The Carnegie Supernova Project II. Observations of the intermediate luminosity red transient SNhunt120
M. D. Stritzinger, F. Taddia, M. Fraser, T. M. Tauris, N. B. Suntzeff, C. Contreras, S Drybye, L. Galbany, S. Holmbo, N. Morrell, M. M. Phillips, J. L. Prieto, … 展开作者
M. D. Stritzinger, F. Taddia, M. Fraser, T. M. Tauris, N. B. Suntzeff, C. Contreras, S Drybye, L. Galbany, S. Holmbo, N. Morrell, M. M. Phillips, J. L. Prieto, J. Anais, C. Ashall, E. Baron, C. R. Burns, P. Hoeflich, E. Y. Hsiao, E. Karamehmetoglu, T. J. Moriya, M. T. Botticella, A. Campillay, S. Castellon, C. Gonzalez, M. L. Pumo, S. Torres-Robledo
备注：
Paper 1 of a series of 2. Eight pages of text, 14 figures, and 10 tables. Replaced to match the version published on A&A
We present multi-wavelength observations of two gap transients followed by the Carnegie Supernova Project-II and supplemented with data obtained by a number of different programs. Here in the first of two papers, we focus on the intermediate luminosity red transient (ILRT) designated SNhunt120, while in a companion paper we examine the luminous red novae AT 2014ej. Our data set for SNhunt120 consists of an early optical discovery, estimated to be within 3 days after outburst, the subsequent optical and near-infrared broadband followup extending over a $\sim$2 month period, two visual- and two near-infrared wavelength spectra, and Spitzer Space Telescope observations extending from early ($+$28 d) to late ($+$1155 d) phases. SNhunt120 resembles other ILRTs such as NGC 300-2008-OT and SN 2008S, and like these other ILRTs, SNhunt120 exhibits prevalent mid-infrared emission at both early and late phases. From the comparison of SNhunt120 and other ILRTs to electron-capture supernova simulations, we find that the current models underestimate the explosion kinetic energy and thereby produce synthetic light curves that over-estimate the luminosity. Finally, examination of pre-outburst Hubble Space Telescope images yields no progenitor detection.
The first phase of the Carnegie Supernova Project (CSP-I) was a dedicated supernova follow-up program based at the Las Campanas Observatory that collected science data of young, low-redshift supernovae between 2004 and 2009. Presented in this paper is the CSP-I photometric data release of low-redshift stripped-envelope core-collapse supernovae. The data consist of optical (uBgVri) photometry of 34 objects, with a subset of 26 having near-infrared (YJH) photometry. Twenty objects have optical pre-maximum coverage with a subset of 12 beginning at least five days prior to the epoch of B-band maxi…
We use the spectroscopy and homogeneous photometry of 97 Type Ia supernovae obtained by the \emph{Carnegie Supernova Project} as well as a subset of 36 Type Ia supernovae presented by Zheng et al. (2018) to examine maximum-light correlations in a four-dimensional (4-D) parameter space: $B$-band absolute magnitude, $M_B$, \ion{Si}{2}~$\lambda6355$ velocity, \vsi, and \ion{Si}{2} pseudo-equivalent widths pEW(\ion{Si}{2}~$\lambda6355$) and pEW(\ion{Si}{2}~$\lambda5972$). It is shown using Gaussian mixture models (GMMs) that the original four groups in the Branch diagram are well-defined and robus…
We present the $H$-band wavelength region of thirty post-maximum light near-infrared (NIR) spectra of fourteen transitional and sub-luminous type Ia supernovae (SNe Ia), extending from $+$5d to +20d relative to the epoch of $B$-band maximum. We introduce a new observable, the blue-edge velocity, $v_{edge}$, of the prominent Fe/Co/Ni-peak $H$-band emission feature which is quantitatively measured. The $v_{edge}$ parameter is found to slowly decrease over sub-type ranging from around $-$13,000km/s for transitional SNe~Ia, down to $-$5,000km/s for the sub-luminous SNe Ia. Furthermore, inspection …
