- ID:
- ivo://CDS.VizieR/J/A+A/363/1081
- Title:
- Non-linear limb-darkening law for LTE models
- Short Name:
- J/A+A/363/1081
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new non-linear limb-darkening law, based on the Least-Squares Method (LSM), is presented. This law is able to describe the intensity distribution much more accurately than any of the old ones given that the differences I(model)-I(fitting) are of some order of magnitude smaller than those derived from other approximations. This new law shows several advantages: it represents well the intensity distribution, the flux is conserved with high accuracy and it permits the use of a single law for the whole HR Diagram since that the bi-parametric laws are only marginally valid in certain range of effective temperatures. The limb-darkening coefficients are computed for the 12 commonly used photometric bands u v b y U B V R I J H K. Bolometric and monochromatic calculations are also available. The computations are presented for 19 metallicities ranging from 10^-5^ up to 10^+1^ solar abundances, with log(g) varying between 0 and 5.0 and effective temperatures between 2000K-50000K. Results for microturbulent velocities of 0, 1, 2, 4, 8 km/s are also available. With this set of data it was possible to investigate, for the first time, the influence of such parameters in the limb-darkening. Limb-brightening, instead of limb-darkening, was detected for some models. It is shown that the limb-darkening coefficients derived using the Flux Conservation Method (FCM) do not describe very well the intensity distribution, mainly near the border of the disk. On the contrary, the present coefficients, based on the LSM, represent very well the function I({mu}) at any part of the disk for any filter or wavelength, log(g), effective temperature, metallicity and microturbulent velocity. The results are presented here as synthetic tables containing the limb-darkening coefficients. The 46 tables announced in the paper are also accessible as the "original.tar" file.
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- ID:
- ivo://CDS.VizieR/J/A+A/401/657
- Title:
- Non-linear limb-darkening law for LTE models. II.
- Short Name:
- J/A+A/401/657
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As an extension of our previous investigations on stellar atmospheres (Claret, 2000, Cat. <J/A+A/363/1081>), the limb-darkening coefficients for the Geneva and Walraven photometric systems are presented for the first time using the ATLAS and PHOENIX models. They cover a wide range of values of logg, T_eff_, metallicities and microturbulent velocities. In addition to the traditional applications of limb-darkening coefficients, the present ones are now being used in the interpretation of phase shift of B and A-F type pulsating stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/440/3402
- Title:
- Nova Cep 2013 (V809 Cep) UBVRI light curves
- Short Name:
- J/MNRAS/440/3402
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BVR_C_I_C_ photometry and low-, medium- and high-resolution echelle fluxed spectroscopy is presented and discussed for three faint, heavily reddened novae of the Feii-type which erupted in 2013. V1830 Nova Aql 2013 reached a peak V=15.2mag on 2013 Oct 30.3 UT and suffered from a huge E(B-V)~2.6mag reddening. After a rapid decline, when the nova was {Delta}V=1.7mag below maximum, it entered a flat plateau where it remained for a month until solar conjunction prevented further observations. Similar values were observed for V556 Nova Ser 2013, that peaked near R_C_~12.3 around 2013 Nov 25 and soon went lost in the glare of sunset sky. A lot more observations were obtained for V809 Nova Cep 2013, that peaked at V=11.18 on 2013 Feb 3.6. The reddening is E(B-V)~1.7 and the nova is located within or immediately behind the spiral Outer Arm, at a distance of ~6.5kpc as constrained by the velocity of interstellar atomic lines and the rate of decline from maximum. While passing at t_3_, the nova begun to form a thick dust layer that caused a peak extinction of {Delta}V>5mag, and took 125d to completely dissolve. The dust extinction turned from neutral to selective around 6000{AA}. Monitoring the time evolution of the integrated flux of emission lines allowed us to constrain the region of dust formation in the ejecta to be above the region of formation of OI 7774{AA} and below that of CaII triplet. Along the decline from maximum and before the dust obscuration, the emission line profiles of Nova Cep 2013 developed a narrow component (FWHM=210km/s) superimposed on to the much larger normal profile, making it a member of the so-far exclusive but growing club of novae displaying this peculiar feature. Constrains based on the optical thickness of the innermost part of the ejecta and on the radiated flux, place the origin of the narrow feature within highly structured internal ejecta and well away from the central binary.
