We report an orbital characterization of GJ1108Aab that is a low-mass binary system in the pre-main-sequence phase. Via the combination of astrometry using adaptive optics and radial velocity measurements, an eccentric orbital solution of e = 0.63 is obtained, which might be induced by the Kozai–Lidov mechanism with a widely separated GJ1108B system. Combined with several observed properties, we confirm that the system is indeed young. Columba is the most probable moving group, to which the GJ1108A system belongs, although its membership to the group has not been established. If the age of Columba is assumed for GJ1108A, the dynamical masses of both GJ1108Aa and GJ1108Ab (Mdynamical,GJ1108Aa = 0.72 ± 0.04 M⊙ and Mdynamical,GJ1108Ab = 0.30 ± 0.03 M⊙) are more massive than what an evolutionary model predicts based on the age and luminosities. We consider that the discrepancy in mass comparison can be attributed to an age uncertainty; the system is likely older than stars in Columba, and effects that are not implemented in classical models such as accretion history and magnetic activity are not preferred to explain the mass discrepancy. We also discuss the performance of the evolutionary model by compiling similar low-mass objects in the evolutionary state based on the literature. Consequently, it is suggested that the current model on average reproduces the mass of resolved low-mass binaries without any significant offsets.

Small, rocky planets in the habitable zones of their host stars are the most promising places to search for alien life. With the discovery of thousands of extrasolar planets, we now know that small planets like Earth are also some of the most abundant. Detecting these planets around Sun-like stars is very challenging due to the low probability of transits (<1%), the infrequency of transits even if they do occur (⇠1/year), and the tiny radial velocity (RV) signal (⇠10 cm s ). Late-M dwarf stars (LMDs; spectral type later than M4) are much more promising targets for a Doppler search. Low stellar masses (⇠0.1–0.2 M ) and short planetary orbital periods (⇠3–30 days) result in much larger RV signals (⇠1–5 m s ) for ⇠1–3 Earth mass planets (hereafter Earth-mass planets) in the habitable zone (HZ). However, LMDs are very faint at optical wavelengths, and there have as yet been no systematic planet searches around nearby LMDs. We propose an extensive, precise near-infrared (NIR) RV survey focused on LMDs using the newly-commissioned InfraRed Doppler (IRD) instrument in the framework of the Subaru Strategic Program (SSP). IRD is ideally suited to measure precise RVs of LMDs because: (1) the stars have a flux peak in NIR, (2) there are many absorption lines in their NIR spectra, and (3) those lines are less a↵ected by stellar activity than optical lines. IRD is an echelle spectrometer that covers the NIR wavelengths from 0.97 to 1.75 μm with a high spectral resolution (70,000); it uses a laser frequency comb as an extremely precise wavelength calibrator. IRD’s high instrumental stability and its use of a laser frequency comb allow us to measure the RVs of LMDs with a precision of 2 m s 1 or better. The goals of our survey are: (1) to discover Earth-mass planets in the HZ around these low-mass stars, and (2) to uncover the distribution of planetary systems containing Earth-mass planets and more massive planets. To achieve these goals, we will carry out an extensive high-precision RV survey of 60 carefully selected low-mass stars using 175 observing nights of the Subaru telescope over 5 years. Our initial target samples are collected from the literature and from the results of our pre-selection observations with optical spectroscopy of H↵ lines. This will screen out active stars, leaving us with the targets best suited for very high precision RV measurements. According to a simulation of the RV observations based on both theoretical and empirical planet populations, our proposed observations can discover Earth-mass planets in close-in orbits with periods less than a few tens of days and super-Earths (⇠5 Earth-masses) in orbits with periods less than a few hundred days. So far, only two Earth-“mass” planets in HZ have been reported with Draft version May 20, 2018 Typeset using LATEX default style in AASTeX62 Search for Planets like Earth around Late-M Dwarfs: Precise Radial Velocity Survey with IRD PI: Bun 0 ei Sato (Tokyo Institute of Technology) Co-PI: Nagayoshi Ohashi (NAOJ, Subaru) E. Akiyama, W. Aoki, C. Beichman, T. Brandt, G. Cataldi, C. Clergeon, T. Currie, R. Dong, Y. Fujii, H. Fujiwar , A. Fukui, H. Genda, T. Groff, O. Guyon, D. Hall, H. Harakawa, J. Hashim to, Y. Hayano, M. Hayashi, K. G. He lminiak, T. Henning, T. Hirano, K. Hodapp, Y. Hori, Y. Ikeda, S. Inutsuka, H. T. Ishikawa, M. Ishizuka, H. Izumiura, S. Jacobson, M. Janson, N. Jovanovic , E. Kambe, H. Kawahara, T. Kodama, Y. Koizumi, E. Kokubo, M. Konishi, T. Kotani, T. Kudo, T. Kurokawa, N. Kusakabe, M. Kuzuhara, J. Kwon, C. Lee, J. Livingston, M. Machida, T. Matsuo, D. Mawet, M. McElwain, V. Meadows, E. Mieda, T. Mizuki, J. Morino, T. Nagata, T. Nakagawa, T. Nakajima, N. Narita, J. Nishikawa, S. Nishiyama, H. Nomura, M. Ogihara, D. Oh, M. Omiya, S. Oshino, T. Pyo, E. Serabyn, M. Sitko, H. Suto, R. Suzuki, Y. Takagi, H. Takami, T. Takarada, . Takato, M. Tamura, Y. Tanaka, H. Terada, R. A. Torres, E. L. Turner, A. Ueda, T Usud , T. Uyama, S. Vievard, J. Wang, J. Wisniewski, and Y. Yang 1. Hokkaido University; 2. NAOJ; 3. JPL/Caltech; 4. UC Santa Barbara; 5. Subaru Telescope; 6. University of Victoria; 7. ELSI; 8. Tokyo Institute of Technology; 9. NASA Goddard; 10. University of Arizona; 11. Astrobiology Center, NINS; 12. Nicolaus Copernicus