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Start Over Subject supernovae Validation Level 2
251. R-band observations of PTF 10vgv
ID:
ivo://CDS.VizieR/J/ApJ/747/L5
Title:
R-band observations of PTF 10vgv
Short Name:
J/ApJ/747/L5
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discovery of PTF 10vgv, a Type Ic supernova (SN) detected by the Palomar Transient Factory, using the Palomar 48 inch telescope (P48). R-band observations of the PTF 10vgv field with P48 probe the SN emission from its very early phases (about two weeks before R-band maximum) and set limits on its flux in the week prior to the discovery. Our sensitive upper limits and early detections constrain the post-shock-breakout luminosity of this event. Via comparison to numerical (analytical) models, we derive an upper-limit of R<~4.5R_{sun}_ (R<~1R_{sun}_) on the radius of the progenitor star, a direct indication in favor of a compact Wolf-Rayet star. Applying a similar analysis to the historical observations of SN 1994I yields R<~1/4R_{sun}_ for the progenitor radius of this SN.
252. R-band PTF observations of SNe IIb
ID:
ivo://CDS.VizieR/J/ApJ/811/117
Title:
R-band PTF observations of SNe IIb
Short Name:
J/ApJ/811/117
Date:
21 Oct 2021
Publisher:
CDS
Description:
The progenitor stars of several Type IIb supernovae (SNe) show indications of extended hydrogen envelopes. These envelopes might be the outcome of luminous energetic pre-explosion events, so-called precursor eruptions. We use the Palomar Transient Factory (PTF) pre-explosion observations of a sample of 27 nearby SNe IIb to look for such precursors during the final years prior to the SN explosion. No precursors are found when combining the observations in 15-day bins, and we calculate the absolute-magnitude-dependent upper limit on the precursor rate. At the 90% confidence level, SNe IIb have on average <0.86 precursors as bright as an absolute R-band magnitude of -14 in the final 3.5 years before the explosion and <0.56 events over the final year. In contrast, precursors among SNe IIn have a >~5 times higher rate. The kinetic energy required to unbind a low-mass stellar envelope is comparable to the radiated energy of a few-weeks-long precursor that would be detectable for the closest SNe in our sample. Therefore, mass ejections, if they are common in such SNe, are radiatively inefficient or have durations longer than months. Indeed, when using 60-day bins, a faint precursor candidate is detected prior to SN 2012cs (~2% false-alarm probability). We also report the detection of the progenitor of SN 2011dh that does not show detectable variability over the final two years before the explosion. The suggested progenitor of SN 2012P is still present, and hence is likely a compact star cluster or an unrelated object.
253. Reddening law of type Ia supernovae
ID:
ivo://CDS.VizieR/J/A+A/529/L4
Title:
Reddening law of type Ia supernovae
Short Name:
J/A+A/529/L4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We employ 76 type Ia supernovae (SNe Ia) with optical spectrophotometry within 2.5 days of B-band maximum light obtained by the Nearby Supernova Factory to derive the impact of Si and Ca features on the supernovae intrinsic luminosity and determine a dust reddening law. We use the equivalent width of SiII {lambda}4131 in place of the light curve stretch to account for first-order intrinsic luminosity variability. The resulting empirical spectral reddening law exhibits strong features that are associated with CaII and SiII {lambda}6355. After applying a correction based on the CaII H&K equivalent width we find a reddening law consistent with a Cardelli extinction law. Using the same input data, we compare this result to synthetic rest-frame UBVRI-like photometry to mimic literature observations.
254. Redshifts of 65 CANDELS supernovae
ID:
ivo://CDS.VizieR/J/AJ/148/13
Title:
Redshifts of 65 CANDELS supernovae
Short Name:
J/AJ/148/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed a total area of ~0.25deg^2^ with ~900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z~2.5. We classify ~24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z=2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only ~3Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation (<500Myr). Combining the CANDELS rates with all available SN Ia rate measurements in the literature we find that this prompt SN Ia fraction is f_p_=0.53_stat0.10sys0.26_^+/-0.09 +/-0.10^, consistent with a delay time distribution that follows a simple t^-1^ power law for all times t>40Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z>1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20% of all SN Ia explosions--though further analysis and larger samples will be needed to examine that suggestion.
