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1. Summary of the SUSY Working Group of the 1999 Les Houches Workshop

Author

Abdullin, S., Drees, M., Martyn, H. -U., Polesello, G., Ambrosanio, S., Dreiner, H., Godbole, R. M., Wells, J., Chiappetta, P., Choudhury, D., Datta, A. K., Deandrea, A., Eboli, O. J. P., Ghodbane, N., Heinemeyer, S., Ilyin, V., Kon, T., Kraml, S., Kurihara, Y., Kuroda, M., Megner, L., Mele, B., Moreau, G., Mukhopadyaya, B., Nagy, E., Negroni, S., Odagiri, K., Paige, F. E., Perez, E., Petrarca, S., Richardson, P., Rimoldi, A., Roy, S., Seymour, M. H., Spira, M., Virey, J. M., Vissani, F., and Weiglein, G.

Subjects
High Energy Physics - Phenomenology
Abstract

The results obtained by the Working Group on Supersymmetry at the 1999 Les Houches Workshop on Collider Physics are summarized. Separate chapters treat "general" supersymmetry, R-parity violation, gauge mediated supersymmetry breaking, and anomaly mediated supersymmetry breaking., Comment: LaTeX, 110 pages with numerous .ps and .eps files. proc.tex is main tex file

Published
2000

3. First Results from the MATS Satellite Mission

Author

Gumbel, J., Megner, L., Murtagh, D., Ivchenko, N., Christenen, O., Linder, B., Hedin, J., Stegman, J., and Lindstein, C.

Abstract

Global three-dimensional data are a key to understanding gravity waves in the mesosphere and lower thermosphere. In November 2022, the Swedish MATS satellite was launched into orbit to address this need. MATS applies space-borne limb imaging in combination with tomographic and spectroscopic analysis to study 3D atmospheric structures over a wide range of spatial scales. Measurement targets are O2 Atmospheric Band airglow in the near infrared, and sunlight scattered from noctilucent clouds in the ultraviolet. This presentation provides an overview over first results from the mission. This includes an outlook on data availability, and examples of usage of the data., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023
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7. Performance of the ATLAS electromagnetic calorimeter barrel module 0

Author

Aubert, B., Ballansat, J., Bazan, A., Beaugiraud, B., Boniface, J., Chollet, F., Colas, J., Delebecque, P., Di Ciaccio, L., Dumont-Dayot, N., El Kacimi, M., Gaumer, O., Ghez, P., Girard, C., Gouanère, M., Kambara, H., Jérémie, A., Jézéquel, S., Lafaye, R., Leflour, T., Le Maner, C., Lesueur, J., Massol, N., Moynot, M., Neukermans, L., Perrodo, P., Perrot, G., Poggioli, L., Prast, J., Przysiezniak, H., Riccadona, X., Sauvage, G., Thion, J., Wingerter-Seez, I., Zitoun, R., Zolnierowski, Y., Chen, H., Citterio, M., Farrell, J., Gordon, H., Hackenburg, B., Hoffman, A., Kierstead, J., Lanni, F., Leite, M., Lissauer, D., Ma, H., Makowiecki, D., Radeka, V., Rahm, D., Rajagopalan, S., Rescia, S., Stumer, I., Takai, H., Yip, K., Benchekroun, D., Driouichi, C., Hoummada, A., Hakimi, M., Stroynowski, R., Ye, J., Beck Hansen, J., Belymam, A., Bremer, J., Chevalley, J.L., Fassnacht, P., Gianotti, F., Hervas, L., Marin, C.P., Pailler, P., Schilly, P., Seidl, W., Vossebeld, J., Vuillemin, V., Clark, A., Efthymiopoulos, I., Moneta, L., Belhorma, B., Collot, J., de Saintignon, P., Dzahini, D., Ferrari, A., Gallin-Martel, M.L., Hostachy, J.Y., Martin, P., Muraz, J.F., Ohlsson-Malek, F., Saboumazrag, S., Ban, J., Cartiglia, N., Cunitz, H., Dodd, J., Gara, A., Leltchouk, M., Negroni, S., Parsons, J.A., Seman, M., Simion, S., Sippach, W., Willis, W., Barreiro, F., Garcia, G., Labarga, L., Rodier, S., del Peso, J., Alexa, C., Barrillon, P., Benchouk, C., Chekhtman, A., Dinkespiler, B., Djama, F., Duval, P.Y., Henry-Couannier, F., Hinz, L., Jevaud, M., Karst, P., Le Van Suu, A., Martin, L., Martin, O., Mirea, A., Monnier, E., Nagy, E., Nicod, D., Olivier, C., Pralavorio, P., Repetti, B., Raymond, M., Sauvage, D., Tisserant, S., Toth, J., Wielers, M., Battistoni, G., Bonivento, W., Carminati, L., Cavalli, D., Costa, G., Delmastro, M., Fanti, M., Mandelli, L., Mazzanti, M., Perini, L., Resconi, S., Tartarelli, G.F., Aulchenko, V., Kazanin, V., Kolachev, G., Malyshev, V., Maslennikov, A., Pospelov, G., Snopkov, R., Shousharo, A., Talyshev, A., Tikhonov, Yu., Augé, E., Bourdarios, C., Breton, D., Cros, P., de La Taille, C., Falleau, I., Fournier, D., Guilhem, G., Hassani, S., Jacquier, Y., Kordas, K., Macé, G., Merkel, B., Noppe, J.M., Parrour, G., Pétroff, P., Puzo, P., Richer, J.P., Rousseau, D., Seguin-Moreau, N., Serin, L., Tocut, V., Veillet, J.J., Zerwas, D., Astesan, F., Bertoli, W., Camard, A., Canton, B., Fichet, S., Hubaut, F., Imbault, D., Lacour, D., Laforge, B., Le Dortz, O., Martin, D., Nikolic-Audit, I., Orsini, F., Rossel, F., Schwemling, P., Cleland, W., McDonald, J., Abouelouafa, E.M., Ben Mansour, A., Cherkaoui, R., El Mouahhidi, Y., Ghazlane, H., Idrissi, A., Belorgey, J., Bernard, R., Chalifour, M., Le Coroller, A., Ernwein, J., Mansoulié, B., Renardy, J.F., Schwindling, J., Taguet, J.-P., Teiger, J., Clément, C., Lund-Jensen, B., Lundqvist, J., Megner, L., Pearce, M., Rydstrom, S., Egdemir, J., Engelmann, R., Hoffman, J., McCarthy, R., Rijssenbeek, M., and Steffens, J.

