[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-135201-en":3,"doc-seo-135201-105":31,"detail-sidebar-cat-0-en-105":92},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":20,"is_deleted":4,"is_public":21,"is_downloadable":21,"audit_status":21,"page_count":22,"language":23,"language_code":24,"site_id":25,"html_lang":24,"table_of_contents":26,"faqs":27,"seo_title":28,"seo_description":14,"update_tm":29,"read_time":30},135201,1099525198933,"Terk","https://ap-avatar.wpscdn.com/davatar_155a257f0dc6eb9ab79c44ca47cae57d",8,"Research & Report","Modeling Asymmetry in the Rotation of Disk Galaxies - Doctor of Philosophy Thesis","This dissertation develops and applies kinematic-based modeling methods to study asymmetries in the rotation of disk galaxies, with emphasis on how gravitational lensing and nonaxisymmetric structures affect observed rotation and inferred parameters. A novel framework combines imaging and kinematics at moderate redshift to extract weak-lensing shear while tracking coordinate and velocity-field distortions. The work then quantifies bisymmetric mode strength in barred galaxies using MaNGA data and characterizes stellar population gradients in kinematically identified bars, linking dynamical modeling to stellar-population outcomes and assessing biases.","UC Santa Cruz  \nUC Santa Cruz Electronic Theses and Dissertations  \nTitle  \nModeling Asymmetry in the Rotation of Disk Galaxies  \nPermalink  \n[https://escholarship.org/uc/item/9rj786w1](https://escholarship.org/uc/item/9rj786w1)  \nAuthor  \nDiGiorgio, Brian Stephen  \nPublication Date  \n2023  \nPeer reviewed|Thesis/dissertation  \n[eScholarship.org](eScholarship.org) Powered by the California Digital Library  \nUniversity of California  \nUNIVERSITY OF CALIFORNIA  \nSANTA CRUZ  \nMODELING ASYMMETRY IN THE ROTATION OF DISK  \nGALAXIES  \nA dissertation submitted in partial satisfaction of the  \nrequirements for the degree of  \nDoctor of Philosophy  \nin  \nASTRONOMY AND ASTROPHYSICS  \nby  \nBrian DiGiorgio  \nJune 2023  \nThe Dissertation of Brian DiGiorgio is approved:  \n\n| Puragra GuhaThakurta, Chair |\n| --- |\n| Kevin Bundy |\n\nKyle B. Westfall  \nPeter Biehl  \nVice Provost and Dean of Graduate Studies  \nCopyright © by Brian DiGiorgio 2023  \nTable of Contents  \nList of Figures v  \nAbstract xiii  \nAcknowledgments xv  \nDedication xxi  \n1 Introduction 1  \n1.1 The Flattening of Galaxy Rotation Curves ................. 2  \n1.2 Modeling Disk Rotation ........................... 3  \n1.3 Modeling Nonaxisymmetric Disks ...................... 6  \n1.4 Outline of This Work ............................. 8  \n2 A Novel Framework for Modeling Weakly Lensing Shear Using Kinematics and Imaging at Moderate Redshift 10  \n2.1 Introduction .................................. 10  \n2.2 Weak Lensing Effects on Imaging ...................... 15  \n2.2.1 General Lensing Theory ....................... 16  \n2.2.2 Image Distortions .......................... 19  \n2.3 Weak Lensing Effects on Kinematics .................... 24  \n2.3.1 Kinematic Axis Distortion ...................... 25  \n2.3.2 Sheared Velocity Field Fitting ................... 27  \n2.4 Combining Imaging and Kinematics .................... 33  \n2.4.1 Kinematic and Photometric Position Angle Offset ........ 33  \n2.4.2 KWL Models with Imaging Information .............. 36  \n2.4.3 Survey Design Considerations .................... 41  \n2.5 Conclusion .................................. 49  \n3 The Strength of Bisymmetric Modes in SDSS-IV/MaNGA Barred Galaxy Kinematics 50  \n3.1 Introduction .................................. 50  \n3.2 MaNGA Data ................................. 