- ID:
- ivo://CDS.VizieR/J/MNRAS/411/1367
- Title:
- 12mm line survey towards W28 SNR
- Short Name:
- J/MNRAS/411/1367
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 12mm Mopra observations of dense molecular gas towards the W28 supernova remnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-ray sources detected by the HESS telescopes, which likely trace the cosmic rays from W28 and possibly other sources in the region. Using the NH_3_ inversion transitions we reveal several dense cores inside the molecular clouds,
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/732/65
- Title:
- Modeling the local velocity field with SNIa
- Short Name:
- J/ApJ/732/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We apply statistically rigorous methods of nonparametric risk estimation to the problem of inferring the local peculiar velocity field from nearby Type Ia supernovae (SNIa). We use two nonparametric methods -weighted least squares (WLS) and coefficient unbiased (CU)- both of which employ spherical harmonics to model the field and use the estimated risk to determine at which multipole to truncate the series. We show that if the data are not drawn from a uniform distribution or if there is power beyond the maximum multipole in the regression, a bias is introduced on the coefficients using WLS. CU estimates the coefficients without this bias by including the sampling density making the coefficients more accurate but not necessarily modeling the velocity field more accurately. After applying nonparametric risk estimation to SNIa data, we find that there are not enough data at this time to measure power beyond the dipole. The WLS Local Group bulk flow is moving at 538+/-86km/s toward (l,b)=(258+/-10{deg},36+/-11{deg}) and the CU bulk flow is moving at 446+/-101km/s toward (l,b)=(273+/-11{deg},46+/-8{deg}). We find that the magnitude and direction of these measurements are in agreement with each other and previous results in the literature.
- ID:
- ivo://CDS.VizieR/J/ApJS/237/13
- Title:
- Models and yields of 13-120M_{sun}_ massive stars
- Short Name:
- J/ApJS/237/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new grid of presupernova models of massive stars extending in mass between 13 and 120M_{sun}_, covering four metallicities (i.e., [Fe/H]=0, -1, -2, and -3) and three initial rotation velocities (i.e., 0, 150, and 300km/s). The explosion has been simulated following three different assumptions in order to show how the yields depend on the remnant mass-initial mass relation. An extended network from H to Bi is fully coupled to the physical evolution of the models. The main results can be summarized as follows. (a) At solar metallicity, the maximum mass exploding as a red supergiant (RSG) is of the order of 17M_{sun}_ in the nonrotating case, with the more massive stars exploding as Wolf-Rayet (WR) stars. All rotating models, conversely, explode as WR stars. (b) The interplay between the core He-burning and the H-burning shell, triggered by the rotation-induced instabilities, drives the synthesis of a large primary amount of all the products of CNO, not just ^14^N. A fraction of them greatly enriches the radiative part of the He core (and is responsible for the large production of F), and a fraction enters the convective core, leading therefore to an important primary neutron flux able to synthesize heavy nuclei up to Pb. (c) In our scenario, remnant masses of the order of those inferred from the first detections of gravitational waves (GW 150914, GW 151226, GW 170104, GW 170814) are predicted at all metallicities for none or moderate initial rotation velocities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/425/1696
- Title:
- Models of a young star cluster ejecta
- Short Name:
- J/MNRAS/425/1696
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have computed with a fine time grid the evolution of the elemental abundances of He, C, N and O ejected by young (t<20Myr) and massive (M=10^6^M_{sun}_) coeval stellar cluster with a Salpeter initial mass function (IMF) over a wide range of initial abundances. Our computations incorporate the mass loss from massive stars (M>=30M_{sun}_) during their wind phase including the Wolf-Rayet phase and the ejecta from the core-collapse supernovae. We find that during the Wolf-Rayet phase (t<5Myr) the cluster ejecta composition suddenly becomes vastly overabundant in N for all initial abundances and in He, C and O for initial abundances higher than one-fifth of the solar. The C and O abundances in the cluster ejecta can reach over 50 times the solar value with important consequences for the chemical and hydrodynamical evolution of the surrounding interstellar medium.
