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981. H band stellar spectra
ID:
ivo://CDS.VizieR/J/A+AS/116/239
Title:
H band stellar spectra
Short Name:
J/A+AS/116/239
Date:
21 Oct 2021
Publisher:
CDS
Description:
A sample of 37 stars of luminosity classes I, III, V, including few SMR stars observed in the H band with a medium resolution (R=1500-2000) is presented. This sample of flux calibrated spectra is intended to widen existing stellar libraries. Observations were conducted with the ISIS spectrograph at CFHT and with IRSPEC at ESO-NTT. The wavelength range covers 1.573-1.646 micron at NTT (R=1490 at 1.60micron) and 1.578-1.642 micron at CFHT (R=2000 at 1.60micron). Spectra are in relative fluxes, F(lambda), normalized to 1 in the range 1.59290-1.59506 micron. In the few cases where a star was observed both with ISIS and IRSPEC, both spectra are given. So the number of files is in fact 41 concerning 37 stars.
982. H{beta} to N2 line fluxes of nearby galaxies
ID:
ivo://CDS.VizieR/J/ApJ/847/136
Title:
H{beta} to N2 line fluxes of nearby galaxies
Short Name:
J/ApJ/847/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present calibrations for star formation rate (SFR) indicators in the ultraviolet, mid-infrared, and radio-continuum bands, including one of the first direct calibrations of 150MHz as an SFR indicator. Our calibrations utilize 66 nearby star-forming galaxies with Balmer-decrement-corrected H{alpha} luminosities, which span five orders of magnitude in SFR and have absolute magnitudes of -24<M_r_{<}-12. Most of our photometry and spectrophotometry are measured from the same region of each galaxy, and our spectrophotometry has been validated with SDSS photometry, so our random and systematic errors are small relative to the intrinsic scatter seen in SFR indicator calibrations. We find that the Wide-field Infrared Space Explorer W4 (22.8{mu}m), Spitzer 24{mu}m, and 1.4GHz bands have tight correlations with the Balmer-decrement-corrected H{alpha} luminosity, with a scatter of only 0.2dex. Our calibrations are comparable to those from the prior literature for L* galaxies, but for dwarf galaxies, our calibrations can give SFRs that are far greater than those derived from most previous literature.
983. HCN and CN emission in Serpens Main region
ID:
ivo://CDS.VizieR/J/A+A/656/A146
Title:
HCN and CN emission in Serpens Main region
Short Name:
J/A+A/656/A146
Date:
21 Mar 2022 09:00:12
Publisher:
CDS
Description:
Ultraviolet radiation (UV) influences the physics and chemistry of star-forming regions, but its properties and significance in the immediate surroundings of low-mass protostars are still poorly understood. We aim to extend the use of the CN/HCN ratio, already established for high-mass protostars, to the low-mass regime to trace and characterize the UV field around low-mass protostars on ~0.6x0.6pc scales. The spatial distribution of HCN and CS are well-correlated with CO 6-5 emission that traces outflows. The CN emission is extended from the central protostars to their immediate surroundings also tracing outflows, likely as a product of HCN photodissociation. The ratio of CN to HCN total column densities ranges from ~1 to 12 corresponding to G_0_~10^1^-10^3^ for gas densities and temperatures typical for outflows of low-mass protostars. UV radiation associated with protostars and their outflows is indirectly identified in a significant part of the Serpens Main low-mass star-forming region. Its strength is consistent with the values obtained from the OH and H_2_O ratios observed with Herschel and compared with models of UV-illuminated shocks. From a chemical viewpoint, the CN to HCN ratio is an excellent tracer of UV fields around low- and intermediate-mass star-forming regions.
