- ID:
- ivo://CDS.VizieR/J/ApJ/809/59
- Title:
- Ophiuchus stellar stream with PS1 data
- Short Name:
- J/ApJ/809/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Ophiuchus stream is a recently discovered stellar tidal stream in the Milky Way. We present high-quality spectroscopic data for 14 stream member stars obtained using the Keck and MMT telescopes. We confirm the stream as a fast moving (v_los_~290km/s), kinematically cold group ({sigma}_{nu}_los__<~1km/s) of {alpha}-enhanced and metal-poor stars ([{alpha}/Fe]~0.4dex, [Fe/H]~-2.0dex). Using a probabilistic technique, we model the stream simultaneously in line-of-sight velocity, color-magnitude, coordinate, and proper motion space, and so determine its distribution in 6D phase-space. We find that the stream extends in distance from 7.5 to 9kpc from the Sun; it is 50 times longer than wide, merely appearing highly foreshortened in projection. The analysis of the stellar population contained in the stream suggests that it is ~12Gyr old, and that its initial stellar mass was ~2x10^4^M_{sun}_ (or at least >~7x10^3^M_{sun}_). Assuming a fiducial Milky Way potential, we fit an orbit to the stream that matches the observed phase-space distribution, except for some tension in the proper motions: the stream has an orbital period of ~350Myr, and is on a fairly eccentric orbit (e~0.66) with a pericenter of ~3.5kpc and an apocenter of ~17kpc. The phase-space structure and stellar population of the stream show that its progenitor must have been a globular cluster that was disrupted only ~240Myr ago. We do not detect any significant overdensity of stars along the stream that would indicate the presence of a progenitor, and conclude that the stream is all that is left of the progenitor.
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- ID:
- ivo://CDS.VizieR/J/AJ/159/153
- Title:
- Optical and IR photometry in the HII region Sh2-242
- Short Name:
- J/AJ/159/153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here identification and characterization of the young stellar population associated with an active star-forming site Sh2-242. We used our own new optical imaging and spectroscopic observational data, as well as several archival catalogs, e.g., Pan-STARRS-1, Gaia-DR2, Isaac Newton Telescope Photometric H-Alpha Survey (IPHAS), Wide-field InfraRed Camera, 2MASS, and Spitzer. Slit spectroscopic results confirm the classification of the main ionizing source BD+26980 as an early-type star of spectral type B0.5V. The spectrophotometric distance of the star is estimated as 2.08{+/-}0.24kpc, which confirms the source as a member of the cluster. An extinction map covering a large area (diameter ~50') is generated with H and K photometry toward the region. From the map, three distinct locations of peak extinction complexes (A_V_~7-17mag) are identified for the very first time. Using the infrared color excess, a total of 33 Class I and 137 Class II young objects are classified within the region. The IPHAS photometry reveals classification of 36 H{alpha} emitting sources, which might be class II objects. Among 36 H{alpha} emitting sources, 5 are already identified using infrared excess emission. In total, 201 young objects are classified toward S242 from this study. The membership status of the young sources is further windowed with the inclusion of parallax from the Gaia DR2 catalog. Using the optical and infrared color-magnitude diagrams, the young stellar objects are characterized with an average age of ~1Myr and masses in the range 0.1-3.0M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/AJ/160/74
- Title:
- Optical and IR photometry of OGLE-2017-BLG-0406
- Short Name:
- J/AJ/160/74
- Date:
- 10 Dec 2021
- Publisher:
- CDS
- Description:
- We report the discovery and analysis of the planetary microlensing event OGLE-2017-BLG-0406, which was observed both from the ground and by the Spitzer satellite in a solar orbit. At high magnification, the anomaly in the light curve was densely observed by ground-based-survey and follow-up groups, and it was found to be explained by a planetary lens with a planet/host mass ratio of q=7.0x10^-4^ from the light-curve modeling. The ground-only and Spitzer-"only" data each provide very strong one-dimensional (1D) constraints on the 2D microlens parallax vector {pi}_E_. When combined, these yield a precise measurement of {pi}_E_ and of the masses of the host M_host_=0.56{+/-}0.07M_{sun} and planet M_planet_=0.41{+/-}0.05M_Jup_. The system lies at a distance D_L_=5.2{+/-}0.5 kpc from the Sun toward the Galactic bulge, and the host is more likely to be a disk population star according to the kinematics of the lens. The projected separation of the planet from the host is a_{perp}_=3.5{+/-}0.3au (i.e., just over twice the snow line). The Galactic-disk kinematics are established in part from a precise measurement of the source proper motion based on OGLE-IV data. By contrast, the Gaia proper-motion measurement of the source suffers from a catastrophic 10{sigma} error.