- ID:
- ivo://CDS.VizieR/J/A+A/558/A131
- Title:
- Model spectra of hot stars at the pre-SN stage
- Short Name:
- J/A+A/558/A131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the fundamental properties of core-collapse Supernova (SN) progenitors from single stars at solar metallicity. We combine Geneva stellar evolutionary models with initial masses of Mini=20-120M_{sun}_ with atmospheric/wind models using CMFGEN. We provide synthetic photometry and high-resolution spectra of hot stars at the pre-SN stage. For Mini=9-20M_{sun}_, we supplement our analysis using publicly available MARCS model atmospheres of RSGs. We employ observational criteria of spectroscopic classification and find that massive stars, depending on Mini and rotation, end their lives as red supergiants (RSG), yellow hypergiants (YHG), luminous blue variables (LBV), and Wolf-Rayet (WR) stars of the WN and WO spectral types. For rotating models, we obtain the following types of SN progenitors: WO1-3 (Mini<=32M_{sun}_), WN10-11 (25<Mini< 32M_{sun}_), LBV (20<=Mini<25M_{sun}_), G1 Ia+ (18<Mini<20M_{sun}_), and RSGs (9<=Mini<=18M_{sun}_). For non-rotating models, we find spectral types WO1-3 (Mini>40M_{sun}_), WN7-8 (25<Mini<=40M_{sun}_), WN11h/LBV (20<Mini<=25M_{sun}_), and RSGs (9<=Mini<=20M_{sun}_). Our rotating models indicate that SN IIP progenitors are all RSG, SN IIL/b progenitors are 56% LBVs and 44% YHGs, SN Ib progenitors are 96% WN10-11 and 4% WOs, and SN Ic progenitors are all WO stars. We find that not necessarily the most massive and luminous SN progenitors are the brighter ones in a given filter. We show that SN IIP progenitors (RSGs) are bright in the RIJHK_S filters and faint in the UB filters. SN IIL/b progenitors (LBVs and YHGs), and SN Ib progenitors (WNs) are relatively bright in optical/IR filters, while SN Ic progenitors (WOs) are faint in all optical filters. We argue that SN Ib and Ic progenitors from single stars should be undetectable in the available pre-explosion images with the current magnitude limits, in agreement with observational results.
- ID:
- ivo://CDS.VizieR/J/MNRAS/424/2841
- Title:
- Morphology of supernova host galaxies
- Short Name:
- J/MNRAS/424/2841
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents an analysis of core-collapse supernova distributions in isolated and interacting host galaxies, paying close attention to the selection effects involved in conducting host galaxy supernova studies. When taking into account all of the selection effects within our host galaxy sample, we draw the following conclusions. 1. Within interacting, or 'disturbed', systems there is a real, and statistically significant, increase in the fraction of stripped-envelope supernovae in the central regions. A discussion into what may cause this increased fraction, compared to the more common Type IIP supernovae and Type II supernovae without subclassifications, is presented. Selection effects are shown not to drive this result, and so we propose that this study provides direct evidence for a high-mass weighted initial mass function within the central regions of disturbed galaxies. 2. Within 'undisturbed' spiral galaxies the radial distribution of Type Ib and Type Ic supernovae is statistically very different, with the latter showing a more centrally concentrated distribution. This could be driven by metallicity gradients in these undisturbed galaxies, or radial variations in other properties (binarity or stellar rotation) driving envelope loss in progenitor stars. This result is not found in 'disturbed' systems, where the distributions of Type Ib and Ic supernovae are consistent.
- ID:
- ivo://CDS.VizieR/J/ApJ/886/40
- Title:
- Most luminous SPIRITS IR transients follow-up obs.
- Short Name:
- J/ApJ/886/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a systematic study of the most luminous (MIR [Vega magnitudes] brighter than -14) infrared (IR) transients discovered by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) between 2014 and 2018 in nearby galaxies (D<35Mpc). The sample consists of nine events that span peak IR luminosities of M_[4.5],peak_ between -14 and -18.2, show IR colors between 0.2<([3.6]-[4.5])<3.0, and fade on timescales between 55d<t_fade_<480d. The two reddest events (A_V_>12) show multiple, luminous IR outbursts over several years and have directly detected, massive progenitors in archival imaging. With analyses of extensive, multiwavelength follow-up, we suggest the following possible classifications: five obscured core-collapse supernovae (CCSNe), two erupting massive stars, one luminous red nova, and one intermediate-luminosity red transient. We define a control sample of all optically discovered transients recovered in SPIRITS galaxies and satisfying the same selection criteria. The control sample consists of eight CCSNe and one Type Iax SN. We find that 7 of the 13 CCSNe in the SPIRITS sample have lower bounds on their extinction of 2<A_V_<8. We estimate a nominal fraction of CCSNe in nearby galaxies that are missed by optical surveys as high as 38.5_-21.9_^+26.0^% (90% confidence). This study suggests that a significant fraction of CCSNe may be heavily obscured by dust and therefore undercounted in the census of nearby CCSNe from optical searches.
