66 research outputs found
Subsidies for technology adoption : Experimental evidence from rural Cameroon
No full textWe use a two-stage experiment to study how a short-term subsidy for a new product affects uptake, usage, and future demand for the same product (a new solar lamp). We use an auction design to gauge willingness-to-pay, and randomly vary the strike price across villages to create random variation in purchase prices and uptake across villages. Our main results are that subsidies do not adversely affect subsequent product use, but stimulate uptake. If subsidies depress future willingness-to-pay, then this effect is outweighed by additional learning about the benefits of the new product. The net effect is that short-term subsidies increase future willingness-to-pay. However; prices play an important allocative role, and lowering prices via subsidies encourages uptake by households with low use intensity. We do not find any evidence supporting social learning and anchoring beyond the initial sample of beneficiaries
Conflito civil e liberdade no pensamento republicano de maquiavel
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Filosofia, Florianópolis, 2015Nosso propósito é refletir as condições da liberdade partindo da teoria do conflito civil em Maquiavel. Para cumprir essa finalidade, analisamos dois segmentos sociais que se confrontam em toda cidade, os grandes e o povo (grandi e plebe), aos quais correspondem dois humores (umori) de característica heterogênea: os grandes que desejam dominar o povo e o do povo que deseja unicamente viver em liberdade. Desse natural e ineliminável conflito, Maquiavel concebe as relações sociais em dissenso, ligeiramente distanciadas da concordia ordinum. Há, com esse pressuposto, uma relativa igualdade política na dinâmica do próprio enfrentamento desses humores que, ao serem acolhidos e recriados pelas instituições republicanas, se traduzem em leis e liberdade que beneficiam o conjunto da cidade. A teoria do conflito civil, ao esboçar certa autonomia em relação ao modelo polibiano da anacyclosis, ainda muito reproduzida pela tradição do pensamento político, acaba positivando o desejo do povo - ao lado do humor dos grandes - gerando reações aristocráticas diante de um presumível republicanismo popular do autor - Francesco Guicciardini confirma essa perspectiva. O desafio está em compreender que aspectos efetivamente concorrem nesse processo que vai, desde a anulação do bom e positivo conflito civil, para um convívio determinado por relações de subordinação e servidão (vivere servo). Mobilizando alguns capítulos centrais dos Discursos sobre a primeira década de Tito Lívio e de História de Florença - mas não sem remissões pontuais a outras obras do autor que subsidiem a discussão -, mostramos que a demanda por ações extraordinárias (straordinari) em situações de repúblicas corrompidíssimas, se deve à ingerência de relações desiguais e facciosas entre os distintos segmentos. À desigualdade nessas relações, atribui-se relativa inflexão do conteúdo político dos humores em direção a aspectos e fenômenos de natureza econômica. Trata-se de mostrar, em Maquiavel, que o próprio núcleo da teoria do conflito civil é permeado por uma clivagem social e econômica que sugere uma medida mais flexível de leitura de sua própria teoria do conflito civil e da liberdade.Abstract: Our purpose is to reflect the conditions of liberty based on the theory of civil conflict in Machiavelli. To accomplish this purpose, we analyzed two social sectors which are faced in every city, the big ones and the people (grandi and plebs), that correspond to two moods (umori) of heterogeneous feature: the big ones that wish to master the people and the people who only want to live in liberty. From this natural and non-eliminable conflict, Machiavelli conceives social relations in dissent, slightly away from concordia ordinum. There is, with this assumption, a relative political equality in the dynamics of the own confrontation of these moods that, when received and recreated by republican institutions, are translated into laws and liberty that benefit the