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1991. Photometric Variability of HD 51585
ID:
ivo://CDS.VizieR/J/PAZh/32/662
Title:
Photometric Variability of HD 51585
Short Name:
J/PAZh/32/662
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photoelectric observations of HD 51585 (OY Gem), a B[e] star with an infrared excess and a candidate for protoplanetary nebulae, obtained with a 60-cm telescope at the Crimean Station of the Sternberg Astronomical Institute in 1992-2005 are presented. The star exhibited rapid irregular brightness variations with amplitudes from 0.1mag in the V band to 0.2mag in the U band within the observing season as well as slow systematic variations with amplitudes from 0.3mag in the V band to 0.65mag in the U band and with a quasi-period of ~2800days. The B-V color index varied within 0.1mag and did not follow the slow systematic brightness variations, while U-B correlated with the U brightness and varied between 0.7mag at maximum light and 0.35mag at minimum light. Our low-resolution spectroscopy performed in 1994-2005 has revealed significant variability of the Balmer and Paschen hydrogen emission lines as well as the He I and OI lines. Equivalent widths are given for the HI, He I, OI, and Fe II lines; a correlation has been found between the star's photometric variability and the hydrogen line intensities. Our joint analysis of the photometric and spectroscopic data suggests that variations in a strong stellar wind are responsible for the variability of the star.
1992. Photometry and lines of (z~0.2-1.0) galaxies
ID:
ivo://CDS.VizieR/J/A+A/448/893
Title:
Photometry and lines of (z~0.2-1.0) galaxies
Short Name:
J/A+A/448/893
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the spectrophotometric properties of a sample of 141 emission-line galaxies at redshifts in the range 0.2<z<1.0 with a peak around 0.2<=z<=0.4. The analysis is based on medium resolution (Rs=500-600), optical spectra obtained at VLT and Keck. The targets are mostly "Canada-France Redshift Survey" (<VII/225>) emission-line galaxies, with the addition of field galaxies randomly selected behind lensing clusters. We complement this sample with galaxy spectra from the "Gemini Deep Deep Survey" (<J/AJ/127/2455>) public data release. We have computed absolute magnitudes of the galaxies and measured the line fluxes and equivalent widths of the main emission/absorption lines. The last two have been measured after careful subtraction of the fitted stellar continuum using the platefit software originally developed for the SDSS and adapted to our data. We present a careful comparison of this software with the results of manual measurements.
1993. Photometry and Metallicity in ABCG 209 galaxies
ID:
ivo://CDS.VizieR/J/A+A/424/79
Title:
Photometry and Metallicity in ABCG 209 galaxies
Short Name:
J/A+A/424/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse the properties of galaxy populations in the rich Abell cluster ABCG 209 at redshift z~0.21, on the basis of spectral classification of 102 member galaxies. We take advantage of available structural parameters to study separately the properties of bulge-dominated and disk-dominated galaxies. The star formation histories of the cluster galaxy populations are investigated by using line strengths and the 4000{AA} break, through a comparison to stellar population synthesis models. The dynamical properties of different spectral classes are examined in order to infer the past merging history of ABCG 209. The cluster is characterized by the presence of two components: an old galaxy population, formed very early (z_f>~3.5), and a younger (z_f>~1.2) population of infalling galaxies. We find evidence of a merger with an infalling group of galaxies occurred 3.5-4.5Gyr ago. The correlation between the position of the young H_delta-strong galaxies and the X-ray flux shows that the hot intracluster medium triggered a starburst in this galaxy population ~3Gyr ago.