We present $81$ near-infrared (NIR) spectra of $30$ Type II supernovae (SNe II) from the Carnegie Supernova Project-II (CSP-II), the largest such dataset published to date. We identify a number of NIR features and characterize their evolution over time. The NIR spectroscopic properties of SNe II fall into two distinct groups. This classification is first based on the strength of the He I $\lambda1.083\,μ$m absorption during the plateau phase; SNe II are either significantly above (spectroscopically strong) or below $50$ angstroms (spectroscopically weak) in pseudo equivalent width. However bet…
The present study is the first of a series of three papers where we characterise the type II supernovae (SNe~II) from the Carnegie Supernova Project-I to understand their diversity in terms of progenitor and explosion properties. In this first paper, we present bolometric light curves of 74 SNe~II. We outline our methodology to calculate the bolometric luminosity, which consists of the integration of the observed fluxes in numerous photometric bands ($uBgVriYJH$) and black-body (BB) extrapolations to account for the unobserved flux at shorter and longer wavelengths. BB fits were performed usin…
Stripped-envelope (SE) supernovae (SNe) include H-poor (Type IIb), H-free (Type Ib) and He-free (Type Ic) events thought to be associated with the deaths of massive stars. The exact nature of their progenitors is a matter of debate. Here we present the analysis of the light curves of 34 SE SNe published by the Carnegie Supernova Project (CSP-I), which are unparalleled in terms of photometric accuracy and wavelength range. Light-curve parameters are estimated through the fits of an analytical function and trends are searched for among the resulting fit parameters. We found a tentative correlati…
The Carnegie Supernova Project-II (CSP-II) was an NSF-funded, four-year program to obtain optical and near-infrared observations of a "Cosmology" sample of $\sim100$ Type Ia supernovae located in the smooth Hubble flow ($0.03 \lesssim z \lesssim 0.10$). Light curves were also obtained of a "Physics" sample composed of 90 nearby Type Ia supernovae at $z \leq 0.04$ selected for near-infrared spectroscopic time-series observations. The primary emphasis of the CSP-II is to use the combination of optical and near-infrared photometry to achieve a distance precision of better than 5%. In this paper, …
We aim to improve upon contemporary methods to estimate host-galaxy reddening of stripped-envelope (SE) supernovae (SNe). To this end the Carnegie Supernova Project (CSP-I) SE SNe photometry data release, consisting of nearly three dozen objects, is used to identify a minimally reddened sub-sample for each traditionally defined spectroscopic sub-types (i.e, SNe~IIb, SNe~Ib, SNe~Ic). Inspection of the optical and near-infrared (NIR) colors and color evolution of the minimally reddened sub-samples reveals a high degree of homogeneity, particularly between 0d to +20d relative to B-band maximum. T…
We present optical and near-infrared photometry and spectroscopy of the Type IIn supernova (SN) 2014ab, obtained by the Carnegie Supernova Project II (CSP-II) and initiated immediately after its optical discovery. We also present mid-infrared photometry obtained by the Wide-field Infrared Survey Explorer (WISE) satellite extending from 56 days prior to the optical discovery to over 1600 days. The light curve of SN 2014ab evolves slowly, while the spectra exhibit strong emission features produced from the interaction between rapidly expanding ejecta and dense circumstellar matter. The light cur…
SNe II show great photometric and spectroscopic diversity which is attributed to the varied physical characteristics of their progenitor and explosion properties. In this study, the third of a series of papers where we analyse a sample of SNe II observed by the Carnegie Supernova Project-I, we present correlations between their observed and physical properties. Our analysis shows that explosion energy is the physical property that correlates with the highest number of parameters. We recover previously suggested relationships between the hydrogen-rich envelope mass and the plateau duration, and…
