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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. doi  openurl
  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 (up) 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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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1084  
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Author Dauler, E. A.; Kerman, A. J.; Robinson, B. S.; Yang, J. K. W.; Voronov, B. M.; Gol’tsman, G. N.; Berggren, K. K. url  doi
openurl 
  Title Achieving high counting rates in superconducting nanowire single-photon detectors Type Conference Article
  Year 2006 Publication CLEO/QELS Abbreviated Journal CLEO/QELS  
  Volume Issue Pages (up) JTuD3 (1 to 2)  
  Keywords SSPD; SNSPD; Detectors; Photodetectors; Quantum optics; Quantum detectors; Photon counting; Photons; Pulse shaping; Quantum communications; Single photon detectors; Superconductors  
  Abstract Kinetic inductance is determined to be the primary limitation to the counting rate of superconducting nanowire single-photon counters. Approaches for overcoming this limitation will be discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Optical Society of America Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies  
  Notes Approved no  
  Call Number Serial 1451  
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Author Hübers, H.-W.; Semenov, A.; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Smirnov, K.; Gol’tsman, G.; Voronov, B. url  openurl
  Title Terahertz Heterodyn Receiver with a hot-electron bolometer mixer Type Conference Article
  Year 2002 Publication Far-IR, Sub-mm & MM Detector Technology Workshop Abbreviated Journal Far-IR, Sub-mm & MM Detector Technology Workshop  
  Volume Issue Pages (up) 3-24  
  Keywords NbN HEB mixers  
  Abstract During the past decade major advances have been made regarding low noise mixers for terahertz (THz) heterodyne receivers. State of the art hot-electron-bolometer (HEB) mixers have noise temperatures close to the quantum limit and require less than a µW power from the local oscillator (LO). The technology is now at a point where the performance of a practical receiver employing such mixer, rather than the figures of merit of the mixer itself, are of major concern. We have incorporated a phonon-cooled NbN HEB mixer in a 2.5 THz heterodyne receiver and investigated the performance of the receiver. This yields important information for the development of heterodyne receivers such as GREAT (German receiver for astronomy at THz frequencies aboard SOFIA) [1] and TELIS (Terahertz limb sounder), a balloon borne heterodyne receiver for atmospheric research [2]. Both are currently under development at DLR.  
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  Publisher NASA Place of Publication Editor Wolf, U.; Farhoomand, J.; McCreight, C.R.  
  Language Summary Language Original Title  
  Series Editor Series Title NASA CP Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Volume: 211408 Approved no  
  Call Number Serial 1537  
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Author Semenov, A.; Hübers, H.-W.; Engel, A.; Gol’tsman, G. url  openurl
  Title Superconducting quantum detector for far infrared astronomy Type Conference Article
  Year 2002 Publication Far-IR, Sub-mm & MM Detector Technology Workshop Abbreviated Journal Far-IR, Sub-mm & MM Detector Technology Workshop  
  Volume Issue Pages (up) 3-49  
  Keywords SQD  
  Abstract We present the concept of the superconducting quantum detector for astronomy. Response to a single absorbed photon appears due to successive formation of a normal spot and phase-slip-centres in a narrow strip carrying sub-critical supercurrent. The detector simultaneously has a moderate energy resolution and a variable cut-off wavelength depending on both the material used and operation conditions. We simulated performance of the background-limited direct detector having the 100-micrometer cut-off wavelength. Low dark count rate will allow to realise 10-21 W Hz-1/2 noise equivalent power at 4 K background radiation. The detection mechanism provides a moderate 1/20 energy resolution at 50-micrometer wavelength.  
  Address  
  Corporate Author Thesis  
  Publisher NASA Place of Publication Editor Wolf, J.; Farhoomand, J.; McCreight, C.R.  
  Language Summary Language Original Title  
  Series Editor Series Title NASA CP Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Volume: 211408 Approved no  
  Call Number Serial 1538  
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Author Goltsman, Gregory url  openurl
  Title Superconducting thin film nanostructures as terahertz and infrared heterodyne and direct detectors Type Conference Article
  Year 2017 Publication 16th ISEC Abbreviated Journal 16th ISEC  
  Volume Issue Pages (up) Th-I-QTE-03 (1 to 3)  
  Keywords waveguide SSPD, SNSPD  
  Abstract We present our recent achievements in the development of superconducting nanowire single-photon detectors (SNSPDs) integrated with optical waveguides on a chip. We demonstrate both single-photon counting with up to 90% on-chipquantum-efficiency (OCDE), and the heterodyne mixing with a close to the quantum limit sensitivity at the telecommunication wavelength using single device.  
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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 ISBN Medium  
  Area Expedition Conference IEEE/CSC & ESAS Superconductivity News Forum  
  Notes Approved no  
  Call Number Serial 1745  
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