Published
2003
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8. Performance of the ATLAS electromagnetic calorimeter end-cap module 0

Author

Aubert, B, Ballansat, J, Bazan, A, Beaugiraud, B, Boniface, J, Chollet, F, Colas, J, Delebecque, P, Di Ciaccio, L, Dumont-Dayot, N, El Kacimi, M, Gaumer, O, Ghez, P, Girard, C, Gouanère, M, Kambara, H, Jérémie, A, Jézéquel, S, Lafaye, R, Leflour, T, Le Maner, C, Lesueur, J, Massol, N, Moynot, M, Neukermans, L, Perrodo, P, Perrot, G, Poggioli, L, Prast, J, Przysiezniak, H, Riccadona, X, Sauvage, G, Thion, J, Wingerter-Seez, I, Zitoun, R, Zolnierowski, Y, Chen, H, Citterio, M, Farrell, J, Gordon, H, Hackenburg, B, Hoffman, A, Kierstead, J, Lanni, F, Leite, M, Lissauer, D, Ma, H, Makowiecki, D, Radeka, V, Rahm, D, Rajagopalan, S, Rescia, S, Stumer, I, Takai, H, Yip, K, Benchekroun, D, Driouichi, C, Hoummada, A, Hakimi, M, Stroynowski, R, Ye, J, Beck Hansen, J, Belymam, A, Bremer, J, Chevalley, J.L, Fassnacht, P, Gianotti, F, Hervas, L, Marin, C.P, Pailler, P, Schilly, P, Seidl, W, Vossebeld, J, Vuillemin, V, Clark, A, Efthymiopoulos, I, Moneta, L, Belhorma, B, Collot, J, Ferrari, A, Gallin-Martel, M.L, Hostachy, J.Y, Martin, P, Ohlsson-Malek, F, Saboumazrag, S, Ban, J, Cartiglia, N, Cunitz, H, Dodd, J, Gara, A, Leltchouk, M, Negroni, S, Parsons, J.A, Seman, M, Simion, S, Sippach, W, Willis, W, Barreiro, F, Garcia, G, Labarga, L, Rodier, S, del Peso, J, Alexa, C, Barrillon, P, Benchouk, C, Chekhtman, A, Dinkespiler, B, Djama, F, Duval, P.Y, Henry-Couannier, F, Hinz, L, Jevaud, M, Karst, P, Le Van Suu, A, Martin, L, Martin, O, Mirea, A, Monnier, E, Nagy, E, Nicod, D, Olivier, C, Pralavorio, P, Repetti, B, Raymond, M, Sauvage, D, Tisserant, S, Toth, J, Wielers, M, Battistoni, G, Carminati, L, Costa, G, Delmastro, M, Fanti, M, Mandelli, L, Mazzanti, M, Tartarelli, G.F, Aulchenko, V, Kazanin, V, Kolachev, G, Malyshev, V, Maslennikov, A, Pospelov, G, Snopkov, R, Shousharo, A, Talyshev, A, Tikhonov, Yu, Augé, E, Bourdarios, C, Breton, D, Bonivento, W, Cros, P, de La Taille, C, Falleau, I, Fournier, D, Guilhem, G, Hassani, S, Jacquier, Y, Kordas, K, Macé, G, Merkel, B, Noppe, J.M, Parrour, G, Pétroff, P, Puzo, P, Richer, J.P, Rousseau, D, Seguin-Moreau, N, Serin, L, Tocut, V, Veillet, J.J, Zerwas, D, Astesan, F, Bertoli, W, Camard, A, Canton, B, Fichet, S, Hubaut, F, Imbault, D, Lacour, D, Laforge, B, Le Dortz, O, Martin, D, Nikolic-Audit, I, Orsini, F, Rossel, F, Schwemling, P, Cleland, W, McDonald, J, Abouelouafa, E.M, Ben Mansour, A, Cherkaoui, R, El Mouahhidi, Y, Ghazlane, H, Idrissi, A, Belorgey, J, Bernard, R, Chalifour, M, Le Coroller, A, Ernwein, J, Mansoulié, B, Renardy, J.F, Schwindling, J, Taguet, J.-P, Teiger, J, Clément, C, Lund-Jensen, B, Lundqvist, J, Megner, L, Pearce, M, Rydstrom, S, Egdemir, J, Engelmann, R, Hoffman, J, McCarthy, R, Rijssenbeek, M, and Steffens, J

