- ID:
- ivo://CDS.VizieR/J/MNRAS/439/2701
- Title:
- Warm molecular hydrogen in ULIRGs
- Short Name:
- J/MNRAS/439/2701
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ultraluminous infrared galaxies (ULIRGs) show on average three times more emission in the rotational transitions of molecular hydrogen than expected based on their star formation rates. Using Spitzer archival data, we investigate the origin of excess warm H_2_ emission in 115 ULIRGs of the IRAS 1Jy sample. We find a strong correlation between H_2_ and [FeII] line luminosities, suggesting that excess H_2_ is produced in shocks propagating within neutral or partially ionized medium. This view is supported by the correlations between H_2_ and optical line ratios diagnostic of such shocks. The galaxies powered by star formation and those powered by active nuclei follow the same relationship between H_2_ and [FeII], with emission line width being the major difference between these classes (~500 and ~1000km/s, respectively). We conclude that excess H_2_ emission is produced as the supernovae and active nuclei drive outflows into the neutral interstellar medium of the ULIRGs. A weak positive correlation between H_2_ and the length of the tidal tails indicates that these outflows are more likely to be encountered in more advanced mergers, but there is no evidence for excess H_2_ produced as a result of the collision shocks during the final coalescence.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/160/230
- Title:
- WASP-31b and host star radius compared with IMACS
- Short Name:
- J/AJ/160/230
- Date:
- 10 Dec 2021
- Publisher:
- CDS
- Description:
- We present a new optical (400-950nm) transmission spectrum of the hot Jupiter WASP-31b (M=0.48M_Jup_; R=1.54R_Jup_; P=3.41days), obtained by combining four transit observations. These transits were observed with IMACS on the Magellan Baade Telescope at Las Campanas Observatory as part of the ACCESS project. We investigate the presence of clouds/hazes in the upper atmosphere of this planet, as well as the contribution of stellar activity on the observed features. In addition, we search for absorption features of the alkali elements NaI and KI, with particular focus on KI, for which there have been two previously published disagreeing results. Observations with Hubble Space Telescope (HST)/STIS detected KI, whereas ground-based low- and high- resolution observations did not. We use equilibrium and nonequilibrium chemistry retrievals to explore the planetary and stellar parameter space of the system with our optical data combined with existing near-IR observations. Our best-fit model is that with a scattering slope consistent with a Rayleigh slope ({alpha}=5.3_-3.1_^+2.9^), high-altitude clouds at a log cloud top pressure of -3.6_-2.1_^+2.7^bars, and possible muted H2O features. We find that our observations support other ground-based claims of no KI. Clouds are likely why signals like H2O are extremely muted and Na or K cannot be detected. We then juxtapose our Magellan/IMACS transmission spectrum with existing VLT/FORS2, HST/WFC3, HST/STIS, and Spitzer observations to further constrain the optical-to-infrared atmospheric features of the planet. We find that a steeper scattering slope ({alpha}=8.3{+/-}1.5) is anchored by STIS wavelengths blueward of 400nm and only the original STIS observations show significant potassium signal.
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/301
- Title:
- WASP-147b, 160Bb, 164b, and 165b phot. and RV
- Short Name:
- J/MNRAS/482/301
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four transiting hot Jupiters, WASP-147, WASP-160B, WASP-164, and WASP-165 from the WASP survey. WASP-147b is a near Saturn-mass (Mp=0.28M_J_) object with a radius of 1.11R_J_ orbiting a G4 star with a period (of 4.6d. WASP-160Bb has a mass and radius (Mp=0.28M_J_, Rp=1.09R_J_) (near-identical to WASP-147b, but is less irradiated, orbiting a metal-rich ([Fe/H]*=0.27) K0 star with a period of 3.8d. WASP-160B is part of a near equal-mass visual binary with an on-sky separation of 28.5 arcsec. WASP-164b is a more massive (Mp=2.13M_J_, Rp=1.13R_J_) hot Jupiter, orbiting a G2 star on a close-in (P=1.8d), but tidally stable orbit. WASP-165b is a classical (Mp=0.66M_J_, Rp=1.26R_J_) hot Jupiter in a 3.5d period orbit around a metal-rich ([Fe/H]*=0.33) star. WASP-147b and WASP-160Bb are promising targets for atmospheric characterization through transmission spectroscopy, while WASP-164b presents a good target for emission spectroscopy.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2428
- Title:
- WASP-31b:HST/Spitzer transmission spectral survey
- Short Name:
