- ID:
- ivo://CDS.VizieR/J/ApJ/666/674
- Title:
- ESSENCE supernova survey
- Short Name:
- J/ApJ/666/674
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the implementation and optimization of the ESSENCE supernova survey, which we have undertaken to measure the dark energy equation-of-state parameter, w=P/({rho}c^2^). We present a method for optimizing the survey exposure times and cadence to maximize our sensitivity to w for a given fixed amount of telescope time. For our survey on the CTIO 4m telescope, measuring the luminosity distances and redshifts for supernovae at modest redshifts (z~0.5+/-0.2) is optimal for determining w. We describe the data analysis pipeline based on using reliable and robust image subtraction to find supernovae automatically and in nearly real time.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/224/3
- Title:
- ESSENCE 6yr spectroscopic follow-up
- Short Name:
- J/ApJS/224/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Equation of State: Supernovae trace Cosmic Expansion (ESSENCE) survey discovered 213 Type Ia supernovae at redshifts 0.1<z<0.81 between 2002 and 2008. We present their R- and I-band photometry, measured from images obtained using the MOSAIC II camera at the CTIO Blanco, along with rapid-response spectroscopy for each object. We use our spectroscopic follow-up observations to determine an accurate, quantitative classification, and precise redshift. Through an extensive calibration program we have improved the precision of the CTIO Blanco natural photometric system. We use several empirical metrics to measure our internal photometric consistency and our absolute calibration of the survey. We assess the effect of various potential sources of systematic bias on our measured fluxes, and estimate the dominant term in the systematic error budget from the photometric calibration on our absolute fluxes is ~1%.
- ID:
- ivo://CDS.VizieR/J/ApJ/608/405
- Title:
- Explosive yields of massive star (Z=0-Z_{sun}_)
- Short Name:
- J/ApJ/608/405
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new and homogeneous set of explosive yields for masses 13, 15, 20, 25, 30, and 35M_{sun}_ and metallicities Z=0, 10^-6^, 10^-4^, 10^-3^, 6x10^-3^, and 2x10^-2^. A wide network extending up to Mo has been used in all computations. We show that at low metallicities (Z<=10^-4^), the final yields do not depend significantly on the initial chemical composition of the models, so a scaled solar distribution may be safely assumed at all metallicities. Moreover, no elements above Zn are produced by any mass in the grid up to a metallicity ~10-3. These yields are available for any choice of the mass cut on request.
- ID:
- ivo://CDS.VizieR/J/MNRAS/328/1181
- Title:
- Extragalactic supernovae
- Short Name:
- J/MNRAS/328/1181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In order to investigate the influence of environment on supernova (SN) production, we have performed a statistical investigation of the SNe discovered in isolated galaxies, in pairs and in groups of galaxies. 22 SNe in 18 isolated galaxies, 48 SNe in 40 galaxy members of 37 pairs and 211 SNe in 170 galaxy members of 116 groups have been selected and studied.
- ID:
- ivo://CDS.VizieR/J/other/Sci/340.45
- Title:
- Fast shocks around SN 1006
- Short Name:
- J/other/Sci/340.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Supernova remnants are among the most spectacular examples of astrophysical pistons in our cosmic neighborhood. The gas expelled by the supernova explosion is launched with velocities ~1000 kilometers per second into the ambient, tenuous interstellar medium, producing shocks that excite hydrogen lines. We have used an optical integral-field spectrograph to obtain high-resolution spatial-spectral maps that allow us to study in detail the shocks in the northwestern rim of supernova 1006. The two-component H{alpha} line is detected at 133 sky locations. Variations in the broad line widths and the broad-to-narrow line intensity ratios across tens of atomic mean free paths suggest the presence of suprathermal protons, the potential seed particles for generating high-energy cosmic rays.
- ID:
- ivo://CDS.VizieR/J/A+A/554/A27
- Title:
- 2011fe spectrophotometric time series
- Short Name:
- J/A+A/554/A27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 32 epochs of optical (3300-9700{AA}) spectrophotometric observations of the nearby quintessential "normal" type Ia supernova (SN Ia) SN 2011fe in the galaxy M101, extending from -15 to +97d with respect to B-band maximum, obtained by the Nearby Supernova Factory collaboration. SN 2011fe is the closest ({mu}=29.04) and brightest (Bmax=9.94mag) SN Ia observed since the advent of modern large scale programs for the intensive periodic followup of supernovae. Both synthetic light curve measurements and spectral feature analysis attest to the normality of SN 2011fe. There is very little evidence for reddening in its host galaxy. The homogeneous calibration, intensive time sampling, and high signal-to-noise ratio of the data set make it unique. Thus it is ideal for studying the physics of SN Ia explosions in detail, and for furthering the use of SNe Ia as standardizable candles for cosmology.