entire city. The civil conflict theory, when showing certain autonomy from the Polybian model of anacyclosis, still very reproduced by the tradition of political thought, ended up achieving the will of the people - next to the big ones mood - generating aristocratic reactions to a presumable republicanism popular of the author - Francesco Guicciardini confirms this perspective. The challenge is to understand what aspects effectively compete in this process which is, since the abolishment of good and positive civil conflict, to a coexistence determined by relations of subordination and servitude (vivere servo). Mobilizing some central chapters of Discourses on Titus Livy's first ten books [Discorsi sopra la prima deca di Tito Livio] and Florentine Histories [Istorie Fiorentine] - but not without occasional references to other works of the author who subsidize the discussion - we showed that the demand for extraordinary actions (straordinari) in situations of corrupted republics, is due to the interference of unequal and unfair relations between different segments. To the inequality in these relations is attributed inflection of the political content of moods toward aspects and phenomena of an economic nature. This is to show, in Machiavelli, that the core of the civil conflict theory is permeated by a social and economic cleavage suggesting a more flexible measure of reading his own theory of civil conflict and liberty
X-Ray Polarization Detection of the Pulsar Wind Nebula in G21.5-0.9 with IXPE
No full textDi Lalla, Niccolò et al.-- Full list of authors: Di Lalla, Niccolò; Omodei, Nicola; Bucciantini, Niccolò; Dinsmore, Jack T.; Cibrario, Nicolò; Silvestri, Stefano; Wong, Josephine; Slane, Patrick; Mizuno, Tsunefumi; Negro, Michela; Romani, Roger W.; Ferrazzoli, Riccardo; Ng, C. -Y.; Michailidis, Miltiadis; Yang, Yi-Jung; Xie, Fei; Weisskopf, Martin C.; Kaaret, Philip; Agudo, Iván; Antonelli, Lucio A.; Bachetti, Matteo; Baldini, Luca; Baumgartner, Wayne H.; Bellazzini, Ronaldo; Bianchi, Stefano; Bongiorno, Stephen D.; Bonino, Raffaella; Brez, Alessandro; Capitanio, Fiamma; Castellano, Simone; Cavazzuti, Elisabetta; Chen, Chien-Ting; Ciprini, Stefano; Costa, Enrico; De Rosa, Alessandra; Del Monte, Ettore; Di Gesu, Laura; Di Marco, Alessandro; Donnarumma, Immacolata; Doroshenko, Victor; Dovčiak, Michal; Ehlert, Steven R.; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; Garcia, Javier A.; Gunji, Shuichi; Heyl, Jeremy; Iwakiri, Wataru; Jorstad, Svetlana G.; Karas, Vladimir; Kislat, Fabian; Kitaguchi, Takao; Kolodziejczak, Jeffery J.; Krawczynski, Henric; La Monaca, Fabio; Latronico, Luca; Liodakis, Ioannis; Maldera, Simone; Manfreda, Alberto; Marin, Frédéric; Marinucci, Andrea; Marscher, Alan P.; Marshall, Herman L.; Massaro, Francesco; Matt, Giorgio; Mitsuishi, Ikuyuki; Muleri, Fabio; O'Dell, Stephen L.; Oppedisano, Chiara; Papitto, Alessandro; Pavlov, George G.; Peirson, Abel Lawrence; Perri, Matteo; Pesce-Rollins, Melissa; Petrucci, Pierre-Olivier; Pilia, Maura; Possenti, Andrea; Poutanen, Juri; Puccetti, Simonetta; Ramsey, Brian D.; Rankin, John; Ratheesh, Ajay; Roberts, Oliver J.; Sgró, Carmelo; Soffitta, Paolo; Spandre, Gloria; Swartz, Douglas A.; Tamagawa, Toru; Tavecchio, Fabrizio; Taverna, Roberto; Tawara, Yuzuru; Tennant, Allyn F.; Thomas, Nicholas E.; Tombesi, Francesco; Trois, Alessio; Tsygankov, Sergey; Turolla, Roberto; Vink, Jacco; Wu, Kinwah; Zane, SilviaWe present the X-ray polarization observation of G21.5−0.9, a young Galactic supernova remnant (SNR), conducted with the Imaging X-ray Polarimetry Explorer (IXPE) in 2023 October, with a total livetime of approximately 837 ks. Using different analysis methods, such as a space-integrated study of the entire region of the pulsar wind nebula (PWN) and a space-resolved polarization map, we detect significant polarization from the PWN at the center of the SNR, with an average polarization degree of ∼10% oriented at ∼33° (north through east). No significant energy-dependent variation in polarization is observed across the IXPE band (2–8 keV). The polarization map, corrected for the effect of polarization