Published
2003
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9. Production and transport mechanisms of NO in the polar upper mesosphere and lower thermosphere in observations and models

Author

Hendrickx, K, Megner, L, Marsh, DR, and Smith-Johnsen, C

Abstract

A reservoir of nitric oxide (NO) in the lower thermosphere efficiently cools the atmosphere after periods of enhanced geomagnetic activity. Transport from this reservoir to the stratosphere within the winter polar vortex allows NO to deplete ozone levels and thereby affect the middle atmospheric heat budget. As more climate models resolve the mesosphere and lower thermosphere (MLT) region, the need for an improved representation of NO-related processes increases. This work presents a detailed comparison of NO in the Antarctic MLT region between observations made by the Solar Occultation for Ice Experiment (SOFIE) instrument on-board the Aeronomy of Ice in the Mesosphere (AIM) satellite and simulations performed by the Whole Atmosphere Community Climate Model with Specified Dynamics (SD-WACCM). We investigate 8 years of SOFIE observations, covering the period 2007–2015, and focus on the Southern Hemisphere (SH), rather than on dynamical variability in the Northern Hemisphere (NH) or a specific geomagnetic perturbed event. The morphology of the simulated NO is in agreement with observations though the long-term mean is too high and the short-term variability is too low in the thermosphere. Number densities are more similar during winter, though the altitude of peak NO density, which reaches between 102 and 106 km in WACCM and between 98 and 104 km in SOFIE, is most separated during winter. Using multiple linear regression (MLR) and superposed epoch analysis (SEA) methods, we investigate how well the NO production and transport are represented in the model. The impact of geomagnetic activity is shown to drive NO variations in the lower thermosphere similarly across both datasets. The dynamical transport from the lower thermosphere into the mesosphere during polar winter is found to agree very well with a descent rate of about 2.2 km day−1 in the 80–110 km region in both datasets. The downward-transported NO fluxes are, however, too low in WACCM, which is likely due to medium energy electrons (MEE) and D-region ion chemistry that are not represented in the model. publishedVersion

Published
2018

11. Relative Importance of Nitric Oxide Physical Drivers in the Lower Thermosphere

Author

Hendrickx, K, Megner, L, Marsh, DR, Gumbel, J, Strandberg, R, and Martinsson, F

Subjects
Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, Physics::Atmospheric and Oceanic Physics, Physics::Geophysics
Abstract

