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A comprehensive summary of the measurements made to characterize test-mass charging due to the space environment during the LISA Pathfinder mission is presented. Measurements of the residual charge of the test mass after release by the grabbing and positioning mechanism show that the initial charge of the test masses was negative after all releases, leaving the test mass with a potential in the range from -12 to -512. Variations in the neutral test-mass charging rate between 21.7 and 30.7 e s-1 were observed over the course of the 17-month science operations produced by cosmic ray flux changes including a Forbush decrease associated with a small solar energetic particle event. A dependence of the cosmic ray charging rate on the test-mass potential between -30.2 and -40.3 e s-1 V-1 was observed resulting in an equilibrium test-mass potential between 670 and 960 mV, and this is attributed to a contribution to charging from low-energy electrons emitted from the gold surfaces of the gravitational reference sensor. Data from the onboard particle detector show a reliable correlation with the charging rate and with other environmental monitors of the cosmic ray flux. This correlation is exploited to extrapolate test-mass charging rates to a 20-year period giving useful insight into the expected range of charging rate that may be observed in the LISA mission., Physical Review D, 107 (6), ISSN:1550-7998, ISSN:0556-2821, ISSN:1550-2368

Introduction Le problème du recours aux exceptions et aux dérogations à la législation existante, pour faire face à une situation de crise, est un thème nouveau dans les études médiévales italiennes. Les premières analyses ponctuelles sur la question, réalisées entre 2007 et 2010 par Giuliano Milani, Sara Menzinger et Lorenzo Tanzini, ont montré que cette pratique était largement répandue. Néanmoins, la possibilité d’une instabilité du système juridique en raison de l’utilisation persistante ...

À l’heure où les formes de la démocratie représentative sont interrogées de différentes manières, que peuvent nous apprendre les expériences de délibération communale développées au sein des communautés urbaines médiévales et modernes ? Les registres de délibérations forment un corpus très abondant depuis la fin du Moyen Âge. Leur production, en Europe méridionale puis occidentale, a accompagné le développement des formes écrites de l’administration. Or, à l’échelle du gouvernement des sociétés médiévales et modernes, les écritures des conseils de ville permettent de pénétrer les processus de la prise de décision. Les études ici contenues interrogent la diffusion et l’adaptation locale des cultures politiques européennes. Elles prolongent les avancées les plus récentes de la recherche sur le pouvoir de l’écrit, sur un terrain nouveau. Il s’agit ici de la première synthèse sur les sources historiques sans doute les plus abondantes et les plus continues en histoire urbaine. Apparemment banals, les registres de délibérations ont été jusque-là utilisés par les historiens sans y prêter toute l’attention qu’ils méritaient. Cet ouvrage mutualise les approches méthodologiques. Le collectif de chercheurs réunis forge ainsi les outils d’un comparatisme européen, à l’échelle urbaine. La perspective choisie est celle de la longue durée, en examinant l’évolution politique et scripturale des institutions municipales du XIIIe au XVIIIe siècle.

Il 1258 rappresenta uno snodo decisivo nella storia di Bologna: la città era una vera e propria potenza regionale, che si apprestava a raggiungere il pieno controllo sulla Romagna. Le ondate di maltempo causate dell’eruzione del vulcano Samalas però causarono una importante carestia che fu aggravata dal blocco commerciale imposto da Venezia, interessata a scalzare dalla regione i rivali bolognesi e ad acquisire la piena egemonia in Romagna. All’interno della città felsinea l’emergenza ebbe non poche ripercussioni politiche: fu soprattutto cavalcata dal popolo, che la sfruttò per conquistare maggiore potere all’interno dello spazio politico e per accreditarsi agli occhi della cittadinanza come l’unico soggetto in grado di perseguire il bene pubblico. Da questo conflitto nacquero gli Ordinamenta bladi, vale a dire la prima legislazione sistematica in materia annonaria che fu emanata proprio nel 1259, la cui analisi permette di comprendere entro quali limiti e con quali provvedimenti fu affrontata la carestia., The year 1258 represents a decisive junction in the history of Bologna: the city was a true regional power, which was preparing to achieve full control over Romagna. The waves of bad weather caused by the eruption of the Samalas volcano, however, caused an important famine that was aggravated by the commercial blockade imposed by Venice, interested in ousting its rivals from the region and acquiring full hegemony in Romagna. Within the city of Bologna, the emergency had many political repercussions: it was especially ridden by the people, who exploited it to gain more power within the political space and to accredit in the eyes of citizenship as the only subject able to pursue the public good. From this conflict were born the Ordinamenta bladi, that is the first systematic legislation on the subject of food that was issued in 1259, whose analysis allows to understand within what limits and with what measures the famine was addressed.

Following the selection of The Gravitational Universe by ESA, and the successful flight of LISA Pathfinder, the LISA Consortium now proposes a 4 year mission in response to ESA's call for missions for L3. The observatory will be based on three arms with six active laser links, between three identical spacecraft in a triangular formation separated by 2.5 million km. LISA is an all-sky monitor and will offer a wide view of a dynamic cosmos using Gravitational Waves as new and unique messengers to unveil The Gravitational Universe. It provides the closest ever view of the infant Universe at TeV energy scales, has known sources in the form of verification binaries in the Milky Way, and can probe the entire Universe, from its smallest scales near the horizons of black holes, all the way to cosmological scales. The LISA mission will scan the entire sky as it follows behind the Earth in its orbit, obtaining both polarisations of the Gravitational Waves simultaneously, and will measure source parameters with astrophysically relevant sensitivity in a band from below $10^{-4}\,$Hz to above $10^{-1}\,$Hz., Submitted to ESA on January 13th in response to the call for missions for the L3 slot in the Cosmic Vision Programme

Durante l’impegno politico di Dante, i rapporti tra Firenze e Bologna furono stretti e ben documentati. Tra 1296 e 1299, Bologna combatté contro il marchese d’Este e i Ghibellini di Romagna e Firenze fu prima alleata, poi mediatrice tra le parti su mandato di Bonifacio VIII. La documentazione bolognese svela sistemi di alleanze instabili e in continua riconfigurazione, influenzati dal pontefice e dalle parti delle città. Il linguaggio della documentazione mostra anche come i termini di “Guelfo” e “Ghibellino” furono relativizzati e utilizzati per identificare gli amici e i nemici., Reti Medievali Rivista, Vol 18, No 1 (2017): Forthcoming

We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2 ± 0.1 fm s(−2)/√Hz, or (0.54 ± 0.01) × 10(−15) g/√Hz, with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8 ± 0.3) fm / √Hz, about 2 orders of magnitude better than requirements. At f ≤ 0.5 mHz we observe a low-frequency tail that stays below 12 fm s(−2)/√Hz down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA., Physical Review Letters, 116 (23), ISSN:0031-9007, ISSN:1079-7114