- ID:
- ivo://CDS.VizieR/J/A+A/631/A91
- Title:
- 2 strongly lensed galaxies MUSE & ALMA datacubes
- Short Name:
- J/A+A/631/A91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compare the molecular and ionized gas kinematics of two strongly lensed galaxies at z~1 that lie on the main sequence at this redshift, based on observations from ALMA and MUSE, respectively. We derive the CO and [OII] rotation curves and dispersion profiles of these two galaxies. We find a difference between the observed molecular and ionized gas rotation curves for one of the two galaxies, the Cosmic Snake, for which we obtain a spatial resolution of few hundred parsecs along the major axis. The rotation curve of the molecular gas is steeper than the rotation curve of the ionized gas. In the second galaxy, A521, the molecular and ionized gas rotation curves are consistent, but the spatial resolution is only of few kpc on the major axis. Using simulations, we investigate the effect of the thickness of the gas disk and effective radius on the observed rotation curves and find that a more extended and thicker disk smooths the curve. We also find that the presence of a strongly inclined (>70{deg}) thick disk (>1kpc) can smooth the rotation curve because it degrades the spatial resolution along the line of sight. By building a model using a stellar disk and two gas disks, we reproduce the rotation curves of the Cosmic Snake with a molecular gas disk that is more massive and more radially and vertically concentrated than the ionized gas disk. Finally, we also obtain an intrinsic velocity dispersion in the Cosmic Snake of 18.5+/-7km/s and 19.5+/-6km/s for the molecular and ionized gas, respectively, which is consistent with a molecular disk with a smaller and thinner disk. For A521, the intrinsic velocity dispersion values are 11+/-8km/s and 54+/-11km/s, with a higher value for the ionized gas. This could indicate that the ionized gas disk is thicker and more turbulent in this galaxy. These results highlight the diversity of the kinematics of galaxies at z~1 and the different spatial distribution of the molecular and ionized gas disks. It suggests the presence of thick ionized gas disks at this epoch and that the formation of the molecular gas is limited to the midplane and center of the galaxy in some objects.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/608/A144
- Title:
- Strongly lensed submm galaxies CO spectra
- Short Name:
- J/A+A/608/A144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the IRAM-30m observations of multiple-J CO (J_up_ mostly from 3 up to 8) and [CI](^3^P_2_ -> ^3^P_1_) ([CI](2-1) hereafter) line emission in a sample of redshift ~2-4 submillimeter galaxies (SMGs). These SMGs are selected among the brightest lensed galaxies discovered in the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS). 47 CO lines and 7 [CI](2-1) lines have been detected in 15 lensed SMGs. A non-negligible effect of differential lensing is found for the CO emission lines, which could have caused significant underestimations of the linewidths, hence of the dynamical masses. The CO spectral line energy distributions (SLEDs), peaking around J_up_~5-7, are found to be similar to those of the local starburst-dominated ultra-luminous infrared galaxies and of the previously studied SMGs. After correcting for lensing amplification, we derived the global properties of the bulk of molecular gas in the SMGs using non-LTE radiative transfer modelling, such as the molecular gas density n_H2_~10^2.5^-10^4.1^cm^-3^ and the kinetic temperature T_k_~20-750K. The gas thermal pressure P_{th} ranging from ~10^5^K/cm^3^ to 10^6^K/cm^3^ is found to be correlated with star formation efficiency. Further decomposing the CO SLEDs into two excitation components, we find a low-excitation component with n_H2_~10^2.8^-10^4.6^cm^-3^ and T_k_~20-30K, which is less correlated with star formation, and a high-excitation one (n_H2_~10^2.7^-10^4.2^cm^-3^, T_k_~60-400K) which is tightly related to the on-going star-forming activity. Additionally, tight linear correlations between the far-infrared and CO line luminosities have been confirmed for the J_up_>=5 CO lines of these SMGs, implying that these CO lines are good tracers of star formation. The [CI](2-1) lines follow the tight linear correlation between the luminosities of the [CI](2-1) and the CO(1-0) line found in local starbursts, indicating that [CI] lines could serve as good total molecular gas mass tracers for high-redshift SMGs as well. The total mass of the molecular gas reservoir, (1-30)x10^10^M_{sun}_, derived based on the CO(3-2) fluxes and {alpha}_CO(1-0)_=0.8M_{sun}_/(K.km/s/pc^2), suggests a typical molecular gas depletion time t_dep_~20-100Myr and a gas to dust mass ratio {delta}_GDR_~30-100 with ~20%-60% uncertainty for the SMGs. The ratio between CO line luminosity and the dust mass L'_CO(1-0)_/M_{dust} appears to be slowly increasing with redshift for high-redshift SMGs, which CO need to be further confirmed by a more complete SMG sample at various redshifts. Finally, through comparing the linewidth of CO and H_2_O lines, we find that they agree well in almost all our SMGs, confirming that the emitting regions of the CO and H_2_O lines are co-spatially located.
