We have obtained 1087 NIR (JHKs) measurements of 21 SNe Ia using PAIRITEL, nearly doubling the number of well-sampled NIR SN Ia light curves. These data strengthen the evidence that SNe Ia are excellent standard candles in the NIR, even without correction for optical light-curve shape. We construct fiducial NIR ...

The properties of underluminous Type Ia supernovae (SNe Ia) of the 91bg subclass have yet to be theoretically understood. Here, we take a closer look at the structure of the dim SN Ia 2005bl. We infer the abundance and density profiles needed to reproduce the observed ...

Spectroscopic analyses of Type Ia supernovae have shown that there exist four spectroscopic groups-cool, broad line, shallow silicon, and core normal-defined by the widths of the Si II features ?5972 and ?6355. The 1991bg-like SNe Ia are classified as "cool." Cool SNe Ia are dim, undergo a rapid decline in ...

Context. The origin of subluminous Type Ia supernovae (SNe Ia) has long eluded any explanation, because all Chandrasekhar-mass models have severe problems reproducing them. Recently, it has been proposed that violent mergers of two white dwarfs of 0.9 M&sun; could lead to subluminous SNe Ia events that resemble 1991bg-like SNe ...

While SN 1991bg is an unusual type Ia SN in such a feature as the brief duration of the photospheric

weak 3-d deflagration? " high mass and density at low velocity: failed SN Ia? " peculiar objects may be the key to understanding normal SN Ia! Jha et al. ...

The Canada-France-Hawaii Telescope Supernova Legacy Survey (CFHT SNLS) has created a large homogeneous database of intermediate redshift (0.2 < z < 1.0) type Ia supernovae (SNe Ia). The SNLS team has shown that correlations exist between SN Ia rates, properties, and host galaxy star-formation rates (SFRs). ...

Type Ia Supernova (SN Ia) are a powerful, albeit not completely understood, tool for cosmology. Gaps in our understanding of their progenitors and detailed physics can lead to systematic errors in the cosmological distances they measure. We use UV data in two context to help further our understanding of SN ...

Optical photometry for 185 Supernovae Type Ia (SN Ia) from the F. L. Whipple Observatory is presented, more than doubling the nearby sample. Over 11500 CCD observations were acquired during the years 2001-2008. Our photometry is internally consistent and agrees to a few hundredths mag with that of other groups in cases where the same ...

We analyze the influence of the evolution of light absorption by gray dust in the host galaxies of type Ia supernovae (SN Ia) and the evolution of the mean combined mass of close-binary carbon-oxygen white dwarfs merging due to gravitational waves (SN Ia precursors) on the interpretation of ...

We observed SN 2011fe, a probable Type Ia SN in M101, with the EVLA on 25.8 Aug 2011 UT. Our observations yielded a non-detection of -5 ± 6 microJy at the SN position (ATel #3581). While no radio emission has ever been detected from a SN Ia, the majority of all ...

Modeling the X-ray emission from Tycho SNR. SN Ia explosion models. Testing SN Ia models. Explosion model. ?. HydroCode ...

Multiple outbursts of type Ia SNe in one galaxy present a unique opportunity to study the homogeneity of these objects. NGC 3147 is only the second known galaxy with three SNe Ia, another one is NGC 1316. We present CCD UBVRI photometry for SN Ia 2008fv and compare the light and color curves of this object to those ...

The validity of carbon-deflagration models white dwarf models for type Ia supernovae is investigated

of SNe Ia from a complete sample to help with the rate calculations, and the correlations between SN rates and their host galaxy properties. We find that there is a...

We present an analysis of supernova (SN) light curves simulated for the upcoming Dark Energy Survey (DES). We employed a code suite (SNANA) that generates and fits realistic SN light curves. We forecast that the DES sample of well measured Type Ia supernovae (SNe Ia) will number from 2300 to 3000 or more out to a ...

We used 3 years of SuperNova Legacy Survey (SNLS) data to constraint the SN Ia progenitor scenarios. We searched for an excess in the early portion of SNLS lightcurves, signature of shocking by a companion, as predicted in Kasen 2010. We find no evidence of such excess and we are able to constrain the contribution of single degenerate systems with a Red ...

The host galaxy environments of type Ia supernovae (SNe Ia) provide our best opportunity for constraining the mechanism(s) of the SN Ia progenitor system, i.e., the stars involved, the incubation times, and the sensitivity of SNe Ia to changes in the local gas-phase metallicity. The latter can ...

Recent analyses of the rise-times of Type Ia supernovae (SNe Ia) have suggested that there may exist two distinct populations of SNe Ia. In order to help resolve the controversy, we use the Schwarz Information Criterion (SIC) to quantify the belief that SN Ia rise-times are best described by a ...

We present a measurement of the rate of high-z Type Ia supernovae (SNe Ia) using multi-epoch observations of Subaru/XMM-Newton Deep Field (SXDF) with Suprime-Cam on the Subaru Telescope. Although SNe Ia are regarded as a standard candle, progenitor systems of SNe Ia have not been resolved yet. One of the key ...

The Type Ia supernova science working group of the Palomar Transient Factory (ATEL#1964) reports the discovery of the Type Ia supernova PTF10mwb. A spectrum of PTF10mwb was taken on Gemini North on June 30 UT. The redshift is approximately z=0.03 ± 0.01, from a fit to the SN. Matches to other spectra using Superfit (Howell et al. ...

Physical models of Type Ia supernovae (SN Ia) that do not depend on secondary calibrators have indicated that the Hubble Constant must be about 65 km/s/Mpc for well over a decade with the range of uncertainty shrinking with the sophistication of the models. This estimate is in good agreement with those based on HST observations of ...

The observations of Type Ia supernovae (SN Ia), Baryon Acoustic Oscillations (BAO) and Cosmic Microwave Background radiation (CMB) provide powerful tools for the measurement of cosmological parameters. One of the most useful information encodes in the distance measured by those probes. In this Letter, we test the coherence of the ...

The nature of Type Ia supernova (SN Ia) explosions has not yet been clarified, despite their importance in astrophysics and cosmology. Recent theoretical investigations suggest that asymmetric distribution of initial thermonuclear sparks may be a key in the SN Ia explosion mechanism. In this ...

We present measurements of the Type Ia supernova rate in both high-redshift galaxy clusters and the field. For the first time, we detect a significant increase in the cluster rate with redshift, when compared to lower-redshift measurements. Our field rate measurement indicates an SN Ia rate that is flat or decreasing with redshift at z ...

For my Astronomy Ph.D. thesis at Harvard University, I used the PAIRITEL 1.3m robotic telescope at the Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona to observe Near-Infrared (NIR) JHKs band light curves of over 100 Type Ia Supernovae (SN Ia) in nearby galaxies, compiling a data set that will more than quintuple the number ...