255. Relations between spectra and colors of SNe Ia
ID:
ivo://CDS.VizieR/J/ApJ/742/89
Title:
Relations between spectra and colors of SNe Ia
Short Name:
J/ApJ/742/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
To understand how best to use observations of Type Ia supernovae (SNe Ia) to obtain precise and accurate distances, we investigate the relations between spectra of SNe Ia and their intrinsic colors. Using a sample of 1630 optical spectra of 255 SNe, based primarily on data from the CfA Supernova Program, we examine how the velocity evolution and line strengths of SiII(6355) and CaII H&K are related to the B-V color at peak brightness. We find that the maximum-light velocity of SiII6355 and CaII H&K and the maximum-light pseudo-equivalent width of SiII6355 are correlated with intrinsic color, with intrinsic color having a linear relation with the SiII6355 measurements. CaII H&K does not have a linear relation with intrinsic color, but lower-velocity SNe tend to be intrinsically bluer. Combining the spectroscopic measurements does not improve intrinsic color inference. The intrinsic color scatter is larger for higher-velocity SNe Ia - even after removing a linear trend with velocity - indicating that lower-velocity SNe Ia are more "standard crayons". Employing information derived from SN Ia spectra has the potential to improve the measurements of extragalactic distances and the cosmological properties inferred from them.
256. Relationships between SNe Ia and the host galaxies
ID:
ivo://CDS.VizieR/J/ApJ/848/56
Title:
Relationships between SNe Ia and the host galaxies
Short Name:
J/ApJ/848/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use a sample of 1338 spectroscopically confirmed and photometrically classified Type Ia supernovae (SNe Ia) sourced from Carnegie Supernova Project, Center for Astrophysics Supernova Survey, Sloan Digital Sky Survey-II, and SuperNova Legacy Survey SN samples to examine the relationships between SNe Ia and the galaxies that host them. Our results provide confirmation with improved statistical significance that SNe Ia, after standardization, are on average more luminous in massive hosts (significance >5{sigma}), and decline more rapidly in massive hosts (significance >9{sigma}) and in hosts with low specific star formation rates (significance >8{sigma}). We study the variation of these relationships with redshift and detect no evolution. We split SNe Ia into pairs of subsets that are based on the properties of the hosts and fit cosmological models to each subset. Including both systematic and statistical uncertainties, we do not find any significant shift in the best-fit cosmological parameters between the subsets. Among different SN Ia subsets, we find that SNe Ia in hosts with high specific star formation rates have the least intrinsic scatter ({sigma}_int_=0.08+/-0.01) in luminosity after standardization.
257. Relativistic EOS for core-collapse SN simulations
ID:
ivo://CDS.VizieR/J/ApJS/197/20
Title:
Relativistic EOS for core-collapse SN simulations
Short Name:
J/ApJS/197/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
We construct the equation of state (EOS) of dense matter covering a wide range of temperature, proton fraction, and density for the use of core-collapse supernova simulations. The study is based on the relativistic mean-field (RMF) theory, which can provide an excellent description of nuclear matter and finite nuclei. The Thomas-Fermi approximation in combination with assumed nucleon distribution functions and a free energy minimization is adopted to describe the non-uniform matter, which is composed of a lattice of heavy nuclei. We treat the uniform matter and non-uniform matter consistently using the same RMF theory. We present two sets of EOS tables, namely EOS2 and EOS3. EOS2 is an update of our earlier work published in 1998 (EOS1; see 1998NuPhA.637..435S and 1998PThPh.100.1013S), where only the nucleon degree of freedom is taken into account. EOS3 includes additional contributions from {Lambda} hyperons. The effect of {Lambda} hyperons on the EOS is negligible in the low-temperature and low-density region, whereas it tends to soften the EOS at high density. In comparison with EOS1, EOS2 and EOS3 have an improved design of ranges and grids, which covers the temperature range T=0.1-10^2.6^MeV with the logarithmic grid spacing {delta}log_10_(T/[MeV])=0.04 (92 points including T=0), the proton fraction range Y_p_=0-0.65 with the linear grid spacing {Delta}Y_p_=0.01 (66 points), and the density range {rho}_B_=10^5.1^-10^16^g/cm^3^ with the logarithmic grid spacing {Delta}log_10_({rho}_B_/[g/cm^3^])=0.1 (110 points).
