Home << 1 2 3 4 5 6 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Zinoni, C.; Alloing, B.; Li, L. H.; Marsili, F.; Fiore, A.; Lunghi, L.; Gerardino, A.; Vakhtomin, Y. B.; Smirnov, K. V.; Gol’tsman, G. N.
Title Erratum: “Single photon experiments at telecom wavelengths using nanowire superconducting detectors” [Appl. Phys. Lett. 91, 031106 (2007)] Type Journal Article
Year 2010 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume (up) 96 Issue 8 Pages 089901
Keywords SSPD, SNSPD, erratum
Abstract A calculation error was made in the original publication of this letter. The error was in the calculation of the noise equivalent power (NEP) values for the avalanche photodiode detector (APD) and the superconducting single photon detector (SSPD), the incorrect values were plotted on the right axis in Fig. 1(b). The correct NEP values were calculated with the same equation reported in the original letter and the revised Fig. 1(b) is shown below. The other conclusions of the paper remain unaltered.
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 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1395
Permanent link to this record
 
 
Author Terai, Hirotaka; Miki, Shigehito; Yamashita, Taro; Makise, Kazumasa; Wang, Zhen
Title Demonstration of single-flux-quantum readout operation for superconducting single-photon detectors Type Journal Article
Year 2010 Publication Applied Physics Letters Abbreviated Journal Appl. Phys. Lett.
Volume (up) 97 Issue 11 Pages 3
Keywords SSPD
Abstract A readout circuit using superconducting single-flux-quantum (SFQ) circuits has been developed to realize an independently addressable array of superconducting single-photon detectors (SSPDs). We tested the SFQ readout circuits by connecting with SSPDs. The error rates of readout circuits were below 10–5 for input signal amplitude of greater than 18.2 μA. Detection efficiencies (DEs) for single-photon incidents were measured both with and without the connection of a readout circuit. The observed DEs traced almost the same curves regardless of the connection of the readout circuit, except that the SSPD is likely to latch by connecting the readout circuit.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 654
Permanent link to this record
 
 
Author Gaggero, A.; Nejad, S. Jahanmiri; Marsili, F.; Mattioli, F.; Leoni, R.; Bitauld, D.; Sahin, D.; Hamhuis, G. J.; Nötzel, R.; Sanjines, R.; Fiore, A.
Title Nanowire superconducting single-photon detectors on GaAs for integrated quantum photonic applications Type Journal Article
Year 2010 Publication Applied Physics Letters Abbreviated Journal Appl. Phys. Lett.
Volume (up) 97 Issue 15 Pages 3
Keywords SSPD
Abstract We demonstrate efficient nanowire superconducting single photon detectors (SSPDs) based on NbN thin films grown on GaAs. NbN films ranging from 3 to 5 nm in thickness have been deposited by dc magnetron sputtering on GaAs substrates at 350 °C. These films show superconducting properties comparable to similar films grown on sapphire and MgO. In order to demonstrate the potential for monolithic integration, SSPDs were fabricated and measured on GaAs/AlAs Bragg mirrors, showing a clear cavity enhancement, with a peak quantum efficiency of 18.3% at λ = 1300 nm and T = 4.2 K.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 681
Permanent link to this record
 
 
Author Mannino, Giovanni; Spinella, Corrado; Ruggeri, Rosa; La Magna, Antonino; Fisicaro, Giuseppe; Fazio, Enza; Neri, Fortunato; Privitera, Vittorio
Title Crystallization of implanted amorphous silicon during millisecond annealing by infrared laser irradiation Type Journal Article
Year 2010 Publication Applied Physics Letters Abbreviated Journal Appl. Phys. Lett.
Volume (up) 97 Issue 2 Pages 3
Keywords Annealing
Abstract We investigated the homogenous nucleation of crystalline grains in amorphous Si during transient temperature pulse of few milliseconds IR laser irradiation. The crystallized volume fraction is ~80%. Significant crystallization occurs in nonsteady regime because of the rapid temperature variation (106 °C/s). Our model combines the time evolution of the crystal grain population with the consumption of the amorphous volume due to the growth of grains. Thanks to the experimental approach based on a laser source to heat α-Si and the theoretical model we extended the description of the spontaneous crystallization up to 1323 K or 250 K above the temperature investigated by conventional annealing.
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 ISBN Medium
Area Expedition Conference
Notes Annealing Approved no
Call Number RPLAB @ gujma @ Serial 691
Permanent link to this record
 
