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1811. NH_3_ line lists at high temperatures
ID:
ivo://CDS.VizieR/J/ApJ/735/111
Title:
NH_3_ line lists at high temperatures
Short Name:
J/ApJ/735/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present line lists for ammonia (NH_3_) at high temperatures obtained by recording Fourier transform infrared emission spectra. Calibrated line lists are presented for 12 temperatures (300{deg}C-1300{deg}C in 100{deg}C intervals and 1370{deg}C) and each line list covers the 740-2100cm^-1^ range, which includes the majority of the {nu}_2_ umbrella bending mode region (11um) and the {nu}_4_ asymmetric bending mode region (6.2um). We also demonstrate the useful technique of obtaining empirical lower state energies from a set of spectra recorded at different sample temperatures. Using our NH_3_ spectra, we have estimated lower state energies (E_Low_ in cm^-1^) and our values have been incorporated into the line lists along with calibrated wavenumbers (\tilde{nu} in cm^-1^) and calibrated line intensities (S' in cm/molecule) for each line. We expect our hot NH_3_ line lists to find direct application in the modeling of planetary atmospheres and brown dwarfs.
1812. NH3 line profiles in star-forming regions
ID:
ivo://CDS.VizieR/J/ApJ/806/74
Title:
NH3 line profiles in star-forming regions
Short Name:
J/ApJ/806/74
Date:
21 Oct 2021
Publisher:
CDS
Description:
Anomalous ammonia (NH_3_) spectra, exhibiting asymmetric hyperfine satellite intensity profiles in the (J,K)=(1,1) inversion transition, have been observed in star-forming regions for over 35 years. We present a systematic study of this "hyperfine intensity anomaly" (HIA) toward a sample of 334 high-mass star forming regions: 310 high-mass (>~100M_{sun}_) clumps and 24 infrared dark clouds. The HIA is ubiquitous in high-mass star forming regions. Although LTE excitation predicts that the intensity ratios of the outer satellites and inner satellites are exactly unity, for this sample the ensemble average ratios are 0.812+/-0.004 and 1.125+/-0.005, respectively. We have quantified the HIA and find no significant relationships between the HIA and temperature, line width, optical depth, and the stage of stellar evolution. The fact that HIAs are common in high-mass star-forming regions suggests that the conditions that lead to HIAs are ubiquitous in these regions. A possible link between HIAs and the predictions of the competitive accretion model of high-mass star formation is suggested; however, the expected trends of HIA strength with clump evolutionary stage, rotational temperature, and line width for evolving cores in competitive accretion models are not found. Thus, the exact gas structures that produce HIAs remain unknown. Turbulent gas structures are a possible explanation, but the details need to be explored.
1813. NIBLES II. Arecibo follow-up observations
ID:
ivo://CDS.VizieR/J/A+A/596/A60
Title:
NIBLES II. Arecibo follow-up observations
Short Name:
J/A+A/596/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
We obtained Arecibo HI line follow-up observations of 154 of the 2600 galaxies in the Nancay Interstellar Baryons Legacy Extragalactic Survey (NIBLES) sample. These observations are on average four times more sensitive than the original observations at the Nancay Radio Telescope. The main goal of this survey is to characterize the underlying HI properties of the NIBLES galaxies which were undetected or marginally detected at Nancay. Of the Nancay non-detections, 85% were either clearly or marginally detected at Arecibo, while 89% of the Nancay marginal detections were clearly detected. Based on the statistics of the detections relative to g-i color and r-band luminosity (Lr) distribution among our Arecibo observations, we anticipate ~60% of our 867 Nancay non-detections and marginal detections could be detected at the sensitivity of our Arecibo observations. Follow-up observations of our low luminosity (Lr<10^8.5^L_{sun}_) blue sources indicate that they have, on average, more concentrated stellar mass distributions than the Nancay detections in the same luminosity range, suggesting we may be probing galaxies with intrinsically different properties. These follow-up observations enable us to probe HI mass fractions, log(MHI/M*) 0.5dex and 1dex lower, on average, than the NIBLES and ALFALFA surveys respectively.