258. Restframe I-band light curves of SN Ia
ID:
ivo://CDS.VizieR/J/A+A/437/789
Title:
Restframe I-band light curves of SN Ia
Short Name:
J/A+A/437/789
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a novel technique for fitting restframe I-band light curves on a data set of 42 type Ia supernovae (SNe Ia). Using the result of the fit, we construct a Hubble diagram with 26 SNe from the subset at 0.01<z<0.1. Adding two SNe at z~0.5 yields results consistent with a flat Lambda-dominated "concordance universe'' (Omega_M_,Omega_Lambda_)=(0.25, 0.75). For one of these, SN 2000fr, new near infrared data are presented. The high redshift supernova NIR data are also used to test for systematic effects in the use of SNe Ia as distance estimators. A flat, Lambda=0, universe where the faintness of supernovae at z~0.5 is due to grey dust homogeneously distributed in the intergalactic medium is disfavoured based on the high-z Hubble diagram using this small data-set. However, the uncertainties are large and no firm conclusion may be drawn. We explore the possibility of setting limits on intergalactic dust based on B-I and B-V colour measurements, and conclude that about 20 well measured SNe are needed to give statistically significant results. We also show that the high redshift restframe I-band data points are better fit by light curve templates that show a prominent second peak, suggesting that they are not intrinsically underluminous.
259. Revised photometry of SNIa
ID:
ivo://CDS.VizieR/J/A+A/317/423
Title:
Revised photometry of SNIa
Short Name:
J/A+A/317/423
Date:
21 Oct 2021
Publisher:
CDS
Description:
Re-calibrated B magnitudes and (B-V) colors for the stars of the local sequences used at Asiago in the seventies as reference for the SN photometry are given in table3. For comparison, also the Asiago original data are given. Identification charts are found in the original papers.
260. Revised redshifts of the Pantheon supernovae Ia
ID:
ivo://CDS.VizieR/J/ApJ/902/14
Title:
Revised redshifts of the Pantheon supernovae Ia
Short Name:
J/ApJ/902/14
Date:
17 Mar 2022 14:41:40
Publisher:
CDS
Description:
Redshifts used in current cosmological supernova samples are measured using two primary techniques, one based on well-measured host galaxy spectral lines and the other based on supernova-dominated spectra. Here, we construct an updated Pantheon catalog with revised redshifts, redshift sources, and estimated uncertainties for the entire sample to investigate whether these two techniques yield consistent results. The best-fit cosmological parameters using these two measurement techniques disagree, with a supernova-only sample producing {Omega}_m_ 3.2{sigma} higher and H_0_ 2.5{sigma} lower than a hostz-only sample, and we explore several possible sources of bias that could result from using the lower-precision supernova-dominated redshifts. In a pilot study, we show that using a host redshift-only subsample will generically produce lower {Omega}_m_ and matter density {Omega}_m_h^2^ and slightly higher H_0_ than previous analysis which, for the Pantheon data set, could result in supernova and cosmic microwave background measurements agreeing on {Omega}_m_h^2^ despite tension in H_0_. To obtain rigorous results, though, the Pantheon catalog should be improved by obtaining host spectra for supernovae that have faded, and future surveys should be designed to use host galaxy redshifts rather than lower-precision methods.