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831. NIR APOGEE radial velocities of Draco C1
ID:
ivo://CDS.VizieR/J/ApJ/900/L43
Title:
NIR APOGEE radial velocities of Draco C1
Short Name:
J/ApJ/900/L43
Date:
15 Feb 2022 00:49:05
Publisher:
CDS
Description:
Draco C1 is a known symbiotic binary star system composed of a carbon red giant and a hot, compact companion-likely a white dwarf-belonging to the Draco dwarf spheroidal galaxy. From near-infrared spectroscopic observations taken by the Apache Point Observatory Galactic Evolution Experiment (APOGEE-2), part of Sloan Digital Sky Survey IV, we provide updated stellar parameters for the cool, giant component, and constrain the temperature and mass of the hot, compact companion. Prior measurements of the periodicity of the system, based on only a few epochs of radial velocity data or relatively short baseline photometric observations, were sufficient only to place lower limits on the orbital period (P>300d). For the first time, we report precise orbital parameters for the binary system: with 43 radial velocity measurements from APOGEE spanning an observational baseline of more than 3yr, we definitively derive the period of the system to be 1220.0_-3.5_^+3.7^days. Based on the newly derived orbital period and separation of the system, together with estimates of the radius of the red giant star, we find that the hot companion must be accreting matter from the dense wind of its evolved companion.
832. NIR H lines in TTS
ID:
ivo://CDS.VizieR/J/A+A/365/90
Title:
NIR H lines in TTS
Short Name:
J/A+A/365/90
Date:
21 Oct 2021
Publisher:
CDS
Description:
Paschen {beta} and/or Bracket {gamma} emission line profiles were obtained for a sample of 50 T Tauri stars mostly from the Taurus-Auriga complex. The tables presented here contain the computed line parameters of the observed line profiles.
833. NIR imaging of HH 223
ID:
ivo://CDS.VizieR/J/A+A/523/A16
Title:
NIR imaging of HH 223
Short Name:
J/A+A/523/A16
Date:
21 Oct 2021
Publisher:
CDS
Description:
The dark cloud Lynds 723 (L723) is a low-mass star-forming region where one of the few known cases of a quadrupolar CO outflow has been reported. Two recent works have found that the radio continuum source VLA 2, towards the centre of the CO outflow, is actually a multiple system of young stellar objects (YSOs). We imaged a field of 5'x 5' centred on HH 223, which includes the whole region of the quadrupolar CO outflow with narrow-band filters centred on the [FeII] 1.644mum and H_2_ 2.122mum lines, together with off-line H_c_ and K_c_ filters. Our aim is to study L723 in the near-infrared and look for line-emission nebulae associated with the optical and CO outflows.
834. NIR knots in the Cas A supernova remnant
ID:
ivo://CDS.VizieR/J/ApJ/837/118
Title:
NIR knots in the Cas A supernova remnant
Short Name:
J/ApJ/837/118
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of broadband (0.95-2.46{mu}m) near-infrared spectroscopic observations of the Cassiopeia A supernova remnant. Using a clump-finding algorithm in two-dimensional dispersed images, we identify 63 "knots" from eight slit positions and derive their spectroscopic properties. All of the knots emit [FeII] lines together with other ionic forbidden lines of heavy elements, and some of them also emit H and He lines. We identify 46 emission line features in total from the 63 knots and measure their fluxes and radial velocities. The results of our analyses of the emission line features based on principal component analysis show that the knots can be classified into three groups: (1) He-rich, (2) S-rich, and (3) Fe-rich knots. The He-rich knots have relatively small, <~200km/s, line-of-sight speeds and radiate strong He I and [FeII] lines resembling closely optical quasi-stationary flocculi of circumstellar medium, while the S-rich knots show strong lines from O-burning material with large radial velocities up to ~2000km/s indicating that they are supernova ejecta material known as fast-moving knots. The Fe-rich knots also have large radial velocities but show no lines from O-burning material. We discuss the origin of the Fe-rich knots and conclude that they are most likely "pure" Fe ejecta synthesized in the innermost region during the supernova explosion. The comparison of [FeII] images with other waveband images shows that these dense Fe ejecta are mainly distributed along the southwestern shell just outside the unshocked ^44^Ti in the interior, supporting the presence of unshocked Fe associated with ^44^Ti.
