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- ID:
- ivo://CDS.VizieR/J/MNRAS/435/771
- Title:
- Nova Mon 2012 BV(RI)c light curves
- Short Name:
- J/MNRAS/435/771
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and discuss accurate and densely mapped BVR_C_I_C_ light curves of the neon Nova Mon 2012, supplemented by the evolution in Stromgren b and y bands and in the integrated flux of relevant emission lines. Our monitoring started with the optical discovery of the nova (50days past the first detection in gamma-rays by Fermi-LAT) and extend to day +270, well past the end of the super-soft phase in X-rays. The nova was discovered during the nebular decline, well past t_3_ and the transition to optically thin ejecta. It displayed very smoothly evolving light curves. A bifurcation between y and V light curves took place at the start of the super-soft X-ray source (SSS) phase, and a knee developed towards the end of the SSS phase. The apparent magnitude of the nova at the unobserved optical maximum is constrained to +3<=V<=4.5. The appearance, grow in amplitude and then demise of a 0.29585 (+/-0.00002) days orbital modulation of the optical brightness was followed along the nova evolution. The observed modulation, identical in phase and period with the analogue seen in the X-ray and satellite ultraviolet, has a near-sinusoidal shape and a weak secondary minimum at phase 0.5. We favour an interpretation in terms of super-imposed ellipsoidal distortion of the Roche lobe filling companion and irradiation of its side facing the WD. Similar light curves are typical of symbiotic stars where a Roche lobe filling giant is irradiated by a very hot WD. Given the high orbital inclination, mutual occultation between the donor star and the accretion disc could contribute to the observed modulation. The optical+infrared spectral energy distribution of Nova Mon 2012 during the quiescence preceding outburst is nicely fitted by an early K-type main-sequence star (~K3V) at 1.5kpc distance, reddened by E(B-V)=0.38, with a WD companion and an accretion disc contributing to the observed blue excess and moderate H{alpha} emission. A typical early K-type main-sequence star with a mass of ~0.75M_{sun}_ and a radius of ~0.8 R{sun} would fill its Roche lobe for a P=0.29585d orbital period and a more massive WD companion (as implied by the large Ne overabundance of the ejecta).
- ID:
- ivo://CDS.VizieR/J/A+A/543/A86
- Title:
- Nova V1280 Sco BVRcIcy light curves
- Short Name:
- J/A+A/543/A86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical (B, V, Rc, Ic and y) and near-infrared (J, H, and Ks) photometric and spectroscopic observations of a classical nova V1280 Scorpii for five years from 2007 to 2011. Our photometric observations show a declining event in optical bands shortly after the maximum light, which took about 250 days to recover. This event was most probably caused by dust formation. The event was accompanied by a short (~30 days) re-brightening episode (~2.5mag in V), which suggests that there had been some re-ignition of the surface nuclear burning. After 2008, the y band observations show a very long plateau at around y=10.5 for more than 1000 days until April 2011 (~1500 days after the maximum light). The nova had taken a very long time (~50 months) to enter the nebular phase, according to a clear detection of both [OIII] 4959 and 5007 and is still continuing to generate the wind caused by H-burning. This finding suggests that historically V1280 Sco is evolving at its slowest ever measured rate. The interval from the maximum light (2007 February 16) to the beginning of the nebular phase is longer than any previously known slow novae: V723 Cas (18 months), RR Pic (10 months), or HR Del (8 months). It suggests that the mass of a white dwarf in the V1280 Sco system might be 0.6M_{sun}_ or lower. The distance, based on our measurements of the expansion velocity combined with the directly measured size of the dust shell, is estimated to be 1.1+/-0.5kpc.
- ID:
- ivo://CDS.VizieR/J/A+A/544/A114
- Title:
- Optical identification of 1RXS J180431.1-273932
- Short Name:
- J/A+A/544/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The X-ray source 1RXS J180431.1-273932 has been proposed as a new member of the symbiotic X-ray binary (SyXB) class of systems, which are composed of a late-type giant that loses matter to an extremely compact object, most likely a neutron star. In this paper, we present an optical campaign of imaging plus spectroscopy on selected candidate counterparts of this object. We also reanalyzed the available archival X-ray data collected with XMM-Newton.
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/4441
- Title:
- Outburst catalogue of cataclysmic variables
- Short Name:
- J/MNRAS/456/4441
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Outburst Catalogue contains a wide variety of observational properties for 722 dwarf nova-type (DN) cataclysmic variables (CVs) and 309 CVs of other types from the Catalina Real-time Transient Survey. In particular, it includes the apparent outburst and quiescent V-band magnitudes, duty cycles, limits on the recurrence time, upper- and lower-limits on the distance and absolute quiescent magnitudes, colour information, orbital parameters, and X-ray counterparts. These properties were determined by means of a classification script presented in this paper. The DN in the catalogue show a correlation between the outburst duty cycle and the orbital period (and outburst recurrence time), as well as between the quiescent absolute magnitude and the orbital period (and duty cycle). This is the largest sample of dwarf nova properties collected to date. Besides serving as a useful reference for individual systems and a means of selecting objects for targeted studies, it will prove valuable for statistical studies that aim to shed light on the formation and evolution of cataclysmic variables.
