{"created":"2023-06-20T13:20:31.485350+00:00","id":550,"links":{},"metadata":{"_buckets":{"deposit":"049c102f-98cb-4628-8149-97eb8cb09875"},"_deposit":{"created_by":1,"id":"550","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"550"},"status":"published"},"_oai":{"id":"oai:ir.soken.ac.jp:00000550","sets":["2:427:13"]},"author_link":["0","0","0"],"item_1_creator_2":{"attribute_name":"著者名","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"今井, 弘二"}],"nameIdentifiers":[{}]}]},"item_1_creator_3":{"attribute_name":"フリガナ","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"イマイ, コウジ"}],"nameIdentifiers":[{}]}]},"item_1_date_granted_11":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2006-09-29"}]},"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_12":{"attribute_name":"要旨","attribute_value_mlt":[{"subitem_description":"I present J- and Ks-band galaxy counts and galaxy colors covering 750<br />arcminutes<sup>2</sup> in the deep AKARI North Ecliptic Pole (NEP) field, using the<br />FLeridA Multi-object lmaglng Near-ir Grism Observational Spectrometer<br />(FLAMINGOS) on the Kitt Peak National Observatory (KPNO) 2.1 m<br />telescope. The limiting magnitudes with a slgnal-to-noise ratio of three in<br />the deepest regions are 21.85 and 20.15 in the J- and Ks-bands respectively<br />in the Vega magnitude system.<br /><br />     The J-and Ks-band galaxy counts in the AKARINEP field are broadly in<br />good agreement with those of other results in the literature, however the<br />counts show a characteristic change in the galaxy count slope in both the J-and<br />Ks-bands. The slope of the J-band galaxy counts per square degree per<br />magnitude clearly changes at J ～ 19.5 from d(logN)/dm = 0.39 ± 0.02 to<br />0.30 ± 0.03, while　the ks-band galaxy counts shows a clear 'bump' in<br />the magnitude range 18.0 < Ks < 19.5. The B -Ks color distribution of the<br />galaxy samples also shows an obvious change around the `bump'<br />magnitude of the ks-band counts. The number of faint blue samples in the<br />magnitude range 18.5 <Ks < 19.5 is signincantly larger than that of ks<<br />17.5 samples.<br /><br />     In order to find a clue tounderstandthe ongln of the change in J- and<br />ks-band count slopes and the bluer trend at fainter magnitudes below the<br />bump of Ks-band counts, I also investigated the number counts of Ks-band<br />selected high redshift galaxy populations:the extremely red objects (EROs),<br />the B,z and K-band selected galaxies (BzKs) and the distant red galaxies<br />(DRGs). I foundthat the number counts of both the passive EROs and the<br />passive BzKs have shallower slopes at fainter magnitudes and turnovers at<br />Ks ～ 18.5 and Ks ～ 19.0, respectively, while the number count of the<br />star-fomlng BzKs is a single power-law with a steeper slope. The observed<br />number counts of these passive populations are compared with a backward<br />evolution model allowing the number density evolution. The pure<br />luminosity evolution model without density evolution fails to explain the<br />observed counts at faint magnitudes (Ks > 17.0), while the model with a<br />negative density evolution is consistent with the observed counts of the<br />passive populations.<br /><br />     Based on these results, I also investigated an evolutional scenario of<br />galaxy populations which can explainthe observed K-band count by using<br />three components (early-type, late-type and star-forming populations),<br />backward evolution model with type-dependent luminosity functions. I<br />found that not onlythe ellipticals but also the spiral galaxy population has<br />to follow the negative density evolution whilethe starburst population<br />shows the strong positive density evolution.<br /><br />     Finally,the on-going NEP deep surveys at 2-26 pm with AKARI will<br />provide us with new and critical pieces of information to verify and improve<br />the galaxy evolution scenario discussed in this thesis.","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986号","subitem_description_type":"Other"}]},"item_1_select_14":{"attribute_name":"所蔵","attribute_value_mlt":[{"subitem_select_item":"有"}]},"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":"11 宇宙科学専攻"}]},"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":"IMAI, Koji","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"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","filename":"甲986_要旨.pdf","filesize":[{"value":"361.4 kB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"要旨・審査要旨","url":"https://ir.soken.ac.jp/record/550/files/甲986_要旨.pdf"},"version_id":"892b91e7-74a8-410f-82ec-2ea81a568e4e"}]},"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":"A NEAR INFRARED SURVEY IN THE AKARI NORTH ECLIPTIC POLE FIELD","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"A NEAR INFRARED SURVEY IN THE AKARI NORTH ECLIPTIC POLE FIELD"},{"subitem_title":"A NEAR INFRARED SURVEY IN THE AKARI NORTH ECLIPTIC POLE FIELD","subitem_title_language":"en"}]},"item_type_id":"1","owner":"1","path":["13"],"pubdate":{"attribute_name":"公開日","attribute_value":"2010-02-22"},"publish_date":"2010-02-22","publish_status":"0","recid":"550","relation_version_is_last":true,"title":["A NEAR INFRARED SURVEY IN THE AKARI NORTH ECLIPTIC POLE FIELD"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-06-20T16:12:44.019178+00:00"}