Type IIn supernovae (SNeIIn) are a highly heterogeneous subclass of core-collapse supernovae, spectroscopically characterized by signatures of interaction with a dense circumstellar medium (CSM). Here we systematically model the light curves of 142 archival SNeIIn using MOSFiT (the Modular Open Source Fitter for Transients). We find that the observed and inferred properties of SNIIn are diverse, but there are some trends. The typical SN CSM is dense ($\sim$10$^{-12}$gcm$^{-3}$) with highly diverse CSM geometry, with a median CSM mass of $\sim$1M$_\odot$. The ejecta are typically massive ($\gtrsim10$M$_\odot$), suggesting massive progenitor systems. We find positive correlations between the CSM mass and the rise and fall times of SNeIIn. Furthermore there are positive correlations between the rise time and fall times and the $r$-band luminosity. We estimate the mass-loss rates of our sample (where spectroscopy is available) and find a high median mass-loss rate of $\sim$10$^{-2}$M$_\odot$yr$^{-1}$, with a range between 10$^{-4}$--1M$_\odot$yr$^{-1}$. These mass-loss rates are most similar to the mass loss from great eruptions of luminous blue variables, consistent with the direct progenitor detections in the literature. We also discuss the role that binary interactions may play, concluding that at least some of our SNeIIn may be from massive binary systems. Finally, we estimate a detection rate of 1.6$\times$10$^5$yr$^{-1}$ in the upcoming Legacy Survey of Space and Time at the Vera C. Rubin Observatory.
Type IIn supernovae (SNe IIn) are a relatively infrequently observed subclass of SNe whose photometric and spectroscopic properties are varied. A common thread among SNe IIn are the complex multiple-component hydrogen Balmer lines. Owing to the heterogeneity of SNe IIn, online databases contain some outdated, erroneous, or even contradictory classifications. SN IIn classification is further complicated by SN impostors and contamination from underlying HII regions. We have compiled a catalogue of systematically classified nearby (redshift z < 0.02) SNe IIn using the Open Supernova Catalogue (OS…
Type IIn supernovae (SNe\,IIn) are an uncommon and highly heterogeneous class of SN where the SN ejecta interact with pre-existing circumstellar media (CSM). Previous studies have found a mass ladder in terms of the association of the SN location with H$α$ emission and the progenitor masses of SN classes. In this paper, we present the largest environmental study of SNe\,IIn. We analyse the H$α$ environments of 77 type IIn supernovae using continuum subtracted H$α$ images. We use the pixel statistics technique, normalised cumulative ranking (NCR), to associate SN pixels with H$α$ emission. We f…
Type IIn supernovae potentially constitute a large fraction of the gravitationally lensed supernovae predicted to be found with upcoming facilities. However, the local rate is used for these estimates, which is assumed to be independent of properties such as the host galaxy mass. Some studies hint that a host galaxy mass bias may exist for IIn supernovae. This paper aims to provide an updated local IIn supernova-to-core-collapse ratio based on data from the Palomar Transient Factory (PTF) and the Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS). Furthermore, the goal is to investi…
SN 2017hcc and SN 2023usc a comparative spectroscopic study of type IIn supernovae
Indian Institute of Astrophysics（印度天体物理研究所）；Instituto de Estudios Astrofísicos, Universidad Diego Portales（迭戈帕拉莱斯大学天体物理研究学院）；Millennium Institute of Astrophysics（天体物理千年研究所）；Department of Physics, Florida State University（佛罗里达州立大学物理系）；Homi Bhabha Center for Science Education Tata Institute of Fundamental Research（塔塔基础科学教育霍米巴巴中心）
Interacting supernovae (SNe) IIn and Ibn show narrow emission lines and have always been a mysterious and unsolved genre in SNe physics. We present a comprehensive analysis of the temporal and spectroscopic behaviour of a group of interacting SNe~IIn and Ibn. We choose SNe~2012ab, 2020cui, 2020rc and 2019uo as representative members of these SN sub-types to probe the nature of explosion. Our study reveals that SNe~IIn are heterogeneous, bright depicting multi-staged temporal evolution while SNe~Ibn are moreover homogeneous, comparatively fainter than SNe~IIn and short lived, but limited in sam…
We present a survey of the early evolution of 12 Type IIn supernovae (SNe IIn) in the Ultra-Violet (UV) and visible light. We use this survey to constrain the geometry of the circumstellar material (CSM) surrounding SN IIn explosions, which may shed light on their progenitor diversity. In order to distinguish between aspherical and spherical circumstellar material (CSM), we estimate the blackbody radius temporal evolution of the SNe IIn of our sample, following the method introduced by Soumagnac et al. We find that higher luminosity objects tend to show evidence for aspherical CSM. Depending o…
