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3101. RI-band LC of microlensing event OGLE-2018-BLG-1269Lb
ID:
ivo://CDS.VizieR/J/AJ/160/148
Title:
RI-band LC of microlensing event OGLE-2018-BLG-1269Lb
Short Name:
J/AJ/160/148
Date:
08 Dec 2021
Publisher:
CDS
Description:
We report the discovery of a planet in the microlensing event OGLE-2018-BLG-1269 with a planet-host mass ratio q~6x10^-4^, i.e., 0.6 times smaller than the Jupiter/Sun mass ratio. Combined with the Gaia parallax and proper motion, a strong one-dimensional constraint on the microlens parallax vector allows us to significantly reduce the uncertainties of lens physical parameters. A Bayesian analysis that ignores any information about light from the host yields that the planet is a cold giant (M_2_=0.69_-0.22_^+0.44^M_J_) orbiting a Sun-like star (M_1_=1.13_-0.35_^+0.72^M_{sun}_) at a distance of D_L_=2.56_-0.62_^+0.92^kpc. The projected planet-host separation is a_{perp}_=4.61_-1.17_^+1.70^au. Using Gaia astrometry, we show that the blended light lies <~12mas from the host and therefore must be either the host star or a stellar companion to the host. An isochrone analysis favors the former possibility at >99.6%. The host is therefore a subgiant. For host metallicities in the range of 0.0<=[Fe/H]<=+0.3, the host and planet masses are then in the range of 1.16<=M_1_/M_{sun}_<=1.38 and 0.74<=M_2_/M_J_<=0.89, respectively. Low host metallicities are excluded. The brightness and proximity of the lens make the event a strong candidate for spectroscopic follow-up both to test the microlensing solution and to further characterize the system.
3102. (RI)c photometry of variables in M31
ID:
ivo://CDS.VizieR/J/A+A/402/113
Title:
(RI)c photometry of variables in M31
Short Name:
J/A+A/402/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Cousins R and I band photometry of variable stars in a ~13'x13' region in the disk of M31 galaxy, obtained during 141 nights. Of the 26 Cepheid variables present in the region, two are newly discovered, 11 are classified as Cepheids for the first time and 13 are confirmed as Cepheids. The extensive photometry of these Cepheids enabled us to determine precise phase and amplitude of pulsation which ranges from 0.11 to 0.48mag in R band. The period of variability ranges from ~7.5 to 56 days. The period-luminosity diagram is used to derive a distance modulus of 24.49+/-0.11mag for M31 galaxy. We also report variability in 333 other stars, of them, 115 stars appear to be long period variables, 2 suspected eclipsing binaries and remaining 216 are irregular variables.
3103. RI differential photometry of CU Cnc
ID:
ivo://CDS.VizieR/J/A+A/398/239
Title:
RI differential photometry of CU Cnc
Short Name:
J/A+A/398/239
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric observations in the R and I bands of the detached M-type double-lined eclipsing binary CU Cnc have been acquired and analysed. The photometric elements obtained from the analysis of the light curves have been combined with an existing spectroscopic solution to yield high-precision (errors<2%) absolute dimensions: M_A_=0.4333+/-0.0017M_{sun}_, M_B_=0.3980+/-0.0014M_{sun}_, R_A_=0.4317+/-0.0052R_{sun}_, and R_B_=0.3908+/-0.0094R_{sun}_. The mean effective temperature of the system has been estimated to be Teff=3140+/-150K by comparing multi-band photometry with synthetic colors computed from model atmospheres. Additionally, we have been able to obtain an estimate for the age (~320Myr) and chemical composition ([Fe/H]~0.0) of the binary system through its membership of the Castor moving group.
3104. RIJHK photometry of VLM objects near eps Ori
ID:
ivo://CDS.VizieR/J/A+A/429/1007
Title:
RIJHK photometry of VLM objects near eps Ori
Short Name:
J/A+A/429/1007
Date:
21 Oct 2021
Publisher:
CDS
Description:
Coordinates and photometry of very low mass objects near epsilon Ori are presented. The RIJHK photometry of these objects is consistent with membership of the young Ori OB Ib association. Time series observations of this region were carried out using the ESO/MPG WFI at the 2.2-m telescope on La Silla, from 18 to 22 December 2001. In the framework of this monitoring campaign, we obtained deep Cousins R- and I-band images, from which we derived coordinates (columns 2 and 3) as well as photometry in the R- and I-band (columns 4 and 5). Additional near-infrared photometry in J, H, K comes from the 2MASS database (columns 6--8). The cluster member selection is based on a (I,R-I) colour magnitude diagram. The (J-H) colours were used to reject contaminating field stars. The masses given in column 9 were estimated by comparing the near-infrared photometry with the evolutionary tracks of Baraffe et al. (1998A&A...337..403B), assuming an age of 5Myr.