54  \n3.2.1 MaNGA: Mapping Nearby Galaxies at Apache Point Observatory 54  \n3.2.2 Data Processing ........................... 56  \n3.2.3 Sample ................................ 58  \n3.2.4 Control Sample ............................ 60  \n3.3 Bisymmetric Kinematic Model ....................... 62  \n3.4 Fitting Algorithm ............................... 66  \n3.4.1 Priors ................................. 66  \n3.4.2 Likelihood ............................... 71  \n3.4.3 Example Results ........................... 74  \n3.5 Results ..................................... 80  \n3.5.1 Projection biases ........................... 80  \n3.5.2 Comparison with imaging ...................... 84  \n3.5.3 Velocity components ......................... 87  \n3.6 Summary ................................... 90  \n4 Characterizing Stellar Population Gradients in Kinematically-Identified Bars 92  \n4.1 Introduction .................................. 92  \n4.2 Data ...................................... 95  \n4.2.1 MaNGA: Mapping Nearby Galaxies at Apache Point Observatory 95  \n4.2.2 Nirvana: Nonaxisymmetric Irregular Rotational Velocity Analysis 97  \n4.2.3 Nirvana-MaNGA Sample ...................... 99  \n4.3 Nirvana Bar Regions ............................. 100  \n4.4 Stellar Population Gradients ......................... 103  \n4.5 Results ..................................... 105  \n4.6 Summary ................................... 108  \n5 Summary and Future Studies 110  \n5.1 Summary ................................... 110  \n5.2 Future Work ................................. 112  \n5.2.1 Effects of Bars on KWL Errors ................... 112  \n5.2.2 KWL Pilot Study ................","cbCaitEE0zMJI3qp","https://ap.wps.com/l/cbCaitEE0zMJI3qp","pdf",4165510,2,1,147,"English","en",105,"# Introduction\n## The Flattening of Galaxy Rotation Curves\n## Modeling Disk Rotation\n## Modeling Nonaxisymmetric Disks\n## Outline of This Work\n# A Novel Framework for Modeling Weakly Lensing Shear Using Kinematics and Imaging at Moderate Redshift\n## Weak Lensing Effects on Imaging\n## Weak Lensing Effects on Kinematics\n## Combining Imaging and Kinematics\n## Conclusion\n# The Strength of Bisymmetric Modes in SDSS-IV/MaNGA Barred Galaxy Kinematics\n## MaNGA Data\n## Bisymmetric Kinematic Model\n## Fitting Algorithm\n## Results\n# Characterizing Stellar Population Gradients in Kinematically-Identified Bars\n## Data\n## Nirvana Bar Regions\n## Stellar Population Gradients\n## Results\n# Summary and Future Studies\n## Summary\n## Future Work","[{\"question\":\"What is the main research focus of the dissertation?\",\"answer\":\"The dissertation focuses on modeling asymmetry in the rotation of disk galaxies and on how such asymmetries and observational effects influence kinematic inferences.\"},{\"question\":\"How does the work address weak gravitational lensing in galaxy rotation modeling?\",\"answer\":\"It introduces a framework that combines imaging and kinematics to extract weak-lensing shear, accounting for distortions to coordinate systems and velocity-field contours.\"},{\"question\":\"What datasets and analyses are used for barred galaxies?\",\"answer\":\"The dissertation uses SDSS-IV/MaNGA data to fit bisymmetric kinematic models, and it applies Nirvana-related analyses to characterize bar regions and associated stellar population gradients.