- ID:
- ivo://CDS.VizieR/J/ApJS/213/19
- Title:
- Optical and near-IR light curves of 64 SNe
- Short Name:
- J/ApJS/213/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a densely sampled, homogeneous set of light curves of 64 low-redshift (z<~0.05) stripped-envelope supernovae (SNe of Type IIb, Ib, Ic, and Ic-BL). These data were obtained between 2001 and 2009 at the Fred L. Whipple Observatory (FLWO) on Mount Hopkins in Arizona, with the optical FLWO 1.2m and the near-infrared (NIR) Peters Automated Infrared 1.3m telescopes. Our data set consists of 4543 optical photometric measurements on 61 SNe, including a combination of UBVRI, UBVr'i', and u'BVr'i', and 1919 JHK_s_ NIR measurements on 25 SNe. This sample constitutes the most extensive multi-color data set of stripped-envelope SNe to date. Our photometry is based on template-subtracted images to eliminate any potential host-galaxy light contamination. This work presents these photometric data, compares them with data in the literature, and estimates basic statistical quantities: date of maximum, color, and photometric properties. We identify promising color trends that may permit the identification of stripped-envelope SN subtypes from their photometry alone. Many of these SNe were observed spectroscopically by the Harvard-Smithsonian Center for Astrophysics (CfA) SN group, and the spectra are presented in a companion paper. A thorough exploration that combines the CfA photometry and spectroscopy of stripped-envelope core-collapse SNe will be presented in a follow-up paper.
- ID:
- ivo://CDS.VizieR/J/ApJ/863/90
- Title:
- Optical and NIR LCs of the nearby SN 2017cbv
- Short Name:
- J/ApJ/863/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On 2017 March 11, the DLT40 Transient Discovery Survey discovered SN2017cbv in NGC 5643, a Type 2 Seyfert Galaxy in the Lupus Constellation. SN 2017cbv went on to become a bright Type Ia supernova, with a Vmax of 11.51+/-0.05mag. We present early time optical and infrared photometry of SN 2017cbv covering the rise and fall of over 68 days. We find that SN 2017cbv has a broad light curve {Delta}m_15_(B)=0.88+/-0.07, a B-band maximum at 2457840.97+/-0.43, a negligible host galaxy reddening where E(B-V)_host_~0, and a distance modulus of 30.49+/-0.32 to the SN, corresponding to a distance of 12.58_-1.71_^+1.98^Mpc. We also present the results of two different numerical models we used for analysis in this paper: SALT2, an empirical model for Type Ia supernova optical light curves that accounts for variability components; and SNooPy, the CSP-II light-curve model that covers both optical and near-infrared wavelengths and is used for distance estimates.
- ID:
- ivo://CDS.VizieR/J/ApJ/904/14
- Title:
- Optical and NIR observation of SN (Ia) 2017cbv
- Short Name:
- J/ApJ/904/14
- Date:
- 24 Mar 2022 06:19:55
- Publisher:
- CDS
- Description:
- Supernova (SN) 2017cbv in NGC5643 is one of a handful of Type Ia supernovae (SNeIa) reported to have excess blue emission at early times. This paper presents extensive BVRIYJHKs-band light curves of SN2017cbv, covering the phase from -16 to +125days relative to B-band maximum light. The SN2017cbv reached a B-band maximum of 11.710{+/-}0.006mag, with a postmaximum magnitude decline of {Delta}m15(B)=0.990{+/-}0.013mag. The SN suffered no host reddening based on Phillips intrinsic color, the Lira-Phillips relation, and the CMAGIC diagram. By employing the CMAGIC distance modulus {mu}=30.58{+/-}0.05mag and assuming H0=72km/s/Mpc, we found that 0.73M{sun} 56Ni was synthesized during the explosion of SN2017cbv, which is consistent with estimates using reddening- and distance-free methods via the phases of the secondary maximum of the near-IR- (NIR-) band light curves. We also present 14 NIR spectra from -18 to +49 days relative to the B-band maximum light, providing constraints on the amount of swept-up hydrogen from the companion star in the context of the single degenerate progenitor scenario. No Pa{beta} emission feature was detected from our postmaximum NIR spectra, placing a hydrogen mass upper limit of 0.1M{sun}. The overall optical/NIR photometric and NIR spectral evolution of SN2017cbv is similar to that of a normal SN Ia, even though its early evolution is marked by a flux excess not seen in most other well-observed normal SNe Ia. We also compare the exquisite light curves of SN2017cbv with some Mch delayed detonation models and sub-Mch double detonation models.
