scholarly journals GravityCam: Wide-field high-resolution high-cadence imaging surveys in the visible from the ground

2018 ◽  
Vol 35 ◽  
Author(s):  
C. Mackay ◽  
M. Dominik ◽  
I. A. Steele ◽  
C. Snodgrass ◽  
U. G. Jørgensen ◽  
...  
Keyword(s):  
High Resolution ◽  
Adaptive Optics ◽  
High Speed ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Oort Cloud ◽  
Compact Objects ◽  
Image Resolution ◽  
Wide Field ◽  
Data Set

AbstractGravityCam is a new concept of ground-based imaging instrument capable of delivering significantly sharper images from the ground than is normally possible without adaptive optics. Advances in optical and near-infrared imaging technologies allow images to be acquired at high speed without significant noise penalty. Aligning these images before they are combined can yield a 2.5–3-fold improvement in image resolution. By using arrays of such detectors, survey fields may be as wide as the telescope optics allows. Consequently, GravityCam enables both wide-field high-resolution imaging and high-speed photometry. We describe the instrument and detail its application to provide demographics of planets and satellites down to Lunar mass (or even below) across the Milky Way. GravityCam is also suited to improve the quality of weak shear studies of dark matter distribution in distant clusters of galaxies and multiwavelength follow-ups of background sources that are strongly lensed by galaxy clusters. The photometric data arising from an extensive microlensing survey will also be useful for asteroseismology studies, while GravityCam can be used to monitor fast multiwavelength flaring in accreting compact objects and promises to generate a unique data set on the population of the Kuiper belt and possibly the Oort cloud.

GeMS/GSAOI near-infrared imaging of z ∼ 0.3 BL Lacs

2019 ◽  
Vol 15 (S356) ◽  
pp. 372-372
Author(s):  
Susan Ridgway
Keyword(s):  
High Resolution ◽  
Adaptive Optics ◽  
Galaxy Formation ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Morphological Evidence ◽  
Host Galaxies ◽  
The Galaxy ◽  
Nuclear Component ◽  
Bl Lacs

AbstractBright quasars at low z have generally been found in massive, evolved host galaxies, consistent with formation at early epochs. However, deep, high resolution, multicolor imaging of some quasar hosts have found morphological evidence of tidal tails and colors indicative of active star formation. These results are consistent with theories of galaxy formation and evolution in which merger processes trigger the activation of the quasar phase, and energetic feedback is essential. Understanding the role the black hole population plays in the galaxy formation process is important, but imaging the host galaxies around bright quasars is difficult because of the contribution of the bright nuclei. Very high resolution, deep imaging is necessary to successfully remove the nuclear component. We made high-resolution near-infrared images of several bright z ˜ 0.3 BL Lacs with the Gemini Multi-Conjugate Adaptive Optics System (GeMS)/GSAOI in order to study their host galaxies. We will present the results of this imaging with the 1 arcmin AO-corrected field provided by GeMS/GSAOI and compare with available HST imaging available in the archive.

scholarly journals Near-Infrared Imaging by a Schmidt Telescope

1994 ◽  
Vol 161 ◽  
pp. 89-90
Author(s):  
K. Yanagisawa ◽  
N. Itoh ◽  
T. Ichikawa ◽  
K. Tarusawa ◽  
M. Ueno
Keyword(s):  
Thermal Radiation ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Image Resolution ◽  
Wide Field ◽  
Schmidt Telescope ◽  
Large Format ◽  
Array Camera ◽  
Field Imaging ◽  
Wide Field Imaging

We have carried out wide field imaging observations in the near-infrared (J, H and K′ band) with a large format array camera attached to the prime focus of the 105 cm Schmidt telescope at Kiso Observatory. The image resolution, limiting magnitudes and the effect of thermal radiation are discussed.

scholarly journals Adaptive Optics Imaging of Circumstellar Environments

2004 ◽  
Vol 221 ◽  
pp. 307-312
Author(s):  
Dániel Apai ◽  
Ilaria Pascucci ◽  
Hongchi Wang ◽  
Wolfgang Brandner ◽  
Thomas Henning ◽  
...  
Keyword(s):  
High Resolution ◽  
Adaptive Optics ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Circumstellar Disks ◽  
Circumstellar Envelope ◽  
High Contrast ◽  
Contrast Imaging ◽  
High Contrast Imaging ◽  
Circumstellar Environments

We present results from our high-resolution, high-contrast imaging campaign targeting the circumstellar environments of young, nearby stars of different masses. The observations have been conducted using the ALFA/CA 3.5m and NACO UT4/VLT adaptive optics systems. In order to enhance the contrast we applied the methods PSF-subtraction and polarimetric differential imaging (PDI). The observations of young stars yielded the identification of numerous new companion candidates, the most interesting one being ∼ 0.5″ from FU Ori. We also obtained high-resolution near-infrared imaging of the circumstellar envelope of SU Aur and AB Aur. Our PDI of the TW Hya circumstellar disk traced back the disk emission as close as 0.1″ ≃ 6 AU from the star, the closest yet. Our results demonstrate the potential of the adaptive optics systems in achieving high-resolution and high-contrast imaging and thus in the study of circumstellar disks, envelopes and companions.

