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Start Over Subject photometry Validation Level 2
801. BVRI light curves of 3 SN
ID:
ivo://CDS.VizieR/J/other/NewA/20.30
Title:
BVRI light curves of 3 SN
Short Name:
J/other/NewA/20.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate and densely populated BVRcIc lightcurves of supernovae SN 2011fe in M101, SN 2012aw in M95 and SN 2012cg in NGC 4424 are presented and discussed. The SN 2011fe lightcurves span a total range of 342 days, from 17 days pre- to 325 days post-maximum. The observations of both SN 2012aw and SN 2012cg were stopped by solar conjunction, when the objects were still bright. The lightcurve for SN 2012aw covers 92 days, that of SN 2012cg spans 44 days. Time and brightness of maxima are measured, and from the lightcurve shapes and decline rates the absolute magnitudes are obtained, and the derived distances are compared to that of the parent galaxies. The color evolution and the bolometric lightcurves are evaluated in comparison with those of other well observed supernovae, showing no significant deviations.
802. BVRI light curves of SN 2007gi
ID:
ivo://CDS.VizieR/J/PASP/122/1
Title:
BVRI light curves of SN 2007gi
Short Name:
J/PASP/122/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
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_exp_) approaching 15500km/s near-maximum brightness (compared to 10600km/s for SNe Ia with normal v_exp_). SN 2007gi reached a B-band peak magnitude of 13.25+/-0.04mag with a decline rate of {DELTA}m15(B)(true)=1.33+/-0.09mag. The B-band light curve of SN 2007gi demonstrated an interesting two-stage evolution during the nebular phase, with a decay rate of 1.16+/-0.05mag/(100days) during t=60-90days and 1.61+/-0.04mag/(100days) thereafter. Such behavior was also observed in the HV SN Ia 2006X, and might be caused by the interaction between supernova ejecta and circumstellar material (CSM) around HV SNe Ia. Based on a sample of a dozen well-observed R band (or unfiltered) light curves of SNe Ia, we confirm that the HV events may have a faster rise time to maximum than those with normal v_exp_.
803. BVRI light curves of SN 2003ie
ID:
ivo://CDS.VizieR/J/AJ/145/99
Title:
BVRI light curves of SN 2003ie
Short Name:
J/AJ/145/99
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new photometric observations of supernova (SN) 2003ie starting one month before discovery, obtained serendipitously while observing its host galaxy. With only a weak upper limit derived on the mass of its progenitor (<25M_{sun}_) from previous pre-explosion studies, this event could be a potential exception to the "red supergiant (RSG) problem" (the lack of high-mass RSGs exploding as Type IIP SNe). However, this is true only if SN2003ie was a Type IIP event, something which has never been determined. Using recently derived core-collapse SN light-curve templates, as well as by comparison to other known SNe, we find that SN2003ie was indeed a likely Type IIP event. However, with a plateau magnitude of ~-15.5mag, it is found to be a member of the faint Type IIP class. Previous members of this class have been shown to arise from relatively low-mass progenitors (<12M_{sun}_). It therefore seems unlikely that this SN had a massive RSG progenitor. The use of core-collapse SN light-curve templates is shown to be helpful in classifying SNe with sparse coverage. These templates are likely to become more robust as large homogeneous samples of core-collapse events are collected.
804. BVRI light curves of SN 2003jd
ID:
ivo://CDS.VizieR/J/MNRAS/383/1485
Title:
BVRI light curves of SN 2003jd
Short Name:
J/MNRAS/383/1485
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of a worldwide coordinated observational campaign on the broad-lined Type Ic supernova (SN Ic) 2003jd are presented. In total, 74 photometric data points and 26 spectra were collected using 11 different telescopes. SN 2003jd is one of the most luminous SN Ic ever observed. A comparison with other Type Ic supernovae (SNe Ic) confirms that SN 2003jd represents an intermediate case between broad-line events (2002ap, 2006aj) and highly energetic SNe (1997ef, 1998bw, 2003dh, 2003lw), with an ejected mass of M_ej_=3.0+/-1M_{sun}_ and a kinetic energy of E_k_(tot)=7^+3^_-2_x10^51^erg. SN 2003jd is similar to SN 1998bw in terms of overall luminosity, but it is closer to SNe 2006aj and 2002ap in terms of light-curve shape and spectral evolution. The comparison with other SNe Ic suggests that the V-band light curves of SNe Ic can be partially homogenized by introducing a time-stretch factor. Finally, because of the similarity of SN 2003jd to the SN 2006aj/XRF 060218 event, we discuss the possible connection of SN 2003jd with a gamma-ray burst (GRB).