We performed the Southern inTermediate Redshift ESO Supernova Search (STRESS), a survey specifically designed to measure the rate of both SNe Ia and CC SNe, in order to obtain a direct comparison of the high redshift and local rates and to investigate the dependence of the rates on specific galaxy properties, most notably their colour. We found that the type ...

Type Ia Supernovae (SNe Ia) have high and homogeneous luminosities, making them an essential tool for measuring distances on a cosmic scale, useful to gauge the geometry and evolution of the Universe. However, the nature of the progenitor system of these explosions is still uncertain. The consensus view is that SNe Ia originate from an ...

SN 2006bt displays characteristics unlike those of any other known Type Ia supernova (SN Ia). We present optical light curves and spectra of SN 2006bt which demonstrate the peculiar nature of this object. SN 2006bt has broad, slowly declining light curves indicative of a ...

The Dark Energy Survey (DES) will conduct a dedicated Supernova Survey to discover and obtain multi-band light curves of Type Ia supernovae over a broad redshift range of 0.1 < z < 1. We describe our hybrid survey strategy that targets both high-redshift SN Ia for improved constraints on dark energy, as well as ...

Type Ia Supernova (SN Ia) are a powerful, albeit not completely understood, tool for cosmology. Gaps in our understanding of their progenitors and detailed physics can lead to systematic errors in the cosmological distances they measure. We use UV data in two context to help further our understanding of SN ...

M. Phillips publishes paper on using SN Ia as standard candles (1993); Hulse and Taylor win Nobel prize for binary pulsar (another confirmation of GR) (1993 ...

Feb 13, 2008 ... The new method they used provides great future promise for ... The supernova, known as SN 2007on, was identified as a Type Ia supernova. ...

users only when distances are based on Type Ia Supernova (SNIa), Type II Supernova optical (SNII optical), or Type II Supernova radio (SNII radio) methods, stating which SN...

We present a measurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z <~ 0.3, of which 270(52%) are spectroscopically identified as SNe ...

We argue here that models of SN Ia based on gravitational collapse with the ejection of only a small amount of matter and nickel will be subluminous, and are likely to have problems with the light curve and especially with the spectral evolution. Canonical thermonuclear explosion models can account for the light curves not only in the optical but in the IR ...

The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here, we use a new observational technique to measure this time delay by comparing the spatial distributions of SNe Ia ...

The type Ia supernova (SN Ia) rate in galaxy clusters can be a powerful probe of both the SN Ia progenitor system and the intracluster medium of the clusters themselves. The cluster SN Ia rate has recently been measured at redshifts below 0.2, but only ...

We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe ...

We present a new dataset of low-redshift nearby-Hubble-flow Type Ia supernova (SN Ia), a new compilation of the world's SN Ia datasets and new analysis procedures to work with these heterogeneous compilations. This ``Union'' compilation of nearly 400 SN ...

SNLS1 � SN Ia Hubble Diagram M = 0.263 � 0.042 (stat) � 0.032 (sys) =-1.02 � 0.09 (stat) � 0.054 (sysThe Supernova Legacy Survey:The Supernova Legacy Survey: Dark Energy and SNe IaDark Energy and SNe Ia Mark SullivanMark Sullivan University of OxfordUniversity of Oxford http

The largely unknown type Ia supernova mechanism remains one of the largest sources of possible systematic uncertainty in achieving precise measures of dark energy. The host galaxy environments of SNe Ia provide our best opportunity for constraining the mechanism(s) of the SN Ia progenitor system, i.e., the stars ...

We present multi-band photometry and multi-epoch spectroscopy of the peculiar Type Ia supernova (SN Ia) 2007qd, discovered by the SDSS-II Supernova Survey. It possesses physical properties intermediate to those of the peculiar SN 2002cx and the extremely low-luminosity SN 2008ha. Optical ...

Brighter Type Ia supernovae (SNe Ia) have broader, more slowly declining B-band light curves than dimmer SNe Ia. We study the physical origin of this width-luminosity relation (WLR) using detailed radiative transfer calculations of Chandrasekhar-mass SN Ia models. We find that the luminosity ...

With the advent of large dedicated Type Ia supernova (SN Ia) surveys, K-corrections of SNe Ia and their uncertainties have become especially important in the determination of cosmological parameters. While K-corrections are largely driven by SN Ia broadband colors, it is ...

Using light curves and host galaxy spectra of 101 Type Ia supernovae (SNe Ia) with redshift z {approx}< 0.3 from the Sloan Digital Sky Survey Supernova Survey (SDSS-SN), we derive the SN Ia rate as a function of progenitor age (the delay time distribution, DTD). We use the VESPA stellar ...

I have constructed a comprehensive statistical model for Type Ia supernova light curves spanning optical through near infrared data simultaneously. The near infrared light curves are found to be excellent standard candles (sigma(MH) = 0.11 +/- 0.03 mag) that are less vulnerable to systematic error from dust extinction, a major confounding factor for cosmological studies. A ...

Type Ia supernovae (SNe Ia) are excellent tools in cosmology. Their intrinsic luminosities are found to vary systematically with the light-curve widths, providing an empirical calibration. This property, called the width-luminosity relation (WLR), is the basis of modern SN Ia cosmology and led to the unexpected ...

We analyse the behaviour of the stellar winds of evolved stars and the outcome of Type Ia supernova (SN) explosions in a relativistic bubble driven by active galactic nuclei (AGNs). We find that the expansion of wind shells is efficiently decelerated by the relativistic pressure; however, their bulk motion is preserved, so they cross the bubble together ...

Because Type Ia supernovae (SNe Ia) are not perfect standard candles, it is important to be able to use distance--independent observables (DIOs) to define subsets of SNe Ia that are "nearly standard candles" or to correct SN Ia absolute magnitudes to make them nearly homogeneous ("standardized ...

We present an analysis of the host galaxy dependencies of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe ...

We present an analysis of the host galaxy dependences of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe ...

We present an analysis of the host galaxy dependences of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe ...

We show that when a procedure is made to remove the tension between a supernova Ia (SN Ia) data set and observations from BAO and CMB, there might be the case where the same SN Ia set built with two different light-curve fitters behaves as two separate and distinct supernova sets, and the ...

This evaluation for A = 113 updates one by J. Blachot, (2005Bl05), published in Nuclear Data Sheets 104, 791 (2005)

The author presents new measurements of the type Ia SN rate from the SDSS-II Supernova Survey. The SDSS-II Supernova Survey was carried out during the Fall months (Sept.-Nov.) of 2005-2007 and discovered {approx} 500 spectroscopically confirmed SNe Ia with densely sampled (once every {approx} 4 days), multi-color light curves. ...

