We utilized the new high-order 585 actuator Magellan Adaptive Optics system (MagAO) to obtain very high-resolution visible light images of HD 142527 with MagAO's VisAO science camera. In the median ...seeing conditions of the 6.5 m Magellan telescope (0".5-0".7), we find MagAO delivers 24%-19% Strehl at H alpha (0.656 mu m). We detect a faint companion (HD 142527B) embedded in this young transitional disk system at just 86.3 + or - 1.9 mas (~12 AU) from the star. The companion is detected in both H alpha and a continuum filter ( Delta mag = 6.33 + or - 0.20 mag at H alpha and 7.50 + or - 0.25 mag in the continuum filter). This provides confirmation of the tentative companion discovered by Biller and co-workers with sparse aperture masking at the 8 m Very Large Telescope. The H alpha emission from the ~0.25 solar mass companion (EW = 180 A) implies a mass accretion rate of ~5.9 x 10 super(-10) M sub(sun) yr super(-1) and a total accretion luminosity of 1.2% L sub(sun). Assuming a similar accretion rate, we estimate that a 1 Jupiter mass gas giant could have considerably better (50-1000x) planet/star contrasts at H alpha than at the H band (COND models) for a range of optical extinctions (3.4-0 mag). We suggest that ~0.5-5-M sub(jup) extrasolar planets in their gas accretion phase could be much more luminous at H alpha than in the NIR. This is the motivation for our new MagAO GAPplanetS survey for extrasolar planets.
The
Gaia
Multipeak (GMP) technique can be used to identify large numbers of dual or lensed active galactic nucleus (AGN) candidates at subarcsec separation, allowing us to study both multiple ...supermassive black holes (SMBHs) in the same galaxy and rare, compact lensed systems. The observed samples can be used to test the predictions of the models of SMBH merging when (1) the selection function of the GMP technique is known, and (2) each system has been classified as a dual AGN, a lensed AGN, or an AGN/star alignment. Here we show that the GMP selection is very efficient for separations above 0.15″ when the secondary (fainter) object has a magnitude
G
≲ 20.5. We present the spectroscopic classification of five GMP candidates using VLT/ERIS and Keck/OSIRIS and compare them with the classifications obtained from (a) the near-IR colors of seven systems obtained with LBT/LUCI, and (b) the analysis of the total spatially unresolved spectra. We conclude that colors and integrated spectra can already provide reliable classifications of many systems. Finally, we summarize the confirmed dual AGNs at
z
> 0.5 selected by the GMP technique, and compare this sample with other such systems from the literature, concluding that GMP can provide a large number of confirmed dual AGNs at separations below 7 kpc.
Context. The formation of OB-type stars up to (at least) 140 M⊙ can be explained via disk-mediated accretion and in fact growing observational evidence of disk-jet systems is found in high-mass ...star-forming regions. Aims. With the present observations we wish to investigate at sub-arcsecond resolution the jet structure close to the well studied high-mass protostar IRAS 20126+4104, which is known to be surrounded by a Keplerian disk. Methods. Adaptive optics imaging of the 2.2 μm continuum and H2 and Brγ line emission have been performed with the Large Binocular Telescope, attaining an angular resolution of ~90 mas and an astrometric precision of ~100 mas. Results. While our results are consistent with previous K-band images by other authors, the improved (by a factor ~3) resolution allows us to identify a number of previously unseen features, such as bow shocks spread all over the jet structure. Also, we confirm the existence of a bipolar nebulosity within 1′′ from the protostar, prove that the emission from the brightest, SE lobe is mostly due to the H2 line, and resolve its structure. Conclusions. Comparison with other tracers such as masers, thermal molecular line emission, and free-free continuum emission proves that the bipolar nebulosity is indeed tracing the root of the bipolar jet powered by the deeply embedded protostar at the center of the Keplerian disk.