- ID:
- ivo://CDS.VizieR/J/ApJ/895/118
- Title:
- Optical and NIR photometry of 2 Ia type supernovae
- Short Name:
- J/ApJ/895/118
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present photometric and spectroscopic observations of SN2013aa and SN2017cbv, two nearly identical type Ia supernovae (SNeIa) in the host galaxy NGC5643. The optical photometry has been obtained using the same telescope and instruments used by the Carnegie Supernova Project. This eliminates most instrumental systematics and provides light curves in a stable and well-understood photometric system. Having the same host galaxy also eliminates systematics due to distance and peculiar velocity, providing an opportunity to directly test the relative precision of SNeIa as standard candles. The two SNe have nearly identical decline rates, negligible reddenings, and remarkably similar spectra, and, at a distance of ~20Mpc, they are ideal potential calibrators for the absolute distance using primary indicators such as Cepheid variables. We discuss to what extent these two SNe can be considered twins and compare them with other supernova "siblings" in the literature and their likely progenitor scenarios. Using 12 galaxies that hosted two or more SNe Ia, we find that when using SNeIa, and after accounting for all sources of observational error, one gets consistency in distance to 3%.
- ID:
- ivo://CDS.VizieR/J/AJ/148/1
- Title:
- Optical and ultraviolet photometry of SN 2012fr
- Short Name:
- J/AJ/148/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extensive optical and UltraViolet (UV) observations of the type Ia supernova (SN Ia) 2012fr are presented in this paper. It has a relatively high luminosity, with an absolute B-band peak magnitude of about -19.5mag and a smaller post-maximum decline rate than normal SNe Ia (e.g., {Delta}m_15_(B)=0.85+/-0.05mag). Based on the UV and optical light curves, we derived that a ^56^Ni mass of about 0.88M_{sun}_ was synthesized in the explosion. The earlier spectra are characterized by noticeable high-velocity features of Si II {lambda}6355 and Ca II with velocities in the range of ~22000-25000km/s. At around the maximum light, these spectral features are dominated by the photospheric components which are noticeably narrower than normal SNe Ia. The post-maximum velocity of the photosphere remains almost constant at ~12000km/s for about one month, reminiscent of the behavior of some luminous SNe Ia like SN 1991T. We propose that SN 2012fr may represent a subset of the SN 1991T-like SNe Ia viewed in a direction with a clumpy or shell-like structure of ejecta, in terms of a significant level of polarization reported in Maund et al. (2013MNRAS.433L..20M).
- ID:
- ivo://CDS.VizieR/J/AJ/151/125
- Title:
- Optical and UV photometry of SN 2013dy
- Short Name:
- J/AJ/151/125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extensive and independent observations of Type Ia supernova (SNIa) SN2013dy are presented, including a larger set of UBVRI photometry and optical spectra from a few days before the peak brightness to ~200days after explosion, and ultraviolet (UV) photometry spanning from t~-10days to t~+15days refers to the B band maximum. The peak brightness (i.e., M_B_=-19.65+/-0.40mag; L_max_=[1.95+/-0.55]*10^43^/ergs) and the mass of synthesized ^56^Ni (i.e., M(^56^Ni)=0.90+/-0.26M_{Sun}_) are calculated, and they conform to the expectation for an SNIa with a slow decline rate (i.e., {Delta}m_15_(B)=0.90+/-0.03mag). However, the near infrared (NIR) brightness of this SN (i.e., M_H_=-17.33+/-0.30mag) is at least 1.0mag fainter than usual. Besides, spectroscopy classification reveals that SN2013dy resides on the border of "core normal" and "shallow silicon" subclasses in the Branch et al. classification scheme, or on the border of the "normal velocity" SNeIa and 91T/99aa-like events in the Wang et al. system. These suggest that SN2013dy is a slow-declining SNIa located on the transitional region of nominal spectroscopic subclasses and might not be a typical normal sample of SNeIa.
- ID:
- ivo://CDS.VizieR/J/ApJS/190/166
- Title:
- Optical catalog of AKARI NEP-wide survey
- Short Name:
- J/ApJS/190/166
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the source catalog and the properties of the B-, R-, and I-band images obtained to support the AKARI North Ecliptic Pole Wide (NEP-Wide) survey. The NEP-Wide is an AKARI infrared imaging survey of the north ecliptic pole covering a 5.8deg^2^ area over 2.5-6um wavelengths. The optical imaging data were obtained at the Maidanak Observatory in Uzbekistan using the Seoul National University 4kx4k Camera on the 1.5m telescope. These images cover 4.9deg^2^ where no deep optical imaging data are available. Our B-, R-, and I-band data reach the depths of ~23.4, ~23.1, and ~22.3mag(AB) at 5{sigma}, respectively. The source catalog contains 96460 objects in the R band, and the astrometric accuracy is about 0.15" at 1{sigma} in each RA and DEC direction. These photometric data will be useful for many studies including identification of optical counterparts of the infrared sources detected by AKARI, analysis of their spectral energy distributions from optical through infrared, and the selection of interesting objects to understand the obscured galaxy evolution.