- ID:
- ivo://CDS.VizieR/J/ApJ/739/L44
- Title:
- Structural data for galaxies between 0.2<z<2.7
- Short Name:
- J/ApJ/739/L44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the size growth seen in early-type galaxies over 10Gyr of cosmic time. Our analysis is based on a homogeneous synthesis of published data from 16 spectroscopic surveys observed at similar spatial resolution, augmented by new measurements for galaxies in the Gemini Deep Deep Survey. In total, our sample contains structural data for 465 galaxies (mainly early-type) in the redshift range 0.2<z<2.7. The size evolution of passively evolving galaxies over this redshift range is gradual and continuous, with no evidence for an end or change to the process around z~1, as has been hinted at by some surveys which analyze subsets of the data in isolation. The size growth appears to be independent of stellar mass, with the mass-normalized half-light radius scaling with redshift as R_e_{propto}(1+z)^-1.62+/-0.34^. Surprisingly, this power law seems to be in good agreement with the recently reported continuous size evolution of UV-bright galaxies in the redshift range z~0.5-3.5. It is also in accordance with the predictions from recent theoretical models.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/L50
- Title:
- Structure of the Upper Scorpius association
- Short Name:
- J/MNRAS/477/L50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using new proper motion data from recently published catalogs, we revisit the membership of previously identified members of the Upper Scorpius association. We confirmed 750 of them as cluster members based on the convergent point method, compute their kinematic parallaxes and combined them with Gaia parallaxes to investigate the 3D structure and geometry of the association using a robust covariance method. We find a mean distance of 146+/-3+/-6pc and show that the morphology of the association defined by the brightest (and most massive) stars yields a prolate ellipsoid with dimensions of 74x38x32pc^3^, while the faintest cluster members define a more elongated structure with dimensions of 98x24x18pc^3^. We suggest that the different properties of both populations is an imprint of the star formation history in this region.
- ID:
- ivo://CDS.VizieR/J/AZh/80/704
- Title:
- Studies of classical barium stars
- Short Name:
- J/AZh/80/704
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The abundances of chemical elements in the atmospheres of seven classical barium stars are derived.
- ID:
- ivo://CDS.VizieR/J/AJ/157/111
- Title:
- Study of three early-type contact twin binaries
- Short Name:
- J/AJ/157/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Three eclipsing binaries, CT Tau, GU Mon, and V701 Sco, are early-type contact binaries with infrared excess from circumbinary matter. We present the multi-color photometry for CT Tau and GU Mon, whose spectral types of B1V are identified by the low-precision spectra. Combining these new light curves (LCs) with previously reported LCs and radial velocity curves, we perform a synthesized analysis to estimate/update the stellar absolute parameters of the three systems. Their mass ratios are close to unity (i.e., q~1), which indicates that the binary system comprising of twin components may be undergoing a slow Case A mass transfer. From the period analysis, the light-time orbit in the (O-C) curve may result from the third condense companion around the binary system although no evidence could be provided by the third light l_3_. From the spectral energy distribution for three binaries, the excess infrared (IR) emissions are above the photospheric emissions, which can be seen at the 22.1 {mu}m for CT Tau and GU Mon, and 11.6 {mu}m, 14.5 {mu}m, and 22.1 {mu}m for V701 Sco, respectively. This kind of infrared excess for the early-type star may be attributed to the circumbinary matter by stellar wind.