1994. Photometry and spectra of SN 2017dio
ID:
ivo://CDS.VizieR/J/ApJ/854/L14
Title:
Photometry and spectra of SN 2017dio
Short Name:
J/ApJ/854/L14
Date:
21 Oct 2021
Publisher:
CDS
Description:
SN 2017dio shows both spectral characteristics of a type-Ic supernova (SN) and signs of a hydrogen-rich circumstellar medium (CSM). Prominent, narrow emission lines of H and He are superposed on the continuum. Subsequent evolution revealed that the SN ejecta are interacting with the CSM. The initial SN Ic identification was confirmed by removing the CSM interaction component from the spectrum and comparing with known SNe Ic, and reversely, adding a CSM interaction component to the spectra of known SNe Ic and comparing them to SN 2017dio. Excellent agreement was obtained with both procedures, reinforcing the SN Ic classification. The light curve constrains the pre-interaction SN Ic peak absolute magnitude to be around Mg=-17.6mag. No evidence of significant extinction is found, ruling out a brighter luminosity required by a SN Ia classification. These pieces of evidence support the view that SN 2017dio is a SN Ic, and therefore the first firm case of a SN Ic with signatures of hydrogen-rich CSM in the early spectrum. The CSM is unlikely to have been shaped by steady-state stellar winds. The mass loss of the progenitor star must have been intense, dM/dt~0.02({epsilon}_Ha_/0.01)^-1^*(v_wind_/500km/s)* (v_shock_/10000km/s)^-3^M_{sun}_/yr, peaking at a few decades before the SN. Such a high mass loss rate might have been experienced by the progenitor through eruptions or binary stripping.
1995. Photometry and spectroscopy in IC 2391
ID:
ivo://CDS.VizieR/J/ApJ/706/1484
Title:
Photometry and spectroscopy in IC 2391
Short Name:
J/ApJ/706/1484
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the stellar and substellar mass function (MF) of the open cluster IC 2391, plus its radial dependence, and use this to put constraints on the formation mechanism of brown dwarfs (BDs). Our multi-band optical and infrared photometric survey with spectroscopic follow-up covers 11deg^2^, making it the largest survey of this cluster to date. From our preliminary spectroscopic follow-up, to confirm BD status and cluster membership, we find that all candidates are M dwarfs (in either the field or the cluster), demonstrating the efficiency of our photometric selection method in avoiding contaminants (e.g., red giants). About half of our photometric candidates for which we have spectra are spectroscopically confirmed as cluster members; two are new spectroscopically confirmed BD members of IC 2391.
1996. Photometry and spectroscopy of BHB candidates
ID:
ivo://CDS.VizieR/J/AJ/135/564
Title:
Photometry and spectroscopy of BHB candidates
Short Name:
J/AJ/135/564
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a complete spectroscopic survey of 2414 2MASS-selected blue horizontal branch (BHB) candidates selected over 4300{deg}^2^ of the sky. We identify 655 BHB stars in this non-kinematically selected sample. We calculate the luminosity function of field BHB stars, and find evidence for very few hot BHB stars in the field.
1997. Photometry and spectroscopy of HAT-P-49
ID:
ivo://CDS.VizieR/J/AJ/147/84
Title:
Photometry and spectroscopy of HAT-P-49
Short Name:
J/AJ/147/84
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of the transiting extrasolar planet HAT-P-49b. The planet transits the bright (V=10.3) slightly evolved F-star HD340099 with a mass of 1.54M_{Sun}_ and a radius of 1.83R_{Sun}_. HAT-P-49b is orbiting one of the 25 brightest stars to host a transiting planet which makes this a favorable candidate for detailed follow-up. This system is an especially strong target for Rossiter-McLaughlin follow-up due to the host star's fast rotation, 16km/s. The planetary companion has a period of 2.6915 days, mass of 1.73M_J_, and radius of 1.41R_J_. The planetary characteristics are consistent with that of a classical hot Jupiter but we note that this is the fourth most massive star to host a transiting planet with both M_p_ and R_p_ well determined.
