On the nature of hydrogen-rich superluminous supernovae (Inserra+2018) Observational study of SLSNe with hydrogen, which are relavively rare compared to the Type Ic class. Some further evidence for the most common model involving CSI was presented.
"Long-duration superluminous supernovae at late times" (Jerkstrand+2017) A breakthrough in our understanding of superluminous SNe from two perspectives. 1) A strong similarity to GRB-SNe was revealed once galaxy contamination was recognized and carefully removed from both old a new data 2) Robustly inferred (largely model-independent) mass constraints on oxygen that points to very massive WR star progenitors. Combined with LIGO results last 2 years (black holes in mass range 15-40 exist and almost certainly imply failed SNe) we now seem faced to explain that massive WR stars sometimes make black holes but sometimes explode as SLSNe or GRB SNe.
The evolution of superluminous supernova LSQ14mo and its interacting host galaxy system (Chen+2017) Study of a Ic SLSN, where simultanous constraints from both the environment, light curve, and spectra were investigated.
Nebular spectra of pair-instability supernovae (Jerkstrand, Smartt & Heger 2016) An extensive model grid of pair instability SNe computed at 400-1000d after explosion, for M(He) = 70, 100 and 130 Msun progenitor helium cores. We compare the models with observations of SN 2007bi and PTF12dam, and find significant discrepancies. In particular do the models predicts red, line-blanked spectra rich in intermedite and heavy element lines. This is a large, qualitative discrepancy that we assess cannot be resolved by improved models, and therefore argue that PISNe are strongly disfavoured as the explanation for SLSNe.
Superluminous Supernova SN 2015bn in the Nebular Phase: Evidence for the Engine-powered Explosion of a Stripped Massive Star (Nicholl+2016) SN 2015bn was followed by two observational programmes, see also this paper for more data as well as in-depth modelling.
SN 2015bn: a detailed multi-wavelength view of a nearby super luminous supernova (Nicholl+2016) Extensive data-set on a long-duration SLSN, including only third late-time data set.
On the diversity of superluminous supernovae: ejected mass as the dominant factor (Nicholl, Smartt, Jerkstrand+, MNRAS 2015) Systematic study of parameter space in central engine and circumstellar interaction models. The point here was to attempt to derive some constraint by investigating the distribution of properties in a sample, e.g. if magnetars are behind SLSNe we would expect a certain distribution of light curve properties assuming a continuum of magnetar parameters. A model space of magnetar LCs fared quite well in this test, while CSI models would need some fine-tuning.
The host galaxy and late-time evolution of the Super-Luminous Supernova PTF12dam (Chen, Smartt, Jerkstrand+, MNRAS 2014) Late-time photometry of PTF12dam is modelled, we find here that for the magnetar model to reproduce the whole light curve, escape of high-energy radiation from the pulsar wind region must begin around 200 days. Only two studies of energy injection in fast-spin, high-B magnetars have been made, in one of these such radiation escape is obtained, in the other one less clearly so.
LSQ14bdq: A Type Ic Super-luminous Supernova with a Double-peaked Light Curve (Nicholl, Smartt, Jerkstrand+2015) Discovery of early cooling bump in light curve of a SLSN, which we know from studies of normal SNe can constrain other properties of the progenitor such as radius. Application of standard models here suggest large radii of several 100 Rsun, but this has no natural interpretation as a photosphere in a WR progenitor.
Superluminous supernovae from PESSTO (Nicholl, Smartt, Jerkstrand+, MNRAS 2014) Further light curve fits for three SLSNe from PESSTO. By looking at a bigger sample, it became clear that the "simple" magnetsar model does not always work, one needs to postulate leakage of hard radiation (which is perfectly viable within current uncertainties for these kind of pulsar wind nebulae, see e.g. this paper).
The superluminous supernova PS1-11ap: bridging the gap between low and high redshift (McCrum, Smartt, Kotak, Rest, Jerkstrand+, MNRAS 2012) Analysis of PS1-11ap including light curve fits.
Slowly fading super-luminous supernovae that are not pair-instability explosions (Nicholl, Smartt, Jerkstrand+, Nature 2013) In this paper the fast rise time of PTF12dam rules out an origin as a pair-instability SN, an important milestone in research on SLSNe. PTF12dam can be fit with a magnetar model, although other models may fit as well.
Super-luminous Type Ic Supernovae: Catching a Magnetar by the Tail (Inserra, Smartt, Jerkstrand+, ApJ 2013) Development of simple semi-analytical models to fit the light curves of SLSNe. The critical step here is to calibrate the generalised Arnett 1980/1982 method to the case where the ejecta are accelerating due to the late-time energy input. By comparing with simulations by Kasen and Bildsten, we found that the simple choice of using the mean of initial and final energy of the ejecta have extremely similar light curves. We used this formalism to fit 6 SLSNE Type Ic with magnetar-powered models; these fits are indeed satisfactory in term of both luminosity and photospheric velocity/temperature.