Linking supernovae to their progenitors is a powerful method for furthering our understanding of the physical origin of their observed differences, while at the same time testing stellar evolution theory. In this second study of a series of three papers where we characterise SNe II to understand their diversity, we derive progenitor properties (initial and ejecta masses, and radius), explosion energy, $^{56}$Ni mass, and its degree of mixing within the ejecta for a large sample of SNe II. This dataset was obtained by the Carnegie Supernova Project-I and is characterised by a high cadence of th…
We present a multi-wavelength photometric and spectroscopic analysis of thirteen "Super-Chandrasekhar Mass"/2003fg-like type Ia Supernova (SNe~Ia). Nine of these objects were observed by the Carnegie Supernova Project. 2003fg-like have slowly declining light curves ($Δm_{15}$(B) $<$1.3 mag), and peak absolute $B$-band magnitudes between $-19<M_{B}<-21$~mag. Many 2003fg-like are located in the same part of the luminosity width relation as normal SNe~Ia. In the optical $B$ and $V$ bands, 2003fg-like look like normal SNe~Ia, but at redder wavelengths they diverge. Unlike other luminous SNe~Ia, 20…
We present optical and near-infrared broadband photometry and optical spectra of AT 2014ej from the the Carnegie Supernova Project-II. These observations are complemented with data from the CHilean Automatic Supernova sEarch, the Public ESO Spectroscopic Survey of Transient Objects, and from the Backyard Observatory Supernova Search. Observational signatures of AT 2014ej reveal that it is similar to other members of the gap-transient subclass known as luminous red novae (LRNe), including the ubiquitous double hump light curve and spectral properties akin to the LRN SN 2017jfs. A medium-dispers…
We present bolometric light curves constructed from multi-wavelength photometry of Type Ia supernovae (SNe Ia) from the Carnegie Supernova Project and the CfA Supernova Group, using near-infrared observations to provide robust constraints on host galaxy dust extinction. This set of light curves form a well-measured reference set for comparison with theoretical models. Ejected mass and synthesized $^{56}$Ni mass are inferred for each SN Ia from its bolometric light curve using a semi-analytic Bayesian light curve model, and fitting formulae provided in terms of light curve width parameters from…
We present 75 near-infrared (NIR; 0.8$-$2.5 $μ$m) spectra of 34 stripped-envelope core-collapse supernovae (SESNe) obtained by the Carnegie Supernova Project-II (CSP-II), encompassing optical spectroscopic Types IIb, Ib, Ic, and Ic-BL. The spectra range in phase from pre-maximum to 80 days past maximum. This unique data set constitutes the largest NIR spectroscopic sample of SESNe to date. NIR spectroscopy provides observables with additional information that is not available in the optical. Specifically, the NIR contains the resonance lines of He I and allows a more detailed look at whether T…
We present a study of observed Type II supernova (SN~II) colours using optical/near-infrared photometric data from the \textit{Carnegie Supernovae Project-I}. We analyse four colours ($B-V$, $u-g$, $g-r$, and $g-Y$) and find that SN~II colour curves can be described by two linear regimes during the photospheric phase. The first ($s_{\rm 1,colour}$) is steeper and has a median duration of $\sim 40$ days. The second, shallower slope ($s_{\rm 2,colour}$) lasts until the end of the "plateau" ($\sim 80$ days). The two slopes correlate in the sense that steeper initial colour curves also imply steep…
We present ultra-violet to mid-infrared observations of the long-lasting Type IIn supernova (SN) 2013L obtained by the Carnegie Supernova Project II (CSP-II). The spectra of SN 2013L are dominated by H emission features characterized by three components attributed to different regions. A unique feature of this Type IIn SN is that the blue shifted line profile is dominated by the macroscopic velocity of the expanding shock wave of the SN. We are therefore able to trace the evolution of the shock velocity in the dense and partially opaque circumstellar medium (CSM), from $\sim 4800~km~s^{-1}$ at…