UBVRI photometry and medium-resolution optical spectroscopy of the peculiar Type Ia supernova SN 2005hk are presented and analyzed, covering the premaximum phase to around 400 days after explosion. The supernova is found to be underluminous compared to ``normal'' Type Ia supernovae. The photometric and spectroscopic evolution of ...

We present Keck optical spectra of SN 2002cx, the most peculiar known Type Ia supernova (SN Ia), taken 227 and 277 days past maximum light. Astonishingly, the spectra are not dominated by the forbidden emission lines of iron that are a hallmark of thermonuclear SNe in the nebular phase. Instead, we identify ...

Aims: We present the first theoretical SN Ia light curves calculated with the time-dependent version of the general purpose model atmosphere code PHOENIX. Our goal is to produce light curves and spectra of hydro models of all types of supernovae. Methods: We extend our model atmosphere code PHOENIX to calculate type Ia supernovae ...

We still lack knowledge about the origin of thermonuclear supernovae (SN Ia) despite their huge cosmological and galactochemical importance. It seems likely that the evolution leading up to the SN Ia explosion involves mass transfer from a companion star onto the progenitor white dwarf. Detecting the wind from a ...

The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN Ia) generates a kinetic energy comparable to that released by a massive star during a SN II event. Current observations and theoretical models have established that SNe Ia are asymmetric, and therefore--like SNe ...

The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN Ia) generates a kinetic energy comparable to that released by a massive star during a SN II event. Current observations and theoretical models have established that SNe Ia are asymmetric, and therefore�like SNe ...

SN 2009ku, discovered by Pan-STARRS-1, is a Type Ia supernova (SN Ia), and a member of the distinct SN 2002cx-like class of SNe Ia. Its light curves are similar to the prototypical SN 2002cx, but are slightly broader and have a later rise to maximum in ...

We analyse behavior of stellar winds of evolved stars and the outcome of SN Ia explosions in the AGN driven relativistic bubble. We find that the expansion of wind shells is efficiently decelerated by the relativistic pressure; their bulk motion however is preserved so they cross the bubble together with the parent star. The wind material occupies a small ...

Analysis of spatially resolved ASCA spectra of the intracluster gas in Abell 496 confirms there are mild metal abundance enhancements near the center, as previously found in a joint analysis of spectra from Ginga Large Area Counter and Einstein solid state spectrometer. Simultaneous analysis of spectra from all ASCA instruments (SIS+GIS) shows that the iron abundance is 0.36+/-0.03 solar 3'-12' ...

We propose to continue our calibration experiment for M{max} of type Ia supernovae {SNe Ia} by determining Cepheid distances to their parent galaxies. To date we have completed the calibration for 6 SNe Ia, from Cycles 1, and 3 - 5. The results for 5 SNe Ia have been published in extenso. A letter on the sixth ...

We present an updated version of the Multicolor Light Curve Shape method to measure distances to type Ia supernovae (SN Ia), incorporating new procedures for K-correction and extinction corrections. We also develop a simple model to disentangle intrinsic color variations and reddening by dust, and expand the method to incorporate ...

It is still not clear what the progenitors of Type Ia Supernovae (SN Ia) are. There are currently two major competing (or compatible) formation channels under consideration: the single-degenerate scenario and the double-degenerate scenario (DDS). A DDS SN Ia is the result of the merger of two ...

Sentinel node (SN) identification in patients with lung cancer is useful not only to minimize lymph node dissection, but also to target the best lymph nodes for intraoperative frozen section during segmentectomy. Since 2000, we have identified the SN in lung cancer patients using radioisotope (RI). This review presents our data on SN ...

We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11,500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains the largest number of homogeneously observed and reduced nearby SNe Ia (z lsim 0.08) ...

We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11,500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains the largest number of homogeneously observed and reduced nearby SNe Ia (z ...

We present a new method to standardize type Ia supernova (SN Ia) luminosities to ?0.13 mag using flux ratios from a single flux-calibrated spectrum per SN. Using Nearby Supernova Factory spectrophotomery of 58 SNe Ia, we performed an unbiased search for flux ratios that correlate with ...

We report that the recently discovered type Ia SN PTF11kly in M101 (ATEL #3581) is at a projected galactocentric distance that corresponds to an oxygen abundance of 12+log(O/H) = 8.45 ± 0.05, according to the M101 gas-phase oxygen abundance gradient of Bresolin et al. (2007,ApJ,656,186), assuming that the SN is in the plane of the ...

In this paper, we present and analyse optical photometry and spectra of the extremely luminous and slowly evolving Type Ia supernova (SN Ia) 2009dc, and offer evidence that it is a super-Chandrasekhar mass (SC) SN Ia and thus has a SC white dwarf (WD) progenitor. Optical spectra of ...

We analyze the three-year Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey data and identify a sample of 1070 photometric Type Ia supernova (SN Ia) candidates based on their multiband light curve data. This sample consists of SN candidates with no spectroscopic confirmation, with a ...

Type Ia supernovae (SNe Ia) are good cosmological distance indicators due to their high luminosities and remarkable uniformity, and thus are used for determining cosmological parameters. However, several key issues related to the nature of their progenitor systems are still not well understood. In this thesis, the progenitors of SNe Ia ...

We computed optical and infrared light curves of the pulsating class of delayed detonation models for Type Ia supernovae (SNe Ia). It is demonstrated that observations of the IR light curves can be used to identify subluminous SNe Ia by testing whether secondary maxima occur in the IR. Our pulsating delayed detonation models are in ...

The light curve of SN 1572 is described in the terms used nowadays to characterize Type Ia supernovae (SNe Ia). By assembling the records of the observations done in 1572-1574 and evaluating their uncertainties, it is possible to recover the light curve and the color evolution of this supernova. It is found that within the ...

We present a comprehensive statistical analysis of the properties of Type Ia supernova (SN Ia) light curves in the near-infrared using recent data from Peters Automated InfraRed Imaging TELescope and the literature. We construct a hierarchical Bayesian framework, incorporating several uncertainties including photometric error, peculiar ...

Type Ia Supernovae(SNe Ia) have large and very homogeneous luminosities, making them an important tool for measuring distances on a cosmic scale, helping to study the evolution of the Universe. However, the nature of the progenitor system of these explosions is still uncertain. The consensus view is that SNe Ia originate from a close ...

Our lack of understanding of Type Ia supernova {SN Ia} explosions limits our confidence in their use for cosmology. While there is broad agreement that these objects represent the explosions of white dwarfs, the details of the explosion mechanism are not well-understood. Recently, we have identified an internally homogeneous subclass ...

Aims:To measure the supernova (SN) rates at intermediate redshift we performed a search, the Southern inTermediate Redshift ESO Supernova Search (STRESS). Unlike most of the current high redshift SN searches, this survey was specifically designed to estimate the rate for both type Ia and core collapse (CC) SNe. Methods: We counted the ...

