La structure nucléaire en couches évolue en allant vers des régions de plus en plus exotiques de la carte des noyaux, et par conséquent, les nombres magiques conventionnels (8, 20, 28, 50, 82, 126) peuvent disparaître loin de la stabilité, tandis que de nouveaux nombres magiques peuvent apparaître. Le noyau de ⁷⁸Ni, avec 28 protons et 50 neutrons, est un des noyaux supposés doublement magiques les plus exotiques et est donc d'un grand intérêt. L'évolution de la fermeture de couche à Z = 28 en allant vers N = 50 peut être étudiée en sondant le caractère de particule individuelle des niveaux dans la chaîne isotopique de cuivre, ayant un proton de plus que le nickel. Ce travail porte sur le ⁷⁹Cu, à N = 50. Afin d'effectuer la première spectroscopie gamma en ligne des noyaux autour du ⁷⁸Ni, une expérience a été réalisée à la Radioactive Ion Beam Factory du RIKEN, au Japon. Le noyau de ⁷⁹Cu était produit par la réaction de knockout (p,2p) à partir d'un faisceau de ⁸⁰Zn envoyé sur le dispositif MINOS, une cible d'hydrogène liquide couplée à une TPC servant à reconstruire la trajectoire des protons. L'émission de rayons gamma subséquente était détectée en vol par le scintillateur segmenté DALI2. Les spectromètres BigRIPS et ZeroDegree permettaient, respectivement, une identification sans ambiguïté des noyaux entrants et sortants.Une procédure d'analyse basée sur des coïncidences gamma-gamma a permis de construire le premier schéma de niveau du ⁷⁹Cu, avec des états jusqu'à 4.6 MeV, et les résultats ont été comparés à des calculs de modèle en couches Monte Carlo. Les conclusions montrent que le noyau de ⁷⁹Cu est bien décrit en termes d'un proton de valence en dehors d'un cœur fermé de ⁷⁸Ni, ce qui implique le caractère magique de ce dernier. / The nuclear shell structure is evolving when going into more and more exotic regions of the chart of isotopes and consequently, the conventional magic numbers (8, 20, 28, 50, 82, 126) may disappear far from stability, while some new magic numbers can appear. The ⁷⁸Ni nucleus, with its 28 protons and 50 neutrons, is one of the most exotic supposedly doubly-magic nuclei, making it of great interest. The evolution of the Z = 28 gap towards N = 50 can be studied by probing the single-particle character of the states in the copper isotopic chain, having one proton more than nickel. This work focuses on Cu, at N = 50.In the aim of performing the first in-beam gamma-ray spectroscopy of nuclei in the close vicinity of ⁷⁸Ni, an experiment was carried out at the Radioactive Isotope Beam Factory of RIKEN, in Japan. The ⁷⁹Cu nucleus was produced through the (p,2p) knockout reaction from a ⁸⁰Zn beam sent on the MINOS device, a liquid-hydrogen target coupled to a TPC used for proton tracking. The subsequent gamma-decay was detected in-beam with the DALI2 scintillator array. The BigRIPS and ZeroDegree spectrometers allowed an unambiguous identification of the incoming and outgoing nuclei, respectively.An analysis procedure based on gamma-gamma coincidences permitted to build the first level scheme of ⁷⁹Cu, with levels up to 4.6 MeV, and the results were compared to Monte-Carlo shell-model calculations for interpretation. The conclusions show that the ⁷⁹Cu nucleus is well described in terms of a valence proton outside a closed ⁷⁸Ni core, implying the magic character of the latter.

