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5131. Photometry of RR Lyrae candidates in Virgo stream
ID:
ivo://CDS.VizieR/J/ApJ/691/306
Title:
Photometry of RR Lyrae candidates in Virgo stream
Short Name:
J/ApJ/691/306
Date:
21 Oct 2021
Publisher:
CDS
Description:
A subset of the RR Lyrae (RRL) candidates identified from the Southern Edgeworth-Kuiper Belt Object (SEKBO) survey data have been followed up photometrically (n=106) and spectroscopically (n=51). Period and light curve fitting reveals a 24+/-7% contamination of SEKBO survey data by non-RRLs. This paper focuses on the region of the Virgo Stellar Stream (VSS), particularly on its extension to the south of the declination limits of the Sloan Digital Sky Survey and of the Quasar Equatorial Survey Team (QUEST) RRL survey.
5132. Photometry of RR Lyr stars in LMC cluster NGC 1835
ID:
ivo://CDS.VizieR/J/AJ/105/527
Title:
Photometry of RR Lyr stars in LMC cluster NGC 1835
Short Name:
J/AJ/105/527
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometry is presented for the RR Lyrae variables in the Large Magellanic Cloud (LMC) cluster NGC 1835. Sixteen new variables have been discovered. Due to the extreme crowding of the LMC field stars, the scatter of the light curves and mean magnitudes is greater than that found for other LMC clusters studied under similar conditions. The derived parameters of the light curves yield E(B-V) = 0.13 and [Fe/H] = -1.8, consistent with previous measurements. The complete sample of RR Lyraes has mean magnitudes <V> = 19.38, <B> = 19.70. If a distance modulus of 18.5 mag for the LMC is assumed, then in the mean the NGC 1835 RR Lyraes have <Mv> = 0.48, almost identical to the average found by the same procedure for the six other LMC clusters.
5133. Photometry of S5 0716+714
ID:
ivo://CDS.VizieR/J/AJ/129/1818
Title:
Photometry of S5 0716+714
Short Name:
J/AJ/129/1818
Date:
21 Oct 2021
Publisher:
CDS
Description:
Optical monitoring of S5 0716+714 was performed with a 60/90 Schmidt telescope in 2003 November and December and 2004 January for studying the variability of the object on short timescales. Because of the high brightness of the source, we could carry out quasi-simultaneous measurements in three bands with a temporal resolution of about 20min by using one single telescope.
5134. Photometry of SDSS J152419.33+220920.0
ID:
ivo://CDS.VizieR/J/A+A/554/A25
Title:
Photometry of SDSS J152419.33+220920.0
Short Name:
J/A+A/554/A25
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new photometry of the faint (g~19mag) and poorly studied cataclysmic variable SDSS J152419.33+220920.0, analyze its light curve and provide an accurate ephemeris for this system. Time-resolved CCD differential photometry was carried out using the 1.5m and 0.84m telescopes at the Observatorio Astronomico Nacional at San Pedro Martir. All observations were taken in white-light (no filter). This table contains the differential photometry for the system obtained during six nights (covering more than twenty primary eclipse cycles in more than three years). The reference for the photometry is SDSS J152415.99+220804.0, g=17.77 (marked as star C1 in the paper). The associated errors are 0.02mag outside eclipse. The information for each observation run is presented in Table 1 and the light-curves using this data are presented in Figure 4. Our light curve analysis shows that only two fundamental frequencies are present, corresponding to the orbital period and a modulation with twice this frequency. We determine the accurate ephemeris of the system to be HJD_eclipse_=2454967.6750(1)+0.06531866661(1)E. A double-hump orbital period modulation, a standing feature in several bounce-back systems at quiescence, is present at several epochs. However, we found no other evidence to support the hypothesis that this system belongs to the post-minimum orbital-period systems.
5135. Photometry of SN 2009bb
ID:
ivo://CDS.VizieR/J/ApJ/728/14
Title:
Photometry of SN 2009bb
Short Name:
J/ApJ/728/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudobolometric light curve of SN 2009bb suggests that 4.1+/-1.9M_{sun}_ of material was ejected with 0.22+/-0.06M_{sun} of it being ^56^Ni. The resulting kinetic energy is 1.8+/-0.7x10^52^erg. This, together with an absolute peak magnitude of M_B_=-18.36+/-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for gamma-ray bursts (GRBs), we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of {gamma}-ray instruments.
5136. Photometry of SN 2003cg
ID:
ivo://CDS.VizieR/J/MNRAS/369/1880
Title:
Photometry of SN 2003cg
Short Name:
J/MNRAS/369/1880
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical and near-infrared photometry and spectroscopy of the Type Ia SN 2003cg, which exploded in the nearby galaxy NGC 3169. The observations cover a period between 8.5 and +414d post-maximum. SN 2003cg is a normal but highly reddened Type Ia event. Its B magnitude at maximum Bmax=15.94+/-0.04 and {Delta}m15(B)_obs_=1.12+/-0.04 [{Delta}m15(B)_intrinsic_=1.25+/-0.05]. Allowing RV to become a free parameter within the Cardelli et al. (1989ApJ...345..245C) extinction law, simultaneous matches to a range of colour curves of normal SNe Ia yielded E(B-V)=1.33+/-0.11, and RV=1.80+/-0.19. While the value obtained for RV is small, such values have been invoked in the past, and may imply a grain size which is small compared with the average value for the local interstellar medium.