- J/MNRAS/446/2428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Hubble Space Telescope optical and near-IR transmission spectra of the transiting hot-Jupiter WASP-31b. The spectrum covers 0.3-1.7 {mu}m at a resolution R~70, which we combine with Spitzer photometry to cover the full-optical to IR. The spectrum is dominated by a cloud deck with a flat transmission spectrum which is apparent at wavelengths >0.52{mu}m. The cloud deck is present at high altitudes and low pressures, as it covers the majority of the expected optical Na line and near-IR H_2_O features. While Na I absorption is not clearly identified, the resulting spectrum does show a very strong potassium feature detected at the 4.2{sigma} confidence level. Broadened alkali wings are not detected, indicating pressures below ~10 mbar. The lack of Na and strong K is the first indication of a sub-solar Na/K abundance ratio in a planetary atmosphere (ln[Na/K]=-3.3+/-2.8), which could potentially be explained by Na condensation on the planet's night side, or primordial abundance variations. A strong Rayleigh scattering signature is detected at short wavelengths, with a 4{sigma} significant slope. Two distinct aerosol size populations can explain the spectra, with a smaller sub-micron size grain population reaching high altitudes producing a blue Rayleigh scattering signature on top of a larger, lower lying population responsible for the flat cloud deck at longer wavelengths. We estimate that the atmospheric circulation is sufficiently strong to mix micron size particles upwards to the required 1-10 mbar pressures, necessary to explain the cloud deck. These results further confirm the importance of clouds in hot Jupiters, which can potentially dominate the overall spectra and may alter the abundances of key gaseous species.
- ID:
- ivo://CDS.VizieR/J/A+A/625/A136
- Title:
- WASP-18b HST/WFC3 spectroscopic phase curves
- Short Name:
- J/A+A/625/A136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of a full-orbit, spectroscopic phase curve of the ultra hot Jupiter (UHJ) WASP-18b, obtained with the Wide Field Camera 3 aboard the Hubble Space Telescope. We measured the normalised day-night contrast of the planet as >0.96 in luminosity: the disc-integrated dayside emission from the planet is at 964+/-25ppm, corresponding to 2894+/-30K, and we place an upper limit on the nightside emission of <32ppm or 1430K at the 3{sigma}level. We also find that the peak of the phase curve exhibits a small, but significant oset in brightness of 4.5+/-0.5 degrees eastward. We compare the extracted phase curve and phase-resolved spectra to 3D global circulation models and find that broadly the data can be well reproduced by some of these models. We find from this comparison several constraints on the atmospheric properties of the planet. Firstly we find that we need ecient drag to explain the very inefficient day-night recirculation observed.We demonstrate that this drag could be due to Lorentz-force drag by a magnetic field as weak as 10 gauss. Secondly, we show that a high metallicity is not required to match the large day-night temperature contrast. In fact, the effect of metallicity on the phase curve is different from cooler gas-giant counterparts because of the high-temperature chemistry in the atmosphere of WASP-18b. Additionally, we compared the current UHJ spectroscopic phase curves, WASP-18b and WASP-103b, and show that these two planets provide a consistent picture with remarkable similarities in their measured and inferred properties. However, key differences in these properties, such as their brightness osets and radius anomalies, suggest that UHJ could be used to separate between competing theories for the inflation of gas-giant planets.
3036. WASP-21b light curves
- ID:
- ivo://CDS.VizieR/J/MNRAS/497/5182
- Title:
- WASP-21b light curves
- Short Name:
- J/MNRAS/497/5182
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the optical transmission spectrum of the highly inflated Saturn- mass exoplanet WASP-21b, using three transits obtained with the ACAM instrument on the William Herschel Telescope through the LRG-BEASTS survey (Low Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy). Our transmission spectrum covers a wavelength range of 4635-9000{AA}, achieving an average transit depth precision of 197ppm compared to one atmospheric scale height at 246ppm. We detect NaI absorption in a bin width of 30{AA}, at >4{sigma} confidence, which extends over 100{AA}. We see no evidence of absorption from KI. Atmospheric retrieval analysis of the scattering slope indicates it is too steep for Rayleigh scattering from H_2, but is very similar to that of HD 189733b. The features observed in our transmission spectrum cannot be caused by stellar activity alone, with photometric monitoring of WASP-21 showing it to be an inactive star. We therefore conclude that aerosols in the atmosphere of WASP-21b are giving rise to the steep slope that we observe, and that WASP-21b is an excellent target for infra-red observations to constrain its atmospheric metallicity.