Nitric oxide (NO) observations from the Solar Occultation for Ice Experiment and Student Nitric Oxide Explorer satellite instruments are investigated to determine the relative importance of drivers of short‐term NO variability. We study the variations of deseasonalized NO anomalies by removing a climatology, which explains between approximately 70% and 90% of the total NO budget, and relate them to variability in geomagnetic activity and solar radiation. Throughout the lower thermosphere geomagnetic activity is the dominant process at high latitudes, while in the equatorial region solar radiation is the primary source of short‐term NO changes. Consistent results are obtained on estimated geomagnetic and radiation contributions of NO variations in the two data sets, which are nearly a decade apart in time. The analysis presented here can be applied to model simulations of NO to investigate the accuracy of the parametrized physical drivers.

Published
2017

12. Observations and Modeling of Increased Nitric Oxide in the Antarctic Polar Middle Atmosphere Associated With Geomagnetic Storm‐Driven Energetic Electron Precipitation

Author

Newnham, D. A., primary, Clilverd, M. A., additional, Rodger, C. J., additional, Hendrickx, K., additional, Megner, L., additional, Kavanagh, A. J., additional, Seppälä, A., additional, Verronen, P. T., additional, Andersson, M. E., additional, Marsh, D. R., additional, Kovács, T., additional, Feng, W., additional, and Plane, J. M. C., additional

Published
2018
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13. Characterisation of the analogue read-out chain for the CCDs onboard the Mesospheric Airglow/Aerosol Tomography and Spectroscopy (MATS)

Author

Giono, G., Olentsenko, G., Ivchenko, N., Christensen, O. M., Gumbel, J., Frisk, U., Hammar, A., Davies, I., Megner, L., Giono, G., Olentsenko, G., Ivchenko, N., Christensen, O. M., Gumbel, J., Frisk, U., Hammar, A., Davies, I., and Megner, L.

Abstract

The MATS satellite aims at observing airglow and noctilucent clouds in the mesosphere. The main instrument consists of a six channels limb imager in the near-ultraviolet and near-infrared. A high signal-to-noise ratio is required for detecting these mesospheric phenomena: 100 and 500 for ultraviolet and infrared, respectively. This is achieved by an optical design minimizing stray-light, but also with a dedicated design of the read-out analogue chain for the CCD on each channel. The requirements and expected light level on the imaging channels are briefly discussed before focusing on the CCD read-out analogue chain, for which the design and performances are presented., QC 20181210

Published
2018
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14. Observations and modelling of increased nitric oxide in the Antarctic polar middle atmosphere associated with geomagnetic storm driven energetic electron precipitation

Author

Newnham, David A., Clilverd, Mark A., Rodger, C.J., Hendrickx, K., Megner, L., Kavanagh, Andrew J., Seppälä, A., Verronen, P.T., Andersson, M.E., Marsh, D.R., Kovács, T., Feng, W., Plane, J.M.C., Newnham, David A., Clilverd, Mark A., Rodger, C.J., Hendrickx, K., Megner, L., Kavanagh, Andrew J., Seppälä, A., Verronen, P.T., Andersson, M.E., Marsh, D.R., Kovács, T., Feng, W., and Plane, J.M.C.

Abstract

Nitric oxide (NO) produced in the polar middle and upper atmosphere by energetic particle precipitation depletes ozone in the mesosphere and, following vertical transport in the winter polar vortex, in the stratosphere. Medium energy electron (MEE) ionization by 30–1000 keV electrons during geomagnetic storms may have a significant role in mesospheric NO production. However, questions remain about the relative importance of direct NO production by MEE at altitudes ~60–90 km versus indirect NO originating from auroral ionization above 90 km. We investigate potential drivers of NO variability in the southern‐hemisphere mesosphere and lower thermosphere during 2013–14. Contrasting geomagnetic activity occurred during the two austral winters, with more numerous moderate storms in the 2013 winter. Ground‐based millimeter‐wave observations of NO from Halley, Antarctica are compared with measurements by the Solar Occultation For Ice Experiment (SOFIE) space‐borne spectrometer. NO partial columns over the altitude range 65–140 km from the two observational datasets show large day to day variability and significant disagreement, with Halley values on average 49% higher than the corresponding SOFIE data. SOFIE NO number densities, zonally averaged over geomagnetic latitudes ‐59°to ‐65°, are up to 3×108 cm‐3 higher in the winter of 2013 compared to 2014. Comparisons with a new version of the Whole Atmosphere Community Climate Model, which includes detailed D‐region ion chemistry (WACCM‐SIC) and MEE ionization rates, show that the model underestimates NO in the winter lower mesosphere whereas thermospheric abundances are too high. This indicates the need to further improve and verify WACCM‐SIC with respect to MEE ionization, thermospheric NO chemistry, and vertical transport.