La mesure des moments magnétiques nucléaires est d'une grande importance pour bien comprendre la structure nucléaire. Le moment magnétique est sensible à la nature de la particule indépendante. Le développement des faisceaux radioactifs permet aujourd'hui d'étudier les spins nucléaires et les moments de noyaux exotiques éloignés de la ligne de stabilité. Cependant, la mesure des moments magnétiques des noyaux radioactifs nécessite le développement des nouvelles méthodes fiables. Le développement réussi de telles méthodes ouvrirait la possibilité de découvrir de nouveaux phénomènes de structure nucléaire. L'étude présentée dans cette thèse est formée de deux expériences. La première expérience a été réalisée à ALTO à Orsay, en France. L'une des principales exigences pour mesurer un moment magnétique nucléaire est de produire un ensemble avec des spins orientés. Ce dernier peut être produit par un mécanisme de réaction approprié et une interaction de spin nucléaire avec le milieu environnant. Le degré d'orientation dépend du processus de formation et du mécanisme de réaction. Le but de cette première expérience était d’étudier le niveau d’orientation du spin nucléaire dans un mécanisme de réaction de fusion incomplète. Le résultat de l'expérience démontre la possibilité d'obtenir un alignement du spin dans une réaction de fusion incomplète d'un ordre de 20%. Ce mécanisme de réaction, avec une telle quantité d’alignement de spin, a le potentiel d’étudier la région riche en neutrons avec des faisceaux radioactifs. La deuxième expérience, et l'essentiel de la thèse, a été réalisée à HIE-ISOLDE au CERN. Cette expérience visait à obtenir des informations de haute précision sur le facteur g d’un état de courte durée. Une nouvelle méthode TDRIV (Time-Differential Recoil In Vacuum) a été appliquée pour la première fois avec des faisceaux radioactifs post-accélérés. La mesure du facteur g était réalisée pour le premier état excité dans un noyau de ²⁸Mg (Eₓ = 1474 (1) keV, T₁/₂ = 1,2 (1) ps). / Knowledge of the nuclear magnetic moments is of great importance to get a clear understanding of nuclear structure. The magnetic moment is sensitive to the single-particle nature of the valence nucleons. The development of radioactive beam facilities allows nowadays studying nuclear spins and moments of exotic nuclei which are far from the stability line. However, the measurement of magnetic moments of exotic nuclei produced as radioactive beams requires the development of reliable methods. Successful development of such methods would open up the possibility to discover new nuclear structure phenomena. The study outlined in this thesis is formed by two experiments. The first experiment was performed at ALTO facility in Orsay, France. One of the main requirements in order to measure a nuclear magnetic moment is to produce a spin-oriented ensemble. The latter can be produced by suitable reaction mechanism and nuclear spin interaction with the surrounding environment. The degree of the orientation depends on the formation process and reaction mechanism. The aim of this first experiment was investigating the level of nuclear spin orientation in incomplete fusion reaction mechanism. Two reaction channels were studied, the isomeric states in ⁶⁵mNi (I = 9/2⁺, Eₓ = 1017 keV, T₁/₂ = 26 ns), and ⁶⁶mCu (I = 6⁻, Eₓ = 563 keV, T₁/₂= 600 ns) with Time-Dependent Perturbed Angular Distribution (TDPAD) method. The result of the experiment demonstrates the possibility of obtaining spin alignment in incomplete fusion reaction of an order of 20%. This reaction mechanism, with such an important amount of spin alignment has potential near radioactive beam facilities to study the neutron-rich region with inverse kinematics reactions. The second experiment, and the main part of the thesis was performed at HIE-ISOLDE at CERN. This experiment aimed to obtain high precision g-factor information on a short-lived picosecond state. A new Time Differential Recoil-In-Vacuum (TDRIV) method was applied for the first time using post-accelerated radioactive beams. The g-factor measurement was performed for the first-excited state in ²⁸Mg nucleus (Eₓ = 1474(1) keV, T₁/₂ = 1.2(1) ps). Since the lifetime of the state is of the order of picoseconds, its g-factor can be measured only via the spin precession of the nucleus in an extremely strong magnetic field (kT). Such fields can only be produced at the nucleus by hyperfine interactions. In order to obtain a high precision on a g-factor measurement, a TDRIV calibration experiment was performed with a stable ²²Ne beam. This run allowed testing the system under the same conditions as with radioactive²⁸Mg beam. In addition, using the known g-factor of the first-excited state in ²²Ne allows to determine the absolute target-to-degrader distance so that to decrease the uncertainty and obtain a high precision g-factor measurement. The obtained calibration parameters from the ²²Ne data will be used in the determination of g-factor of ²⁸Mg.

