Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past ...B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission, and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for GRBs, we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of gamma-ray instruments.
We present an analysis of Type Ia Supernovae (SNe~Ia) from both the Carnegie
Supernova Project~I (CSP-I) and II (CSP-II), and extend the Hubble diagram from
the optical to the near-infrared ...wavelengths ($uBgVriYJH$). We calculate the
Hubble constant, $H_0$, using various distance calibrators: Cepheids, Tip of
the Red Giant Branch (TRGB), and Surface Brightness Fluctuations (SBF).
Combining all methods of calibrations, we derive $\rm H_0=71.76 \pm 0.58 \
(stat) \pm 1.19 \ (sys) \ km \ s^{-1} \ Mpc^{-1}$ from $B$-band, and $\rm
H_0=73.22 \pm 0.68 \ (stat) \pm 1.28 \ (sys) \ km \ s^{-1} \ Mpc^{-1}$ from
$H$-band. By assigning equal weight to the Cepheid, TRGB, and SBF calibrators,
we derive the systematic errors required for consistency in the first rung of
the distance ladder, resulting in a systematic error of $1.2\sim 1.3 \rm \ km \
s^{-1} \ Mpc^{-1}$ in $H_0$. As a result, relative to the statistics-only
uncertainty, the tension between the late-time $H_0$ we derive by combining the
various distance calibrators and the early-time $H_0$ from the Cosmic Microwave
Background is reduced. The highest precision in SN~Ia luminosity is found in
the $Y$ band ($0.12\pm0.01$ mag), as defined by the intrinsic scatter
($\sigma_{int}$). We revisit SN~Ia Hubble residual-host mass correlations and
recover previous results that these correlations do not change significantly
between the optical and the near-infrared wavelengths. Finally, SNe~Ia that
explode beyond 10 kpc from their host centers exhibit smaller dispersion in
their luminosity, confirming our earlier findings. Reduced effect of dust in
the outskirt of hosts may be responsible for this effect.
We present a detailed spectroscopic study of Herschel 36 A (H36A), the main stellar component of the massive multiple system Herschel 36 in the Hourglass Nebula, based on high-resolution optical ...spectra obtained along an 11 years span. The three stellar components present in the spectrum of H36A are separated by means of a spectral disentangling technique. Individual spectral classifications are improved, and high precision orbital solutions for the inner and the outer orbits are calculated. H36A is confirmed to be a hierarchical triple system composed of a close massive binary (Ab1+Ab2, O9.5 V+B0.7 V) in wide orbit around a third O-type star (Aa, O7.5 Vz). The inner-pair orbit is characterized by a period of 1.54157 +/- 0.00006 days, and semi-amplitudes of 181.2 +/- 0.7 and 295.4 +/- 1.7 km/s. The outer orbit has a period of 492.81 +/- 0.69 days, and semi-amplitudes of 62.0 +/- 0.6 and 42.4 +/- 0.8 km/s. Inner and outer orbits are not coplanar, having a relative inclination of at least 20 degrees. Dynamical minimum masses of 20.6 +/- 0.8 Msun, 18.7 +/- 1.1 Msun, and 11.5 +/- 1.1 Msun are derived for the Aa, Ab1, and Ab2 components, respectively, in reasonable agreement with the theoretical calibrations.
We present an analysis of Type Ia Supernovae (SNe~Ia) from both the Carnegie Supernova Project~I (CSP-I) and II (CSP-II), and extend the Hubble diagram from the optical to the near-infrared ...wavelengths (\(uBgVriYJH\)). We calculate the Hubble constant, \(H_0\), using various distance calibrators: Cepheids, Tip of the Red Giant Branch (TRGB), and Surface Brightness Fluctuations (SBF). Combining all methods of calibrations, we derive \(\rm H_0=71.76 \pm 0.58 \ (stat) \pm 1.19 \ (sys) \ km \ s^{-1} \ Mpc^{-1}\) from \(B\)-band, and \(\rm H_0=73.22 \pm 0.68 \ (stat) \pm 1.28 \ (sys) \ km \ s^{-1} \ Mpc^{-1}\) from \(H\)-band. By assigning equal weight to the Cepheid, TRGB, and SBF calibrators, we derive the systematic errors required for consistency in the first rung of the distance ladder, resulting in a systematic error of \(1.2\sim 1.3 \rm \ km \ s^{-1} \ Mpc^{-1}\) in \(H_0\). As a result, relative to the statistics-only uncertainty, the tension between the late-time \(H_0\) we derive by combining the various distance calibrators and the early-time \(H_0\) from the Cosmic Microwave Background is reduced. The highest precision in SN~Ia luminosity is found in the \(Y\) band (\(0.12\pm0.01\) mag), as defined by the intrinsic scatter (\(\sigma_{int}\)). We revisit SN~Ia Hubble residual-host mass correlations and recover previous results that these correlations do not change significantly between the optical and the near-infrared wavelengths. Finally, SNe~Ia that explode beyond 10 kpc from their host centers exhibit smaller dispersion in their luminosity, confirming our earlier findings. Reduced effect of dust in the outskirt of hosts may be responsible for this effect.
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, details of the
supernova sample, the observational strategy, and the characteristics of the
photometric data are provided. In a companion paper, the near-infrared
spectroscopy component of the project is presented.
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, details of the supernova sample, the observational strategy, and the characteristics of the photometric data are provided. In a companion paper, the near-infrared spectroscopy component of the project is presented.
We present an observational study of the Type IIn supernovae (SNe IIn) 2005ip and 2006jd. Broad-band UV, optical and near-IR photometry, and visual-wavelength spectroscopy of SN 2005ip complement and ...extend upon published observations to 6.5 years past discovery. Our observations of SN 2006jd extend from UV to mid-infrared wavelengths, and like SN 2005ip, are compared to reported X-ray measurements to understand the nature of the progenitor. Both objects display a number of similarities with the 1988Z-like subclass of SN IIn including: (i) remarkably similar early- and late-phase optical spectra, (ii) a variety of high ionization coronal lines, (iii) long-duration optical and near-IR emission and, (iv) evidence of cold and warm dust components. However, diversity is apparent including an unprecedented late-time r-band excess in SN 2006jd. The observed di erences are attributed to di erences between the mass-loss history of the progenitor stars. We conclude that the progenitor of SN 2006jd likely experienced a signi cant mass-loss event during its pre-SN evolution akin to the great 19th century eruption of eta Carinae. Contrarily, as advocated by Smith et al. (2009), we nd the circumstellar environment of SN 2005ip to be more consistent with a clumpy wind progenitor.
