我們在 COSMOS-CANDELS 區域進行了 SCUBA-2 450 微米的觀測，這是 JCMT 大型計劃 SCUBA-2 超深成像 EAO 巡天（SCUBA-2 Ultra Deep Imaging EAO Survey，STUDIES）的一部分。我們的 450 微米和 850 微米的觀測影像覆蓋了 450 平方角分的面積。在每張影像的最深區域，我們達到了儀器雜訊級分別為 σ_450 = 0.59 mJy beam^-1 和 σ_850 = 0.09 mJy beam^-1。對應的致淆雜訊級在 450 微米和 850 微米分別估計為 0.65 和 0.36 mJy beam^-1，而經驗法則下的致淆極限則為 3.4 和 2.0 mJy。在 4（3.5）σ 閾值之上，我們在 450 微米波段檢測到 360（479）個源，在 850 微米波段檢測到 237（314）個源。我們推導了 450 微米波段最深的空場數量統計，覆蓋了 2 到 43 mJy 的通量密度範圍。這些結果與其他 SCUBA-2 空場和重力透鏡星系團的觀測一致，但低於各種模型預測的數量。我們將這些數據與其他區域進行比較，發現在 6 角分尺度上，450 微米波段的區域間差異與帕松雜訊一致，因此在此尺度上沒有明顯的二維聚集現象的證據。此外，我們推導出 450 微米波段下至 2.1 mJy 的累積表面亮度為 57.3^{+1.0}_{-6.2} Jy deg^-2，以由 COBE 和 Planck 測量的數據為基準，這相當於貢獻了 450 微米星系背景光（EBL）的 (41±4)%。我們的結果表明，450 微米波段的 EBL 可能在 0.08^{+0.09}_{-0.08} mJy 完全解析，這有望通過極深的重力透鏡星系團觀測和新一代大口徑次毫米望遠鏡實現。此外，我們利用高解析度的干涉儀源目錄，識別了 450 微米源的對應體。為了在 COSMOS 場內擴展有限的 450 微米樣本，我們開發了一種基於光學到近紅外光度測量的機器學習方法。這種方法的精確度達到了 0.97±0.02，召回率達到 0.99±0.01。我們還展示了 JWST NIRCam 4.4 微米影像的處理過程，這對於近紅外對應體的識別有很大幫助。;We present confusion-limited SCUBA-2 450-μm observations in the COSMOS-CANDELS region as part of the JCMT Large Program, SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES). Our maps at 450 μm and 850 μm cover an area of 450 arcmin^2. We achieved instrumental noise levels of σ_450 = 0.59 mJy beam^-1 and σ_850 = 0.09 mJy beam^-1 in the deepest area of each map. The corresponding confusion noise levels are estimated to be 0.65 and 0.36 mJy beam^-1, and the confusion limits at the rule-of-thumb source density is 3.4 and 2.0 mJy at 450 and 850 μm, respectively. Above the 4 (3.5) σ threshold, we detected 360 (479) sources at 450 μm and 237 (314) sources at 850 μm. We derive the deepest blank-field number counts at 450 μm, covering the flux-density range of 2 to 43 mJy. These are in agreement with other SCUBA-2 blank-field and lensing-cluster observations, but are lower than various model counts. We compare the counts with those in other fields and find that the field-to-field variance observed at 450 μm at the R=6 arcmin scale is consistent with Poisson noise, so there is no evidence of strong 2-D clustering at this scale. Additionally, we derive the integrated surface brightness at 450 μm down to 2.1 mJy to be 57.3^{+1.0}_{-6.2} Jy deg^-2, contributing to (41±4)% of the 450-μm extragalactic background light (EBL) measured by COBE and Planck. Our results suggest that the 450-μm EBL may be fully resolved at 0.08^{+0.09}_{-0.08} mJy, which extremely deep lensing-cluster observations and next-generation submillimeter instruments with large aperture sizes may be able to achieve. In addition, we identified counterparts for our 450-μm sources using high-resolution interferometric source catalogs. To extend limited 450-μm sample across the COSMOS field, we developed a tentative machine learning method based on optical to near-infrared (NIR) photometry. This method achieved a precision of 0.97±0.02 and a recall of 0.99±0.01. We also present the data reduction process for the JWST NIRCam 4.4-μm mosaic image, aiding NIR counterpart identification.
