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Your search keyword '"Gozzini, S."' showing total 16 results
Start Over Author "Gozzini, S." Publisher elsevier b.v.
16 results on '"Gozzini, S."'

4. Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes

Author

Aleksić, J., Ansoldi, S., Biasuzzi, B., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Persic, M., Prada Moroni, P. G., Prandini, E., Preziuso, S., Puljak, I., Reinthal, R., Biland, A., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Rügamer, S., Saggion, A., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Blanch, O., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Bonnefoy, S., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Bonnoli, G., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Uellenbeck, M., Vogler, P., Wagner, R. M., Zanin, R., Borracci, F., Horns, D., Martín, J., Meyer, M., MAGIC Collaboration, Bretz, T., Carmona, E., Carosi, A., Colin, P., Antonelli, L. A., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., de Oña Wilhelmi, E., Antoranz, P., Delgado Mendez, C., Doert, M., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fonseca, M. V., Font, L., Babic, A., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Godinović, N., González Muñoz, A., Gozzini, S. R., Bangale, P., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Barrio, J. A., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Becerra González, J., López, M., López-Coto, R., López-Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Bednarek, W., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Bernardini, E., Nakajima, D., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Nowak, N., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., and Universitat de Barcelona

Subjects
Astrofísica, Nuclear and High Energy Physics, Very high energy gamma rays, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astrophysics, 01 natural sciences, Imaging atmospheric Cherenkov telescopes, Raigs gamma, Crab Nebula, MAGIC telescopes, Pulsar wind nebulae, Astronomy and Astrophysics, Space and Planetary Science, 0103 physical sciences, ddc:530, MAGIC (telescope), 010303 astronomy & astrophysics, Pulsars, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Nebula, ta115, Telescopis, 010308 nuclear & particles physics, Gamma rays, Gamma ray, Light curve, Púlsars, Wavelength, Spectral energy distribution, Pulsar Wind Nebulae, Imaging Atmospheric Cherenkov Telescopes, very high energy gamma rays, Astrophysics - High Energy Astrophysical Phenomena, Telescopes
Abstract

The MAGIC stereoscopic system collected 69 hours of Crab Nebula data between October 2009 and April 2011. Analysis of this data sample using the latest improvements in the MAGIC stereoscopic software provided an unprecedented precision of spectral and night-by-night light curve determination at gamma rays. We derived a differential spectrum with a single instrument from 50 GeV up to almost 30 TeV with 5 bins per energy decade. At low energies, MAGIC results, combined with Fermi-LAT data, show a flat and broad Inverse Compton peak. The overall fit to the data between 1 GeV and 30 TeV is not well described by a log-parabola function. We find that a modified log-parabola function with an exponent of 2.5 instead of 2 provides a good description of the data ($\chi^2=35/26$). Using systematic uncertainties of red the MAGIC and Fermi-LAT measurements we determine the position of the Inverse Compton peak to be at (53 $\pm$ 3stat + 31syst -13syst) GeV, which is the most precise estimation up to date and is dominated by the systematic effects. There is no hint of the integral flux variability on daily scales at energies above 300 GeV when systematic uncertainties are included in the flux measurement. We consider three state- of-the-art theoretical models to describe the overall spectral energy distribution of the Crab Nebula. The constant B-field model cannot satisfactorily reproduce the VHE spectral measurements presented in this work, having particular difficulty reproducing the broadness of the observed IC peak. Most probably this implies that the assumption of the homogeneity of the magnetic field inside the nebula is incorrect. On the other hand, the time-dependent 1D spectral model provides a good fit of the new VHE results when considering a 80 {\mu}G magnetic field. However, it fails to match the data when including the morphology of the nebula at lower wavelengths., Comment: accepted by JHEAp, 9 pages, 6 figures

Published
2015
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5. Diode laser spectroscopy of methyl chloride overtones at 850–860 nm.

Author

Lucchesini, A. and Gozzini, S.

Subjects
*SEMICONDUCTOR lasers, *LASER spectroscopy, *GALLIUM arsenide, *METHYL chloride, *ABSORPTION
Abstract

By using a tunable diode laser (TDL) spectrometer 156 CH 3 Cl overtone absorption lines have been detected in the range between 11,590 and 11,760 cm −1 (8500–8625 Å). Their strengths range around 10 − 26 – 10 − 27 cm / molecule and have been measured by utilizing commercial AlGaAs/GaAs laser diodes through the wavelength modulation spectroscopy (WMS) and the 2nd harmonic (2 f ) detection techniques. For one line the self-broadening coefficient has been obtained. [ABSTRACT FROM AUTHOR]

Published
2016
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6. Diode laser spectroscopy of methyl fluoride overtones at 850nm.

Author

Lucchesini, A. and Gozzini, S.