- ID:
- ivo://CDS.VizieR/J/A+A/573/A61
- Title:
- Photometry of new eclipsing CVs
- Short Name:
- J/A+A/573/A61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of eclipses and the first orbital period measurements for four cataclysmic variables, plus the first orbital period measurements for one known eclipsing and two magnetic systems. SDSS J093537.46+161950.8 exhibits 1-mag deep eclipses with a period of 92.245 min. SDSS J105754.25+275947.5 has short and deep eclipses and an orbital period of 90.44 min. Its light curve has no trace of a bright spot and its spectrum is dominated by the white dwarf component, suggesting a low mass accretion rate and a very low-mass and cool secondary star. CSS J132536+210037 shows 1-mag deep eclipses each separated by 89.821 min. SDSS J075653.11+085831.8 shows 2-mag deep eclipses on a period of 197.154 min. CSS J112634-100210 is an eclipsing dwarf nova identified in the Catalina Real Time Transit Survey, for which we measure a period of 111.523 min. SDSS J092122.84+203857.1 is a magnetic system with an orbital period of 84.240 min; its light curve is a textbook example of cyclotron beaming. A period of 158.72 min is found for the faint magnetic system SDSS J132411.57+032050.4, whose orbital light variations are reminiscent of AM Her. Improved orbital period measurements are also given for three known SDSS cataclysmic variables. We investigate the orbital period distribution and fraction of eclipsing systems within the SDSS sample and for all cataclysmic variables with a known orbital period, with the finding that the fraction of known CVs which are eclipsing is not strongly dependent on the orbital period.
- ID:
- ivo://CDS.VizieR/J/ApJ/721/412
- Title:
- Photometry of polar CV* 1RXS J173006.4+033813
- Short Name:
- J/ApJ/721/412
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 1RXS J173006.4+033813, a polar cataclysmic variable with a period of 120.21 minutes. The white dwarf primary has a magnetic field of B=42^+6^_-5_MG and the secondary is an M3 dwarf. The system shows highly symmetric double-peaked photometric modulation in the active state as well as in quiescence. These arise from a combination of cyclotron beaming and ellipsoidal modulation. The projected orbital velocity of the secondary is K_2_=390+/-4km/s. We place an upper limit of 830+/-65pc on the distance.
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/584/A12
- Title:
- PNV J03093063+2638031 outburst evolution
- Short Name:
- J/A+A/584/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have monitored the 2014 superoutburst of the WZ Sge-type transient PNV J03093063+2638031 for more than four months, from V=11.0 maximum brightness down to V=18.4mag, close to quiescence value, by obtaining BV Rc Ic photometry and low resolution fluxed spectroscopy. The evolution was normal and no late-time 'echo' outbursts were observed. The absolute integrated flux of emission lines kept declining along the superoutburst, and their increasing contrast with the underlying continuum was simply the result of the faster decline of the continuum compared to the emission lines. Inspection of historical Harvard plates covering the 1899-1981 period did not reveal previous outbursts, neither 'normal' nor 'super'. We discovered an extended emission nebula (radius ~1-arcmin) around PNV J03093063+2638031, that became visible for a few months as the result of photo-ionization from the superoutburst of the central star. The nebula is not present on Palomar I and II sky survey images and it quickly disappeared when the outburst was over. From the rate at which the ionization front swept through the nebula, we derive a distance of ~120pc to the system. The nebula is density bounded with an outer radius of 0.03pc, and the absolute magnitude of the central star in quiescence is M_V_~14.2mag. The electron density in the nebula is estimated to be 10^5^cm^-3^ from the observed recombination time scale. Given the considerable substructures seen across the nebula, a low filling factor is inferred. Similar nebulae have not been reported for other WZ Sge objects and the challenges posed to models are considered.
- ID:
- ivo://CDS.VizieR/J/AJ/150/170
- Title:
- Radial velocities of 7 cataclysmic binaries
- Short Name:
- J/AJ/150/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From a set of 13 cataclysmic binaries that were discovered in the Swift Burst Alert Telescope (BAT) survey, we conducted time-resolved optical spectroscopy and/or time-series photometry of 11, with the goal of measuring their orbital periods and searching for spin periods. Seven of the objects in this study are new optical identifications. Orbital periods are found for seven targets, ranging from 81 minutes to 20.4hr. PBC J0706.7+0327 is an AM Herculis star (polar) based on its emission-line variations and large amplitude photometric modulation on the same period. Swift J2341.0+7645 may be a polar, although the evidence here is less secure. Coherent pulsations are detected from two objects, Swift J0503.7-2819 (975s) and Swift J0614.0+1709 (1412s and 1530s, spin and beat periods, respectively), indicating that they are probable intermediate polars (DQ Herculis stars). For two other stars, longer spin periods are tentatively suggested. We also present the discovery of a 2.00hr X-ray modulation from RX J2015.6+3711, possibly a contributor to Swift J2015.9+3715, and likely a polar.
