{"_buckets": {"deposit": "4e129324-6e82-439d-826c-433ca1f72362"}, "_deposit": {"created_by": 1, "id": "428", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "428"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00000428", "sets": ["11"]}, "author_link": ["0", "0", "0"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2007-03-23", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "池田, 紀夫"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "イケダ, ノリオ"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2007-03-23"}]}, "item_1_degree_grantor_5": {"attribute_name": "学位授与機関", "attribute_value_mlt": [{"subitem_degreegrantor": [{"subitem_degreegrantor_name": "総合研究大学院大学"}]}]}, "item_1_degree_name_6": {"attribute_name": "学位名", "attribute_value_mlt": [{"subitem_degreename": "博士（理学）"}]}, "item_1_description_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "2007017", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "We have carried out H\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003e(\u003ci\u003eJ\u003c/i\u003e=1-0) core unbiased surveys in the nearby\u003cbr /\u003e massive star－and cluster－forming giant molecular clouds Orion A，Orion B，\u003cbr /\u003eand Cepheus OB3.　Our observations were carried out using the Nobeyama\u003cbr /\u003e45 m radio telescope with the 25-BEam Array Receiver System (BEARS).\u003cbr /\u003eOur surveys are very unique in that large areas (1.4 － 1.5 square degrees)\u003cbr /\u003e of the clouds were covered with very high spatial resolution of 20 － 27\" \u003cbr /\u003e enough to resolve dense  cores, and with deep integration （1\u0026sigma;～0.1 K in \u003ci\u003eT\u003c/i\u003e*\u003csmall\u003eA\u003c/small\u003e），\u003cbr /\u003e resulting in the sensitive mass detection of 1.6 － 3.5 \u003ci\u003eM\u003c/i\u003e\u003csmall\u003e\u0026Theta;\u003c/small\u003e for dense cores in\u003cbr /\u003ethe clouds . These observational advantages allow us to derive reliable core\u003cbr /\u003emass functions（CMFs）with a good statistics of sample number～30 － 240\u003cbr /\u003eand a wide － mass range of 2 \u0026le; \u003ci\u003eM / M\u003c/i\u003e\u0026Theta; \u0026le;100．\u003cbr /\u003e　The morphology of the H\u003csup\u003e13\u003c/sup\u003e CO \u003csup\u003e＋\u003c/sup\u003e（\u003ci\u003eJ\u003c/i\u003e＝1 - 0）emission in the Orion A and\u003cbr /\u003eB is very similar to that of the dust continuum emission. In addition，our\u003cbr /\u003eobservations of the Cepheus cloud is the first unbiased one of the dense gas\u003cbr /\u003ewith such a high spatial resolution．We identified 236，98，and 31 dense cores\u003cbr /\u003efrom our data with the clumpfind algorithm in the Orion A，B，and Cepheus \u003cbr /\u003eOB3, respectively. All the cores seem to be almost in virial equilibrium\u003cbr /\u003eindependently of whether the cores are thermal or turbulent. Furthermore,\u003cbr /\u003ethe majority of the cores in the three clouds has very similar distributions\u003cbr /\u003eof the physical parameters. This suggests that the most of the cores are the\u003cbr /\u003ecommon ones, while there are a few peculiar cores whose velocity widths and\u003cbr /\u003eradii are larger than 1 km s\u003csup\u003e-1\u003c/sup\u003e and 0.14 pc, respectively. We derived the\u003cbr /\u003eH\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003eCMFs of the clouds and found that these are consistent with those\u003cbr /\u003eby previous studies in the sense of their power-law indices in the high-mass\u003cbr /\u003epart of－2.1-－2.4 and the existence of turnovers near 5 － 10\u003ci\u003eM\u003c/i\u003e\u003csmall\u003e\u0026Theta;\u003c/small\u003e.\u003cbr /\u003e　We showed that the dust GMF can be produced from the H\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003e CMF\u003cbr /\u003eassuming that the dust cores correspond to the inner denser（＞10\u003csup\u003e6\u003c/sup\u003e cm\u003csup\u003e－3\u003c/sup\u003e）\u003cbr /\u003estructures of the H\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003e ones and the core density profi1e which is propor-\u003cbr /\u003etional to R\u003csup\u003e－2\u003c/sup\u003e　Furthermore we predicted IMFs from the H\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003e CMFs in \u003cbr /\u003ethe three clouds assuming that all the cores form stars simultaneously and the\u003cbr /\u003estar formation efficiency is uniform over the cores. We also considered binary\u003cbr /\u003eformations assuming that the core multiplicity is uniform over the cores. We \u003cbr /\u003e found that the high－mass part power-law slope of the predicted IMFs agree\u003cbr /\u003ewell with that of the Orion Nebula Cluster IMF and of the Galactic-field\u003cbr /\u003eaveraged IMF for a star formation efficiency of ～25 - 50％．These findings\u003cbr \u003e suggest that the IMF is determined at the time of the H\u003csup\u003e13\u003c/sup\u003eCO\u003csup\u003e＋\u003c/sup\u003e core（the\u003cbr /\u003edensity of～10\u003csup\u003e4-5 \u003c/sup\u003ecm-3 or less）formation，rather than tht of the dust cores\u003cbr /\u003e of＞10\u003csup\u003e6\u003c/sup\u003ecm\u003csup\u003eF-3\u003c/sup\u003e．\u003cbr /\u003e　On the other hand，the predicted IMF seem to have less number of stars\u003cbr /\u003econsiderably in the low-mass part below \u003ci\u003e2M\u003c/i\u003e\u003csmall\u003e\u0026Theta;\u003c/small\u003e，resulted from the turnover of\u003cbr /\u003ethe CMFs. As one of the possible causes of the CMF turnover，we modeled\u003cbr /\u003econfusion along the line of sight，mainly due to the shadowing of low－mass\u003cbr /\u003ecores caused by massive cores．