 
Author Kataoka, T; Kajikawa, K.; Kitagawa, J.; Kadoya, Y; Takemura, Y.
Title Improved sensitivity of terahertz detection by GaAs photoconductive antennas excited at 1560 nm Type Journal Article
Year 2010 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume (up) 97 Issue Pages 201110 (1-3)
Keywords photoconductive antenna (PCA)
Abstract The terahertz detection by photoconductive antennas (PCAs) based on low-temperature grown (LTG) GaAs with 1.5 μm pulse excitation was revisited. We found that the detection efficiency can be improved by a factor of 10 (20 dB) by reducing the excitation spot size and the gap length of the PCA, maintaining the low noise feature of the PCA on LTG GaAs. As a result, the signal-to-noise ratio higher than 50 dB was obtained at a reasonable incident power of 9.5 mW, suggesting that the scheme is promising for the detection of terahertz waves in practical time domain systems.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 904
Permanent link to this record
 
 
Author Elvira, D.; Michon, A.; Fain, B.; Patriarche, G.; Beaudoin, G.; Robert-Philip, I.; Vachtomin, Y.; Divochiy, A. V.; Smirnov, K. V.; Gol’tsman, G. N.; Sagnes, I.; Beveratos, A.
Title Time-resolved spectroscopy of InAsP/InP(001) quantum dots emitting near 2 μm Type Journal Article
Year 2010 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume (up) 97 Issue 13 Pages 131907 (1 to 3)
Keywords SSPD, SNSPD, InAsP/InP quantum dots
Abstract By using superconducting single photon detectors, we perform time-resolved characterization of a small ensemble of InAsP/InP quantum dots grown by metal organic vapor phase epitaxy, emitting at wavelengths between 1.6 and 2.2 μm. We demonstrate that alloying phosphorus with InAs allows to shift the emission wavelength toward higher wavelengths, while keeping the high optical quality of these quantum dots at room temperature, with no decrease in their radiative lifetime. This work was partially supported by Russian Ministry of Science and Education: Federal State Program “Scientific and Educational Cadres of Innovative” state Contract Nos. 02.740.0228, 14.740.11.0343, 14.740.11.0269, and P931, and RFBR Project No. 09-02-12364.
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 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1238
Permanent link to this record
 
 
Author Maingault, L.; Tarkhov, M.; Florya, I.; Semenov, A.; Espiau de Lamaëstre, R.; Cavalier, P.; Gol’tsman, G.; Poizat, J.-P.; Villégier, J.-C.
Title Spectral dependency of superconducting single photon detectors Type Journal Article
Year 2010 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume (up) 107 Issue 11 Pages 116103 (1 to 3)
Keywords NbN SSPD, SNSPD
Abstract We investigate the effect of varying both incoming optical wavelength and width of NbN nanowires on the superconducting single photon detectors (SSPD) detection efficiency. The SSPD are current biased close to critical value and temperature fixed at 4.2 K, far from transition. The experimental results are found to verify with a good accuracy predictions based on the “hot spot model,” whose size scales with the absorbed photon energy. With larger optical power inducing multiphoton detection regime, the same scaling law remains valid, up to the three-photon regime. We demonstrate the validity of applying a limited number of measurements and using such a simple model to reasonably predict any SSPD behavior among a collection of nanowire device widths at different photon wavelengths. These results set the basis for designing efficient single photon detectors operating in the infrared (2–5 μm range).

This work was supported by European projects FP6 STREP “SINPHONIA” (Contract No. NMP4-CT-2005-16433) and IP “QAP” (Contract No. 15848).
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 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1392
Permanent link to this record
 
 
Author Annunziata, Anthony J.; Quaranta, Orlando; Santavicca, Daniel F.; Casaburi, Alessandro; Frunzio, Luigi; Ejrnaes, Mikkel; Rooks, Michael J.; Cristiano, Roberto; Pagano, Sergio; Frydman, Aviad; Prober, Daniel E.
Title Reset dynamics and latching in niobium superconducting nanowire single-photon detectors Type Journal Article
Year 2010 Publication J. Appl. Phys. Abbreviated Journal
Volume (up) 108 Issue 8 Pages 7
Keywords SNSPD
Abstract We study the reset dynamics of niobium (Nb) superconducting nanowire single-photon detectors (SNSPDs) using experimental measurements and numerical simulations. The numerical simulations of the detection dynamics agree well with experimental measurements, using independently determined parameters in the simulations. We find that if the photon-induced hotspot cools too slowly, the device will latch into a dc resistive state. To avoid latching, the time for the hotspot to cool must be short compared to the inductive time constant that governs the resetting of the current in the device after hotspot formation. From simulations of the energy relaxation process, we find that the hotspot cooling time is determined primarily by the temperature-dependent electron-phonon inelastic time. Latching prevents reset and precludes subsequent photon detection. Fast resetting to the superconducting state is, therefore, essential, and we demonstrate experimentally how this is achieved. We compare our results to studies of reset and latching in niobium nitride SNSPDs.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 649
Permanent link to this record
 