Astronomical Center; 13. MPIA; 14. Photocoding; 15. University of Tokyo; 16. ISAS/JAXA; 17. Stockholm University; 18. Miyagi University of Education; 19. Space Science Institute; 20. Kyoto University; 21. SOKENDAI; 22. Princeton University; 23. Caltech; 24. Nagoya University; 25. National Meteorological Satellite Center; 26. University of Oklahoma; 27. Osaka University; 28. Kyushu University; 29. University of Washington; 30. TUAT; 31. University of Hawaii, IfA ABSTRACT Small, rocky planets in the habitable zones of their host stars are the most promising places to search for alien life. With the discovery of thousands of extrasolar planets, we now know that small planets like Earth are also some of the most abundant. Detecting these planets around Sun-like stars is very challenging due to the low probability of transits (<1%), the infrequency of transits even if they do occur (⇠1/year), and the tiny radial velocity (RV) signal (⇠10 cm s ). Late-M dwarf stars (LMDs; spectral type later than M4) are much more promising targets for a Doppler search. Low stellar masses (⇠0.1–0.2 M ) and short planetary orbital periods (⇠3–30 days) result in much larger RV signals (⇠1–5 m s ) for ⇠1–3 Earth mass planets (hereafter Earth-mass planets) in the habitable zone (HZ). However, LMDs are very faint at optical wavelengths, and there have as yet been no systematic planet searches around nearby LMDs. We propose an extensive, precise near-infrared (NIR) RV survey focused on LMDs using the newly-commissioned InfraRed Doppler (IRD) instrument in the framework of the Sub ru Strategic Program (SSP). IRD is ideally suited to measure precise RVs of LMDs because: (1) the stars have a flux peak in NIR, (2) there are many absorption lines in their NIR spectra, and (3) those lines are less a↵ected by stellar activity than optical lines. IRD is an echelle spectrometer that covers the NIR wavelengths from 0.97 to 1.75 μm with a high spectral resolution (70,000); it uses a laser frequency comb as an extremely precise wavelength calibrator. IRD’s high instrumental stability and its use of a laser frequency comb allow us to measure the RVs of LMDs with a precision of 2 m s 1 or better. The goals of our survey are: (1) to discover Earth-mass planets in the HZ around these low-mass stars, and (2) to uncover the distribution of planetary systems containing Earth-mass planets and more massive planets. To achieve these goals, we will carry out an extensive high-precision RV survey of 60 carefully selected low-mass stars using 175 observing ights of the Subaru telesc pe ov r 5 years. Our initial target samples are collected from the literature and from the results of our pre-selection observations with optical spectroscopy of H↵ lines. This will screen out active stars, leaving us with the targets best suited for very high precision RV measurements. According to a simulation of the RV observations based on both theoretical and empirical planet populations, our proposed observations can discover Earth-mass planets in close-in orbits wi h periods less than a few tens of days and super-Earths (⇠5 Earth-mas es) in orbits with periods less than a few hundred days. So far, only two Earth-“mass” planets in HZ have been reported withSmall, rocky planets in the habitable zones of their host stars are the most promising places to search for alien life. With the discovery of thousands of extrasolar planets, we now know that small planets like Earth are also some of the most abundant. Detecting these planets around Sun-like stars is very challenging due to the low probability of transits (<1%), the infrequency of transits even if they do occur (⇠1/year), and the tiny radial velocity (RV) signal (⇠10 cm s ). Late-M dwarf stars (LMDs; spectral type later than M4) are much more promising targets for a Doppler search. Low stellar masses (⇠0.1–0.2 M ) and short planetary orbital periods (⇠3–30 days) result in much larger RV signals (⇠1–5 m s ) for ⇠1–3 Earth mass planets (hereafter Earth-mass planets) in the habitable zone (HZ). However, LMDs are very faint at optical wavelengths, and there have as yet been no systematic planet searches around nearby LMDs. We propose an extensive, precise near-infrared (NIR) RV survey focused on LMDs using the newly-commissioned InfraRed Doppler (IRD) instrument in the framework of the Sub ru Strategic Program (SSP). IRD is ideally suited to measure precise RVs of LMDs because: (1) the stars have a flux peak in NIR, (2) there are many absorption lines in their NIR spectra, and (3) those lines are less a↵ected by stellar activity than optical lines. IRD is an echelle spectrometer that covers the NIR wavelengths from 0.97 to 1.75 μm with a high spectral resolution (70,000); it uses a laser frequency comb as an extremely precise wavelength calibrator. IRD’s high instrumental stability and its use of a laser frequency comb allow us to measure the RVs of LMDs with a precision of 2 m s 1 or better. The goals of our survey are: (1) to discover Earth-mass planets in the HZ around these low-mass stars, and (2) to uncover the distribution of planetary systems containing Earth-mass planets and more massive planets. To achieve these goals, we will carry out an extensive high-precision RV survey of 60 carefully selected low-mass stars using 175 observing ights of the Subaru telesc pe ov r 5 years. Our initial target samples are collected from the literature and from the results of our pre-selection observations with optical spectroscopy of H↵ lines. This will screen out active stars, leaving us with the targets best suited for very high precision RV measurements. According to a simulation of the RV observations based on both theoretical and empirical p