leakage, reveals a consistent pattern in both degree and angle, with little change across the nebula. Our findings indicate the presence of a highly polarized central torus, suggesting low levels of turbulence at particle acceleration sites. Unlike Vela, but similar to the Crab Nebula, we observe substantial differences between radio and X-ray polarization maps. This suggests a clear separation in energy of the emitting particle populations and hints at an important, yet poorly understood, role of instabilities in the turbulence dynamics of PWNe. © 2025. The Author(s).The Imaging X-ray Polarimetry Explorer (IXPE) is a joint
US and Italian mission. The US contribution is supported by
the National Aeronautics and Space Administration (NASA)
and led and managed by its Marshall Space Flight Center
(MSFC), with industry partner Ball Aerospace (contract
NNM15AA18C). The Italian contribution is supported by the
Italian Space Agency (Agenzia Spaziale Italiana, ASI) through
contract ASI-OHBI-2022-13-I.0, agreements ASI-INAF-2022-
19-HH.0 and ASI-INFN-2017.13-H0, and its Space Science
Data Center (SSDC) with agreements ASI-INAF-2022-14-
HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto
Nazionale di Astrofisica (INAF) and the Istituto Nazionale di
Fisica Nucleare (INFN) in Italy. This research used data
products provided by the IXPE Team (MSFC, SSDC, INAF,
and INFN) and distributed with additional software tools by
the High-Energy Astrophysics Science Archive Research
Center (HEASARC), at NASA Goddard Space Flight Center
(GSFC). R.F., E.Co., A.D.M., S.F., F.L.M., F.Mu., and P.So.
are partially supported by MAECI with grant CN24GR08
“GRBAXP: Guangxi Rome Bilateral Agreement for X-ray
Polarimetry in Astrophysics.” C.-Y.N. is supported by a GRF
grant of the Hong Kong Government under HKU 17304524.
N.B. was supported by the INAF MiniGrant “PWNnumpol—
Numerical Studies of Pulsar Wind Nebulae in The Light of
IXPE.” F.X. is supported by National Natural Science
Foundation of China (grant Nos. 12373041 and 12422306),
and Bagui Scholars Program (XF). I.L. was funded by the
European Union ERC-2022-STG – BOOTES – 101076343.
Views and opinions expressed are however those of the author
(s) only and do not necessarily reflect those of the European
Union or the European Research Council Executive Agency.
Neither the European Union nor the granting authority can be
held responsible for them.Peer reviewe
The first Neolithic boats in the Mediterranean: The settlement of La Marmotta (Anguillara Sabazia, Lazio, Italy)
No full text© 2024 Gibaja et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Navigation in the Mediterranean in the Neolithic is studied here through the boats that were used, the degree of technical specialisation in their construction and, above all, their chronology. After a brief explanation of the exceptional site of La Marmotta, the characteristics and chronology of the five canoes found at the settlement and one of the nautical objects linked to Canoe 1 are discussed. This will allow a reflection on the capability of Neolithic societies for navigation owing to their high technological level. This technology was an essential part in the success of their expansion, bearing in mind that in a few millennia they occupied the whole Mediterranean from Cyprus to the Atlantic seaboard of the Iberian Peninsula.The research has been carried out in the collaboration agreement between the Museo delle Civiltà and the Spanish Scientific Research Council (centres in Barcelona IMF-CSIC and Rome EEHAR-CSIC) and the National Accelerators Centre (CNA) in Seville. Several projects have resulted from this collaboration funded by the Ministry of Science and Innovation and State Research Agency of Spain, Marie Curie Europe Program, JdC-Formación 2020 AEI Program, and Ministry for University and Research of Italy: PID2020-112513RB-I00/AEI/10.13039/501100011033, HAR2016-75201-P, PIAR-201818008, PIAR-201918010, QUANT-792544, PICT-2015-2541 and Rita Levi Montalcini project ‘AGER’.Peer reviewe
Participation, Legitimacy and Fiscal Capacity in Weak States: Evidence from Participatory Budgeting