1998. Photometry and spectroscopy of LS V+44 17
ID:
ivo://CDS.VizieR/J/AJ/151/104
Title:
Photometry and spectroscopy of LS V+44 17
Short Name:
J/AJ/151/104
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the spectroscopic and photometric observations on the Be/X-ray binary RX J0440.9+4431 from 2001 to 2014. The short-term and long-term variability of the H{alpha} line profile indicates that one-armed global oscillations existed in the circumstellar disk. Several positive and negative correlations between the V-band brightness and the H{alpha} intensity were found from the long-term photometric and spectroscopic observations. We suggest that the monotonic increase of the V-band brightness and the H{alpha} brightness between our 2005 and 2007 observations might be the result of a continuous mass ejection from the central Be star, while the negative correlation in 2007-2010 should be caused by the cessation of mass loss from the Be star just before the decline in V-band brightness began (around our 2007 observations). With the extension of the ejection material, the largest circumstellar disk during the last two decades has been observed in our 2010 observations with an equivalent width of approximately -12.88{AA}, which corresponds to a circumstellar disk with a size of 12.9 times the radius of the central Be star. Three consecutive X-ray outbursts peaking around MJD 55293, 55444, and 55591 might be connected with the largest circumstellar disk around the Be star. We also use the orbital motion of the neutron star as a probe to constrain the structure of the circumstellar disk and estimate the eccentricity of the binary system to be >=0.4. After three years of the H{alpha} intensity decline after the X-ray outbursts, a new circumstellar disk was being formed around the Be star after our 2013 observations.
1999. Photometry and spectroscopy of Markarian 266
ID:
ivo://CDS.VizieR/J/AJ/144/125
Title:
Photometry and spectroscopy of Markarian 266
Short Name:
J/AJ/144/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results of observations with the Spitzer, Hubble, GALEX, Chandra, and XMM-Newton space telescopes are presented for the luminous infrared galaxy (LIRG) merger Markarian 266. The SW (Seyfert 2) and NE (LINER) nuclei reside in galaxies with Hubble types SBb (pec) and S0/a (pec), respectively. Both companions are more luminous than L* galaxies and they are inferred to each contain a {approx}2.5x10^8^M_{sun}_ black hole. Although the nuclei have an observed hard X-ray flux ratio of f_X_(NE)/f_X_(SW)=6.4, Mrk 266 SW is likely the primary source of a bright Fe K{alpha} line detected from the system, consistent with the reflection-dominated X-ray spectrum of a heavily obscured active galactic nucleus (AGN). Optical knots embedded in an arc with aligned radio continuum radiation, combined with luminous H_2_line emission, provide evidence for a radiative bow shock in an AGN-driven outflow surrounding the NE nucleus. A soft X-ray emission feature modeled as shock-heated plasma with T~10^7^K is cospatial with radio continuum emission between the galaxies. Mid-infrared diagnostics provide mixed results, but overall suggest a composite system with roughly equal contributions of AGN and starburst radiation powering the bolometric luminosity. Approximately 120 star clusters have been detected, with most having estimated ages less than 50Myr. Detection of 24{mu}m emission aligned with soft X-rays, radio continuum, and ionized gas emission extending ~34" (20kpc) north of the galaxies is interpreted as ~2x10^7^M_{sun}_ of dust entrained in an outflowing superwind. At optical wavelengths this Northern Loop region is resolved into a fragmented morphology indicative of Rayleigh-Taylor instabilities in an expanding shell of ionized gas. Mrk 266 demonstrates that the dust "blow-out" phase can begin in a LIRG well before the galaxies fully coalesce during a subsequent ultraluminous infrared galaxy (ULIRG) phase, and rapid gas consumption in luminous dual AGNs with kiloparsec-scale separations early in the merger process may explain the paucity of detected binary QSOs (with parsec-scale orbital separations) in spectroscopic surveys. An evolutionary sequence is proposed representing a progression from dual to binary AGNs, accompanied by an increase in observed L_x_/L_ir_ ratios by over two orders of magnitude.
2000. Photometry and spectroscopy of NGC 6520
ID:
ivo://CDS.VizieR/J/AJ/147/7
Title:
Photometry and spectroscopy of NGC 6520
Short Name:
J/AJ/147/7
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use CCD and photoelectric photometry with Stromgren filters along with medium resolution spectra to investigate NGC 6520, an open cluster very nearly in the direction of the galactic center. We find an age of 60Myr, a distance of 2kpc, and an average reddening E(b-y)=0.295, which increases toward the south. The average heliocentric radial velocity of the B stars is -29km/s, while the velocity of the nearby Barnard 86 is about 0 (heliocentric; -11km/s compared to the LSR). This velocity difference amounts to about 1.8kpc since the cluster formed, implying that it is extremely doubtful NGC6520 is related to Barnard 86.

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