 
Author Братман, В.Л.; Литвак, А.Г.; Суворов, Е.В.
Title Освоение терагерцевого диапазона: источники и приложения Type Journal Article
Year 2010 Publication Успехи физических наук Abbreviated Journal Успехи физ. наук
Volume (up) 181 Issue 8 Pages 867–874
Keywords HEB
Abstract
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 674
Permanent link to this record
 
 
Author Seki, T.; Shibata, H.; Takesue, H.; Tokura, Y.; Imoto, N.
Title Comparison of timing jitter between NbN superconducting single-photon detector and avalanche photodiode Type Journal Article
Year 2010 Publication Phys. C Abbreviated Journal Phys. C
Volume (up) 470 Issue 20 Pages 1534-1537
Keywords SSPD; APD; jitter
Abstract We report the pulse-to-pulse timing jitter measurement of a niobium nitride (NbN) superconducting single-photon detector (SSPD) and an InGaAs avalanche photodiode (APD) at 1550-nm wavelength. A direct comparison of their timing jitter was performed by using the same experimental configuration to measure both detectors. The measured jitter of the SSPD and the APD are 75 and 84 ps at full-width at half-maximum (FWHM), and 138 and 384 ps at full-width at tenth-maximum (FWTM), respectively. The jitter of the SSPD remains small at FWTM while that of APD is wide. We also estimated the transmission distances and secure key generation rates for fiber-based quantum key distribution (QKD) which uses these detectors. The estimated transmission distances of the APD are 86 km and 107 km with respect to 1 ns and 100 ps time windows, respectively, and those of the SSPD are 125 km and 172 km with respect to 1 ns and 100 ps time windows, respectively. This estimation indicates the SSPDЃfs advantages for QKD compared to the APD.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ akorneev @ Serial 613
Permanent link to this record
 
 
Author Poglitsch, A.; Waelkens, C.; Geis, N.; Feuchtgruber, H.; Vandenbussche, B.; Rodriguez, L.; Krause, O.; Renotte, E.; van Hoof, C.; Saraceno, P.; Cepa, J.; Kerschbaum, F.; Agnèse, P.; Ali, B.; Altieri, B.; Andreani, P.; Augueres, J.-L.; Balog, Z.; Barl, L.; Bauer, O. H.; Belbachir, N.; Benedettini, M.; Billot, N.; Boulade, O.; Bischof, H.; Blommaert, J.; Callut, E.; Cara, C.; Cerulli, R.; Cesarsky, D.; Contursi, A.; Creten, Y.; De Meester, W.; Doublier, V.; Doumayrou, E.; Duband, L.; Exter, K.; Genzel, R.; Gillis, J.-M.; Grözinger, U.; Henning, T.; Herreros, J.; Huygen, R.; Inguscio, M.; Jakob, G.; Jamar, C.; Jean, C.; de Jong, J.; Katterloher, R.; Kiss, C.; Klaas, U.; Lemke, D.; Lutz, D.; Madden, S.; Marquet, B.; Martignac, J.; Mazy, A.; Merken, P.; Montfort, F.; Morbidelli, L.; Müller, T.; Nielbock, M.; Okumura, K.; Orfei, R.; Ottensamer, R.; Pezzuto, S.; Popesso, P.; Putzeys, J.; Regibo, S.; Reveret, V.; Royer, P.; Sauvage, M.; Schreiber, J.; Stegmaier, J.; Schmitt, D.; Schubert, J.; Sturm, E.; Thiel, M.; Tofani, G.; Vavrek, R.; Wetzstein, M.; Wieprecht, E.; Wiezorrek, E.
Title The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal A&A
Volume (up) 518 Issue Pages 12
Keywords PACS
Abstract The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments on ESA's far infrared and submillimetre observatory. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16×25 pixels, each, and two filled silicon bolometer arrays with 16×32 and 32×64 pixels, respectively, to perform integral-field spectroscopy and imaging photometry in the 60-210 μm wavelength regime. In photometry mode, it simultaneously images two bands, 60-85 μm or 85-125 μm and 125-210 μm, over a field of view of ~1.75'× 3.5', with close to Nyquist beam sampling in each band. In spectroscopy mode, it images a field of 47” × 47”, resolved into 5×5 pixels, with an instantaneous spectral coverage of ~1500 km s-1 and a spectral resolution of ~175 km s-1. We summarise the design of the instrument, describe observing modes, calibration, and data analysis methods, and present our current assessment of the in-orbit performance of the instrument based on the performance verification tests. PACS is fully operational, and the achieved performance is close to or better than the pre-launch predictions.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 694
Permanent link to this record
 
