- ID:
- ivo://CDS.VizieR/J/AJ/154/129
- Title:
- PSYM-WIDE: planetary-mass companions to YMG members
- Short Name:
- J/AJ/154/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a direct imaging survey for very large separation (>100 AU), low-mass companions around 95 nearby young K5-L5 stars and brown dwarfs. They are high-likelihood candidates or confirmed members of the young (~<150 Myr) {beta} Pictoris and AB Doradus moving groups (ABDMG) and the TW Hya, Tucana-Horologium, Columba, Carina, and Argus associations. Images in i' and z' filters were obtained with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South to search for companions down to an apparent magnitude of z'~22-24 at separations >~20" from the targets and in the remainder of the wide 5.5'x5.5' GMOS field of view. This allowed us to probe the most distant region where planetary-mass companions could be gravitationally bound to the targets. This region was left largely unstudied by past high-contrast imaging surveys, which probed much closer-in separations. This survey led to the discovery of a planetary-mass (9-13 M_Jup_) companion at 2000 AU from the M3V star GU Psc, a highly probable member of ABDMG. No other substellar companions were identified. These results allowed us to constrain the frequency of distant planetary-mass companions (5-13 M_Jup_) to 0.84_-0.66_^+6.73^% (95% confidence) at semimajor axes between 500 and 5000 AU around young K5-L5 stars and brown dwarfs. This is consistent with other studies suggesting that gravitationally bound planetary-mass companions at wide separations from low-mass stars are relatively rare.
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- ID:
- ivo://CDS.VizieR/J/ApJS/227/11
- Title:
- PS1 z>5.6 quasars follow-up
- Short Name:
- J/ApJS/227/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Luminous quasars at z>5.6 can be studied in detail with the current generation of telescopes and provide us with unique information on the first gigayear of the universe. Thus far, these studies have been statistically limited by the number of quasars known at these redshifts. Such quasars are rare, and therefore, wide-field surveys are required to identify them, and multiwavelength data are required to separate them efficiently from their main contaminants, the far more numerous cool dwarfs. In this paper, we update and extend the selection for the z~6 quasars presented in Banados+ (2014AJ....148...14B) using the Pan-STARRS1 (PS1) survey. We present the PS1 distant quasar sample, which currently consists of 124 quasars in the redshift range 5.6<~z<~6.7 that satisfy our selection criteria. Of these quasars, 77 have been discovered with PS1, and 63 of them are newly identified in this paper. We present the composite spectra of the PS1 distant quasar sample. This sample spans a factor of ~20 in luminosity and shows a variety of emission line properties. The number of quasars at z>5.6 presented in this work almost doubles the previously known quasars at these redshifts, marking a transition phase from studies of individual sources to statistical studies of the high-redshift quasar population, which was impossible with earlier, smaller samples.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/58
- Title:
- PTF 12dam & iPTF 13dcc follow-up
- Short Name:
- J/ApJ/835/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the light curves of the hydrogen-poor superluminous supernovae (SLSNe I) PTF 12dam and iPTF 13dcc, discovered by the (intermediate) Palomar Transient Factory. Both show excess emission at early times and a slowly declining light curve at late times. The early bump in PTF 12dam is very similar in duration (~10days) and brightness relative to the main peak (2-3mag fainter) compared to that observed in other SLSNe I. In contrast, the long-duration (>30days) early excess emission in iPTF 13dcc, whose brightness competes with that of the main peak, appears to be of a different nature. We construct bolometric light curves for both targets, and fit a variety of light-curve models to both the early bump and main peak in an attempt to understand the nature of these explosions. Even though the slope of the late-time decline in the light curves of both SLSNe is suggestively close to that expected from the radioactive decay of ^56^Ni and ^56^Co, the amount of nickel required to power the full light curves is too large considering the estimated ejecta mass. The magnetar model including an increasing escape fraction provides a reasonable description of the PTF 12dam observations. However, neither the basic nor the double-peaked magnetar model is capable of reproducing the light curve of iPTF 13dcc. A model combining a shock breakout in an extended envelope with late-time magnetar energy injection provides a reasonable fit to the iPTF 13dcc observations. Finally, we find that the light curves of both PTF 12dam and iPTF 13dcc can be adequately fit with the model involving interaction with the circumstellar medium.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A106
- Title:
- PTF11mnb Bgri light curves
- Short Name:
- J/A+A/609/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study PTF11mnb, a He-poor supernova (SN) whose light curves resemble those of SN 2005bf, a peculiar double-peaked stripped-envelope (SE) SN, until the declining phase after the main peak. We investigate the mechanism powering its light curve and the nature of its progenitor star. Optical photometry and spectroscopy of PTF11mnb are presented. We compared light curves, colors and spectral properties to those of SN 2005bf and normal SE SNe. We built a bolometric light curve and modeled this light curve with the SuperNova Explosion Code (SNEC) hydrodynamical code explosion of a MESA progenitor star and semi-analytic models.