One of the few attributes common to almost all living organisms is an ability to generate and maintain endogenous rhythms, which are controlled by a biological clock. The processes, which recur with a period of about 24 hours, are known as the circadian rhythms. The circadian clock controls rhythms of molecular, physiological as well as behavioral processes and adapts their activity to regularly appearing changes in day and night or season. In case of mammals, central oscillator is located in the hypothalamic suprachiasmatic nuclei (SCN). The SCN clock entrains rhythms of peripheral oscillators located in cells of other tissues. The central oscillator itself is synchronized with external environment mainly by a light-dark cycle, however, other cues can entrain the SCN clock as well. For example, during prenatal development, entrainment of a fetal clock is entirely dependent on non-photic cues derived from maternal organism. This study aimed to investigate a mechanism of the communication between the maternal and fetal central oscillators. A hypothesis was tested whether maternal melatonin may play a role in entrainment of the circadian clock in the fetal SCN. Furthermore, a mechanism, how melatonin may entrain the fetal clock was investigated at molecular level. The results provided evidence, that...

A change in atmospheric aerosol particles, especially cloud condensation nuclei (CCN) and ice-nucleating particles (INPs), is bound to impact cloud properties, precipitation and cloud radiative effects. In this thesis, two field campaigns were carried out in two representative locations, i.e. the anthropogenic polluted environment at Cyprus and the marine-dust intersect environment at Cabo Verde (a.k.a. Cape Verde) to understand the role of CCN and INPs over the tropical and subtropical regions in the northern hemisphere. On-line aerosol physical measurements were performed and samples from different environ- mental compartments were examined with respect to INPs: the oceanic sea surface microlayer (SML), underlying water (ULW), cloud water and atmospheric filters. Both measurement sites differ in aerosol properties, such as particle number size distribution, CCN and INP concentrations and CCN-derived particle hygroscopicity, due to different environment backgrounds and air mass origins. Aerosol particles at Cyprus were dominated by anthropogenic pollution, with small contributions of sea spray aerosol (SSA) and mineral dust. Particle aging process were observed through changes in CCN-derived particle hygroscopicity. New particle formation events with subsequent growth of the particles into the CCN size range were observed. INPs mainly originated from long-range transport. And anthropogenic pollution were found to be inefficient INPs at temperature range >−25 ◦C. However, aerosol particles at Cabo Verde featured a marine background with intrusions of dust. Dust and marine aerosols featured clearly different PNSDs. CCN number concentration at a supersaturation of 0.30% during the strongest observed dust periods was about 2.5 times higher than during marine periods. However, the CCN-derived hygroscopicity for marine and dust periods shows no significant difference. INPs at Cabo Verde were mainly in the supermicron size range, with a large contribution of biological particles. When comparing atmospheric INP number concentration to those found in seawater, it can be concluded that SSA only contributed a minor fraction to the atmospheric INP population.:1 Introduction 2 Methodology 3 Results and Discussion 4 Summary and Conclusions 5 Outlook Appendix Bibliography / Veränderungen im atmosphärischen Aerosol, speziell bei Wolkenkondensationskernen (CCN) und eisnukleierenden Partikeln (INPs), haben Auswirkungen auf Wolkeneigenschaften wie Niederschlagsbildung und Strahlung. Für die hier vorgelegte Arbeit wurden zwei Feldmesskampagnen durchgeführt, im anthropogen verschmutzten Zypern und auf Cabo Verde (alias Kap Verde), einer Schnittstelle zwischen Meer und Wüste. Ziel war es, die Rolle von CCN und INPs in den tropischen und subtropischen