- ID:
- ivo://CDS.VizieR/J/MNRAS/438/L101
- Title:
- First month on SN 2013ej
- Short Name:
- J/MNRAS/438/L101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present early photometric and spectroscopic observations of SN 2013ej, a bright Type IIP supernova (SN) in M74. SN 2013ej is one of the closest SNe ever discovered. The available archive images and the early discovery help to constrain the nature of its progenitor. The earliest detection of this explosion was on 2013 July 24.125 ut and our spectroscopic monitoring with the FLOYDS spectrographs began on July 27.7 ut, continuing almost daily for two weeks. Daily optical photometric monitoring was achieved with the 1m telescopes of the Las Cumbres Observatory Global Telescope (LCOGT) network, and was complemented by UV data from Swift and near-infrared spectra from Public ESO Spectroscopic Survey of Transient Objects and Infrared Telescope Facility. The data from our monitoring campaign show that SN 2013ej experienced a 10d rise before entering into a well-defined plateau phase. This unusually long rise time for a Type IIP has been seen previously in SN 2006bp and SN 2009bw. A relatively rare strong absorption blueward of H{alpha} is present since our earliest spectrum. We identify this feature as SiII, rather than high-velocity H{alpha} as sometimes reported in the literature.
- ID:
- ivo://CDS.VizieR/J/ApJS/185/32
- Title:
- First-year SDSS-II SN results
- Short Name:
- J/ApJS/185/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present measurements of the Hubble diagram for 103 Type Ia supernovae (SNe) with redshifts 0.04<z<0.42, discovered during the first season (Fall 2005) of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. These data fill in the redshift "desert" between low- and high-redshift SN Ia surveys. Within the framework of the MLCS2K2 light-curve fitting method, we use the SDSS-II SN sample to infer the mean reddening parameter for host galaxies, R_V_=2.18+/-0.14_stat_+/-0.48_syst_, and find that the intrinsic distribution of host-galaxy extinction is well fitted by an exponential function, P(A_V_)=exp(-A_V_/{tau}_V_), with {tau}_V_=0.334+/-0.088mag. We combine the SDSS-II measurements with new distance estimates for published SN data from the ESSENCE survey, the Supernova Legacy Survey (SNLS), the Hubble Space Telescope (HST), and a compilation of Nearby SN Ia measurements. A new feature in our analysis is the use of detailed Monte Carlo simulations of all surveys to account for selection biases, including those from spectroscopic targeting.
- ID:
- ivo://CDS.VizieR/J/AJ/152/102
- Title:
- Flux conversion factors for the Swift/UVOT filters
- Short Name:
- J/AJ/152/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the transformation of observed photometry into flux for the creation of spectral energy distributions (SED) and the computation of bolometric luminosities. We do this in the context of supernova studies, particularly as observed with the Swift spacecraft, but the concepts and techniques should be applicable to many other types of sources and wavelength regimes. Traditional methods of converting observed magnitudes to flux densities are not very accurate when applied to UV photometry. Common methods for extinction and the integration of pseudo-bolometric fluxes can also lead to inaccurate results. The sources of inaccuracy, though, also apply to other wavelengths. Because of the complicated nature of translating broadband photometry into monochromatic flux densities, comparison between observed photometry and a spectroscopic model is best done by forward modeling the spectrum into the count rates or magnitudes of the observations. We recommend that integrated flux measurements be made using a spectrum or SED which is consistent with the multi-band photometry rather than converting individual photometric measurements to flux densities, linearly interpolating between the points, and integrating. We also highlight some specific areas where the UV flux can be mischaracterized.
- ID:
- ivo://CDS.VizieR/J/ApJ/826/144
- Title:
- Follow-up observations of SNIa ASASSN-14lp
- Short Name:
- J/ApJ/826/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On 2014 December 9.61, the All-sky Automated Survey for SuperNovae (ASAS-SN or "Assassin") discovered ASASSN-14lp just ~2 days after first light using a global array of 14cm diameter telescopes. ASASSN-14lp went on to become a bright supernova (V=11.94mag), second only to SN 2014J for the year. We present prediscovery photometry (with a detection less than a day after first light) and ultraviolet through near-infrared photometric and spectroscopic data covering the rise and fall of ASASSN-14lp for more than 100 days. We find that ASASSN-14lp had a broad light curve ({Delta}m_15_(B)=0.80+/-0.05), a B-band maximum at 2457015.82+/-0.03, a rise time of 16.94_-0.10_^+0.11^days, and moderate host-galaxy extinction (E(B-V)_host_=0.33+/-0.06). Using ASASSN-14lp, we derive a distance modulus for NGC 4666 of {mu}=30.8+/-0.2, corresponding to a distance of 14.7+/-1.5Mpc. However, adding ASASSN-14lp to the calibrating sample of Type Ia supernovae still requires an independent distance to the host galaxy. Finally, using our early-time photometric and spectroscopic observations, we rule out red giant secondaries and, assuming a favorable viewing angle and explosion time, any nondegenerate companion larger than 0.34R_{sun}_.
