Tracking the surface figure error of the pick off mirror throughout build and environmental testing of the focus and alignment mechanism qualification unit of the near-infrared camera of JWST

ABSTRACT Only a small number of exoplanets have been identified in stellar cluster environments. We initiated a high angular resolution direct imaging search using the Hubble Space Telescope (HST) and its Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) instrument for self-luminous giant planets in orbit around seven white dwarfs in the 625 Myr old nearby (≈45 pc) Hyades cluster. The observations were obtained with Near-Infrared Camera 1 (NIC1) in the F110W and F160W filters, and encompass two HST roll angles to facilitate angular differential imaging. The difference images were searched for companion candidates, and radially averaged contrast curves were computed. Though we achieve the lowest mass detection limits yet for angular separations ≥0.5 arcsec, no planetary mass companion to any of the seven white dwarfs, whose initial main-sequence masses were >2.8 M⊙, was found. Comparison with evolutionary models yields detection limits of ≈5–7 Jupiter masses (MJup) according to one model, and between 9 and ≈12 MJup according to another model, at physical separations corresponding to initial semimajor axis of ≥5–8 au (i.e. before the mass-loss events associated with the red and asymptotic giant branch phase of the host star). The study provides further evidence that initially dense cluster environments, which included O- and B-type stars, might not be highly conducive to the formation of massive circumstellar discs, and their transformation into giant planets (with m ≥ 6 MJup and a ≥6 au). This is in agreement with radial velocity surveys for exoplanets around G- and K-type giants, which did not find any planets around stars more massive than ≈3 M⊙.

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PANIC: a near-infrared camera for the Magellan telescopes

10.1117/12.551828 ◽

2004 ◽

Cited By ~ 60

Author(s):

Paul Martini ◽

S. E. Persson ◽

David C. Murphy ◽

Christoph Birk ◽

Stephen A. Shectman ◽

...

Keyword(s):

Near Infrared ◽

Infrared Camera

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Real time injecting device with automated robust vein detection using near infrared camera and live video

2017 IEEE Global Humanitarian Technology Conference (GHTC) ◽

10.1109/ghtc.2017.8239298 ◽

2017 ◽

Cited By ~ 2

Author(s):

Tamim Ahmed ◽

Khandker Sadia Rahman ◽

Sk Subrina Shawlin ◽

Mohammad Hasan ◽

Arnab Bhattacharjee ◽

...

Keyword(s):

Real Time ◽

Near Infrared ◽

Infrared Camera ◽

Live Video

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Effective background subtraction algorithm for food inspection using a low-cost near infrared camera

2017 Open Conference of Electrical, Electronic and Information Sciences (eStream) ◽

10.1109/estream.2017.7950322 ◽

2017 ◽

Cited By ~ 2

Author(s):

Paulius Tumas ◽

Arturas Serackis

Keyword(s):

Background Subtraction ◽

Near Infrared ◽

Low Cost ◽

Infrared Camera ◽

Food Inspection

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469 ASSESSMENT OF PERFUSION OF GASTRIC CONDUIT AND PROXIMAL ESOPHAGEAL STUMP BY INDOCYANINE GREEN FLUORESCENCE IMAGING IN PATIENTS UNDERGOING ESOPHAGECTOMY

Diseases of the Esophagus ◽

10.1093/dote/doab052.469 ◽

2021 ◽

Vol 34 (Supplement_1) ◽

Author(s):

Subramanyeshwar Rao Thammineedi

Keyword(s):

Indocyanine Green ◽

Fluorescence Imaging ◽

Visual Inspection ◽

Near Infrared ◽

Infrared Camera ◽

Visual Assessment ◽

Transhiatal Esophagectomy ◽

Gastric Conduit ◽

Indocyanine Green Fluorescence ◽

Laparoscopic Assisted

Abstract Post esophagectomy anastomotic leakage and stricture are crucial factors in determining morbidity and mortality. Good vascularity of the gastric conduit is essential to avoid this complications. This prospective study assesses the utility of intraoperative indocyanine green (ICG) fluorescence imaging to determine gastric conduit vascularity in patients undergoing esophagectomy. Methods Thirteen consecutive patients who were undergoing esophagectomy for carcinoma middle, lower third esophagus or gastro-esophageal junction from August 2019 to September 2019, were included. Three patients underwent laparoscopic-assisted transhiatal esophagectomy, ten thoraco-laparoscopic assisted esophagectomy. Reconstruction was done by gastric pull up via posterior mediastinal route. Vascularity of gastric conduit was assessed by the near-infrared camera using ICG. Results On visual assessment of perfusion at the tip of gastric conduit, it was dusky in 11 patients, pink in two. Fuorescence imaging showed inadequate perfusion at the tip of conduit in 12 patients, needing revision. In one patient visual inspection showed adequate perfusion, but ICG disclosed poor vascularity requiring revision of the conduit’s tip. Resection of the devitalized portion of the proximal esophageal stump was needed in 5 patients both by visual and ICG assessment. The median time to appearance of blush from the time of injection of dye was 15 seconds (10 to 23 seconds). Conclusion Visual inspection of the gastric conduit vascularity can underestimate perfusion and hence can compromise resection of the devitalized part. ICG fluorescence imaging is more objective and promising means to ascertain the vascularity of gastric conduit during an esophagectomy. It could complement the visual inspection to decide the site of anastomosis.

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