The impact of ultraviolet suppression on the rates and properties of strongly lensed Type IIn supernovae detected by LSST
School of Physics and Astronomy, University of Birmingham（伯明翰大学物理与天文学学院）；Department of Astrophysics, University of Vienna（维也纳大学天体物理学系）；Astrophysics Research Centre, School of Mathematics and Physics, Queen’s University Belfast（贝尔法斯特女王大学数学与物理学院天体物理学研究中心）；Oskar Klein Centre, Department of Physics, Stockholm University（斯德哥尔摩大学物理系奥萨尔·克莱因中心）；Institute of Cosmology and Gravitation, University of Portsmouth（朴茨茅斯大学宇宙学与引力研究所）
Observations suggest that some massive stars experience violent and eruptive mass loss associated with significant brightening that cannot be explained by hydrostatic stellar models. This event seemingly forms dense circumstellar matter (CSM). The mechanism of eruptive mass loss has not been fully explained. We focus on the fact that the timescale of nuclear burning gets shorter than the dynamical timescale of the envelope a few years before core collapse for some massive stars. To reveal the properties of the eruptive mass loss, we investigate its relation to the energy injection at the botto…
Fading Echoes of Interaction: Probing Centuries of Mass-Loss in Four Old Type IIn Supernovae
University of California, San Diego（加利福尼亚大学圣地亚哥分校）；University of Virginia（弗吉尼亚大学）；Indian Institute of Astrophysics（印度天体物理研究所）；University of California, Berkeley（加利福尼亚大学伯克利分校）
Transients powered by interaction with the circumstellar medium (CSM) are often observed in wavelengths other than optical, and multi-wavelength modelling can be important when inferring the properties of the explosion and CSM, or for distinguishing from other powering mechanisms. We develop a model calculating time dependent emission spectrum of interaction-powered transients. We solve energy equations of electron-proton plasma in the shocked SN ejecta and CSM and a radiation transfer equation out to the outer edge of the CSM, incorporating the collisional relaxation and the comptonization of…
Some massive stars experience episodic and intense mass loss phases with fluctuations in the luminosity. Ejected material forms circumstellar matter around the star, and the subsequent core collapse results in a Type IIn supernova that is characterized by interaction between supernova ejecta and circumstellar matter. The energy source that triggers these mass eruptions and dynamics of the outflow have not been clearly explained. Moreover, the mass eruption itself can alter the density structure of the envelope and affect the dynamics of the subsequent mass eruption if these events are repeated…
The physical characteristics of dust formed in supernovae is poorly known. In this paper, we investigate the extinction properties of dust formed in the type IIn SN 2005ip. The observed light curves of SN 2005ip all exhibit a sudden drop around 50 days after discovery. This has been attributed to dust formation in the dense circumstellar medium. We modeled the intrinsic light curves in six optical bands, adopting a theoretical model for the luminosity evolution of supernovae interacting with their circumstellar material. From the difference between the observed and intrinsic light curves, we c…
Young core-collapse supernovae (YSNe) are factories of high-energy neutrinos and gamma-rays as the shock accelerated protons efficiently interact with the protons in the dense circumstellar medium. We explore the detection prospects of secondary particles from YSNe of Type IIn, II-P, IIb/II-L, and Ib/c. Type IIn YSNe are found to produce the largest flux of neutrinos and gamma-rays, followed by II-P YSNe. Fermi-LAT and the Cherenkov Telescope Array (IceCube-Gen2) have the potential to detect Type IIn YSNe up to $10$~Mpc ($4$~Mpc), with the remaining YSNe Types being detectable closer to Earth.…
We present observations of the rise and peak of the Type IIn supernova SN 2017hcc/ATLAS17lsn obtained by the All-Sky Automated Survey for Supernovae (ASAS-SN) and Swift UVOT. The light curve of SN 2017hcc/ATLAS17lsn peaks at $V\simeq 13.7$ mag, which from the estimated redshift of the host galaxy ($z=0.0168$, $D\simeq 73$ Mpc) implies an absolute peak magnitude $M_{V,peak} \simeq -20.7$ mag. The near-UV to optical spectral energy distribution of SN 2017hcc/ATLAS17lsn from Swift UVOT is consistent with a hot, but cooling blackbody with $\rm T_{bb}\simeq 16500$ K on Oct. 28.4 and $\rm T_{bb} \si…
We present a sample of supernovae Type IIn (SNe IIn) from the untargeted, magnitude-limited surveys of the Palomar Transient Factory (PTF) and its successor, the intermediate PTF (iPTF). The SNe IIn found and followed by the PTF/iPTF were used to select a sample of 42 events with useful constraints on the rise times as well as with available post-peak photometry. The sample SNe were discovered in 2009-2016 and have at least one low-resolution classification spectrum, as well as photometry from the P48 and P60 telescopes at Palomar Observatory. We study the light-curve properties of these SNe I…