We present high signal-to-noise ratio, precise $YJH$ photometry and $Y$ band (\gpiwave~$\mu$m) spectroscopy of HD 1160 B, a young substellar companion discovered from the Gemini NICI Planet Finding Campaign, using the Subaru Coronagraphic Extreme Adaptive Optics instrument and the Gemini Planet Imager. HD 1160 B has typical mid-M dwarf-like infrared colors and a spectral type of M5.5$^{+1.0}_{-0.5}$, where the blue edge of our $Y$ band spectrum rules out earlier spectral types. Atmospheric modeling suggests HD 1160 B having an effective temperature of 3000--3100 $K$, a surface gravity of log $g$ = 4--4.5, a radius of~\bestfitradius~$R_{\rm J}$, and a luminosity of log $L$/$L_{\odot} = -2.76 \pm 0.05$. Neither the primary's Hertzspring-Russell diagram position nor atmospheric modeling of HD 1160 B show evidence for a sub-solar metallicity. The interpretation of the HD 1160 B depends on which stellar system components are used to estimate an age. Considering HD 1160 A, B and C jointly, we derive an age of 80--125 Myr, implying that HD 1160 B straddles the hydrogen-burning limit (70--90 $M_{\rm J}$). If we consider HD 1160 A alone, younger ages (20--125 Myr) and a brown dwarf-like mass (35--90 $M_{\rm J}$) are possible. Interferometric measurements of the primary, a precise GAIA parallax, and moderate resolution spectroscopy can better constrain the system's age and how HD 1160 B fits within the context of (sub)stellar evolution.

epsilon Eridani is one of the nearest solar-type stars. Its proximity and relatively young age allow high-contrast imaging observations to achieve sensitivities to planets at narrow separations down to an inner radius of similar to 5 AU. Previous observational studies of the system report a dust disk with asymmetric morphology as well as a giant planet with large orbital eccentricity, which may require another massive companion to induce the peculiar morphology and to enhance the large orbital eccentricity. In this paper, we report results from deep high-contrast imaging observations to detect the previously reported planet and search for other unseen less massive companions with Subaru/HiCIAO, Gemini-South/NICI, and VLT/NACO. No positive detection was made, but high-contrast measurements with the CH4S narrow-band filter of HiCIAO achieved sensitivities at 14.7 mag differential magnitude level, at an angular separation of 1.0 ''. In terms of planetary mass, as determined by cooling evolutionary models, the highest sensitivities were achieved by the Lp broad-band filter of NACO, resulting in sensitivities corresponding to 1.8, 2.8, and 4.5 M-jup at the projected separation of 3 AU, if 200, 400, and 800 Myr is assumed for the age of the system, respectively. We also discuss origins of the dust disk from the detection sensitivity in the planetary mass and find that a less massive eccentric planet is preferred for disk stirring, which is consistent with the orbital parameters of epsilon Eri b claimed from the previous long-term radial velocity monitoring.