Published
2018

17. Distribution of meteoric smoke ? sensitivity to microphysical properties and atmospheric conditions

Author

Megner, L., Markus Rapp, Gumbel, J., Department of Meteorology [Stockholm] (MISU), Stockholm University, and Leibniz-Institute of Atmospheric Physics (AIP)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere
Abstract

International audience; Meteoroids entering the Earth's atmosphere experience strong deceleration and ablate, whereupon the resulting material is believed to re-condense to nanometre-size "smoke particles". These particles are thought to be of great importance for many middle atmosphere phenomena, such as noctilucent clouds, polar mesospheric summer echoes, metal layers, and heterogeneous chemistry. The properties and distribution of meteoric smoke depend on poorly known or highly variable factors such as the amount, composition and velocity of incoming meteoric material, the efficiency of coagulation, and the state and circulation of the atmosphere. This work uses a one-dimensional microphysical model to investigate the sensitivities of meteoric smoke properties to these poorly known or highly variable factors. The resulting uncertainty or variability of meteoric smoke quantities such as number density, mass density, and size distribution are determined. It is found that the two most important factors are the efficiency of the coagulation and background vertical wind. The seasonal variation of the vertical wind in the mesosphere implies strong global and temporal variations in the meteoric smoke distribution. This contrasts the simplistic picture of a homogeneous global meteoric smoke layer, which is currently assumed in many studies of middle atmospheric phenomena. In particular, our results suggest a very low number of nanometre-sized smoke particles at the summer mesopause where they are thought to serve as condensation nuclei for noctilucent clouds.

Published
2006

20. Muon Signal in the Electromagnetic Barrel Calorimeter Module 0 from August -99 and May -00 Testbeam Data

Author

Megner, L

Subjects
Physics::Instrumentation and Detectors, Physics::Accelerator Physics, High Energy Physics::Experiment, Detectors and Experimental Techniques
Abstract

Test beam data from the Electromagnetic Calorimeter Module 0 has been analyzed, and a signal from muons has been detected. The data was taken in August -99 and May -00 at CERN. The signal to noise ratio for muons has been determined for the different layers of the Calorimeter. The percentage of the total energy that was deposited in the Front, Middle and Back compartments has been determined.

Published
2001

21. Summary of the SUSY Working Group of the 1999 Les Houches Workshop

Author

Abdullin, S, Drees, M, Martyn, HU, Polesello, G, Ambrosanio, S, Dreiner, H, Godbole, RM, Wells, J, Chiappetta, P, Choudhury, D, Datta, AK, Deandrea, A, Eboli, OJP, Ghodbane, N, Heinemeyer, S, Ilyin, V, Kon, T, Kraml, S, Kurihara, Y, Kuroda, M, Megner, L, Mele, B, Moreau, G, Mukhopadyaya, B, Nagy, E, Negroni, S, Odagiri, K, Paige, FE, Perez, E, Petrarca, S, Richardson, P, Rimoldi, A, Roy, S, Seymour, MH, Spira, M, Virey, JM, Vissani, F, and Weiglein, G

Subjects
High Energy Physics - Phenomenology, High Energy Physics::Theory, High Energy Physics - Phenomenology (hep-ph), High Energy Physics::Phenomenology, FOS: Physical sciences, Centre for Theoretical Studies (Ceased to exist at the end of 2003), Centre for Theoretical Studies, Particle Physics - Phenomenology
Abstract

The results obtained by the Working Group on Supersymmetry at the 1999 Les Houches Workshop on Collider Physics are summarized. Separate chapters treat "general" supersymmetry, R-parity violation, gauge mediated supersymmetry breaking, and anomaly mediated supersymmetry breaking., Comment: LaTeX, 110 pages with numerous .ps and .eps files. proc.tex is main tex file