No full textThis paper is jointly published by the Centre for the Study of African Economies (CSAE) at the University of Oxford and the Local Government Revenue Initiative (LoGRI) at the University of Toronto. Identical versions appear in both institutions’ working paper series.Building durable fiscal capacity requires that states obtain compliance with their taxes—a persistent challenge for states with low enforcement capacity. One promising option for governments in weak states is to raise voluntary compliance by enhancing governmental legitimacy. This study reports results from a participatory budgeting policy experiment in Sierra Leone designed to increase legitimacy and tax compliance by inviting public participation in local policy decision-making. In phone-based town halls, participants shared policy preferences with neighbors and local politicians and then voted for public services that were subsequently implemented. We find that the intervention durably increased participants’ perceptions of government legitimacy. However, contrary to influential models of tax compliance, we report a robust null effect on tax compliance behavior. Participants’ partisan affiliation strongly conditions the treatments’ effects on tax compliance and attitudes toward paying taxes: We find large, positive impacts among copartisans of the incumbent government but significant negative impacts among non-copartisans. Our results highlight that the legitimacy gains of participatory interventions may not increase voluntary tax compliance when participation politicizes compliance.International Growth Centre, International Centre for Tax and Development, Local Government Revenue Initiativ
List Niccola Perottiego, przekład zbiorowy pod redakcją Pauliny Piotrowskiej
No full textA letter by Niccolò Perotti This paper is dedicated to a letter that Niccolò Perotti wrote to a friend. It is divided into two parts. The first part is an introduction to the letter. It presents an autobiography of the Renaissance humanist with special emphasis placed on his translations of ancient Greek texts into Latin. Jean-Louis Charlet, the leading researcher on the Italian’s works, highlights the importance of this particular letter for establishing the chronology of translations and Perotti’s other works, as well as his date of birth and other major events in his life. The introduction also discusses the epistolary art, which Perotti practiced and whose grammatical rules he wrote down so he could study them. Next, the author considers the subject matter of the letter, which oscillates between the notions of vera nobilitas and homo novus. Perotti decides to give himself over to literary activities and he substantiates his choice in a form of examination of conscience. For him as a humanist, who often avails himself of quotes from Pliny the Younger, true nobility arises out of the virtues of reason and is not based on material goods. In his deliberations, Perotti follows such remarkable minds as Petrarch, Poggio Bracciolini and Buonaccorso da Montemagno. He quotes Petrarch on the magnitude of human thought, Bracciolini on the threats arising from the desire for wealth, and Montemagno on the true source of nobility lying in virtue and a person’s work, but not in the right of inheritance. Finally, these thoughts are collated with the Stoic philosophy of Epictetus. Having translated Encheiridion, Perotti filled his epistolary confessions with an echo of the Stoic’s teachings. These mostly concern taking care of one’s soul and not becoming attached to material goods, obtained by twist of fate. In the second part, the author presents a collective translation of the discussed letter, preserved in manuscript in the Vatican Library (Vat. lat. 3027, f.115r–f.118r). It is a very important autobiographical document that allows the reader to look upon Perotti’s work in the context of the popularization of ancient Greek thought, as well as to his motivations and the internal dilemmas that were entailed in this undertaking
Altered feeding behavior and immune competence in paper wasps: A case of parasite manipulation?
