- ID:
- ivo://CDS.VizieR/J/ApJ/835/166
- Title:
- SNe type II from CSP-I, SDSS-II, and SNLS
- Short Name:
- J/ApJ/835/166
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The coming era of large photometric wide-field surveys will increase the detection rate of supernovae by orders of magnitude. Such numbers will restrict spectroscopic follow-up in the vast majority of cases, and hence new methods based solely on photometric data must be developed. Here, we construct a complete Hubble diagram of Type II supernovae (SNe II) combining data from three different samples: the Carnegie Supernova Project-I, the Sloan Digital Sky Survey II SN, and the Supernova Legacy Survey. Applying the Photometric Color Method (PCM) to 73 SNe II with a redshift range of 0.01-0.5 and with no spectral information, we derive an intrinsic dispersion of 0.35mag. A comparison with the Standard Candle Method (SCM) using 61 SNe II is also performed and an intrinsic dispersion in the Hubble diagram of 0.27mag, i.e., 13% in distance uncertainties, is derived. Due to the lack of good statistics at higher redshifts for both methods, only weak constraints on the cosmological parameters are obtained. However, assuming a flat universe and using the PCM, we derive the universe's matter density: {Omega}_m_=0.32_-0.21_^+0.30^ providing a new independent evidence for dark energy at the level of two sigma.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/738/162
- Title:
- SN Ia candidates from the SDSS-II SN Survey
- Short Name:
- J/ApJ/738/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 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 subset of 210 candidates having spectroscopic redshifts of their host galaxies measured while the remaining 860 candidates are purely photometric in their identification. We describe a method for estimating the efficiency and purity of photometric SN Ia classification when spectroscopic confirmation of only a limited sample is available, and demonstrate that SN Ia candidates from SDSS-II can be identified photometrically with ~91% efficiency and with a contamination of ~6%. Although this is the largest uniform sample of SN candidates to date for studying photometric identification, we find that a larger spectroscopic sample of contaminating sources is required to obtain a better characterization of the background events. A Hubble diagram using SN candidates with no spectroscopic confirmation, but with host galaxy spectroscopic redshifts, yields a distance modulus dispersion that is only ~20%-40% larger than that of the spectroscopically confirmed SN Ia sample alone with no significant bias. A Hubble diagram with purely photometric classification and redshift-distance measurements, however, exhibits biases that require further investigation for precision cosmology.
- ID:
- ivo://CDS.VizieR/J/ApJ/755/61
- Title:
- SN Ia host galaxies SFR from SDSS-II
- Short Name:
- J/ApJ/755/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using data from the Sloan Digital Sky Supernova Survey-II (SDSS-II SN Survey, Frieman et al., 2008AJ....135..338F), 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<z<0.25 is constructed. Using broadband photometry and redshifts, we use the P\'EGASE.2 spectral energy distributions to estimate host galaxy stellar masses and recent star formation rates (SFRs).
- ID:
- ivo://CDS.VizieR/J/ApJ/713/1026
- Title:
- SN Ia rate at redshift <~0.3 from SDSS-II
- Short Name:
- J/ApJ/713/1026
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 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 Ia. The remaining 246 SNe Ia were identified through their light curves; 113 of these objects have spectroscopic redshifts from spectra of their host galaxy, and 133 have photometric redshifts estimated from the SN light curves. Based on consideration of 87 spectroscopically confirmed non-Ia SNe discovered by the SDSS-II SN Survey, we estimate that 2.04^+1.61^_-0.95_% of the photometric SNe Ia may be misidentified. The sample of SNe Ia used in this measurement represents an order of magnitude increase in the statistics for SN Ia rate measurements in the redshift range covered by the SDSS-II Supernova Survey.
- ID:
- ivo://CDS.VizieR/J/ApJS/217/12
- Title:
- S7 observations with WiFeS of active galaxies
- Short Name:
- J/ApJS/217/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Here we describe the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph (WiFeS) mounted on the ANU 2.3m telescope located at the Siding Spring Observatory to deliver an integral field of 38x25 arcsec at a spectral resolution of R=7000 in the red (530-710nm), and R=3000 in the blue (340-560nm). From these data cubes we have extracted the narrow-line region spectra from a 4 arcsec aperture centered on the nucleus. We also determine the H{beta} and [OIII]{lambda}5007 fluxes in the narrow lines, the nuclear reddening, the reddening-corrected relative intensities of the observed emission lines, and the H{beta} and [OIII]{lambda}5007 luminosities determined from spectra for which the stellar continuum has been removed. We present a set of images of the galaxies in [OIII]{lambda}5007, [NII]{lambda}6584, and H{alpha}, which serve to delineate the spatial extent of the extended narrow-line region and also to reveal the structure and morphology of the surrounding HII regions. Finally, we provide a preliminary discussion of those Seyfert 1 and Seyfert 2 galaxies that display coronal emission lines in order to explore the origin of these lines.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1247
- Title:
- Solar system survey with Spacewatch
- Short Name:
- J/AJ/133/1247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have completed a low-inclination ecliptic survey for distant and slow-moving bright objects in the outer solar system. This survey used data taken over 34 months by the University of Arizona's Spacewatch Project based at Steward Observatory, Kitt Peak. Spacewatch revisits the same sky area every three to seven nights in order to track cohorts of main-belt asteroids. This survey used a multiple-night detection scheme to extend our rate sensitivity to as low as 0.012"/hr. When combined with our plate scale and flux sensitivity (V~21), this survey was sensitive to Mars-sized objects out to 300AU and Jupiter-sized planets out to 1200AU. The survey covered approximately 8000deg^2^ of raw sky, mostly within 10{deg} of the ecliptic but away from the Galactic center. An automated motion detection program was modified for this multinight search and processed approximately 2 terabytes of imagery into motion candidates. This survey discovered 2003 MW12, currently the tenth largest classical Kuiper Belt object. In addition, several known large Kuiper Belt objects and Centaurs were detected, and the detections were used with a model of our observational biases to make population estimates as a check on our survey efficiency. We found no large objects at low inclinations despite having sufficient sensitivity in both flux and rate to see them out as far as 1200AU. For low inclinations, we can rule out more than one to two Pluto-sized objects out to 100AU and one to two Mars-sized objects to 200AU.
