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| Author | Zhang, W.; Miao, W.; Yao, Q. J.; Lin, Z. H.; Shi, S. C.; Gao, J. R.; Goltsman, G. N. | ||||
| Title | Spectral response and noise temperature of a 2.5 THz spiral antenna coupled NbN HEB mixer | Type | Journal Article | ||
| Year | 2012 | Publication | Phys. Procedia | Abbreviated Journal | Phys. Procedia |
| Volume | 36 | Issue | Pages | 334-337 | |
| Keywords | NbN HEB mixer | ||||
| Abstract | We report on a 2.5 THz spiral antenna coupled NbN hot electron bolometer (HEB) mixers, fabricated with in-situ process. The receiver noise temperature with lowest value of 1180 K is in good agreement with calculated quantum efficiency factor as a function of bias voltage. In addition, the measured spectral response of the spiral antenna coupled NbN HEB mixer shows broad frequency coverage of 0.8-3 THz, and corrected response for optical losses, FTS, and coupling efficiency between antenna and bolometer falls with frequency due to diffraction-limited beam of lens/antenna combination. | ||||
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| ISSN | 1875-3892 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1381 | |||
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| Author | Pentin, I. V.; Smirnov, A. V.; Ryabchun, S. A.; Ozhegov, R. V.; Gol’tsman, G. N.; Vaks, V. L.; Pripolzin, S. I.; Pavel’ev, D. G.; Koshurinov, Y. I.; Ivanov, A. S. | ||||
| Title | Semiconducting superlattice as a solid-state terahertz local oscillator for NbN hot-electron bolometer mixers | Type | Journal Article | ||
| Year | 2012 | Publication | Tech. Phys. | Abbreviated Journal | Tech. Phys. |
| Volume | 57 | Issue | 7 | Pages | 971-974 |
| Keywords | semiconducting superlattice frequency multiplier, NbN HEB mixers | ||||
| Abstract | We present the results of our studies of the semiconducting superlattice (SSL) frequency multiplier and its application as part of the solid state local oscillator (LO) in the terahertz heterodyne receiver based on a NbN hot-electron bolometer (HEB) mixer. We show that the SSL output power level increases as the ambient temperature is lowered to 4.2 K, the standard HEB operation temperature. | ||||
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| ISSN | 1063-7842 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1378 | |||
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| Author | Ozhegov, R. V.; Gorshkov, K. N.; Okunev, O. V.; Gol’tsman, G. N. | ||||
| Title | Superconducting hot-electron bolometer mixer as element of thermal imager matrix | Type | Journal Article | ||
| Year | 2010 | Publication | Tech. Phys. Lett. | Abbreviated Journal | Tech. Phys. Lett. |
| Volume | 36 | Issue | 11 | Pages | 1006-1008 |
| Keywords | HEB mixers | ||||
| Abstract | The possibility of using a matrix of sensitive elements on a 12-mm-diameter hyperhemispherical lens in a thermal imager operating in the terahertz range has been studied. Dimensions of a lens region acceptable for arrangement of the matrix, in which the receiver noise temperature varies within 16% of the mean value, are determined to be 3.3% of the lens diameter. Deviations of the main lobe of the directivity pattern are evaluated, which amount to ±1.25° relative to the direction toward the optimum position of a mixer. The fluctuation sensitivity of the receiver measured in experiment is 0.5 K at a frequency of 300 GHz. | ||||
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| ISSN | 1063-7850 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1390 | |||
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| Author | Palma, F.; Teppe, F.; Fatimy, A. E.; Green, R.; Xu, J.; Vachontin, Y.; Tredicucci, A.; Goltsman, G.; Knap, W. | ||||
| Title | THz communication system based on a THz quantum cascade laser and a hot electron bolometer | Type | Conference Article | ||
| Year | 2010 | Publication | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves | Abbreviated Journal | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves |
| Volume | Issue | Pages | 11623798 (1 to 2) | ||
| Keywords | QCL, HEB detector | ||||
| Abstract | We present the experimental study of the direct emission – detection system based on the THz Quantum Cascade Laser as a source and Hot Electron Bolometer (HEB) detector – in view of its application as an optical communication system. We show that the system can efficiently transmit the QCL Terahertz pulses. We estimate the maximal modulation speed of the system to be about several GHz and show that it is limited only by the QCL pulse power supply, detector amplifier and connection line/wires parameters. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1391 | |||