Published
2000

22. Summary of the SUSY Working Group

Author

Abdullin, S., Drees, M., Martyn, H U., Ambrosanio, S., Dreiner, H., Godbole, R M., Chiappetta, J., Choudhury, D., Datta, A K., Deandrea, A., Eboli, O J P., Ghodbane, N., Heinemeyer, S., Ilyin, V., Kon, T., Kraml, S., Kurihara, Y., Kuroda, M., Megner, L., Mele, B., Moreau, G., Mukhopadyaya, B., Nagy, E., Negroni, S., Odagiri, K., Paige, F E., Perez, Emile, Petrarca, S., Richardson, P., Rimoldi, A., Roy, Sylvaine, Seymour, M H., Spira, M., Virey, J M., Vissani, F., Weiglein, G., Polesello, G., Wells, J., Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Flores, Sylvie

Subjects
High Energy Physics::Theory, [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Phenomenology, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]
Abstract

The results obtained by the Working Group on Supersymmetry at the 1999 Les Houches Workshop on Collider Physics are summarized. Separate chapters treat "general" supersymmetry, R-parity violation, gauge mediated supersymmetry breaking, and anomaly mediated supersymmetry breaking.

Published
1999

23. Global and Temporal Distribution of Meteoric Smoke: A Two-Dimensional Simulation Study

Author

STOCKHOLM UNIV (SWEDEN), Megner, L., Siskind, D. E., Rapp, M., Gumbel, J., STOCKHOLM UNIV (SWEDEN), Megner, L., Siskind, D. E., Rapp, M., and Gumbel, J.

Abstract

Meteoric material entering Earth's atmosphere ablates in the mesosphere and is then expected to recondense into tiny so-called "smoke particles." These particles are thought to be of great importance for middle atmosphere phenomena like noctilucent clouds, polar mesospheric summer echoes, metal layers, and heterogeneous chemistry. Commonly used one-dimensional (1-D) meteoric smoke profiles refer to average global conditions and yield of the order of a thousand nanometer sized particles per cubic centimeter at the mesopause, independent of latitude and time of year. Using the first two-dimensional model of both coagulation and transport of meteoric material we here show that such profiles are too simplistic, and that the distribution of smoke particles indeed is dependent on both latitude and season. The reason is that the atmospheric circulation, which cannot be properly handled by 1-D models, efficiently transports the particles to the winter hemisphere and down into the polar vortex. Using the assumptions commonly used in 1-D studies results in number densities of nanometer sized particles of around 4000/cc at the winter pole, while very few particles remain at the Arctic summer mesopause. If smoke particles are the only nucleation kernel for ice in the mesosphere this would imply that there could only be of the order of 100 or less ice particles per cc at the Arctic summer mesopause. This is much less than the ice number densities expected for the formation of ice phenomena (noctilucent clouds and polar mesospheric summer echoes) that commonly occur in this region. However, we find that especially the uncertainty of the amount of material that is deposited in Earth's atmosphere imposes a large error bar on this number, which may allow for number densities up to 1000/cc near the polar summer mesopause., Published in Journal of Geophysical Research, v113 D03202 p1-15, 2008.

Published
2008

25. Mass analysis of charged aerosol particles in NLC and PMSE during the ECOMA/MASS campaign

Author

Robertson, S., primary, Horányi, M., additional, Knappmiller, S., additional, Sternovsky, Z., additional, Holzworth, R., additional, Shimogawa, M., additional, Friedrich, M., additional, Torkar, K., additional, Gumbel, J., additional, Megner, L., additional, Baumgarten, G., additional, Latteck, R., additional, Rapp, M., additional, Hoppe, U.-P., additional, and Hervig, M. E., additional

Published
2009
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30. Erratum to “Performance of the ATLAS electromagnetic calorimeter barrel module 0” [Nucl. Instr. and Meth. A 500 (2003) 202–231]

