Context. The observation of planets in their formation stage is a crucial but very challenging step in understanding when, how, and where planets form. PDS 70 is a young pre-main sequence star ...surrounded by a transition disk, in the gap of which a planetary-mass companion has recently been discovered. This discovery represents the first robust direct detection of such a young planet, possibly still at the stage of formation. Aims. We aim to characterize the orbital and atmospheric properties of PDS 70 b, which was first identified on May 2015 in the course of the SHINE survey with SPHERE, the extreme adaptive-optics instrument at the VLT. Methods. We obtained new deep SPHERE/IRDIS imaging and SPHERE/IFS spectroscopic observations of PDS 70 b. The astrometric baseline now covers 6 yr, which allowed us to perform an orbital analysis. For the first time, we present spectrophotometry of the young planet which covers almost the entire near-infrared range (0.96–3.8 μm). We use different atmospheric models covering a large parameter space in temperature, log g, chemical composition, and cloud properties to characterize the properties of the atmosphere of PDS 70 b. Results. PDS 70 b is most likely orbiting the star on a circular and disk coplanar orbit at ~22 au inside the gap of the disk. We find a range of models that can describe the spectrophotometric data reasonably well in the temperature range 1000–1600 K and log g no larger than 3.5 dex. The planet radius covers a relatively large range between 1.4 and 3.7 RJ with the larger radii being higher than expected from planet evolution models for the age of the planet of 5.4 Myr. Conclusions. This study provides a comprehensive data set on the orbital motion of PDS 70 b, indicating a circular orbit and a motion coplanar with the disk. The first detailed spectral energy distribution of PDS 70 b indicates a temperature typical of young giant planets. The detailed atmospheric analysis indicates that a circumplanetary disk may contribute to the total planetflux.
Aims. We investigate the fueling and the feedback of nuclear activity in the nearby (D = 14 Mpc) Seyfert 2 barred galaxy NGC 1068 by studying the distribution and kinematics of molecular gas in the ...torus and its connections to the host galaxy disk. Methods. We used the Atacama Large Millimeter Array (ALMA ) to image the emission of a set of molecular gas tracers in the circumnuclear disk (CND) and the torus of the galaxy using the CO(2–1), CO(3–2), and HCO+(4–3) lines and their underlying continuum emission with high spatial resolutions (0.03″ − 0.09″ ≃ 2 − 6 pc). These transitions, which span a wide range of physical conditions of molecular gas (n(H2)⊂103 − 107 cm−3), are instrumental in revealing the density radial stratification and the complex kinematics of the gas in the torus and its surroundings. Results. The ALMA images resolve the CND as an asymmetric ringed disk of D ≃ 400 pc in size and ≃1.4 × 108 M⊙ in mass. The CND shows a marked deficit of molecular gas in its central ≃130 pc region. The inner edge of the ring is associated with the presence of edge-brightened arcs of NIR polarized emission, which are identified with the current working surface of the ionized wind of the active galactic nucleus (AGN). ALMA proves the existence of an elongated molecular disk/torus in NGC 1068 of Mtorusgas ≃ 3 × 105 M⊙ M torus gas ≃ 3 × 10 5 M ⊙ $ M_{\mathrm{torus}}^{\mathrm{gas}}\simeq3\times10^{5}\,M_{{\odot}} $ , which extends over a large range of spatial scales D ≃ 10 − 30 pc around the central engine. The new observations evidence the density radial stratification of the torus: the HCO+(4–3) torus, with a full size DHCO+(4 − 3) = 11 ± 0.6 pc, is a factor of between two and three smaller than its CO(2–1) and CO(3–2) counterparts, which have full sizes of DCO(3 − 2) = 26 ± 0.6 pc and DCO(2 − 1) = 28 ± 0.6 pc, respectively. This result brings into light the many faces of the molecular torus. The torus is connected to the CND through a network of molecular gas streamers detected inside the CND ring. The kinematics of molecular gas show strong departures from circular motions in the torus, the gas streamers, and the CND ring. These velocity field distortions are interconnected and are part of a 3D outflow that reflects the effects of AGN feedback on the kinematics of molecular gas across a wide range of spatial scales around the central engine. In particular, we estimate through modeling that a significant fraction of the gas inside the torus ( ≃ 0.4 − 0.6 × Mtorusgas ≃ 0.4 − 0.6 × M torus gas $ {\simeq}0.4{-}0.6 \times M_{\mathrm{torus}}^{\mathrm{gas}} $ ) and a comparable amount of mass along the gas streamers are outflowing. However, the bulk of the mass, momentum, and energy of the molecular outflow of NGC 1068 is contained at larger radii in the CND region, where the AGN wind and the radio jet are currently pushing the gas assembled at the Inner Lindblad Resonance (ILR) ring of the nuclear stellar bar. Conclusions. In our favored scenario a wide-angle AGN wind launched from the accretion disk of NGC1068 is currently impacting a sizable fraction of the gas inside the torus. However, a large gas reservoir (≃1.2 − 1.8 × 105 M⊙), which lies close to the equatorial plane of the torus, remains unaffected by the feedback of the AGN wind and can therefore continue fueling the AGN for at least ≃1 − 4 Myr. Nevertheless, AGN fueling currently seems thwarted on intermediate scales (15 pc ≤r ≤ 50 pc).