984. HC_3_N in Orion KL
ID:
ivo://CDS.VizieR/J/A+A/559/A51
Title:
HC_3_N in Orion KL
Short Name:
J/A+A/559/A51
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of cyanoacetylene (HC_3_N) and cyanodiacetylene (HC_5_N) in Orion KL, using observations from two line surveys performed with the IRAM 30-m telescope and the HIFI instrument onboard the Herschel telescope. The frequency ranges covered are 80-280GHz and 480-1906GHz. This study (divided by families of molecules) is part of a global analysis of the physical conditions of Orion KL and the molecular abundances in the different components of this cloud. We modeled the observed lines of HC_3_N, HC_5_N, their isotopologues (including DC_3_N), and vibrational modes using a non-local thermodynamic equilibrium (non-LTE) radiative transfer code. In addition, to investigate the chemical origin of HC_3_N and DC_3_N in Orion KL, we used a time-dependent chemical model.
985. HCO and CH_3_O in prestellar cores
ID:
ivo://CDS.VizieR/J/A+A/587/A130
Title:
HCO and CH_3_O in prestellar cores
Short Name:
J/A+A/587/A130
Date:
21 Oct 2021
Publisher:
CDS
Description:
The recent unexpected detection of terrestrial complex organic molecules in the cold (~10K) gas has cast doubts on the commonly accepted formation mechanisms of these species. Standard gas-phase mechanisms are inefficient and tend to underproduce these molecules, and many of the key reactions involved are unconstrained. Grain-surface mechanisms, which were presented as a viable alternative, suffer from the fact that they rely on grain surface diffusion of heavy radicals, which is not possible thermally at very low temperatures. One of the simplest terrestrial complex organic molecules, methanol is believed to form on cold grain surfaces following from successive H atom additions on CO. Unlike heavier species, H atoms are very mobile on grain surfaces even at 10K. Intermediate species involved in grain surface methanol formation by CO hydrogenation are the radicals HCO and CH_3_O, as well as the stable species formaldehyde H_2_CO. These radicals are thought to be precursors of complex organic molecules on grain surfaces. We present new observations of the HCO and CH_3_O radicals in a sample of prestellar cores and carry out an analysis of the abundances of the species HCO, H_2_CO, CH_3_O, and CH_3_OH, which represent the various stages of grain- surface hydrogenation of CO to CH_3_OH. The abundance ratios between the various intermediate species in the hydrogenation reaction of CO on grains are similar in all sources of our sample, HCO:H_2_CO:CH_3_O:CH_3_OH~10:100:1:100. We argue that these ratios may not be representative of the primordial abundances on the grains but, rather, suggest that the radicals HCO and CH_3_O are gas-phase products of the precursors H_2_CO and CH_3_OH, respectively. Various gas-phase pathways are considered, including neutral-neutral and ion-molecule reactions, and simple estimates of HCO and CH_3_O abundances are compared to the observations. Critical reaction rate constants, branching ratios, and intermediate species are finally identified.
986. HCOOCH_2_D detection in Orion KL
ID:
ivo://CDS.VizieR/J/ApJ/779/119
Title:
HCOOCH_2_D detection in Orion KL
Short Name:
J/ApJ/779/119
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on new measurements carried out in the laboratory from 0.77 to 1.2THz and on a line-frequency analysis of these new data, along with previously published data, we build a line list for HCOOCH_2_D that leads to its first detection in the Orion KL nebula. The observed lines, both in space and in the laboratory, involve the cis D-in-plane and trans D-out-of-plane conformations of HCOOCH_2_D and the two tunneling states arising from the large-amplitude motion connecting the two trans configurations. The model used in the line position calculation accounts for both cis and trans conformations, as well as the large-amplitude motion.