- ID:
- ivo://CDS.VizieR/J/A+A/415/863
- Title:
- Mount Stromlo Abell Cluster Supernova Search
- Short Name:
- J/A+A/415/863
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 1 lists SNe discovered by the Mount Stromlo Abell Cluster Supernova Search. The SNIa? were classified through the goodness of fit of the template light curves and hence could be SNe of another type that have been misclassified. Those SNe designated nIa were deemed not to be SNIa through the template fits and were not investigated further. Table 3 contains Maximum light magnitudes, {Delta}m15 values and distances derived from the template light curve fitting technique for those SNe from the Mount Stromlo Abell Cluster Supernova Search deemed to be SNIa, as well as those from Phillips (1999AJ....118.1766P) The subdirectory "comp" contains the files with calibrated magnitudes for the local standard stars found in the field of each of the supernovae from the Mount Stromlo Abell Cluster Supernova Search. The numbering of these stars corresponds to that found in the finding charts of each of these fields. These are found online at EDP Sciences. For each local standard, their Cousins B, V, R and I magnitudes are given, as is the error in the magnitude estimate. The subdirectory "flux" contains the files with calibrated fluxes for the supernovae discovered in the Mount Stromlo Abell Cluster Supernova Search. For each supernova, the MACHO VM, RM magnitudes and Cousins B, V, R and I fluxes are given (when available), as are the errors in the derived fluxes. One unit flux is equivalent to 25th magnitude. The subdirectory "mag" contains the files with calibrated magnitudes for the supernovae discovered in the Mount Stromlo Abell Cluster Supernova Search. For each supernova, the MACHO VM, RM magnitudes and Cousins B, V, R and I magnitudes are given (when available), as is the upper and lower errors in the derived magnitudes.
- ID:
- ivo://CDS.VizieR/J/MNRAS/394/21
- Title:
- Multi-epoch spectroscopy of SN 1994W
- Short Name:
- J/MNRAS/394/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multi-epoch quantitative spectroscopic analysis of the Type IIn supernova (Type IIn SN) 1994W, an event interpreted by Chugai et al. (2004MNRAS.352.1213C) as stemming from the interaction between the ejecta of a SN and a 0.4M_{sun}_ circumstellar shell ejected 1.5yr before core collapse.
- ID:
- ivo://CDS.VizieR/J/ApJ/817/60
- Title:
- Multiply imaged supernova Refsdal
- Short Name:
- J/ApJ/817/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Supernova "Refsdal", multiply imaged by cluster MACS1149.5+2223, represents a rare opportunity to make a true blind test of model predictions in extragalactic astronomy, on a timescale that is short compared to a human lifetime. In order to take advantage of this event, we produced seven gravitational lens models with five independent methods, based on Hubble Space Telescope (HST) Hubble Frontier Field images, along with extensive spectroscopic follow-up observations by HST, the Very Large and the Keck Telescopes. We compare the model predictions and show that they agree reasonably well with the measured time delays and magnification ratios between the known images, even though these quantities were not used as input. This agreement is encouraging, considering that the models only provide statistical uncertainties, and do not include additional sources of uncertainties such as structure along the line of sight, cosmology, and the mass sheet degeneracy. We then present the model predictions for the other appearances of supernova "Refsdal". A future image will reach its peak in the first half of 2016, while another image appeared between 1994 and 2004. The past image would have been too faint to be detected in existing archival images. The future image should be approximately one-third as bright as the brightest known image (i.e., H_AB_~25.7mag at peak and H_AB_~26.7mag six months before peak), and thus detectable in single-orbit HST images. We will find out soon whether our predictions are correct.