We present high-contrast angular differential imaging (ADI) observations of the debris disk around HD32297 in H-band, as well as the first polarimetric images for this system in polarized differential imaging (PDI) mode with Subaru/HICIAO. In ADI, we detect the nearly edge-on disk at > 5 sigma levels from similar to 0.45 '' to similar to 1.7 '' (50-192AU) from the star and recover the spine deviation from the midplane already found in previous works. We also find for the first time imaging and surface brightness (SB) indications for the presence of a gapped structure on both sides of the disk at distances of similar to 0.75 '' (NE side) and similar to 0.65 '' (SW side). Global forward-modelling work delivers a best-fit model disk and well-fitting parameter intervals that essentially match previous results, with high-forward scattering grains and a ring located at 110AU. However, this single ring model cannot account for the gapped structure seen in our SB profiles. We create simple double ring models and achieve a satisfactory fit with two rings located at 60 and 95AU, respectively, low-forward scattering grains and very sharp inner slopes. In polarized light we retrieve the disk extending from similar to 0.25-1.6 '', although the central region is quite noisy and high S/N are only found in the range similar to 0.75-1.2 ''. The disk is polarized in the azimuthal direction, as expected, and the departure from the midplane is also clearly observed. Evidence for a gapped scenario is not found in the PDI data. We obtain a linear polarization degree of the grains that increases from similar to 10% at 0.55 '' to similar to 25% at 1.6 ''. The maximum is found at scattering angles of similar to 90 degrees, either from the main components of the disk or from dust grains blown out to larger radii.

We report the direct imaging detection of a low-mass companion to a young, moderately active star V450 And, that was previously identified with the radial velocity (RV) method. The companion was found in high-contrast images obtained with the Subaru Telescope equipped with the HiCIAO camera and AO188 adaptive optics system. From the public ELODIE and SOPHIE archives we extracted available high-resolution spectra and RV measurements, along with RVs from the Lick planet search program. We combined our multi-epoch astrometry with these archival, partially unpublished RVs, and found that the companion is a low-mass star, not a brown dwarf, as previously suggested. We found the best-fitting dynamical masses to be and . We also performed spectral analysis of the SOPHIE spectra with the iSpec code. Hipparcos time-series photometry shows a periodicity of P = 5.743 day, which is also seen in the SOPHIE spectra as an RV modulation of the star A. We interpret it as being caused by spots on the stellar surface, and the star to be rotating with the given period. From the rotation and level of activity, we found that the system is Myr old, consistent with an isochrone analysis ( Myr). This work may serve as a test case for future studies of low-mass stars, brown dwarfs, and exoplanets by combination of RV and direct imaging data.

ϵ Eridani is one of the nearest solar-type stars. Its proximity and relatively young age allow high-contrast imaging observations to achieve sensitivities to planets at narrow separations down to an inner radius of ~5 AU. Previous observational studies of the system report a dust disk with asymmetric morphology as well as a giant planet with large orbital eccentricity, which may require another massive companion to induce the peculiar morphology and to enhance the large orbital eccentricity. In this paper, we report results from deep high-contrastimaging observations to detect the previously reported planet and search for other unseen less massive companions with Subaru/HiCIAO, Gemini-South/NICI, and VLT/NACO. No positive detection was made, but high-contrast measurements with the CH4S narrow-band filter of HiCIAO achieved sensitivities at 14.7 mag differential magnitude level, at an angular separation of 1.0″. In terms of planetary mass, as determined by cooling evolutionary models, the highest sensitivities were achieved by the Lp broad-band filter of NACO, resulting in sensitivities corresponding to 1.8, 2.8, and 4.5 Mjup at the projected separation of 3 AU, if 200, 400, and 800 Myr is assumed for the age of the system, respectively. We also discuss origins of the dust disk from the detection sensitivity in the planetary mass and find that a less massive eccentric planet is preferred for disk stirring, which is consistent with the orbital parameters of ϵ Eri b claimed from the previous long-term radial velocity monitoring.