Regionen der nördlichen Hemisphäre besser zu verstehen. Es wurden aerosol-physikalische online Messungen durchgeführt und verschiedene Proben auf INPs hin untersucht: die Meeresoberflächen-Mikroschicht (SML), das darunter liegende Wasser (ULW), das Wolkenwasser und atmosphärische Filter. Die beiden verschiedenen Orte an denen die Messkampagnen stattfanden unterscheiden sich in den Aerosoleigenschaften wie z.B. Partikelanzahlgrößenverteilung (PNSD), CCN- und INP-Konzentration und der von CCN abgeleiteten Partikelhygroskopizität. Grund hierfür sind Unterschiede in der Umgebung und der Luftmassenherkunft. Die Aerosolpartikel auf Zypern wurden von anthropogener Verschmutzung dominiert, mit kleinen Beiträgen von Partikeln aus Meeres-Gischt (SSA) und Mineralstaub. Partikelalterung ging einher mit einer Veränderung der Hygroskopizität der CCN. Partikelneubildung wurde beobachtet, mit anschließendem Wachstum der Partikel bis in den CCN-Größenbereich. INPs stammen hauptsächlich aus Ferntransport, und Partikel aus anthropogener Verschmutzung waren ineffiziente INPs im Temperaturbereich >−25 ◦C. Das Aerosol in Cabo Verde speiste sich sowohl aus marinen Quellen als auch aus Wüstenstaub. Staub und marines Aerosol wiesen sehr verschiedene PNSDs auf. Die CCN-Anzahlkonzentration bei 0,30% Übersättigung war während der stärksten Staubperioden etwa 2,5 Mal höher als während der marinen Perioden. Die aus CCN abgeleitete Hygroskopizität zeigte jedoch keinen signifikanten Unterschied für marine und Staubperioden. Die INPs in Cabo Verde waren zum Großteil größer als ein Mikrometer, und waren zum Großteil biogenen Ursprungs. Aus dem Vergleich der atmosphärischen INP-Anzahlkonzentration mit der im Meerwasser gefundenen kann man schließen, dass SSA nur einen geringen Anteil zur atmosphärischen INP-Population beitrug.:1 Introduction 2 Methodology 3 Results and Discussion 4 Summary and Conclusions 5 Outlook Appendix Bibliography

Despite large efforts and decades of research, the scientific understanding of how aerosols impact climate by modulating microphysical cloud properties is still low and associated radiative forcing estimates (RFaci ) vary with a wide spread. But since anthropogenically forced aerosol-cloud interactions (ACI) are considered to oppose parts of the global warming, it is crucial to know their contribution to the total radiative forcing in order to improve climate predictions. To obtain a better understanding and quantification of ACI and the associated radiative effect it as been suggested to use concurrent measurements and observationally constrained model simulations. In this dissertation a joint satellite-reanalysis approach is introduced, bridging the gap between climate models and satellite observations in a bottom-up approach. This methodology involves an observationally constrained aerosol model, refined and concurrent multi-component satellite retrievals, a state-of-the-art aerosol activation parameteriza- tion as well as radiative transfer model. This methodology is shown here to be useful for a quantitative as well as qualitative analysis of ACI and for estimating RFaci . As a result, a 10-year long climatology of cloud condensation nuclei (CCN) (particles from which cloud droplets form) is produced and evaluated. It is the first of its kind providing 3-D CCN concentrations of global coverage for various supersaturations and aerosol species and offering the opportunity to be used for evaluation in models and ACI studies. Further, the distribution and variability of the resulting cloud droplet numbers and their susceptibility to changes in aerosols is explored and compared to previous estimates. In this context, an analysis by cloud regime has been proven useful. Last but not least, the computation and analysis of the present-day regime-based RFaci represents the final conclusion of the bottom-up methodology. Overall, this thesis provides a comprehensive assessment of interactions and uncertainties related to aerosols, clouds and radiation in regimes of liquid water clouds and helps to improve the level of scientific understanding.