We have performed H and K sub(s) band observations of the planetary system around HR 8799 using the new AO system at the Large Binocular Telescope and the PISCES Camera. The excellent instrument ...performance (Strehl ratios up to 80% in H band) enabled the detection of the innermost planet, HR 8799e, at H band for the first time. The H and K sub(s) magnitudes of HR 8799e are similar to those of planets c and d, with planet e being slightly brighter. Therefore, HR 8799e is likely slightly more massive than c and d. We also explored possible orbital configurations and their orbital stability. We confirm that the orbits of planets b, c and e are consistent with being circular and coplanar; planet d should have either an orbital eccentricity of about 0.1 or be non-coplanar with respect to b and c. Planet e can not be in circular and coplanar orbit in a 4:2:1 mean motion resonances with c and d, while coplanar and circular orbits are allowed for a 5:2 resonance. The analysis of dynamical stability shows that the system is highly unstable or chaotic when planetary masses of about 5 M sub(J) for b and 7 M sub(J) for the other planets are adopted. Significant regions of dynamical stability for timescales of tens of Myr are found when adopting planetary masses of about 3.5, 5, 5, and 5 M sub(J) for HR 8799b, c, d, and e respectively. These masses are below the current estimates based on the stellar age (30 Myr) and theoretical models of substellar objects.
Using the adaptive optics system of the Large Binocular Telescope, we have obtained near-infrared camera PISCES images of the inner shell of the nebula around the luminous blue variable star P Cygni ...in the Fe ii emission line at 1.6435 μm. We have combined the images in order to cover a field of view of about 20 arcsec around P Cygni, thus providing the high-resolution (0.08 arcsec) two-dimensional spatial distribution of the inner shell of the P Cygni nebula in Fe ii. We have identified several nebular emission regions that are characterized by a signal-to-noise ratio > 3. A comparison of our results with those available in the literature shows full consistency with the findings of Smith & Hartigan, which are based on radial velocity measurements, and relatively good agreement with the extension of emission nebula in N ii λ6584 found by Barlow et al. We have clearly also detected extended emission inside the radial distance R = 7.8 arcsec and outside R = 9.7 arcsec, which are the nebular boundaries proposed by Smith & Hartigan. New complementary spectroscopic observations are planned in order to measure radial velocities and to derive the three-dimensional distribution of the P Cygni nebula.
The new 8.4 m LBT adaptive secondary AO system, with its novel pyramid wavefront sensor, was used to produce very high Strehl (> ~75% at 2.16 mu m) near-infrared narrowband (Br gamma : 2.16 mu m and ...FeII: 1.64 mu m) images of 47 young (~1 Myr) Orion Trapezium theta super(1) Ori cluster members. The inner ~41 x 53" of the cluster was imaged at spatial resolutions of ~0".050 (at 1.64 mu m). A combination of high spatial resolution and high S/N yielded relative binary positions to ~0.5 mas accuracies. Including previous speckle data, we analyze a 15 year baseline of high-resolution observations of this cluster. We are now sensitive to relative proper motions of just ~0.3 mas yr super(-1) (0.6 km s super(-1) at 450 pc); this is a ~7 x improvement in orbital velocity accuracy compared to previous efforts. We now detect clear orbital motions in the theta super(1) Ori B sub(2)B sub(3) system of 4.9 + or - 0.3 km s super(-1) and 7.2 + or - 0.8 km s super(-1) in the theta super(1) Ori A sub(1)A sub(2) system (with correlations of P.A. versus time at >99% confidence). All five members of the theta super(1) Ori B system appear likely a gravitationally bound "mini-cluster." The very lowest mass member of the theta super(1) Ori B system (B sub(4); mass ~0.2 M sub(middot in circle)) has, for the first time, a clearly detected motion (at 4.3 + or - 2.0 km s super(-1); correlation = 99.7%) w.r.t. B sub(1). However, B sub(4) is most likely in a long-term unstable (non-hierarchical) orbit and may "soon" be ejected from this "mini-cluster." This "ejection" process could play a major role in the formation of low-mass stars and brown dwarfs.
We utilize the new Magellan adaptive optics system (MagAO) to image the binary proplyd LV 1 in the Orion Trapezium at H alpha . This is among the first AO results in visible wavelengths. The H alpha ...image clearly shows the ionization fronts, the interproplyd shell, and the cometary tails. Our astrometric measurements find no significant relative motion between components over ~18 yr, implying that LV 1 is a low-mass system. We also analyze Large Binocular Telescope AO observations, and find a point source which may be the embedded protostar's photosphere in the continuum. Converting the H magnitudes to mass, we show that the LV 1 binary may consist of one very-low-mass star with a likely brown dwarf secondary, or even plausibly a double brown dwarf. Finally, the magnetopause of the minor proplyd is estimated to have a radius of 110 AU, consistent with the location of the bow shock seen in H alpha .
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