We present an updated analysis of the intrinsic colors of SNe Ia using the latest data release of the Carnegie Supernova Project. We introduce a new light-curve parameter very similar to stretch that is better suited for fast-declining events, and find that these peculiar types can be seen as extensions to the population of "normal" SNe Ia. With a larger number of objects, an updated fit to the Lira relation is presented along with evidence for a dependence on the late-time slope of the B-V color-curves with stretch and color. Using the full wavelength range from u to H band, we place constrai…
We present final natural system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type Ia SNe, 5 Type Iax SNe, 2 super-Chandrasekhar SN candidates, 2 Type Ia SNe interacting with circumstellar matter, and 2 SN 2006bt-like events. The redshifts of the objects range from z = 0.0037 to 0.0835; the median redshift is 0.0241. For 120 (90%) of these SNe, near-infrared photometry was obtained. Average optical e…
We present a new method to photometrically delineate between various sub-types of type Ia supernovae (SNe Ia). Using the color-stretch parameters, $s_{BV}$ or $s_{gr}$, and the time of i-band primary maximum relative to the B-band or g-band maximum it is demonstrated that 2003fg-like, 1991bg-like, and 2002cx-like SNe Ia can readily be identified. In the cases of these extreme SNe Ia, their primary i-band maximum occurs after the time of the B or g band maxima. We suggest that the timing of the i-band maximum can reveal the physical state of the SN Ia explosion as it traces: i) the speed of the…
The Type Ia supernova (SN Ia) LSQ14fmg exhibits exaggerated properties which may help to reveal the origin of the "super-Chandrasekhar" (or 03fg-like) group. The optical spectrum is typical of a 03fg-like SN Ia, but the light curves are unlike those of any SNe Ia observed. The light curves of LSQ14fmg rise extremely slowly. At -23 rest-frame days relative to B-band maximum, LSQ14fmg is already brighter than $M_V$=-19 mag before host extinction correction. The observed color curves show a flat evolution from the earliest observation to approximately one week after maximum. The near-infrared lig…
The Search for Stable Nickel: Investigating the Origins of Type Ia Supernovae with Late-time NIR Spectroscopy from the Carnegie Supernova Project-II
University of Virginia（弗吉尼亚大学）；Florida State University（佛罗里达州立大学）；University of Hawai’i（夏威夷大学）；Planetary Science Institute（行星科学研究所）；Hamburger Sternwarte（汉堡天文台）；Carnegie Observatories（卡内基观测站）；Purdue University（普渡大学）；Observatories of the Carnegie Institution for Science（卡内基科学研究所天文台）；Michigan State University（密歇根州立大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)（天体物理学跨学科探索与研究中心）；Institute of Space Sciences (ICE, CSIC)（空间科学研究所）；Institut d’Estudis Espacials de Catalunya (IEEC)（加泰罗尼亚空间研究研究所）；Aarhus University（奥胡斯大学）；American Public University System（美国公立大学系统）；Independent University, Bangladesh（孟加拉独立大学）；Rutgers, the State University of New Jersey（新泽西罗格斯大学）；Texas A&M University（德克萨斯农工大学）
Supernova LSQ13abf was discovered soon after explosion by the La Silla-QUEST Survey and followed by the CSP II at optical and near-IR wavelengths. Our analysis indicates LSQ13abf was discovered within two days of explosion and its first 10 days of evolution reveal a B-band light curve with an abrupt drop in luminosity. Contemporaneously, the V-band light curve exhibits a rise towards a first peak and the r- and i-band light curves show no early peak. The early light-curve evolution of LSQ13abf is reminiscent of the post explosion cooling phase observed in the Type Ib SN 2008D, and the similari…
In this Research Note we present a serendipitous discovery of the transient CGS2004A (AT2004iu) in an image collected by the Carnegie-Irvine Galaxy Survey of the Scd: galaxy NGC 1892, which we determine is most likely to have been a type IIP supernova.