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| Author | Titova, N; Kardakova, A.; Tovpeko, N; Ryabchun, S.; Mandal, S.; Morozov, D.; Klemencic, G. M.; Giblin, S.R.; Williams, O. A.; Goltsman, G. N. | ||||
| Title | Superconducting diamond films as perspective material for direct THz detectors | Type | Abstract | ||
| Year | 2017 | Publication | Proc. 28th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 28th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 82 | ||
| Keywords | KID, HEB, superconducting diamond films, boron-doped diamond films, Al, TiN, Si substrates, NEP | ||||
| Abstract | Superconducting films with a high resistivity in the normal state have established themselves as the best materials for direct THz radiation sensors, such as kinetic inductance detectors (KIDs) [1] and hot electron bolometers (nano-HEBs) [2]. The primary characteristics of the future instrument such as the sensitivity and the response time are determined by the material parameters such as the electron-phonon (e-ph) interaction time, the electron density and the resistivity of the material. For direct detectors, such as KIDs and nano-HEBs, to provide a high sensitivity and low noise one prefer materials with long e-ph relaxation times and low values of the electron density. As a potential material for THz radiation detection we have studied superconducting diamond films. A significant interest to diamond for the development of electronic devices is due to the evolution of its properties with the boron dopant concentration. At a high boron doping concentration, n B ~5·10 20 cm -3 , diamond has been reported to become a superconducting with T c depending on the doping level. Our previous study of energy relaxation in single-crystalline boron-doped diamond films epitaxially grown on a diamond shows a remarkably slow energy-relaxation at low temperatures. The electron-phonon cooling time varies from 400 ns to 700 ns over the temperature range 2.2 K to 1.7 K [3]. In superconducting materials such as Al and TiN, traditionally used in KIDs, the e-ph cooling times at 1.7 K correspond to ~20 ns [4] and ~100 ns [5], correspondingly. Such a noticeable slow e-ph relaxation in boron-doped diamond, in combination with a low value of carrier density (~10 21 cm -3 ) in comparison with typical metals (~10 23 cm -3 ) and a high normal state resistivity (~1500 μΩ·cm) confirms a potential of superconducting diamond for superconducting bolometers and resonator detectors. However, the price and the small substrate growth are of single crystal diamond limit practical applications of homoepitaxial diamond films. As an alternative way with more convenient technology, one can employ heteroepitaxial diamond films grown on large-size Si substrates. Here we report about measurements of e-ph cooling times in superconducting diamond grown on silicon substrate and discuss our expectations about the applicability of boron-doped diamond films to superconducting detectors. Our estimation of limit value of noise-equivalent power (NEP) and the energy resolution of bolometer made from superconducting diamond is order 10 -17 W/Hz 1/2 at 2 K and the energy resolution is of 0.1 eV that corresponds to counting single-photon up to 15 um. The estimation was obtained by using the film thickness of 70 nm and ρ ~ 1500 μΩ·cm, and the planar dimensions that are chosen to couple bolometer with 75 Ω log-spiral antenna. Although the value of NEP is far yet from what might like to have for certain astronomical applications, we believe that it can be improved by a suitable fabrication process. Also the direct detectors, based on superconducting diamond, will offer low noise performance at about 2 K, a temperature provided by inexpensive close-cycle refrigerators, which provides another practical advantage of development and application of these devices. [1] P.K. Day, et. al, Nature, 425, 817, 2003. [2] J. Wei, et al, Nature Nanotech., 3, 496, 2008. [3] A. Kardakova, et al, Phys. Rev. B, 93, 064506, 2016. [4] P. Santhanam and D. Prober, Phys. Rev. B, 29, 3733, 1984 [5] A. Kardakova, et al, Appl. Phys. Lett, vol. 103, p. 252602, 2013. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1173 | |||
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| Author | Smirnov, K. V.; Vakhtomin, Yu. B.; Divochiy, A. V.; Ozhegov, R. V.; Pentin, I. V.; Gol'tsman, G. N. | ||||
| Title | Infrared and terahertz detectors on basis of superconducting nanostructures | Type | Conference Article | ||
| Year | 2010 | Publication | Microwave and Telecom. Technol. (CriMiCo), 20th Int. Crimean Conf. | Abbreviated Journal | |
| Volume | Issue | Pages | 823-824 | ||
| Keywords | SSPD, SNSPD, HEB | ||||