805. BVRI light curves of some cool giant stars
ID:
ivo://CDS.VizieR/J/other/JAD/13.3
Title:
BVRI light curves of some cool giant stars
Short Name:
J/other/JAD/13.3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine Johnson BV and Cousins RI photometry of the cool giant stars HR 1105, HD 35155, HR 4088, TU CVn, IT Vir, and HR 7442, that the first author obtained with the Four College Automated Photoelectric Telescope. The new data for HR 1105 show that its variability is more complex than previously thought. Except a 0.3 phase gap in the photometry of HD 35155, the amplitude of variability is fairly constant. For HR 4088, except for one season, we did not find any periods shorter than 100 days. For the barium star IT Vir assuming the orbital period is the photometric period, the light curves consist of two similar subparts each one-half of the orbital period long. But there are problems with concluding that this star is an ellipsoidal variable. For HR 7442, more data is needed to derive an accurate period. A few observations are also presented of HR 1556, HR 363, HD 58521, and HD 49368.
806. BVRI light curves of the binary QS Vir
ID:
ivo://CDS.VizieR/J/AJ/157/3
Title:
BVRI light curves of the binary QS Vir
Short Name:
J/AJ/157/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We observed the post-common-envelope eclipsing binary with a white dwarf component, QS Vir, using the 1.88 m telescope of Kotammia Observatory in Egypt. The new observations were analyzed together with all multicolor light curves available online (sampling a period of 25 yr), using a full-feature binary system modeling software based on Roche geometry. This is the first time complete photometric modeling was done with most of these data. QS Vir is a detached system, with the red dwarf component underfilling its Roche lobe by a small margin. All light curves feature out-of-eclipse variability that is associated with ellipsoidal variation, mutual irradiation and irregularities in surface brightness of the tidally distorted and magnetically active red dwarf. We tested models with one, two, and three dark spots and found that one spot is sufficient to account for the light curve asymmetry in all data sets, although this does not rule out the presence of multiple spots. We also found that a single spotted model cannot fit light curves observed simultaneously in different filters. Instead, each filter requires a different spot configuration. To thoroughly explore the parameter space of spot locations, we devised a grid-search procedure and used it to find consistent solutions. Based on this, we conclude that the dark spot responsible for light curve distortions has been stable for the past 15 yr, after a major migration that happened between 1993 and 2002, possibly due to a flip-flop event.
807. BVRI light curves of the BL Lac object Mrk 501
ID:
ivo://CDS.VizieR/J/ApJ/849/161
Title:
BVRI light curves of the BL Lac object Mrk 501
Short Name:
J/ApJ/849/161
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present our observations of the optical intra-day variability (IDV) in {gamma}-ray BL Lac object Mrk 501. The observations were run with the 1.02m and 2.4m optical telescopes at Yunnan Observatories from 2005 April to 2012 May. The light curve at the R band on 2010 May 15 passes both variability tests (the F-test and the ANOVA test). A flare within the light curve on 2010 May 15 has a magnitude change of {Delta}m=0.03+/-0.005_stat_+/-0.007_sys_mag, a darkening timescale of {tau}_d_=26.7min., and an amplitude of IDV Amp=2.9%+/-0.7% . A decline described by 11 consecutive flux measurements within the flare can be fitted linearly with a Pearson's correlation coefficient r=0.945 at the confidence level of >99.99% . Under the assumptions that the IDV is tightly connected to the mass of the black hole, and that the flare duration, being two times {tau}_d_, is representative of the minimum characteristic timescale, we can derive upper bounds to the mass of the black hole. In the case of the Kerr black hole, the timescale of {Delta}t_min_^ob^=0.89hr gives M_{bullet}_<~10^9.20^M_{sun}_, which is consistent with measurements reported in the literature. This agreement indicates that the hypothesis about M_{bullet}_ and {Delta}t_min_^ob^ is consistent with the measurements/data.
