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Information to Users INFORMATION TO USERS This manuscript has been reproduced from the microfrlm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type o f computer printer. The quality of this reproduction is dependent upon the quality of the copy subm itted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back o f the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. IBgher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell & Howell Information Company 300 North Zed) Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 NOTE TO USERS The original manuscript received by UMI contains pages with indistinct print. Pages were microfilmed as received. This reproduction is the best copy available UMI STAR FORMATION IN CAMELOPARDALIS; C am O B I by David Anthony Lyder B.Sc.. University of Alberta 1982 B.Sc.. University of Alberta I9ST M.Sc.. University of Alberta 1989 A Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY in the Department of Physics and Astronomy We accept this thesis as conforming to the required standard Dr. C. Gower. Supervisor (Department of Phvsics and .\stronomv) __________ Dr. C. R. Purton. Co-Supervisor (Dominion Radio .Astrophysical Observatory) Dr. C. D. Scarfe. Departmental Member (Department of Physics and .\stronomy) Dr. F /p . Hart wick. Departmental Member (Department of Physics and .Astronomy V Dr. G. Miller. Outside Member (Department of Mathematics and Statistics) Dr. J/M . MacLeod. External Examiner (.James Clerk Maxwell Telescope) © D.AVID A N T H O N Y LYDER. 1997 L niversity of Victoria .All rights reserved. Dissertation may not be reproduced in whole or in part, by photocopying or other means, without the permission of the author. u Supervisors: Drs. A. C. Gower and C. R. Purton ABSTRACT Star formation in the Cam OBI region is investigated. Star formation, in general, is considered in terms of three elements: a) the structural relationship between the parent molecular clouds and newly formed stars, b) the temporal evolution of the parent molecular clouds, and c) the probability of the occurrence of star formation. Star formation in Cam OBI. over the range in I an d 6 considered in this work, is concentrated in the vicinity of Cam Rl and appears to have led to the formation of three distinct stellar groups: a) Group I. formed ~ I — 50 x 10® yr ago. and located spatially and kinematically between two CO complexes, b) Group II. form ed ~ 1 — 3 x 10® yr ago. and coincident with one of the previously mentioned complexes, and c) Group III. the youngest group, formed ~ I — 20 x 10"* yr ago. and located at the current point of intersection between the two complexes in (a). The mass function (MF) for Groups I and II is similar to the cloud mass function of the parent molecular clouds, i.e.. a power-law with exponent q ~ 2. .A. similar analysis for the Group III stars and associated molecular clouds cannot be performed due to the relatively small numbers in both samples. The star forming efficiency (SEE) in all cases is ~ 1%. It is proposed that cloud-cloud collisions between the CO complexes in the region triggered the formation of Groups I and III. while Group II was produced by a shock induced by the radiation pressure and stellar winds from the stars in Group I. .An analysis of the molecular cloud structure in Cam OBI and the background Perseus arm also shows that the clouds in both regions are turbulent, and typical of clouds seen elsewhere in the Galaxy. However, the clouds in Cam OBI show a large dispersion in the degree with which they are self-gravitating, with the Ill larger, warmer clouds being grav'itationally bound. The principal data set for this work comprises fully sampled (J=l-0) ob­ servations of the western half of Cam OBI. which were obtained at the Center for .Astrophysics during the winter of 1992-1993. These data have an effective resolu­ tion of 10'. a velocity resolution of 0.6-5 km s~‘. and a sensitivity of 0.11-5 K. High resolution (20") observations of the *^C0 (J=2-l) transition of the most active star forming region were obtained with the James Clerk Maxwell Telescope during the w in ter of 1994-199-5. These observations led to th e discovery of a second outflow. .AFGL 490 — iki. associated with IR.AS 032344-5843. in the immediate vicinity of the very well-studied molecular outflow .AFGL 490. .Additional observations of the CH 3OH maser (5i — Oo-A'*’). taken with the 26m telescope at the Dominion Radio •Astrophysical Observatory during the fall of 1994. did not reveal any such maser- ing activity in the Cam OBI region, but did lead to the discovery of a new maser. associated w ith IR.AS 024-5-54-6034. in th e background Perseus arm . IV ABSTRACT cont. Dr. C. Gower. Supervisor (Department of Physics and .\stronomy) Dr. C. R. Purton. Co-Supervisor (Dominion Radio .Astrophysical Observatory) Dr. C. D. Scarfe. Departmental Member (Department of Physics and .Astronomy) Dr. ^ D . Hartwick. Departmental Member (Department of Physics and .Astronomy) Dr. G. Miller. Outside Member (Department of Mathematics and Statistics) D) rr./j. ./j. M. MacLeod.M acLeod. External1 Examiner (.James Clerk Maxwell Telescope) Table of Contents Title Page ...............................................................................................................................................i A bstract .................................................................................................................................................ii Table of Contents .............................................................................................................................. v List of Tables .......................................................................................................................................x List of Figures .................................................................................................................................. xii Acknowledgements ........................................................................................................................ xvi Dedication .........................................................................................................................................xix VI C h ap ter ............................................................................................................................................ Page Introduction ...........................................................................................................................................1 Chapter I General Overview of CO Observing .......................................................... 15 1.1 Introduction ..............................................................................................15 1.2 Physical Principles .................................................................................16 1.3 Physical Quantities of Interest ........................................................ 25 1.3.1 Measured Physical Quantities .......................................................26 1.3.2 Derived Physical Quantities ...........................................................29 1.4 Summary of .Assumptions and Constraints ............................... 32 Chapter 2 The Present Survey ......................................................................................... 33 2.1 Introduction ............................................................................................. 33 2 .2 T he Cf.A Telescope ...............................................................................34 2.3 The Observations .................................................................................. 39 2.3.1 Observing Procedure .........................................................................40 2.4 The Data ...................................................................................................43 2.4.1 b L's. V ...................................................................................................... 46 2.4.2 / vs. V ...................................................................................................... 48 2.4.3 I vs. b: Local Emission ( + 10 to — 5 km s“^ )..........................50 2.4.4 I vs. b: Cam OBI Emission (—5 to — 22 km s“^)................53 2.4.5 / C6 . b: Interarm Emission (—22 to —30 km s"M................ 57 2.4.6 I vs. b: Perseus Emission (—30 to — 70 km s“^)...................59 2.4.7 I vs. b: O uter G alaxy ( — 70 to — 130 km s " ^ )....................... 62 2.5 Conclusions ............................................................................................
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