In the mid-eighties, the development of radioactive-ion beams enabled the exploration ofregions of the nuclear landscape away from the valley of stability. Close to the neutrondripline, in the light neutron-rich region, halo nuclei were observed. These nuclei exhibit asurprisingly large matter radius and a strongly clusterized structure. These two featurescan be explained by the weak binding of one or two neutrons which allows them to tunnelfar from the rest of the nucleons, surrounding the nucleus by a diffuse halo. These nuclearstructures have challenged the usual description of the nucleus, described as a compactmany-body object with nucleons piling up into well defined orbitals. Because they areshort-lived, these nuclei are often studied through reaction processes, such as elasticscattering, breakup and knockout. To infer precise information from the experimentaldata, an accurate reaction model coupled with a realistic description of the nucleus isneeded.Compared to other state-of-the-art methods, the eikonal approximation is very cheapfrom a computational viewpoint. This model assumes that the projectile-target relativemotion does not differ much from the initial plane wave. It also makes the adiabaticapproximation, which sees the internal coordinates of the projectile as frozen during thecollision. These two assumptions hold for reactions occurring at high energy, i.e. above60 MeV/nucleon, in which the deflection of the projectile by the target is small and thecollision time is brief.In this thesis, I focus on improvements of the eikonal approximation. First, I studythe extension of the validity of the eikonal model down to 10 MeV/nucleon, in the energyrange of the facilities HIE-ISOLDE at CERN and ReA12 at the upcoming FRIB. To thisend, I analyse different corrections to the eikonal approximation, which account for thedeflection of the projectile by the target. I assess their accuracy for the elastic-scatteringand breakup observables of one-neutron halo nuclei at 10 MeV/nucleon. Next, I developa dynamical correction to the eikonal approximation, which applies to both nuclear andCoulomb interactions while conserving the eikonal numerical cost. I study this correctionin the cases of breakup reactions of one-neutron halo nuclei on light and heavy targets.Then, I investigate which nuclear-structure information can be inferred from knockoutreactions of one-neutron halo nuclei. To do so, I conduct a sensitivity analysis of theirobservables to the nuclear structure of the projectile, described within a halo effectivefield theory. In particular, I study the influence onto the cross sections of the ground-statewave function, the presence of subthreshold bound states and resonances. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20914号 / 理博第4366号 / 新制||理||1626(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 國廣 悌二, 教授 川合 光, 教授 永江 知文 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Il y a longtemps qu’on a attribué à l’hippocampe un rôle central dans la mémoire, mais ce n’est pas son unique rôle. Un nombre grandissant d’études attestent que l’hippocampe peut être séparé en deux régions, dorsale et ventrale, qui sont fonctionnellement différentes. La partie dorsale de l’hippocampe est responsable du rôle classique dans la mémoire spatiale et contextuelle, alors que la région ventrale de l’hippocampe est importante dans l’expression de l’anxiété et de la motivation, entre autres. Les projections des noyaux du raphé, l’unique source d’afférences sérotoninergiques de l’hippocampe, auraient un rôle régulateur sur ses fonctions, dont le comportement anxieux. Toutefois, les fonctions de la projection sérotoninergique raphé-hippocampe ventral ne sont pas entièrement caractérisées et les différents rôles des sous-populations de neurones sérotoninergiques au sein même de la projection raphé-hippocampe ventral sont peu connus. Dans ce projet de recherche, nous avons utilisé des tests comportementaux et des outils optogénétiques, afin de déterminer le rôle de la projection sérotoninergique raphé-hippocampe ventral dans le comportement d’aversion. Notre hypothèse est que la sérotonine régule l’anxiété en agissant sur l’hippocampe ventral via cette projection. Nous démontrons entre autres que l’activation de la projection sérotoninergique raphé-hippocampe ventral induit une hausse de l’anxiété, mais spécifiquement chez les femelles. Nous démontrons aussi que l’activation de la projection réduit la locomotion. Nos données offrent un nouveau point de vue sur le rôle du raphé médian dans l’anxiété ainsi que sur l’importance du sexe dans l’expression du comportement anxieux. / It has been known for a long time that the hippocampus has a central role in memory, but it isn’t its sole function. A growing number of studies are showing that the hippocampus can be split in two regions, dorsal and ventral, that are functionally different. The dorsal part is responsible for the classic and well-known role of the hippocampus in spatial and contextual memory, while the ventral region is important for the expression of anxiety and motivation, among other roles. The only serotonergic input of the hippocampus are the raphe nuclei and it has been suggested that it has a regulatory effect over its functions, such as anxiety. Nonetheless, the functions of the raphe-ventral hippocampus serotonergic projection are not fully characterized and sub-populations of serotonergic neurons inside the projection itself aren’t known. In this research project, we used behavioral tests and optogenetic tools to determine whether the raphe to ventral hippocampus serotonergic projection is able to influence aversive behaviors. Our hypothesis is that serotonin regulates anxiety through its influence on the ventral hippocampus via the raphe-ventral hippocampus serotonergic projection. We found that optogenetic activation of the projection induces heightened anxiety, but only in female mice. Our data offer new insight as to how the median raphe regulates anxiety and the importance of sex in the expression of anxiety.

