Browsing by Author "Wu, Hong"

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    ALMA Observation of NGC 5135: The Circumnuclear CO (6-5) and Dust Continuum Emission at 45 pc Resolution
    (2018) Cao, Tianwen; Lu, Nanyao; Xu, C. Kevin; Zhao, Yinghe; Madhav Kalari, Venu; Gao, Yu; Charmandaris, Vassilis; Diaz Santos, Tanio; Van der Werf, Paul; Cao, Chen; Wu, Hong; Inami, Hanae; Evans, Aaron S.
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    Ionized and Cold Gas Components in Low Surface Brightness Galaxy AGC 102004
    (2024) Cao, Tian-Wen; Li, Zi-Jian; Chen, Pei-Bin; Zhang, Chun-Yi; Galaz, Gaspar; Cheng, Cheng; Yu, Qingzheng; Kalari, Venu M.; Wang, Junfeng; Wu, Hong
    We present the integral field spectroscopic observations of ionized gas (H alpha and [N II]) using the PCWI, along with deep CO(2-1) observations by the '(U) over bar'(u) over bar receiver on JCMT for AGC 102004. The velocity field of H alpha shows an anomalous distribution in the northwestern (NW) disk. The H alpha spectrum is well-fitted by two Gaussian components, and the weak Gaussian component is dominated by the anomalous H alpha in the NW disk. The Gaussian fit center of H alpha emission is offset by +24.2 km s(-1) from the systemic velocity obtained from the H i emission. We derive the gas-phase metallicity, 12+log(O/H), using [N II]lambda 6583/H alpha ratio as a proxy. The mean value of 12+log(O/H) is 8.30 +/- 0.19 over the whole galaxy. The metallicity in the outer disk is lower than the detection limit of 7.72, indicating the metallicity gradient exists in AGC 102004. We speculate a minor/mini-merger event could have happened to the NW disk. CO(2-1) emission has nondetection in AGC 102004, reaching a noise level of 0.33 mK smoothed to 30 km s(-1). The upper limit of molecular gas mass in AGC 102004 is 2.1 x 107 M-circle dot with X-CO = 3.02 x 1020 cm(-2) (K km s(-1))(-1). The MH2 /M-HI(corr) of AGC 102004 is lower than 0.0037 and lower than that of normal galaxies.
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    Nature-Based Solutions as Critical Urban Infrastructure for Water Resilience
    (Edward Elgar Publishing, 2023) McPhillips, Lauren; Wu, Hong; Rojas Quezada, Carolina Alejandra; Rosenzweig, Bernice; Sauer, Jason R.; Winfrey, Brandon
    Nature-based solutions (NBS) are key for managing water resources, as well as providing many other benefits. While traditionally “gray” highly engineered strategies have been used to manage water in urban areas, we articulate the role that NBS can play in managing water related to flooding, drought, and water quality challenges. Specifically, NBS for water can range from hybrid ecological-technological features explicitly engineered to manage stormwater to other designed or intact natural features such as wetlands or parks that may provide water management as a co-benefit. Criteria are reviewed for choosing the best NBS for the intended goal(s), and we showcase several case examples of NBS for water resilience from around the world. Remaining knowledge gaps for NBS for water implementation include space challenges, changes in performance over time, and incorporation of NBS that are not explicitly engineered for water management into existing management and regulatory frameworks.