2727. Study of Two HgMn Stars
- ID:
- ivo://CDS.VizieR/J/AZh/71/588
- Title:
- Study of Two HgMn Stars
- Short Name:
- J/AZh/71/588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Three spectra of HD182308 (HR 7361) and four spectra of HD178065 (HR 7245) were obtained from 1989 to 1990 with the Main Stellar Spectrograph of the 6-m telescope at the Special Astrophysical Observatory and with the Coude spectrograph of the 2-m telescope of the Rozhen Observatory of the Bulgarian Academy of Sciences. Spectra were obtained in the range of 3700-4900A with inverse dispersion of 9 A/mm. Spectral resolution was close to 0.25A. Elemental abundances of two HgMn stars, HD 178065 and HD 182308, were found. Objects: --------------------------------------- RA (2000) DE Designation(s) --------------------------------------- 19 19 46.03 +64 23 26.7 HD 182308 19 07 08.95 +00 38 29.3 HD 178065 ---------------------------------------
- ID:
- ivo://CDS.VizieR/J/ApJ/882/L22
- Title:
- Subaru obs. of Vesta in MIR spectral range
- Short Name:
- J/ApJ/882/L22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Plagioclase feldspars are among the most prevalent minerals in the solar system, and are present in many chondritic and achondritic meteorite families. Nevertheless, spectral features of plagioclases have never been unambiguously and directly observed in remote observations of asteroids. We report here the detection of an absorption band at 12.2{mu}m on Vesta spectra provided by ground-based spectral observations at the Subaru Telescope. This signature represents the first direct evidence of a widespread presence of crystalline Ca-rich plagioclase on Vesta and reveals that its regolith is comminuted to a very fine grain size, smaller than a few tens of microns, indicating that the mechanical brecciation process has been very effective. The crystalline nature of plagioclase strongly suggests that impacts alone cannot be the sole mechanism for regolith formation on Vesta and a milder process, such as thermal fatigue, should be invoked as an important and concomitant process Thermal fatigue should be considered a very effective process in regolith production and rejuvenation not only for near-Earth asteroids but even for large asteroids located in the main belt.
- ID:
- ivo://CDS.VizieR/J/ApJS/179/124
- Title:
- Subaru/XMM-Newton deep survey (SXDS) III.
- Short Name:
- J/ApJS/179/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the X-ray source catalog in the Subaru/XMM-Newton deep survey. A continuous area of 1.14deg^2^ centered at RA=02h18m and DE=-05{deg} is mapped by seven pointings with XMM-Newton covering the 0.2-10keV band. From the combined images of the EPIC pn and MOS cameras, we detect 866, 1114, 645, and 136 sources with sensitivity limits of 6x10^-16^, 8x10^-16^, 3x10^-15^, and 5x10^-15^ergs/cm^2^/s in the 0.5-2, 0.5-4.5, 2-10, and 4.5-10keV bands, respectively, with detection likelihood >=7 (corresponding to a confidence level of 99.91%). The catalog consists of 1245 sources in total including 32 extended-source candidates. The averaged logN-logS relations are in good agreement with previous results, bridging the flux range between Chandra deep surveys and brighter surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/540/A51
- Title:
- Submm spectrum of deuterated glycolaldehydes
- Short Name:
- J/A+A/540/A51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Glycolaldehyde, a sugar-related interstellar prebiotic molecule, has recently been detected in two star-forming regions, Sgr B2(N) and G31.41+0.31. The detection of this new species increased the list of complex organic molecules detected in the interstellar medium (ISM) and adds another level to the chemical complexity present in space. Besides, this kind of organic molecule is important because it is directly linked to the origin of life. For many years, astronomers have been struggling to understand the origin of this high chemical complexity in the ISM. The study of deuteration may provide crucial hints.