- ID:
- ivo://CDS.VizieR/J/ApJ/824/6
- Title:
- PTF obs. of a precursor to SNHunt 275 2015 May event
- Short Name:
- J/ApJ/824/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The progenitors of some supernovae (SNe) exhibit outbursts with super-Eddington luminosities prior to their final explosions. This behavior is common among SNe IIn, but the driving mechanisms of these precursors are not yet well-understood. SNHunt 275 was announced as a possible new SN during 2015 May. Here we report on pre-explosion observations of the location of this event by the Palomar Transient Factory (PTF) and report the detection of a precursor about 500 days prior to the 2015 May activity (PTF 13efv). The observed velocities in the 2015 transient and its 2013 precursor absorption spectra are low (1000-2000km/s), so it is not clear yet if the recent activity indeed marks the final disruption of the progenitor. Regardless of the nature of this event, we use the PTF photometric and spectral observations, as well as Swift-UVOT observations, to constrain the efficiency of the radiated energy relative to the total kinetic energy of the precursor. We find that, using an order-of-magnitude estimate and under the assumption of spherical symmetry, the ratio of the radiated energy to the kinetic energy is in the range of 4x10^-2^ to 3.4x10^3^.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A68
- Title:
- PTF12os and iPTF13bvn spectra and light curves
- Short Name:
- J/A+A/593/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate two stripped-envelope supernovae (SNe) discovered in the nearby galaxy NGC 5806 by the (i)PTF. We classify PTF12os as a Type IIb SN based on our spectral sequence; iPTF13bvn has previously been classified as Type Ib. Our main objective is to constrain the explosion parameters of iPTF12os and iPTF13bvn, and to put constraints on the SN progenitors, using our comprehensive photometric and spectroscopic datasets.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/81
- Title:
- PTF stellar rotation periods for Pleiades members
- Short Name:
- J/ApJ/822/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stellar rotation periods (P_rot_) measured in open clusters have proved to be extremely useful for studying stars' angular momentum content and rotationally driven magnetic activity, which are both age- and mass-dependent processes. While P_rot_ measurements have been obtained for hundreds of solar-mass members of the Pleiades, measurements exist for only a few low-mass (<0.5 M_{sun}_) members of this key laboratory for stellar evolution theory. To fill this gap, we report P_rot_ for 132 low-mass Pleiades members (including nearly 100 with M=<0.45 M_{sun}_), measured from photometric monitoring of the cluster conducted by the Palomar Transient Factory in late 2011 and early 2012. These periods extend the portrait of stellar rotation at 125 Myr to the lowest-mass stars and re-establish the Pleiades as a key benchmark for models of the transport and evolution of stellar angular momentum. Combining our new P_rot_ with precise BVIJHK photometry reported by Stauffer et al. (2007, J/ApJS/172/663) and Kamai et al. (2014, J/AJ/148/30), we investigate known anomalies in the photometric properties of K and M Pleiades members. We confirm the correlation detected by Kamai et al. between a star's P_rot_ and position relative to the main sequence in the cluster's color-magnitude diagram. We find that rapid rotators have redder (V-K) colors than slower rotators at the same V, indicating that rapid and slow rotators have different binary frequencies and/or photospheric properties. We find no difference in the photometric amplitudes of rapid and slow rotators, indicating that asymmetries in the longitudinal distribution of starspots do not scale grossly with rotation rate.