The shadowing-corrected predicted IMFs\u003cbr /\u003eagree well with the IMFs. We found that the shadowing－corrected CMFs do\u003cbr /\u003enot have turnovers, suggesting that the apparent turnovers in the observed\u003cbr /\u003e CMFs may not correspond to those of the IMFs. On the other hand，their\u003cbr /\u003epowe-law indices of the shadowing － corrected CMFs are very similar to each\u003cbr /\u003eother although the three clouds have apparent difference in star－forming ac-\u003cbr /\u003etivities.　This　implies　a　common　core　formation processes that is insensitive\u003cbr /\u003eto environmental parameters，leading to the origin of the universality of the\u003cbr /\u003eIMF. \u003cbr /\u003e　We discovered four cores with large velocity widths，significantly wider\u003cbr /\u003ethan those of the other cores，only toward the M42 H \u003csmall\u003eII\u003c/small\u003e region and the Cep-A\u003cbr /\u003ecompact H\u003csmall\u003eII\u003c/small\u003e region.　The finding of the large-velocity width cores suggests\u003cbr /\u003ethat the energy input from the H\u003csmall\u003eII\u003c/small\u003e regions increases the velocity width. Since\u003cbr /\u003ethe large-velocity width cores can produce the most massive stars owing to\u003cbr /\u003etheir large mass accretion rates，the massive star formamations in the Orion\u003cbr /\u003eA and Cepheus OB3 clouds are likely to be caused by the environmental\u003cbr /\u003estellar activities．This may imply that the IMF have additional turnover\u003cbr /\u003eat the high-mass end，although the statistical uncertainties of the observed\u003cbr /\u003eIMF are too large to recognize the turnover. In the Orion B, on the other\u003cbr /\u003ehand，there is no core with large velocity width significantly One of the\u003cbr /\u003eexplanations is that stellar activities in the Orion B cloud，in which the most\u003cbr /\u003eearliest star is O8，are less energetic than those of O6 and O7 in the Orion\u003cbr /\u003eA and Cepheus，respectively  This may indicate that stellar energy sources\u003cbr /\u003eearlier than O7－O6 are required to influence the moat massive stars of the\u003cbr /\u003enext generation.\u003cbr /\u003e　We conclude that the IMF originates from the CMF. It implies that in-\u003cbr /\u003evestigating the CMF formation processes is equivalent to revealing the origin\u003cbr /\u003eof the IMF. We tested the proposed core formation prosesses such as grav-\u003cbr /\u003eitational fragmentation，collision and coalescence，accretion，and turbulent\u003cbr /\u003efragmentation based on our core catalog.　We conclude that the turbulent\u003cbr /\u003efragmentation is the most plausible one of them.", "subitem_description_type": "Other"}]}, "item_1_description_7": {"attribute_name": "学位記番号", "attribute_value_mlt": [{"subitem_description": "総研大甲第1032号", "subitem_description_type": "Other"}]}, "item_1_select_14": {"attribute_name": "所蔵", "attribute_value_mlt": [{"subitem_select_item": "有"}]}, "item_1_select_16": {"attribute_name": "複写", "attribute_value_mlt": [{"subitem_select_item": "application/pdf"}]}, "item_1_select_8": {"attribute_name": "研究科", "attribute_value_mlt": [{"subitem_select_item": "物理科学研究科"}]}, "item_1_select_9": {"attribute_name": "専攻", "attribute_value_mlt": [{"subitem_select_item": "09 天文科学専攻"}]}, "item_1_text_10": {"attribute_name": "学位授与年度", "attribute_value_mlt": [{"subitem_text_value": "2006"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "IKEDA, Norio", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_files": {"attribute_name": "ファイル情報", "attribute_type": "file", "attribute_value_mlt": [{"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 0, "filename": "甲1032_要旨.pdf", "filesize": [{"value": "330.3 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 330300.0, "url": {"label": "要旨・審査要旨", "url": "https://ir.soken.ac.jp/record/428/files/甲1032_要旨.pdf"}, "version_id": "cb80f4aa-9371-4fc7-88b2-00c8e39d8af0"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲1032_本文.pdf", "filesize": [{"value": "31.5 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 31500000.0, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/428/files/甲1032_本文.pdf"}, "version_id": "1fe28806-9714-4187-9c42-520210fdf669"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "eng"}]}, "item_resource_type": {"attribute_name": "資源タイプ", "attribute_value_mlt": [{"resourcetype": "thesis", "resourceuri": "http://purl.org/coar/resource_type/c_46ec"}]}, "item_title": "Dense Core Survey Toward Nearby Massive Star and Cluster Forming Giant Molecular Clouds: Origin of the Initial Mass Function", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Dense Core Survey Toward Nearby Massive Star and Cluster Forming Giant Molecular Clouds: Origin of the Initial Mass Function"}, {"subitem_title": "Dense Core Survey Toward Nearby Massive Star and Cluster Forming Giant Molecular Clouds: Origin of the Initial Mass Function", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "1", "path": ["11"], "permalink_uri": "https://ir.soken.ac.jp/records/428", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "428", "relation": {}, "relation_version_is_last": true, "title": ["Dense Core Survey Toward Nearby Massive Star and Cluster Forming Giant Molecular Clouds: Origin of the Initial Mass Function"], "weko_shared_id": 1}