835. NIR long-slit spectra of Seyfert galaxies
ID:
ivo://CDS.VizieR/J/A+A/560/A99
Title:
NIR long-slit spectra of Seyfert galaxies
Short Name:
J/A+A/560/A99
Date:
21 Oct 2021
Publisher:
CDS
Description:
The excitation of the gas phase of the interstellar medium can be driven by various mechanisms. In galaxies with an active nucleus, such as Seyfert galaxies, both radiative and mechanical energy from the central black hole, or the stars in the disk surrounding it may play a role. We investigate the relative importance and range of influence of the active galactic nucleus for the excitation of ionized and molecular gas in the central kiloparsec of its host galaxy. We present H- and K-band long-slit spectra for a sample of 21 nearby (D<70Mpc) Seyfert galaxies obtained with the NIRSPEC instrument on the Keck telescope. For each galaxy, we fit the nebular line emission, stellar continua, and warm molecular gas as a function of distance from the nucleus.
836. NIR observations of sources in galactic center
ID:
ivo://CDS.VizieR/J/A+A/499/483
Title:
NIR observations of sources in galactic center
Short Name:
J/A+A/499/483
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a study that uses AO assisted observations obtained at the ESO VLT in the NIR H-band and 7 intermediate bands covering the NIR K-band. A comparison of the resulting SEDs with a blackbody of variable extinction then allows us to determine the presence and strength of a CO absorption feature to distinguish between early and late type stars. This new method is suitable for classifying K giants (and later), as well as B2 main sequence (and earlier) stars that are brighter than 15.5mag in the K band in the central parsec. Extremely red objects and foreground sources can also be reliably removed from the sample. Several results, such as the shape of the KLF and the spatial distribution of both early and late type stars, confirm and extend previous works. The distribution of the early type stars can be fitted with a steep power law (beta_1"_=-1.49+/-0.12), alternatively with a broken power law, beta_1-10"_=-1.08+/-0.12, beta_10-20"_=-3.46+/-0.58, since we find a drop in the early type density at ~10". We also detect early type candidates outside of 0.5pc in significant numbers for the first time. The late type density function shows an inversion in the inner 6", with a power-law slope of beta_R<6"_=0.17+/-0.09. The late type KLF has a power-law slope of 0.30+/-0.01, closely resembling the KLF obtained for the bulge of the Milky Way. The early type KLF has a much flatter slope of (0.14+/-0.02). Our results agree best with an in-situ star formation scenario.
837. NIR observations of stars near SgrA*
ID:
ivo://CDS.VizieR/J/A+A/511/A18
Title:
NIR observations of stars near SgrA*
Short Name:
J/A+A/511/A18
Date:
21 Oct 2021
Publisher:
CDS
Description:
The nuclear star cluster of the Galaxy is an important template for understanding its extragalactic counterparts, which can currently not be resolved into individual stars. Important drawbacks of observations of the Galactic center are, however, the presence of strong and spatially highly variable interstellar extinction and extreme crowding of the sources, which makes the use of adaptive optics techniques necessary. Both points pose serious obstacles to precise photometry that is needed for analyzing the stellar population. The aims of this work are to provide accurate photometry in multiple near-infrared broadband filters, to determine the power-law index of the extinction-law toward the central parsec of the Galaxy, to provide measurements of the absolute extinction toward the Galactic center, and finally to measure the spatial variability of extinction on arcsecond scales.