The Palomar Transient Factory (PTF) is an astronomical wide-field survey designed to search for optical transient and variable sources. PTF began on-sky operations in early 2009. It is fully-automated, including a wide-field survey camera, an automated real-time data reduction pipeline and transient classifier, a dedicated photometric follow up telescope, and a full archive of all detected ...

High-quality observations of B and V light curves obtained at Las Campanas Observatory for local Type Ia Supernovae (SNe Ia) show clear evidence that SNe Ia with the same brightness decline or stretch may have systematic and independent deviations at times t {approx}< 5 days before and at times t {approx}> 30 days after ...

Increasingly large photometric surveys of transient phenomena, such as Pan-STARRS, DES and LSST, will locate thousands to millions of SNe Ia candidates per year, a rate prohibitive for acquiring spectroscopy to determine each candidate's type and redshift. Multiple supernova photometric classification/photo-z algorithms have been developed in recent years to deal with the ...

We combine the CfA3 supernovae Type Ia (SN Ia) sample with samples from the literature to calculate improved constraints on the dark energy equation of state parameter, w. The CfA3 sample is added to the Union set of Kowalski et al. to form the Constitution set and, combined with a BAO prior, produces 1 + w = 0.013{sup +0.066} {sub ...

SN 1006 is one of the supernova remnants (SNR) recorded in the Japanese diary 'Meigetsuki'. From the historical records including Meigetsuki, we conclude that SN 1006 was the brightest type Ia supernova remnant. We report on the observations of SN 1006 with the X-ray Imaging Spectrometers (XIS) on ...

We use models of the rates of Type Ia supernovae (SNe Ia) and core-collapsed supernovae, built in such a way that both are consistent with recent observational constraints at z<~ 1.6 and can reproduce the measured cosmic star formation rate, to recover the history of metal accumulation in the intracluster medium. We show that these ...

The element abundance distributions in the ejecta of Type Ia supernova (SN) is studied by modelling a time series of optical spectra of SN 2003du until �1 yr after the explosion. Since SN 2003du is a very normal Type Ia SN both photometrically and spectroscopically, the ...

In recent years, type Ia supernovae (SNe Ia) have been used successfully as cosmological probes of the Universe. However, the nature of their progenitors has remained somewhat of a mystery. It is widely accepted that they represent the disruption of a degenerate object, but there are also numerous progenitor models, but most of these have serious ...

The historical supernova remnant (SNR) Tycho SN 1572 originates from the explosion of a normal Type Ia supernova that is believed to have originated from a carbon-oxygen white dwarf in a binary system. We analyze the 21 cm continuum, H I, and 12CO-line data from the Canadian Galactic Plane Survey in the direction of SN 1572 and the ...

We present early-time optical and near-infrared photometry of supernova (SN) 2005cf. The observations, spanning a period from about 12 d before to 3 months after maximum, have been obtained through the coordination of observational efforts of various nodes of the European Supernova Collaboration and including data obtained at the 2-m Himalayan Chandra Telescope. From the ...

UBVRIJ photometry and optical spectra of the type Ia SN 1996X obtained at the European Southern Observatory (ESO) during a 1-yr-long observational campaign are presented, and supplemented by late-time Hubble Space Telescope (HST) photometry. Spectroscopically, SN 1996X appears to be a `normal' SN ...

We present a measurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z {approx}< 0.3, of which 270 (52%) are spectroscopically identified as SNe ...

Context. The SDSS-II Supernova Survey, conducted between 2005 and 2007, was designed to detect a large number of Type Ia supernovae (SNe Ia) around z~0.2, the redshift �gap� between low-z and high-z SN searches. The survey has provided multi-band photometric lightcurves for variable targets, and SN candidates ...

The Type Ia supernova (SN Ia) rate, when compared to the cosmic star formation history (SFH), can be used to derive the delay-time distribution (DTD; the hypothetical SN Ia rate versus time following a brief burst of star formation) of SNe Ia, which can distinguish among ...

We present STRESS (Southern intermediate redshift ESO Supernova Search) a Supernova (SN) survey successfully carried out with ESO telescopes. This SN survey distinguishes itself by other ones for its main goals that are to obtain an estimate of both type Ia and core collapse SN rate and to link them with stellar ...

Context. Based on the single degenerate (SD) scenario, a super-Chandrasekhar mass model derived from the rapid rotation of a progenitor star may account for the overluminous type Ia supernovae (SNe Ia) like SN 2003fg. Previous authors calculated a series of binary evolution and showed the parameter spaces for the super-Chandrasekhar ...

Using data from the Sloan Digital Sky Supernova Survey-II, we measure the rate of Type Ia Supernovae (SNe Ia) as a function of galaxy properties at intermediate redshift. A sample of 342 SNe Ia with 0.05<0.25 is constructed. Using broad-band photometry we use the PEGASE spectral energy distributions (SEDs) to estimate host ...

Large samples of high-redshift supernovae (SNe) are potentially powerful probes of cosmic star formation, metal enrichment and SN physics. We present initial results from a new deep SN survey, based on re-imaging in the R,i', z' bands, of the 0.25deg2 Subaru Deep Field (SDF), with the 8.2-m Subaru telescope and Suprime-Cam. In a single new epoch consisting ...

Type Ia supernovae (SNe Ia) have been very successful tools for studying the history of cosmic expansion and led to the discovery of the accelerating universe and dark energy. However, the explosion mechanism and progenitors for SNe Ia are still not fundamentally well understood. We present results from late time (up to 600 days past ...

We present extensive u{prime}g{prime}r{prime}i{prime} BV RIY JHK{sub s} photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been called 'the most peculiar known type Ia supernova'. Both ...

We discuss the expansion velocities of different elements in the ejecta of the intermediate--z Type Ia supernovae (SNe Ia) discovered as a part of the International Time Programme (ITP) project ``? and ? from Supernovae and the Physics of Supernovae Explosions'' at the European Northern Observatory (ENO). The expansion velocities measured for each normal ...

We use multi-wavelength, matched aperture, integrated photometry from the Galaxy Evolution Explorer (GALEX), the Sloan Digital Sky Survey, and the RC3 to estimate the physical properties of 166 nearby galaxies hosting 168 well-observed Type Ia supernovae (SNe Ia). The ultraviolet (UV) imaging of local SN Ia hosts ...

We use multi-wavelength, matched aperture, integrated photometry from the Galaxy Evolution Explorer (GALEX), the Sloan Digital Sky Survey, and the RC3 to estimate the physical properties of 166 nearby galaxies hosting 168 well-observed Type Ia supernovae (SNe Ia). The ultraviolet (UV) imaging of local SN Ia hosts ...