\"}]","Modeling Asymmetry in the Rotation of Disk Galaxies - Doctor of Philosophy Thesis | PDF",1787307037,370,{"code":4,"msg":32,"data":33},"ok",{"site_id":25,"language":24,"slug":34,"title":13,"keywords":35,"description":14,"schema_data":36,"social_meta":87,"head_meta":89,"extra_data":91,"updated_unix":29},"modeling-asymmetry-in-the-rotation-of-disk-galaxies-doctor-of-philosophy-thesis","",{"@graph":37,"@context":86},[38,54,69],{"@type":39,"itemListElement":40},"BreadcrumbList",[41,45,48,51],{"item":42,"name":43,"@type":44,"position":21},"https://docshare.wps.com","Home","ListItem",{"item":46,"name":47,"@type":44,"position":20},"https://docshare.wps.com/document/","Document",{"item":49,"name":12,"@type":44,"position":50},"https://docshare.wps.com/document/research-report/",3,{"item":52,"name":13,"@type":44,"position":53},"https://docshare.wps.com/document/modeling-asymmetry-in-the-rotation-of-disk-galaxies-doctor-of-philosophy-thesis/135201/",4,{"url":52,"name":13,"@type":55,"author":56,"headline":13,"publisher":58,"fileFormat":61,"inLanguage":24,"description":14,"dateModified":62,"datePublished":63,"encodingFormat":61,"isAccessibleForFree":64,"interactionStatistic":65},"DigitalDocument",{"name":9,"@type":57},"Person",{"url":42,"name":59,"@type":60},"DocShare","Organization","application/pdf","2026-08-23","2026-08-21",true,{"@type":66,"interactionType":67,"userInteractionCount":20},"InteractionCounter",{"@type":68},"ViewAction",{"@type":70,"mainEntity":71},"FAQPage",[72,78,82],{"name":73,"@type":74,"acceptedAnswer":75},"What is the main research focus of the dissertation?","Question",{"text":76,"@type":77},"The dissertation focuses on modeling asymmetry in the rotation of disk galaxies and on how such asymmetries and observational effects influence kinematic inferences.","Answer",{"name":79,"@type":74,"acceptedAnswer":80},"How does the work address weak gravitational lensing in galaxy rotation modeling?",{"text":81,"@type":77},"It introduces a framework that combines imaging and kinematics to extract weak-lensing shear, accounting for distortions to coordinate systems and velocity-field contours.",{"name":83,"@type":74,"acceptedAnswer":84},"What datasets and analyses are used for barred galaxies?",{"text":85,"@type":77},"The dissertation uses SDSS-IV/MaNGA data to fit bisymmetric kinematic models, and it applies Nirvana-related analyses to characterize bar regions and associated stellar population gradients.","https://schema.org",{"og:url":52,"og:type":88,"og:title":13,"og:site_name":59,"og:description":14},"article",{"robots":90,"canonical":52},"index,follow",{"doc_id":7,"site_id":25},{"code":4,"msg":5,"data":93},[94,98,102,106,111,116,121,124,129,132,136],{"id":21,"doc_module":4,"doc_module_name":47,"category_name":95,"show_sort_weight":96,"slug":97},"Story & Novel",90,"story-novel",{"id":20,"doc_module":4,"doc_module_name":47,"category_name":99,"show_sort_weight":100,"slug":101},"Literature",80,"literature",{"id":53,"doc_module":4,"doc_module_name":47,"category_name":103,"show_sort_weight":104,"slug":105},"Exam",70,"exam",{"id":107,"doc_module":4,"doc_module_name":47,"category_name":108,"show_sort_weight":109,"slug":110},5,"Comic",60,"comic",{"id":112,"doc_module":4,"doc_module_name":47,"category_name":113,"show_sort_weight":114,"slug":115},6,"Technology",50,"technology",{"id":117,"doc_module":4,"doc_module_name":47,"category_name":118,"show_sort_weight":119,"slug":120},7,"Healthcare",40,"healthcare",{"id":11,"doc_module":4,"doc_module_name":47,"category_name":12,"show_sort_weight":122,"slug":123},30,"research-report",{"id":125,"doc_module":4,"doc_module_name":47,"category_name":126,"show_sort_weight":127,"slug":128},9,"Religion & Spirituality",20,"religion-spirituality",{"id":127,"doc_module":4,"doc_module_name":47,"category_name":130,"show_sort_weight":127,"slug":131},"World Cup","world-cup",{"id":133,"doc_module":4,"doc_module_name":47,"category_name":134,"show_sort_weight":133,"slug":135},10,"Lifestyle","lifestyle",{"id":137,"doc_module":4,"doc_module_name":47,"category_name":138,"show_sort_weight":107,"slug":139},19,"General","general"]