Abstract Aerosol-cloud and aerosol-radiation interactions depend on several factors such as the physico-chemical properties, geographical and temporal variability, and vertical distribution of atmospheric aerosols. Of particular importance are cloud condensation nuclei (CCN) and black carbon (BC) particles as a subset of the atmospheric aerosol population. CCN are a prerequisite for cloud droplet formation, and variations in CCN loading can modify cloud properties. BC can efficiently absorb solar radiation, induce local heating and inhibit cloud formation. In order to determine the effects of CCN and BC on clouds, precipitation, radiation and the Earth’s energy budget, atmospheric loading and spatio-temporal distribution of aerosols are highly relevant. Thus this dissertation addresses and helps to elucidate the spatio-temporal variation and co-variability of CCN and BC with extensive field measurement data from aircraft and ground-based measurements. The data analyses focus on anthropogenic pollution, wildfire emissions and volcanic aerosols. In the Anthropocene, the distribution and abundance of atmospheric aerosols have changed drastically. Major sources of anthropogenic particulate pollution are the combustion of fossil fuels and biofuels as well as emissions from open biomass burning. The ubiquitous presence of anthropogenic air pollution, especially over continental regions in the Northern Hemisphere, hampers the assessment of anthropogenic influence on aerosol and climate due to a lack of unperturbed reference measurements. The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions that allowed us to investigate and quantify changes in the tropospheric composition in response to changes in anthropogenic emissions. The results reflect a strong and immediate influence of human activities on air quality, the role of BC as a major air pollutant in the Anthropocene, and close links between the atmospheric burdens of CCN and BC. Measurement data from five aircraft missions in polluted environments reveal characteristic relationships between CCN and BC in urban haze from Europe and East Asia, highly aged biomass burning smoke over the tropical Atlantic and the Amazon rainforest, and lightly aged biomass burning smoke over Europe, Brazil, and Asia. Over Europe and Asia, the vertical distribution of CCN in the lower troposphere up to altitudes about 5 km is highly sensitive to regional anthropogenic emissions. Over the tropical Atlantic ocean, the vertical distribution is strongly influenced by the longrange transport of mineral dust and biomass burning smoke, but volcanic eruptions also contribute to the aerosol load.

Aerosol-cloud interactions are the most uncertain component of the anthropogenic radiative forcing. A substantial part of this uncertainty comes from the limitations of currently used spaceborne CCN proxies that (i) are column integrated and do not guarantee vertical co-location of aerosols and clouds, (ii) have retrieval issues over land, and (iii) do not account for aerosol hygroscopicity. A possible solution to overcome these limitations is to use height-resolved measurements of the spaceborne lidar aboard the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite. This thesis presents a novel CCN retrieval algorithm based on Optical Modelling of CALIPSO Aerosol Microphysics (OMCAM) that is designed particularly for CALIPSO lidar measurements, along with its validation with airborne and surface in-situ measurements. \noindent OMCAM uses a set of normalized size distributions from the CALIPSO aerosol model and modifies them to reproduce the CALIPSO measured aerosol extinction coefficient. It then uses the modified size distribution and aerosol type-specific CCN parameterizations to estimate the number concentration of CCN (nCCN) at different supersaturations. The algorithm accounts for aerosol hygroscopicity by using the kappa parametrization. Sensitivity studies suggest that the uncertainty associated with the output nCCN may range between a factor of 2 and 3. OMCAM-estimated aerosol number concentrations (ANCs) and nCCN are validated using temporally and spatially co-located in-situ measurements. In the first part of validation, the airborne observations collected during the Atmospheric Tomography (ATom) mission are used. It is found that the OMCAM estimates of ANCs are in good agreement with the in-situ measurements with a correlation coefficient of 0.82, an RMSE of 247.2 cm-3, and a bias of 44.4 cm-3. The agreement holds for all aerosol types, except for marine aerosols, in which the OMCAM estimates are about an order of magnitude smaller than the in-situ measurements. An update