spectrophotometric standard stars, for which HST-STIS spectra are available in the CALSPEC database. The estimate of the uncertainties associated to this calibration are delivered as a single covariance matrix. We also provide a model of the transmission efficiency of the SNLS photometric instrument MegaCam. Those transmission functions are required for the interpretation of MegaCam natural magnitudes in term of physical fluxes. Similar curves for the SDSS photometric instrument have been published in Doi et al. (2010AJ....139.1628D). Last, we release the measured magnitudes of the five CALSPEC standard stars in the magnitude system of the tertiary catalogs. This makes it possible to update the calibration of the tertiary catalogs if CALSPEC spectra for the primary standards are revised.
- ID:
- ivo://CDS.VizieR/J/A+A/655/A105
- Title:
- 3 SN multiwavelength light curves
- Short Name:
- J/A+A/655/A105
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present the discovery and extensive follow-up observations of SN 2020jfo, a Type IIP supernova (SN) in the nearby (14.5Mpc) galaxy M61. Optical light curves (LCs) and spectra from the Zwicky Transient Facility (ZTF), complemented with data from Swift/UVOT and near-infrared photometry is presented. These are used to model the 350-day duration bolometric light curve, which exhibits a relatively short (~65 days) plateau. This implies a moderate ejecta mass (~5M_{sun}_) at the time of explosion, whereas the deduced amount of ejected radioactive nickel is ~0.025M_{sun}_. An extensive series of spectroscopy is presented, including spectropolarimetric observations. The nebular spectra are dominated by H{alpha} but also reveal emission lines from oxygen and calcium. Comparisons to synthetic nebular spectra indicate an initial progenitor mass of ~12M_{sun}_. We also note the presence of stable nickel in the nebular spectrum, and SN 2020jfo joins a small group of SNe that have inferred super-solar Ni/Fe ratios. Several years of pre-discovery data are examined, but no signs of pre-cursor activity is found. Pre-explosion Hubble Space Telescope imaging reveals a probable progenitor star, detected only in the reddest band (M_F814W_~-5.8) and is fainter than expected for stars in the 10-15M_{sun}_ range. There is thus some tension between the LC analysis, the nebular spectral modeling and the pre-explosion imaging. To compare and contrast, we present two additional core-collapse SNe monitored by the ZTF, which also have nebular H{alpha}-dominated spectra. This illustrates how the absence or presence of interaction with circumstellar material (CSM) affect both the LCs and in particular the nebular spectra. Type II SN 2020amv has a LC powered by CSM interaction, in particular after ~40-days when the LC is bumpy and slowly evolving. The late-time spectra show strong H{alpha} emission with a structure suggesting emission from a thin, dense shell. The evolution of the complex three-horn line profile is reminiscent of that observed for SN 1998S. Finally, SN 2020jfv has a poorly constrained early-time LC, but is of interest because of the transition from a hydrogen-poor Type IIb to a Type IIn, where the nebular spectrum after the light-curve rebrightening is dominated by H{alpha}, although with an intermediate line width.