Author

Aubert, B., primary, Ballansat, J., additional, Bazan, A., additional, Beaugiraud, B., additional, Boniface, J., additional, Chollet, F., additional, Colas, J., additional, Delebecque, P., additional, Di Ciaccio, L., additional, Dumont-Dayot, N., additional, El Kacimi, M., additional, Gaumer, O., additional, Ghez, P., additional, Girard, C., additional, Gouanère, M., additional, Kambara, H., additional, Jérémie, A., additional, Jézéquel, S., additional, Lafaye, R., additional, Leflour, T., additional, Le Maner, C., additional, Lesueur, J., additional, Massol, N., additional, Moynot, M., additional, Neukermans, L., additional, Perrodo, P., additional, Perrot, G., additional, Poggioli, L., additional, Prast, J., additional, Przysiezniak, H., additional, Riccadona, X., additional, Sauvage, G., additional, Thion, J., additional, Wingerter-Seez, I., additional, Zitoun, R., additional, Zolnierowski, Y., additional, Chen, H., additional, Citterio, M., additional, Farrell, J., additional, Gordon, H., additional, Hackenburg, B., additional, Hoffman, A., additional, Kierstead, J., additional, Lanni, F., additional, Leite, M., additional, Lissauer, D., additional, Ma, H., additional, Makowiecki, D., additional, Radeka, V., additional, Rahm, D., additional, Rajagopalan, S., additional, Rescia, S., additional, Stumer, I., additional, Takai, H., additional, Yip, K., additional, Benchekroun, D., additional, Driouichi, C., additional, Hoummada, A., additional, Hakimi, M., additional, Stroynowski, R., additional, Ye, J., additional, Beck Hansen, J., additional, Belymam, A., additional, Bremer, J., additional, Chevalley, J.L., additional, Fassnacht, P., additional, Gianotti, F., additional, Hervas, L., additional, Marin, C.P., additional, Pailler, P., additional, Schilly, P., additional, Seidl, W., additional, Vossebeld, J., additional, Vuillemin, V., additional, Clark, A., additional, Efthymiopoulos, I., additional, Moneta, L., additional, Belhorma, B., additional, Collot, J., additional, de Saintignon, P., additional, Dzahini, D., additional, Ferrari, A., additional, Gallin-Martel, M.L., additional, Hostachy, J.Y., additional, Martin, P., additional, Muraz, J.F., additional, Ohlsson-Malek, F., additional, Saboumazrag, S., additional, Ban, J., additional, Cartiglia, N., additional, Cunitz, H., additional, Dodd, J., additional, Gara, A., additional, Leltchouk, M., additional, Negroni, S., additional, Parsons, J.A., additional, Seman, M., additional, Simion, S., additional, Sippach, W., additional, Willis, W., additional, Barreiro, F., additional, Garcia, G., additional, Labarga, L., additional, Rodier, S., additional, del Peso, J., additional, Alexa, C., additional, Barrillon, P., additional, Benchouk, C., additional, Chekhtman, A., additional, Dinkespiler, B., additional, Djama, F., additional, Duval, P.Y., additional, Henry-Couannier, F., additional, Hinz, L., additional, Jevaud, M., additional, Karst, P., additional, Le Van Suu, A., additional, Martin, L., additional, Martin, O., additional, Mirea, A., additional, Monnier, E., additional, Nagy, E., additional, Nicod, D., additional, Olivier, C., additional, Pralavorio, P., additional, Repetti, B., additional, Raymond, M., additional, Sauvage, D., additional, Tisserant, S., additional, Toth, J., additional, Wielers, M., additional, Battistoni, G., additional, Bonivento, W., additional, Carminati, L., additional, Cavalli, D., additional, Costa, G., additional, Delmastro, M., additional, Fanti, M., additional, Mandelli, L., additional, Mazzanti, M., additional, Perini, L., additional, Resconi, S., additional, Tartarelli, G.F., additional, Aulchenko, V., additional, Kazanin, V., additional, Kolachev, G., additional, Malyshev, V., additional, Maslennikov, A., additional, Pospelov, G., additional, Snopkov, R., additional, Shousharo, A., additional, Talyshev, A., additional, Tikhonov, Yu., additional, Augé, E., additional, Bourdarios, C., additional, Breton, D., additional, Cros, P., additional, de La Taille, C., additional, Falleau, I., additional, Fournier, D., additional, Guilhem, G., additional, Hassani, S., additional, Jacquier, Y., additional, Kordas, K., additional, Macé, G., additional, Merkel, B., additional, Noppe, J.M., additional, Parrour, G., additional, Pétroff, P., additional, Puzo, P., additional, Richer, J.P., additional, Rousseau, D., additional, Seguin-Moreau, N., additional, Serin, L., additional, Tocut, V., additional, Veillet, J.J., additional, Zerwas, D., additional, Astesan, F., additional, Bertoli, W., additional, Camard, A., additional, Canton, B., additional, Fichet, S., additional, Hubaut, F., additional, Imbault, D., additional, Lacour, D., additional, Laforge, B., additional, Le Dortz, O., additional, Martin, D., additional, Nikolic-Audit, I., additional, Orsini, F., additional, Rossel, F., additional, Schwemling, P., additional, Cleland, W., additional, McDonald, J., additional, Abouelouafa, E.M., additional, Ben Mansour, A., additional, Cherkaoui, R., additional, El Mouahhidi, Y., additional, Ghazlane, H., additional, Idrissi, A., additional, Belorgey, J., additional, Bernard, R., additional, Chalifour, M., additional, Le Coroller, A., additional, Ernwein, J., additional, Mansoulié, B., additional, Renardy, J.F., additional, Schwindling, J., additional, Taguet, J.-P., additional, Teiger, J., additional, Clément, C., additional, Lund-Jensen, B., additional, Lundqvist, J., additional, Megner, L., additional, Pearce, M., additional, Rydstrom, S., additional, Egdemir, J., additional, Engelmann, R., additional, Hoffman, J., additional, McCarthy, R., additional, Rijssenbeek, M., additional, and Steffens, J., additional