3105. RIJHKs of low-mass stars in sigma Ori
ID:
ivo://CDS.VizieR/J/AN/325/705
Title:
RIJHKs of low-mass stars in sigma Ori
Short Name:
J/AN/325/705
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an RI photometric survey covering an area of 430 arcmin^2^ around the multiple star sigma Orionis. The observations were conducted with the 0.8m IAC-80 Telescope at the Teide Observatory. The survey limiting R and I magnitudes are 22.5 and 21, and completeness magnitudes 21 and 20, respectively. We have selected 53 candidates from the I vs. R-I colour-magnitude diagram (I=14-20) that follow the previously known photometric sequence of the cluster. Adopting an age of 2-4 Myr for the cluster, we find that these objects span a mass range from 0.35M_{sun}_ to 0.015M_{sun}_. We have performed J-band photometry of 52 candidates and K_s photometry for 12 of them, with the result that 50 follow the expected infrared sequence for the cluster, thus confirming with great confidence that the majority of the candidates are bona fide members. JHK_s photometry from the Two Micron All Sky Survey (2MASS, Cat. <II/246>) is available for 50 of the candidates and are in good agreement with our data. Out of 48 candidates, which have photometric accuracies better than 0.1mag in all bands, only three appear to show near-infrared excesses.
3106. RIK photometry of far-IR sources in NGP
ID:
ivo://CDS.VizieR/J/MNRAS/401/1587
Title:
RIK photometry of far-IR sources in NGP
Short Name:
J/MNRAS/401/1587
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present follow-up observations of the far-infrared (FIR) sources at 90, 150 and 180um detected as part of the ISOPHOT EBL project, which has recently measured the absolute surface brightness of the cosmic infrared background (CIRB) radiation for the first time independently from COBE data. We have observed the fields at the North Galactic Pole region in the optical and near-IR, and complement these data with Sloan Digital Sky Survey photometry, and spectroscopy where available, and present identifications of the 25 FIR sources which reach down to ~150mJy in all three ISOPHOT bands. Identifications are done by means of full spectral energy density fitting to all sources in the FIR error circle areas.
3107. RI light curve of KELT-25 and KELT-26
ID:
ivo://CDS.VizieR/J/AJ/160/111
Title:
RI light curve of KELT-25 and KELT-26
Short Name:
J/AJ/160/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discoveries of KELT-25b (TIC 65412605, TOI-626.01) and KELT-26b (TIC 160708862, TOI-1337.01), two transiting companions orbiting relatively bright, early A stars. The transit signals were initially detected by the KELT survey and subsequently confirmed by Transiting Exoplanet Survey Satellite (TESS) photometry. KELT-25b is on a 4.40day orbit around the V=9.66 star CD-245016 (Teff=8280_-180_^+440^K, M{star}=2.18_-0.11_^+0.12^M{sun}), while KELT-26b is on a 3.34day orbit around the V=9.95 star HD134004 (Teff=8640_-240_^+500^K, M{star}=1.93_-0.16_^+0.14^M{sun}), which is likely an Am star. We have confirmed the substellar nature of both companions through detailed characterization of each system using ground-based and TESS photometry, radial velocity measurements, Doppler tomography, and high-resolution imaging. For KELT-25, we determine a companion radius of RP=1.64_-0.043_^+0.039^RJ and a 3{sigma} upper limit on the companion's mass of ~64MJ. For KELT-26b, we infer a planetary mass and radius of MP=1.41_-0.51_^+0.43^M_J_ and RP=1.94_-0.058_^+0.060^RJ. From Doppler tomographic observations, we find KELT-26b to reside in a highly misaligned orbit. This conclusion is weakly corroborated by a subtle asymmetry in the transit light curve from the TESS data. KELT-25b appears to be in a well-aligned, prograde orbit, and the system is likely a member of the cluster Theia449.