No full textPaper wasps (Polistes dominula), parasitized by the strepsipteran Xenos vesparum, are castrated and desert the colony to gather on plants where the parasite mates and releases primary larvae, thus completing its lifecycle. One of these plants is the trumpet creeper Campsis radicans: in a previous study the majority of all wasps collected from this plant were parasitized and focused their foraging activity on C. radicans buds. The unexpected prevalence and unusual feeding strategy prompted us to investigate the influence of this plant on wasp behavior and physiology through a multidisciplinary approach. First, in a series of laboratory bioassays, we observed that parasitized wasps spent more time than non-parasitized ones on fresh C. radicans buds, rich of extra-floral nectaries (EFNs), while the same wasps ignored treated buds that lacked nectar drops. Then, we described the structure and ultra-structure of EFNs secreting cells, compatible with the synthesis of phenolic compounds. Subsequently, we analysed extracts from different bud tissues by HPLC-DAD-MS and found that verbascoside was the most abundant bioactive molecule in those tissues rich in EFNs. Finally, we tested the immune-stimulant properties of verbascoside, as the biochemical nature of this compound indicates it might function as an antibacterial and antioxidant. We measured bacterial clearance in wasps, as a proxy for overall immune competence, and observed that it was enhanced after administration of verbascoside-even more so if the wasp was parasitized. We hypothesize that the parasite manipulates wasp behavior to preferentially feed on C. radicans EFNs, since the bioactive properties of verbascoside likely increase host survival and thus the parasite own fitness
X-Ray Polarization of the Eastern Lobe of SS 433
No full textKaaret, Philip et al.--Full list of authors: Kaaret, Philip; Ferrazzoli, Riccardo; Silvestri, Stefano; Negro, Michela; Manfreda, Alberto; Wu, Kinwah; Costa, Enrico; Soffitta, Paolo; Safi-Harb, Samar; Poutanen, Juri; Veledina, Alexandra; Di Marco, Alessandro; Slane, Patrick; Bianchi, Stefano; Ingram, Adam; Romani, Roger W.; Cibrario, Nicolò; Mac Intyre, Brydyn; Mikus̆incová, Romana; Ratheesh, Ajay; Steiner, James F.; Svoboda, Jiri; Tugliani, Stefano; Agudo, Iván; Antonelli, Lucio A.; Bachetti, Matteo; Baldini, Luca; Baumgartner, Wayne H.; Bellazzini, Ronaldo; Bongiorno, Stephen D.; Bonino, Raffaella; Brez, Alessandro; Bucciantini, Niccolò; Capitanio, Fiamma; Castellano, Simone; Cavazzuti, Elisabetta; Chen, Chien-Ting; Ciprini, Stefano; De Rosa, Alessandra; Del Monte, Ettore; Di Gesu, Laura; Di Lalla, Niccolò; Donnarumma, Immacolata; Doroshenko, Victor; Dovčiak, Michal; Ehlert, Steven R.; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; García, Javier A.; Gunji, Shuichi; Hayashida, Kiyoshi; Heyl, Jeremy; Iwakiri, Wataru; Jorstad, Svetlana G.; Karas, Vladimir; Kislat, Fabian; Kitaguchi, Takao; Kolodziejczak, Jeffery J.; Krawczynski, Henric; La Monaca, Fabio; Latronico, Luca; Liodakis, Ioannis; Maldera, Simone; Marin, Frédéric; Marinucci, Andrea; Marscher, Alan P.; Marshall, Herman L.; Massaro, Francesco; Matt, Giorgio; Mitsuishi, Ikuyuki; Mizuno, Tsunefumi; Muleri, Fabio; Ng, Chi-Yung; O'Dell, Stephen L.; Omodei, Nicola; Oppedisano, Chiara; Papitto, Alessandro; Pavlov, George G.; Peirson, Abel L.; Perri, Matteo; Pesce-Rollins, Melissa; Petrucci, Pierre-Olivier; Pilia, Maura; Possenti, Andrea; Puccetti, Simonetta; Ramsey, Brian D.; Rankin, John; Roberts, Oliver J.; Sgrò, Carmelo; Spandre, Gloria; Swartz, Douglas A.; Tamagawa, Toru; Tavecchio, Fabrizio; Taverna, Roberto; Tawara, Yuzuru; Tennant, Allyn F.; Thomas, Nicholas E.; Tombesi, Francesco; Trois, Alessio; Tsygankov, Sergey S.; Turolla, Roberto; Vink, Jacco; Weisskopf, Martin C.; Xie, Fei; Zane, SilviaHow astrophysical systems translate the kinetic energy of bulk motion into the acceleration of particles to very high