808. BVRI light curves of the early-type binary V382 Cyg
ID:
ivo://CDS.VizieR/J/AJ/145/9
Title:
BVRI light curves of the early-type binary V382 Cyg
Short Name:
J/AJ/145/9
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze photometric and spectroscopic data and study the orbital period of the early-type interacting binary system V382 Cyg by using all the available data. We obtain a simultaneous light and radial velocity curve solution. The derived physical parameters of the primary and secondary stellar components are M_1_=27.9(5)M_{sun}_, M_2_=20.8(4)M_{sun}_, R_1_=9.7(2)R_{sun}_, R_2_=8.5(2)R_{sun}_, log(L_1_/L_{sun}_)=5.152(20), and log(L_2_/L_{sun}_)=4.954(19) while the separation of the components is a=23.4R_{sun}_. Newly obtained parameters yield the distance of the system to be 1466(76)pc. Analyses of the mid-eclipse times indicate a period increase of dP/dt=4.2(1)x10^-7^days/yr that can be interpreted in terms of the high-mass transfer (dM/dt=6.1(5)x10^-6^M_{sun}_/yr) from the less massive component to the more massive component. Finally, we model the evolution of the components using non-conservative codes and discuss the results obtained. The age of the binary system is estimated to be 3.85Myr.
809. BVRI light curves of type II-P supernovae
ID:
ivo://CDS.VizieR/J/MNRAS/442/844
Title:
BVRI light curves of type II-P supernovae
Short Name:
J/MNRAS/442/844
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study a sample of 23 Type II plateau supernovae (SNe II-P), all observed with the same set of instruments. Analysis of their photometric evolution confirms that their typical plateau duration is 100 d with little scatter, showing a tendency to get shorter for more energetic SNe. We examine the claimed correlation between the luminosity and the rise time from explosion to plateau. We analyse their spectra, measuring typical ejecta velocities, and confirm that they follow a well-behaved power-law decline. We find indications of high-velocity material in the spectra of six of our SNe. We test different dust-extinction correction methods by asking the following - does the uniformity of the sample increase after the application of a given method? A reasonably behaved underlying distribution should become tighter after correction. No method we tested made a significant improvement.
810. BVRI light curves of V374 Peg
ID:
ivo://CDS.VizieR/J/A+A/590/A11
Title:
BVRI light curves of V374 Peg
Short Name:
J/A+A/590/A11
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ultrafast-rotating (Prot~0.44d) fully convective single M4 dwarf V374 Peg is a well-known laboratory for studying intense stellar activity in a stable magnetic topology. As an observable proxy for the stellar magnetic field, we study the stability of the light curve, hence the spot configuration. We also measure the occurrence rate of flares and coronal mass ejections (CMEs). We have analysed spectroscopic observations, BV(RI)C photometry covering 5yrs, and additional RC photometry that expands the temporal base over 16yr. The light curve suggests an almost rigid-body rotation and a spot configuration that is stable over about 16 yrs, confirming the previous indications of a very stable magnetic field. We observed small changes on a nightly timescale and frequent flaring, including a possible sympathetic flare. The strongest flares seem to be more concentrated around the phase where the light curve indicates a smaller active region. Spectral data suggest a complex CME with falling-back and re-ejected material with a maximal projected velocity of ~675km/s. We observed a CME rate that is much lower than expected from extrapolations of the solar flare-CME relation to active stars.