We present new near-infrared VLTI/GRAVITY interferometric spectra that spatially resolve the broad Br
γ
emission line in the nucleus of the active galaxy IRAS 09149−6206. We use these data to measure ...the size of the broad line region (BLR) and estimate the mass of the central black hole. Using an improved phase calibration method that reduces the differential phase uncertainty to 0.05° per baseline across the spectrum, we detect a differential phase signal that reaches a maximum of ∼0.5° between the line and continuum. This represents an offset of ∼120
μ
as (0.14 pc) between the BLR and the centroid of the hot dust distribution traced by the 2.3
μ
m continuum. The offset is well within the dust sublimation region, which matches the measured ∼0.6 mas (0.7 pc) diameter of the continuum. A clear velocity gradient, almost perpendicular to the offset, is traced by the reconstructed photocentres of the spectral channels of the Br
γ
line. We infer the radius of the BLR to be ∼65
μ
as (0.075 pc), which is consistent with the radius–luminosity relation of nearby active galactic nuclei derived based on the time lag of the H
β
line from reverberation mapping campaigns. Our dynamical modelling indicates the black hole mass is ∼1 × 10
8
M
⊙
, which is a little below, but consistent with, the standard
M
BH
–
σ
*
relation.
We present near-infrared interferometric data on the Seyfert 2 galaxy NGC 1068, obtained with the GRAVITY instrument on the European Southern Observatory Very Large Telescope Interferometer. The ...extensive baseline coverage from 5 to 60
M
λ
allowed us to reconstruct a continuum image of the nucleus with an unrivaled 0.2 pc resolution in the
K
-band. We find a thin ring-like structure of emission with a radius
r
= 0.24 ± 0.03 pc, inclination
i
= 70 ± 5°, position angle PA = −50 ± 4°, and
h
/
r
< 0.14, which we associate with the dust sublimation region. The observed morphology is inconsistent with the expected signatures of a geometrically and optically thick torus. Instead, the infrared emission shows a striking resemblance to the 22 GHz maser disc, which suggests they share a common region of origin. The near-infrared spectral energy distribution indicates a bolometric luminosity of (0.4–4.7) × 10
45
erg s
−1
, behind a large
A
K
≈ 5.5 (
A
V
≈ 90) screen of extinction that also appears to contribute significantly to obscuring the broad line region.
Context. PDS 70 is a young (5.4 Myr), nearby (~113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect ...a planetary mass companion, PDS 70 b, within the disk cavity. Moreover, observations in Hα with MagAO and MUSE revealed emission associated to PDS 70 b and to another new companion candidate, PDS 70 c, at a larger separation from the star. PDS 70 is the only multiple planetary system at its formation stage detected so far through direct imaging. Aims. Our aim is to confirm the discovery of the second planet PDS 70 c using SPHERE at VLT, to further characterize its physical properties, and search for additional point sources in this young planetary system. Methods. We re-analyzed archival SPHERE NIR observations and obtained new data in Y, J, H and K spectral bands for a total of four different epochs. The data were reduced using the data reduction and handling pipeline and the SPHERE data center. We then applied custom routines (e.g., ANDROMEDA and PACO) to subtract the starlight. Results. We re-detect both PDS 70 b and c and confirm that PDS 70 c is gravitationally bound to the star. We estimate this second planet to be less massive than 5 MJup and with a Teff around 900 K. Also, it has a low gravity with logg between 3.0 and 3.5 dex. In addition, a third object has been identified at short separation (~0.12′′) from the star and gravitationally bound to the star. Its spectrum is however very blue, meaning that we are probably seeing stellar light reflected by dust and our analysis seems to demonstrate that it is a feature of the inner disk. We cannot however completely exclude the possibility that it is a planetary mass object enshrouded by a dust envelope. In this latter case, its mass should be of the order of a few tens of M⊕. Moreover, we propose a possible structure for the planetary system based on our data, and find that this structure cannot be stable on a long timescale.
We use VLTI/GRAVITY near-infrared interferometry measurements of eight bright type 1 AGN to study the size and structure of hot dust that is heated by the central engine. We partially resolve each ...source, and report Gaussian full width at half-maximum sizes in the range 0.3−0.8 mas. In all but one object, we find no evidence for significant elongation or asymmetry (closure phases ≲1°). The narrow range of measured angular sizes is expected given the similar optical flux of our targets, and implies an increasing effective physical radius with bolometric luminosity, as found from previous reverberation and interferometry measurements. The measured sizes for Seyfert galaxies are systematically larger than for the two quasars in our sample when measured relative to the previously reported
R
∼
L
1/2
relationship, which is explained by emission at the sublimation radius. This could be evidence of an evolving near-infrared emission region structure as a function of central luminosity.