 
Author Griffin, M. J.; Abergel, A.; Abreu, A.; Ade, P. A. R.; André, P.; Augueres, J.-L.; Babbedge, T.; Bae, Y.; Baillie, T.; Baluteau, J.-P.; Barlow, M. J.; Bendo, G.; Benielli, D.; Bock, J. J.; Bonhomme, P.; Brisbin, D.; Brockley-Blatt, C.; Caldwell, M.; Cara, C.; Castro-Rodriguez, N.; Cerulli, R.; Chanial, P.; Chen, S.; Clark, E.; Clements, D. L.; Clerc, L.; Coker, J.; Communal, D.; Conversi, L.; Cox, P.; Crumb, D.; Cunningham, C.; Daly, F.; Davis, G. R.; de Antoni, P.; Delderfield, J.; Devin, N.; di Giorgio, A.; Didschuns, I.; Dohlen, K.; Donati, M.; Dowell, A.; Dowell, C. D.; Duband, L.; Dumaye, L.; Emery, R. J.; Ferlet, M.; Ferrand, D.; Fontignie, J.; Fox, M.; Franceschini, A.; Frerking, M.; Fulton, T.; Garcia, J.; Gastaud, R.; Gear, W. K.; Glenn, J.; Goizel, A.; Griffin, D. K.; Grundy, T.; Guest, S.; Guillemet, L.; Hargrave, P. C.; Harwit, M.; Hastings, P.; Hatziminaoglou, E.; Herman, M.; Hinde, B.; Hristov, V.; Huang, M.; Imhof, P.; Isaak, K. J.; Israelsson, U.; Ivison, R. J.; Jennings, D.; Kiernan, B.; King, K. J.; Lange, A. E.; Latter, W.; Laurent, G.; Laurent, P.; Leeks, S. J.; Lellouch, E.; Levenson, L.; Li, B.; Li, J.; Lilienthal, J.; Lim, T.; Liu, S. J.; Lu, N.; Madden, S.; Mainetti, G.; Marliani, P.; McKay, D.; Mercier, K.; Molinari, S.; Morris, H.; Moseley, H.; Mulder, J.; Mur, M.; Naylor, D. A.; Nguyen, H.; O'Halloran, B.; Oliver, S.; Olofsson, G.; Olofsson, H.-G.; Orfei, R.; Page, M. J.; Pain, I.; Panuzzo, P.; Papageorgiou, A.; Parks, G.; Parr-Burman, P.; Pearce, A.; Pearson, C.; Pérez-Fournon, I.; Pinsard, F.; Pisano, G.; Podosek, J.; Pohlen, M.; Polehampton, E. T.; Pouliquen, D.; Rigopoulou, D.; Rizzo, D.; Roseboom, I. G.; Roussel, H.; Rowan-Robinson, M.; Rownd, B.; Saraceno, P.; Sauvage, M.; Savage, R.; Savini, G.; Sawyer, E.; Scharmberg, C.; Schmitt, D.; Schneider, N.; Schulz, B.; Schwartz, A.; Shafer, R.; Shupe, D. L.; Sibthorpe, B.; Sidher, S.; Smith, A.; Smith, A. J.; Smith, D.; Spencer, L.; Stobie, B.; Sudiwala, R.; Sukhatme, K.; Surace, C.; Stevens, J. A.; Swinyard, B. M.; Trichas, M.; Tourette, T.; Triou, H.; Tseng, S.; Tucker, C.; Turner, A.; Vaccari, M.; Valtchanov, I.; Vigroux, L.; Virique, E.; Voellmer, G.; Walker, H.; Ward, R.; Waskett, T.; Weilert, M.; Wesson, R.; White, G. J.; Whitehouse, N.; Wilson, C. D.; Winter, B.; Woodcraft, A. L.; Wright, G. S.; Xu, C. K.; Zavagno, A.; Zemcov, M.; Zhang, L.; Zonca, E.
Title The Herschel-SPIRE instrument and its in-flight performance Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal A&A
Volume (up) 518 Issue Pages 7
Keywords SPIRE
Abstract The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 μm, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 μm (447-1550 GHz). The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 0.3 K. The photometer has a field of view of 4Â´× 8´, observed simultaneously in the three spectral bands. Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired. The spectrometer has an approximately circular field of view with a diameter of 2.6´. The spectral resolution can be adjusted between 1.2 and 25 GHz by changing the stroke length of the FTS scan mirror. Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data. For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view. The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling. Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products. The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 1.5-2.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 695
Permanent link to this record
 