The formation scenario of a gapped disk, i.e., transitional disk, and its asymmetry is still under debate. Proposed scenarios such as disk-planet interaction, photoevaporation, grain growth, anticyclonic vortex, eccentricity, and their combinations would result in different radial distributions of the gas and the small (sub-$\mu$m size) and large (millimeter size) dust grains as well as asymmetric structures in a disk. Optical/near-infrared (NIR) imaging observations and (sub-)millimeter interferometry can trace small and large dust grains, respectively; therefore multi-wavelength observations could help elucidate the origin of complicated structures of a disk. Here we report SMA observations of the dust continuum at 1.3~mm and $^{12}$CO~$J=2\rightarrow1$ line emission of the pre-transitional protoplanetary disk around the solar-mass star PDS~70. PDS~70, a weak-lined T Tauri star, exhibits a gap in the scattered light from its disk with a radius of $\sim$65~AU at NIR wavelengths. However, we found a larger gap in the disk with a radius of $\sim$80~AU at 1.3~mm. Emission from all three disk components (the gas and the small and large dust grains) in images exhibits a deficit in brightness in the central region of the disk, in particular, the dust-disk in small and large dust grains has asymmetric brightness. The contrast ratio of the flux density in the dust continuum between the peak position to the opposite side of the disk reaches 1.4. We suggest the asymmetries and different gap-radii of the disk around PDS~70 are potentially formed by several (unseen) accreting planets inducing dust filtration.

We present a new Subaru/HiCIAO high-contrast H-band polarized intensity (PI) image of a nearby transitional disk associated with TW Hydrae. The scattered light from the disk was detected from 0.2" to 1.5" (11 - 81 AU) and the PI image shows a clear axisymmetric depression in polarized intensity at ~ 0.4" (~ 20 AU) from the central star, similar to the ~ 80 AU gap previously reported from HST images. Azimuthal polarized intensity profile also shows the disk beyond 0.2" is almost axisymmetric. We discuss two possible scenarios explaining the origin of the polarized intensity depression: 1) a gap structure may exist at ~ 20 AU from the central star because of shallow slope seen in the polarized intensity profile, and 2) grain growth may be occurring in the inner region of the disk. Multi-band observations at NIR and millimeter/sub-millimeter wavelengths play a complementary role in investigating dust opacity and may help reveal the origin of the gap more precisely.

Spatially-resolved imaging of Herbig stars and related objects began with HST, but intensified with commissioning of high-contrast imagers on 8-m class telescopes. The bulk of the data taken from the ground have been polarized intensity imagery at H-band, with the majority of the sources observed as part of the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) survey. Sufficiently many systems have been imaged that we discuss disk properties in scattered, polarized light in terms of groups defined by the IR spectral energy distribution. We find novel phenomena in many of the disks, including spiral density waves, and discuss the disks in terms of clearing mechanisms. Some of the disks have sufficient data to map the dust and gas components, including water ice dissociation products.

Context. We previously reported the direct detection of a low mass companion at a projected separation of 55±2 AU around the B9 type star κ Andromedae. The properties of the system (mass ratio, separation) make it a benchmark for the understanding of the formation and evolution of gas giant planets and brown dwarfs on wide-orbits. Aims. We present new angular differential imaging (ADI) images of the system at 2.146 (Ks), 3.776 (L’), 4.052 (NB 4.05) and 4.78 μm (M’) obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We aim to determine the near-infrared spectral energy distribution (SED) of the companion and use it to characterize the object. Methods. We used analysis methods adapted to ADI to extract the companion flux. We compared the photometry of the object to reference young/old objects and to a set of seven PHOENIX-based atmospheric models of cool objects accounting for the formation of dust. We used evolutionary models to derive mass estimates considering a wide range of plausible initial conditions. Finally, we used dedicated formation models to discuss the possible origin of the companion. Results. We derive a more accurate J = 15.86 ± 0.21, H = 14.95 ± 0.13, Ks = 14.32 ± 0.09 mag for κ And b. We redetect the companion in all our high contrast observations. We confirm previous contrasts obtained at Ks and L’ band. We derive NB 4.05 = 13.0 ± 0.2 and M′ = 13.3 ± 0.3 mag and estimate Log10(L/L ) = −3.76 ± 0.06. Atmospheric models yield Teff = 1900+100 −200 K. They do not set constrains on the surface gravity. “Hot-start” evolutionary models predict masses of 14+25 −2 MJup based on the luminosity and temperature estimates, and considering a conservative age range for the system (30+120 −10 Myr). “warm-start” evolutionary tracks constrain the mass to M ≥ 11MJup. Conclusions. The mass of κ Andromedae b mostly falls in the brown-dwarf regime, due to remaining uncertainties in age and mass-luminosity models. According to the formation models, disk instability in a primordial disk could account for the position and a wide range of plausible masses of κ And b.