Here, we show that the approximately 10-million-year-old β Pictoris system hosts a massive giant planet, β Pictoris b, located 8 to 15 astronomical units from the star. This result confirms that gas ...giant planets form rapidly within disks and validates the use of disk structures as fingerprints of embedded planets. Among the few planets already imaged, β Pictoris b is the closest to its parent star. Its short period could allow for recording of the full orbit within 17 years.
The broadening of atomic emission lines by high-velocity motion of gas near accreting supermassive black holes is an observational hallmark of quasars
. Observations of broad emission lines could ...potentially constrain the mechanism for transporting gas inwards through accretion disks or outwards through winds
. The size of regions for which broad emission lines are observed (broad-line regions) has been estimated by measuring the delay in light travel time between the variable brightness of the accretion disk continuum and the emission lines
-a method known as reverberation mapping. In some models the emission lines arise from a continuous outflow
, whereas in others they arise from orbiting gas clouds
. Directly imaging such regions has not hitherto been possible because of their small angular size (less than 10
arcseconds
). Here we report a spatial offset (with a spatial resolution of 10
arcseconds, or about 0.03 parsecs for a distance of 550 million parsecs) between the red and blue photo-centres of the broad Paschen-α line of the quasar 3C 273 perpendicular to the direction of its radio jet. This spatial offset corresponds to a gradient in the velocity of the gas and thus implies that the gas is orbiting the central supermassive black hole. The data are well fitted by a broad-line-region model of a thick disk of gravitationally bound material orbiting a black hole of 3 × 10
solar masses. We infer a disk radius of 150 light days; a radius of 100-400 light days was found previously using reverberation mapping
. The rotation axis of the disk aligns in inclination and position angle with the radio jet. Our results support the methods that are often used to estimate the masses of accreting supermassive black holes and to study their evolution over cosmic time.
Aims. The SHINE program is a high-contrast near-infrared survey of 600 young, nearby stars aimed at searching for and characterizing new planetary systems using VLT/SPHERE’s unprecedented ...high-contrast and high-angular-resolution imaging capabilities. It is also intended to place statistical constraints on the rate, mass and orbital distributions of the giant planet population at large orbits as a function of the stellar host mass and age to test planet-formation theories. Methods. We used the IRDIS dual-band imager and the IFS integral field spectrograph of SPHERE to acquire high-contrast coronagraphic differential near-infrared images and spectra of the young A2 star HIP 65426. It is a member of the ~17 Myr old Lower Centaurus-Crux association. Results. At a separation of 830 mas (92 au projected) from the star, we detect a faint red companion. Multi-epoch observations confirm that it shares common proper motion with HIP 65426. Spectro-photometric measurements extracted with IFS and IRDIS between 0.95 and 2.2 μm indicate a warm, dusty atmosphere characteristic of young low-surface-gravity L5-L7 dwarfs. Hot-start evolutionary models predict a luminosity consistent with a 6–12 MJup, Teff = 1300–1600 K and R = 1.5 ± 0.1 RJup giant planet. Finally, the comparison with Exo-REM and PHOENIX BT-Settl synthetic atmosphere models gives consistent effective temperatures but with slightly higher surface gravity solutions of log (g) = 4.0–5.0 with smaller radii (1.0–1.3 RJup). Conclusions. Given its physical and spectral properties, HIP 65426 b occupies a rather unique placement in terms of age, mass, and spectral-type among the currently known imaged planets. It represents a particularly interesting case to study the presence of clouds as a function of particle size, composition, and location in the atmosphere, to search for signatures of non-equilibrium chemistry, and finally to test the theory of planet formation and evolution.
The angular size of the broad line region (BLR) of the nearby active galactic nucleus NGC 3783 has been spatially resolved by recent observations with VLTI/GRAVITY. A reverberation mapping (RM) ...campaign has also recently obtained high quality light curves and measured the linear size of the BLR in a way that is complementary to the GRAVITY measurement. The size and kinematics of the BLR can be better constrained by a joint analysis that combines both GRAVITY and RM data. This, in turn, allows us to obtain the mass of the supermassive black hole in NGC 3783 with an accuracy that is about a factor of two better than that inferred from GRAVITY data alone. We derive
M
BH
= 2.54
−0.72
+0.90
× 10
7
M
⊙
. Finally, and perhaps most notably, we are able to measure a geometric distance to NGC 3783 of 39.9
−11.9
+14.5
Mpc. We are able to test the robustness of the BLR-based geometric distance with measurements based on the Tully–Fisher relation and other indirect methods. We find the geometric distance is consistent with other methods within their scatter. We explore the potential of BLR-based geometric distances to directly constrain the Hubble constant,
H
0
, and identify differential phase uncertainties as the current dominant limitation to the
H
0
measurement precision for individual sources.
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