- ID:
- ivo://CDS.VizieR/J/A+A/650/A39
- Title:
- SOPHIE and HARPS Young Nearby Stars - YNS
- Short Name:
- J/A+A/650/A39
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The search of close (a<~5au) giant planet (GP) companions with radial velocity (RV) around young stars and the estimate of their occurrence rates is important to constrain the migration timescales. Furthermore, this search will allow the giant planet occurrence rates to be computed at all separations via the combination with direct imaging techniques. The RV search around young stars is a challenge as they are generally faster rotators than older stars of similar spectral types and they exhibit signatures of magnetic activity (spots) or pulsation in their RV time series. Specific analyses are necessary to characterize, and possibly correct for, this activity. Our aim is to search for planets around young nearby stars and to estimate the GP occurrence rates for periods up to 1000 days. We used the SOPHIE spectrograph on the 1.93m telescope at the Haute-Provence Observatory to observe 63 A-M young (<400Myr) stars. We used our Spectroscopic data via Analysis of the Fourier Interspectrum Radial velocities (SAFIR) software to compute the RVs and other spectroscopic observables. We then combined this survey with the HARPS YNS survey to compute the companion occurrence rates on a total of 120 young A-M stars. Results. We report one new trend compatible with a planetary companion on HD 109647. We also report HD 105693 and HD 112097 as binaries, and we confirm the binarity of HD 2454, HD13531, HD 17250 A, HD 28945, HD 39587, HD 131156, HD 142229, HD 186704 A, and HD 195943. We constrained for the first time the orbital parameters of HD 195943 B. We refute the HD 13507 single brown dwarf (BD) companion solution and propose a double BD companion solution. Two GPs were previously reported from this survey in the HD 113337 system. Based on our sample of 120 young stars, we obtain a GP occurrence rate of 1^+2/2^_0/3_% for periods lower than 1000 days, and we obtain an upper limit on BD occurrence rate of 0.9^+2^_0.9_% in the same period range. We report a possible lack of close (P {in} [1; 1000] days) GPs around young FK stars compared to their older counterparts, with a confidence level of 90%.
- ID:
- ivo://CDS.VizieR/J/A+A/467/585
- Title:
- Sources detected by ISGRI
- Short Name:
- J/A+A/467/585
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In its first 4 years of observing the sky above 20keV, INTEGRAL-ISGRI has detected 500 sources, around half of which are new or unknown at these energies. Follow-up observations at other wavelengths revealed that some of these sources feature unusually large column densities, long pulsations, and other interesting characteristics. We investigate where new and previously-known sources detected by ISGRI fit in the parameter space of high-energy objects, and we use the parameters to test correlations expected from theoretical predictions. For example, the influence of the local absorbing matter on periodic modulations is studied for Galactic High-Mass X-ray Binaries (HMXBs) with OB supergiant and Be companions. We examine the spatial distribution of different types of sources in the Milky Way using various projections of the Galactic plane, in order to highlight signatures of stellar evolution and to speculate on the origin of the group of sources whose classifications are still uncertain.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2251
- Title:
- Southern Catalina Survey type-ab RR Lyrae
- Short Name:
- J/MNRAS/446/2251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a deep, wide-area variability survey in the Southern hemisphere. As part of the Catalina Sky Surveys, the Siding Spring Survey (SSS) has covered 14,800 square degrees in the declination range of -75{deg}<delta<-15{deg} To mine the enormous SSS dataset efficiently we have developed two algorithms: Automatic Period Selection (APS) and Automatic Fourier Decomposition (AFD), which aim to sharpen the period estimation and produce robust lightcurve models. Armed with the APS and AFD outputs we classify 10540 ab-type RR Lyrae (RRab) stars (~90% of which are new) across the Southern sky.
- ID:
- ivo://CDS.VizieR/J/ApJS/80/137
- Title:
- Southern Extragalactic Radio Sources
- Short Name:
- J/ApJS/80/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains a list of 384 extragalactic radio sources south of declination -30{deg} which have been imaged with the Molonglo Observatory Synthesis Telescope (MOST) at 843 MHz with a HPBW of 44" x 44" cosec(dec). The sample includes those sources noted in the Molonglo Reference Catalog (MRC) (Cat.<VIII/16>) as extended (larger than 1'), as well as those noted as multiple (within 8' of another ssource and possibly related). The sample is representative of the strong extended extragalactic radio sources of the southern sky, but is not statistically complete. Positions, flux densities, and sizes are given for all sources, and those sources which have been confirmed as extended MRC sources are flagged. In addition, optical positions, magnitudes, redshifts, and identifications are given for 201 of the sources. These data were originally published in two tables which have been merged in this version.