Published
2004
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31. Linearity aspects of the ensemble of data assimilations technique.

Author

Megner, L., Tan, D. G. H., Körnich, H., Isaksen, L., Horányi, A., Stoffelen, A., and Marseille, G.‐J.

Subjects
*ASTRONOMICAL perturbation, *NUMERICAL weather forecasting, *WEATHER forecasting, *TROPOSPHERE, *TROPOSPHERIC ozone, *STRATOSPHERE, *OZONE layer
Abstract

We examine the linearity of the Ensemble of Data Assimilations ( EDA) technique with respect to the amplitude of the applied observation perturbations. We provide explicit examples to assess the linear relationship between such modifications of the observing system and the resulting changes in the EDA ensemble spread. The results demonstrate that, for a state-of-the-art numerical weather prediction ( NWP) system, such linearity between the applied observation perturbations and the EDA ensemble spread holds well for temporal and spatial regimes relevant to global medium-range weather prediction: specifically, for forecast lead-times of up to approximately 5 days, in the vertical throughout the troposphere up to the lower and middle stratosphere and for broad horizontal scales. [ABSTRACT FROM AUTHOR]

Published
2015
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32. The SUSY working group: Summary report

Author

Abdullin, S., Drees, Manuel, Martyn, H. U., Polesello, G., Ambrosanio, S., Dreiner, Herbert K., Godbole, R. M., James Daniel Wells, Chiappetta, P., Choudhury, D., Datta, A. K., Deandrea, A., Eboli, Oscar J. P., Ghodbane, N., Heinemeyer, S., Ilyin, V., Kon, T., Kraml, S., Kurihara, Y., Kuroda, M., Megner, L., Mele, B., Moreau, G., Mukhopadyaya, B., Nagy, E., Negroni, S., Odagiri, K., Paige, F. E., Perez, E., Petrarca, S., Richardson, P., Rimoldi, A., Roy, S., Seymour, M. H., Spira, M., Virey, J. M., Vissani, F., and Weiglein, G.

33. Flight model characterization of the wide-field off-axis telescope for the MATS satellite.

Author

Park W, Hammar A, Pak S, Chang S, Gumbel J, Megner L, Christensen OM, Rouse J, and Kim DW

Abstract

We present optical characterization, calibration, and performance tests of the Mesospheric Airglow/Aerosol Tomography Spectroscopy (MATS) satellite, which for the first time, to the best of our knowledge, for a satellite, applies a linear-astigmatism-free confocal off-axis reflective optical design. Mechanical tolerances of the telescope were investigated using Monte Carlo methods and single-element perturbations. The sensitivity analysis results indicate that tilt errors of the tertiary mirror and a surface RMS error of the secondary mirror mainly degrade optical performance. From the Monte Carlo simulation, the tolerance limits were calculated to ±0.5 m m , ±1 m m , and ±0.15 ∘ for decenter, despace, and tilt, respectively. We performed characterization measurements and optical tests with the flight model of the satellite. Multi-channel relative pointing, total optical system throughput, and distortion of each channel were characterized for end-users. Optical performance was evaluated by measuring the modulation transfer function (MTF) and point spread function (PSF). The final MTF performance was 0.25 MTF at 20 lp/mm for the ultraviolet channel (304.5 nm), and 0.25-0.54 MTF at 10 lp/mm for infrared channels. The salient fact of the PSF measurement of this system is that there is no noticeable linear astigmatism detected over a wide field of view (5.67 ∘ ×0.91 ∘ ). All things considered, the design method showed great advantages in wide field of view observations with satellite-level optical performance.

Published
2020
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