| Abstract | Results of development of single-photon receiving systems of visible, infrared and terahertz range based on thin-film superconducting nanostructures are presented. The receiving systems are produced on the basis of superconducting nanostructures, which function by means of hot-electron phenomena. | ||||
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| Publisher | Place of Publication | Editor | IEEE | ||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ sasha @ smirnov2010infrared | Serial | 1025 | ||
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| Author | Goltsman, G. N.; Korneev, A. A.; Finkel, M. I.; Divochiy, A. V.; Florya, I. N.; Korneeva, Y. P.; Tarkhov, M. A.; Ryabchun, S. A.; Tretyakov, I. V.; Maslennikov, S. N.; Kaurova, N. S.; Chulkova, G. M.; Voronov, B. M. | ||||
| Title | Superconducting hot-electron bolometer as THz mixer, direct detector and IR single-photon counter | Type | Abstract | ||
| Year | 2010 | Publication | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves | Abbreviated Journal | |
| Volume | Issue | Pages | 1-1 | ||
| Keywords | SSPD, SNSPD, HEB | ||||
| Abstract | We present a new generation of superconducting single-photon detectors (SSPDs) and hot-electron superconducting sensors with record characteristic for many terahertz and optical applications. | ||||
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| ISSN | 2162-2027 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ sasha @ goltsman2010superconducting | Serial | 1028 | ||
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| Author | Смирнов, Константин Владимирович; Вахтомин, Юрий Борисович; Смирнов, Андрей Владимирович; Ожегов, Роман Викторович; Пентин, Иван Викторович; Дивочий, Александр Валерьевич; Сливинская, Елизавета Вячеславовна; Гольцман, Григорий Наумович | ||||
| Title | Приемники терагерцового и инфракрасного диапазонов, основанные на тонкопленочных сверхпроводниковых наноструктурах | Type | Journal Article | ||
| Year | 2010 | Publication | Вестник НГУ. Серия: Физика | Abbreviated Journal | Вестник НГУ. Серия: Физика |
| Volume | 5 | Issue | 4 | Pages | |
| Keywords | HEB, SSPD, SNSPD | ||||
| Abstract | В работе представлены результаты разработки и создания чувствительных и ультрабыстрых приемников, основанных на тонкопленочных сверхпроводниковых наноструктурах: болометрах на эффекте электронного разогрева (HEB – hot-electron bolometer) и детекторах одиночных фотонов видимого и инфракрасного диапазонов волн (SSPD – superconducting singe-photon detector). Представлены основные принципы работы сверхпроводниковых устройств, технология создания и конструкционные особенности приемников, их основные типы и характеристики. Достигнутые рекордные значения параметров приемных систем позволяют использовать созданные приборы при решении различных научно-исследовательских задач в ближнем, среднем и дальнем ИК диапазонах волн. This work presents the results of the development and fabrication of sensitive and ultrafast detectorsbased on thin film superconducting nanostructures: hot-electron bolometers (HEBs) and visible and infrared superconducting singe photon detectors (SSPDs). The main operational principles of the superconducting devices are presentedas well as the technology of fabrication of the detectors and their main types and parameters. The achieved record parameters of the detectors allow application of the fabricated devices to solution of various research problems in the near, middle and far IR ranges. |
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| Publisher | Новосибирский государственный университет | Place of Publication | Editor | ||
| Language | Russian | Summary Language | Original Title | ||
| Series Editor | Series Title | Физика | Abbreviated Series Title | ||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1818-7994 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | УДК 538.9 | Approved | no | ||
| Call Number | RPLAB @ sasha @ смирнов2010приемники | Serial | 1033 | ||
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| Author | Skalare, A.; McGrath, William R.; Echternach, P. M.; Leduc, H. G.; Siddiqi, I.; Verevkin, A.; Prober, D. E. | ||||
| Title | Aluminum hot-electron bolometer mixers at submillimeter wavelengths | Type | Journal Article | ||
| Year | 2001 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
| Volume | 11 | Issue | 1 | Pages | 641-644 |
| Keywords | Al HEB mixer, contacts, interface, in situ, in-situ, Aluminium HEB mixer | ||||