- ID:
- ivo://CDS.VizieR/J/A+A/611/A58
- Title:
- SN 2007on and SN 2011iv light curves
- Short Name:
- J/A+A/611/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of ultraviolet (UV) to near-infrared observations of the fast-declining Type Ia supernovae (SNe Ia) 2007on and 2011iv, hosted by the Fornax cluster member NGC 1404. The B-band light curves of SN 2007on and SN 2011iv are characterised by {Delta}m15(B) decline-rate values of 1.96mag and 1.77mag, respectively. Although they have similar decline rates, their peak B- and H-band magnitudes differ by ~0.60mag and ~0.35mag, respectively. After correcting for the luminosity vs. decline rate and the luminosity vs. colour relations, the peak B-band and H-band light curves provide distances that differ by ~14% and ~9%, respectively. These findings serve as a cautionary tale for the use of transitional SNe Ia located in early-type hosts in the quest to measure cosmological parameters. Interestingly, even though SN 2011iv is brighter and bluer at early times, by three weeks past maximum and extending over several months, its B-V colour is 0.12mag redder than that of SN 2007on. To reconcile this unusual behaviour, we turn to guidance from a suite of spherical one-dimensional Chandrasekhar-mass delayed-detonation explosion models. In this context, ^56^Ni production depends on both the so-called transition density and the central density of the progenitor white dwarf. To first order, the transition density drives the luminosity-width relation, while the central density is an important second-order parameter. Within this context, the differences in the B-V colour evolution along the Lira regime suggest that the progenitor of SN 2011iv had a higher central density than SN 2007on.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/2440
- Title:
- SN with associated Planck CMB temperatures
- Short Name:
- J/MNRAS/445/2440
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using the Planck map of the cosmic microwave background (CMB) radiation, we have checked and confirmed the existence of a correlation between supernova (SN) redshifts, z_SN_, and CMB temperature fluctuations at the SNe locations, T_SN_, which we previously reported for the Wilkinson Microwave Anisotropy Probe data. The Pearson correlation coefficient for the Planck data is r=+0.38+/-0.08, which indicates that the correlation is statistically significant (the signal is about 5{sigma} above the noise level). The correlation becomes even stronger for the Type Ia subsample of SNe, r_Ia_=+0.45+/-0.09, whereas for the rest of the SNe it is vanishing. By checking the slopes of the regression lines T_SN_/z_SN_ for Planck's different frequency bands, we have also excluded the possibility of this anomaly being caused by the Sunyaev-Zeldovich effect. The remaining possibility is some, unaccounted for, contribution to the CMB from distant (z>0.3) foreground through either the integrated Sachs-Wolfe effect or thermal emission from intergalactic matter.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/2668
- Title:
- Soft X-ray emission of Type Ia SN progenitors
- Short Name:
- J/MNRAS/426/2668
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of Chandra observations of the position of 10 nearby (<25Mpc) Type Ia supernovae, taken before the explosions. No sources corresponding to progenitors were found in any of the observations. We calculated upper limits on the bolometric luminosities of the progenitors assuming blackbody X-ray spectra with temperatures of 30-150eV. This is inspired by the fact that luminous super-soft X-ray sources have been suggested as the direct progenitors of Type Ia supernovae. The upper limits of two supernovae in our sample are comparable to the luminosities of the brightest observed super-soft sources, ruling out such sources as the progenitors of these supernovae. In contrast to Liu et al. (2012ApJ...749..141L), we find that for SN2011fe we can rule out Eddington luminosity systems for blackbody temperatures as low as 40eV. Our findings are consistent with statistical studies comparing the observed Type Ia supernova rate to the number of super-soft sources or the integrated X-ray luminosity in external galaxies. This suggests that either the progenitors of Type Ia supernovae are not accreting, nuclear burning white dwarfs or that they do not look like the classical super-soft sources, e.g. because they are obscured.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A37
- Title:
- Spectral log of (i)PTF stripped-envelope SN
- Short Name:
- J/A+A/618/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of 507 spectra of 173 stripped-envelope (SE) supernovae (SNe) discovered by the untargeted Palomar Transient Factory (PTF) and intermediate PTF (iPTF) surveys. Our sample contains 55 TypeIIb SNe (SNeIIb), 45 TypeIb SNe (SNeIb), 56 TypeIc SNe (SNeIc), and 17 TypeIb/c SNe (SNeIb/c). We have compared the SE SN subtypes via measurements of the pseudo-equivalent widths (pEWs) and velocities of the HeI{lambda}{lambda}5876, 7065 and OI{lambda}7774 absorption lines. Consistent with previous work, we find that SNeIc show higher pEWs and velocities in OI{lambda}7774 compared to SNeIIb andIb. The pEWs of the HeI{lambda}{lambda}5876, 7065 lines are similar in SNeIb andIIb after maximum light. The HeI{lambda}{lambda}5876, 7065 velocities at maximum light are higher in SNeIb compared to SNeIIb. We identify an anticorrelation between the HeI{lambda}7065 pEW and OI{lambda}7774 velocity among SNeIIb andIb. This can be interpreted as a continuum in the amount of He present at the time of explosion.It has been suggested that SNeIb andIc have similar amounts of He, and that lower mixing could be responsible for hiding He in SNeIc. However, our data contradict this mixing hypothesis. The observed difference in the expansion rate of the ejecta around maximum light of SNeIc (V_m_=sqrt(2)E_k_/M_ej_~=15000km/s) and SNeIb (V_m_~=9000km/s) would imply an average He mass difference of ~1.4M_{sun}_, if the other explosion parameters are assumed to be unchanged between the SE SN subtypes. We conclude that SNeIc do not hide He but lose He due to envelope stripping.