 
Author Hartogh, P.; Crovisier, J.; de Val-Borro, M.; Bockelée-Morvan, D.; Biver, N.; Lis, D. C.; Moreno, R.; Jarchow, C.; Rengel, M.; Emprechtinger, M.; Szutowicz, S.; Banaszkiewicz, M.; Bensch, F.; Blecka, M. I.; Cavalié, T.; Encrenaz, T.; Jehin, E.; Küppers, M.; Lara, L.-M.; Lellouch, E.; Swinyard, B. M.; Vandenbussche, B.; Bergin, E. A.; Blake, G. A.; Blommaert, J. A. D. L.; Cernicharo, J.; Decin, L.; Encrenaz, P.; de Graauw, T.; Hutsemekers, D.; Kidger, M.; Manfroid, J.; Medvedev, A. S.; Naylor, D. A.; Schieder, R.; Thomas, N.; Waelkens, C.; Roelfsema, P. R.; Dieleman, P.; Güsten, R.; Klein, T.; Kasemann, C.; Caris, M.; Olberg, M.; Benz, A. O.
Title HIFI observations of water in the atmosphere of comet C/2008 Q3 (Garradd) Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume (up) 518 Issue Pages L150 (1 to 5)
Keywords HEB mixer applications, HIFI, Herschel, comets: individual: C/2008 Q3 / radio lines: general / submillimeter: general / techniques: spectroscopic
Abstract High-resolution far-infrared and sub-millimetre spectroscopy of water lines is an important tool to understand the physical and chemical properties of cometary atmospheres. We present observations of several rotational ortho- and para-water transitions in comet C/2008 Q3 (Garradd) performed with HIFI on Herschel. These observations have provided the first detection of the 212–101 (1669 GHz) ortho and 111–000 (1113 GHz) para transitions of water in a cometary spectrum. In addition, the ground-state transition 110–101 at 557 GHz is detected and mapped. By detecting several water lines quasi-simultaneously and mapping their emission we can constrain the excitation parameters in the coma. Synthetic line profiles are computed using excitation models which include excitation by collisions, solar infrared radiation, and radiation trapping. We obtain the gas kinetic temperature, constrain the electron density profile, and estimate the coma expansion velocity by analyzing the map and line shapes. We derive water production rates of 1.7–2.8 × 1028 s-1 over the range rh = 1.83–1.85 AU.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1088
Permanent link to this record
 
 
Author Bruderer, S.; Benz, A. O.; van Dishoeck, E. F.; Melchior, M.; Doty, S. D.; van der Tak, F.; Stäuber, P.; Wampfler, S. F.; Dedes, C.; Yıldız, U. A.; Pagani, L.; Giannini, T.; de Graauw, Th.; Whyborn, N.; Teyssier, D.; Jellema, W.; Shipman, R.; Schieder, R.; Honingh, N.; Caux, E.; Bächtold, W.; Csillaghy, A.; Monstein, C.; 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.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Goicoechea, J. R.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; 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.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Shipman, R.; Tafalla, M.; van Kempen, T. A.; Visser, R.; Wyrowski, F.
Title Herschel/HIFI detections of hydrides towards AFGL 2591. Envelope emission versus tenuous cloud absorption Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume (up) 521 Issue Pages L44 (1 to 7)
Keywords HEB mixer applications, HIFI, Herschel
Abstract The Heterodyne Instrument for the Far Infrared (HIFI) onboard the Herschel Space Observatory allows the first observations of light diatomic molecules at high spectral resolution and in multiple transitions. Here, we report deep integrations using HIFI in different lines of hydrides towards the high-mass star forming region AFGL 2591. Detected are CH, CH+, NH, OH+, H2O+, while NH+ and SH+ have not been detected. All molecules except for CH and CH+ are seen in absorption with low excitation temperatures and at velocities different from the systemic velocity of the protostellar envelope. Surprisingly, the CH(JF,P = 3/22,- – 1/21,+ ) and CH+(J = 1–0, J = 2–1) lines are detected in emission at the systemic velocity. We can assign the absorption features to a foreground cloud and an outflow lobe, while the CH and CH+ emission stems from the envelope. The observed abundance and excitation of CH and CH+ can be explained in the scenario of FUV irradiated outflow walls, where a cavity etched out by the outflow allows protostellar FUV photons to irradiate and heat the envelope at larger distances driving the chemical reactions that produce these molecules.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1083
Permanent link to this record
 
 
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 (up) 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.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1082
Permanent link to this record