838. NIR obs. of X-ray AGNs in COSMOS, SXDS & E-CDF-S
ID:
ivo://CDS.VizieR/J/ApJS/239/22
Title:
NIR obs. of X-ray AGNs in COSMOS, SXDS & E-CDF-S
Short Name:
J/ApJS/239/22
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present near-IR spectroscopy in the J- and H-bands for a large sample of 243 X-ray-selected, moderate-luminosity Type 1 active galactic nuclei (AGNs) in the COSMOS, SXDS, and E-CDF-S survey fields using the multi-object spectrograph Subaru/FMOS. Our sample covers the redshift range 0.5<=z<=3.0 and X-ray luminosity range of 10^43^<=L_[2-10keV]_<=10^45^erg/s. We provide emission-line properties and derived virial black hole mass estimates, bolometric luminosities, and Eddington ratios, based on H{alpha} (211), H{beta} (63), and MgII (4). We compare line widths, luminosities, and black hole mass estimates from H{alpha} and H{beta}, and augment these with commensurate measurements of MgII and CIV detected in optical spectra. We demonstrate the robustness of using H{alpha}, H{beta}, and MgII as reliable black hole mass estimators for high-z moderate-luminosity AGNs, while the use of CIV is prone to large uncertainties (>=0.4dex). We extend a recently proposed correction based on the CIV blueshift to lower luminosities and black hole masses. While our sample shows an improvement in their CIV black hole mass estimates, the deficit of high blueshift sources reduces its overall importance for moderate-luminosity AGNs compared to the most luminous quasars. In addition, we revisit luminosity correlations between Lbol, L_[2-10keV]_, L[OIII], L5100, and LH{alpha} and find them to be consistent with a simple empirical model, based on a small number of well-established scaling relations. Finally, we highlight our highest redshift AGN, CID 781, at z=4.6, which has the lowest black hole mass (~10^8^M_{sun}_) among current near-IR samples at this redshift and is in a state of fast growth.
839. NIR photometry of IRAS sources. III
ID:
ivo://CDS.VizieR/J/A+AS/126/479
Title:
NIR photometry of IRAS sources. III
Short Name:
J/A+AS/126/479
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the near infrared photometry of a new sample of 225 IRAS sources, many of them previously unidentified in the literature, selected because their far infrared colours are similar to those shown by known planetary nebulae. The results obtained are used to establish the main source of near infrared emission. Combining this information with the far infrared IRAS data and a few additional criteria we determine the nature and evolutionary stage of all the sources observed so far, including those for which near infrared photometry was previously reported in Papers I (Manchado et al., 1989A&A...214..139M) and II (Garcia-Lario et al., 1990A&AS...82..497G).
840. NIR polarimetry in the Central Molecular Zone
ID:
ivo://CDS.VizieR/J/ApJS/213/22
Title:
NIR polarimetry in the Central Molecular Zone
Short Name:
J/ApJS/213/22
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out near-infrared polarimetry toward the boundary of the Central Molecular Zone, in the field of (-1.{deg}4<~l<~-0.{deg}3 and 1.{deg}0<~l<~2.{deg}9,|b|<~0.{deg}1), using the near-infrared polarimetric camera SIRPOL on the 1.4m Infrared Survey Facility telescope. We have selected 112 intrinsically polarized sources on the basis of the estimate of interstellar polarization on Stokes Q/I-U/I planes. The selected sources are brighter than K_S_=14.5mag and have polarimetric uncertainty {delta}P<1%. Ten of these distinctive polarized sources are fit well with spectral energy distributions of young stellar objects when using the photometry in the archive of the Spitzer Space Telescope mid-infrared data. However, many sources have spectral energy distributions of normal stars suffering from heavy interstellar extinction; these might be stars behind dark clouds. Due to the small number of distinctive polarized sources and candidates of young stellar objects, we cannot judge if they are declining in number outside the Central Molecular Zone. Many massive candidates for young stellar objects in the literature have only small intrinsic polarization. This might suggest that their masses are 4-15M_{sun}_, whose intrinsic polarization has been expected to be small.