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Tracing the Perseus Spiral Arm in the Anticenter Direction Tracing the Perseus spiral arm in the anticenter direction Maria Monguió i Montells ADVERTIMENT. La consulta d’aquesta tesi queda condicionada a l’acceptació de les següents condicions d'ús: La difusió d’aquesta tesi per mitjà del servei TDX (www.tdx.cat) i a través del Dipòsit Digital de la UB (diposit.ub.edu) ha estat autoritzada pels titulars dels drets de propietat intel·lectual únicament per a usos privats emmarcats en activitats d’investigació i docència. No s’autoritza la seva reproducció amb finalitats de lucre ni la seva difusió i posada a disposició des d’un lloc aliè al servei TDX ni al Dipòsit Digital de la UB. No s’autoritza la presentació del seu contingut en una finestra o marc aliè a TDX o al Dipòsit Digital de la UB (framing). Aquesta reserva de drets afecta tant al resum de presentació de la tesi com als seus continguts. En la utilització o cita de parts de la tesi és obligat indicar el nom de la persona autora. ADVERTENCIA. La consulta de esta tesis queda condicionada a la aceptación de las siguientes condiciones de uso: La difusión de esta tesis por medio del servicio TDR (www.tdx.cat) y a través del Repositorio Digital de la UB (diposit.ub.edu) ha sido autorizada por los titulares de los derechos de propiedad intelectual únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con finalidades de lucro ni su difusión y puesta a disposición desde un sitio ajeno al servicio TDR o al Repositorio Digital de la UB. No se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR o al Repositorio Digital de la UB (framing). Esta reserva de derechos afecta tanto al resumen de presentación de la tesis como a sus contenidos. En la utilización o cita de partes de la tesis es obligado indicar el nombre de la persona autora. WARNING. On having consulted this thesis you’re accepting the following use conditions: Spreading this thesis by the TDX (www.tdx.cat) service and by the UB Digital Repository (diposit.ub.edu) has been authorized by the titular of the intellectual property rights only for private uses placed in investigation and teaching activities. Reproduction with lucrative aims is not authorized nor its spreading and availability from a site foreign to the TDX service or to the UB Digital Repository. Introducing its content in a window or frame foreign to the TDX service or to the UB Digital Repository is not authorized (framing). Those rights affect to the presentation summary of the thesis as well as to its contents. In the using or citation of parts of the thesis it’s obliged to indicate the name of the author. Universitat de Barcelona Departament d’Astronomia i Meteorologia Tracing the Perseus spiral arm in the anticenter direction Mem`oria presentada per Maria Mongui´o i Montells per optar al grau de Doctor per la Universitat de Barcelona Barcelona, Setembre de 2013 2 . 3 ProgramadedoctoratenF´ısica Mem`oria presentada per Maria Mongui´o i Montells per optar al grau de Doctor per la Universitat de Barcelona Directors de la tesi: Dra. Francesca Figueras Dr. Preben Grosbøl Tutora de la tesi: Dra. Francesca Figueras 4 . 5 res “La gent t´e estrelles que no s´on iguals. Per uns, els que viatgen, les estrelles s´on guies. Per altres nom´es s´on llumets. Per altres, que s´on savis, s´on problemes. Per`ototes aquestes estrelles callen. Tu tindr`as estrelles com no en t´ening´u.” El petit pr´ıncep, Antoine de Saint-Exup´ery. “All men have the stars, but they are not the same things for different people. For some, who are travelers, the stars are guides. For others they are no more than little lights in the sky. For others, who are scholars, they are problems. But all these stars are silent. You -you alone- will have the stars as no one else has them.” The little prince, Antoine de Saint-Exup´ery. 6 . Acknowledgments / Agra¨ıments I would like to thank Dra. Francesca Figueras Si˜nol and Dr. Preben Grosbøl, for giving me the oportunity to develop this thesis. For everything they taught me, all the things we’ve learned together, all their support, and all the moments in the offices in Barcelona, in Garching, and also in some telescope control room. Cesca, merci per les hores, les correccions, les bromes, la paci`encia, els caf`es, i tantes i tantes coses... Mil gr`acies! Preben, thank you for not only telling and showing, but also involving me. Tak! Tamb´e vull agrair el suport de l’equip Gaia, encap¸calat