- ID:
- ivo://CDS.VizieR/J/ApJ/893/143
- Title:
- UBVRIJHK & spec. obs. of type Ia SN2019ein
- Short Name:
- J/ApJ/893/143
- Date:
- 07 Mar 2022 07:30:20
- Publisher:
- CDS
- Description:
- We present optical observations of the Type Ia supernova (SN) 2019ein, starting two days after the estimated explosion date. The spectra and light curves show that SN 2019ein belongs to a high-velocity (HV) and broad-line group with a relatively rapid decline in the light curves ({Delta}m_15_(B)=1.36+/-0.02mag) and a short rise time (15.37+/-0.55days). The SiII{lambda}6355 velocity, associated with a photospheric component but not with a detached high-velocity feature, reached ~20000km/s 12 days before the B-band maximum. The line velocity, however, decreased very rapidly and smoothly toward maximum light, to ~13000km/s, which is relatively low among HV SNe. This indicates that the speed of the spectral evolution of HV SNe Ia is correlated with not only the velocity at maximum light, but also the light-curve decline rate, as is the case for normal-velocity (NV) SNeIa. Spectral synthesis modeling shows that the outermost layer at >17000km/s is well described by an O-Ne-C burning layer extending to at least 25000km/s, and there is no unburnt carbon below 30000km/s; these properties are largely consistent with the delayed detonation scenario and are shared with the prototypical HV SN 2002bo despite the large difference in {Delta}m_15_(B). This structure is strikingly different from that derived for the well-studied NV SN 2011fe. We suggest that the relation between the mass of ^56^Ni (or {Delta}m_15_) and the extent of the O-Ne-C burning layer provides an important constraint on the explosion mechanism(s) of HV and NV SNe.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/428/555
- Title:
- UBVRIJHKs photometry of 2000cx
- Short Name:
- J/A+A/428/555
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a systematic and comprehensive monitoring programme of the type Ia supernova 2000cx at late phases using the VLT and HST. The VLT observations cover phases 360 to 480 days past maximum brightness and include photometry in the BVRIJH bands, together with a single epoch in each of U and Ks.
- ID:
- ivo://CDS.VizieR/II/7A
- Title:
- UBVRIJKLMNH Photoelectric Catalogue
- Short Name:
- II/7A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains the results from star brightness measures in the first ten (UBVRIJKLMN) broad wavelength bands (Johnson 1965) and the additional bandpass H (Johnson et al. 1968). Data in the above system that have been published up to June 1977 are included. The source reference (Morel and Magnenat 1978) states that there are 5943 entries in the data set with data for 4494 stars. However, a count of the records by coded number shows that there are only 4486 unique entries (not 4494). The catalog includes coded identification numbers (Geneva system), 11 magnitudes, numbers of measurements in each filter, and references.
- ID:
- ivo://CDS.VizieR/J/A+A/349/619
- Title:
- UBVRI light curves of AA Tau in 1995
- Short Name:
- J/A+A/349/619
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have monitored the photometric, spectroscopic and polarimetric variations of the classical T Tauri star (CTTS) AA Tau over a period of a month. The light curve consists of more than 260 measurements in each of the B and V-bands over a continuous time period of 30 days and more than 180 measurements in the R and I-bands. This provides unprecedented detail of the photometric variations of a CTTS on timescales ranging from hours to weeks.
- ID:
- ivo://CDS.VizieR/J/A+A/409/169
- Title:
- UBVRI light curves of AA Tau in 1999
- Short Name:
- J/A+A/409/169
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a synoptic study of the photometric and spectroscopic variability of the classical T Tauri star AA Tau on timescales ranging from a few hours to several weeks. The AA Tau light curve had been previously shown to vary with a 8.2d period, exhibiting a roughly constant brightness level, interrupted by quasi-cyclic fading episodes, which we interpreted as recurrent eclipses of the central star by the warped inner edge of its accretion disk (Bouvier et al. 1999, Cat. <J/A+A/349/619>). Our observations show the system is dynamic and presents non-stationary variability both in the photometry and spectroscopy.