We provide additional observational evidence that some Type Ia supernovae (SNe Ia) show signatures of circumstellar interaction (CSI) with hydrogen-rich material. Early phase optical and near-infrared (NIR) light curves and spectroscopy of SN 2008J obtained by the Carnegie Supernova Project are studied and compared to those of SNe 2002ic and 2005gj. Our NIR spectrum is the first obtained for a 2002ic-like object extending up to 2.2 $μ$m. A published high-resolution spectrum is used to provide insight on the circumstellar material (CSM). SN 2008J is found to be affected by $A_V\sim$ 1.9 mag of …
CfAIR2 is a large homogeneously reduced set of near-infrared (NIR) light curves for Type Ia supernovae (SN Ia) obtained with the 1.3m Peters Automated InfraRed Imaging TELescope (PAIRITEL). This data set includes 4607 measurements of 94 SN Ia and 4 additional SN Iax observed from 2005-2011 at the Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona. CfAIR2 includes JHKs photometric measurements for 88 normal and 6 spectroscopically peculiar SN Ia in the nearby universe, with a median redshift of z~0.021 for the normal SN Ia. CfAIR2 data span the range from -13 days to +127 days from B-b…
We construct the Type Ia supernovae (SNe Ia) luminosity function (LF) using the Zwicky Transient Facility Bright Transient Survey (BTS) catalogue. While this magnitude-limited survey has an unprecedented number of objects, it suffers from large distance uncertainties and lacks an estimation of host extinction. We bypass these issues by calculating the intrinsic luminosities from the shape parameters of the light curve's $ g $ and $ r $ bands, with the luminosities calibrated from the well observed SNe Ia sample of the Carnegie Supernova Project, allowing us to construct, for the first time, th…
We present an early-phase $g$-band light curve and visual-wavelength spectra of the normal Type Ia supernova (SN) 2013gy. The light curve is constructed by determining the appropriate S-corrections to transform KAIT natural-system $B$- and $V$-band photometry and Carnegie Supernova Project natural-system $g$-band photometry to the Pan-STARRS1 $g$-band natural photometric system. A Markov Chain Monte Carlo calculation provides a best-fit single power-law function to the first ten epochs of photometry described by an exponent of $2.16^{+0.06}_{-0.06}$ and a time of first light of MJD 56629.4$^{+…
In this paper, we present photometric and spectroscopic observations of a subluminous type Ia supernova (SN Ia) 2012ij, which has an absolute $B$-band peak magnitude $M_{B,\rm{max}}$ = $-$17.95 $\pm$ 0.15 mag. The $B$-band light curve exhibits a fast post-peak decline with $Δm_{15}(B)$ = 1.86 $\pm$ 0.05 mag. All the $R$ and $I$/$i$-band light curves show a weak secondary peak/shoulder feature at about 3 weeks after the peak, like some transitional subclass of SNe Ia, which could result from an incomplete merger of near-infrared (NIR) double peaks. The spectra are characterized by Ti~{\sc ii} a…
Supernova properties in radio strongly depend on their circumstellar environment and they are an important probe to investigate the mass loss of supernova progenitors. Recently, core-collapse supernova observations in radio have been assembled and the rise time and peak luminosity distribution of core-collapse supernovae at 8.4 GHz has been estimated. In this paper, we constrain the mass-loss prescriptions for red supergiants by using the rise time and peak luminosity distribution of Type II supernovae in radio. We take the de Jager and van Loon mass-loss rates for red supergiants, calculate t…
Mapping supernovae to their progenitors is fundamental to understanding the collapse of massive stars. We investigate the red supergiant problem, which concerns why red supergiants with masses $\sim16$-$30 M_\odot$ have not been identified as progenitors of Type IIP supernovae, and the supernova rate problem, which concerns why the observed cosmic supernova rate is smaller than the observed cosmic star formation rate. We find key physics to solving these in the compactness parameter, which characterizes the density structure of the progenitor. If massive stars with compactness above $ξ_{2.5} \…
The Swift Gamma Ray Burst Explorer has proven to be an incredible platform for studying the multiwavelength properties of supernova explosions. In its first ten years, Swift has observed over three hundred supernovae. The ultraviolet observations reveal a complex diversity of behavior across supernova types and classes. Even amongst the standard candle type Ia supernovae, ultraviolet observations reveal distinct groups. When the UVOT data is combined with higher redshift optical data, the relative populations of these groups appear to change with redshift. Among core-collapse supernovae, Swift…