| Abstract | Diffusion-cooled aluminum hot-electron bolometer (HEB) mixers are of interest for low-noise high resolution THz-frequency spectroscopy within astrophysics. Al HEB mixers offer operation with an order of magnitude less local oscillator power, higher intermediate frequency bandwidth and potentially lower noise than competing devices made from other materials. We report on mixer experiments at 618 GHz with devices fabricated from films with sheet resistances in the range from about 55 Ω down to about 9 Ω per square. Intermediate frequency bandwidths of up to 3 GHz were measured (1 μm long device), with absorbed local oscillator power levels of 0.5 to 6 nW and mixer conversion up to -21.5 dB. High input coupling efficiency implies that the electrons in the device are able to thermalize before escaping from the device. It was found that the long coherence length complicates mixer operations due to the proximity of the contact pads. Also, saturation at the IF frequency may be a concern for this type of device, and warrants further studies. | ||||
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| ISSN | 1051-8223 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | ref919426b | Serial | 1061 | ||
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| Author | Angeluts, A. A.; Bezotosnyi, V. V.; Cheshev, E. A.; Goltsman, G. N.; Finkel, M. I.; Seliverstov, S. V.; Evdokimov, M. N.; Gorbunkov, M. V.; Kitaeva, G. Kh.; Koromyslov, A. L.; Kostryukov, P. V.; Krivonos, M. S.; Lobanov, Yu. V.; Shkurinov, A. P.; Sarkisov, S. Yu.; Tunkin, V. G. | ||||
| Title | Compact 1.64 THz source based on a dual-wavelength diode end-pumped Nd:YLF laser with a nearly semiconfocal cavity | Type | Journal Article | ||
| Year | 2014 | Publication | Laser Phys. Lett. | Abbreviated Journal | |
| Volume | 11 | Issue | 1 | Pages | 015004 (1 to 4) |
| Keywords | HEB applications, HEB detector applications, short THz pulses detection | ||||
| Abstract | We describe a compact dual-wavelength (1.047 and 1.053 μm) diode end-pumped Q-switched Nd:YLE laser source which has a number of applications in demand. In order to achieve its dual-wavelength operation it is suggested for the first time to use essentially nonmonotonous dependences of the threshold pump powers at these wavelengths on the cavity length in the region of the cavity semiconfocal configuration under a radius of the pump beam smaller than the radius of the zero Gaussian mode. Here we demonstrate one of the most interesting applications for this laser: difference frequency generation in a GaSe crystal at a frequency of 1.64 THz. A superconducting hot-electron bolometer is used to detect the THz power generated and to measure its pulse characteristics. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1076 | |||
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| Author | Smirnov, A. V.; Baryshev, A. M.; de Bernardis, P.; Vdovin, V. F.; Gol'tsman, G. N.; Kardashev, N. S.; Kuz'min, L. S.; Koshelets, V. P.; Vystavkin, A. N.; Lobanov, Yu. V.; Ryabchun, S. A.; Finkel, M. I.; Khokhlov, D. R. | ||||
| Title | The current stage of development of the receiving complex of the millimetron space observatory | Type | Journal Article | ||
| Year | 2012 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
| Volume | 54 | Issue | 8 | Pages | 557-568 |
| Keywords | Millimetron space observatory, HEB applications | ||||
| Abstract | We present an overview of the state of the onboard receiving complex of the Millimetron space observatory in the development phase of its preliminary design. The basic parameters of the onboard equipment planned to create and required for astrophysical observations are considered. A review of coherent and incoherent detectors, which are central to each receiver of the observatory, is given. Their characteristics and limiting parameters feasible at the present level of technology are reported. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1079 | |||
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| Author | Benz, A. O.; Bruderer, S.; van Dishoeck, E. F.; Stäuber, P.; Wampfler, S. F.; Melchior, M.; Dedes, C.; Wyrowski, F.; Doty, S. D.; van der Tak, F.; Bächtold, W.; Csillaghy, A.; Megej, A.; Monstein, C.; Soldati, M.; Bachiller, R.; Baudry, A.; 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.; Dieleman, P.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Giannini, T.; Goicoechea, J. R.; de Graauw, Th.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Jellema, W.; Johnstone, D.; Jørgensen, J. K.; Kristensen, L. E.; Larsson, B.; Lis, D.; Liseau, R.; Marseille, M.; McCoey, C.; Melnick, G.; Neufeld, D.; Nisini, B.; Olberg, M.; Ossenkopf, V.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Schieder, R.; Shipman, R.; Stutzki, J.; Tafalla, M.; Tielens, A. G. G. M.; van Kempen, T. A.; Visser, R.; Yıldız, U. A. | ||||
| Title | Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system | Type | Journal Article | ||