SN 2024dy: Dust formation in a long-lived Type IIn supernova and constraints on the dust mass
Kagoshima University（鹿儿岛大学）；Hiroshima University（广岛大学）；Tohoku University（东北大学）；Stockholm University（斯德哥尔摩大学）；Indian Institute of Astrophysics（印度天体物理研究所）
Some supernovae such as pair-instability supernovae are predicted to have the duration of more than a year in the observer frame. To constrain the rates of supernovae lasting for more than a year, we conducted a long-term deep transient survey using Hyper Suprime-Cam (HSC) on the 8.2m Subaru telescope. HSC is a wide-field (a 1.75 deg2 field-of-view) camera and it can efficiently conduct transient surveys. We observed the same 1.75 deg2 field repeatedly using the g, r, i, and z band filters with the typical depth of 26 mag for 4 seasons (from late 2016 to early 2020). Using these data, we searc…
All Type IIn supernovae (SNe IIn) show narrow hydrogen emission lines in their spectra. Apart from this common feature, they demonstrate very broad diversity in brightness, duration, and morphology of their light curves, which indicates that they likely come from a variety of progenitor systems and explosion channels. A particular subset of SNe IIn, the so called SNe IIn-P, exhibit $\sim$100 days plateau phases that are very similar to the ones of the ordinary hydrogen-rich SNe (SNe II). In the past, SNe IIn-P were explained by the models of sub-energetic electron capture explosions surrounded…
Stripped-envelope core-collapse supernovae can be divided into two broad classes: the common Type Ib/c supernovae (SNe Ib/c), powered by the radioactive decay of $^{56}$Ni, and the rare superluminous supernovae (SLSNe), most likely powered by the spin-down of a magnetar central engine. Up to now, the intermediate regime between these two populations has remained mostly unexplored. Here, we present a comprehensive study of 40 \textit{luminous supernovae} (LSNe), SNe with peak magnitudes of $M_r = -19$ to $-20$ mag, bound by SLSNe on the bright end and by SNe Ib/c on the dim end. Spectroscopical…
We present the public release of the Complete History of Interaction-Powered Supernovae (CHIPS) code, suited to model a variety of transients that arise from interaction with a dense circumstellar medium (CSM). Contrary to existing modellings which mostly attach the CSM by hand, CHIPS self-consistently simulates both the creation of the CSM from mass eruption of massive stars prior to core-collapse, and the subsequent supernova light curve. We demonstrate the performance of CHIPS by presenting examples of the density profiles of the CSM and the light curves. We show that the gross light curve …
We assemble a large set of 2-10 GHz radio flux density measurements and upper limits of 294 different supernovae (SNe), from the literature and our own and archival data. Only 31% of the SNe were detected. We characterize the SN lightcurves near the peak using a two-parameter model, with $t_{\rm pk}$ being the time to rise to a peak and $L_{\rm pk}$ the spectral luminosity at that peak. Over all SNe in our sample at $D<100$ Mpc, we find that $t_{\rm pk} = 10^{1.7\pm0.9}$ d, and that $L_{\rm pk} = 10^{25.5\pm1.6}$ erg s$^{-1}$ Hz$^{-1}$, and therefore that generally, 50% of SNe will have $L_{\r…
This work utilizes established models of synchrotron-powered light curves for core-collapse supernovae in dense circumstellar environments, namely type IIn and Ibn, to demonstrate the potential for detecting millimeter emission from these events. The progenitor types of these supernovae are still an open question, but using the synchrotron light curves as probes for the circumstellar environments could shed light on the mass-loss histories of the progenitors and discern between different theories. Observations in millimeter bands are particularly fruitful, as they probe regions at smaller radi…
Interaction-powered supernovae (SNe) explode within an optically-thick circumstellar medium (CSM) that could be ejected during eruptive events. To identify and characterize such pre-explosion outbursts we produce forced-photometry light curves for 196 interacting SNe, mostly of Type IIn, detected by the Zwicky Transient Facility between early 2018 and June 2020. Extensive tests demonstrate that we only expect a few false detections among the 70,000 analyzed pre-explosion images after applying quality cuts and bias corrections. We detect precursor eruptions prior to 18 Type IIn SNe and prior to…
Revealing the diversity of Type IIn supernova progenitors through their environments
School of Astronomy and Space Science, University of Chinese Academy of Sciences（中国科学院大学天文与空间科学学院）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（北京师范大学天文与空间前沿研究院）；Institute of Astrophysics, Foundation for Research and Technology-Hellas（希腊基础研究与技术基金会天体物理研究所）；Physics Department, National and Kapodistrian University of Athens（雅典国立卡波蒂斯坦大学物理系）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；Department of Physics, Royal Holloway, University of London（伦敦大学皇家霍洛威学院物理系）