- ID:
- ivo://CDS.VizieR/J/ApJ/699/L139
- Title:
- Spectral parameters of SNe Ia
- Short Name:
- J/ApJ/699/L139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the observables of 158 relatively normal Type Ia supernovae (SNe Ia) by dividing them into two groups in terms of the expansion velocity inferred from the absorption minimum of the SiII{lambda}6355 line in their spectra near B-band maximum brightness. One group ("Normal") consists of normal SNe Ia populating a narrow strip in the SiII velocity distribution, with an average expansion velocity <{nu}>=10600+/-400km/s near B maximum; the other group ("HV") consists of objects with higher velocities, {nu}>~11800km/s. Compared with the Normal group, the HV one shows a narrower distribution in both the peak luminosity and the luminosity decline rate {Delta}m_15_. In particular, their B-V colors at maximum brightness are found to be on average redder by ~0.1mag, suggesting that they either are associated with dusty environments or have intrinsically red B-V colors. The HV SNe Ia are also found to prefer a lower extinction ratio RV~1.6 (versus ~2.4 for the Normal ones). Applying such an absorption-correction dichotomy to SNe Ia of these two groups remarkably reduces the dispersion in their peak luminosity from 0.178mag to only 0.125mag.
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A142
- Title:
- Spectra of 5 Type II supernovae
- Short Name:
- J/A+A/555/A142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Core-collapse Supernovae (CC-SNe) descend from progenitors more massive than about 8M_{sun}_. Because of the young age of the progenitors, the ejecta may eventually interact with the circumstellar medium (CSM) via highly energetic processes detectable in the radio, X-ray, ultraviolet (UV) and, sometimes, in the optical domains. In this paper we present ultraviolet, optical and near infrared observations of five type II SNe, namely SNe 2009dd, 2007pk, 2010aj, 1995ad, and 1996W. Together with few other SNe they form a group of moderately luminous type II events. We investigate the photometric similarities and differences among these bright objects. We also attempt to characterise them by analysing the spectral evolutions, in order to find some traces of CSM-ejecta interaction. We collected photometry and spectroscopy with several telescopes in order to construct well-sampled light curves and spectral evolutions from the photospheric to the nebular phases. Both photometry and spectroscopy indicate a degree of heterogeneity in this sample. Modelling the data of SNe 2009dd, 2010aj and 1995ad allows us to constrain the explosion parameters and the properties of the progenitor stars. The light curves have luminous peak magnitudes (-16.95<M_B}_-18.70). The ejected masses of ^56^Ni for three SNe span a wide range of values (2.8x10^-2^M_{sun}<M(^56^Ni)<1.4x10^-1^M_{sun}_), while for a fourth (SN2010aj) we could determine a stringent upper limit (7x10^-3^M_{sun}_). Clues of interaction, such as the presence of high velocity (HV) features of the Balmer lines, are visible in the photospheric spectra of SNe 2009dd and 1996W. For SN2007pk we observe a spectral transition from a type IIn to a standard type II SN. Modelling the observations of SNe 2009dd, 2010aj and 1995ad with radiation hydrodynamics codes, we infer kinetic plus thermal energies of about 0.2-0.5 foe, initial radii of 2-5x10^13^cm and ejected masses of ~5.0-9.5M_{sun}_. These values suggest moderate-mass, super-asymptotic giant branch (SAGB) or red super-giants (RSG) stars as SN precursors, in analogy with other luminous type IIP SNe 2007od and 2009bw.