1814. [NII]/H{alpha} ratio in galaxies with KMOS^3D^
ID:
ivo://CDS.VizieR/J/ApJ/827/74
Title:
[NII]/H{alpha} ratio in galaxies with KMOS^3D^
Short Name:
J/ApJ/827/74
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the [NII]/H{alpha} ratio as a probe of gas-phase oxygen abundance for a sample of 419 star-forming galaxies at z=0.6-2.7 from the KMOS^3D^ near-IR multi-integral field unit (IFU) survey. The mass-metallicity relation (MZR) is determined consistently with the same sample selection, metallicity tracer, and methodology over the wide redshift range probed by the survey. We find good agreement with long-slit surveys in the literature, except for the low-mass slope of the relation at z~2.3, where this sample is less biased than previous samples based on optical spectroscopic redshifts. In this regime we measure a steeper slope than some literature results. Excluding the contribution from active galactic nuclei from the MZR reduces sensitivity at the high-mass end, but produces otherwise consistent results. There is no significant dependence of the [NII]/H{alpha} ratio on star formation rate at fixed redshift and stellar mass. The IFU data allow spatially resolved measurements of [NII]/H{alpha}, from which we can infer abundance gradients for 180 galaxies, thus tripling the current sample in the literature. The observed gradients are on average flat, with only 15 gradients statistically offset from zero at >3{sigma}. We have modeled the effect of beam smearing, assuming a smooth intrinsic radial gradient and known seeing, inclination, and effective radius for each galaxy. Our seeing-limited observations can recover up to 70% of the intrinsic gradient for the largest, face-on disks, but only 30% for the smaller, more inclined galaxies. We do not find significant trends between observed or corrected gradients and any stellar population, dynamical, or structural galaxy parameters, mostly in agreement with existing studies with much smaller sample sizes. In cosmological simulations, strong feedback is generally required to produce flat gradients at high redshift.
1815. [NII] observations of the Carina Nebula (NGC 3372)
ID:
ivo://CDS.VizieR/J/ApJ/739/100
Title:
[NII] observations of the Carina Nebula (NGC 3372)
Short Name:
J/ApJ/739/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a ~250arcmin^2^ mapping of the 205um [NII] fine-structure emission over the northern Carina Nebula, including the Car I and Car II HII regions. Spectra were obtained using the South Pole Imaging Fabry-Perot Interferometer (SPIFI) at the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) at the South Pole. We supplement the 205um data with new reductions of far-IR fine-structure spectra from the Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) in 63um [OI], 122um [NII], 146um [OI], and 158um [CII]; the 146um [OI] data include 90 raster positions which have not been previously published. Morphological comparisons are made with optical, radio continuum, and CO maps. The 122/205 line ratio is used to probe the density of the low-ionization gas, and the 158/205 line ratio is used to probe the fraction of C^+^ arising from photodissociation regions (PDRs). The [OI] and [CII] lines are used to construct a PDR model of Carina. When the PDR properties are compared with other sources, Carina is found to be more akin to 30 Doradus than galactic star-forming regions such as Orion, M17, or W49; this is consistent with the view of Carina as a more evolved region, where much of the parent molecular cloud has been ionized or swept away. These data constitute the first ground-based detection of the 205um [NII] line, and the third detection overall since those of COBE FIRAS and the Kuiper Airborne Observatory in the early 1990s.
1816. [NII]205um emission in local luminous IR galaxies
ID:
ivo://CDS.VizieR/J/ApJ/819/69
Title:
[NII]205um emission in local luminous IR galaxies
Short Name:
J/ApJ/819/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we present the measurements of the [NII]205{mu}m line for a flux-limited sample of 122 (ultra-)luminous infrared galaxies [(U)LIRGs] and 20 additional normal galaxies, obtained with the Herschel Space Observatory (Herschel). We explore the far-infrared (FIR) color dependence of the [NII]205{mu}m (L_[NII]205{mu}m_) to the total infrared (L_IR_) luminosity ratio, and find that L_[NII]205{mu}m_/L_IR_ only depends modestly on the 70-160{mu}m flux density ratio (f70/f160) when f70/f160<~0.6, whereas such dependence becomes much steeper for f70/f160>0.6. We also investigate the relation between L_[NII]205{mu}m_ and star formation rate (SFR), and show that L_[NII]205{mu}m_ has a nearly linear correlation with SFR, albeit the intercept of such a relation varies somewhat with f60/f100, consistent with our previous conclusion that [NII]205{mu}m emission can serve as an SFR indicator with an accuracy of ~0.4dex, or ~0.2dex if f60/f100 is known independently. Furthermore, together with the Infrared Space Observatory measurements of [NII], we use a total of ~200 galaxies to derive the local [NII]205{mu}m luminosity function (LF) by tying it to the known IR LF with a bivariate method. As a practical application, we also compute the local SFR volume density ({rho}_SFR_) using the newly derived SFR calibrator and LF. The resulting log{rho}_SFR_=-1.96+/-0.11M_{sun}_/yr/Mpc^3^ agrees well with previous studies. Finally, we determine the electron densities (n_e_) of the ionized medium for a subsample of 12 (U)LIRGs with both [NII]205{mu}m and [NII]122{mu}m data, and find that n_e_ is in the range of ~1-100/cm^3^, with a median value of 22/cm^3^.
1817. 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.
1818. 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.
1819. 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.
1820. 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.

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