5137. Photometry of SN 2008D
ID:
ivo://CDS.VizieR/J/ApJ/692/L84
Title:
Photometry of SN 2008D
Short Name:
J/ApJ/692/L84
Date:
21 Oct 2021
Publisher:
CDS
Description:
On 2008 January 9.56 UT, SN 2008D was discovered while following up an unusually bright X-ray transient (XT) in the nearby spiral galaxy NGC 2770. We present early optical spectra (obtained 1.75 days after the XT) which allowed the first identification of the object as a supernova (SN) at redshift z=0.007. These spectra were acquired during the initial declining phase of the light curve, likely produced in the stellar envelope cooling after shock breakout, and rarely observed. They exhibit a rather flat spectral energy distribution with broad undulations, and a strong, W-shaped feature with minima at 3980 and 4190{AA} (rest frame). We also present extensive spectroscopy and photometry of the SN during the subsequent photospheric phase. Unlike SNe associated with gamma-ray bursts, SN 2008D displayed prominent He features and is therefore of Type Ib.
5138. Photometry of SN 2015da
ID:
ivo://CDS.VizieR/J/A+A/635/A39
Title:
Photometry of SN 2015da
Short Name:
J/A+A/635/A39
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we report the results of the first ~four years of spectroscopic and photometric monitoring of the Type IIn supernova SN 2015da (also known as PSN J13522411+3941286, or iPTF16tu). The supernova exploded in the nearby spiral galaxy NGC 5337 in a relatively highly extinguished environment. The transient showed prominent narrow Balmer lines in emission at all times and a slow rise to maximum in all bands. In addition, early observations performed by amateur astronomers give a very well-constrained explosion epoch. The observables are consistent with continuous interaction between the supernova ejecta and a dense and extended H-rich circumstellar medium. The presence of such an extended and dense medium is difficult to reconcile with standard stellar evolution models, since the metallicity at the position of SN 2015da seems to be slightly subsolar. Interaction is likely the mechanism powering the light curve, as confirmed by the analysis of the pseudo bolometric light curve, which gives a total radiated energy >~10^51^erg. Modeling the light curve in the context of a supernova shock breakout through a dense circumstellar medium allowed us to infer the mass of the prexisting gas to be ~=8M_{sun}_, with an extreme mass-loss rate for the progenitor star ~=0.6M_{sun}_/yr, suggesting that most of the circumstellar gas was produced during multiple eruptive events. Near- and mid-infrared observations reveal a fluxexcess in these domains, similar to those observed in SN 2010jl and other interacting transients, likely due to preexisting radiatively heated dust surrounding the supernova. By modeling the infrared excess, we infer a mass >~0.4x10^-3^M_{sun}_ for the dust.
5139. Photometry of SN 2013gh and iPTF13dge
ID:
ivo://CDS.VizieR/J/A+A/592/A40
Title:
Photometry of SN 2013gh and iPTF13dge
Short Name:
J/A+A/592/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
Temporal variability of narrow absorption lines in high-resolution spectra of Type Ia supernovae (SNe Ia) is studied to search for circumstellar matter. Time series which resolve the profiles of absorption lines such as NaI D or CaII H&K are expected to reveal variations due to photoionisation and subsequent recombination of the gases. The presence, composition, and geometry of circumstellar matter may hint at the elusive progenitor system of SNe Ia and could also affect the observed reddening law. To date, there are few known cases of time-varying NaI D absorption in SNe Ia, all of which occurred during relatively late phases of the supernova (SN) evolution. Photoionisation, however, is predicted to occur during the early phases of SNe Ia, when the supernovae peak in the ultraviolet. We attempt, therefore, to observe early-time absorption-line variations by obtaining high-resolution spectra of SNe before maximum light We have obtained photometry and high-resolution spectroscopy of SNe Ia 2013gh and iPTF 13dge, to search for absorption- line variations. Furthermore, we study interstellar absorption features in relation to the observed photometric colours of the SNe. Results. Both SNe display deep NaI D and CaII H&K absorption features. Furthermore, small but significant variations are detected in a feature of the NaI D profile of SN 2013gh. The variations are consistent with either geometric effects of rapidly moving or patchy gas clouds or photoionisation of NaI gas at R~=10^19^cm from the explosion. Our analysis indicates that it is necessary to focus on early phases to detect photoionisation effects of gases in the circumstellar medium of SNe Ia. Different absorbers such as NaI and CaII can be used to probe for matter at different distances from the SNe. The nondetection of variations during early phases makes it possible to put limits on the abundance of the species at those distances.
5140. Photometry of sources in IRAS 16362-4845 cluster
ID:
ivo://CDS.VizieR/J/A+A/473/149
Title:
Photometry of sources in IRAS 16362-4845 cluster
Short Name:
J/A+A/473/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
The IRAS 16362-4845 star-forming site in the RCW 108 complex contains an embedded compact cluster that includes some massive O-type stars. Star formation in the complex, and in particular in IRAS 16362-4845, has been proposed to be externally triggered by the action of NGC 6193. We present a photometric study of the IRAS 16362-4845 cluster sensitive enough to probe the massive brown dwarf regime. In particular, we try to verify an apparent scarcity of solar-type and low-mass stars reported in a previous paper (Comeron et al., 2005A&A...433..955C).