We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of similar to 10(5) at 1 '' and similar to 10(6) beyond 2 '' around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, beta Pictoris (similar to 20 Myr), AB Doradus (similar to 100 Myr), Columba (similar to 30 Myr), Tucana-Horogium (similar to 30 Myr), and TW Hydrae (similar to 10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca II HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets,. And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper.

Context.We previously reported the direct detection of a low-mass companion at a projected separation of 55 ± 2 AU around the B9-type star κ Andromedae.The properties of the system (mass ratio, separation) make it a benchmark for understanding the formation and evolution of gas giant planets and brown dwarfs on wide orbits.Aims.We present new angular differential imaging (ADI) images of the system at 2.146 (K s ), 3.776 (L ), 4.052 (NB_4.05),and 4.78 µm (M ) obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument.We aim to determine the near-infrared spectral energy distribution of the companion and use it to characterize the object.Methods.We used analysis methods adapted to ADI to extract the companion flux.We compared the photometry of the object to reference young, and old objects and to a set of seven PHOENIX-based atmospheric models of cool objects accounting for the formation of dust.We used evolutionary models to derive mass estimates considering a wide range of plausible initial conditions.Finally, we used dedicated formation models to discuss the possible origin of the companion.Results.We derive a more accurate J = 15.86 ± 0.21, H = 14.95 ± 0.13, K s = 14.32 ± 0.09 mag for κ And b.We detect the companion in all our high-contrast observations.We confirm previous contrasts obtained at K s and L band.We derive NB_4.05 = 13.0 ± 0.2, and M = 13.3 ± 0.3 mag and estimate log 10 (L/L ) = -3.76± 0.06.Atmospheric models yield T eff = 1900 +100 -200 K.They do not set any constraint on the surface gravity."Hotstart" evolutionary models predict masses of 14 +25-2 M Jup based on the luminosity and temperature estimates, and when considering a conservative age range for the system (30 +120 -10 Myr), "warm-start" evolutionary tracks constrain the mass to M ≥ 10 M Jup .Conclusions.The mass of κ Andromedae b mostly falls in the brown-dwarf regime, owing to remaining uncertainties in age and in mass-luminosity models.According to the formation models, disk instability in a primordial disk may account for the position and a wide range of plausible masses of κ And b.

Context. We previously reported the direct detection of a low mass companion at a projected separation of 55 2 AU around the B9 type star Andromedae. The properties of the system (mass ratio, separation) make it a benchmark for the understanding of the formation and evolution of gas giant planets and brown dwarfs on wide-orbits. Aims. We present new angular di erential imaging (ADI) images of the system at 2.146 (Ks), 3.776 (L’), 4.052 (NB 4:05) and 4.78 m (M’) obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We aim to determine the near-infrared spectral energy distribution (SED) of the companion and use it to characterize the object. Methods. We used analysis methods adapted to ADI to extract the companion flux. We compared the photometry of the object to reference young/old objects and to a set of seven PHOENIX-based atmospheric models of cool objects accounting for the formation of dust. We used evolutionary models to derive mass estimates considering a wide range of plausible initial conditions. Finally, we used dedicated formation models to discuss the possible origin of the companion. Results. We derive a more accurate J = 15:86 0:21, H = 14:95 0:13, Ks = 14:32 0:09 mag for And b. We redetect the companion in all our high contrast observations. We confirm previous contrasts obtained at Ks and L’ band. We derive NB 4:05 = 13:0 0:2 and M 0 = 13:3 0:3 mag and estimate Log10(L=L ) = 3:76 0:06. Atmospheric models yield Te = 1900 +100 K. They do not set constrains on the surface gravity. “Hot-start” evolutionary models predict masses of 14 +25 MJup based on the luminosity and temperature estimates, and considering a conservative age range for the system (30 +120 Myr). “warm-start” evolutionary tracks constrain the mass to M 11MJup. Conclusions. The mass of Andromedae b mostly falls in the brown-dwarf regime, due to remaining uncertainties in age and mass-luminosity models. According to the formation models, disk instability in a primordial disk could account for the position and a wide range of plausible masses of And b.