| Year | 2010 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 521 | Issue | Pages | L35 (1 to 5) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Context. Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays. Aims. We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation. Methods. W3 IRS5 was observed by HIFI on the Herschel Space Observatory with deep integration (2500 s) in 8 spectral regions. Results. The target lines including CH, NH, H3O+, and the new molecules SH+, H2O+, and OH+ are detected. The H2O+ and OH+ J = 1–0 lines are found mostly in absorption, but also appear to exhibit weak emission (P-Cyg-like). Emission requires high density, thus originates most likely near the protostar. This is corroborated by the absence of line shifts relative to the young stellar object (YSO). In addition, H2O+ and OH+ also contain strong absorption components at a velocity shifted relative to W3 IRS5, which are attributed to foreground clouds. Conclusions. The molecular column densities derived from observations correlate well with the predictions of a model that assumes the main emission region is in outflow walls, heated and irradiated by protostellar UV radiation. |
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| Notes | Approved | no | |||
| Call Number | Serial | 1082 | |||
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| Author | Bujarrabal, V.; Alcolea, J.; Soria-Ruiz, R.; Planesas, P.; Teyssier, D.; Marston, A. P.; Cernicharo, J.; Decin, L.; Dominik, C.; Justtanont, K.; de Koter, A.; Melnick, G.; Menten, K. M.; Neufeld, D. A.; Olofsson, H.; Schmidt, M.; Schöier, F. L.; Szczerba, R.; Waters, L. B. F. M.; Quintana-Lacaci, G.; Güsten, R.; Gallego, J. D.; Díez-González, M. C.; Barcia, A.; López-Fernández, I.; Wildeman, K.; Tielens, A. G. G. M.; Jacobs, K. | ||||
| Title | Herschel/HIFI observations of high-J CO transitions in the protoplanetary nebula CRL 618 | Type | Journal Article | ||
| Year | 2010 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 521 | Issue | Pages | L3 (1 to 5) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Aims. We aim to study the physical conditions, particularly the excitation state, of the intermediate-temperature gas components in the protoplanetary nebula CRL 618. These components are particularly important for understanding the evolution of the nebula. Methods. We performed Herschel/HIFI observations of several CO lines in the far-infrared/sub-mm in the protoplanetary nebula CRL 618. The high spectral resolution provided by HIFI allows measurement of the line profiles. Since the dynamics and structure of the nebula is well known from mm-wave interferometric maps, it is possible to identify the contributions of the different nebular components (fast bipolar outflows, double shells, compact slow shell) to the line profiles. The observation of these relatively high-energy transitions allows an accurate study of the excitation conditions in these components, particularly in the warm ones, which cannot be properly studied from the low-energy lines. Results. The 12CO J = 16–15, 10–9, and 6–5 lines are easily detected in this source. Both 13CO J = 10–9 and 6–5 are also detected. Wide profiles showing spectacular line wings have been found, particularly in 12CO J = 16–15. Other lines observed simultaneously with CO are also shown. Our analysis of the CO high-J transitions, when compared with the existing models, confirms the very low expansion velocity of the central, dense component, which probably indicates that the shells ejected during the last AGB phases were driven by radiation pressure under a regime of maximum transfer of momentum. No contribution of the diffuse halo found from mm-wave data is identified in our spectra, because of its low temperature. We find that the fast bipolar outflow is quite hot, much hotter than previously estimated; for instance, gas flowing at 100 km s-1 must have a temperature higher than ~200 K. Probably, this very fast outflow, with a kinematic age <100 yr, has been accelerated by a shock and has not yet cooled down. The double empty shell found from mm-wave mapping must also be relatively hot, in agreement with the previous estimate. |
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| Call Number | Serial | 1084 | |||
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| Author | Cavalié, T.; Feuchtgruber, H.; Lellouch, E.; de Val-Borro, M.; Jarchow, C.; Moreno, R.; Hartogh, P.; Orton, G.; Greathouse, T. K.; Billebaud, F.; Dobrijevic, M.; Lara, L. M.; González, A.; Sagawa, H. | ||||
| Title | Spatial distribution of water in the stratosphere of Jupiter from Herschel HIFI and PACS observations | Type | Journal Article | ||