of the marine model in OMCAM improve the agreement significantly. In the second part of validation, the OMCAM-estimated ANC and nCCN are compared to measurements from seven surface in-situ stations covering a variety of aerosol environments. The OMCAM-estimated monthly nCCN are found to be in reasonable agreement with the in-situ measurements with a 39 % normalized mean bias and 71 % normalized mean error. Combining the validation studies, the algorithm outputs are found to be consistent with the co-located in-situ measurements at different altitude ranges over both land and ocean. Such an agreement has not yet been achieved for spaceborne-derived CCN concentrations and demonstrates the potential of using CALIPSO lidar measurements for inferring global 3D climatologies of CCN concentrations related to different aerosol types.:1 Introduction . . . . . . . . . . . . . . . 1 1.1 Background: Aerosols in the climate system . . . . . . . . . . . . . . . . . 1 1.1.1 Aerosol-induced effective radiative forcing . . . . . . . . . . . . . . 3 1.1.2 Significance of aerosol-cloud interactions . . . . . . . . . . . . . . . 3 1.2 Observation-based ACI studies . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2.1 In-situ studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2.2 Spaceborne studies . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Spaceborne CCN proxies and their limitations . . . . . . . . . . . . . . . . 8 1.4 CCN concentrations from lidars . . . . . . . . . . . . . . . . . . . . . . . . 10 1.5 Objective: CCN from spaceborne lidar . . . . . . . . . . . . . . . . . . . . 11 2 Paper 1: Estimating cloud condensation nuclei concentrations from CALIPSO lidar measurements . . . . . . . . . . . . . . . 15 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.2 Data and retrievals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.2.1 CALIPSO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.2.2 MOPSMAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2.3 POLIPHON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.3 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.3.1 Aerosol size distribution . . . . . . . . . . . . . . . . . . . . . . . . 20 2.3.2 Aerosol hygroscopicity . . . . . . . . . . . . . . . . . . . . . . . . . 23 2.3.3 CCN parameterizations . . . . . . . . . . . . . . . . . . . . . . . . 23 2.3.4 Application of OMCAM to CALIPSO retrieval . . . . . . . . . . . 23 2.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.4.1 Sensitivity analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.4.2 Comparison with POLIPHON . . . . . . . . . . . . . . . . . . . . . 30 2.4.3 Case study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.5 Summary and conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 3 Paper 2: Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements . . . . . . . . . . . . . . . 39 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3.2 Data, retrievals, and methods . . . . . . . . . . . . . . . . . . . . . . . . . 42 3.2.1 ATom 3.2.2 CALIOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 3.2.3 Aerosol number concentration from CALIOP . . . . . . . . . . . . 44 3.2.4 Data matching and comparison . . . . . . . . . . . . . . . . . . . . 48 3.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 3.3.1 Example cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 3.3.2 General findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3.4 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 3.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 3.6 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 4 Paper 3: Assessment of CALIOP-derived CCN concentrations by in situ surface measurements . . . . . . . . . . . . . . . 65 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.2 Data and methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 4.2.1 In situ observations . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 4.2.2 CALIOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 4.2.3 Comparison Methodology . . . . . . . . . . . . . . . . . . . . . . . 71 4.3 Comparison of CCN Concentrations . . . . . . . . . . . . . . . . . . . . . . 73 4.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 5 Summary and conclusions . . . . . . . . . . . . . . . 79 6 Outlook . . . . . . . . . . . . . . . 83 References . . . . . . . . . . . . . . . 88 List of Abbreviations . . . . . . . . . . . . . . . 107 List of Variables . . . . . . . . . . . . . . . 109 List of Figures . . . . . . . . . . . . . . . 111 List of Tables . . . . . . . . . . . . . . . 113 A List of Publications . . . . . . . . . . . . . . . 115 B Acknowledgements . . . . . . . . . . . . . . . 117