Using data drawn from the Sloan Digital Sky Survey and the SDSS-II Supernova Survey, we study the local environments of confirmed type Ia supernovae (SNe Ia) in the nearby universe. At 0.05 < z < 0.15, we find that SN Ia events in blue, star-forming galaxies occur preferentially in regions of lower ...

We describe a database of 431 low-dispersion optical spectra of 32 Type Ia supernovae (SNe Ia) that also have well-calibrated light curves. The coverage ranges from 6 epochs to 36 epochs of spectroscopy per SN, with over 200 spectra within 14 days of maximum. The consistency of the method of observation and the technique of reduction ...

Recent applications of type Ia supernovae (SNe Ia) in cosmology have successfully revealed the accelerating expansion of the universe. However, as distance indicators used in measuring the expansion history of the universe and probing the nature of dark energy, these objects must pass more strict tests. We propose a K-S test to investigate if there exists ...

We present ultraviolet, optical, and near-infrared photometry as well as optical spectra of the peculiar supernova (SN) 2008ha. SN 2008ha had a very low peak luminosity, reaching only MV = -14.2 mag, and low line velocities of only ~2000 km s-1 near maximum brightness, indicating a very small kinetic energy per unit mass of ejecta. Spectroscopically, ...

TypeIa supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a companion ...

Type Ia supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a ...

We present the results of an analysis of the world SNe data, complemented by a new dataset of low-redshift nearby-Hubble-flow SN Ia. This "Union" compilation of nearly 400 SN Ia includes the recent large samples of SNe Ia from the Supernova Legacy Survey and the ESSENCE Survey, the older ...

We present mid-infrared (5.2-15.2 ?m) spectra of the Type Ia supernovae (SNe Ia) 2003hv and 2005df observed with the Spitzer Space Telescope. These are the first observed mid-infrared spectra of thermonuclear supernovae, and show strong emission from fine-structure lines of Ni, Co, S, and Ar. The detection of Ni emission in SN 2005df ...

From the well-sampled light curves, we find that SN 2005cf reached a B-band maximum ... The UV light curves show similar evolution to the broadband ...

group trace elements in ~10 remnants of. SN Ia's. Trace Fe-group nucleosynthesis . Cas A: Fe-rich knots. In general nucleosynthesis at nuclear statistical ...

Staff Sunfall Documents For Students Internal Links Contact Type Ia Reddening Law paper by N. Chotard et al. 2011, A&A, 529, 4 SN2007if Host Properties paper by M. Childress...

the LC as a dark matter laboratory � Discover WIMPs and determine their properties � Consistency between of active participants. #12;Dark Energy � Positive pressure matter slows the expansion � Negative pressure matter speeds up the expansion � So SN IA results depend on matter- � These observations in wonderful

Type Ia SN 2003lx was first discovered in X-ray through two serendipitous Swift observations in 2008 January and the corresponding merged image revealed a 7-sigma source detection at 2.1pm1.2 arcsec (0.9 pm 0.5 Swift pixels) from the optical position of the supernova. We propose a XMM-Newton observation of Type Ia ...

Type Ia supernovae (SNe Ia) play an important role in the study of cosmic evolution, especially in cosmology. There are several progenitor models for SNe Ia proposed in the past years. By considering the effect of accretion disk instability on the evolution of white dwarf (WD) binaries, we performed detailed binary evolution ...

The Nearby Supernova Factory reports that a preliminary spectrum (range 320-1000 nm) of SN 2005eu (IAUC #8611), obtained Oct 6.5 UT with the Supernova Integral Field Spectrograph (SNIFS) on the University of Hawaii 2.2- meter telescope exhibits weak Si II 6100 AA absorption, Ca II IR triplet and S II "W." The supernova appears to be a Type Ia supernova ...

The discovery of SN 2002ic by the Supernova Factory and the subsequent spectroscopic studies have led to the surprising finding that SN 2002ic is a type Ia supernova with strong ejecta-circumstellar interaction. Here we show that nearly 1 year after the explosion the supernova has become fainter overall, but the H-alpha emission has ...

We present a new maximum-light optical spectrum of the extremely low luminosity and exceptionally low-energy Type Ia supernova (SN Ia) 2008ha, obtained one week before the earliest published spectrum. Previous observations of SN 2008ha were unable to distinguish between a massive star and white dwarf (WD) origin ...

We have used the Two Micron All Sky Survey near-infrared galaxy magnitudes to compute the supernova (SN) rates normalized to the stellar mass of the parent galaxies. The rates of all SN types show a sharp dependence on both the morphology and the B--K color of the galaxy. In particular,the Type Ia SN rate in the ...

We present optical photometry and spectra for the Type Ia supernova (SN Ia) 2007gi in the nearby galaxy NGC 4036. SN 2007gi is characterized by extremely high-velocity (HV) features of the intermediate-mass elements (Si, Ca, and S), with expansion velocities (v) approaching �15,500 km s near-maximum brightness ...

We know Type Ia supernovae are thermonuclear explosions of CO white dwarfs, but we don't know the specifics of how the nuclear burning proceeds from the core outward to the surface once it starts. Thermonuclear instability in a WD core is thought to start off as a subsonic, turbulent deflagration wave or "burning" wave but then may, at some point, transition into a supernova ...

We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z {le} 0.17 and 27 SN events in ...

We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z <= 0.17 and 27 SN events in ...

We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z {<=} 0.17 and 27 SN ...

We analyze the mean rest-frame ultraviolet (UV) spectrum of Type Ia Supernovae (SNe) and its dispersion using high signal-to-noise ratio Keck-I/LRIS-B spectroscopy for a sample of 36 events at intermediate redshift (z=0.5) discovered by the Canada-France-Hawaii Telescope Supernova Legacy Survey (SNLS). We introduce a new method for removing host galaxy contamination in our ...

The high-redshift SN Ia data are taken from the SNLS. This programme used optical imaging data taken as part of the deep component of the five-year Canada-France-Hawaii Telescope Legacy Survey (CFHT-LS) using the square-degree 'MegaCam' camera, located in the prime focus environment 'MegaPrime' on the CFHT. (1 data file).

Optical light curves and spectra of the Type Ia supernovae 1986G in NGC5128 (Centaurus A) are presented. SN 1986G was discovered approximately one week before maximum light. The initial rate of decline of the B light curve was remarkably fast and characte...

Type Ia supernovae and their remnants play a major role in several areas of astrophysics, including chemical evolution of galaxies and cosmology. Recent results suggest that at least some SNe Ia may result from more massive progenitor systems than normally assumed. Historical SN Ia in our Galaxy, ...