- ID:
- ivo://CDS.VizieR/J/other/CoSka/42.39
- Title:
- UBVRI light curves of Dwarf nova Peg 2010
- Short Name:
- J/other/CoSka/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present our UBVRcIc CCD photometry of a new dwarf nova OT J213806.6+261957 in Pegasus, discovered during its superoutburst on May 6, 2010 and classified as a WZ Sge-type star. In the term May 15 - November 27, 2010, we obtained more than 10000 CCD observations of the nova. Twocolour diagrams together with the superoutburst evolutionary tracks of the nova are presented. The analysis of our data revealed the presence of ordinary superhumps with the mean period of 0.055106d and late superhumps with the period of 0.05490d. We calculated the orbital period of the dwarf nova Pegasi 2010 to be 0.0542+/-0.005d and estimated the mass of the red dwarf component in the binary as 0.09+/-0.01M_{sun}.
- ID:
- ivo://CDS.VizieR/J/AZh/88/894
- Title:
- UBVRI light curves of EQ Boo
- Short Name:
- J/AZh/88/894
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first estimates of the relative and absolute parameters of the eclipsing binary EQ Boo based on a light-curve analysis (P=5.43d, V=8.8m). This star is simultaneously Component A of the visual binary ADS 9422 (spectral types F7V + G0V; separation of the components 1.3"; magnitude difference 0.7m). The derived disagreement between the components' physical parameters and the assumption that they have the same age can be removed if there is a fourth, late-type star in the system. This is also able to explain the observed anomaly in the behavior of the O-C residuals at times of minima.
- ID:
- ivo://CDS.VizieR/J/A+A/415/289
- Title:
- UBVRI light curves of ER Vul
- Short Name:
- J/A+A/415/289
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New photoelectric UBV and BVRI observations, secured during August-November of 2002 at two observatories distant in local time are analyzed together with two earlier photometric data sets and all available radial velocities to derive the most accurate ephemeris of the binary and to set limits on its basic physical elements. These observations were obtained as a support for a high-dispersion spectroscopic study, results of which will be published separately. It was found that radial velocities and photometric observations spanning 53 years can be reconciled with the linear ephemeris T_(prim.min.)_=HJD 2440182.25628(46) + 0.698095113(29)days x E, where the rms errors of the last digits are given in brackets. Masses of the stars are 1.02 and 0.97 solar masses and the binary separation is 4.170 solar radii. There is still a large uncertainty in the stellar radii. We also report the discovery of rapid light variations on a time scale of hours seen in the U band light curve and offer a few thoughts on the future investigation of this binary.
- ID:
- ivo://CDS.VizieR/J/AJ/149/90
- Title:
- UBVRI light curves of GSC 3208-1986
- Short Name:
- J/AJ/149/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- GSC 3208 1986 is an NSVS and TYCHO binary, first observed from 1999 to 2000. It is a W UMa binary with a period of 0.405days. The present observations were taken in 2012 September and are of high precision, averaging a standard deviation of better than 5mmag. The amplitude of the light curve is very nearly 0.5mag yet it undergoes total eclipses. Dominion Astrophysical Observatory spectra give an F3V type (T~6900K) for the system, the earliest of the extreme mass ratio W UMa binaries. The linear period determination of 0.4045672days was calculated with the two sets of epochs available. An early NSVS light curve reveals that the period has been smoothly decreasing over its past 12000 orbits. The binary may be undergoing sinusoidal oscillations due to the presence of a third body, possibly with a period of 23+/-3years. The high inclination of 85{deg} results in a long duration secondary total eclipse, lasting some 49.5minutes. Findings indicate that GSC 3208 1986 is an immaculate extreme mass ratio, q(m_2_/m_1_)=0.24, A-type W UMa binary.
- ID:
- ivo://CDS.VizieR/J/MNRAS/385/823
- Title:
- UBVRI light curves of OJ 287
- Short Name:
- J/MNRAS/385/823
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on the long-term data in the literature, we present evidence for long-term optical spectral index variability behaviour for BL Lacertae object OJ 287. First we find that the optical spectral index variability period of BL Lacertae object OJ 287 is in agreement with the optical flux variability period of about 11.96yr. It is considered that different processes induce optical variability, and each process should have a definite signature in the spectral index, thus leading to the periodicity of the spectral index. We also find that the time lag between the optical spectral index and the optical flux density is half of the optical flux variability period. This result tends to support the argument that when the brightness of the long-term variations increases, the optical spectra become bluer. These variations can be explained by energy loss of the electrons during the outburst. We show that the spectral index is different during the flares compared with outside the flares; between the first and second flare peaks of the superflares, the spectrum shapes are different. Disparate processes possibly induce the two peaks of OJ 287.