- 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/other/CoSka/39.43
- Title:
- Nova Tri UBV(RI)c light curves
- Short Name:
- J/other/CoSka/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the UBV(RI)c photometry of the dwarf nova Tri 2008 = OT J023839.1+355648 obtained during its superoutburst started on October 25, 2008. The object can be classified as a WZ Sge-type dwarf nova. The period of early superhumps 0.05307 days was detected in the first 7 days of the superoutburst. The period of ordinary superhumps 0.053663 days, detected in days 8-23 of the superoutburst, is the shortest one among WZ Sge-type objects. After one month, the dwarf nova returned to its pre-outburst state. A sudden increase of activity of the object during its quiescent stage was detected on January 11, 2009.
- ID:
- ivo://CDS.VizieR/J/PASP/123/1149
- Title:
- NSV 11154 BVRI light curves
- Short Name:
- J/PASP/123/1149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NSV 11154 has been confirmed as a new member of the rare hydrogen- deficient R Coronae Borealis (RCB) stars based on new photometric and spectroscopic data. Using new photometry, as well as archival plates from the Harvard archive, we have constructed the historical lightcurve of NSV 11154 from 1896 to the present. The lightcurve shows the sudden, deep, irregularly spaced declines characteristic of RCB stars.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2206
- Title:
- NTT, HDF-S and HDF-N photometric redshifts
- Short Name:
- J/AJ/120/2206
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and compare in this paper new photometric redshift catalogs of the galaxies in three public fields: the NTT Deep Field, the HDF-N, and the HDF-S. In the case of the NTT Deep Field, we present here a new photometric catalog, obtained by combining the existing BVrI and JKs with new deep U observations acquired with NTT-SUSI2, and which includes also the contiguous field centered on the z_em_=4.7 quasar BR 1202-0
- ID:
- ivo://CDS.VizieR/J/PAZh/27/942
- Title:
- Nuclear activity of NGC 5548
- Short Name:
- J/PAZh/27/942
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UBVRI observations of the nucleus of the Seyfert galaxy NGC 5548 from 1990 until 2000 at four astronomical observatories are given in Table2. All data have been reduced to a single system and are given for an A=14.3" aperture.
- ID:
- ivo://CDS.VizieR/J/PAZh/27/83
- Title:
- Nuclear activity of NGC 4151 in 1989-2000
- Short Name:
- J/PAZh/27/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Broadband UBVRI observations of the nucleus of the Seyfert galaxy NGC 4151 from 1989 until 2000 at three astronomical observatories: the Crimean Station of the Sternberg astronomical institute, The Special Astronomical observatory in the Caucasus and the Maidanac observatory of the Ulugbek Astronomical institute in Uzbekistan. All data have been reduced to a single system and are given for an A=27.5" aperture.
- ID:
- ivo://CDS.VizieR/J/ApJ/873/L3
- Title:
- NUV to NIR photometry of type IIP ASASSN-16at
- Short Name:
- J/ApJ/873/L3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report distinctly double-peaked H{alpha} and H{beta} emission lines in the late-time, nebular-phase spectra (>~200 days) of the otherwise normal at early phases (<~100 days) type IIP supernova ASASSN-16at (SN2016X). Such distinctly double-peaked nebular Balmer lines have never been observed for a type II SN. The nebular-phase Balmer emission is driven by the radioactive ^56^Co decay, so the observed line profile bifurcation suggests a strong bipolarity in the ^56^Ni distribution or in the line-forming region of the inner ejecta. The strongly bifurcated blueshifted and redshifted peaks are separated by ~3x10^3^km/s and are roughly symmetrically positioned with respect to the host-galaxy rest frame, implying that the inner ejecta are composed of two almost-detached blobs. The red peak progressively weakens relative to the blue peak, and disappears in the 740 days spectrum. One possible reason for the line-ratio evolution is increasing differential extinction from continuous formation of dust within the envelope, which is also supported by the near-infrared flux excess that develops after ~100 days.