energies is a pressing question. SS 433 is a microquasar that emits TeV γ-rays indicating the presence of high-energy particles. A region of hard X-ray emission in the eastern lobe of SS 433 was recently identified as an acceleration site. We observed this region with the Imaging X-ray Polarimetry Explorer and measured a polarization degree in the range 38%–77%. The high polarization degree indicates the magnetic field has a well-ordered component if the X-rays are due to synchrotron emission. The polarization angle is in the range −12° to +10° (east of north), which indicates that the magnetic field is parallel to the jet. Magnetic fields parallel to the bulk flow have also been found in supernova remnants and the jets of powerful radio galaxies. This may be caused by interaction of the flow with the ambient medium. © 2024. The Author(s). Published by the American Astronomical Society.The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. A.V. acknowledges support from the Academy of Finland grant 355672.Peer reviewe
Discovery of X-Ray Polarization from the Black Hole Transient Swift J1727.8-1613
No full textFull list of the authors: Veledina, Alexandra; Muleri, Fabio; Dovčiak, Michal; Poutanen, Juri; Ratheesh, Ajay; Capitanio, Fiamma; Matt, Giorgio; Soffitta, Paolo; Tennant, Allyn F.; Negro, Michela; Kaaret, Philip; Costa, Enrico; Ingram, Adam; Svoboda, Jiří; Krawczynski, Henric; Bianchi, Stefano; Steiner, James F.; García, Javier A.; Kravtsov, Vadim; Nitindala, Anagha P.; Ewing, Melissa; Mastroserio, Guglielmo; Marinucci, Andrea; Ursini, Francesco; Tombesi, Francesco; Tsygankov, Sergey S.; Yang, Yi-Jung; Weisskopf, Martin C.; Trushkin, Sergei A.; Egron, Elise; Iacolina, Maria Noemi; Pilia, Maura; Marra, Lorenzo; Mikušincová, Romana; Nathan, Edward; Parra, Maxime; Petrucci, Pierre-Olivier; Podgorný, Jakub; Tugliani, Stefano; Zane, Silvia; Zhang, Wenda; Agudo, Iván; Antonelli, Lucio A.; Bachetti, Matteo; Baldini, Luca; Baumgartner, Wayne H.; Bellazzini, Ronaldo; Bongiorno, Stephen D.; Bonino, Raffaella; Brez, Alessandro; Bucciantini, Niccolò; Castellano, Simone; Cavazzuti, Elisabetta; Chen, Chien-Ting; Ciprini, Stefano; De Rosa, Alessandra; Del Monte, Ettore; Di Gesu, Laura; Di Lalla, Niccolò; Di Marco, Alessandro; Donnarumma, Immacolata; Doroshenko, Victor; Ehlert, Steven R.; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; Ferrazzoli, Riccardo; Gunji, Shuichi; Hayashida, Kiyoshi; Heyl, Jeremy; Iwakiri, Wataru; Jorstad, Svetlana G.; Karas, Vladimir; Kislat, Fabian; Kitaguchi, Takao; Kolodziejczak, Jeffery J.; La Monaca, Fabio; Latronico, Luca; Liodakis, Ioannis; Maldera, Simone; Manfreda, Alberto; Marin, Frédéric; Marscher, Alan P.; Marshall, Herman L.; Massaro, Francesco; Mitsuishi, Ikuyuki; Mizuno, Tsunefumi; Ng, Chi-Yung; O'Dell, Stephen L.; Omodei, Nicola; Oppedisano, Chiara; Papitto, Alessandro; Pavlov, George G.; Peirson, Abel L.; Perri, Matteo; Pesce-Rollins, Melissa; Possenti, Andrea; Puccetti, Simonetta; Ramsey, Brian D.; Rankin, John; Roberts, Oliver J.; Romani, Roger W.; Sgrò, Carmelo; Slane, Patrick; Spandre, Gloria; Swartz, Douglas A.; Tamagawa, Toru; Tavecchio, Fabrizio; Taverna, Roberto; Tawara, Yuzuru; Thomas, Nicholas E.; Trois, Alessio; Turolla, Roberto; Vink, Jacco; Wu, Kinwah; Xie, FeiWe report the first detection of the X-ray polarization of the bright transient Swift J1727.8−1613 with the Imaging X-ray Polarimetry Explorer. The observation was performed at the beginning of the 2023 discovery outburst, when the source resided in the bright hard state. We find a time- and energy-averaged polarization degree of 4.1% ± 0.2% and a polarization angle of 2.°2 ± 1.°3 (errors at 68% confidence level; this translates to ∼20σ significance of the polarization detection). This finding suggests that the hot corona emitting the bulk of the detected X-rays is elongated, rather than spherical. The X-ray polarization angle is consistent with that found in submillimeter wavelengths. Since the submillimeter polarization was found to be aligned with the jet direction in other X-ray binaries, this indicates that the corona is elongated orthogonal to the jet. © 2023. The Author(s). Published by the American Astronomical Society.The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2022-13-I.0, agreements ASI-INAF-2022-19-HH.0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). This research has made use of the MAXI data provided by RIKEN, JAXA, and the MAXI team