2006 astro-ph/0502262 Probing the curvature and dark energy Yungui Gong College of Electronic dark energy representations ! = ! 0 =(1 + z) and ! = ! 0 e z=(1+z) =(1 + z) are used to probe the geometry of the Universe and the property of dark energy. The combined type Ia supernova (SN Ia), Sloan

We discuss the emerging trend that super-Chandrasekhar Type Ia Supernovae (SCSNe) with progenitor mass estimates significantly exceeding ~1.4 M sun tend to explode in metal-poor environments. While Taubenberger et al. noted that some of the SCSNe host galaxies are relatively metal-poor, we focus quantitatively on their locations in the hosts to point out that in three out of ...

This is the third paper of a series in which we present new measurements of the observed rates of supernovae (SNe) in the local Universe, determined from the Lick Observatory Supernova Search (LOSS). We have considered a sample of �1000 SNe and used an optimal subsample of 726 SNe (274 SNe Ia, 116 SNe Ibc and 324 SNe II) to determine our rates. We study the trend of the ...

Timmes et al. found that metallicity variations could theoretically account for a 25% variation in the mass of 56Ni synthesized in Type Ia supernovae (SNe Ia), and thus account for a large fraction of the scatter in observed SN Ia luminosities. Higher-metallicity progenitors are more neutron rich, producing more ...

Late-time (t ~ 300 d) observation of near-infrared (NIR) [Fe II] lines has proven to be a very powerful tool for probing the physics of Type Ia supernova (SN Ia) explosions. The few available examples have revealed that at least some SNe Ia exhibit a layered ejecta structure which persists down to the innermost ...

We present an empirical method to measure precise distances from type Ia supernova (SN Ia) light curves and apply it to estimate cosmological parameters. This multi-color light curve shape (MLCS) method derives the empirical relationship between light and color curve shape and luminosity to distinguish between SNe ...

We present optical (UBVRI) and near-IR (YJHK) photometry of the normal Type Ia supernova (SN) 2004S. We also present eight optical spectra and one near-IR spectrum of SN 2004S. The light curves and spectra are nearly identical to those of SN 2001el. This is the first time we have seen optical and IR light curves of ...

We obtained optical photometry of SN 2003gs on 49 nights, from 2 to 494 days after T(B {sub max}). We also obtained near-IR photometry on 21 nights. SN 2003gs was the first fast declining Type Ia SN that has been well observed since SN 1999by. While it was subluminous in optical bands compared ...

The purpose of this work is the computation of the cosmic Type Ia supernova rates, namely the frequency of Type Ia supernovae per unit time in a unitary volume of the Universe. Our main goal in this work is to predict the Type Ia supernova rates at very high redshifts and to check whether it is possible to select the best delay time ...

Recovery of the supernova (SN) delay-time distribution (DTD) - the SN rate versus time that would follow a hypothetical brief burst of star formation - can shed light on SN progenitors and physics, as well as on the time-scales of chemical enrichment. Previous attempts to reconstruct the DTD have been based either on comparison of mean ...

This paper presents an LTE analysis of the photospheric epoch optical and IUE UV spectra of the recent Type Ia supernovae SN 1990N and SN 1991T. It is found that SN 1990N has matter moving as fast as 40,000 km/s, while SN 1991T has matter moving as fast as 20,000 km/s. The exponential density ...

The Gamow-Teller resonances (GTR) and isobaric analog states (IAS) of a sequence of even-even Sn target nuclei are calculated by using the framework of the relativistic Hartree-Bogoliubov model plus proton-neutron quasiparticle random-phase approximation. The calculation reproduces the experimental data on ground-state properties, as well as the excitation ...

The Gamow-Teller resonances (GTR) and isobaric analog states (IAS) of a sequence of even-even Sn target nuclei are calculated by using the framework of the relativistic Hartree-Bogoliubov model plus proton-neutron quasiparticle random-phase approximation. The calculation reproduces the experimental data on ground-state properties, as well as the excitation ...

Understanding the light curves of Type Ia Supernovae (SNe Ia) is essential to their use as standard candles in cosmological studies. Recent observations of SNe Ia have shown brighter than expected NIR emission at very late phases resulting in brighter than expected bolometric luminosity at that epoch. Also, some observations showed ...

We present the first mid-infrared (5.2-15.2 micron) spectra of Type Ia supernovae (SNe 2003hv and 2005df). The detection of Ni emission in SN 2005df 135 days after the explosion provides direct observational evidence of high-density nuclear burning forming a significant amount of stable Ni in a Type Ia supernova. The observed emission ...

Optical spectroscopy and photometry of the Type Ia supernova SN 1988G obtained shortly after dicovery are presented. The redshift of the parent galaxy is determined to be 7055 km/sec. Adopting a distance of 88 Mpc, the supernova has an absolute magnitude of M(B) = -18.8. Based on the luminosity and the characteristics displayed by the optical spectrum it ...

We show that the cosmic microwave background (CMB) data of WMAP can give subelectronvolt limit on the neutrino mass. We investigate how much we can make it more stringent by using 'standard ruler' measurements such as baryon acoustic oscillation (BAO) and type Ia supernovae (SN)

19 y-1 SN Ia within D = 50 Mpc (Peak 847 keV Flux e 1.2 10-6 cm-2 s-1) ... SN Iln (bright only) D < 8 Mpc. Plan in place for extensive coverage of ...

We present an analysis of the rise-time distribution of nearby (z< 0.05) Type Ia supernovae (SNe Ia). Drawing mostly from the recently published Lick Observatory Supernova Search (LOSS) SN Ia sample along with other published nearby SNe Ia with data starting at least ten days before maximum ...

Knowledge of the supernova (SN) delay time distribution (DTD)�the SN rate versus time that would follow a hypothetical brief burst of star formation�can shed light on SN progenitors and physics, as well as on the timescales of chemical enrichment in different environments. We compile recent measurements of the ...

Knowledge of the supernova (SN) delay time distribution (DTD)-the SN rate versus time that would follow a hypothetical brief burst of star formation-can shed light on SN progenitors and physics, as well as on the timescales of chemical enrichment in different environments. We compile recent measurements of the ...

With a redshift of z {approx} 1.7, SN 1997ff is the most distant type Ia supernova discovered so far. This SN is close to several bright, z = 0.6-0.9 galaxies, and we consider the effects of lensing by those objects on the magnitude of SN 1997ff. We estimate their velocity dispersions using the Tully-Fisher and ...

We present the discovery, photometric, and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with ? d = 5 days and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M r = -17 mag and has mean velocities of 10,000 km s-1. Our light curve modeling suggests a ...

