用WISE和SDSS表征中红外河外天区
Characterizing the Mid-IR Extragalactic Sky with WISE and SDSS
摘要：
宽视场红外巡天探测器（WISE）已经完成了3.4-22微米的全天巡天。我们合并的WISE数据与光学SDSS数据，并提供了一个唯象表征的中红外，河外源。WISE在3.4 μ m（W1）处最灵敏，在22 μ m（W 4）处最不灵敏。W1波段探测到z \gtrsim 1的大质量早型星系。这比SDSS发现的早型星系更遥远，这与28%的3.4微米源有微弱或没有r波段对应物（r>22.2）的事实相一致。相比之下，92-95%的12和22微米光源具有r<22.2的SDSS光学对应物。WISE 3.4微米探测器在SNR（W1）>7时能探测到整个SDSS类星体目录的89.8%，但在SNR（W 4）>5时，22微米探测器只能探测到18.9%。我们表明，WISE颜色单独是有效的隔离恒星（或本地早型星系），恒星形成星系和强活动星系核/类星体在z<3。我们强调了WISE颜色的三个主要应用：（1）选择z 0.8和W2<15.2的强AGN/类星体<3 using W1-W2>标准，产生人口普查。这些强活动星系核/类星体候选者的面密度为67.5+-0.14/deg^2。(2)尘埃遮蔽的2型活动星系核/类星体候选者的选择。我们发现WISE W1-W2>0.8，W2 <15.2 combined with r-W2>6（Vega）色可以用来识别第二类活动星系核候选者。这些2型活动星系核候选者的比例是所有WISE颜色选择活动星系核的1/3。(3)选择z \sim 2处具有极红色、r-W 4>14或在3.4和4.6微米波段中检测不到的良好检测的22微米源的ULIRG。在信噪比（W 4）>5（通量（W 4）≥ 2.5mJy）时，z~2 r-W 4>14的ULIRGs的面密度为0.9 ± 0.07/deg^2，这与小面积Spitzer观测结果一致。少数这些高红移ULIRGs的光谱证实了我们的选择，并揭示了一个可能的趋势，光学暗淡或r-W 4红候选人在较高的红移。
英文摘要：
The Wide-field Infrared Survey Explorer (WISE) has completed its all-sky survey at 3.4-22 micron. We merge the WISE data with optical SDSS data and provide a phenomenological characterization of mid-IR, extragalactic sources. WISE is most sensitive at 3.4micron(W1) and least at 22micron(W4). The W1 band probes massive early-type galaxies out to z\gtrsim1. This is more distant than SDSS identified early-type galaxies, consistent with the fact that 28% of 3.4micron sources have faint or no r-band counterparts (r>22.2). In contrast, 92-95% of 12 and 22micron sources have SDSS optical counterparts with r<22.2. WISE 3.4micron detects 89.8% of the entire SDSS QSO catalog at SNR(W1)>7, but only 18.9% at 22micron with SNR(W4)>5. We show that WISE colors alone are effective in isolating stars (or local early-type galaxies), star-forming galaxies and strong AGN/QSOs at z<3. We highlight three major applications of WISE colors: (1) Selection of strong AGN/QSOs at z<3 using W1-W2>0.8 and W2<15.2 criteria, producing a census of this population. The surface density of these strong AGN/QSO candidates is 67.5+-0.14/deg^2. (2) Selection of dust-obscured, type-2 AGN/QSO candidates. We show that WISE W1-W2>0.8, W2<15.2 combined with r-W2>6 (Vega) colors can be used to identify type-2 AGN candidates. The fraction of these type-2 AGN candidates is 1/3rd of all WISE color-selected AGNs. (3) Selection of ULIRGs at z\sim2 with extremely red colors, r-W4>14 or well-detected 22micron sources lacking detections in the 3.4 and 4.6micron bands. The surface density of z~2 r-W4>14 ULIRGs is 0.9+-0.07/deg^2 at SNR(W4)>5 (flux(W4)>=2.5mJy), which is consistent with that inferred from smaller area Spitzer surveys. Optical spectroscopy of a small number of these high-redshift ULIRGs confirms our selection, and reveals a possible trend that optically fainter or r-W4 redder candidates are at higher redshifts.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