- ID:
- ivo://CDS.VizieR/I/290
- Title:
- Pulkovo catalogue of 58483 stars (Pul-3)
- Short Name:
- I/290
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalogue of positions and proper motions of 58483 stars (Pul-3) has been constructed at the Pulkovo observatory. The Pul-3 is based on the results of measurements of the photographic plates ((x,y)-data) with galaxies (Deutsch's plan). The observations were made with Pulkovo Normal Astrograph (F=3467mm, D=330mm) during the periods from 1935 till 1960 (the first epoch) and from 1969 till 1986 (the second epoch). The radius of working field was 50 arcmin for all plates. The exposure times were 1 hour. All plates were taken near the meridian. The measurements of the plates were made at the Pulkovo observatory in 1970-s and in 1980-s with ASCORECORD measuring machine. Photographic magnitudes of these stars have been determined at the Pulkovo observatory. The Pulkovo plates contain stars mainly 12-16.5 magnitudes in 146 field in declination zone from -5 to +85 degrees. The maximal density of stars in the Pulkovo plates is 500 stars per square degree. The Tycho-2 catalogue (Cat. <I/259>) has been used as a reference catalogue for astrometric reductions of the photographic plates. The great stars density of the Tycho-2 provides 40-65 reference stars in working field of the Pulkovo plates. Only approximate equatorial coordinates of the optical centers of all plates had been known in initial stage of construction of the Pul-3 catalogue and thus recalculation of ones has been done. A six-parameter plate model has been used for the astrometric reduction of the plates. The residuals of the tangential coordinates of reference stars have been analysed to investigate residual systematic errors. The coma parameters have been determined and coma-dependent systematic errors have been excluded. The magnitude-dependent systematic errors and color-dependent ones were investigated. The most significant corrections for magnitude equation have been obtained for stars brighter than 9 magnitude and fainter than 14 magnitude. The most significant color corrections have been obtained in equatorial zone for declinations of stars. The corrected coordinates of all stars have been determined. On the whole, recalculation of the plates optical centers and taking into account of all revealed systematic errors provide improvement of the accuracy of coordinates of stars on 64mas and 51mas for right ascension and declination correspondingly. The new proper motions have been determined for all stars. The mean position has been calculated at the mean epoch of observations of each star using it proper motion. The mean epoch of the Pul-3 is 1963.25. The internal positional accuracy of the Pul-3 catalogue at the mean epoch of observations is 80mas. The internal accuracy of the proper motions is 5mas/yr. Comparisons of the Pul-3 with Tycho-2 and ARIHIP have been done. The Pul-3 external positional accuracy relative to Tycho-2 is 150mas at the mean epoch of the Pulovo plates. The Pul-3 catalogue successfully represents the Tycho-2 system for more than 50000 stars which are fainter than 12 magnitude in 146 fields. The stars from the Pul-3 catalogue may be used as reference stars for reductions of the positional CCD-observations of the extragalactic radio sources and small bodies of the Solar system. The 40-years difference between Pul-3 observational epoch and modern epoch will allow to determine high precision proper motions of the faint stars of the Pul-3 catalogue (about 2mas/yr-3mas/yr). Proper motions of stars from Pul-3 catalogue may be used for stellar kinematics investigations. There are two data files for user's convenience: - the file pul3.dat represents the Pul-3 catalogue; - the file centers.dat contains the equatorial coordinates of centers of the Pulkovo fields (RA, DE).
- ID:
- ivo://CDS.VizieR/I/321
- Title:
- Pulkovo SMP Photographic Catalogue
- Short Name:
- I/321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of new reduction of 1545 photographic observations of 14 selected asteroids' obtained with Normal Astrograph of Pulkovo observatory from 1948 to 1990 years presented. Photographic plates, stored in observatory's archive, was digitized using consumer flatbed scanner with special designed technique. The accuracy of measured photoplates was performed. The UCAC3 was used as reference catalog. The analysis of instrumental systematic effects, revealing in common distortion and magnitude equation, was performed and taken into account. The equatorial coordinates of 1378 single observations of selected asteroids was obtained and was made their comparison with results of reduction of this material obtained earlier. 1475 positions of stars with large proper motions from LSPM catalog was measured among background objects.
- ID:
- ivo://CDS.VizieR/J/ApJS/232/23
- Title:
- 27 pulsating DA WDs follow-up observations
- Short Name:
- J/ApJS/232/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometry and spectroscopy for 27 pulsating hydrogen-atmosphere white dwarfs (DAVs; a.k.a. ZZ Ceti stars) observed by the Kepler space telescope up to K2 Campaign 8, an extensive compilation of observations with unprecedented duration (>75 days) and duty cycle (>90%). The space-based photometry reveals pulsation properties previously inaccessible to ground- based observations. We observe a sharp dichotomy in oscillation mode line widths at roughly 800s, such that white dwarf pulsations with periods exceeding 800s have substantially broader mode line widths, more reminiscent of a damped harmonic oscillator than a heat-driven pulsator. Extended Kepler coverage also permits extensive mode identification: we identify the spherical degree of 87 out of 201 unique radial orders, providing direct constraints of the rotation period for 20 of these 27 DAVs, more than doubling the number of white dwarfs with rotation periods determined via asteroseismology. We also obtain spectroscopy from 4m-class telescopes for all DAVs with Kepler photometry. Using these homogeneously analyzed spectra, we estimate the overall mass of all 27 DAVs, which allows us to measure white dwarf rotation as a function of mass, constraining the endpoints of angular momentum in low- and intermediate-mass stars. We find that 0.51-0.73M{sun} white dwarfs, which evolved from 1.7-3.0M{sun} ZAMS progenitors, have a mean rotation period of 35hr with a standard deviation of 28hr, with notable exceptions for higher-mass white dwarfs.