We analyze the mean rest-frame ultraviolet (UV) spectrum ofType Ia Supernovae(SNe) and its dispersion using high signal-to-noiseKeck-I/LRIS-B spectroscopyfor a sample of 36 events at intermediateredshift (z=0.5) discoveredby the Canada-France-Hawaii TelescopeSupernova Legacy Survey (SNLS). Weintroduce a new method for removinghost galaxy contamination in our spectra,exploiting ...

The spectral signatures of asymmetry in Type Ia Supernova (SN Ia) explosions are investigated, using a sample of late-time nebular spectra. First, a kinematical model is constructed for SN Ia 2003hv, which can account for the main features in its optical, Near-Infrared (NIR), and Mid-Infrared ...

We compare the B-band light curves for 11 normal and 7 peculiar 91T/99aa-like Type Ia supernovae, all found from low-redshift searches. Each was chosen based on two criteria: 1) the SN was spectroscopically identified as either ``normal'' (i.e., resembling SNe 1990N, 1992A, 1992al) or ``peculiar'' (i.e., resembling SN 1991T, or ...

We rank the six latest Type Ia supernova (SnIa) datasets (Constitution (C), Union (U), ESSENCE (Davis) (E), Gold06 (G), SNLS 1yr (S) and SDSS-II (D)) in the context of the Chevalier-Polarski-Linder (CPL) parametrization w(a) = w0+w1(1-a), according to their Figure of Merit (FoM), their consistency with the cosmological constant (?CDM), their consistency ...

Constraints on dark energy from current observational data are sensitive to how distances are measured from Type Ia supernova (SN Ia) data. We find that flux averaging of SNe Ia can be used to test the presence of unknown systematic uncertainties, and yield more robust distance measurements from SNe ...

The rate of subluminous Type I SNs (Type Ib) is computed by means of galactic evolutionary models and compared with that of classical Type I SNs (Type Ia) in the Galaxy and in ellipticals. The assumed progenitors for Type Ib SNs are binary systems consisting of a C-O degenerate dwarf plus a nondegenerate He star, whereas those for Type Ia are binary ...

We present four spectra of the Type Ia supernova SN Ia 2006Dextending from -7 to +13 days with respect to B-band maximum. The spectrainclude the strongest signature of unburned material at photosphericvelocities observed in a SN Ia to date. The earliest spectrum exhibits CII absorption features ...

The use of type Ia supernova (SN Ia) as standard candles has shifted from testing whether the Universe is accelerating to making a precision measurement of the dark energy equation of state to test the current Lambda-CDM paradigm. However, we still lack a clear understanding of the SN Ia ...

An analysis of the effect of microlensing by a cosmologically dominant density of compact objects is performed, using high-redshift Type Ia supernovae (SN Ia's) as probes. The compact objects are modeled as a three-dimensional distribution of point masses, and Monte Carlo simulations are done to calculate the resulting ...

We report photometric observations of two nearby type Ia supernovae, SN 1994ae and SN 1998aq, and the farthest direct observations of Cepheids, using the Advanced Camera for Surveys on HST. Both of these SNe Ia are spectroscopically and photometrically normal with low-reddening, precise and complete light curves ...

The rate of occurrence of supernovae (SNe) is linked to some of the basic ingredients of galaxy evolution, such as the star formation rate, the chemical enrichment and feedback processes. SN rates at intermediate redshift and their dependence on specific galaxy properties have been investigated in the Southern inTermediate Redshift ESO Supernova Search (STRESS). The rate of ...

We present VRIJHK photometry, and optical and near-infrared spectroscopy, of the heavily extinguished Type Ia supernova (SN Ia) 2002cv, located in NGC 3190, which is also the parent galaxy of the SN Ia 2002bo. SN 2002cv, not visible in the blue, has a total visual ...

We have obtained optical spectra of 29 early-type (E/S0) galaxies that hosted Type Ia supernovae (SNe Ia). We have measured absorption-line strengths and compared them to a grid of models to extract the relations between the supernova properties and the luminosity-weighted age/composition of the host galaxies. Such a direct measurement is a marked ...

A. Gal-Yam, D. Sand and D. Leonard report for the CCCP: We have observed SN 2005dh (Moore &Li ; IAUC #8583 ) and SN 2005di (Pugh & Li; CBET #198) with the DBSP spectrograph mounted on the Hale 200" telescope at Palomar Observatory on 2005 August 14 UT. Reductions of the red-side spectra confirm that SN 2005dh is indeed of type ...

Prior to the explosive burning of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star "simmers" for ~103 yr in a convecting, carbon-burning region. I estimate the excitation of g-modes by convection during this phase and explore their possible effect on the WD. As these modes propagate from the core of the WD toward its ...

Prior to the incineration of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star ``simmers'' for ~1000 yr in a convecting, carbon-burning region. We have found that weak interactions during this time increase the neutron excess by an amount that depends on the total quantity of carbon burned prior to the explosion. This ...

Prior to the explosive burning of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star "simmers" for ~10^3 yrs in a convecting, carbon burning region. I estimate the excitation of g-modes by convection during this phase and explore their possible affect on the WD. As these modes propagate from the core of the WD toward ...

We explore the relationship between the models for progenitor systems of Type Ia supernovae and the properties of the supernova remnants that evolve after the explosion. Most models for Type Ia progenitors in the single-degenerate scenario predict substantial outflows during the presupernova evolution. Expanding on previous work, we estimate the imprint of ...

We present a comprehensive statistical analysis of the properties of Type Ia supernova (SN Ia) light curves in the near-infrared using recent data from Peters Automated InfraRed Imaging TELescope and the literature. We construct a hierarchical Bayesian framework, incorporating several uncertainties including photometric error, peculiar ...

We present photometric and spectroscopic observations of SN 2007if, an overluminous (MV = -20.4), red (B - V = 0.16 at B-band maximum), slow-rising (t rise = 24 days) type Ia supernova (SN Ia) in a very faint (Mg = -14.10) host galaxy. A spectrum at 5 days past B-band maximum light is a direct match to the ...

We investigate two potential mechanisms that will produce X-ray and ?-ray flashes from Type Ia supernovae (SN-Ia). The first mechanism is the breakout of the thermonuclear burning front as it reaches the surface of the white dwarf (WD). The second mechanism is the interaction of the rapidly expanding envelope with material within an accretion disk in the ...

We investigate two potential mechanisms that will produce X-ray and gamma-ray flashes from Type Ia supernovae (SN-Ia). The first mechanism is the breakout of the thermonuclear burning front as it reaches the surface of the white dwarf (WD). The second mechanism is the interaction of the rapidly expanding envelope with material within an accretion disk in ...

The sample of 137 low-redshift type Ia supernovae (SNe Ia) with 0.05 {<=} z {<=} 0.3 obtained from the Sloan Digital Sky Survey (SDSS)-II supernova survey for the southern equatorial stripe of 300 deg{sup 2} is used to derive the luminosity functions (LFs) of SNe Ia and of their host galaxies in the g, r, i passbands. We ...