Cristoforo Buondelmonti, Descriptio insule Crete. Edizione critica e introduzione
No full textLa tesi propone una nuova edizione critica della Descriptio insule Crete di Cristoforo Buondelmonti (1384-1430 ca.), che aggiorna e rivede profondamente l’edizione di Van Spitael (1981) sulla base di nuove acquisizioni. Preceduta da un’introduzione volta a indagare la peculiare metodologia dell’autore nella stesura della monografia su Creta, la nota al testo fornisce un’approfondita descrizione codicologica dei testimoni manoscritti e ne studia gli intricati rapporti di parentela. Il confronto serrato delle varianti d’autore ha inoltre condotto a una nuova ricostruzione dell’articolato iter redazionale, distinguibile in tre tappe: a una prima versione, nata sotto forma di resoconto personale all’amico Niccolò Niccoli dell’esplorazione cretese e tràdita dal manoscritto Laurenziano Pluteo 29.42, segue una versione più ampia, testimoniata dal Chigiano F. IV. 74 e dal codex deperditus ex-Baden, a sua volta superata da una terza e ultima redazione, tràdita dal Rossiano 703 e dal codice MS-G-13 di Düsseldorf (non considerato nella precedente edizione dell’opera), che costituiscono la base per il nuovo testo critico. Quest’ultimo è corredato da una doppia fascia di apparato, in cui si segnalano le varianti d’autore delle due precedenti redazioni e gli errori di tradizione. Cruciale si è rivelato proprio lo studio diacronico dei vari stadi evolutivi dell’opera, dal quale è emersa con chiarezza la volontà di Buondelmonti di sprovincializzare la propria relazione di viaggio, nata in un contesto squisitamente fiorentino, e rivestirla di un apparato letterario ed erudito più in linea con le rinnovate esigenze della stagione umanistica.
English version:
The thesis proposes a new scholarly edition of Descriptio insule Crete by Cristoforo Buondelmonti (ca. 1384-1430), which updates and deeply revises the edition by Van Spitael (1981) on the basis of new acquisitions. Preceded by an introduction aimed at investigating the peculiar methodology of the author in the writing the monograph about Crete, the Note to the Text provides a thorough codicological description of the manuscript witnesses and the study of their intricate relationships. The close comparison of the author’s variants has also led to a new reconstruction of the complex editorial process, distinguishable in three stages: a first version, born in the form of a personal report about the Cretan exploration to his friend Niccolò Niccoli and witnessed by the manuscript Laurenziano Pluteo 29.42, was followed by a larger version, witnessed by the Chigiano F. IV. 74 and by the codex deperditus ex-Baden, which was in turn superseded by a third and final version, witnessed by the Rossiano 703 and by the codex MS-G-13 of Düsseldorf (not considered by Van Spitael’s edition), which form the basis for the new scholarly edition. The latter is accompanied by a double band of apparatus, in which the author’s variants of the two previous versions and the errors of tradition are reported. The diachronic study of the various editorial phases of the work has been crucial, and it has clearly shown Buondelmonti’s will to de-provincialize his travel report, born in an exquisitely Florentine context, and to cover it with a literary and erudite stratum more in line with the needs of the humanistic season
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