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Author (up) Wampfler, S. F.; Herczeg, G. J.; Bruderer, S.; Benz, A. O.; van Dishoeck, E. F.; Kristensen, L. E.; Visser, R.; Doty, S. D.; Melchior, M.; van Kempen, T. A.; Yıldız, U. A.; Dedes, C.; Goicoechea, J. R.; Baudry, A.; Melnick, G.; Bachiller, R.; Benedettini, M.; Bergin, E.; Bjerkeli, P.; Blake, G. A.; Bontemps, S.; Braine, J.; Caselli, P.; Cernicharo, J.; Codella, C.; Daniel, F.; di Giorgio, A. M.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Giannini, T.; de Graauw, Th.; Helmich, F.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Johnstone, D.; Jørgensen, J. K.; Larsson, B.; Lis, D.; Liseau, R.; Marseille, M.; Mc Coey, C.; Neufeld, D.; Nisini, B.; Olberg, M.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Shipman, R.; Tafalla, M.; van der Tak, F. F. S.; Wyrowski, F.; Roelfsema, P.; Jellema, W.; Dieleman, P.; Caux, E.; Stutzki, J.
Title Herschel observations of the hydroxyl radical (OH) in young stellar objects Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume 521 Issue Pages L36
Keywords HEB mixer applications, HIFI, Herschel, astrochemistry / stars: formation / ISM: molecules / ISM: jets and outflows / ISM: individual objects: HH 46
Abstract Aims. “Water In Star-forming regions with Herschel” (WISH) is a Herschel key program investigating the water chemistry in young stellar objects (YSOs) during protostellar evolution. Hydroxyl (OH) is one of the reactants in the chemical network most closely linked to the formation and destruction of H2O. High-temperature (T 250 K) chemistry connects OH and H2O through the OH + H2 H2O + H reactions. Formation of H2O from OH is efficient in the high-temperature regime found in shocks and the innermost part of protostellar envelopes. Moreover, in the presence of UV photons, OH can be produced from the photo-dissociation of H2O through H2O + γUV OH + H.

Methods. High-resolution spectroscopy of the 163.12 μm triplet of OH towards HH 46 and NGC 1333 IRAS 2A was carried out with the Heterodyne Instrument for the Far Infrared (HIFI) on board the Herschel Space Observatory. The low- and intermediate-mass protostars HH 46, TMR 1, IRAS 15398-3359, DK Cha, NGC 7129 FIRS 2, and NGC 1333 IRAS 2A were observed with the Photodetector Array Camera and Spectrometer (PACS) on Herschel in four transitions of OH and two [O i] lines.

Results. The OH transitions at 79, 84, 119, and 163 μm and [O i] emission at 63 and 145μm were detected with PACS towards the class I low-mass YSOs as well as the intermediate-mass and class I Herbig Ae sources. No OH emission was detected from the class 0 YSO NGC 1333 IRAS 2A, though the 119 μm was detected in absorption. With HIFI, the 163.12 μm was not detected from HH 46 and only tentatively detected from NGC 1333 IRAS 2A. The combination of the PACS and HIFI results for HH 46 constrains the line width (FWHM 11 km s-1) and indicates that the OH emission likely originates from shocked gas. This scenario is supported by trends of the OH flux increasing with the [O i] flux and the bolometric luminosity, as found in our sample. Similar OH line ratios for most sources suggest that OH has comparable excitation temperatures despite the different physical properties of the sources.
Address
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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Notes Approved no
Call Number Serial 1103
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Author (up) Zubkova, E.; An, P.; Kovalyuk, V.; Korneev, A.; Ferrari, S.; Pernice, W.; Goltsman, G.
Title Optimization of contra-directional coupler based on silicon nitride Bragg rib waveguide Type Conference Article
Year 2018 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1124 Issue Pages 051048
Keywords Bragg waveguide, Si3N4
Abstract We report on the development and fabrication of a contra-directional coupler based on the Bragg waveguide on Si3N4 platform. Transmitted and reflected by the contra-directional coupler spectra were measured. The reflected spectra exactly matches the one notched by the main channel of the coupler. Losses are about 3dB, coupling to the directing branch of the coupler is practically lossless. FWHM of the transmitted (reflected) spectra is 3.46 nm.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1195
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Author (up) Zubkova, E.; An, P.; Kovalyuk, V.; Korneev, A.; Ferrari, S.; Pernice, W.; Goltsman, G.
Title Integrated Bragg waveguides as an efficient optical notch filter on silicon nitride platform Type Conference Article
Year 2017 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 917 Issue Pages 062042
Keywords Si3N4, Bragg waveguides
Abstract We modeled and fabricated integrated optical Bragg waveguides on a silicon nitride (Si3N4) platform. These waveguides would serve as efficient notch-filters with the desired characteristics. Transmission spectra of the fabricated integrated notch filters have been measured and attenuation at the desired wavelength of 1550 nm down to -43 dB was observed. Performance of the filters has been studied depending on different parameters, such as pitch, filling factor, and height of teeth of the Bragg grating
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Notes Approved no
Call Number RPLAB @ kovalyuk @ Serial 1141
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Author (up) Zubkova, E.; An, P.; Kovalyuk, V.; Korneev, A.; Goltsman, G.
Title Integrated Bragg waveguides as an efficient optical notch filter on silicon nitride platform Type Conference Article
Year 2017 Publication Proc. SPBOPEN Abbreviated Journal Proc. SPBOPEN
Volume Issue Pages 449-450
Keywords Bragg waveguides
Abstract We modeled and fabricated integrated optical Bragg waveguides on a silicon nitride (Si3N4) platform. Transmission spectra of the integrated notch filter has been measured and attenuation at the desired wavelength of 1550 nm down to -43 dB was observed.
Address St. Petersburg, Russia
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Notes Duplicated as 1141 Approved no
Call Number Serial 1257
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Author (up) Zubkova, E.; Golikov, A.; An, P.; Kovalyuk, V.; Korneev, A.; Ferrari, S.; Pernice, W.; Goltsman, G.
Title CWDM demultiplexer using anti-reflection, contra-directional couplers based on silicon nitride rib waveguide Type Conference Article
Year 2019 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1410 Issue Pages 012179
Keywords coarse wavelength-division multiplexing, Si3N4 rib waveguide
Abstract We report on the development and fabrication of a 9-channel coarse wavelength-division multiplexing for telecommunication wavelengths (1550 nm) using anti-reflection contra-directional couplers, based on silicon nitride (Si3N4) rib waveguide. The transmitted and reflected spectrum in each channel of the demultiplexer were measured. The average full width at half maximum of the transmitted (reflected) spectra is about 3 nm.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1183
Permanent link to this record