We conduct a statistical analysis of a combined sample of direct imaging data, totalling nearly 250 stars. The stars cover a wide range of ages and spectral types, and include five detections (kappa And b, two similar to 60 M-J brown dwarf companions in the Pleiades, PZ Tel B, and CD-35 2722B). For some analyses we add a currently unpublished set of SEEDS observations, including the detections GJ 504b and GJ 758B. We conduct a uniform, Bayesian analysis of all stellar ages using both membership in a kinematic moving group and activity/rotation age indicators. We then present a new statistical method for computing the likelihood of a substellar distribution function. By performing most of the integrals analytically, we achieve an enormous speedup over brute-force Monte Carlo. We use this method to place upper limits on the maximum semimajor axis of the distribution function derived from radialvelocity planets, finding model-dependent values of similar to 30-100 AU. Finally, we model the entire substellar sample, from massive brown dwarfs to a theoretically motivated cutoff at similar to 5 M-J, with a single power-law distribution. We find that p(M, a) alpha M-0.65 +/- 0.60 alpha(-0.85 +/- 0.39) (1 sigma errors) provides an adequate fit to our data, with 1.0%-3.1% (68% confidence) of stars hosting 5-70 M-J companions between 10 and 100 AU. This suggests that many of the directly imaged exoplanets known, including most (if not all) of the low-mass companions in our sample, formed by fragmentation in a cloud or disk, and represent the low-mass tail of the brown dwarfs.

The existence of silica within several debris disks has been suggested. Data on both the spectroscopy and annealing conditions of the various polymorphs of silica need to be investigated, as these data are lacking and incomplete in the literature. We investigate the annealing conditions of silica and prepare various types of silica, including alpha-cristobalite, alpha-quartz, coesite, stishovite, and fused quartz, which are natural, synthetic, or commercial samples. This paper presents a new study of both the spectroscopy of relevant silica polymorphs and the conditions under which they form. We compare the results to previous studies and find that there are discrepancies. The interesting result of features similar to those of forsterite should be highlighted, where alpha-cristobalite and coesite showed similar peaks at 16, 33, and 69 mu m as forsterite. The 69 mu m band for alpha-cristobalite is especially very broad and strong and shifts largely to a shorter wavelengths under cooling to low temperatures. The band for coesite, however, is very sharp and shifts only a small amount to longer wavelengths under cooling to low temperatures. We discuss the possibility of silica detection around debris disks.

Several exoplanets have recently been imaged at wide separations of > 10 AU from their parent stars. These span a limited range of ages ( < 50 Myr) and atmospheric properties, with temperatures of 800–1800 K and very red colors ( J − H > 0 . 5 mag), implying thick cloud covers. Furthermore, substantial model uncertainties exist at these young ages due to the unknown initial conditions at formation, which can lead to an order of magnitude of uncertainty in the modeled planet mass. Here, we report the direct-imaging discovery of a Jovian exoplanet around the Sun-like star GJ 504, detected as part of the SEEDS survey. The system is older than all other known directly imaged planets; as a result, its estimated mass remains in the planetary regime independent of uncertainties related to choices of initial conditions in the exoplanet modeling. Using the most common exoplanet cooling model, and given the system age of 160 +350 − 60 Myr, GJ 504b has an estimated mass of 4 +4 . 5 − 1 . 0 Jupiter masses, among the lowest of directly imaged planets. Its projected separation of 43.5 AU exceeds the typical outer boundary of ∼ 30 AU predicted for the core accretion mechanism. GJ 504b is also significantly cooler (510 +30 − 20 K) and has a bluer color ( J − H = − 0 . 23 mag) than previously imaged exoplanets, suggesting a largely cloud-free atmosphere accessible to spectroscopic characterization. Thus, it has the potential of providing novel insights into the origins of giant planets as well as their atmospheric properties.

We present the first near-IR scattered light detection of the transitional disk associated with the Herbig Ae star MWC 758 using data obtained as part of the Strategic Exploration of Exoplanets and Disks with Subaru, and 1.1 micron HST/NICMOS data. While sub-millimeter studies suggested there is a dust-depleted cavity with r=0.35, we find scattered light as close as 0.1 (20-28 AU) from the star, with no visible cavity at H, K', or Ks. We find two small-scaled spiral structures which asymmetrically shadow the outer disk. We model one of the spirals using spiral density wave theory, and derive a disk aspect ratio of h 0.18, indicating a dynamically warm disk. If the spiral pattern is excited by a perturber, we estimate its mass to be 5+3,-4 Mj, in the range where planet filtration models predict accretion continuing onto the star. Using a combination of non-redundant aperture masking data at L' and angular differential imaging with Locally Optimized Combination of Images at K' and Ks, we exclude stellar or massive brown dwarf companions within 300 mas of the Herbig Ae star, and all but planetary mass companions exterior to 0.5. We reach 5-sigma contrasts limiting companions to planetary masses, 3-4 MJ at 1.0 and 2 MJ at 1.55 using the COND models. Collectively, these data strengthen the case for MWC 758 already being a young planetary system.