- ID:
- ivo://CDS.VizieR/J/A+A/563/A41
- Title:
- WASP-43 OSIRIS transmission spectroscopy
- Short Name:
- J/A+A/563/A41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the Gran Telescopio Canarias (GTC) instrument OSIRIS to obtain long-slit spectra in the optical range 520-1040nm of the planetary host star WASP-43 and of a reference star during a full primary transit event. We integrated the stellar flux of both stars in different wavelength regions producing several light curves. We measure a mean planet-to-star radius ratio in the white light curve of 0.15988^+0.00133^_-0.00145_. We present a tentative detection in the planet-to-star radius ratio around the NaI doublet ({lambda} 588.9, 589.5nm) when compared to the nearby continuum at the 2.9-sigma level. We find no significant excess of the measured planet-to-star radius ratio around the KI doublet ({lambda} 766.5nm, 769.9nm) when compared to the nearby continuum.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A139
- Title:
- Water lines spectra of 4 protostellar objects
- Short Name:
- J/A+A/587/A139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Herschel/HIFI observations of 14 water lines in a small sample of galactic massive protostellar objects: NGC6334I(N), DR21(OH), IRAS16272-4837, and IRAS05358+3543. Using water as a tracer of the structure and kinematics, we aim to individually study each of these objects, to estimate the amount of water around them, but to also shed light on the high-mass star formation process. We analyze the gas dynamics from the line profiles using Herschel-HIFI observations acquired as part of the WISH key-project of 14 far-IR water lines (water, H_2_^17^O, H_2_^18^O), and several other species. Then through modeling of the observations using the RATRAN radiative transfer code, we estimate outflow, infall, turbulent velocities, molecular abundances, and investigate any correlation with the evolutionary status of each source. The four sources (plus previously studied W43-MM1) have been ordered in terms of evolution based on their SED: NGC64334I(N)-W43-MM1-DR21(OH)-IRAS16272-4837-IRAS05358+3543. The molecular line profiles exhibit a broad component coming from the shocks along the cavity walls associated with the protostars, and an infalling (or expansion for IRAS05358+3543) and passively heated envelope component, with highly supersonic turbulence likely increasing with the distance from the center. Accretion rates between 6.3x10^-5^ and 5.6x10^-4^M_{sun}_/yr are derived from the infall observed in three of our sources. The outer water abundance is estimated to be at the typical value of a few 10^-8^ while the inner abundance varies from 1.7x10^-6^ to 1.4x10^-4^ with respect to H_2_ depending on the source. We confirm that regions of massive star formation are highly turbulent and that the turbulence likely increases in the envelope with the distance to the star. The inner abundances are lower than the expected 10^-4^ perhaps because our observed lines do not probe deep enough into the inner envelope, or because photodissociation through protostellar UV photons is more efficient than expected. We show that the higher the infall/expansion velocity in the protostellar envelope, the higher is the inner abundance, maybe indicating that larger infall/expansion velocities generate shocks that will sputter water from the ice mantles of dust grains in the inner region. High-velocity water must be formed in the gas-phase from shocked material.
3039. Wavelength calibration
- ID:
- ivo://CDS.VizieR/J/A+AS/128/409
- Title:
- Wavelength calibration
- Short Name:
- J/A+AS/128/409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Thorium-Argon lamps are commonly used as wavelength calibration units at moderately high spectral resolutions because of the richness of the thorium spectrum in the visual. The inclusion of blended lines whose position is assumed to coincide with the laboratory wavelength of the main component is shown to result in a calibration precision significantly worse than the intrinsic random noise limit. In order to avoid this degradation of the calibration, we present resolution-dependent Th-Ar wavelengths in the region 277 to >1000nm for use at pixel-scales (pixel-size expressed in wavelength units) between {lambda}/2.5x10+4 and {lambda}/10+5.
- ID:
- ivo://CDS.VizieR/III/130
- Title:
- Wavelength Dependence of Galactic UV Extinction
- Short Name:
- III/130
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A collection of data for 115 extinction curves derived from low-dispersion IUE spectra are presented with normalization to E(B-V)=1. The electronic Atlas of Extinctions contains the list of the stars used, their association membership, and the normalized extinctions for 88 wavelength values between 1260 and 3000 Angstroems.