For more than a decade observations and analyses of type Ia supernova (SNe Ia) explosions have resulted in profound insights into the nature of our universe. However, in spite of the amazing discoveries, the list of fundamental things that we still do not understand about SNe Ia is quite long. We attempt to address a few of these ...

Extended optical and near-IR observations reveal that SN 2009dc shares a number of similarities with normal Type Ia supernovae (SNe Ia), but is clearly overluminous, with a (pseudo-bolometric) peak luminosity of log (L) = 43.47 (erg s-1). Its light curves decline slowly over half a year after maximum light [?m15(B)true= 0.71], and the ...

Aims: Recurrent nova systems like RS Oph have been proposed as a possible channel for type Ia supernova (SN) explosions based on the high mass of the accreting white dwarf. Additional support for this hypothesis has recently been provided by the detection of circumstellar material around SN 2006X and SN 2007le, ...

This paper exploits the gravitational magnification of Type Ia supernovae (SNe Ia) to measure properties of dark matter haloes. Gravitationally magnified and de-magnified SNe Ia should be brighter and fainter than average, respectively. The magnification of individual SNe Ia can be computed using observed ...

We present an analysis of the B- and V-band rise-time distributions of nearby Type Ia supernovae (SNe Ia). Drawing mostly from the recently published Lick Observatory Supernova Search sample of SNe Ia, together with other published nearby SNe Ia with data starting at least 1 week before maximum light, we use a ...

We present an analysis of the B- and V-band rise-time distributions of nearby Type Ia supernovae (SNe Ia). Drawing mostly from the recently published Lick Observatory Supernova Search sample of SNe Ia, together with other published nearby SNe Ia with data starting at least 1 week before maximum light, we use a ...

The remarkable uniformity of Type Ia supernovae has allowed astronomers to use them as distance indicators to measure the properties and expansion history of the Universe. However, Type Ia supernovae exhibit intrinsic variation in both their spectra and observed brightness. The brightness variations have been approximately corrected by various methods, but ...

We use a sample of 121 spectroscopically normal Type Ia supernovae (SNe Ia) to show that their intrinsic color is correlated with their ejecta velocity, as measured from the blueshift of the Si II ?6355 feature near maximum brightness, v Si II . The SN Ia sample was originally used by Wang et al. to show that the ...

From Sloan Digital Sky Survey u{prime} g{prime} r{prime} i{prime} z{prime} imaging, we estimate the stellar masses of the host galaxies of 70 low redshift SN Ia (0.015 < z < 0.08) from the hosts absolute luminosities and mass-to-light ratios. These nearby SN were discovered largely by searches targeting luminous galaxies, ...

Although the nature of the progenitor of Type Ia supernovae (SNe Ia) is still unclear, the single-degenerate (SD) channel for the progenitor is currently accepted, in which a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from its companion, increases its mass to the Chandrasekhar mass limit, and then explodes as an ...

We present extensive optical (UBVRI), near-infrared (JK) light curves and optical spectroscopy of the Type Ia supernova SN 2006X in the nearby galaxy NGC 4321 (M100). Our observations suggest that either SN 2006X has an intrinsically peculiar color evolution or it is highly reddened [E(B-V)host=1.42+/-0.04 mag] with RV=1.48+/-0.06, ...

The thermonuclear explosion of a carbon-oxygen white dwarf that has accreted mass until it approaches the Chandrasekhar limit is widely accepted to be the correct model for Type Ia supernovae (SN Ia). The basic observational characteristics of these models are in general agreement with the observed composition, light curves, and ...

The distribution of absolute blue magnitudes among Type Ia supernovae (SNs Ia) is studied. Supernovae were used with well determined apparent magnitudes at maximum light and parent galaxies with relative distances determined by the Tully-Fisher or Dn - sigma techniques. The mean absolute blue magnitude is given and the observational dispersion is only ...

In 293 cells, splicing of the human fibroblast growth factor receptor-2 K-SAM alternative exon is inefficient, but can be made efficient by provoking TIA-1 binding to the U-rich IAS1 sequence downstream from the exon's 5' splice site. We show here that TIA-1 domains known to interact with U1 snRNP and to recruit it to 5' splice ...

The single-degenerate (SD) channel for the progenitors of type Ia supernovae (SNe Ia) is one of the most popular channels, in which a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from its companion, increases its mass to the Chandrasekhar mass limit, and then explodes as a SN Ia. We show the ...

Large photometric surveys of transient phenomena, such as Panoramic Survey Telescope and Rapid Response System and Large Synoptic Survey Telescope, will locate thousands to millions of Type Ia supernova (SN Ia) candidates per year, a rate prohibitive for acquiring spectroscopy to determine each candidate's type and redshift. ...

The S0 galaxy NGC 4526 in the Virgo Cluster hosted the well observed type Ia supernova 1994D. Richmond et al. (1995, AJ 109,2121) quote a brightness excess of ~ 0.5 mag with respect to SN 1980N and SN 1989B, thus questioning the standard candle paradigm for type Ia SNe. Tammann & Sandage (1996, ApJ 452,16) ...

We examine recent evidence from the luminosity-redshift relation of Type Ia Supernovae for the {approx} 3 {sigma} detection of a ''Hubble bubble'' -- a departure of the local value of the Hubble constant from its globally averaged value. By comparing the MLCS2k2 fits used in that study to the results from other light-curve fitters applied to ...

Aims: We present 139 spectra of 124 Type Ia supernovae (SNe Ia) that were observed at the ESO/VLT during the first three years of the Canada-France-Hawa� Telescope (CFHT) supernova legacy survey (SNLS). This homogeneous data set is used to test for redshift evolution of SN Ia spectra, and will be used in the SNLS ...

We present photometric and spectroscopic observations of the Type Ia supernova SN 2009nr in UGC 8255 (z = 0.0122). Following the discovery announcement at what turned out to be 10 days after peak, we detected it at V sime15.7 mag in data collected by the All-Sky Automated Survey (ASAS) North telescope 2 weeks prior to the peak, and then followed it up with ...

The giant elliptical galaxy NGC 1316 (Fornax A) is a well-studied member of the Fornax Cluster and a prolific producer of Type Ia supernovae (SNe Ia), having hosted four observed events since 1980. Here, we present detailed optical- and near-infrared light curves of the spectroscopically normal SN 2006dd. These data are used, along ...

The giant elliptical galaxy NGC 1316 (Fornax A) is a well-studied member of the Fornax Cluster and a prolific producer of Type Ia supernovae (SNe Ia), having hosted four observed events since 1980. Here, we present detailed optical- and near-infrared light curves of the spectroscopically normal SN 2006dd. These data are used, along ...