| Year | 2013 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 553 | Issue | Pages | A21 (1 to 16) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Context. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the Shoemaker-Levy 9 (SL9) comet impacts in July 1994, but a direct proof was missing. Only a very sensitive instrument observing with high spectral/spatial resolution can help to solve this problem. This is the case of the Herschel Space Observatory, which is the first telescope capable of mapping water in Jupiter's stratosphere. Aims. We observed the spatial distribution of the water emission in Jupiter's stratosphere with the Heterodyne Instrument for the Far Infrared (HIFI) and the Photodetector Array Camera and Spectrometer (PACS) onboard Herschel to constrain its origin. In parallel, we monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. Methods. We obtained a 25-point map of the 1669.9 GHz water line with HIFI in July 2010 and several maps with PACS in October 2009 and December 2010. The 2010 PACS map is a 400-point raster of the water 66.4 μm emission. Additionally, we mapped the methane ν4 band emission to constrain the stratospheric temperature in Jupiter in the same periods with the IRTF. Results. Water is found to be restricted to pressures lower than 2 mbar. Its column density decreases by a factor of 2–3 between southern and northern latitudes, consistently between the HIFI and the PACS 66.4 μm maps. We infer that an emission maximum seen around 15 °S is caused by a warm stratospheric belt detected in the IRTF data. Conclusions. Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical distributions of water in Jupiter's stratosphere, we rule out interplanetary dust particles as its main source. Furthermore, we demonstrate that Jupiter's stratospheric water was delivered by the SL9 comet and that more than 95% of the observed water comes from the comet according to our models. |
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| Author | Chavarr'ıa, L.; Herpin, F.; Jacq, T.; Braine, J.; Bontemps, S.; Baudry, A.; Marseille, M.; van der Tak, F.; Pietropaoli, B.; Wyrowski, F.; Shipman, R.; Frieswijk, W.; van Dishoeck, E. F.; Cernicharo, J.; Bachiller, R.; Benedettini, M.; Benz, A. O.; Bergin, E.; Bjerkeli, P.; Blake, G. A.; Bruderer, S.; Caselli, P.; Codella, C.; Daniel, F.; di Giorgio, A. M.; Dominik, C.; Doty, S. D.; Encrenaz, P.; Fich, M.; Fuente, A.; Giannini, T.; Goicoechea, J. R.; de Graauw, T.; Hartogh, P.; Helmich, F.; Herczeg, G. J.; Hogerheijde, M. R.; Johnstone, D.; Jørgensen, J. K.; Kristensen, L. E.; Larsson, B.; Lis, D.; Liseau, R.; McCoey, C.; Melnick, G.; Nisini, B.; Olberg, M.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-Garc'ıa, J.; Saraceno, P.; Stutzki, J.; Szczerba, R.; Tafalla, M.; Tielens, A.; van Kempen, T. A.; Visser, R.; Wampfler, S. F.; Willem, J.; Yıldız, U. A. | ||||
| Title | Water in massive star-forming regions: HIFI observations of W3 IRS5 | Type | Journal Article | ||
| Year | 2010 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 521 | Issue | Pages | L37 (1 to 5) | |
| Keywords | HEB mixer applications, HIFI, Herschel, stars: formation, stars: massive, ISM: molecules, ISM: abundances, dust, extinction, radio lines: ISM | ||||
| Abstract | We present Herschel observations of the water molecule in the massive star-forming region W3 IRS5. The o-H217O 110-101, p-H218O 111-000, p-H2O 202-111, p-H2O 111-000, o-H2O 221-212, and o-H2O 212-101 lines, covering a frequency range from 552 up to 1669 GHz, have been detected at high spectral resolution with HIFI. The water lines in W3 IRS5 show well-defined high-velocity wings that indicate a clear contribution by outflows. Moreover, the systematically blue-shifted absorption in the H2O lines suggests expansion, presumably driven by the outflow. No infall signatures are detected. The p-H2O 111-000 and o-H2O 212-101 lines show absorption from the cold material (T ~ 10 K) in which the high-mass protostellar envelope is embedded. One-dimensional radiative transfer models are used to estimate water abundances and to further study the kinematics of the region. We show that the emission in the rare isotopologues comes directly from the inner parts of the envelope (T â‰<b3> 100 K) where water ices in the dust mantles evaporate and the gas-phase abundance increases. The resulting jump in the water abundance (with a constant inner abundance of 10-4) is needed to reproduce the o-H217O 110-101 and p-H218O 111-000 spectra in our models. We estimate water abundances of 10-8 to 10-9 in the outer parts of the envelope (T â‰<b2> 100 K). The possibility of two protostellar objects contributing to the emission is discussed. | ||||
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| Call Number | Chav13HEBapplHIFIb | Serial | 1086 | ||
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