scholarly journals Orbital and atmospheric characterization of the planet within the gap of the PDS 70 transition disk

2018 ◽  
Vol 617 ◽  
pp. L2 ◽  
Author(s):  
A. Müller ◽  
M. Keppler ◽  
Th. Henning ◽  
M. Samland ◽  
G. Chauvin ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Near Infrared ◽  
Direct Detection ◽  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
Infrared Range ◽  
Data Set ◽  
Cloud Properties ◽  
Spectrophotometric Data ◽  
First Time

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.

scholarly journals Substellar and low-mass dwarf identification with near-infrared imaging space observatories

2018 ◽  
Vol 620 ◽  
pp. A132 ◽  
Author(s):  
B. W. Holwerda ◽  
J. S. Bridge ◽  
R. Ryan ◽  
M. A. Kenworthy ◽  
N. Pirzkal ◽  
...  
Keyword(s):  
Near Infrared ◽  
Infrared Imaging ◽  
High Redshift ◽  
Brown Dwarfs ◽  
Wide Field ◽  
Space Telescope ◽  
Low Mass ◽  
Space Observatories ◽  
Broad Type ◽  
Selection Of

Aims. We aim to evaluate the near-infrared colors of brown dwarfs as observed with four major infrared imaging space observatories: the Hubble Space Telescope (HST), the James Webb Space Telescope (JWST), the Euclid mission, and the WFIRST telescope. Methods. We used the SPLAT SPEX/ISPEX spectroscopic library to map out the colors of the M-, L-, and T-type dwarfs. We have identified which color–color combination is optimal for identifying broad type and which single color is optimal to then identify the subtype (e.g., T0-9). We evaluated each observatory separately as well as the narrow-field (HST and JWST) and wide-field (Euclid and WFIRST) combinations. Results. The Euclid filters perform equally well as HST wide filters in discriminating between broad types of brown dwarfs. WFIRST performs similarly well, despite a wider selection of filters. However, subtyping with any combination of Euclid and WFIRST observations remains uncertain due to the lack of medium, or narrow-band filters. We argue that a medium band added to the WFIRST filter selection would greatly improve its ability to preselect brown dwarfs its imaging surveys. Conclusions. The HST filters used in high-redshift searches are close to optimal to identify broad stellar type. However, the addition of F127M to the commonly used broad filter sets would allow for unambiguous subtyping. An improvement over HST is one of two broad and medium filter combinations on JWST: pairing F140M with either F150W or F162M discriminates very well between subtypes.

Deep Near-Infrared Surveys and Young Brown Dwarf Populations in Star-Forming Regions

2003 ◽  
Vol 211 ◽  
pp. 87-90
Author(s):  
M. Tamura ◽  
T. Naoi ◽  
Y. Oasa ◽  
Y. Nakajima ◽  
C. Nagashima ◽  
...  
Keyword(s):  
High Resolution ◽  
Adaptive Optics ◽  
Near Infrared ◽  
Brown Dwarf ◽  
Ir Camera ◽  
Star Forming ◽  
Star Forming Regions ◽  
New Instrument ◽  
Infrared Surveys ◽  
Low Mass

We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.

scholarly journals Structural and Morphological Properties of Ultraluminous Infrared Galaxies at 1 < z < 3

2015 ◽  
Vol 24 (3) ◽  
Author(s):  
Guanwen Fang ◽  
Zhongyang Ma ◽  
Yang Chen ◽  
Xu Kong
Keyword(s):  
High Resolution ◽  
Near Infrared ◽  
Hubble Space Telescope ◽  
Morphological Properties ◽  
Wide Field ◽  
High Resolution Imaging ◽  
Infrared Galaxies ◽  
Morphology And Structure ◽  
Ultraluminous Infrared Galaxies ◽  
Resolution Imaging

AbstractUsing the Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) near-infrared high-resolution imaging from the 3D-HST survey, we analyze the morphology and structure of 502 ultraluminous infrared galaxies (ULIRGs;

scholarly journals 3.3. Circumnuclear regions of active and non-active barred galaxies

1998 ◽  
Vol 184 ◽  
pp. 93-94
Author(s):  
J.H. Knapen
Keyword(s):  
High Resolution ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Seyfert Galaxy ◽  
Active Galaxies ◽  
Necessary Condition ◽  
Nuclear Activity ◽  
Barred Galaxies ◽  
Galaxy Cores

I discuss the role of galactic bars in the fuelling of (circum)nuclear activity. Since the majority of all galaxies are barred, the presence of a bar in a Seyfert galaxy cannot be the sole reason for their activity, although it appears to be a necessary condition for activity. Two options for further work are being explored, high-resolution near-infrared imaging of samples of active and non-active galaxies, and detailed case studies of selected galaxy cores.

Sign in / Sign up

Export Citation Format

Share Document