3108. RI light curves of the type IIn SN 2009ip
ID:
ivo://CDS.VizieR/J/ApJ/763/L27
Title:
RI light curves of the type IIn SN 2009ip
Short Name:
J/ApJ/763/L27
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent observations by Mauerhan et al. (2013MNRAS.430.1801M) have shown the unprecedented transition of the previously identified luminous blue variable (LBV) and supernova (SN) impostor SN 2009ip to a real Type IIn SN explosion. We present ~100 optical R- and I-band photometric measurements of SN 2009ip obtained between UT 2012 September 23.6 and October 9.6, using 0.3-0.4m aperture telescopes from the Coral Towers Observatory in Cairns, Australia. The light curves show well-defined phases, including very rapid brightening early on (0.5mag in 6hr observed during the night of September 24), a transition to a much slower rise between September 25 and September 28, and a plateau/peak around October 7. These changes are coincident with the reported spectroscopic changes that most likely mark the start of a strong interaction between the fast SN ejecta and a dense circumstellar medium formed during the LBV eruptions observed in recent years. In the 16-day observing period, SN 2009ip brightened by 3.7mag from I=17.4mag on September 23.6 (M_I_=~-14.2) to I=13.7mag (M_I_=~-17.9) on October 9.6, radiating ~3x10^49^erg in the optical wavelength range. As of 2012 October 9.6, SN 2009ip is more luminous than most Type IIP SN and comparable to other Type IIn SN.
3109. RI photometry in alpha Per and Pleiades
ID:
ivo://CDS.VizieR/J/A+A/416/125
Title:
RI photometry in alpha Per and Pleiades
Short Name:
J/A+A/416/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photographic astrometry (proper motions and accurate positions), photometry (in the photographic R and I passbands) and membership probabilities for high probability proper motion members of the clusters Alpha Persei and The Pleiades are presented, along with cross-identifications with names from previously known members in the compilation of Prosser & Stauffer (The Stauffer & Prosser Open Cluster Catalogue, priv.comm.) and their corresponding proper motion membership probabilities according to our study. The SuperCOSMOS facility at the Royal Observatory Edinburgh has (using plates from the United Kingdom Schmidt Telescope) produced complete southern sky surveys in BJ, R and I with an additional second epoch R survey. These surveys are now publicly available (Hambly et al. 2001MNRAS.326.1279H). The scanning program has now moved on to the northern hemisphere, using film and glass copies of plates taken by the Oschin Schmidt Telescope on Mount Palomar, California. These data will soon be publicly available.
3110. RI photometry of blazars S5 0716+714 and 3C 273
ID:
ivo://CDS.VizieR/J/ApJ/880/155
Title:
RI photometry of blazars S5 0716+714 and 3C 273
Short Name:
J/ApJ/880/155
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the photometric observations of blazars S5 0716+714 and 3C 273 with high temporal resolution (30-60s) in the I or R bands. The observations were performed with a 1.02m optical telescope from 2007 March 7 to 2012 May 16. The F-test, one-way analysis of variance (ANOVA) test, and z-transformed discrete correlation function (ZDCF) cross-correlation zero lag test are used to search for intra-day variability (IDV). Four and five reliable IDVs survive three tests for S5 0716+714 and 3C 273, respectively. IDVs are found for S5 0716+714 and 3C 273. A flare on 2008 May 8 has {Delta}I~0.06+/-0.01mag in a duration of 0.54hr for S5 0716+714. A flare on 2011 May 10 shows {Delta}R~0.05+/-0.01mag in a duration of 0.40hr for 3C 273. Sharp dips appear on 2011 May 9 for 3C 273 and show {Delta}R~0.05+/-0.01mag. Under the assumptions that the IDV is tightly connected to black hole mass, M*, and that the flare durations are representative of the minimum characteristic timescales, we can estimate upper bounds to M*. In the case of the Kerr black holes, M*<~10^8.91^M_{sun}_ and M*<~10^9.02^M_{sun}_ are given for S5 0716+714 and 3C 273, respectively. These mass measurements are consistent with those measurements reported in the literature. Also, we discuss the origins of optical variations found in this work.