987. hCOSMOS: Hectospec survey of galaxies in COSMOS
ID:
ivo://CDS.VizieR/J/ApJS/234/21
Title:
hCOSMOS: Hectospec survey of galaxies in COSMOS
Short Name:
J/ApJS/234/21
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the hCOSMOS redshift survey of the COSMOS field conducted with the Hectospec spectrograph on the MMT. In the central 1deg^2^, the hCOS20.6 subset of the survey is >90% complete to a limiting magnitude r=20.6. The hCOSMOS survey includes 1701 new redshifts in the COSMOS field. We also use the total of 4362 new and remeasured objects to derive the age-sensitive D_n_4000 index over the entire redshift interval 0.001<~z<~0.6. For 85% of the quiescent galaxies in hCOS20.6, we measure the central line-of-sight velocity dispersion. To explore potential uses of this survey, we combine previously measured galaxy sizes, profiles, and stellar masses with the spectroscopy. The comparison reveals the known relations among structural, kinematic, and stellar population properties. We also compare redshift and D_n_4000 distributions of hCOS20.6 galaxies with SHELS; a complete spectroscopic survey of 4deg^2^ observed to the same depth. The redshift distributions in the two fields are very different, but the D_n_4000 distribution is remarkably similar. The relation between velocity dispersion and stellar mass for massive hCOS20.6 galaxies is consistent with the local relation from the Sloan Digital Sky Survey. Using measured velocity dispersions, we test a photometric proxy calibrated to galaxies in the local universe. The systematic differences between the measured and photometric proxy velocity dispersions are correlated with galaxy dynamical and stellar population properties highlighting the importance of direct spectroscopic measurements.
988. HD 285507 and AD Leo light and velocity curves
ID:
ivo://CDS.VizieR/J/A+A/638/A5
Title:
HD 285507 and AD Leo light and velocity curves
Short Name:
J/A+A/638/A5
Date:
21 Oct 2021
Publisher:
CDS
Description:
The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the proto-planetary disk or the circularization of an initial high eccentric orbit by tidal dissipation leading to a strong decrease of the semimajor axis. Different formation scenarios result in different observable effects, such as orbital parameters (obliquity/eccentricity), or frequency of planets at different stellar ages. In the context of the GAPS Young-Objects project, we are carrying out a radial velocity survey with the aim to search and characterize young hot-Jupiter planets. Our purpose is to put constraints on evolutionary models and establish statistical properties, such as the frequency of these planets from a homogeneous sample. Since young stars are in general magnetically very active, we performed multi-band (visible and near-infrared) spectroscopy with simultaneous GIANO-B + HARPS-N (GIARPS) observing mode at TNG. This helps to deal with stellar activity and distinguish the nature of radial velocity variations: stellar activity will introduce a wavelength-dependent radial velocity amplitude, whereas a Keplerian signal is achromatic. As a pilot study, we present here the cases of two already claimed hot Jupiters orbiting young stars: HD 285507 b and AD Leo b. Our analysis of simultaneous high-precision GIARPS spectroscopic data confirms the Keplerian nature of HD285507's radial velocities variation and refines the orbital parameters of the hot Jupiter, obtaining an eccentricity consistent with a circular orbit. On the other hand, our analysis does not confirm the signal previously attributed to a planet orbiting AD~Leo. This demonstrates the power of the multi-band spectroscopic technique when observing active stars.
989. HD 209458 and HD 189733 theoretical spectra
ID:
ivo://CDS.VizieR/J/A+A/539/A102
Title:
HD 209458 and HD 189733 theoretical spectra
Short Name:
J/A+A/539/A102
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare limb darkening laws derived from 3D hydrodynamical model atmospheres and 1D hydrostatic MARCS models for the host stars of two well-studied transiting exoplanet systems, the late-type dwarfs HD 209458 and HD 189733. The surface brightness distribution of the stellar disks is calculated for a wide spectral range using 3D LTE spectrum formation and opacity sampling. We test our theoretical predictions using least-squares fits of model light curves to wavelength-integrated primary eclipses that were observed with the Hubble Space Telescope (HST).
990. HD 146850 atomic lines
ID:
ivo://CDS.VizieR/J/A+A/297/503
Title:
HD 146850 atomic lines
Short Name:
J/A+A/297/503
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the identification of 3 Li-rich giants discovered in an ongoing survey based on IRAS colours. A detailed analysis of one of these, HD 146850, is presented here. High resolution spectra were obtained for this star, using CASPEC at the 3.6m telescope of ESO.

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