pel Dr. Jordi Torra, la Dra. Carme Jordi i el Dr. Xavi Luri. A la Lola (Dra. Balaguer-N´u˜nez), per tot el suport cient´ıfic, log´ıstic i moral; al Dani per totes les re-instal·lacions; aix´ı com a la resta de cient´ıfics i enginyers del grup. Gr`acies a l’IEEC, a l’ICC i al Departament d’Astronomia i Meteorologia de la Universitat de Barcelona, aix´ı com a tots els seus membres. I especialment al JR, al Jordi, la Montse, la Rosa i al Gaby: espero haver-vos emprenyat una mica, per`o no massa. Thanks to the European Southern Observatory, for all the nice stays I have done both, in Garching and in Santiago de Chile, y especialmente al Dr. Giovanni Carraro. A la Teresa, la Merc`e, la Maria, el Santi, la Hoda i la Laia; gr`acies per compartir ci`encia, caipirinyes, simulacions, viatges, programes fortran, en python, i tot el que s’ha necessitat. A la colla de doctorants del DAM, per haver pogut compartir penes i alegries durant tots aquests anys. A la Laura, per compartir cam´ı(iperqu`e no importa les raons que tu tinguis, ella sempre guanya). A la Rosa i la Neus per les confid`encies (i la carros!). Al Pere, al Jordi, a l’H´ector, al Javi, al Pau, a la Carme, a la Gemma, al Sinu, al V´ıctor, al Josep Maria, a l’Alvaro, al Xavi, al Benito, (i als que em deixo!) perqu`e segons diu l’anunci, he passat amb vosaltres totes les diminutes vacances (o els petits caps de setmana) de cada dia, durant elsultims ´ cinc anys. Als amics de fora de l’astronomia. Als de Quanca per les nits estrellades als Pirineus. Als de futbol per permetre’m desconnectar. Per confondre’m amb una astr`ologa, preguntar-me pels extraterrestres, els salts del Baumgartner i els forats negres. Per tractar-me de friqui quan apuntant amunt asseguro que aquell punt ´es Saturn, i alhora flipar amb el l`aser i el telescopi. Isobretotalamevafam´ılia. Als meus pares, per ser-hi sempre. Al Pere, per tot el que n’aprenc i tot el que em fa enrabiar. A lesavies ` perqu`emelesestimomolt´ıssim. Als cosinets figueros d’aqu´ı i de per tot arreu, per les cerveses, els partits del Bar¸ca, les esquiades, i els minifigos, que s´on tots per menjar-te’ls! 7 8 This work was supported by the FPI grant (BES-2008-002471 through ESP2006-13855-C02- 01 project) of Miniterio de Ciencia y Educaci´on and the Spanish Ministry of Economy MINECO - FEDER through grants AYA2009-14648-C02-01, AYA2010-12176-E, AYA2012-39551-C02-01 and CONSOLIDER CSD2007-00050. The results of this work are based on observations made with the ING telescopes operated on the island of La Palma at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, and with the 1.5m tele- scope of the German Spanish Astronomical Center, Calar Alto, operated jointly by the Max Planck Institut fur Astronomie and the Instituto de Astrof´ısica de Andaluc´ıa. This research has made use of Aladin, Vizier and Simbad, developed by CDS, Strasbourg, France; TOPCAT & STILTS: Starlink Table/VOTable Processing Software developed by M.B. Taylor, and the WEBDA database, operated at the Department of Theoretical Physics and Astrophysics of the Masaryk University. During this thesis several visits to the Europen Southern Observatory have been done, both in Garching (Germany) and Santiago (Chile). We also want to thank Dr. Maria Czekaj and Dr. Annie Robin for providing us simulations of the new version of the Besan¸con Galaxy Model. Resum La nostra Gal`axia ´es un sistema d’unes 1011 estrelles, gas interestel·lar i petites quantitats de pols, on tamb´e hi podem trobar camps magn`etics a trav´es dels quals hi viatgen part´ıcules de rajos c`osmics. Tot i aix`o, s´on les forces gravitacionals les que governen l’estructura i la cinem`atica del sistema. Superposat a tota aquesta distribuci´o hi podem trobar l’estructura espiral, que tot i estar distribu¨ıdaatrav´es de tota la Gal`axia, tamb´e consta de petites agrupacions i irregularitats. Han passat m´es de 150 anys des que William Parsons (1800-1867) va detectar, l’any 1845, l’estructura espiral de M51. No obstant, no va ser fins l’any 1952 que W.W. Morgan va trobar, per primera vegada, evid`encies de l’estructura espiral a la Via L`actia, a trav´es d’observacions de regions d’hidrogen ionitzat, tot obtenint les seves dist`ancies a partir de paralaxis espec- trosc`opiques. Avui en dia, i despr´es de molts anys d’investigaci´o, encara no disposem d’una teoria completa sobre la forma i l’origen dels patrons espirals de la Via L`actia.
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