- ID:
- ivo://CDS.VizieR/J/A+A/494/977
- Title:
- HCO mapping of the Horsehead
- Short Name:
- J/A+A/494/977
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Far-UV photons (FUV) strongly affect the physical and chemical state of molecular gas in the vicinity of young massive stars. Finding molecular tracers of the presence of FUV radiation fields in the millimeter wavelength domain is desirable because IR diagnostics (for instance PAHs) are not easily accessible along high extinction line-of-sights. Furthermore, gas phase diagnostics provide information on the velocity fields.
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Search Results
- 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.
7963. HCOOCH3 map of Orion-KL
- ID:
- ivo://CDS.VizieR/J/A+A/532/A32
- Title:
- HCOOCH3 map of Orion-KL
- Short Name:
- J/A+A/532/A32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Orion Kleinmann-Low nebula (Orion-KL) is a complex region of star formation. Whereas its proximity allows studies on a scale of a few hundred AU, spectral confusion makes it difficult to identify molecules with low abundances. We studied an important oxygenated molecule, HCOOCH3, to characterize the physical conditions, temperature, and density of the different molecular source components.
- ID:
- ivo://CDS.VizieR/J/A+A/568/A58
- Title:
- HCOO^13^CH_3_ rotational spectrum
- Short Name:
- J/A+A/568/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An astronomical survey of interstellar molecular clouds needs a previous analysis of the spectra in the microwave and sub-mm energy range of organic molecules to be able to identify them. We obtained very accurate spectroscopic constants in a comprehensive laboratory analysis of rotational spectra. These constants can be used to predict the transitions frequencies very precisely that were not measured in the laboratory. We present the experimental study and its theoretical analysis for two ^13^C-methyl formate isotopologues to detect these two isotopologues for the first time in their excited torsional states, which lie at 130/cm (200K) in Orion-KL. New spectra of HCO-O-^13^CH_3_ (^13^C_2_) methyl formate were recorded with the mm- and submm-wave spectrometer in Lille from 50 to 940GHz. A global fit for v_t_=0 and 1 was accomplished with the BELGI program to reproduce the experimental spectra with greater accuracy. We analysed 5728 and 2881 new lines for v_t_=0 and 1 for HCOO^13^CH_3_. These new lines were globally fitted with 846 previously published lines for v_t_=0. In consequence, 52 parameters of the RAM Hamiltonian were accurately determined and the value of the barrier height (V_3_=369.93168(395)/cm) was improved. We report the detection of the first excited torsional states (v_t_=1) in Orion-KL for the ^13^C_2_ and ^13^C_1_ methyl formate based on the present analysis and previously published data. We provide column densities, isotopic abundances, and vibrational temperatures for these species. Following this work, accurate prediction can be provided. This permits detecting 135 features of the first excited torsional states of ^13^C-methyl formate isotopologues in Orion-KL in the 80-280GHz frequency range, without missing lines.
- ID:
- ivo://CDS.VizieR/J/A+A/605/A21
- Title:
- H_2_CO production in HD 163296
- Short Name:
- J/A+A/605/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the radial distribution of H_2_CO and C^18^O in the protoplanetary disk around HD 163296, a Herbig Ae type protostar, with the aim of determining possible formation scenarios of H_2_CO. By comparing the two molecules and the millimeter continuum, we investigate the relationship between the presence of H_2_CO and CO depletion in the disk.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/877/154
- Title:
- H_2_CO TMRT obs. of Galactic molecular clouds
- Short Name:
- J/ApJ/877/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of the C-band 1_10_-1_11_ (4.8GHz) and Ku-band 2_11_-2_12_ (14.5GHz) K-doublet lines of H_2_CO and the C-band 1_10_-1_11_ (4.6GHz) line of H_2_^13^CO toward a large sample of Galactic molecular clouds, through the Shanghai Tianma 65m radio telescope (TMRT). Our sample with 112 sources includes strong H_2_CO sources from the TMRT molecular line survey at C-band and other known H_2_CO sources. All three lines are detected toward 38 objects (43 radial velocity components) yielding a detection rate of 34%. Complementary observations of their continuum emission at both C- and Ku-bands were performed. Combining spectral line parameters and continuum data, we calculate the column densities, the optical depths and the isotope ratio H_2_^12^CO/H_2_^13^CO for each source. To evaluate photon trapping caused by sometimes significant opacities in the main isotopologue's rotational mm-wave lines connecting our measured K-doublets, and to obtain ^12^C/^13^C abundance ratios, we used the RADEX non-LTE model accounting for radiative transfer effects. This implied the use of the new collision rates from Wiesenfeld & Faure. Also implementing distance values from trigonometric parallax measurements for our sources, we obtain a linear fit of ^12^C/^13^C=(5.08+/-1.10)D_GC_+(11.86+/-6.60), with a correlation coefficient of 0.58. D_GC_ refers to Galactocentric distances. Our ^12^C/^13^C ratios agree very well with the ones deduced from CN and C^18^O but are lower than those previously reported on the basis of H_2_CO, tending to suggest that the bulk of the H_2_CO in our sources was formed on dust grain mantles and not in the gas phase.
7968. HD 110014
- ID:
- ivo://CDS.VizieR/J/A+A/504/617
- Title:
- HD 110014
- Short Name:
- J/A+A/504/617
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We found evidence for a sub-stellar companion around the K giant star HD 110014. This cool evolved star, with a spectral type K2III and an estimated mass between 1.9 and 2.4M_{sun}-, is slightly metal rich with [Fe/H]=0.19 and a rotational velocity Vsini=2.0km/s. ************************************************************************** * * * Sorry, but the author(s) never supplied the tabular material * * announced in the paper * * * **************************************************************************
- ID:
- ivo://CDS.VizieR/J/A+A/624/A33
- Title:
- HD 100453 AB system ALMA images
- Short Name:
- J/A+A/624/A33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complex system HD 100453 AB with a ring-like circumprimary disk and two spiral arms, one of which is pointing to the secondary, is a good laboratory in which to test spiral formation theories. We aim to resolve the dust and gas distribution in the disk around HD 100453 A and to quantify the interaction of HD 100453 B with the circumprimary disk. Using ALMA band 6 dust continuum and CO isotopologue observations we have studied the HD 100453 AB system with a spatial resolution of 0.09"x0.17" at 234GHz. We used smoothed particle hydrodynamics (SPH) simulations and orbital fitting to investigate the tidal influence of the companion on the disk. We resolve the continuum emission around HD 100453 A into a disk between 0.22" and 0.40" with an inclination of 29.5{deg} and a position angle of 151.0{deg}, an unresolved inner disk, and excess mm emission cospatial with the northern spiral arm which was previously detected using scattered light observations. We also detect CO emission from 7au (well within the disk cavity) out to 1.10", overlapping with HD 100453 B at least in projection. The outer CO disk position angle (PA) and inclination dier by up to 10{deg} from the values found for the inner CO disk and the dust continuum emission, which we interpret as due to gravitational interaction with HD 100453 B. Both the spatial extent of the CO disk and the detection of mm emission at the same location as the northern spiral arm are in disagreement with the previously proposed near co-planar orbit of HD 100453 B. We conclude that HD 100453 B has an orbit that is significantly misaligned with the circumprimary disk. Because it is unclear whether such an orbit can explain the observed system geometry we highlight an alternative scenario that explains all detected disk features where another, (yet) undetected, low mass close companion within the disk cavity, shepherds a misaligned inner disk whose slowly precessing shadows excite the spiral arms.
- 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.