Subjects
*FLUOROMETHANE, *SEMICONDUCTOR lasers, *LASER spectroscopy, *SPECTRAL lines, *WAVELENGTHS, *TEMPERATURE effect
Abstract

Abstract: One hundred fifty-six 12CH3F overtone absorption lines, comprised between 11545 and 11836cm−1, have been observed by using a tunable diode laser (TDL) spectrometer. Their intensities range around 10−26 cm/molecule and have been measured by utilizing commercial AlGaAs/GaAs laser diodes through the wavelength modulation (WM) and the 2nd harmonic (2f) detection techniques. Self-broadening coefficients and line strengths have been measured at room temperature for seven of the strongest transitions, while air-broadening coefficients have been obtained for two lines. In addition, self- and air-collisional shifts have been measured for the 11564.25cm−1 transition. [Copyright &y& Elsevier]

Published
2013
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7. Diode laser spectroscopy of ethylene overtones at 830nm

Author

Lucchesini, A. and Gozzini, S.

Subjects
*ETHYLENE, *LASER spectroscopy, *SEMICONDUCTOR lasers, *SECOND harmonic generation, *SPECTRAL line broadening, *HETEROSTRUCTURES
Abstract

Abstract: A tunable diode laser spectrometer has been employed to examine the 3rd overtone absorption lines of C2H4 at around 12000cm−1 (830nm). The spectrometer sources are heterostructure AlGaAs tunable diode lasers operating “free-running”. By the aid of the wavelength modulation spectroscopy with the second harmonic detection technique and a Herriott type multipass cell 63 very weak absorption lines have been observed for the first time, with cross sections as low as 2 × 10−26 cm2/mol, equivalent to . The self-broadening coefficient has been measured for one of the most intense lines. [Copyright &y& Elsevier]

Published
2011
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8. Diode laser spectroscopy of ammonia at 760nm

Author

Lucchesini, A. and Gozzini, S.

Subjects
*LASER spectroscopy, *AMMONIA, *TUNABLE lasers, *SEMICONDUCTOR diodes, *ABSORPTION spectra, *HETEROSTRUCTURES, *ALUMINUM compounds, *WAVELENGTHS
Abstract

Abstract: A tunable diode laser spectrometer has been employed to examine the unknown overtone absorption lines of around (760nm). The spectrometer sources are commercially available heterostructure AlGaAs tunable diode lasers operating in the “free-running” mode. The detection of the lines has been possible by the use of the wavelength modulation spectroscopy and the second harmonic detection technique. A special algorithm has been used in order to fit the highly modulated absorption lines. The weakest observed resonances have absorption cross sections on the order of ≃/molecule or ≃/amagat. For some of the more intense lines self-, air-, -, He- and -broadening coefficients have been obtained at room temperature and also some shifting coefficients have been measured. [Copyright &y& Elsevier]

Published
2009
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9. Methane diode laser overtone spectroscopy at 840nm

Author

Lucchesini, A. and Gozzini, S.

Subjects
*MANURE gases, *SPECTRUM analysis, *ABSORPTION, *SPECTROMETERS
Abstract

Abstract: Overtone absorption lines of 12 have been examined by using a tunable diode laser (TDL) spectrometer in the region around (840nm) where the combination overtone band lies. The spectrometer sources are commercially available heterostructure GaAlAs TDLs operating in the “free-running” mode, which allowed the detection of the line positions within . The wavelength modulation spectroscopy (WMS) and the second harmonic detection technique permitted the measurements of minimum absorbances of the order of . This allowed to observe the weakest lines of the band with absorption cross-sections of the order of cm/molecule or /amagat. For some of them self-, air-, He- and H-broadening coefficients have been obtained at room temperature. [Copyright &y& Elsevier]

Published
2007
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10. Diode laser spectroscopy of CO2 at 790nm

Author

Lucchesini, A. and Gozzini, S.

Subjects
*SPECTRUM analysis, *ABSORPTION, *CARBON dioxide, *LASER spectroscopy
Abstract

Abstract: Absorption lines of 12C16O2 have been examined by using a tunable diode laser spectrometer in the region around (790nm). The spectrometer sources are commercially available double heterostructure InGaAlAs tunable diode lasers (TDLs) operating in the “free-running” mode, which allowed the detection of the line positions within . The observed carbon dioxide absorption lines belong to the combination overtone ro-vibrational band with intensities ranging around . [Copyright &y& Elsevier]

Published
2007
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11. Diode laser overtone spectroscopy of CO2 at 780nm

Author

Lucchesini, A. and Gozzini, S.

Subjects
*ABSORPTION, *CARBON compounds, *CARBON dioxide, *SPECTROMETERS
Abstract

Abstract: Overtone absorption lines of 12C16O2 have been examined by using a tunable diode laser (TDL) spectrometer in the region around . The spectrometer sources are commercially available double heterostructure InGaAlAs TDLs operating in the “free-running” mode, which allowed the detection of the line positions within . The observed carbon dioxide absorption lines belong to the ro-vibrational band with rotational quantum number up to 48. The minimum absorbance detected by the spectrometer permitted to observe the weakest lines having the absorption cross section of the order of . [Copyright &y& Elsevier]

Published
2005
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