We describe Algorithms for Calibration, Optimized Registration, and Nulling the Star in Angular Differential Imaging (ACORNS-ADI), a new, parallelized software package to reduce high-contrast imaging data, and its application to data from the SEEDS survey. We implement several new algorithms, including a method to register saturated images, a trimmed mean for combining an image sequence that reduces noise by up to similar to 20%, and a robust and computationally fast method to compute the sensitivity of a high-contrast observation everywhere on the field of view without introducing artificial sources. We also include a description of image processing steps to remove electronic artifacts specific to Hawaii2-RG detectors like the one used for SEEDS, and a detailed analysis of the Locally Optimized Combination of Images (LOCI) algorithm commonly used to reduce high-contrast imaging data. ACORNS-ADI is written in python. It is efficient and open-source, and includes several optional features which may improve performance on data from other instruments. ACORNS-ADI requires minimal modification to reduce data from instruments other than HiCIAO. It is freely available for download at www.github.com/t-brandt/acorns-adi under a Berkeley Software Distribution (BSD) license.

J. Hashimoto1, R. Dong2, T. Kudo3, M. Honda4, M. K. McClure5, Z. Zhu2, T. Muto6, J. Wisniewski1, L. Abe7, W. Brandner8, T. Brandt2, J. Carson9, S. Egner3, M. Feldt8, M. Fukagawa10, M. Goto11, C. A. Grady12,13, O. Guyon3, Y. Hayano3, M. Hayashi14, S. Hayashi3, T. Henning8, K. Hodapp15, M. Ishii3, M. Iye14, M. Janson2, R. Kandori14, G. Knapp2, N. Kusakabe14, M. Kuzuhara14,16,17, J. Kwon14,18, T. Matsuo19, S. Mayama20, M. W. McElwain12, S. Miyama21, J.-I. Morino14, A. Moro-Martin2,22, T. Nishimura3, T.-S. Pyo3, G. Serabyn23, T. Suenaga14,18, H. Suto14, R. Suzuki14, Y. Takahashi14,24, M. Takami25, N. Takato3, H. Terada3, C. Thalmann26, D. Tomono3, E. L. Turner2,27, M. Watanabe28, T. Yamada29, H. Takami3, T. Usuda3, and M. Tamura14 1 H. L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks St Norman, OK 73019, USA; jun.hashimoto@ou.edu 2 Department of Astrophysical Sciences, Princeton University, NJ 08544, USA 3 Subaru Telescope, 650 North A’ohoku Place, Hilo, HI 96720, USA 4 Kanagawa University, 2946 Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan 5 Department of Astronomy, The University of Michigan, 500 Church St., 830 Dennison Bldg., Ann Arbor, MI 48109, USA 6 Division of Liberal Arts, Kogakuin University, 1-24-2, Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8677, Japan 7 Laboratoire Hippolyte Fizeau, UMR6525, Universite de Nice Sophia-Antipolis, 28, avenue Valrose, F-06108 Nice Cedex 2, France 8 Max Planck Institute for Astronomy, Heidelberg, Germany 9 Department of Physics and Astronomy, College of Charleston, 58 Coming St., Charleston, SC 29424, USA 10 Osaka University, 1-1, Machikaneyama, Toyonaka, Osaka 560-0043, Japan 11 Universitäts-Sternwarte München Scheinerstr. 1, D-81679 Munich, Germany 12 Exoplanets and Stellar Astrophysics Laboratory, Code 667, Goddard Space Flight Center, Greenbelt, MD 20771, USA 13 Eureka Scientific, 2452 Delmer, Suite 100, Oakland, CA 96002, USA 14 National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 15 University of Hawaii, 640 North A’ohoku Place, Hilo, HI 96720, USA 16 Department of Earth and Planetary Science, University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan 17 Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan 18 Department of Astronomical Science, Graduate University for Advanced Studies (Sokendai), Tokyo 181-8588, Japan 19 Department of Astronomy, Kyoto University, Kita-shirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan 20 The Graduate University for Advanced Studies, Shonan International Village, Hayama-cho, Miura-gun, Kanagawa 240-0193, Japan 21 Hiroshima University, 1-3-2 Kagamiyama, Higashi-Hiroshima 739-8511, Japan 22 Department of Astrophysics, CAB-CSIC/INTA, E-28850 Torrej’on de Ardoz, Madrid, Spain 23 Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA 24 Department of Astronomy, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan 25 Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan 26 Astronomical Institute “Anton Pannekoek,” University of Amsterdam, Postbus 94249, 1090 GE, Amsterdam, The Netherlands 27 Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, Kashiwa 227-8568, Japan 28 Department of Cosmosciences, Hokkaido University, Sapporo 060-0810, Japan 29 Astronomical Institute, Tohoku University, Aoba, Sendai 980-8578, Japan